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151.
Reviews in Fish Biology and Fisheries - Since 2015, the European Union gradually implemented the landing obligation (LO). This prohibits at-sea discarding of species under total allowable catch...  相似文献   
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153.
Age-related disease, not aging per se, causes most morbidity in older humans. Here we report that skeletal muscle respiratory uncoupling due to UCP1 expression diminishes age-related disease in three mouse models. In a longevity study, median survival was increased in UCP mice (animals with skeletal muscle-specific UCP1 expression), and lymphoma was detected less frequently in UCP female mice. In apoE null mice, a vascular disease model, diet-induced atherosclerosis was decreased in UCP animals. In agouti yellow mice, a genetic obesity model, diabetes and hypertension were reversed by induction of UCP1 in skeletal muscle. Uncoupled mice had decreased adiposity, increased temperature and metabolic rate, elevated muscle SIRT and AMP kinase, and serum characterized by increased adiponectin and decreased IGF-1 and fibrinogen. Accelerating metabolism in skeletal muscle does not appear to impact aging but may delay age-related disease.  相似文献   
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155.
Calmidazolium {R24571, 1-[bis(4-chlorophenyl)methyl]-3-[2-(2,4-dichlorophenyl)-2-[(2,4-dichlorophenyl)methoxy]ethyl]-1H-imidazolium chloride} is a potent calmodulin inhibitor. This paper describes the synthesis and properties of the enantiomers of calmidazolium from the enantiomers of miconazole {1(N)-(2-(2,4-dichlorobenzyloxy)-2-(2,4-dichlorophenyl))-ethyl imidazole}, prepared from the racemate by chiral preparative scale high performance liquid chromatography. Overlap between ligand and protein resonances in the aromatic region of the 1H NMR spectrum of the calmidazolium-calmodulin complexes has been obviated by preparation of the protein with all of its nine phenylalanine rings deuterated (Phe-d5 calmodulin). This has been accomplished by the overexpression of calmodulin derived from Trypanosoma brucei rhodiesiense in E. coli in a medium supplemented with ring-deuterated phenylalanine. The kinetics of binding of each enantiomer are slow on the 1H NMR time scale as judged by the behaviour of the H2 resonance of Histidine-107, which is clearly visible under the sample conditions used. The aromatic spectral regions of the protein-bound (+) and (−) enantiomers contrast strikingly, reflecting differences in bound environment and/or conformation. Chirality 8:545–500, 1996. © 1997 Wiley-Liss, Inc.  相似文献   
156.
M J Miller  K Shannon  M B Reid 《Life sciences》1989,45(25):2419-2428
The isometric contractile response of the directly-stimulated rat diaphragm was studied before and following addition of the calcium channel blocker, nifedipine. Nifedipine (10 micrograms/ml and 30 micrograms/ml bath concentrations) significantly increased isometric force output during twitch and unfused tetanic stimulation. Force potentiation during unfused tetanic stimulation was equivalent during either high or low voltage stimulation. Nifedipine had no effect on the time to peak force, half relaxation time, or relaxation time during twitch stimulation; thus, both activation and relaxation rates were increased. The force potentiating actions of nifedipine persisted in a calcium-free bathing solution and were enhanced by d-tubocurarine. In contrast to the force enhancing effects found with twitch and unfused tetanic stimulation, nifedipine caused a small but significant reduction in isometric force during maximal fused tetanic stimulation. It is concluded that the force potentiating effects of nifedipine on rat diaphragm are not due to fiber recruitment, enhancement of neuromuscular excitation, or altered inward trans-sarcolemmal calcium flux, but may result from a direct effect of the drug on the rate of activation of the contractile apparatus.  相似文献   
157.
Since the first discovery of deep-sea hydrothermal vents along the Galápagos Rift in 1977, numerous vent sites and endemic faunal assemblages have been found along mid-ocean ridges and back-arc basins at low to mid latitudes. These discoveries have suggested the existence of separate biogeographic provinces in the Atlantic and the North West Pacific, the existence of a province including the South West Pacific and Indian Ocean, and a separation of the North East Pacific, North East Pacific Rise, and South East Pacific Rise. The Southern Ocean is known to be a region of high deep-sea species diversity and centre of origin for the global deep-sea fauna. It has also been proposed as a gateway connecting hydrothermal vents in different oceans but is little explored because of extreme conditions. Since 2009 we have explored two segments of the East Scotia Ridge (ESR) in the Southern Ocean using a remotely operated vehicle. In each segment we located deep-sea hydrothermal vents hosting high-temperature black smokers up to 382.8°C and diffuse venting. The chemosynthetic ecosystems hosted by these vents are dominated by a new yeti crab (Kiwa n. sp.), stalked barnacles, limpets, peltospiroid gastropods, anemones, and a predatory sea star. Taxa abundant in vent ecosystems in other oceans, including polychaete worms (Siboglinidae), bathymodiolid mussels, and alvinocaridid shrimps, are absent from the ESR vents. These groups, except the Siboglinidae, possess planktotrophic larvae, rare in Antarctic marine invertebrates, suggesting that the environmental conditions of the Southern Ocean may act as a dispersal filter for vent taxa. Evidence from the distinctive fauna, the unique community structure, and multivariate analyses suggest that the Antarctic vent ecosystems represent a new vent biogeographic province. However, multivariate analyses of species present at the ESR and at other deep-sea hydrothermal vents globally indicate that vent biogeography is more complex than previously recognised.  相似文献   
158.
The innate recognition of fungi by leukocytes is mediated by pattern recognition receptors (PRR), such as Dectin-1, and is thought to occur at the cell surface triggering intracellular signalling cascades which lead to the induction of protective host responses. In the lung, this recognition is aided by surfactant which also serves to maintain the balance between inflammation and pulmonary function, although the underlying mechanisms are unknown. Here we have explored pulmonary innate recognition of a variety of fungal particles, including zymosan, Candida albicans and Aspergillus fumigatus, and demonstrate that opsonisation with surfactant components can limit inflammation by reducing host-cell fungal interactions. However, we found that this opsonisation does not contribute directly to innate fungal recognition and that this process is mediated through non-opsonic PRRs, including Dectin-1. Moreover, we found that pulmonary inflammatory responses to resting Aspergillus conidia were initiated by these PRRs in acidified phagolysosomes, following the uptake of fungal particles by leukocytes. Our data therefore provides crucial new insights into the mechanisms by which surfactant can maintain pulmonary function in the face of microbial challenge, and defines the phagolysosome as a novel intracellular compartment involved in the innate sensing of extracellular pathogens in the lung.  相似文献   
159.
Previous studies have demonstrated the feasibility of translocator protein (TSPO) imaging to visualize and quantify human breast adenocarcinoma (MDA-MB-231) cells in vivo using a TSPO-targeted near-infrared (NIR) probe (NIR-conPK11195). This study aimed to extend the use of the TSPO-targeted probe to a more biologically relevant and clinically important tumor microenvironment as well as to assess our ability to longitudinally detect the presence and progression of breast cancer cells in the brain. The in vivo biodistribution and accumulation of NIR-conPK11195 and free (unconjugated) NIR dye were quantitatively evaluated in intracranial MDA-MB-231-bearing mice and non-tumor-bearing control mice longitudinally once a week from two to five weeks post-inoculation. The in vivo time-activity curves illustrate distinct clearance profiles for NIR-conPK11195 and free NIR dye, resulting in preferential accumulation of the TSPO-targeted probe in the intracranial tumor bearing hemisphere (TBH) with significant tumor contrast over normal muscle tissue (p < 0.005 at five weeks; p < 0.01 at four weeks). In addition, the TSPO-labeled TBHs demonstrated significant contrast over the TBHs of mice injected with free NIR dye (p < 0.001 at four and five weeks) as well as over the TSPO-labeled non-tumor-bearing hemispheres (NTBHs) of control mice (p < 0.005 at four and five weeks). Overall, TSPO-targeted molecular imaging appears useful for visualizing and quantifying breast cancer xenografts propagated in the murine brain and may assist in preclinical detection, diagnosis and monitoring of metastatic disease as well as drug discovery. Furthermore, these results indicate it should be possible to perform TSPO-imaging of breast cancer cells in the brain using radiolabeled TSPO-targeted agents, particularly in light of the fact that [11C]-labeled TSPO probes such as [11C]-PK 11195 have been successfully used to image gliomas in the clinic.  相似文献   
160.
Life history parameters were determined for stranded and bycaught harbor porpoises (Phocoena phocoena) from Scottish (UK) waters (1992–2005). Fetal growth rate was 84.4 mm/mo and mean size at birth was 76.4 cm (range 65–88 cm). Males and females had a similar range of body lengths (65–170 cm and 66–173 cm, respectively), although asymptotic lengths were higher in females than males (approximately 158 cm and 147 cm, respectively). Nonpregnant females were significantly lighter, in relation to their length than males. Maximum estimated age was 20 yr for both sexes. Age at sexual maturity (ASM) was estimated as 4.35 yr in females and 5.00 yr in males. Conception occurred mainly in July and August although reproductively active males were recorded during April to July. Gestation lasted 10–11 mo, with calving mainly between May and July. Lactating females were recorded during June to November, while small calves with solid food in their stomachs were found mainly during February to May. Estimated pregnancy rate (0.34–0.40) is lower than recorded elsewhere, but is likely underestimated due to the prevalence of mature females of poor health status in the sample. Nevertheless, cetacean strandings can be an essential source of data on demographic parameters.  相似文献   
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