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101.
Yen-Chin Liu Alice YW Chang Yu-Chuan Tsai Julie YH Chan 《Journal of biomedical science》2009,16(1):8-14
Background
Both overproduction of nitric oxide (NO) and oxidative injury of cardiovascular and pulmonary systems contribute to fatal cardiovascular depression during endotoxemia. We investigated in the present study the relative contribution of oxidative stress and NO to cardiovascular depression during different stages of endotoxemia, and delineated their roles in cardiovascular protective effects of a commonly used anesthetic propofol during endotoxemia. 相似文献102.
Alice Toso Simona Schifano Charlotte Oxborough Krista McGrath Luke Spindler Anabela Castro Lucy Evangelista Vanessa Filipe Maria José Gonçalves Antonio Marques Inês Mendes da Silva Raquel Santos Maria João Valente Iona McCleery Michelle Alexander 《American journal of physical anthropology》2021,176(2):208-222
103.
Stefan Caddy‐Retalic Alan N. Andersen Michael J. Aspinwall Martin F. Breed Margaret Byrne Matthew J. Christmas Ning Dong Bradley J. Evans Damien A. Fordham Greg R. Guerin Ary A. Hoffmann Alice C. Hughes Stephen J. van Leeuwen Francesca A. McInerney Suzanne M. Prober Maurizio Rossetto Paul D. Rymer Dorothy A. Steane Glenda M. Wardle Andrew J. Lowe 《Ecology and evolution》2017,7(13):4607-4619
Transects that traverse substantial climate gradients are important tools for climate change research and allow questions on the extent to which phenotypic variation associates with climate, the link between climate and species distributions, and variation in sensitivity to climate change among biomes to be addressed. However, the potential limitations of individual transect studies have recently been highlighted. Here, we argue that replicating and networking transects, along with the introduction of experimental treatments, addresses these concerns. Transect networks provide cost‐effective and robust insights into ecological and evolutionary adaptation and improve forecasting of ecosystem change. We draw on the experience and research facilitated by the Australian Transect Network to demonstrate our case, with examples, to clarify how population‐ and community‐level studies can be integrated with observations from multiple transects, manipulative experiments, genomics, and ecological modeling to gain novel insights into how species and systems respond to climate change. This integration can provide a spatiotemporal understanding of past and future climate‐induced changes, which will inform effective management actions for promoting biodiversity resilience. 相似文献
104.
Alice L. Hempel Patrick A. Reeves Richard G. Olmstead Robert K. Jansen 《Plant Systematics and Evolution》1995,194(1-2):25-37
Subclass and ordinal relationships ofLoasaceae, a small predominately New World family, are examined usingrbcL sequence data. Sequences were examined for eight of the fifteen genera of theLoasaceae and the morphologically anomalous aquatic genusHydrostachys (Hydrostachyaceae). Parsimony analyses of these sequences, combined with previously publishedrcbL data, indicate thatLoasaceae belong in theCornales, and are the sister group ofHydrangeaceae. This agrees with phylogenies based on chloroplast DNA inverted repeat restriction site, morphological and chemical data. TherbcL trees support the monophyly of theLoasaceae and most generic relationships correspond to current subfamily divisions. TherbcL phylogeny also provides the first suggestion thatHydrostachys is allied with theHydrangeaceae in theCornales. 相似文献
105.
Mello T Nakatsuka A Fears S Davis W Tsukamoto H Bosron WF Sanghani SP 《Biochemical and biophysical research communications》2008,374(3):460-464
Approximately 80% of the body vitamin A is stored in liver stellate cells with in the lipid droplets as retinyl esters. In low vitamin A status or after liver injury, stellate cells are depleted of the stored retinyl esters by their hydrolysis to retinol. However, the identity of retinyl ester hydrolase(s) expressed in stellate cells is unknown. The expression of carboxylesterase and lipase genes in purified liver cell-types was investigated by real-time PCR. We found that six carboxylesterase and hepatic lipase genes were expressed in hepatocytes. Adipose triglyceride lipase was expressed in Kupffer cells, stellate cells and endothelial cells. Lipoprotein lipase expression was detected in Kupffer cells and stellate cells. As a function of stellate cell activation, expression of adipose triglyceride lipase decreased by twofold and lipoprotein lipase increased by 32-fold suggesting that it may play a role in retinol ester hydrolysis during stellate cell activation. 相似文献
106.
Cell focal adhesions are micrometer-sized aggregates of proteins that anchor the cell to the extracellular matrix. Within the cell, these adhesions are connected to the contractile, actin cytoskeleton; this allows the adhesions to transmit forces to the surrounding matrix and makes the adhesion assembly sensitive to the rigidity of their environment. In this article, we predict the dynamics of focal adhesions as a function of the rigidity of the substrate. We generalize previous theories and include the fact that the dynamics of proteins that adsorb to adhesions are also driven by their coupling to cell contractility and the deformation of the matrix. We predict that adhesions reach a finite size that is proportional to the elastic compliance of the substrate, on a timescale that also scales with the compliance: focal adhesions quickly reach a relatively small, steady-state size on soft materials. However, their apparent sliding is not sensitive to the rigidity of the substrate. We also suggest some experimental probes of these ideas and discuss the nature of information that can be extracted from cell force microscopy on deformable substrates. 相似文献
107.
Qiu R Wang X Davy A Wu C Murai K Zhang H Flanagan JG Soriano P Lu Q 《The Journal of cell biology》2008,181(6):973-983
Maintaining a balance between self-renewal and differentiation in neural progenitor cells during development is important to ensure that correct numbers of neural cells are generated. We report that the ephrin-B-PDZ-RGS3 signaling pathway functions to regulate this balance in the developing mammalian cerebral cortex. During cortical neurogenesis, expression of ephrin-B1 and PDZ-RGS3 is specifically seen in progenitor cells and is turned off at the onset of neuronal differentiation. Persistent expression of ephrin-B1 and PDZ-RGS3 prevents differentiation of neural progenitor cells. Blocking RGS-mediated ephrin-B1 signaling in progenitor cells through RNA interference or expression of dominant-negative mutants results in differentiation. Genetic knockout of ephrin-B1 causes early cell cycle exit and leads to a concomitant loss of neural progenitor cells. Our results indicate that ephrin-B function is critical for the maintenance of the neural progenitor cell state and that this role of ephrin-B is mediated by PDZ-RGS3, likely via interacting with the noncanonical G protein signaling pathway, which is essential in neural progenitor asymmetrical cell division. 相似文献
108.
Maëva Luxey Thomas Jungas Julien Laussu Christophe Audouard Alain Garces Alice Davy 《Developmental biology》2013
Axon fasciculation is one of the processes controlling topographic innervation during embryonic development. While axon guidance steers extending axons in the accurate direction, axon fasciculation allows sets of co-extending axons to grow in tight bundles. The Eph:ephrin family has been involved both in axon guidance and fasciculation, yet it remains unclear how these two distinct types of responses are elicited. Herein we have characterized the role of ephrin-B1, a member of the ephrinB family in sensory and motor innervation of the limb. We show that ephrin-B1 is expressed in sensory axons and in the limb bud mesenchyme while EphB2 is expressed in motor and sensory axons. Loss of ephrin-B1 had no impact on the accurate dorso-ventral innervation of the limb by motor axons, yet EfnB1 mutants exhibited decreased fasciculation of peripheral motor and sensory nerves. Using tissue-specific excision of EfnB1 and in vitro experiments, we demonstrate that ephrin-B1 controls fasciculation of axons via a surround repulsion mechanism involving growth cone collapse of EphB2-expressing axons. Altogether, our results highlight the complex role of Eph:ephrin signaling in the development of the sensory-motor circuit innervating the limb. 相似文献
109.
Background
The Brief Infant-Toddler Social and Emotional Assessment (BITSEA) is a promising questionnaire for the early detection of psychosocial problems in toddlers. The screening accuracy and clinical application were evaluated.Methods
In a community sample of 2-year-olds (N = 2060), screening accuracy of the BITSEA Problem scale was examined regarding a clinical CBCL1.5-5 Total Problem score. For the total population and subgroups by child’s gender and ethnicity Receiver Operating Characteristic (ROC) curves were calculated, and across a range of BITSEA Problem scores, sensitivity, specificity, likelihood ratio’s, diagnostic odds ratio and Youden’s index. Clinical application of the BITSEA was examined by evaluating the relation between the scale scores and the clinical decision of the child health professional.Results
The area under the ROC curve (95% confidence interval) of the Problem scale was 0.97(0.95–0.98), there were no significant differences between subgroups. The association between clinical decision and BITSEA Problem score (B = 2.5) and Competence score (B = −0.7) was significant (p<0.05).Conclusions
The results indicate that the BITSEA Problem scale has good discriminative power to differentiate children with and without psychosocial problems. Referred children had less favourable scores compared to children that were not referred. The BITSEA may be helpful in the early detection of psychosocial problems. 相似文献110.
Lêda N. Regis Ridelane Veiga Acioli José Constantino Silveira Jr. Maria Alice Varjal Melo-Santos Wayner Vieira Souza Candida M. Nogueira. Ribeiro Juliana C. Serafim. da Silva Antonio Miguel Vieira Monteiro Cláudia M. F. Oliveira Rosangela M. R. Barbosa Cynthia Braga Marco Aurélio Benedetti Rodrigues Marilú Gomes N. M. Silva Paulo Justiniano Ribeiro Jr. Wagner Hugo Bonat Liliam César de Castro Medeiros Marilia Sa Carvalho André Freire Furtado 《PloS one》2013,8(7)
Aedes aegypti has developed evolution-driven adaptations for surviving in the domestic human habitat. Several trap models have been designed considering these strategies and tested for monitoring this efficient vector of Dengue. Here, we report a real-scale evaluation of a system for monitoring and controlling mosquito populations based on egg sampling coupled with geographic information systems technology. The SMCP-Aedes, a system based on open technology and open data standards, was set up from March/2008 to October/2011 as a pilot trial in two sites of Pernambuco -Brazil: Ipojuca (10,000 residents) and Santa Cruz (83,000), in a joint effort of health authorities and staff, and a network of scientists providing scientific support. A widespread infestation by Aedes was found in both sites in 2008–2009, with 96.8%–100% trap positivity. Egg densities were markedly higher in SCC than in Ipojuca. A 90% decrease in egg density was recorded in SCC after two years of sustained control pressure imposed by suppression of >7,500,000 eggs and >3,200 adults, plus larval control by adding fishes to cisterns. In Ipojuca, 1.1 million mosquito eggs were suppressed and a 77% reduction in egg density was achieved. This study aimed at assessing the applicability of a system using GIS and spatial statistic analysis tools for quantitative assessment of mosquito populations. It also provided useful information on the requirements for reducing well-established mosquito populations. Results from two cities led us to conclude that the success in markedly reducing an Aedes population required the appropriate choice of control measures for sustained mass elimination guided by a user-friendly mosquito surveillance system. The system was able to support interventional decisions and to assess the program’s success. Additionally, it created a stimulating environment for health staff and residents, which had a positive impact on their commitment to the dengue control program. 相似文献