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《生物化学与生物物理学报:癌评论》2023,1878(2):188863
This review is an overview of the current knowledge regarding circulating tumour cells (CTCs), which are potentially the most lethal type of cancer cell, and may be a key component of the metastatic cascade. The clinical utility of CTCs (the "Good"), includes their diagnostic, prognostic, and therapeutic potential. Conversely, their complex biology (the "Bad"), including the existence of CD45+/EpCAM+ CTCs, adds insult to injury regarding their isolation and identification, which in turn hampers their clinical translation. CTCs are capable of forming microemboli composed of both non-discrete phenotypic populations such as mesenchymal CTCs and homotypic and heterotypic clusters which are poised to interact with other cells in the circulation, including immune cells and platelets, which may increase their malignant potential. These microemboli (the "Ugly") represent a prognostically important CTC subset, however, phenotypic EMT/MET gradients bring additional complexities to an already challenging situation. 相似文献
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Matthew L. Brien Jeffrey W. Lang Grahame J. Webb Colin Stevenson Keith A. Christian 《PloS one》2013,8(12)
We examined agonistic behaviour in seven species of hatchling and juvenile crocodilians held in small groups (N = 4) under similar laboratory conditions. Agonistic interactions occurred in all seven species, typically involved two individuals, were short in duration (5–15 seconds), and occurred between 1600–2200 h in open water. The nature and extent of agonistic interactions, the behaviours displayed, and the level of conspecific tolerance varied among species. Discrete postures, non-contact and contact movements are described. Three of these were species-specific: push downs by C. johnstoni; inflated tail sweeping by C. novaeguineae; and, side head striking combined with tail wagging by C. porosus. The two long-snouted species (C. johnstoni and G. gangeticus) avoided contact involving the head and often raised the head up out of the way during agonistic interactions. Several behaviours not associated with aggression are also described, including snout rubbing, raising the head up high while at rest, and the use of vocalizations. The two most aggressive species (C. porosus, C. novaeguineae) appeared to form dominance hierarchies, whereas the less aggressive species did not. Interspecific differences in agonistic behaviour may reflect evolutionary divergence associated with morphology, ecology, general life history and responses to interspecific conflict in areas where multiple species have co-existed. Understanding species-specific traits in agonistic behaviour and social tolerance has implications for the controlled raising of different species of hatchlings for conservation, management or production purposes. 相似文献
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Interleukin‐6 (IL‐6) is a pleiotropic cytokine with complex roles in inflammation and metabolic disease. While typically regarded as a pro‐inflammatory cytokine, multiple studies in the last 20 years have generated conflicting data on the role of IL‐6 in inflammation and metabolism. In a recent study in Nature Immunology, Brüning and collaborators demonstrate that IL‐6 signaling in myeloid cells attenuates obesity‐induced inflammation and insulin resistance by promoting macrophage alternative activation (Mauer et al, 2014 ). This study unveils a new and surprising anti‐inflammatory action of IL‐6 and further highlights the complex actions of this cytokine. 相似文献
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The Good,the Bad,and the Ugly: in search of gold standards for assessing functional genetic screen quality
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Variable screen quality, off‐target effects, and unclear false discovery rates often hamper large‐scale functional genomic screens in mammalian cells. Hart et al (2014) introduce gold standard reference sets of essential and non‐essential genes, aiming at standardizing the analysis of genome‐wide screens. This work provides a framework to compare both the quality and analysis methods of functional genetic screens. 相似文献
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C. A. Maltin M. I. Delday S. M. Hay F. G. Smith G. E. Lobley P. J. Reeds 《Bioscience reports》1987,7(2):143-149
The dietary administration of clenbuterol to young male rats has been shown to produce a muscle specific hypertrophic growth response. This paper demonstrates that the combined effect of drug treatment and hypertrophic stimulus induced by tenotomy produced an additive effect on muscle growth. This effect was demonstrated in terms of both muscle composition (protein and RNA) and fibre size. 相似文献
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Several studies investigating macroevolutionary skull shape variation in fossil reptiles were published recently, often using skull reconstructions taken from the scientific literature. However, this approach could be potentially problematic, because skull reconstructions might differ notably due to incompleteness and/or deformation of the material. Furthermore, the influence of intraspecific variation has usually not been explored in these studies. Both points could influence the results of morphometric analyses by affecting the relative position of species to each other within the morphospace. The aim of the current study is to investigate the variation in morphometric data between skull reconstructions based on the same specimen, and to compare the results to shape variation occurring in skull reconstructions based on different specimens of the same species (intraspecific variation) and skulls of closely related species (intraspecific variation). Based on the current results, shape variation of different skull reconstructions based on the same specimen seems to have generally little influence on the results of a geometric morphometric analysis, although it cannot be excluded that some erroneous reconstructions of poorly preserved specimens might cause problems occasionally. In contrast, for different specimens of the same species the variation is generally higher than between different reconstructions based on the same specimen. For closely related species, at least with similar ecological preferences in respect to the dietary spectrum, the degree of interspecific variation can overlap with that of intraspecific variation, most probably due to similar biomechanical constraints. 相似文献
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Gabor Szalai Yi Xu Roberto Romero Tinnakorn Chaiworapongsa Zhonghui Xu Po Jen Chiang Hyunyoung Ahn Birgitta Sundell Olesya Plazyo Yang Jiang Mary Olive Bing Wang Suzanne M. Jacques Faisal Qureshi Adi L. Tarca Offer Erez Zhong Dong Zoltan Papp Sonia S. Hassan Edgar Hernandez-Andrade Nandor Gabor Than 《PloS one》2014,9(11)
Objective
Soluble fms-like tyrosine kinase (sFlt)-1-e15a, a primate-specific sFlt-1-isoform most abundant in the human placenta in preeclampsia, can induce preeclampsia in mice. This study compared the effects of full-length human (h)sFlt-1-e15a with those of truncated mouse (m)sFlt-1(1-3) used in previous preeclampsia studies on pregnancy outcome and clinical symptoms in preeclampsia.Methods
Mice were injected with adenoviruses or fiber-mutant adenoviruses overexpressing hsFlt-1-e15a, msFlt-1(1-3) or control GFP under the CMV or CYP19A1 promoters on gestational day 8 (GD8) and GD11. Placentas and pups were delivered by cesarean section, and dams were monitored postpartum. Blood pressure was telemetrically recorded. Urine samples were collected with cystocentesis and examined for albumin/creatinine ratios. Tissue specimens were evaluated for transgene as well as endogenous mFlt-1 and msFlt-1-i13 expression. H&E-, Jones- and PAS-stained kidney sections were histopathologically examined. Placental GFP expression and aortic ring assays were investigated with confocal microscopy.Results
Mean arterial blood pressure (MAP) was elevated before delivery in hsFlt-1-e15a-treated mice compared to controls (GD18: ΔMAP = 7.8 mmHg, p = 0.009), while ΔMAP was 12.8 mmHg (GD18, p = 0.005) in msFlt-1(1-3)-treated mice. Urine albumin/creatinine ratio was higher in hsFlt-1-e15a-treated mice than in controls (GD18, p = 0.04; PPD8, p = 0.03), and msFlt-1(1-3)-treated mice had marked proteinuria postpartum (PPD8, p = 4×10−5). Focal glomerular changes were detected in hsFlt-1-e15a and msFlt-1(1-3)-treated mice. Aortic ring microvessel outgrowth was decreased in hsFlt-1-e15a (p = 0.007) and msFlt-1(1-3)-treated (p = 0.02) mice. Full-length msFlt-1-i13 expression was unique for the placenta. In hsFlt-1-e15a-treated mice, the number of pups (p = 0.046), total weight of living pups (p = 0.04) and maternal weights (p = 0.04) were higher than in controls. These differences were not observed in truncated msFlt-1(1-3)-treated mice.Conclusions
Truncated msFlt-1(1-3) simulated the preeclampsia-promoting effects of full-length hsFlt-1. MsFlt-1(1-3) had strong effect on maternal endothelium but not on placentas and embryos. In contrast, hsFlt-1-e15a induced preeclampsia-like symptoms; however, it also increased litter size. In accord with the predominant placental expression of hsFlt-1-e15a and msFlt-1-i13, full-length sFlt-1 may have a role in the regulation of embryonic development. These observations point to the difference in the biological effects of full-length and truncated sFlt-1 and the changes in the effect of full-length sFlt-1 during pregnancy, and may have important implications in the management of preeclampsia. 相似文献11.
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Woodring E. Wright Mieczyslaw A. Piatyszek William E. Rainey William Byrd Jerry W. Shay 《Genesis (New York, N.Y. : 2000)》1996,18(2):173-179
Telomerase is a ribonucleoprotein that synthesizes telomere repeats onto chromosome ends and is involved in maintaining telomere length in germline tissues and in immortal and cancer cells. In the present study, the temporal regulation of expression of telomerase activity was examined in human germline and somatic tissues and cells during development. Telomerase activity was detected in fetal, newborn, and adult testes and ovaries, but not in mature spermatozoa or oocytes. Blastocysts expressed high levels of telomerase activity as did most human somatic tissues at 16–20 weeks of development with the exception of human brain tissue. This activity could no longer be detected in the somatic tissues examined from the neonatal period onward. Neither placenta nor cultured fetal amniocytes contained detectable telomerase activity. Fetal tissues explanted into primary cell culture showed a dramatic decline in telomerase activity which became undetectable after the first passage in vitro. Elucidation of the regulatory pathways involved in the repression of telomerase activity during development may lead to the ability to manipulate telomerase levels and explore the consequences both for cellular aging and for the survival of cancer cells. © 1996 Wiley-Liss, Inc. 相似文献
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Developmental disorders originate in infancy or early childhood, are associated with presumed or observed organic abnormalities, and have serious long-term physical and/or psychological sequelae. Of particular interest here are two such disorders, mental retardation and autism. Purported causes range from genetics, early prenatal and/or postnatal exposure to toxins (including heavy metals), and recently, vaccinations. Single factors have often been claimed to be the cause of a developmental disorder, without regard to possible exacerbating or alleviating roles of other factors, including socioeconomic status. Unfortunately, professional and popular literature on both claimed causes and effective treatments has often been characterized by research and theorizing that is seriously flawed (bad science) or actively misrepresented (pseudoscience). The present paper critically reviews selected research on a few controversial issues concerning developmental disorders, particular mental retardation and autism, and emphasizes the role of low socioeconomic status. 相似文献
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B. B. Cael 《PloS one》2015,10(11)
For phytoplankton and other microbes, nutrient receptors are often the passages through which viruses invade. This presents a bottom-up vs. top-down, co-limitation scenario; how do these would-be-hosts balance minimizing viral susceptibility with maximizing uptake of limiting nutrient(s)? This question has been addressed in the biological literature on evolutionary timescales for populations, but a shorter timescale, mechanistic perspective is lacking, and marine viral literature suggests the strong influence of additional factors, e.g. host size; while the literature on both nutrient uptake and host-virus interactions is expansive, their intersection, of ubiquitous relevance to marine environments, is understudied. I present a simple, mechanistic model from first principles to analyze the effect of this co-limitation scenario on individual growth, which suggests that in environments with high risk of viral invasion or spatial/temporal heterogeneity, an individual host’s growth rate may be optimized with respect to receptor coverage, producing top-down selective pressure on short timescales. The model has general applicability, is suggestive of hypotheses for empirical exploration, and can be extended to theoretical studies of more complex behaviors and systems. 相似文献
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Mahmood Mamdani 《American anthropologist》2002,104(3):766-775
The link between Islam and terrorism became a central media concern following September 11, resulting in new rounds of "culture talk. This talk has turned religious experience into a political category, differentiating 'good Muslims" from "bad Muslims, rather than terrorists from civilians. The implication is undisguised: Whether in Afghanistan, Palestine, or Pakistan, Islam must be quarantined and the devil must be exorcized from it by a civil war between good Muslims and bad Muslims. This article suggests that we lift the quarantine and turn the cultural theory of politics on its head. Beyond the simple but radical suggestion that if there are good Muslims and bad Muslims, there must also be good Westerners and bad Westerners, I question the very tendency to read Islamist politics as an effect of Islamic civilization—whether good or bad—and Western power as an effect of Western civilization. Both those politics and that power are born of an encounter, and neither can be understood outside of the history of that encounter. Cultural explanations of political outcomes tend to avoid history and issues. Thinking of individuals from "traditional" cultures in authentic and original terms, culture talk dehistoricizes the construction of political identities. This article places the terror of September 11 in a historical and political context. Rather than a residue of a premodern culture in modern politics, terrorism is best understood as a modern construction. Even when it harnesses one or another aspect of tradition and culture, the result is a modern ensemble at the service of a modern project. [Keywords: Muslims, culture talk, Islamist politics, political identities, terrorism] 相似文献
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Tibor Bukovinszky Antonie M. Verschoor Nico R. Helmsing T. Martijn Bezemer Elisabeth S. Bakker Matthijs Vos Lisette N. de Senerpont Domis 《PloS one》2012,7(9)
Effects of food quality and quantity on consumers are neither independent nor interchangeable. Although consumer growth and reproduction show strong variation in relation to both food quality and quantity, the effects of food quality or food quantity have usually been studied in isolation. In two experiments, we studied the growth and reproduction in three filter-feeding freshwater zooplankton species, i.e. Daphnia galeata x hyalina, D. pulicaria and D. magna, on their algal food (Scenedesmus obliquus), varying in carbon to phosphorus (C∶P) ratios and quantities (concentrations). In the first experiment, we found a strong positive effect of the phosphorus content of food on growth of Daphnia, both in their early and late juvenile development. Variation in the relationship between the P-content of animals and their growth rate reflected interspecific differences in nutrient requirements. Although growth rates typically decreased as development neared maturation, this did not affect these species-specific couplings between growth rate and Daphnia P-content. In the second experiment, we examined the effects of food quality on Daphnia growth at different levels of food quantity. With the same decrease in P-content of food, species with higher estimated P-content at zero growth showed a larger increase in threshold food concentrations (i.e. food concentration sufficient to meet metabolic requirements but not growth). These results suggest that physiological processes such as maintenance and growth may in combination explain effects of food quality and quantity on consumers. Our study shows that differences in response to variation in food quality and quantity exist between species. As a consequence, species-specific effects of food quality on consumer growth will also determine how species deal with varying food levels, which has implications for resource-consumer interactions. 相似文献
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E. V. Shlyakhto L. A. Bokeria M. G. Rybakova E. N. Semernin G. V. Selivanova T. D. Vlasova K. B. Borisov V. N. Parfenov A. Ya. Goodkova 《Cell and Tissue Biology》2007,1(6):582-588
For a comparative analysis of cytomorphological characteristics of hypertrophied interventricular septum (IVS), both patients different ages with severe courses of obstructive hypertrophic cardiomyopathy (OHCMP) were examined, including children, and patients with essential arterial hypertension (EAH). The course of OHCMP in children as compared with adults was found to be characterized by considerable IVS hypertrophy that was accompanied by an acceleration of cardiomyocyte polyploidization. The mean ploidy level of cardiomyocytes in children with OHCMP was higher than in adult patients. The mean ploidy level of nuclei, the number of prolipherative cell nuclear antigen (PCNA)-positive nuclei, and the number of polyploid cardiomyocyte nuclei in adult patients with OHCMP were significantly higher statistically than in patients with EAH. The PCNA-positive labels in stromal cells were revealed only in patients with OHCMP. The obtained data indicate an important role of cardiomyocyte polyploidy and of activation of the proliferating cell nuclear antigen in development of myocardial hypertrophy in patients with OHCMP. 相似文献