scholarly journals Sessile bacterium unlocks ability of surface motility through mutualistic interspecies interaction

2020 ◽  
Author(s):  
Miaoxiao Wang ◽  
Shuang Geng ◽  
Bing Hu ◽  
Yong Nie ◽  
Xiao-Lei Wu
Keyword(s):  
Critical Role ◽  
Large Body ◽  
Selective Advantage ◽  
Food Sources ◽  
Natural Environments ◽  
Interspecies Interaction ◽  
Interaction Mode ◽  
Mutualistic Relationship ◽  
Surface Motility ◽  
Motile Bacteria

AbstractIn addition to their common planktonic lifestyle, bacteria frequently live in surface-associated habitats. Surface motility is essential for exploring these habitats for food sources. However, many bacteria are found on surfaces, even though they lack features required for migrating along surfaces. How these canonical non-motile bacteria adapt to the environmental fluctuations on surfaces remains unknown. Recently, several cases of interspecies interaction were reported that induce surface motility of non-motile bacteria either by using ‘hitchhiking’ strategies or through ‘social spreading’ mechanisms. Here, we report a previously unknown mechanism for interaction-dependent surface motility of the canonical non-motile bacterium, Dietzia sp. DQ12-45-1b, which is induced by interaction with a dimorphic prosthecate bacterium, Glycocaulis alkaliphilus 6B-8T. Dietzia cells exhibits “sliding”-like motility in an area where the strain Glycocaulis cells was pre-colonized with a sufficient density. Furthermore, we show that biosurfactants play a critical role in inducing the surface motility of Dietzia cells. Our analysis also demonstrates that Dietzia degrade n-alkanes and provide Glycocaulis with the resulting metabolites for survival, which in turn enabled directional migration of Dietzia towards nutrients in the environment. Such interaction-dependent migration was also found between Dietzia and Glycocaulis strains isolated from other habitats, suggesting that this mutualistic relationship ubiquitously occurs in natural environments. In conclusion, we propose a novel model for such a ‘win-win’ strategy, whereby non-motile bacteria pay metabolites to dimorphic prosthecate bacteria in return for migrating to reach environments otherwise inaccessible. We propose that this mechanism represents a common strategy for canonically non-motile bacteria living on a surface.ImportanceCell motility provides a selective advantage for bacteria searching for nutrients. While a large body of evidence exists for how motile bacteria migrate on surface by virtue of different ways of motility, fewer studies concerned about how canonical non-motile bacteria adapted to those surface-associated habitats. Recent reports have proposed that interactions with other bacteria trigger the movement of those sessile bacteria. However, these interactions are limited to ‘hitchhiking’ or ‘social spreading’ modes. Here, we characterized a previously unknown interaction mode between Dietzia and Glycocaulis.This interaction differs from previously described modes, thus advance our limited understanding of how sessile bacteria move on surfaces. We propose that this interaction mode represents a ‘win-win’ strategy for both strains, and this mode might be widely distributed across diverse environments. These novel insights should greatly assist in understanding the mechanisms responsible for the cellular interplay between microbes in complex microbiomes.

scholarly journals Beyond DNA Repair: DNA-PKcs in Tumor Metastasis, Metabolism and Immunity

Cancers ◽  
2020 ◽  
Vol 12 (11) ◽  
pp. 3389
Author(s):  
Haitang Yang ◽  
Feng Yao ◽  
Thomas M. Marti ◽  
Ralph A. Schmid ◽  
Ren-Wang Peng
Keyword(s):  
Tumor Metastasis ◽  
Immune Escape ◽  
Critical Role ◽  
Large Body ◽  
Tumor Development ◽  
Dna Double Strand Breaks ◽  
End Joining ◽  
Strand Breaks ◽  
Dependent Protein ◽  
Non Homologous End Joining

The DNA-dependent protein kinase catalytic subunit (DNA-PKcs) is a key component of the DNA-PK complex that has a well-characterized function in the non-homologous end-joining repair of DNA double-strand breaks. Since its identification, a large body of evidence has demonstrated that DNA-PKcs is frequently overexpressed in cancer, plays a critical role in tumor development and progression, and is associated with poor prognosis of cancer patients. Intriguingly, recent studies have suggested novel functions beyond the canonical role of DNA-PKcs, which has transformed the paradigm of DNA-PKcs in tumorigenesis and has reinvigorated the interest to target DNA-PKcs for cancer treatment. In this review, we update recent advances in DNA-PKcs, in particular the emerging roles in tumor metastasis, metabolic dysregulation, and immune escape. We further discuss the possible molecular basis that underpins the pleiotropism of DNA-PKcs in cancer. Finally, we outline the biomarkers that may predict the therapeutic response to DNA-PKcs inhibitor therapy. Understanding the functional repertoire of DNA-PKcs will provide mechanistic insights of DNA-PKcs in malignancy and, more importantly, may revolutionize the design and utility of DNA-PKcs-based precision cancer therapy.

Who are the Asset-Poor in China: A Comprehensive Description and Policy Implications

2019 ◽  
Vol 48 (4) ◽  
pp. 765-787
Author(s):  
YUANYUAN YANG ◽  
JUN-HONG CHEN ◽  
MINCHAO JIN
Keyword(s):  
Critical Role ◽  
Large Body ◽  
Well Being ◽  
Developed Countries ◽  
Urban China ◽  
Policy Implications ◽  
Income Poverty ◽  
Chinese Government ◽  
Household Asset ◽  
Asset Poverty

AbstractThere is a large body of literature asserting that household asset holdings play a critical role in prospects of economic and social well-being. This study examines asset-poverty rates in China using the 2013 survey data from the Chinese Household Income Project (CHIP). The results indicate that asset-poverty rates in urban China were lower than those of developed countries, whereas rural and migrant households experienced more serious asset poverty than their counterparts in urban China. In addition, the asset-poverty rates were at least twice the income-poverty rates in China according to the different poverty lines used in the study. Several demographic characteristics were found associated with asset poverty. To assist the Chinese government in reaching its goal of eradicating absolute poverty by 2020 through targeted poverty alleviation, this study suggests including assets in the description and alleviation of poverty.

scholarly journals A Review of the Evidence for and against a Role for Mast Cells in Cutaneous Scarring and Fibrosis

2020 ◽  
Vol 21 (24) ◽  
pp. 9673
Author(s):  
Traci A. Wilgus ◽  
Sara Ud-Din ◽  
Ardeshir Bayat
Keyword(s):  
Mast Cell ◽  
Mast Cells ◽  
Cell Activation ◽  
Social Issues ◽  
Critical Role ◽  
Large Body ◽  
Repair Process ◽  
Scar Tissue ◽  
Mast Cell Activation

Scars are generated in mature skin as a result of the normal repair process, but the replacement of normal tissue with scar tissue can lead to biomechanical and functional deficiencies in the skin as well as psychological and social issues for patients that negatively affect quality of life. Abnormal scars, such as hypertrophic scars and keloids, and cutaneous fibrosis that develops in diseases such as systemic sclerosis and graft-versus-host disease can be even more challenging for patients. There is a large body of literature suggesting that inflammation promotes the deposition of scar tissue by fibroblasts. Mast cells represent one inflammatory cell type in particular that has been implicated in skin scarring and fibrosis. Most published studies in this area support a pro-fibrotic role for mast cells in the skin, as many mast cell-derived mediators stimulate fibroblast activity and studies generally indicate higher numbers of mast cells and/or mast cell activation in scars and fibrotic skin. However, some studies in mast cell-deficient mice have suggested that these cells may not play a critical role in cutaneous scarring/fibrosis. Here, we will review the data for and against mast cells as key regulators of skin fibrosis and discuss scientific gaps in the field.

Collecting Ethnographic Video Data for Policy Research

2019 ◽  
Vol 63 (3) ◽  
pp. 387-403 ◽  
Author(s):  
Joanne W. Golann ◽  
Zitsi Mirakhur ◽  
Thomas J. Espenshade
Keyword(s):  
Critical Role ◽  
Policy Research ◽  
Extended Period ◽  
Holistic Approach ◽  
Ethnographic Study ◽  
Video Data ◽  
Natural Environments ◽  
Home Video ◽  
Parent Child Interactions ◽  
Role Of Parents

Despite growing recognition of the critical role of parents in children’s early development, parenting education programs and interventions typically have had limited impacts on children’s outcomes. To design programs and policies that are more responsive to families’ needs and constraints, policymakers need a better understanding of the lived experiences of families. In this article, we argue that qualitative video-ethnographic approaches offer an innovative and useful supplement to policy researchers’ usual tool kit. Taking a holistic approach to parent–child interactions and filming families in their natural environments over an extended period provides policy researchers with new data to inform future parenting initiatives. To assist researchers interested in undertaking a video-ethnographic study, we discuss our experiences with the New Jersey Families Study, a 2-week, in-home video study of 21 families with a 2- to 4-year-old child. This is the first time anyone has attempted an in-home naturalistic observation of this breadth, intensity, or duration. We highlight the potential of this method for policy relevance along with its associated challenges.

Seasonal Changes in Sugar and Amino Acid Preference in Red Wood Ants of The Formica rufa Group

Sociobiology ◽  
2020 ◽  
Vol 67 (2) ◽  
pp. 144
Author(s):  
Natalia E.L. Madsen ◽  
Joachim Offenberg
Keyword(s):  
Amino Acid ◽  
Seasonal Changes ◽  
Food Sources ◽  
Individual Species ◽  
Sugar Solution ◽  
Formica Rufa ◽  
Red Wood Ants ◽  
Wood Ants ◽  
Formica Rufa Group ◽  
Mutualistic Relationship

Red wood ants of the Formica rufa group are important ecosystem engineers throughout the Northern Hemisphere with potential to be commercially produced and used as predatory agents in biological control programs. However, in order to do that, their mutualistic relationship with aphids needs to be disrupted. This may be achieved by developing artificial sugar-based solutions with a composition that makes them more attractive than aphid honeydew. The present field study investigated Formica rufa’s preference for several sugar and amino acid sources, as well as potential seasonal changes in these preferences. Red wood ants consistently preferred sucrose to monosaccharides and were most attracted to solutions containing an amino acid source, albeit seasonal differences were observed with regard to which amino acid sources were most preferred. Recruitment to offered sugar solutions was highest during July, when colony requirements were high, and during October, when alternative food sources were scarce. Since ant preference for sugar solution constituents seems to be species-specific and show seasonal dynamics, artificial food aimed at disrupting ant-aphid mutualisms should be tailored to individual species and seasons.

A computational approach to prefrontal cortex, cognitive control and schizophrenia: recent developments and current challenges

1996 ◽  
Vol 351 (1346) ◽  
pp. 1515-1527 ◽  
Keyword(s):  
Prefrontal Cortex ◽  
Reaction Time ◽  
Cognitive Control ◽  
Critical Role ◽  
Large Body ◽  
Computational Approach ◽  
Similar Reaction ◽  
Current Form ◽  
Stage Of Development ◽  
Recent Developments

In this chapter we consider the mechanisms involved in cognitive control - from both a computational and a neurobiological perspective — and how these might be impaired in schizophrenia. By ‘control’, we mean the ability of the cognitive system to flexibly adapt its behaviour to the demands of particular tasks, favouring the processing of task-relevant information over other sources of competing information, and mediating task-relevant behaviour over habitual, or otherwise prepotent responses. There is a large body of evidence to suggest that the prefrontal cortex (PFC) plays a critical role in cognitive control. In previous work, we have used a computational framework to understand and develop explicit models of this function of PFC, and its impairment in schizophrenia. This work has lead to the hypothesis that PFC houses a mechanism for representing and maintaining context information. We have demonstrated that this mechanism can account for the behavioural inhibition and active memory functions commonly ascribed to PFC, and for human performance in simple attention, language and memory tasks that draw upon these functions for cognitive control. Furthermore, we have used our models to simulate detailed patterns of cognitive deficit observed in schizophrenia, an illness associated with marked disturbances in cognitive control, and well established deficits of PFC. Here, we review results of recent empirical studies that test predictions made by our models regarding schizophrenic performance in tasks designed specifically to probe the processing of context. These results showed selective schizophrenic deficits in tasks conditions that placed the greatest demands on memory and inhibition, both of which we have argued rely on the processing of context. Furthermore, we observed predicted patterns of deterioration in first episode vs multi-episode patients. We also discuss recent developments in our computational work, that have led to refinements of the models that allow us to simulate more detailed aspects of task performance, such as reaction time data and manipulations of task parameters such as interstimulus delay. These refined models make several provocative new predictions, including conditions in which schizophrenics and control subjects are expected to show similar reaction time performance, and we provide preliminary data in support of these predictions. These successes notwithstanding, our theory of PFC function and its impairment in schizophrenia is still in an early stage of development. We conclude by presenting some of the challenges to the theory in its current form, and new directions that we have begun to take to meet these challenges. In particular, we focus on refinements concerning the mechanisms underlying active maintenance of representations within PFC, and the characteristics of these representations that allow them to support the flexibility of cognitive control exhibited by normal human behaviour. Taken in toto , we believe that this work illustrates the value of a computational approach for understanding the mechanisms responsible for cognitive control, at both the neural and psychological levels, and the specific manner in which they break down in schizophrenia.

scholarly journals Using causality and correlation analysis to decipher microbial interactions in activated sludge

2021 ◽  
Author(s):  
Weiwei Cai ◽  
Xiangyu Han ◽  
Hong Yao
Keyword(s):  
Time Series ◽  
Activated Sludge ◽  
Network Theory ◽  
Time Series Data ◽  
Microbial Interactions ◽  
Series Data ◽  
Natural Environments ◽  
Cell Aggregate ◽  
Causality Analysis ◽  
Mutualistic Relationship

Network theory is widely used to understand microbial interactions in activated sludge and numerous other artificial and natural environments. However, when using correlation-based methods, it is not possible to identify the directionality of interactions within microbiota. Based on the classic Granger test of sequencing-based time-series data, a new Microbial Causal Correlation Network (MCCN) was constructed with distributed ecological interaction on the directed, associated links. As a result of applying MCCN to a time series of activated sludge data, we found that the hub species OTU56, classified as belonging the genus Nitrospira, was responsible for completing nitrification in activated sludge, and mainly interacted with Proteobacteria and Bacteroidetes in the form of amensal and commensal relationships, respectively. Phylogenetic tree suggested a mutualistic relationship between Nitrospira and denitrifiers. Zoogloea displayed the highest ncf value within the classified OTUs of the MCCN, indicating that it could be a foundation for activated sludge through forming the characteristic cell aggregate matrices into which other organisms embed during floc formation. Overall, the introduction of causality analysis greatly expands the ability of a network to shed a light on understanding the interactions between members of a microbial community.

scholarly journals Do young domestic pigs (Sus scrofa domestica) rely on object-specific cues in a simultaneous discrimination task?

2014 ◽  
Author(s):  
Christian Nawroth ◽  
Eberhard von Borell
Keyword(s):  
Discrimination Task ◽  
Instrumental Learning ◽  
Simultaneous Discrimination ◽  
Food Sources ◽  
Natural Environments ◽  
Learning Mechanisms ◽  
Learning Abilities ◽  
Domestic Pigs ◽  
Food Container ◽  
Young Pigs

Finding and relocating food sources is not only crucial for individuals in changing natural environments - it is also of importance in domestic animals under husbandry conditions, for instance to reduce stress when transferring animals into new housing conditions. This study makes a first attempt by investigating young pigs´ use of conflicting spatial and feature cues in a simultaneous discrimination task. In a training phase, subjects (n = 9) first learned to approach a food container with distinct spatial and feature cues. In a subsequent test phase, spatial and feature cues were brought into conflict. Results show that young pigs significantly preferred to approach the spatial position rather than the feature cue of a food container – at least for the visual domain - while inter-individual differences in choice behaviour suggest that animals recognized the changed context. However, the actual test setup did not exclude alternatives to the use of spatial cues, e.g. instrumental learning. The results may contribute to a better understanding of learning mechanisms in domestic pigs and could be used to improve husbandry designs, reduce stress levels after transfer and may prove to be helpful in designing further test paradigms investigating discriminative learning abilities in the domestic pig.

scholarly journals ANK3 Gene Polymorphism Rs10994336 Influences Executive Functions by Modulating Methylation in Patients With Bipolar Disorder

2021 ◽  
Vol 15 ◽  
Author(s):  
Lili Tang ◽  
Juan Liu ◽  
Yue Zhu ◽  
Jia Duan ◽  
Yifan Chen ◽  
...  
Keyword(s):  
Bipolar Disorder ◽  
Executive Functions ◽  
Epigenetic Modification ◽  
Association Studies ◽  
Critical Role ◽  
Large Body ◽  
Wisconsin Card Sorting Test ◽  
Genome Wide Association Studies ◽  
Card Sorting ◽  
Significant Difference

Background: A large body of evidence suggests that epigenetic modification including DNA methylation plays a critical role in BD's pathogenesis while the identification of methylation quantitative trait loci (meQTLs) shed light on the interpretation of the function of genetic variants in non-coding regions. The intronic single nucleotide polymorphism (SNP) rs10994336 within the ANK3 has emerged as one of the most replicated risk variants for bipolar disorder (BD) in genome-wide association studies. Whether rs10994336 functions as a meQTL to mediate the association between genotype and phenotype remains unclear.Method: A total of 154 patients with BD and 181 healthy controls (HC) were recruited. The genotypes of rs10994336 and methylation levels of CpG sites within ANK3 were tested. Executive functions were assessed using a computerized version of the Wisconsin Card Sorting Test (WCST).Results: Bipolar disorder patients with the risk-T allele of rs10994336 scored lower on tests of executive function compared to homozygous CC carriers, after controlling for age, gender, and education level. No significant difference was found in HC individuals. The risk-T allele is associated with a lower methylation level of CpG site cg02172182 in HC after multiple corrections and replicated in the BD group in the same direction. Further mediation analysis revealed that the cg02172182 methylation significantly mediated the association between the polymorphism rs10994336 and PE index of WCST in patients with BD.Conclusion: Our study suggests that BD-related genetic variant rs10994336 in ANK3 impacts executive functions by modulating ANK3 methylation, supporting the theory that methylation acts as a mediator between genotype and phenotype.

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