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971.
George Amaro Elisangela Gomes Fidelis de Morais 《Experimental & applied acarology》2013,60(3):343-355
Among pests that have recently been introduced into the Americas, the red palm mite, Raoiella indica Hirst (Prostigmata: Tenuipalpidae), is the most invasive. This mite has spread rapidly to several Caribbean countries, United States of America, Mexico, Venezuela, Colombia and Brazil. The potential dispersion of R. indica to other regions of South America could seriously impact the cultivation of coconuts, bananas, exotic and native palms and tropical flowers such as the Heliconiaceae. To facilitate the development of efficacious R. indica management techniques such as the adoption of phytosanitary measures to prevent or delay the dispersion of this pest, the objective of this paper was to estimate the potential geographical distribution of R. indica in South America using a maximum entropy model. The R. indica occurrence data used in this model were obtained from extant literature, online databases and field sampling data. The model predicted potential suitable areas for R. indica in northern Colombia, central and northern Venezuela, Guyana, Suriname, east French Guiana and many parts of Brazil, including Roraima, the eastern Amazonas, northern Pará, Amapá and the coastal zones, from Pará to north of Rio de Janeiro. These results indicate the potential for significant R. indica related economic and social impacts in all of these countries, particularly in Brazil, because the suitable habitat regions overlap with agricultural areas for R. indica host plants such as coconuts and bananas. 相似文献
972.
Mariska Batavia George Nguyen Kristine Harman Irving Zucker 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》2013,183(2):269-277
Turkish hamsters (Mesocricetus brandti) are a model organism for studies of hibernation, yet a detailed account of their torpor characteristics has not been undertaken. This study employed continuous telemetric monitoring of body temperature (T b) in hibernating male and female Turkish hamsters at ambient temperatures (T as) of 5 and 13 °C to precisely characterize torpor bout depth, duration, and frequency, as well as rates of entry into and arousal from torpor. Hamsters generated brief intervals of short (<12 h), shallow test bouts (T b > 20 °C), followed by deep torpor bouts lasting 4–6 days at T a = 5 °C and 2–3 days at T a = 13 °C. Females at T a = 5 °C had longer bouts than males, but maintained higher torpor T b; there were no sex differences at T a = 13 °C. Neither body mass loss nor food intake differed between the two T as. Hamsters entered torpor primarily during the scotophase (subjective night), but timing of arousals was highly variable. Hamsters at both T as generated short, shallow torpor bouts between deep bouts, suggesting that this species may be capable of both hibernation and daily torpor. 相似文献
973.
T. Mitchell Aide Matthew L. Clark H. Ricardo Grau David López‐Carr Marc A. Levy Daniel Redo Martha Bonilla‐Moheno George Riner María J. Andrade‐Núñez María Muñiz 《Biotropica》2013,45(2):262-271
Forest cover change directly affects biodiversity, the global carbon budget, and ecosystem function. Within Latin American and the Caribbean region (LAC), many studies have documented extensive deforestation, but there are also many local studies reporting forest recovery. These contrasting dynamics have been largely attributed to demographic and socio‐economic change. For example, local population change due to migration can stimulate forest recovery, while the increasing global demand for food can drive agriculture expansion. However, as no analysis has simultaneously evaluated deforestation and reforestation from the municipal to continental scale, we lack a comprehensive assessment of the spatial distribution of these processes. We overcame this limitation by producing wall‐to‐wall, annual maps of change in woody vegetation and other land‐cover classes between 2001 and 2010 for each of the 16,050 municipalities in LAC, and we used nonparametric Random Forest regression analyses to determine which environmental or population variables best explained the variation in woody vegetation change. Woody vegetation change was dominated by deforestation (?541,835 km2), particularly in the moist forest, dry forest, and savannas/shrublands biomes in South America. Extensive areas also recovered woody vegetation (+362,430 km2), particularly in regions too dry or too steep for modern agriculture. Deforestation in moist forests tended to occur in lowland areas with low population density, but woody cover change was not related to municipality‐scale population change. These results emphasize the importance of quantitating deforestation and reforestation at multiple spatial scales and linking these changes with global drivers such as the global demand for food. 相似文献
974.
It has been difficult to examine the role of TGF-ß in post-natal tooth development due to perinatal lethality in many of the signaling deficient mouse models. To address the role of Tgfbr2 in postnatal tooth development, we generated a mouse in which Tgfbr2 was deleted in odontoblast- and bone-producing mesenchyme. Osx-Cre;Tgfbr2fl/fl mice were generated (Tgfbr2cko) and post-natal tooth development was compared in Tgfbr2cko and control littermates. X-ray and μCT analysis showed that in Tgfbr2cko mice radicular dentin matrix density was reduced in the molars. Molar shape was abnormal and molar eruption was delayed in the mutant mice. Most significantly, defects in root formation, including failure of the root to elongate, were observed by postnatal day 10. Immunostaining for Keratin-14 (K14) was used to delineate Hertwig's epithelial root sheath (HERS). The results showed a delay in elongation and disorganization of the HERS in Tgfbr2cko mice. In addition, the HERS was maintained and the break up into epithelial rests was attenuated suggesting that Tgfbr2 acts on dental mesenchyme to indirectly regulate the formation and maintenance of the HERS. Altered odontoblast organization and reduced Dspp expression indicated that odontoblast differentiation was disrupted in the mutant mice likely contributing to the defect in root formation. Nevertheless, expression of Nfic, a key mesenchymal regulator of root development, was similar in Tgfbr2cko mice and controls. The number of osteoclasts in the bone surrounding the tooth was reduced and osteoblast differentiation was disrupted likely contributing to both root and eruption defects. We conclude that Tgfbr2 in dental mesenchyme and bone is required for tooth development particularly root formation. 相似文献
975.
976.
Adriana Simionescu-Bankston Giovanna Leoni Yanru Wang Peter P. Pham Arivudainambi Ramalingam James B. DuHadaway Victor Faundez Asma Nusrat George C. Prendergast Grace K. Pavlath 《Developmental biology》2013
Actin dynamics are necessary at multiple steps in the formation of multinucleated muscle cells. BAR domain proteins can regulate actin dynamics in several cell types, but have been little studied in skeletal muscle. Here, we identify novel functions for the N-BAR domain protein, Bridging integrator 3 (Bin3), during myogenesis in mice. Bin3 plays an important role in regulating myofiber size in vitro and in vivo. During early myogenesis, Bin3 promotes migration of differentiated muscle cells, where it colocalizes with F-actin in lamellipodia. In addition, Bin3 forms a complex with Rac1 and Cdc42, Rho GTPases involved in actin polymerization, which are known to be essential for myotube formation. Importantly, a Bin3-dependent pathway is a major regulator of Rac1 and Cdc42 activity in differentiated muscle cells. Overall, these data classify N-BAR domain proteins as novel regulators of actin-dependent processes in myogenesis, and further implicate BAR domain proteins in muscle growth and repair. 相似文献
977.
Dessislava Staneva Ekaterina Peycheva Milena Georgieva Toni Efremov George Miloshev 《Antonie van Leeuwenhoek》2013,103(1):143-152
Kluyveromyces lactis, also known as dairy yeast, has numerous applications in scientific research and practice. It has been approved as a GRAS (Generally Recognized As Safe) organism, a probiotic, a biotechnological producer of important enzymes at industrial scale and a bioremediator of waste water from the dairy industry. Despite these important practical applications the sensitivity of this organism to genotoxic substances has not yet been assessed. In order to evaluate the response of K. lactis cells to genotoxic agents we have applied several compounds with well-known cyto- and genotoxic activity. The method of comet assay (CA) widely used for the assessment of DNA damages is presented here with new special modifications appropriate for K. lactis cells. The comparison of the response of K. lactis to genotoxins with that of Saccharomyces cerevisiae showed that both yeasts, although considered close relatives, exhibit species-specific sensitivity toward the genotoxins examined. 相似文献
978.
Yonatan B. Tzur Ari E. Friedland Saravanapriah Nadarajan George M. Church John A. Calarco Monica P. Colaiácovo 《Genetics》2013,195(3):1181-1185
We adapted the CRISPR–Cas9 system for template-mediated repair of targeted double-strand breaks via homologous recombination in Caenorhabditis elegans, enabling customized and efficient genome editing. This system can be used to create specific insertions, deletions, and base pair changes in the germline of C. elegans. 相似文献
979.
Magali Moreau Timothy Westlake Giulio Zampogna George Popescu Miaoying Tian Christos Noutsos Sorina Popescu 《The Plant journal : for cell and molecular biology》2013,76(4):603-614
Salicylic acid (SA) is a small phenolic molecule with hormonal properties, and is an essential component of the immune response. SA exerts its functions by interacting with protein targets; however, the specific cellular components modulated by SA and critical for immune signal transduction are largely unknown. To uncover cellular activities targeted by SA, we probed Arabidopsis protein microarrays with a functional analog of SA. We demonstrate that thimet oligopeptidases (TOPs) constitute a class of SA‐binding enzymes. Biochemical evidence demonstrated that SA interacts with TOPs and inhibits their peptidase activities to various degrees both in vitro and in plant extracts. Functional characterization of mutants with altered TOP expression indicated that TOP1 and TOP2 mediate SA‐dependent signaling and are necessary for the immune response to avirulent pathogens. Our results support a model whereby TOP1 and TOP2 act in separate pathways to modulate SA‐mediated cellular processes. 相似文献
980.
Shyh-Ming Yang Yuting Tang Rui Zhang Huajun Lu Gee-Hong Kuo Michael D. Gaul Yaxin Li George Ho James G. Conway Yin Liang James M. Lenhard Keith T. Demarest William V. Murray 《Bioorganic & medicinal chemistry letters》2013,23(24):6773-6776
A new series of urea-based, 4-bicyclic heteroaryl-piperidine derivatives as potent SCD1 inhibitors is described. The structure–activity relationships focused on bicyclic heteroarenes and aminothiazole–urea portions are discussed. A trend of dose-dependent decrease in body weight gain in diet-induced obese (DIO) mice is also demonstrated. 相似文献