Chemical constituents from Baphia leptobotrys Harms (Fabaceae) and their chemophenetic significance

The chemical investigation of the CH₂Cl₂/MeOH (1:1) extract of the trunk bark and leaves of Baphia leptobotrys Harms (Fabaceae) led to the isolation of nineteen compounds (1–19). Their structures were elucidated based on the analysis of their NMR and MS data. Except for compounds 3–5, 14 and 15, all the isolated compounds are reported from the genus Baphia for the first time. Furthermore, compounds 8, 10, 16, 17 are isolated from the Fabaceae family for the first time. The crude extract and isolated compounds were screened in vitro for their antileishmanial activity against Leishmania donovani 1S (MHOM/SD/62/1S) promastigotes and cytotoxicity towards Raw 264.7 macrophage cells. The crude extract of B. leptobotrys exhibited moderate activity (IC₅₀ = 63.40 μg/mL). Amongst the tested compounds, ergosterol peroxide (9) and germanicol caffeoyl ester (8) exhibited good activity with IC₅₀ values of 9.43 and 10.24 μM, respectively and showed acceptable selectivity towards macrophage cells (SI > 3.85). The chemophenetic significance of these compounds is also discussed.     

Evolutionary expansion and functional divergence of sugar transporters in Saccharum (S. spontaneum and S. officinarum)

The sugar transporter (ST) family is considered to be the most important gene family for sugar accumulation, but limited information about the ST family in the important sugar-yielding crop Saccharum is available due to its complex genetic background. Here, 105 ST genes were identified and clustered into eight subfamilies in Saccharum spontaneum. Comparative genomics revealed that tandem duplication events contributed to ST gene expansions of two subfamilies, PLT and STP, in S. spontaneum, indicating an early evolutionary step towards high sugar content in Saccharum. The analyses of expression patterns were based on four large datasets with a total of 226 RNA sequencing samples from S. spontaneum and Saccharum officinarum. The results clearly demonstrated 50 ST genes had different spatiotemporal expression patterns in leaf tissues, 10 STs were specifically expressed in the stem, and 10 STs responded to the diurnal rhythm. Heterologous expression experiments in the defective yeast strain EBY.VW4000 indicated STP13, pGlcT2, VGT3, and TMT4 are the STs with most affinity for glucose/fructose and SUT1_T1 has the highest affinity to sucrose. Furthermore, metabolomics analysis suggested STP7 is a sugar starvation-induced gene and STP13 has a function in retrieving sugar in senescent tissues. PLT11, PLT11_T1, TMT3, and TMT4 contributed to breaking the limitations of the storage sink. SUT1, SUT1_T1, PLT11, TMT4, pGlcT2, and VGT3 responded for different functions in these two Saccharum species. This study demonstrated the evolutionary expansion and functional divergence of the ST gene family and will enable the further investigation of the molecular mechanism of sugar metabolism in Saccharum.     

High genetic diversity despite drastic bottleneck in a critically endangered,long‐lived seabird,the Mascarene Petrel Pseudobulweria aterrima

The Mascarene Petrel Pseudobulweria aterrima is a critically endangered seabird endemic to Reunion Island, with an extremely small population suffering several threats. Fifteen polymorphic microsatellite loci were isolated from this species to analyse genetic diversity, estimate contemporary effective population size, search for evidence of a population bottleneck and see whether results support the hypothesis that life history traits could preserve allelic diversity in small populations. Results from 22 individuals found grounded as a consequence of light pollution highlight a surprisingly high genetic diversity, an absence of inbreeding, a contemporary effective population size estimated at approximately 1211 individuals and a probable bottleneck around 10 000 generations ago. Additional studies on genetic diversity and structure from a larger number of samples are thus required to evaluate the evolutionary potential of this critically endangered species.     

肺结核合并下呼吸道感染患者CT影像特点及IL-23R水平表达的临床意义

摘要 目的：探讨肺结核合并下呼吸道感染患者CT影像特点及IL-23R水平表达的临床意义。方法：选取2015年1月-2018年8月于我院就诊的123例肺结核患者,将所选取的患者按是否合并下呼吸道感染分为单纯肺结核组73例和肺结核合并下呼吸道感染组50例。分析两组组患者临床表现、CT影像学图片、CT影像学表现、血清IL-23R的表达水平的差异。结果：单纯肺结核组患者出现14例低热、11例胸闷、17例消瘦、14例气短、18例痰中带血、14例颈部淋巴结肿大、23例咳嗽、21例胸痛。肺结核合并下呼吸道感染组患者出现16例低热、13例胸闷、21例消瘦、19例气短、20例痰中带血、15例颈部淋巴结肿大、26例咳嗽、23例胸痛,两组患者临床表现差异均无统计学意义（P＞0.05）。单纯肺结核组CT影像学图片显示可见结节影或包块影,呈明显分叶征、短毛刺征、空泡征并发肺不张、棘状突起,边缘较清晰,增强扫描后明显强化。肺结核合并下呼吸道感染组CT影像学图片显示有分叶、毛刺,同时肺内肿物周边存在晕征、血管聚集征、卫星灶征、胸膜凹陷等表现,此外伴纵膈及肺门淋巴结明显肿大,胸壁侵犯。肺结核合并下呼吸道感染组CT影像中毛刺状结节、胸膜凹陷、空洞、分叶征、肿块、条索影比例均高于单纯肺结核组,差异有统计学意义（P＜0.05）。肺结核合并下呼吸道感染组患者IL-23R水平明显高于单纯肺结核组,差异有统计学意义（P＜0.05）。结论：与单纯肺结核患者相比较,肺结核合并下呼吸道感染患者临床表现更为严重,CT影像学特点更为明显,患者血清中IL-23R表达水平明显升高,临床可通过CT影像学结合血清IL-23R检测,以提高肺结核合并下呼吸道感染患者的临床诊断。     

Life‐history traits related to diapause in univoltine and bivoltine populations of Ypthima multistriata (Lepidoptera: Satyridae) inhabiting similar latitudes

In most temperate insects, diapause strategies and voltinism generally exhibit latitudinal clines, supporting the concept that they represent adaptations to climate. In contrast, in the satyrine butterfly Ypthima multistriata Butler, local populations with different voltinism patterns are geographically intermingled, suggesting that life‐history traits related to diapause may differ even between geographically and phylogenetically close populations. In this study, we experimentally examined the critical photoperiod for diapause induction and the larval developmental period in two univoltine and two bivoltine populations of Y. multistriata, all of which inhabit virtually the same latitude (34.652–34.750°N). We found that the critical photoperiod for diapause induction was longer in the univoltine populations than in the bivoltine populations. Moreover, the larval period under the long day length treatment was different among populations in both sexes, although significant differences were also detected between populations with the same voltinism. These results indicate that in Y. multistriata, life‐history traits related to diapause can not be attributed merely to climatic conditions such as temperature or day length, which depend largely on latitude. Therefore, we suggest that biotic elements, such as leaf toughness, as well as abiotic elements should be taken into account in attempts to explain the enigmatic pattern of geographic variation in the diapause strategies of Y. multistriata.     

Early evolutionary differentiation of morphological variation in the mandible of South American caviomorph rodents (Rodentia, Caviomorpha)

Caviomorphs are a clade of South American rodents recorded at least since the early Oligocene (> 31.5 Ma) that exhibit ample eco-morphological variation. It has been proposed that phylogenetic structure is more important than ecological factors for understanding mandibular shape variation in this clade. This was interpreted as a result of the long-standing evolutionary history of caviomorphs and the early divergence of major lineages. In this work, we test this hypothesis through the analysis of morphological variation in the mandible of living and extinct species and compare this information with that obtained through comparative phylogenetic analyses. Our results support the hypothesis of early origin of mandibular variation; moreover, they suggest the conservation of early differentiated morphologies, which could indicate the existence of constrained evolutionary diversification.     

The evolution of species interactions across natural landscapes

Given the potential for rapid and microgeographical adaptation, ecologists increasingly are exploring evolutionary explanations for community patterns. Biotic selection can generate local adaptations that alter species interactions. Although some gene flow might be necessary to fuel local adaptation, higher gene flow can homogenise traits across regions and generate local maladaptation. Herein, I estimate the contributions of local biotic selection, gene flow and spatially autocorrelated biotic selection to among-population divergence in traits involved in species interactions across 75 studies. Local biotic selection explained 6.9% of inter-population trait divergence, an indirect estimate of restricted gene flow explained 0.1%, and spatially autocorrelated selection explained 9.3%. Together, biotic selection explained 16% of the variance in population trait means. Most biotic selection regimes were spatially autocorrelated. Hence, most populations receive gene flow from populations facing similar selection, which could allow for local adaptation despite moderate gene flow. Gene flow constrained adaptation in studies conducted at finer spatial scales as expected, but this effect was often confounded with spatially autocorrelated selection. Results indicate that traits involved in species interactions might often evolve across landscapes, especially when biotic selection is spatially autocorrelated. The frequent evolution of species interactions suggests that evolutionary processes might often influence community ecology.     

Does rapid evolution matter? Measuring the rate of contemporary evolution and its impacts on ecological dynamics

Rapid contemporary evolution due to natural selection is common in the wild, but it remains uncertain whether its effects are an essential component of community and ecosystem structure and function. Previously we showed how to partition change in a population, community or ecosystem property into contributions from environmental and trait change, when trait change is entirely caused by evolution (Hairston et al. 2005). However, when substantial non-heritable trait change occurs (e.g. due to phenotypic plasticity or change in population structure) that approach can mis-estimate both contributions. Here, we demonstrate how to disentangle ecological impacts of evolution vs. non-heritable trait change by combining our previous approach with the Price Equation. This yields a three-way partitioning into effects of evolution, non-heritable phenotypic change and environment. We extend the approach to cases where ecological consequences of trait change are mediated through interspecific interactions. We analyse empirical examples involving fish, birds and zooplankton, finding that the proportional contribution of rapid evolution varies widely (even among different ecological properties affected by the same trait), and that rapid evolution can be important when it acts to oppose and mitigate phenotypic effects of environmental change. Paradoxically, rapid evolution may be most important when it is least evident.     

Biology of the sauropod dinosaurs: the evolution of gigantism

The herbivorous sauropod dinosaurs of the Jurassic and Cretaceous periods were the largest terrestrial animals ever, surpassing the largest herbivorous mammals by an order of magnitude in body mass. Several evolutionary lineages among Sauropoda produced giants with body masses in excess of 50 metric tonnes by conservative estimates. With body mass increase driven by the selective advantages of large body size, animal lineages will increase in body size until they reach the limit determined by the interplay of bauplan, biology, and resource availability. There is no evidence, however, that resource availability and global physicochemical parameters were different enough in the Mesozoic to have led to sauropod gigantism. We review the biology of sauropod dinosaurs in detail and posit that sauropod gigantism was made possible by a specific combination of plesiomorphic characters (phylogenetic heritage) and evolutionary innovations at different levels which triggered a remarkable evolutionary cascade. Of these key innovations, the most important probably was the very long neck, the most conspicuous feature of the sauropod bauplan. Compared to other herbivores, the long neck allowed more efficient food uptake than in other large herbivores by covering a much larger feeding envelope and making food accessible that was out of the reach of other herbivores. Sauropods thus must have been able to take up more energy from their environment than other herbivores. The long neck, in turn, could only evolve because of the small head and the extensive pneumatization of the sauropod axial skeleton, lightening the neck. The small head was possible because food was ingested without mastication. Both mastication and a gastric mill would have limited food uptake rate. Scaling relationships between gastrointestinal tract size and basal metabolic rate (BMR) suggest that sauropods compensated for the lack of particle reduction with long retention times, even at high uptake rates. The extensive pneumatization of the axial skeleton resulted from the evolution of an avian‐style respiratory system, presumably at the base of Saurischia. An avian‐style respiratory system would also have lowered the cost of breathing, reduced specific gravity, and may have been important in removing excess body heat. Another crucial innovation inherited from basal dinosaurs was a high BMR. This is required for fueling the high growth rate necessary for a multi‐tonne animal to survive to reproductive maturity. The retention of the plesiomorphic oviparous mode of reproduction appears to have been critical as well, allowing much faster population recovery than in megaherbivore mammals. Sauropods produced numerous but small offspring each season while land mammals show a negative correlation of reproductive output to body size. This permitted lower population densities in sauropods than in megaherbivore mammals but larger individuals. Our work on sauropod dinosaurs thus informs us about evolutionary limits to body size in other groups of herbivorous terrestrial tetrapods. Ectothermic reptiles are strongly limited by their low BMR, remaining small. Mammals are limited by their extensive mastication and their vivipary, while ornithsichian dinosaurs were only limited by their extensive mastication, having greater average body sizes than mammals.     

了哥王叶的结构特征及生态意义

运用冷冻切片技术,用光学显微镜对了哥王(Wikstroemia indica(L.)C.A.Mey.)叶的解剖结构进行了观察研究.结果表明,了哥王叶表现出许多旱生、阳生形态,兼具有中生特点.叶表皮由一层排列紧密形状不规则的细胞组成,细胞外壁角质膜较厚;上下表皮均无毛;气孔类型为无规则型,仅分布在下表皮且下陷,气孔密度较...