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61.
Melanoma is a disease associated with a very high mutation burden and thus the possibility of a diverse range of oncogenic mechanisms that allow it to evade therapeutic interventions and the immune system. Here, we describe the characterization of a panel of 102 cell lines from metastatic melanomas (the NZM lines), including using whole‐exome and RNA sequencing to analyse genetic variants and gene expression changes in a subset of this panel. Lines possessing all major melanoma genotypes were identified, and hierarchical clustering of gene expression profiles revealed four broad subgroups of cell lines. Immunogenotyping identified a range of HLA haplotypes as well as expression of neoantigens and cancer–testis antigens in the lines. Together, these characteristics make the NZM panel a valuable resource for cell‐based, immunological and xenograft studies to better understand the diversity of melanoma biology and the responses of melanoma to therapeutic interventions.  相似文献   
62.
C4 plants evolved from C3 plants through a series of complex evolutionary steps. On the basis of the evolution of key C4 enzyme genes, the evolution of C4 photosynthesis has been considered a story of gene/genome duplications and subsequent modifications of gene function. If whole-genome duplication has contributed to the evolution of C4 photosynthesis, other genes should have been duplicated together with these C4 genes. However, which genes were co-duplicated with C4 genes and whether they have also played a role in C4 evolution are largely unknown. In this study, we developed a simple method to characterize the historical profile of the paralogs of a gene by tracing back to the most recent common ancestor (MRCA) of the gene and its paralog(s) and then counting the number of paralogs at each MRCA. We clustered the genes into clusters with similar duplication profiles and inferred their functional enrichments. Applying our method to maize, a familiar C4 plant, we identified many genes that show similar duplication profiles with those of the key C4 enzyme genes and found that the functional preferences of the C4 gene clusters are not only similar to those identified by an experimental approach in a recent study but also highly consistent with the functions required for the C4 photosynthesis evolutionary model proposed by S.F. Sage. Some of these genes might have co-evolved with the key C4 enzyme genes to increase the strength of C4 photosynthesis. Moreover, our results suggested that most key C4 enzyme genes had different origins and have undergone a long evolutionary process before the emergence of C4 grasses (Andropogoneae), consistent with the conclusion proposed by previous authors.  相似文献   
63.
The phagocytic activity of neuroglial cells in adult feline degenerating optic nerve was investigated by immunocytochemistry at both light and electron microscopy levels. Degeneration was initiated by unilateral eye enucleation and the segment distal to the transection showing true Wallerian degeneration was examined. Following enucleation, twelve adult domestic cats were examined over a period of seven to 215 days. All cases showed slow clearance of myelin debris and absence of proliferating monocytes throughout the post-enucleation period. All phagocytic cells present were neuroglial cells, and many of these cells expressed oligodendroglial antigens. These findings demonstrate the persistence of an active population of oligodendrocytes that might play an additional functional role during Wallerian degeneration of feline optic nerve.  相似文献   
64.
Choristopsychidae, established by Martynov in 1937 with a single isolated forewing, is a little known extinct family in Mecoptera. Since then, no new members of this enigmatic family have been described. Based on 23 well-preserved specimens with complete body and wings from the Middle Jurassic of northeastern China, we report one new genus and three new species of Choristopsychidae, two new species of the genus Choristopsyche Martynov, 1937: Choristopsyche perfecta sp. n. and Choristopsyche asticta sp. n.; one new species of Paristopsyche gen. n.: Paristopsyche angelineae sp. n.; and re-describe Choristopsyche tenuinervis Martynov, 1937. In addition, we emend the diagnoses of Choristopsychidae and Choristopsyche. Analyzing the forewing length/width ratios of representative species in Mecoptera, we confirm that choristopsychids have the lowest ratio of forewing length/width, meaning broadest forewings. These findings, the first fossil choristopsychids with well-preserved body structure and the first record of Choristopsychidae in China, shed light on the morphology of these taxa and broaden their distribution from Tajikistan to China, while increasing the diversity of Mesozoic Mecoptera in China.  相似文献   
65.
Eucalyptus species are grown widely outside of their native ranges in plantations on all vegetated continents of the world. We predicted that such a plantation species would show high potential for acclimation of photosynthetic traits across a wide range of growth conditions, including elevated [CO2] and climate warming. To test this prediction, we planted temperate Eucalyptus globulus Labill. seedlings in climate‐controlled chambers in the field located >700 km closer to the equator than the nearest natural occurrence of this species. Trees were grown in a complete factorial combination of elevated CO2 concentration (eC; ambient [CO2] +240 ppm) and air warming treatments (eT; ambient +3 °C) for 15 months until they reached ca. 10 m height. There was little acclimation of photosynthetic capacity to eC and hence the CO2‐induced photosynthetic enhancement was large (ca. 50%) in this treatment during summer. The warming treatment significantly increased rates of both carboxylation capacity (Vcmax) and electron transport (Jmax) (measured at a common temperature of 25 °C) during winter, but decreased them significantly by 20–30% in summer. The photosynthetic CO2 compensation point in the absence of dark respiration (Γ*) was relatively less sensitive to temperature in this temperate eucalypt species than for warm‐season tobacco. The temperature optima for photosynthesis and Jmax significantly changed by about 6 °C between winter and summer, but without further adjustment from early to late summer. These results suggest that there is an upper limit for the photosynthetic capacity of E. globulus ssp. globulus outside its native range to acclimate to growth temperatures above 25 °C. Limitations to temperature acclimation of photosynthesis in summer may be one factor that defines climate zones where E. globulus plantation productivity can be sustained under anticipated global environmental change.  相似文献   
66.
67.
Since the first study of hypoxic response in plants with cDNA microarray in 2002, the number of hypoxia-responsive genes has grown to more than 2000. However, to date, only small numbers of hypoxia-responsive genes are known to confer hypoxic resistance. Most investigations in this area have focused on identifying which genes are responsive and then characterized how these genes are induced during hypoxia, but the roles of numerous genes in hypoxic response are still unknown. In our recent study, we demonstrated that a group of genes are induced by submergence to trigger plant immunity, which is a response to protect plants against a higher probability of pathogen infection during or after flooding. This work offered a brand new perspective, i.e., that hypoxia-responsive genes can be induced for reasons other than conferring hypoxic resistance. Possible reasons why these responses were triggered are discussed herein.  相似文献   
68.
In previous research, we found α-enolase to be inversely correlated with progression-free and overall survival in lung cancer patients and detected α-enolase on the surface of lung cancer cells. Based on these findings, we hypothesized that surface α-enolase has a significant role in cancer metastasis and tested this hypothesis in the current study. We found that α-enolase was co-immunoprecipitated with urokinase-type plasminogen activator, urokinase-type plasminogen activator receptor, and plasminogen in lung cancer cells and interacted with these proteins in a cell-free dot blotting assay, which can be interrupted by α-enolase-specific antibody. α-Enolase in lung cancer cells co-localized with these proteins and was present at the site of pericellular degradation of extracellular matrix components. Treatment with antibody against α-enolase in vitro suppressed cell-associated plasminogen and matrix metalloproteinase activation, collagen and gelatin degradation, and cell invasion. Examination of the effect of treatment with shRNA plasmids revealed that down regulation of α-enolase decreases extracellular matrix degradation by and the invasion capacity of lung cancer cells. Adoptive transfer of α-enolase-specific antibody to mice resulted in accumulation of antibody in subcutaneous tumor and inhibited the formation of tumor metastasis in lung and bone. This study demonstrated that surface α-enolase promotes extracellular matrix degradation and invasion of cancer cells and that targeting surface α-enolase is a promising approach to suppress tumor metastasis.  相似文献   
69.
Hydrophylita emporos n. sp. reared from eggs of Psolodesmus mandarinus mandarinus McLachlan (Zygoptera: Calopterygidae) in Taiwan is described. This is the first species of Hydrophylita to be described from the Old World, and the first record of phoresy in the genus. Adult females were observed aggregating at the base of the female damselfly’s abdomen. When the damselfly begins ovipositing, females move to the tip of the abdomen, enter the water and quickly locate eggs for parasitising. The article contains links to video footage of this process.  相似文献   
70.
Wu  Po-Ming  Lin  Chih-Hao  Lee  Hsueh-Te  Shih  Hsin-I  Huang  Chao-Ching  Tu  Yi-Fang 《Neurochemical research》2020,45(11):2712-2722
Neurochemical Research - Neonatal hypoxic–ischemic encephalopathy is the most common cause of neurological disability in infancy. Superimposed inflammation may further worsen neurological...  相似文献   
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