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81.
Identification of a group of novel membrane proteins unique to chemosensory cilia of olfactory receptor cells 总被引:2,自引:0,他引:2
We have used a library of monoclonal antibodies (mAbs) against chemosensory cilia of the olfactory epithelium of Rana catesbeiana to identify proteins that are unique to the ciliary membrane. Five different antibodies (mAb 8, 26, 34, 42/45, and 43) identify novel proteins in olfactory cilia that are not detected in olfactory nerve membranes, nonchemosensory cilia from respiratory epithelium, or membranes from brain, heart, liver, kidney, and lung. Deglycosylation of olfactory cilia with endoglycosidase H shows that most of these antibodies (mAb 8, 42/45, 43, and possibly 26) react with antigenic determinants comprised partially or entirely of carbohydrate, while only one (mAb 34) recognizes an 87-kDa protein that is resistant to endoglycosidase H treatment. Furthermore, a 59-kDa glycoprotein visualized by mAb 8 exists as membrane-associated oligomers connected via intermolecular disulfide bonds. These proteins, tagged with distinct high-mannose-containing carbohydrate moieties and found only in chemosensory cilia of olfactory receptor cells, may be involved in odorant recognition and/or olfactory transduction. 相似文献
82.
Neil Brummitt Steven P. Bachman Elina Aletrari Helen Chadburn Janine Griffiths-Lee Maiko Lutz Justin Moat Malin C. Rivers Mindy M. Syfert Eimear M. Nic Lughadha 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2015,370(1662)
The IUCN Sampled Red List Index (SRLI) is a policy response by biodiversity scientists to the need to estimate trends in extinction risk of the world''s diminishing biological diversity. Assessments of plant species for the SRLI project rely predominantly on herbarium specimen data from natural history collections, in the overwhelming absence of accurate population data or detailed distribution maps for the vast majority of plant species. This creates difficulties in re-assessing these species so as to measure genuine changes in conservation status, which must be observed under the same Red List criteria in order to be distinguished from an increase in the knowledge available for that species, and thus re-calculate the SRLI. However, the same specimen data identify precise localities where threatened species have previously been collected and can be used to model species ranges and to target fieldwork in order to test specimen-based range estimates and collect population data for SRLI plant species. Here, we outline a strategy for prioritizing fieldwork efforts in order to apply a wider range of IUCN Red List criteria to assessments of plant species, or any taxa with detailed locality or natural history specimen data, to produce a more robust estimation of the SRLI. 相似文献
83.
Risk factors for cardiovascular disease including diabetes have seen a large rise in prevalence in recent years. This has prompted interest in prevention through the identifying individuals at risk of both diabetes and cardiovascular disease and has seen increased investment in screening interventions taking place in primary care. Community pharmacies have become increasingly involved in the provision of such interventions and this systematic review and meta-analysis aims to gather and analyse the existing literature assessing community pharmacy based screening for risk factors for diabetes and those with a high cardiovascular disease risk.
Methods
We conducted systematic searches of electronic databases using MeSH and free text terms from 1950 to March 2012. For our analysis two outcomes were assessed. They were the percentage of those screened who were referred for further assessment by primary care and the uptake of this referral.Results
Sixteen studies fulfilled our inclusion criteria comprising 108,414 participants screened. There was significant heterogeneity for all included outcomes. Consequently we have not presented summary statistics and present forest plots with I2 and p values to describe heterogeneity. We found that all included studies suffered from high rates of attrition between pharmacy screening and follow up. We have also identified a strong trend towards higher rates for referral in more recent studies.Conclusions
Our results show that pharmacies are feasible sites for screening for diabetes and those at risk of cardiovascular disease. A significant number of previously unknown cases of cardiovascular disease risk factors such as hypertension, hypercholesterolemia and diabetes are identified, however a significant number of referred participants at high risk do not attend their practitioner for follow up. Research priorities should include methods of increasing uptake to follow up testing and early intervention, to maximise the efficacy of screening interventions based in community pharmacies. 相似文献84.
ML Jones 《Biotechnic & histochemistry》2013,88(3):155-159
The discovery of formaldehyde for preserving tissue structures produced a new dimension in microscopy. Preserving structure and morphology became important; therefore, identifying a proper fixing agent for particular structures, chemical entities, and tissues, also became important. The methods for demonstrating tissue structures evolved and were implemented with careful observation and documentation of the results and outcomes. Formalin was incorporated into many techniques, and provided helpful results in many cases and hindrances in others. The effects of formalin on the outcomes of routine and special staining techniques are reported here. 相似文献
85.
86.
James W. Rivers Lynn B. Martin Andrea L. Liebl Matthew G. Betts 《Ethology : formerly Zeitschrift fur Tierpsychologie》2011,117(5):374-384
Alarm calling by parents is widespread among animals and has strong implications for parent and offspring fitness, yet it is virtually unknown whether parental alarm calls can initiate a corticosterone response in offspring. We investigated whether parental alarm calls of the white‐crowned sparrow, Zonotrichia leucophrys, activated the corticosterone response of their nest‐bound young, as such a response might prepare older nestlings for premature fledging and increase their survival when contacted by a predator at the nest. We conducted an experiment in which nestlings were either exposed to parent alarm calls (treatment) or experienced a period without parental alarm calls (control) immediately prior to blood sampling. We then sampled nestlings to measure corticosterone levels within 4 min of first contact (baseline corticosterone) and 60 min later (handling‐induced corticosterone). Young nestlings (i.e. 3–4 d post‐hatch) did not exhibit a corticosterone response to parental alarm calls or to handling, as mean corticosterone levels were similar in the control and treatment groups for both baseline and 60‐min post‐baseline samples. Against our predictions, there was no difference in mean levels of baseline corticosterone between control and treatment groups in older nestlings (i.e. 7?8 d post‐hatch) that were capable of surviving out of the nest. However, we did find a significant increase in mean levels of corticosterone after handling in both groups, which indicated that older nestlings were able to mount a functional corticosterone response when confronted with a potential predator. Why older nestlings did not initiate a corticosterone response after exposure to parental alarm calls is unclear but may have occurred because the costs of mounting such a response outweighed the benefits, perhaps because of growth or developmental costs. 相似文献
87.
Nitric oxide (NO) has been reported to act both as a destructive and a protective agent in the pathogenesis of the injuries
that occur during hypoxia/reoxygenation (H/R). It has been suggested that this dual role of NO depends directly on the isoform
of NO synthase (NOS) involved. In this work, we investigate the role that NO derived from endothelial NOS (eNOS) plays in
cardiac H/R-induced injury. Wistar rats were submitted to H/R (hypoxia for 30 min; reoxygenation of 0 h, 12 h and 5 days),
with or without prior treatment using the selective eNOS inhibitor l-NIO (20 mg/kg). Lipid peroxidation, apoptosis and protein nitration, as well as NO production (NOx), were analysed. The results
showed that l-NIO administration lowered NOx levels in all the experimental groups. However, no change was found in the lipid peroxidation
level, the percentage of apoptotic cells or nitrated protein expression, implying that eNOS-derived NO may not be involved
in the injuries occurring during H/R in the heart. We conclude that l-NIO would not be useful in alleviating the adverse effects of cardiac H/R. 相似文献
88.
Joseph M. Northrup James W. Rivers Zhiqiang Yang Matthew G. Betts 《Global Change Biology》2019,25(5):1561-1575
Climate and land‐use changes are expected to be the primary drivers of future global biodiversity loss. Although theory suggests that these factors impact species synergistically, past studies have either focused on only one in isolation or have substituted space for time, which often results in confounding between drivers. Tests of synergistic effects require congruent time series on animal populations, climate change and land‐use change replicated across landscapes that span the gradient of correlations between the drivers of change. Using a unique time series of high‐resolution climate (measured as temperature and precipitation) and land‐use change (measured as forest change) data, we show that these drivers of global change act synergistically to influence forest bird population declines over 29 years in the Pacific Northwest of the United States. Nearly half of the species examined had declined over this time. Populations declined most in response to loss of early seral and mature forest, with responses to loss of early seral forest amplified in landscapes that had warmed over time. In addition, birds declined more in response to loss of mature forest in areas that had dried over time. Climate change did not appear to impact populations in landscapes with limited habitat loss, except when those landscapes were initially warmer than the average landscape. Our results provide some of the first empirical evidence of synergistic effects of climate and land‐use change on animal population dynamics, suggesting accelerated loss of biodiversity in areas under pressure from multiple global change drivers. Furthermore, our findings suggest strong spatial variability in the impacts of climate change and highlight the need for future studies to evaluate multiple drivers simultaneously to avoid potential misattribution of effects. 相似文献
89.
Caunt CJ Rivers CA Conway-Campbell BL Norman MR McArdle CA 《The Journal of biological chemistry》2008,283(10):6241-6252
Spatiotemporal aspects of ERK activation are stimulus-specific and dictate cellular consequences. They are dependent upon dual specificity phosphatases (DUSPs) that bind ERK via docking domains and can both inactivate and anchor ERK in cellular compartments. Using high throughput fluorescence microscopy in combination with a system where endogenous ERKs are removed and replaced with wild-type or mutated ERK2-green fluorescent protein (GFP), we show that ERK2 activation responses to epidermal growth factor (EGF) and protein kinase C (PKC) are transient and sustained, respectively. PKC-mediated ERK2 activation is associated with prolonged nuclear localization in the dephosphorylated form, whereas EGF-stimulated ERK2 activation mediates only transient nuclear accumulation. By using short inhibitory RNAs to nuclear inducible DUSP1, -2, or -4 (alone or in combination), we demonstrate that all three of these enzymes contribute to the dephosphorylation of PKC (but not EGF)-activated ERK2 in the nucleus but that they have opposing effects on localization. DUSP2 and -4 inactivate and anchor ERK2, whereas DUSP1 dephosphorylates ERK in the nucleus but allows its traffic back to the cytoplasm. Overexpression of DUSP1, -2, or -4 prevented ERK2 activation, but only DUSP2 and -4 caused ERK2-GFP nuclear accumulation or could be immunoprecipitated with ERK2. Furthermore, protein synthesis inhibition or replacement of wild-type ERK2-GFP with docking domain mutants selectively increased PKC effects on ERK activity and altered ERK2-GFP localization. These mutations also impaired the ability of ERK2-GFP to bind DUSP2 and -4. Together, our data reveal a novel, stimulus-specific, and phosphatase-specific mechanism of ERK2 regulation in the nucleus by DUSP1, -2, and -4. 相似文献
90.