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851.
Morphology of the copulatory organ in Ortalis canicollis (Aves: Cracidae) and early evolution of the phallus in birds
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Diego Matiussi Previatto Gustavo Leite Gonçalves Marcela Carvalho Ortiz Carla Danielle de Melo‐Soares Sérgio Roberto Posso 《Acta zoologica》2018,99(1):42-51
We studied the morphology of the copulatory organ of Ortalis canicollis and its evolution in birds. The phallus of O. canicollis is intromittent, with a blind tubular cavity and two distinct regions when erect: the base of the phallus, which shows the mucosa smooth and lined by a pseudostratified columnar epithelium, and the tubular portion, which shows the mucosa lined by a keratinized stratified squamous epithelium with little knobs. The phallus includes two vascular bodies at the cranial portion in the urodeum. A fibrocartilaginous body anchors the tubular portion therefrom up to the eversible portion. A branched elastic ligament inserts on different regions of the tubular portion. The phallus is plesiomorphic in birds and it has disappeared in Megapodius, Leipoa and Neoaves. The asymmetric phallus evolved early and it was retained in the basal branches of birds. The intromittent phallus is plesiomorphic in birds (found in Archosauria's ancestor), but Crypturellus, Numididae, Odontophoridae and Phasianidae have developed a non‐intromittent phallus a posteriori. The blind tubular cavity and the fibrocartilaginous body evolved as an adaptive convergence many times in birds. Therefore, this study shed some light on morphological aspects of the phallus and contributed to understand its evolution in birds. 相似文献
852.
Effects of pH and Salt Concentration on Stability of a Protein G Variant Using Coarse-Grained Models
853.
Effects of litter size and quality on processing by decomposers in a tropical savannah stream
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Renan de Souza Rezende Gustavo Figueiredo Marques Leite Kamilla Ramos Isabella Torres Alan M. Tonin José Francisco Gonçalves Júnior 《Biotropica》2018,50(4):578-585
Litter fragment size and quality can have profound effects on ecosystem functioning and global biogeochemical cycling due to differential utilization by decomposers. Here we study the influence of these factors on decomposers from two guilds found in a tropical savannah stream: invertebrate shredders of the genus Phylloicus and microorganisms. Containers (16 × 16 × 12 cm, ~ 3L) with either Phylloicus (cases removed; N = 16) or stream water containing microorganisms (N = 16) were supplied with litter from the species Inga laurina, Maprounea guianensis, and Richeria grandis, and cut into disks of 18.7, 13.2, and 8.1 mm in diameter (3 sizes × 3 species = 9 disks per container). Relative decomposition was greater for smaller leaf disks and disks of higher quality in microbial‐only cultures. Phylloicus preferentially harvested large fragments for case building, also preferring the leaves of M. guianensis and R. grandis, likely due increased robustness for case formation. Microbial decomposition resulted in ~20% litter mass loss compared to 30% in Phylloicus (of which 8% was used for case building and 24% for food). Thus, changes to input litter size, such as a decrease in leaf size after drought, may alter microbial decomposition and potentially affect shredder populations by limiting the availability of casing material. 相似文献
854.
Jorge E. Hernández-González Emir Salas-Sarduy Luisa F. Hernández Ramírez María J. Pascual Diego E. Álvarez Adriana Pabón Vitor B.P. Leite Pedro G. Pascutti Pedro A. Valiente 《Biochimica et Biophysica Acta (BBA)/General Subjects》2018,1862(12):2911-2923
Background
Falcipain 2 (FP-2) is the hemoglobin-degrading cysteine protease of Plasmodium falciparum most extensively targeted to develop novel antimalarials. However, no commercial antimalarial drugs based on FP-2 inhibition are available yet due to the low selectivity of most FP-2 inhibitors against the human cysteine proteases.Methods
A structure-based virtual screening (SVBS) using Maybridge HitFinder? compound database was conducted to identify potential FP-2 inhibitors. In vitro enzymatic and cell-growth inhibition assays were performed for the top-scoring compounds. Docking, molecular dynamics (MD) simulations and free energy calculations were employed to study the interaction of the best hits with FP-2 and other related enzymes.Results and conclusions
Two hits based on 4-(9H-fluoren-9-yl) piperazin-1-yl) methanone scaffold, HTS07940 and HTS08262, were identified as inhibitors of FP-2 (half-maximal inhibitory concentration (IC50)?=?64?μM and 14.7?μM, respectively) without a detectable inhibition against the human off-target cathepsin K (hCatK). HTS07940 and HTS08262 inhibited the growth of the multidrug-resistant P. falciparum strain FCR3 in culture (half-maximal inhibitory concentrations (IC50)?=?2.91?μM and 34?μM, respectively) and exhibited only moderate cytotoxicity against HeLa cells (Half-maximal cytotoxic concentration (CC50)?=?133?μM and 350?μM, respectively). Free energy calculations reproduced the experimental affinities of the hits for FP-2 and explained the selectivity with respect to hCatK.General significance
To the best of our knowledge, HTS07940 stands among the most selective FP-2 inhibitors identified by SBVS reported so far, displaying moderate antiplasmodial activity and low cytotoxicity against human cells. Hence, this compound constitutes a promising lead for the design of more potent and selective FP-2 inhibitors. 相似文献855.
Adriano Carneiro da Costa Fernando Santa-Cruz Brena F. Sena Ademar Lopes Nicole Leite Alexandre Rolim da Paz Álvaro A. B. Ferraz José-Luiz Figueiredo 《World journal of surgical oncology》2018,16(1):221
Background
Liposarcoma of the gallbladder is an extremely rare sarcoma, with only five cases reported in the literature according to our knowledge.Case presentation
A 71-year-old woman was referred to the Surgical Oncology Division of Napoleão Laureano Hospital (João Pessoa, PB, Brazil) due to a solid mass at the right side of the abdomen and fever, with no signs of jaundice. Abdominal ultrasonography and computed tomography (CT) evidenced an extensive gallbladder lobular formation adhered to the inferior border of the right hepatic lobe and cholelithiasis. The CT report suggested gallbladder liposarcoma. A cholecystectomy associated with resection of segments IV-B and V of the liver were performed. Intraoperative frozen sections were compatible with gallbladder sarcoma. Anatomopathological examination and immunohistochemistry confirmed dedifferentiated liposarcoma with foci of heterologous leiomyosarcomatous differentiation and undifferentiated fusocellular areas of high histological grade.Conclusion
This is the first case of dedifferentiated liposarcoma of the gallbladder to be reported.856.
Isis Leite Medeiros Mascarenhas Andrade Marcelo Schramm Mielke Nivaldo Peroni Alexandre Schiavetti 《Journal of ethnobiology and ethnomedicine》2018,14(1):80
Background
Traditional raft (jangada), piúba wood raft (jangada de pau de piúba), six-log raft (jangada de seis paus), and wooden raft (jangada de pau) are some of the names given to the traditional Brazilian watercrafts created from the buoyancy of bound logs. The traditional raft is a watercraft used and built by artisan fishermen who have, throughout generations, kept and improved knowledge related to this practice and the use of the plant species they need as raw materials. Active groups of these fishermen and their watercrafts are distributed along 200?km of the coast of the state of Bahia. The fishermen interviewed in this study are at the southern limit of distribution for the use of this type of vessel.Methods
This study aimed to characterize the use of the arboreal species applied in the construction of the traditional raft in the municipalities of Uruçuca, Ilhéus, and Canavieiras in the southern State of Bahia, Brazil. For this purpose, structured and semi-structured interviews were individually conducted with 36 fishermen, and walking tours were conducted with specialists in the construction of the watercraft.Results
We observed that the raftsmen use 21 species to construct the traditional raft. The features of the wood, such as density, flexibility, and availability, are the main criteria applied to choose the arboreal species. Some species are preferred, such as pau de jangada (Apeiba tibourbou) and biriba (Eschweilera ovata), which are the most frequently employed in watercraft manufacturing.Conclusions
The southern Bahia population is familiar with the different tree species that are linked to their fishing activities. The main link between the fishermen and the useful species is present in the practice of raft construction. Currently, the restricted access to raw materials limits this practice, which consequently results in the cultural erosion of this community.857.
Specific plasmid patterns and high rates of bacterial co‐occurrence within the coral holobiont
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Deborah C. A. Leite Joana F. Salles Emiliano N. Calderon Jan D. van Elsas Raquel S. Peixoto 《Ecology and evolution》2018,8(3):1818-1832
Despite the importance of coral microbiomes for holobiont persistence, the interactions among these are not well understood. In particular, knowledge of the co‐occurrence and taxonomic importance of specific members of the microbial core, as well as patterns of specific mobile genetic elements (MGEs), is lacking. We used seawater and mucus samples collected from Mussismilia hispida colonies on two reefs located in Bahia, Brazil, to disentangle their associated bacterial communities, intertaxa correlations, and plasmid patterns. Proxies for two broad‐host‐range (BHR) plasmid groups, IncP‐1β and PromA, were screened. Both groups were significantly (up to 252 and 100%, respectively) more abundant in coral mucus than in seawater. Notably, the PromA plasmid group was detected only in coral mucus samples. The core bacteriome of M. hispida mucus was composed primarily of members of the Proteobacteria, followed by those of Firmicutes. Significant host specificity and co‐occurrences among different groups of the dominant phyla (e.g., Bacillaceae and Pseudoalteromonadaceae and the genera Pseudomonas, Bacillus, and Vibrio) were detected. These relationships were observed for both the most abundant phyla and the bacteriome core, in which most of the operational taxonomic units showed intertaxa correlations. The observed evidence of host‐specific bacteriome and co‐occurrence (and potential symbioses or niche space co‐dominance) among the most dominant members indicates a taxonomic selection of members of the stable bacterial community. In parallel, host‐specific plasmid patterns could also be, independently, related to the assembly of members of the coral microbiome. 相似文献
858.
859.
José L. Cechella Marlon R. Leite Simone Pinton Gilson Zeni Cristina W. Nogueira 《Molecular neurobiology》2018,55(5):3832-3840
The progressive decline of neurological functions, such as learning and memory, is an unavoidable consequence of aging. Our previous work suggested that the combination of physical exercise and a diet supplemented with diphenyl diselenide improves age-related memory decline in rats. The present study investigated the effects of physical exercise and a diet supplemented with diphenyl diselenide on the levels of proteins involved in the hippocampal neuroprotection to figure out the mechanisms related to the beneficial effects of this intervention in aged rats. Male Wistar rats (27 months old) were fed daily with standard chow supplemented with 1 ppm of diphenyl diselenide and subjected to swimming training with a workload (1% of body weight, 20 min/day) for 4 weeks. The hippocampus was dissected from the brain and used for the western blot and immunohistochemistry analyses. The results of this study demonstrate that the association of diphenyl diselenide-supplemented diet and swimming exercise increased the levels of proteins involved in neuroprotection and decreased the activation of those related to apoptosis and neuroinflammation in the hippocampus of old rats. This study suggests that physical exercise and a diet supplemented with (PhSe)2 promoted neuroprotection in the hippocampus of aged rats. 相似文献
860.
Hianna Almeida Câmara Leite Anderson Barbosa Silva Fábio Pinto Gomes Karina Peres Gramacho José Cláudio Faria Jorge Teodoro de Souza Leandro Lopes Loguercio 《Applied microbiology and biotechnology》2013,97(6):2639-2651
Clonal genotypes resistant to fungal diseases are an important component of the cocoa production system in southeastern Bahia state (Brazil), so that technologies for faster production of stronger and healthier plantlets are highly desirable. In this study, the effects of inoculated bacterial endophytes isolated from healthy adult cacao plants on seedlings, and aspects related to inoculation methods, colonization patterns, and photosynthesis were investigated. Sequencing of 16S rRNA, hsp-60, and rpo-B genes placed the wild-type isolates within the species Enterobacter cloacae (isolates 341 and 344) and Bacillus subtilis (isolate 629). Spontaneous rifampicin-resistant (rifR) variants for 344 were also produced and tested. Endophytic application was either by immersion of surface sterilized seeds in bacterial suspensions or direct inoculation into soil, 20 days after planting non-inoculated seeds into pots. Results from in vitro recovery of inoculated isolates showed that the wild-type endophytes and rifR variants systemically colonized the entire cacao seedlings in 15–20 days, regardless of the inoculation method. Some endophytic treatments showed significant increases in seedlings’ height, number of leaves, and dry matter. Inoculation methods affected the combined application of endophytes, which maintained the growth-promotion effects, but not in the same manner as in single applications. Interestingly, the 344-3.2 rifR variant showed improved performance in relation to both the wild type and another related variant. Photosynthetic rates and stomatal conductance increased significantly for some endophytic treatments, being partially associated with effects on growth and affected by the inoculation method. The results suggest that E. cloacae and B. subtilis endophytes from healthy adult plants (not transmitted by seeds) were able to promote vegetative growth on cacao seedlings. The development of products for large-scale use in seedlings/plantlets production systems was discussed. 相似文献