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261.
Due to the high heterogeneity of lung adenocarcinoma (LUAD), molecular subtype based on gene expression profiles is of great significance for diagnosis and prognosis prediction in patients with LUAD. Invasion-related genes were obtained from the CancerSEA database, and LUAD expression profiles were downloaded from The Cancer Genome Atlas. The ConsensusClusterPlus was used to obtain molecular subtypes based on invasion-related genes. The limma software package was used to identify differentially expressed genes (DEGs). A multi-gene risk model was constructed by Lasso-Cox analysis. A nomogram was also constructed based on risk scores and meaningful clinical features. 3 subtypes (C1, C2 and C3) based on the expression of 97 invasion-related genes were obtained. C3 had the worst prognosis. A total of 669 DEGs were identified among the subtypes. Pathway enrichment analysis results showed that the DEGs were mainly enriched in the cell cycle, DNA replication, the p53 signalling pathway and other tumour-related pathways. A 5-gene signature (KRT6A, MELTF, IRX5, MS4A1 and CRTAC1) was identified by using Lasso-Cox analysis. The training, validation and external independent cohorts proved that the model was robust and had better prediction ability than other lung cancer models. The gene expression results showed that the expression levels of MS4A1 and KRT6A in tumour tissues were higher than in normal tissues, while CRTAC1 expression in tumour tissues was lower than in normal tissues. The 5-gene signature prognostic stratification system based on invasion-related genes could be used to assess prognostic risk in patients with LUAD.  相似文献   
262.
Acral melanoma is a rare melanoma subtype with distinct epidemiological, clinical and genetic features. To determine if acral melanoma cell lines are representative of this melanoma subtype, six lines were analysed by whole-exome sequencing and array comparative genomic hybridisation. We demonstrate that the cell lines display a mutation rate that is comparable to that of published primary and metastatic acral melanomas and observe a mutational signature suggestive of UV-induced mutagenesis in two of the cell lines. Mutations were identified in oncogenes and tumour suppressors previously linked to melanoma including BRAF, NRAS, KIT, PTEN and TP53, in cancer genes not previously linked to melanoma and in genes linked to DNA repair such as BRCA1 and BRCA2. Our findings provide strong circumstantial evidence to suggest that acral melanoma cell lines and acral tumours share genetic features in common and that these cells are therefore valuable tools to investigate the biology of this aggressive melanoma subtype. Data are available at: http://rock.icr.ac.uk/collaborations/Furney_et_al_2012/.  相似文献   
263.
Individualistic voices are important for establishing personalized relationships among individuals. In young animals, individual vocal identity is affected by permanent changes of the acoustics due to the growth of their vocal apparatus. Different acoustic variables change uncoordinatedly, so vocal individuality should be repeatedly upgraded along development. We compared classifying accuracy of individuals and sexes by nasal calls in fast-growing goitred gazelles Gazella subgutturosa at two ontogenetic stages, juvenile (3-6 weeks of age) and adolescent (23-26 weeks of age). Juvenile "spring" nasal calls and adolescent "fall" nasal calls were examined in the same 35 calves (18 males, 17 females), wild-born in May and then hand-raised. Discriminate function analysis based on four formants, fundamental frequency, duration and three power quartiles, revealed an equally high potential of spring and fall calls to encode sex. The individuality was very high in both ages but significantly higher in fall calls. Classifying calls to individuals was based on the same three acoustic variables (fundamental frequency and third and fourth formants) in both ages, although their actual values changed uncoordinatedly from spring to fall in most subjects. Our results suggest updating acoustic individuality in nasal calls of adolescent goitred gazelles accordingly to the newly emerged acoustic variation.  相似文献   
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高新宇  关悦  陈曦  刘娟  金英兰  王京华 《生物磁学》2012,(28):5555-5557
目的:探讨68例多发性骨髓瘤MM患者的临床首发症状,实验室相关检查特点。方法:回顾分析我院2002年1月-2012年3月期间68例MM患者临床表现及实验室相关资料。结果:68例MM患者中临床表现具有多样性,细胞形态学检查中骨髓瘤细胞比例大于20%的占76%,骨髓瘤细胞比例小于20%的占24%,骨髓中成熟红细胞呈缗钱状排列者占78%,血清蛋白电泳中53例患者出现M蛋白,免疫球蛋白IgG增高15例,IgA增高11例,轻链型4例,X线检查结果48例提示骨质有异常改变。结论:临床表现和实验室检查对明确诊断MM及早期治疗都有很重要的意义。  相似文献   
266.
Human speech evidently conveys an adaptive advantage, given its apparently rapid dissemination through the ancient world and global use today. As such, speech must be capable of altering human biology in a positive way, possibly through those neuroendocrine mechanisms responsible for strengthening the social bonds between individuals. Indeed, speech between trusted individuals is capable of reducing levels of salivary cortisol, often considered a biomarker of stress, and increasing levels of urinary oxytocin, a hormone involved in the formation and maintenance of positive relationships. It is not clear, however, whether it is the uniquely human grammar, syntax, content and/or choice of words that causes these physiological changes, or whether the prosodic elements of speech, which are present in the vocal cues of many other species, are responsible. In order to tease apart these elements of human communication, we examined the hormonal responses of female children who instant messaged their mothers after undergoing a stressor. We discovered that unlike children interacting with their mothers in person or over the phone, girls who instant messaged did not release oxytocin; instead, these participants showed levels of salivary cortisol as high as control subjects who did not interact with their parents at all. We conclude that the comforting sound of a familiar voice is responsible for the hormonal differences observed and, hence, that similar differences may be seen in other species using vocal cues to communicate.  相似文献   
267.
The vocal repertoire of the mandrill (Mandrillus sphinx), a forest living baboon, is described, and their vocal communication analyzed quantitatively. Although the vocal repertoire of mandrills corresponds well to that of savanna living baboons,Papio, some characteristics differed, such as the development of long-distance calls and differentiation of vocalizations between age-sex classes. Vocal communication within a group was closely related to changes in the spatial distribution of group members, and the two most common vocalizations, crowing and 2PG, appear to function as contact calls. Based on the wide dispersion of food trees, a group of mandrills divided into several feeding groups (subgroups). The two types of contact call were given in different and in some senses complementary contexts, and helped to facilitate and maintain group integration. According to their acoustic structure, these calls are long distance calls. Influenced by the high-level of attenuation of vocalization on the forest floor, the mandrill has developed them as contact calls, instead of using the contact “grunt,” which is common to the savanna living baboons. Comparing the patterns of vocal exchanges of mandrills with those of gelada and hamadryas baboons which have a multi-levelled society, the social structure of the mandrill is discussed. From the analysis of the spatial distribution of vocal emission, a number of clusters of vocalizations were obtained. These clusters correspond to subgroups. The frequent female-female and female-male vocal exchange between subgroups of mandrills suggest that the relationships between subgroups are less closed than between the one-male units of gelada and hamadryas baboons. Furthermore some of these clusters include more than two vocalizing adult males, while in other clusters there are no vocalizing adult males. Thus, the social structure of mandrills is suggested to be multi-male rather than a multilevelled type. The absence of contact calls specific for short distance and the functional replacement of the grunting of all group members by persistent emission of a loud call (2PG) by usually just one adult male suggests that the social structure of mandrills is not exactly equivalent to that of the multimale troop of savanna living baboons. Usually the use of 2PG is monopolized by one adult male travelling in the rear part of the group. Such monopolization of 2PG emission and the pattern of 2PG-2PG or 2PG-roar exchanges by adult males in some cases indicate the existence of strong dominance relationships among adult males, and especially the existence of a leader male within a multi-male group of mandrills.  相似文献   
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Pancreatic cancer is a malignancy of the digestive system characterized by poor prognosis. A number of prognostic messenger RNA (mRNA) signatures have been identified by using the high-throughput expression profiles. MicroRNAs (miRNA) play a critical role in regulating multiple cellular functions. However, no such integrated analysis of miRNAs and mRNAs for studying the prognostic mechanisms of pancreatic cancer has been reported. In this study, we first identified prognostic mRNAs and miRNAs based on The Cancer Genome Atlas datasets, and then performed an enrichment analysis to explore the underlying biological mechanisms involved in pancreatic cancer prognosis at the mRNA level. Furthermore, we performed an integrated analysis of mRNAs and miRNAs to identify prognostic subpathways, which were closely associated with pancreatic cancer genes and tumor hallmarks and involved in hypoxia, oxidative phosphyorylation and xenobiotic metabolisms. Meanwhile, we performed a random walk algorithm based on global network, prognostic mRNAs and miRNAs, and identified top risk mRNAs as the prognostic signature. Finally, an independent testing set was used to confirm the predictive power of the top mRNA signature, and most of these genes involved were known oncogenes. In conclusion, we performed a series of integrated analyses by comprehensively exploring pancreatic cancer prognosis and systematically optimized the prognostic signature for clinical use.  相似文献   
270.
Bacillus subtilis inorganic pyrophosphatase is the first member of a newly identified Family II of PPases. To examine the role of a signature sequence found near the C-terminus, two truncated variants and a series of site-specific mutants were produced. A truncation of 17 residues (17AATR) but also single alanine substitutions, R295A and K296A, produced inactive enzyme. Removal of 5 nonconserved terminal residues (5AATR) markedly affected enzyme stability. Replacing S294 with A, T, C, or V decreased activity, the latter two mutations showing the greatest effect. Substitutions V299I and V300I had no or minor effects, whereas V300W and V299G/V300W significantly reduced activity. The sizes of truncated proteins and the full-length PPase were indistinguishable by gel-filtration. We conclude that the C-terminus has no role in multimerization, while both its conserved and nonconserved regions are essential for full enzyme activity. The signature sequence is required for both the conformation and composition of the active site.  相似文献   
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