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991.
Elise P. Gomez-Sanchez Miriam T. Gomez-Sanchez Angela F. de Rodriguez Damian G. Romero Mary P. Warden Maria W. Plonczynski Celso E. Gomez-Sanchez 《The journal of histochemistry and cytochemistry》2009,57(7):633-641
An IHC survey using several monoclonal antibodies against different portions of the rat mineralocorticoid receptor (MR) molecule demonstrated significant specific MR immunoreactivity in the ovary, prompting further study of the localization of MR and of determinants of extrinsic MR ligand specificity, 11β-hydroxysteroid dehydrogenase (11β-HSD) types 1 and 2, and hexose-6-phosphate dehydrogenase (H6PDH). MR expression (real-time RT-PCR and Western blot) did not differ significantly in whole rat ovaries at early diestrus, late diestrus, estrus, and a few hours after ovulation. MR immunostaining was most intense in corporal lutea cells, light to moderate in oocytes and granulosa cells, and least intense in theca cells. Light immunoreactivity for 11β-HSD2 occurred in most cells, with some mural granulosa cells of mature follicles staining more strongly. The distribution of immunoreactivity for 11β-HSD1 and H6PDH required to generate NADPH, the cofactor required for reductase activity of 11β-HSD1, was similar, with the most-intense staining in the cytoplasm of corporal lutea and theca cells and light or no staining in the granulosa and oocytes. MR function in the ovary is as yet unclear, but distinct patterns of distribution of 11β-HSD1 and -2 and H6PDH suggest that the ligand for MR activation in different cells of the ovary may be differentially regulated. (J Histochem Cytochem 57:633–641, 2009) 相似文献
992.
993.
Pathophysiological significance of peroxidative stress, neuronal damage, and membrane permeability in acute mountain sickness. 总被引:10,自引:0,他引:10
Damian M Bailey Gian-Reto Kleger Manfred Holzgraefe Peter E Ballmer Peter B?rtsch 《Journal of applied physiology》2004,96(4):1459-1463
Free radical-mediated changes in vascular permeability and subsequent inflammatory response may be a contributory pathogenetic cofactor responsible for the development of neurological sequelae associated with acute mountain sickness (AMS). To investigate this, 49 subjects were examined at sea level and serially after rapid ascent to 4,559 m. Although the venous concentration of total creatine phosphokinase activity was measured in all subjects, a complementary examination of lipid peroxidation (F(2)-isoprostanes), inflammatory (TNF-alpha, IL-1beta, IL-2, IL-6, IL-8, C-reactive protein), and cerebrovascular tissue damage (neuron-specific enolase) biomarkers was confined to a subcohort of 24 subjects. A selective increase (P < 0.05) in total creatine phosphokinase was observed in subjects diagnosed with AMS at high altitude (n = 25) compared with apparently healthy controls (n = 24). However, despite a marked increase in IL-6 and C-reactive protein attributable primarily to subjects developing high-altitude pulmonary edema, subcohort analyses demonstrated no selective differences in F(2)-isoprostanes, neuron-specific enolase, or remaining proinflammatory cytokines due to AMS (n = 14). The present findings are the first to demonstrate that free radical-mediated neuronal damage of sufficient degree to be detected in the peripheral circulation does not occur and is, therefore, unlikely to be an important, initiating event that is critical for the development of AMS. The pathophysiological significance of increased sarcolemmal membrane permeability and inflammatory response, either as a cause or epiphenomenon of AMS and/or high-altitude pulmonary edema, remains to be elucidated. 相似文献
994.
995.
Delayed seed release (serotiny) is a convergent plant trait in fire-prone regions of the world but explaining the degree of serotiny has remained elusive because of the paucity of community data. Selective forces involving seed predators, fire and soil nutrients have been suggested as factors influencing serotiny. We tested whether protection of seeds and/or synchronized dispersal were associated with different levels of serotiny and if resprouting ability influences selection for strong serotiny. We compared the numbers and abundance of 146 woody species with delayed dispersal among five community types varying in combinations of fire severity, fire frequency, soil fertility and seed predators. The strength of the relationship between levels of serotiny and environmental factors was tested among community types ranging from rainforests to heathlands. Highest levels of serotiny were recorded in low nutrient shrublands with intermediate fire return intervals that burn at high severity, while the lowest were recorded in high nutrient, low flammability forests. Both protection of seeds and synchronized seed release were related to fire effects in nutrient-limited environments. Strong serotiny is prominent in species killed by fire whereas weak serotiny is more common in resprouting species. Recruitment failure in the inter-fire interval appears to drive selection for strong maternal care of seeds and synchronized seed dispersal in fire-prone environments. Weak serotiny is proposed as a bet-hedging strategy that relies on resprouting after fire for population persistence and higher probability of inter-fire recruitment. The spectrum of serotiny (weak to strong) in these communities is proposed to be driven by the interactive effect of both fire and soil nutrients on the selection for delayed seed dispersal. 相似文献
996.
Marjorie L. Prokosch Zachary Airington Damian R. Murray 《Evolution and human behavior》2021,42(2):113-120
Although humans' sense of smell is relatively diminished compared to other species, olfaction is still a central sensory modality through which people evaluate both potential threats and prospective romantic partners. Despite olfaction's role in interpersonal relationships and disease avoidant responses, however, it remains unknown whether variation in olfactory acuity is associated with disease- and mating-relevant psychological constructs and behaviors. In the current exploratory study, we examined the relationships between olfactory acuity, disgust sensitivity, and mating strategies in a sample of undergraduate students (N = 162) at a university in the Southern United States using an extended assessment of olfactory acuity (measuring olfactory threshold, discrimination, and identification). Results revealed that people with greater discrimination acuity were higher in dispositional sexual disgust, but not pathogen or moral disgust. People with greater discrimination acuity were also less inclined towards short-term mating. Further, sexual disgust mediated the relationship between discrimination acuity and short-term mating orientation. These results provide further evidence for the importance of olfaction and olfaction-related disgust in close relationships. 相似文献
997.
Anette Schneemann Jeffrey A. Speir Gene S. Tan Reza Khayat Damian C. Ekiert Yumiko Matsuoka Ian A. Wilson 《Journal of virology》2012,86(21):11686-11697
The discovery of broadly neutralizing antibodies that recognize highly conserved epitopes in the membrane-proximal region of influenza virus hemagglutinin (HA) has revitalized efforts to develop a universal influenza virus vaccine. This effort will likely require novel immunogens that contain these epitopes but lack the variable and immunodominant epitopes located in the globular head of HA. As a first step toward developing such an immunogen, we investigated whether the 20-residue A-helix of the HA2 chain that forms the major component of the epitope of broadly neutralizing antibodies CR6261, F10, and others is sufficient by itself to elicit antibodies with similarly broad antiviral activity. Here, we report the multivalent display of the A-helix on icosahedral virus-like particles (VLPs) derived from the capsid of Flock House virus. Mice immunized with VLPs displaying 180 copies/particle of the A-helix produced antibodies that recognized trimeric HA and the elicited antibodies had binding characteristics similar to those of CR6261 and F10: they recognized multiple HA subtypes from group 1 but not from group 2. However, the anti-A-helix antibodies did not neutralize influenza virus. These results indicate that further engineering of the transplanted peptide is required and that display of additional regions of the epitope may be necessary to achieve protection. 相似文献
998.
Żaneta Kałuzińska-Kołat Damian Kołat Katarzyna Kośla Elżbieta Płuciennik rzej K Bednarek 《World journal of stem cells》2023,15(5):302-322
Literature data on glioblastoma ongoingly underline the link between metabolism and cancer stemness, the latter is one responsible for potentiating the resistance to treatment, inter alia due to increased invasiveness. In recent years, glioblastoma stemness research has bashfully introduced a key aspect of cytoskeletal rearrangements, whereas the impact of the cytoskeleton on invasiveness is well known. Although non-stem glioblastoma cells are less invasive than glioblastoma stem cells (GSCs), these cells also acquire stemness with greater ease if characterized as invasive cells and not tumor core cells. This suggests that glioblastoma stemness should be further investigated for any phenomena related to the cytoskeleton and metabolism, as they may provide new invasion-related insights. Previously, we proved that interplay between metabolism and cytoskeleton existed in glioblastoma. Despite searching for cytoskeleton-related processes in which the investigated genes might have been involved, not only did we stumble across the relation to metabolism but also reported genes that were found to be implicated in stemness. Thus, dedicated research on these genes in GSCs seems justifiable and might reveal novel directions and/or biomarkers that could be utilized in the future. Herein, we review the previously identified cyto skeleton/metabolism-related genes through the prism of glioblastoma stemness. 相似文献
999.
George Kessie Damian M. Dela Cruz Mohamed A. Taha Fahad J. Al-Shammary Abdulkadir F. Tawfik Mohammed N. Al-Ahdal 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1994,652(2)
[35S]Methionine-labelled envelope polypeptides of Herpes simplex virus type 1, strain F, propagated in mammalian cell culture of various origins, were separated by ion-exchange high-performance liquid chromatography on a TSK DEAE-3SW column. Analysis of the fractions by radioimmunoprecipitation followed by sodium dodecyl sulphate polyacrylamide gel electrophoresis of the immunoprecipitates showed similarities as well as distinct differences in the number, migration patterns and molecular mass of the synthesized polypeptides, depending on the host cell. The results show that this method can be used to demonstrate species-specific or organ-specific differences in the processing of virus-specified polypeptides synthesized in host cells. 相似文献
1000.
Mitchell A. Cowan Michael N. Callan Maggie J. Watson David M. Watson Tim S. Doherty Damian R. Michael Judy A. Dunlop James M. Turner Harry A. Moore Darcy J. Watchorn Dale G. Nimmo 《Biological reviews of the Cambridge Philosophical Society》2021,96(6):2735-2754
Artificial refuges are human-made structures that aim to create safe places for animals to breed, hibernate, or take shelter in lieu of natural refuges. Artificial refuges are used across the globe to mitigate the impacts of a variety of threats on wildlife, such as habitat loss and degradation. However, there is little understanding of the science underpinning artificial refuges, and what comprises best practice for artificial refuge design and implementation for wildlife conservation. We address this gap by undertaking a systematic review of the current state of artificial refuge research for the conservation of wildlife. We identified 224 studies of artificial refuges being implemented in the field to conserve wildlife species. The current literature on artificial refuges is dominated by studies of arboreal species, primarily birds and bats. Threatening processes addressed by artificial refuges were biological resource use (26%), invasive or problematic species (20%), and agriculture (15%), yet few studies examined artificial refuges specifically for threatened (Vulnerable, Endangered, or Critically Endangered) species (7%). Studies often reported the characteristics of artificial refuges (i.e. refuge size, construction materials; 87%) and surrounding vegetation (35%), but fewer studies measured the thermal properties of artificial refuges (18%), predator activity (17%), or food availability (3%). Almost all studies measured occupancy of the artificial refuges by target species (98%), and over half measured breeding activity (54%), whereas fewer included more detailed measures of fitness, such as breeding productivity (34%) or animal body condition (4%). Evaluating the benefits and impacts of artificial refuges requires sound experimental design, but only 39% of studies compared artificial refuges to experimental controls, and only 10% of studies used a before-after-control-impact (BACI) design. As a consequence, few studies of artificial refuges can determine their overall effect on individuals or populations. We outline a series of key steps in the design, implementation, and monitoring of artificial refuges that are required to avoid perverse outcomes and maximise the chances of achieving conservation objectives. This review highlights a clear need for increased rigour in studies of artificial refuges if they are to play an important role in wildlife conservation. 相似文献