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1. As for some other spring‐feeding moths, adult flight of Epirrita autumnata (Lepidoptera: Geometridae) occurs in late autumn. Late‐season flight is a result of a prolonged pupal period. Potential evolutionary explanations for this phenological pattern are evaluated. 2. In a laboratory rearing, there was a weak correlation between pupation date and the time of adult emergence. A substantial genetic difference in pupal period was found between two geographic populations. Adaptive evolution of eclosion time can thus be expected. 3. Metabolic costs of a prolonged pupal period were found to be moderate but still of some ecological significance. Pupal mortality is likely to form the main cost of the prolonged pupal period. 4. Mortality rates of adults, exposed in the field, showed a declining temporal trend from late summer to normal eclosion time in autumn. Lower predation pressure on adults may constitute the decisive selective advantage of late‐season flight. It is suggested that ants, not birds, were the main predators responsible for the temporal trend. 5. Egg mortality was estimated to be low; it is thus unlikely that the late adult period is selected for to reduce the time during which eggs are exposed to predators. 6. In a laboratory experiment, oviposition success was maximal at the time of actual flight peak of E. autumnata, however penalties resulting from sub‐optimal timing of oviposition remained limited.  相似文献   
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DC‐UbP/UBTD2 is a ubiquitin (Ub) domain‐containing protein first identified from dendritic cells, and is implicated in ubiquitination pathway. The solution structure and backbone dynamics of the C‐terminal Ub‐like (UbL) domain were elucidated in our previous work. To further understand the biological function of DC‐UbP, we then solved the solution structure of the N‐terminal domain of DC‐UbP (DC‐UbP_N) and studied its Ub binding properties by NMR techniques. The results show that DC‐UbP_N holds a novel structural fold and acts as a Ub‐binding domain (UBD) but with low affinity. This implies that the DC‐UbP protein, composing of a combination of both UbL and UBD domains, might play an important role in regulating protein ubiquitination and delivery of ubiquitinated substrates in eukaryotic cells.  相似文献   
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A growing body of literature has shown that stem cells are very effective for the treatment of degenerative diseases in rodents but these exciting results have not translated to clinical practice. The difference results from the divergence in genetic, metabolic, and physiological phenotypes between rodents and humans. The high degree of similarity between non-human primates(NHPs) and humans provides the most accurate models for preclinical studies of stem cell therapy. Using a NHP model to understand the following key issues, which cannot be addressed in humans or rodents, will be helpful for extending stem cell applications in the basic science and the clinic. These issues include pluripotency of primate stem cells, the safety and efficiency of stem cell therapy, and transplantation procedures of stem cells suitable for clinical translation. Here we review studies of the above issues in NHPs and current challenges of stem cell applications in both basic science and clinical therapies. We propose that the use of NHP models, in particular combining the serial production and transplantation procedures of stem cells is the most useful for preclinical studies designed to overcome these challenges.  相似文献   
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We investigated the correlation between the beneficial effect of Lactobacillus acidophilus on gut microbiota composition, metabolic activities, and reducing cow's milk protein allergy. Mice sensitized with β‐lactoglobulin (β‐Lg) were treated with different doses of L. acidophilus KLDS 1.0738 for 4 weeks, starting 1 week before allergen induction. The results showed that intake of L. acidophilus significantly suppressed the hypersensitivity responses, together with increased fecal microbiota diversity and short‐chain fatty acids (SCFAs) concentration (including propionate, butyrate, isobutyrate, and isovalerate) when compared with the allergic group. Moreover, treatment with L. acidophilus induced the expression of SCFAs receptors, G‐protein–coupled receptors 41 (GPR41) and 43 (GPR43), in the spleen and colon of the allergic mice. Further analysis revealed that the GPR41 and GPR43 messenger RNA expression both positively correlated with the serum concentrations of transforming growth factor‐β and IFN‐γ (p < .05), but negatively with the serum concentrations of IL‐17, IL‐4, and IL‐6 in the L. acidophilus–treated group compared with the allergic group (p < .05). These results suggested that L. acidophilus protected against the development of allergic inflammation by improving the intestinal flora, as well as upregulating SCFAs and their receptors GPR41/43.  相似文献   
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Statistical mechanics provides the link between microscopic properties of many-particle systems and macroscopic properties such as pressure and temperature. Observations of similar “microscopic” quantities exist for the motion of zooplankton, as well as many species of other social animals. Herein, we propose to take average squared velocities as the definition of the “ecological temperature” of a population under different conditions on nutrients, light, oxygen and others. We test the usefulness of this definition on observations of the crustacean zooplankton Daphnia pulicaria. In one set of experiments, D. pulicaria is infested with the pathogen Vibrio cholerae, the causative agent of cholera. We find that infested D. pulicaria under light exposure have a significantly greater ecological temperature, which puts them at a greater risk of detection by visual predators. In a second set of experiments, we observe D. pulicaria in cold and warm water, and in darkness and under light exposure. Overall, our ecological temperature is a good discriminator of the crustacean’s swimming behavior.  相似文献   
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The rupture risk of unruptured intracranial aneurysms is known to be dependent on the size of the aneurysm. However, the association of morphological characteristics with ruptured aneurysms has not been established in a systematic and location specific manner for the most common aneurysm locations. We evaluated posterior communicating artery (PCoA) aneurysms for morphological parameters associated with aneurysm rupture in that location. CT angiograms were evaluated to generate 3-D models of the aneurysms and surrounding vasculature. Univariate and multivariate analyses were performed to evaluate morphological parameters including aneurysm volume, aspect ratio, size ratio, distance to ICA bifurcation, aneurysm angle, vessel angles, flow angles, and vessel-to-vessel angles. From 2005–2012, 148 PCoA aneurysms were treated in a single institution. Preoperative CTAs from 63 patients (40 ruptured, 23 unruptured) were available and analyzed. Multivariate logistic regression revealed that smaller volume (p = 0.011), larger aneurysm neck diameter (0.048), and shorter ICA bifurcation to aneurysm distance (p = 0.005) were the most strongly associated with aneurysm rupture after adjusting for all other clinical and morphological variables. Multivariate subgroup analysis for patients with visualized PCoA demonstrated that larger neck diameter (p = 0.018) and shorter ICA bifurcation to aneurysm distance (p = 0.011) were significantly associated with rupture. Intracerebral hemorrhage was associated with smaller volume, larger maximum height, and smaller aneurysm angle, in addition to lateral projection, male sex, and lack of hypertension. We found that shorter ICA bifurcation to aneurysm distance is significantly associated with PCoA aneurysm rupture. This is a new physically intuitive parameter that can be measured easily and therefore be readily applied in clinical practice to aid in the evaluation of patients with PCoA aneurysms.  相似文献   
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This paper defines a collection of Drosophila deletion mutations (deficiencies) that can be systematically screened for embryonic phenotypes, orphan receptor ligands, and genes affecting protein localization. It reports the results of deficiency screens we have conducted that have revealed new axon guidance phenotypes in the central nervous system and neuromuscular system and permitted a quantitative assessment of the number of potential genes involved in regulating guidance of specific motor axon branches. Deficiency “kits” that cover the genome with a minimum number of lines have been established to facilitate gene mapping. These kits cannot be systematically analyzed for phenotypes, however, since embryos homozygous for many deficiencies in these kits fail to develop due to the loss of key gene products encoded within the deficiency. To create new kits that can be screened for phenotype, we have examined the development of the nervous system in embryos homozygous for more than 700 distinct deficiency mutations. A kit of ∼400 deficiency lines for which homozygotes have a recognizable nervous system and intact body walls encompasses >80% of the genome. Here we show examples of screens of this kit for orphan receptor ligands and neuronal antigen expression. It can also be used to find genes involved in expression, patterning, and subcellular localization of any protein that can be visualized by antibody staining. A subset kit of 233 deficiency lines, for which homozygotes develop relatively normally to late stage 16, covers ∼50% of the genome. We have screened it for axon guidance phenotypes, and we present examples of new phenotypes we have identified. The subset kit can be used to screen for phenotypes affecting all embryonic organs. In the future, these deficiency kits will allow Drosophila researchers to rapidly and efficiently execute genome-wide anatomical screens that require examination of individual embryos at high magnification.  相似文献   
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