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991.
Cristobal G. dos Remedios 《Biophysical reviews》2018,10(4):1201-1203
In 2017, a Special Issue of Biophysical Reviews was devoted to “Titin and Its Binding Partners. The issue contained a review: “An historical perspective of the discovery of titin filaments” by dos Remedios and Gilmour that was intended to be a history of the discovery of the giant protein titin, previously named connectin. The review took readers back to the earliest discovery of the so-called third filament component of skeletal and cardiac muscle sarcomeres and ended in 1969. Recently, my colleague Shin’ichi Ishiwata gently reminded me of two papers published in 1990 and 1993 that were unwittingly omitted from the original historical perspective. In the first paper (J Cell Biol 110:53–62, 1990), Funatsu et al. examined the elastic filaments in skeletal muscle using a combination of light and electron microscopy, but they also measured resting as well as passive stiffness mechanical measurements to establish that connectin (titin) is responsible for both stiffness and fiber tension. In the second paper (J Cell Biol 120:711–724, 1993), Funatsu et al. used permeabilised cardiac muscle myocytes (from rabbit papillary muscles) and focussed on filament ultrastructure using either freeze-substitution or deep-etched replica methods to visualise connectin/titin filaments in fibers with and without actin and myosin filaments. 相似文献
992.
Carlos E. Santos Cecilia Menjívar Rachel A. VanDaalen Olga Kornienko Kimberly A. Updegraff Samantha Cruz 《Ethnic and racial studies》2018,41(9):1672-1690
Bridging diverse areas of inquiry (i.e. legal studies and developmental psychology), this study explored the longitudinal association between Latina/o youths’ burgeoning legal consciousness, measured as awareness of Senate Bill 1070 (SB1070) in Arizona, and their adjustment in school, measured as classroom regulatory behaviours, and examined whether this association varied across immigrant generational status and gender. Participants were 689 Latina/o middle school students in Arizona (Mage?=?12.06 years, SD?=?.98). Multiple regression analysis revealed a significant interaction between Latina/o youths’ awareness of SB1070 at Time 1 and gender in predicting classroom regulatory behaviours at Time 2 (controlling for levels of it at Time 1). Males who were higher on awareness of SB1070 at Time 1 reported lower levels of classroom regulatory behaviours at Time 2. This study underscores the importance of measuring youths’ awareness of laws and how this awareness may impact their academic adjustment. 相似文献
993.
Alysson Wagner Fernandes Duarte Juliana Aparecida dos Santos Marina Vitti Vianna Juliana Maíra Freitas Vieira Vitor Hugo Mallagutti Fabio José Inforsato 《Critical reviews in biotechnology》2018,38(4):600-619
Antarctica is the coldest, windiest, and driest continent on Earth. In this sense, microorganisms that inhabit Antarctica environments have to be adapted to harsh conditions. Fungal strains affiliated with Ascomycota and Basidiomycota phyla have been recovered from terrestrial and marine Antarctic samples. They have been used for the bioprospecting of molecules, such as enzymes. Many reports have shown that these microorganisms produce cold-adapted enzymes at low or mild temperatures, including hydrolases (e.g. α-amylase, cellulase, chitinase, glucosidase, invertase, lipase, pectinase, phytase, protease, subtilase, tannase, and xylanase) and oxidoreductases (laccase and superoxide dismutase). Most of these enzymes are extracellular and their production in the laboratory has been carried out mainly under submerged culture conditions. Several studies showed that the cold-adapted enzymes exhibit a wide range in optimal pH (1.0–9.0) and temperature (10.0–70.0?°C). A myriad of methods have been applied for cold-adapted enzyme purification, resulting in purification factors and yields ranging from 1.70 to 1568.00-fold and 0.60 to 86.20%, respectively. Additionally, some fungal cold-adapted enzymes have been cloned and expressed in host organisms. Considering the enzyme-producing ability of microorganisms and the properties of cold-adapted enzymes, fungi recovered from Antarctic environments could be a prolific genetic resource for biotechnological processes (industrial and environmental) carried out at low or mild temperatures. 相似文献
994.
995.
Using antagonistic soil bacteria and their cell‐free filtrates to control the black rot pathogen Xanthomonas campestris pv. campestris 下载免费PDF全文
Rafael S. da Silva Brenda L. Moutinho Deise R. dos Santos I. S. Vasconcelo‐Rodrigues Viviane Talamini Marcelo F. Fernandes Roberta P. M. Fernandes 《Journal of Phytopathology》2018,166(7-8):494-501
Xanthomonas campestris pv. campestris (Xcc) is a phytopathogenic bacteria, and it is the causative agent of black rot in crucifers. Recent studies have shown that Bacillus species have strong biological control on Xanthomonas. One of the mechanisms of this control is secondary metabolites production. A collection of 257 bacteria isolated from a suppressive soil was evaluated for in vitro antagonistic activity against X. campestris, and 92 isolates (44.6%) were able to inhibit its growth. Among the 92 isolates evaluated in the double‐layer technique, 51 (55.43%) inhibited Xcc growth on the inhibition tests with cell‐free filtrates (CFF) in liquid medium. Thirteen of these isolates presented 50% or more growth inhibition, and five isolates presented 100% growth inhibition of Xcc. The CFF of the isolate TCDT‐08, which belongs to the Paenibacillus genus, was used for in vivo tests with kale crops. The artificial inoculation of kale with Xcc‐629IBSBF pretreated with CFF from the isolate TCDT‐08 demonstrated that the bacterium loses the ability of colonizing kale and of causing black rot. A Paenibacillus sp. isolate has strong inhibitory activity against X. campestris pv. campestris, and further studies can result in the use of this isolate to protect kale from Xcc infection. 相似文献
996.
Roberta Fernanda Ventura Cerqueira Flávia Carolina Simões-Gomes Yrllan Ribeiro Sincurá Thiago Santos 《Studies on Neotropical Fauna and Environment》2018,53(2):85-90
A study of the phlebotomine sand fly fauna was carried out in the Rio Preto State Park (Minas Gerais, Brazil) aiming to associate the presence of vector species with the risk of leishmaniasis transmission in that region. Sand flies were captured using HP light traps for four months from January to October 2013. The traps were exposed continuously for 40 h each month, in nine fixed sites. A total of 3129 sand flies were captured, belonging to 19 species. Lutzomyia evandroi (Costa Lima & Antunes 1936) was the predominant species (76.48%). The distribution of the phlebotomine sand flies and climatic factors (temperature, humidity, and rainfall) was evaluated. The summer was the season with higher occurrence of insects captured (82.4%). The presence of cutaneous and visceral vector species in park areas requires attention and regular monitoring of sand fly fauna in this conservation area to ensure the well-being of visitors and the regional ecotourism. 相似文献
997.
Marcos Antônio Melo Daniele Janina Moreno Bianca Costa Ribeiro Paulo Guilherme Bisetto de Andrade Anelisa Ferreira de Almeida Magalhães Maria Amélia Santos de Carvalho 《Studies on Neotropical Fauna and Environment》2018,53(2):162-166
Mist netting is the most popular method for capturing birds, but it can increase the predation rates of individuals trapped in the nets. From 2008 to 2017, we recorded eight instances of opportunistic bird predation from mist nets (MNs) in a matrix mixing restored forest and fragments of semideciduous seasonal forest in southeastern Brazil, three times (37.5%) by exotic primates and five times (62.5%) by birds of prey. Overall predation rates (1.17–1.20%) at these two sites were considered high but were lower than in other Brazilian studies. Placing MNs near the edges of forest fragments may have allowed attacks by either forest predators or marmosets, which are exotic edge species. Some previously described precautions may decrease the predation rates of birds in MNs, such as shorter observation intervals, greater attention to given site selection and maintaining a safe distance between the MNs and the ground. 相似文献
998.
Co-production of carotenoids and xylitol by Xanthophyllomyces dendrorhous (Phaffia rhodozyma) 总被引:1,自引:0,他引:1
Carotenoid production by Xanthophyllomyces dendrorhous (formerly Phaffia rhodozyma) when growing on xylose depended on the initial substrate concentration. Astaxanthin was the main carotenoid, others were echinenone, 3-hydroxyechinenone and canthaxanthin. Xylitol (an intermediate of xylose metabolism, with application as sweetener) accumulates in the fermentation media. Xylitol concentrations up to 22 g/l were obtained in experiments carried out with an initial xylose concentration of 42 g/l. Xylitol was assimilated after xylose depletion. 相似文献
999.
Evaluation of cDNA Libraries from Different Developmental Stages of Schistosoma mansoni for Production of Expressed Sequence Tags (ESTs) 总被引:9,自引:0,他引:9
Franco Gloria R.; Rabelo Elida M. L.; Azevedo Vasco; Pena Heloisa B.; Ortega J. Miguel; Santos Tulio M.; Meira Wendell S. F.; Rodrigues Neuza A.; Dias Carlos M. M.; Harrop Richard; Wilson Alan; Saber Mohamed; Abdel-Hamid Hannan; Faria Michelyne S. C.; Margutti Maria Elizabeth B.; Parra Jucara C.; Pena Seergio D. J. 《DNA research》1997,4(3):231-240
A comparative study of the gene expression profile in differentdevelopmental stages of Schistosoma mansoni has been initiatedbased on the expressed sequence tag(EST) approach. A total of1401 ESTs were generated from seven different cDNA librariesconstructed from four distinct stages of the parasite life cycle.The libraries were first evaluated for their quality for a large-scalecDNA sequencing program. Most of them were shown to have lessthan 20% useless clones and more than 50% new genes. The redundancyof each library was also analyzed, showing that one adult wormcDNA library was composed of a small number of highly frequentgenes. When comparing ESTs from distinct libraries, we coulddetect that most genes were present only in a single library,but others were expressed in more than one developmental stageand may represent housekeeping genes in the parasite. When consideringonly once the genes present in more than one library, a totalof 466 unique genes were obtained, corresponding to 427 newS. mansoni genes. From the total of unique genes, 20.2% wereidentified based on homology with genes from other organisms,8.3% matched S. mansoni characterized genes and 71.5% representunknown genes. 相似文献
1000.