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951.
Marcos Rogerio Rosa Aline Cristina Alves Diego Valverde Medeiros Ericka Oliveira Cavalcanti Coni Camilo Moitinho Ferreira Beatrice Padovani Ferreira Ricardo de Souza Rosa Gilberto Menezes Amado-Filho Guilherme Henrique Pereira-Filho Rodrigo Leão de Moura Fabiano Lopes Thompson Paulo Yukio Gomes Sumida Ronaldo Bastos Francini-Filho 《Coral reefs (Online)》2016,35(1):113-123
Mesophotic reef fish assemblages (30–90 m depth) of the small and remote St. Peter and St. Paul’s Archipelago (SPSPA), Mid-Atlantic Ridge, Brazil, were characterized using remotely operated vehicles. Ordination analyses identified distinct fish assemblages in the upper (30–50 m) and lower (50–90 m) mesophotic zones, the former characterized by high abundances of species that are also abundant at euphotic reefs (Caranx lugubris, Melichthys niger, Stegastes sanctipauli and Chromis multilineata) and the latter dominated by two mesophotic specialists (Prognathodes obliquus and Chromis enchrysura). Planktivores dominated fish assemblages, particularly in the upper mesophotic zone, possibly due to a greater availability of zooplankton coming from the colder Equatorial Undercurrent in mesophotic depths of the SPSPA. Turf algae, fleshy macroalgae and scleractinian corals dominated benthic assemblages between 30 and 40 m depth, while bryozoans, black corals and sponges dominated between 40 and 90 m depth. Canonical correspondence analysis explained 74 % of the relationship between environmental characteristics (depth, benthic cover and complexity) and structure of fish assemblages, with depth as the most important independent variable. Juveniles of Bodianus insularis and adults of P. obliquus and C. enchrysura were clearly associated with branching black corals (Tanacetipathes spp.), suggesting that black corals play key ecological roles in lower mesophotic reefs of the SPSPA. Results from this study add to the global database about mesophotic reef ecosystems (MREs) and provide a baseline for future evaluations of possible anthropogenic and natural disturbances on MREs of the SPSPA. 相似文献
952.
de Abreu Filipe Vieira Santos Macedo Mariana Viana da Silva Alex Junio Jardim de Oliveira Cirilo Henrique de Ottone Vinícius Oliveira de Almeida Marco Antônio Barreto dos Santos Edmilson da Cardoso Jader Cruz Campos Aline Scarpellini da Silva Claudia Maria Dornelles da Silva Amanda Gonzales de Andrade Miguel Souza Bernis Valéria Magro Octaviano Bernis Filho Walter Octaviano de Trindade Giliane Souza Albuquerque George Rego da Sevá Anaiá Paixão Ribeiro Bergmann Morais Teixeira Danilo Simonini Campos Fabrício Souza Franco Ana Cláudia Roehe Paulo Michel de Oliveira Danilo Bretas 《EcoHealth》2021,18(4):414-420
EcoHealth - In 2019, a new coronavirus disease (COVID-19) was detected in China. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was capable to infect domestic and captive mammals like... 相似文献
953.
Mariana J. Gomes Luana U. Pagan Aline R. R. Lima David R. A. Reyes Paula F. Martinez Felipe C. Damatto Thierres H. D. Pontes Eder A. Rodrigues Lidiane M. Souza Ingrid F. Tosta Ana A. H. Fernandes Leonardo A. M. Zornoff Katashi Okoshi Marina P. Okoshi 《Journal of cellular and molecular medicine》2020,24(9):5352-5362
We compared the influence of aerobic and resistance exercise on cardiac remodelling, physical capacity and skeletal muscle oxidative stress in rats with MI‐induced heart failure. Three months after MI induction, Wistar rats were divided into four groups: Sham; sedentary MI (S‐MI); aerobic exercised MI (A‐MI); and resistance exercised MI (R‐MI). Exercised rats trained three times a week for 12 weeks on a treadmill or ladder. Statistical analysis was performed by ANOVA or Kruskal‐Wallis test. Functional aerobic capacity was greater in A‐MI and strength gain higher in R‐MI. Echocardiographic parameters did not differ between infarct groups. Reactive oxygen species production, evaluated by fluorescence, was higher in S‐MI than Sham, and lipid hydroperoxide concentration was lower in A‐MI than the other groups. Glutathione peroxidase activity was higher in A‐MI than S‐MI and R‐MI. Superoxide dismutase was lower in S‐MI than Sham and R‐MI. Gastrocnemius cross‐sectional area, satellite cell activation and expression of the ubiquitin‐proteasome system proteins did not differ between groups. In conclusion, aerobic exercise and resistance exercise improve functional capacity and maximum load carrying, respectively, without changing cardiac remodelling in infarcted rats. In the gastrocnemius, infarction increases oxidative stress and changes antioxidant enzyme activities. Aerobic exercise reduces oxidative stress and attenuates superoxide dismutase and glutathione peroxidase changes. 相似文献
954.
Christian S. Adame Gonzlez Jos Trinidad lvarez Romero Mario Moranchel y Rodríguez Armando Flix Leyva Michelle Aline Villavicencio Queijeiro María Yicel Bautista Hernndez 《Reports of Practical Oncology and Radiotherapy》2021,26(5):664
BackgroundThe aim of the study was to Estimate and compare the radiobiological ratio α/β with the heuristic method for a cohort of Mexican patients with prostate cancer (PCa) who were treated with external radiotherapy (RT) techniques at three Hospital Institutions in Mexico City. With the Kaplan-Meier technique and the Cox proportional hazards model, the biochemical relapse-free survival (bRFS) is determined and characterized for cohorts of Mexican patients with PCa who received treatment with external RT. Using these clinical outcomes, the radiobiological parameter α/β is determined using the heuristic methodology of Pedicini et. al.Materials and methodsThe α/β is calculated from the survival curves for different treatment schemes implemented at three distinct hospitals. The Pedicini’s techniques allow to determine the parameters α/β, k and N0 when treatments are not radiobiologically equivalent, therefore, are built up of a set of curved pairs for the biologically effective dose (BED) versus the ratio α/β, where the ratio is given by the intersection for each pair of curves.ResultsSix different values of α/β were found: the first α/β = 2.46 Gy, the second α/β = 3.30 Gy, the third for α/β = 3.25 Gy, the fourth α/β = 3.24 Gy, the fifth α/β = 3.38 Gy and the last α/β = 4.08 Gy. These values can be explained as follows: a) The bRFS of the schemes presents a statistical variation; b) The absorbed doses given to the patient present uncertainties on the physical dosimetry that are not on the modeling; c) Finally, in the model for the bRFS of Eq. (3), there are parameters that have to be considered, such as: the number of clonogenic tumor cells N0, the overall treatment time (OTT), the kick-off time for tumor repopulation Tk and the repopulation doubling time. Therefore, the mean value to α/β for all schemes has an average value of 3.29 (± 0.52) Gy.ConclusionsThe value of is determined from cohorts of Mexican patients with PC a treated with external radiotherapy using the time-dependent LQ model, which is a higher value with respect to the “dogma” value of α/β 1.5 Gy obtained with the LQ model without temporal dependence. Therefore, there is a possibility of optimizing treatments radiobiologically and improving the results of bRFS in Mexican patients with PCa treated with external radiotherapy. 相似文献
955.
956.
Bernhard Jank Aline Berthold Sebastian Alber Otto Doblhoff-Dier 《The International Journal of Life Cycle Assessment》1999,4(5):251-252
The progression towards greater industrial sustainability involves the analysis of biotechnology as a means of achieving clean
or cleaner products and processes. Because living systems manage their chemistry more efficiently than man-made factories,
and their wastes tend to be recyclable and biodegradable, they can be expected to be more environmentally clean. Industry
has begun to use enzymes instead of traditional catalysts in many industrial production processes.
The future holds obstacles as well as opportunities for biotechnological applications. A greater ability to manipulate biological
materials and processes will have significant impact on manufacturing industries. A growing proportion of biotechnologyderived
processes and products is based on the use of genetically modified microorganisms. This extends the analysis from the aspect
of cleanliness to the aspect of safety. 相似文献
957.
Ziulkoski AL Zimmer AR Zanettini JS Trugo LC Guma FC 《Molecular and cellular biochemistry》2001,219(1-2):57-64
Cellular phospholipids of Sertoli cells from immature rats were labeled with [14C]-choline. Two sphingomyelin bands (SM1 and SM2) were identified by TLC. The incorporation of [14C]-choline over a 45 h period of incubation demonstrated that there are differences in labeling kinetics between SM1 and SM2. The subcellular location of SM1 and SM2 was investigated by accessibility to bacterial sphingomyelinase. The results showed the existence of two SM pools in Sertoli cells, but an equal cellular distribution of SM1 and SM2. SM2 is characterized by a relatively high content of unsaturated fatty acids. The inhibition of vesicular flow by monensin determines a decrease of about 60–70% in incorporation into SM1 and SM2, suggesting the existence of at least two sites of sphingomyelin synthesis. Pulse-chase and time-course experiments indicated a phosphatidylcholine SM precursor product relationship and differences in kinetic properties between SM1 and SM2. Resynthesis experiments showed that monensin had only a partial inhibitory effect on SM1 resynthesis, and a second sphingomyelinase treatment demonstrated that the resynthesized fraction reached the outer leaflet of the plasma membrane. The 60–70% inhibition of SM synthesis by monensin showed that the trans-Golgi cisternae and the trans-Golgi network are the most likely sites of bulk SM synthesis, and that about 15% of SM was synthesized in the cis/medial Golgi apparatus. Additionally the results indicated that plasma membrane SM synthase activity could be the site of about 15% of SM synthesis in Sertoli cells. 相似文献
958.
D. W. Rattner S. Ito M. J. Rutten W. Silen 《In vitro cellular & developmental biology. Plant》1985,21(8):453-462
Summary A method has been developed for growing confluent primary cultured monolayers of guinea pig gastric mucous cells suitable
for in vitro electrophysiological, transport, and pharmacological studies. Isolated mucous cells were enriched on a one-step
Percoll density gradient and plated on fibronectin-coated plastic dishes or in small cups with holes containing glutaraldehyde-fixed
Vitrogen gels. These cups were designed to fit in Ussing chambers. Mucous cells attached, proliferated, and formed confluent
monolayers in 3 d. The low cuboidal cells contained periodic acid Schiff-positive mucous granules that were negative by Bowie
and indirect immunofluorescent staining for pepsinogen. Electron microscopy revealed polarized mucous cells with microvilli,
mucous granules, microfilaments, small mitochondria, some vacuoles, and junctional complexes that excluded wheat germ agglutinin-peroxidase.
No basal lamina was present. Monolayers could be maintained for over 2 wk but subcultures were not made. The cultures were
virtually free of fibroblasts. Epithelial sheets produced by this simple and rapid method can be used for electrophysiological,
ion transport, and pharmacological studies.
This research was supported in part by National Institutes of Health grants GM7806, AM31158, AM 15681, and AM 30303. 相似文献
959.
960.
Letícia F. de Sousa Paulo E. de Menezes-Silva Lucas L. Lourenço Jeroni Galmés Aline C. Guimarães Aline F. da Silva Ana P. dos Reis Lima Liliane M. M. Henning Alan C. Costa Fabiano G. Silva Fernanda dos Santos Farnese 《Physiologia plantarum》2020,168(3):576-589
A variety of cellular responses is needed to ensure the plants survival during drought, but little is known about the signaling mechanisms involved in this process. Soybean cultivars (EMBRAPA 48 and BR 16, tolerant and sensitive to drought, respectively) were exposed to the following treatments: control conditions (plants in field capacity), drought (20% of available water in the soil), sodium nitroprusside (SNP) treatment (plants irrigated and treated with 100-µM SNP [SNP–nitric oxide (NO) donor molecule], and Drought + SNP (plants subjected to drought and SNP treatment). Plants remained in these conditions until the reproductive stage and were evaluated for physiological (photosynthetic pigments, chlorophyll a fluorescence and gas exchange rates), hydraulic (water potential, osmotic potential and leaf hydraulic conductivity) and morpho-anatomical traits (biomass, venation density and stomatal characterization). Exposure to water deficit considerably reduced water potential in both cultivars and resulted in decrease in photosynthesis and biomass accumulation. The addition of the NO donor attenuated these damaging effects of water deficit and increased the tolerance index of both cultivars. The results showed that NO was able to reduce plant's water loss, while maintaining their biomass production through alteration in stomatal characteristics, hydraulic conductivity and the biomass distribution pattern. These hydraulic and morpho-anatomical alterations allowed the plants to obtain, transport and lose less water to the atmosphere, even in water deficit conditions. 相似文献