Sensory neurons located in dorsal root ganglia (DRG) convey sensory information from peripheral tissue to the brain. After peripheral nerve injury, sensory neurons switch to a regenerative state to ...enable axon regeneration and functional recovery. This process is not cell autonomous and requires glial and immune cells. Macrophages in the DRG (DRGMacs) accumulate in response to nerve injury, but their origin and function remain unclear. Here, we mapped the fate and response of DRGMacs to nerve injury using macrophage depletion, fate-mapping, and single-cell transcriptomics. We identified three subtypes of DRGMacs after nerve injury in addition to a small population of circulating bone-marrow-derived precursors. Self-renewing macrophages, which proliferate from local resident macrophages, represent the largest population of DRGMacs. The other two subtypes include microglia-like cells and macrophage-like satellite glial cells (SGCs) (Imoonglia). We show that self-renewing DRGMacs contribute to promote axon regeneration. Using single-cell transcriptomics data and CellChat to simulate intercellular communication, we reveal that macrophages express the neuroprotective and glioprotective ligand prosaposin and communicate with SGCs via the prosaposin receptor GPR37L1. These data highlight that DRGMacs have the capacity to self-renew, similarly to microglia in the Central nervous system (CNS) and contribute to promote axon regeneration. These data also reveal the heterogeneity of DRGMacs and their potential neuro- and glioprotective roles, which may inform future therapeutic approaches to treat nerve injury.
Shape is an objective characteristic of an object. A boundary separates a physical object from its surroundings. It defines the shape and regulates energy flux into and from an object. Visual ...perception of a definite shape (geometry) of physical objects is an abstraction. While the perceived geometry at an object's sharp interface (macro) creates a Euclidian illusion of actual shape, the notion of diffuse interfaces (micro) allows an understanding of the realistic form of objects. Here, we formulate a dimensionless geometric entropy of plant leaves (SL) by a 2-D description of a phase-field function. We applied this method to 112 tropical plant leaf images. SL was estimated from the leaf perimeter (P) and leaf area (A). It correlates positively with a fractal dimensional measure of leaf complexity, viz., segmental fractal complexity. Leaves with a higher P: A ratio have higher SL and possess complex morphology. The univariate cluster analysis of SL reveals the taxonomic relationship among the leaf shapes at the genus level. An increase in SL of plant leaves could be an evolutionary strategy. The results of morphological complexity presented in this paper will trigger discussion on the causal links between leaf adaptive stability/efficiency and complexity. We present SL as a derived plant trait to describe plant leaf complexity and adaptive stability. Integrating SL into other leaf physiological measures will help to understand the dynamics of energy flow between plants and their environment.
Vertebrate Delta/Notch signaling involves multiple ligands, receptors and transcription factors. Delta endocytosis - a critical event for Notch activation - is however essentially controlled by the ...E3 Ubiquitin ligase Mindbomb1 (Mib1). Mib1 inactivation is therefore often used to inhibit Notch signaling. However, recent findings indicate that Mib1 function extends beyond the Notch pathway. We report a novel Notch-independent role of Mib1 in zebrafish gastrulation.
null mutants and morphants display impaired Convergence Extension (CE) movements. Comparison of different
mutants and functional rescue experiments indicate that Mib1 controls CE independently of Notch. Mib1-dependent CE defects can be rescued using the Planar Cell Polarity (PCP) downstream mediator RhoA, or enhanced through knock-down of the PCP ligand Wnt5b. Mib1 regulates CE through its RING Finger domains that have been implicated in substrate ubiquitination, suggesting that Mib1 may control PCP protein trafficking. Accordingly, we show that Mib1 controls the endocytosis of the PCP component Ryk and that Ryk internalization is required for CE. Numerous morphogenetic processes involve both Notch and PCP signaling. Our observation that during zebrafish gastrulation Mib1 exerts a Notch-independent control of PCP-dependent CE movements suggest that Mib1 loss-of-function phenotypes should be cautiously interpreted depending on the biological context.
Anti-regenerative scarring obstructs spinal cord repair in mammals and presents a major hurdle for regenerative medicine. In contrast, adult zebrafish possess specialized glial cells that ...spontaneously repair spinal cord injuries by forming a pro-regenerative bridge across the severed tissue. To identify the mechanisms that regulate differential regenerative capacity between mammals and zebrafish, we first defined the molecular identity of zebrafish bridging glia and then performed cross-species comparisons with mammalian glia. Our transcriptomics show that pro-regenerative zebrafish glia activate an epithelial-to-mesenchymal transition (EMT) gene program and that EMT gene expression is a major factor distinguishing mammalian and zebrafish glia. Functionally, we found that localized niches of glial progenitors undergo EMT after spinal cord injury in zebrafish and, using large-scale CRISPR-Cas9 mutagenesis, we identified the gene regulatory network that activates EMT and drives functional regeneration. Thus, non-regenerative mammalian glia lack an essential EMT-driving gene regulatory network that reprograms pro-regenerative zebrafish glia after injury.
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•Bulk and single cell transcriptomes of regenerative zebrafish glia were generated•Pathways that distinguish regenerative zebrafish glia from mammalian glia were defined•An injury-induced EMT transcriptional module localizes to zebrafish glial progenitors•EMT transcription factors direct mesenchymal fate and regenerative bridging in zebrafish
Shaw et al. defined the molecular identity of regenerative zebrafish glia and performed cross-species comparisons with mammalian glia. They found that EMT localizes to zebrafish glial progenitors and distinguishes mammalian and zebrafish glia. They uncovered evidence that an EMT transcriptional module reprograms glial progenitors and promotes spinal cord repair in zebrafish.
Migration and migrant movement are a global scenario, in which one of the main drivers, which facilitates migrant movement, is the search for better living conditions. One of the most vulnerable ...communities in this regard is migrant workers, especially in the developing world, who conduct cross-country migration. Labour migration is a significant national phenomenon in India in which the workers migrate across the states, which were facilitated by the interstate movement. The recent outbreak of pandemic COVID-19 poses the greatest challenge to the migrant workers who face the challenge of displacement due to the restriction of movement and public perception. One of the significant actors facilitating public discourse is the media, which explores the migrant scenario through framing. This article analyzes how the Indian newspaper portrays the plight of the migrant workers in Kerala through media framing using qualitative case analysis. The study reveals that the media frames portray the plight of the migrant workers during the pandemic situation, and the result could be helpful for policy developers on immigrant’s integration.
War, domestic violence, and economic instability in a country force its residents to flee their homeland and their place of birth to a different part of the world to save their lives, and around 70.8 ...million people have been displaced across the world (UNHCR, 2019). It is also a fundamental fact that women and children who have fled in this manner have been subject to various forms of violence and torture during their journey. Refugees are increasingly interested in emigrating to the United States of America, given the political and economic importance of the nation. Nevertheless, the United States has a strict legal system in place to prevent uncontrolled immigration, and hence the refugees face a variety of problems in order to travel to it. Refugees, particularly those travelling tens of thousands of kilometres are from Central American countries, Africa, Iran, and Syria, have arrived in many towns along the US-Mexico border. Increasing numbers of refugees force governments of the receiving countries to provide accommodation, food, and other facilities, which causes an inevitable financial crisis in the receiving regions. In such cases, the non-governmental organizations (NGOs) play a significant role in helping refugees with various types of assistance, and it is important to analyze the human rights activities of NGOs. NGOs have been a lobbyist in influencing legislators through a variety of political consultations and creating laws that protect refugees. It is crucial that NGOs can influence the Government level and various types of Cabinet Meetings, to study the issues of refugees and provide different kinds of possible support and assistance through their advocacy activities. The influence of the new media technologies in this twenty-first century has increased the opportunity to understand the lives of different people from different parts of the world and conduct various socio-political debates on global issues, such as the refugee crisis. Therefore, we need to evaluate the role of the social media of NGOs as a lobbyist in advocacy on addressing the refugee crisis. The article aims to identify the role of NGOs in addressing the migrant crisis and upholding the sanctuary policy in Florida that facilitates migrant integration. Research methods include a qualitative interview with the Florida Immigrant Coalition (FIC) and analyzing its social media discourse. The anti-sanctuary bill passed by the Florida state legislature were analysed; the analysis shows that the advocacy for the refugee crisis by NGOs using social media platforms increases civic participation. Such activism has a significant role in influencing policy framework on combating the crisis of refugee integration.
Based on a systematic and comprehensive review of literature on emigration, we identify potential non-economic push factors that might drive Lithuanian citizens to emigrate. Based on a random sample ...nationwide survey conducted in spring 2019 with Lithuanian citizens living in Lithuania, two categories have emerged as most critical non-economic drivers to lead to higher intention to emigrate: quality of working life and confidence in the future. Further research can add necessary nuance to understanding these factors while also experimenting with possible policy and project interventions that can reduce intent to emigrate and/or encourage return migration. This research is implemented under the project "The importance of non-economic factors to the emigration of the Lithuanian population", funded by the Research Council of Lithuania under the Programme "Improvement of researchers' qualification by implementing world-class R&D projects" (Agreement No. 09.3.3-LMT-K-712-01-170).
Migracija ir migrantų judėjimas yra pasaulinė tendencija, kurią įtakoja keletas veiksnių. Vienas iš jų, palengvinančių migrantų judėjimą, yra geresnių gyvenimo sąlygų ieškojimas. Viena iš labiausiai ...pažeidžiamų bendruomenių šiuo atžvilgiu yra migrantai, ypač besivystančiame pasaulyje, vykdantys migraciją iš vienos šalies į kitą. Darbo jėgos migracija yra reikšmingas nacionalinis reiškinys Indijoje, kai darbuotojai migruoja po valstijas, o tai palengvino tarpvalstybinis judėjimas. Neseniai kilęs pandemijos COVID-19 protrūkis kelia didžiausią iššūkį darbuotojams migrantams, kurie susiduria su perkėlimo problema dėl judėjimo ir visuomenės suvokimo ribojimo. Vienas iš svarbiausių dalyvių, palengvinančių viešąjį diskursą, yra žiniasklaida, kuri rėmėsi migrantų scenarijaus formavimu. Šiame straipsnyje analizuojama, kaip Indijos laikraštis vaizduoja Keralos darbuotojų migrantų sunkumus per žiniasklaidos rėminimą naudojabt kokybinę atvejų analizę. Tyrimas atskleidžia, kad žiniasklaidos rėmuose vaizduojama migruojančių darbuotojų padėtis pandemijos metu ir rezultatas gali būti naudingas imigrantų integracijos politikos kūrėjams.
Refugee Crisis and the Role of NGO Lobbying Muraleedharan, Vishnu; Andrew Bryer, Thomas
Viešoji politika ir administravimas,
05/2020, Letnik:
19, Številka:
1
Journal Article
Recenzirano
Migration is a significant human phenomenon in which the people were moving across the globe in search of better living conditions. However, due to the violent political scenario between nations ...forced the displacement of millions of people for survival and currently, around 70.8 million people have been displaced across the world (UNHCR, 2019). It requires attention that even though there are various organisation’s to support migrants, NGO’s play a pivotal role in protecting humanitarian aspects of the migrants and their integration. About the NGO mechanisms, the significant measures are the lobbying and the mediatised political communication for effective policy changes. Therefore, it is significant to identify how NGO’s influence on political communication and policy decision making using social media platforms and lobbying mechanism in the state of Florida in the United States. The article aims to identify the role of NGO on addressing the migrant crisis and upholding of sanctuary policy in Florida which facilitates migrant integration. Research methods include a qualitative interview with the Florida Immigrant Coalition and their social media discourse. The finding could be useful for effective immigrant integration and the significant policy measures needed for facilitating migrant integration.
•Plant leaves are considered as natural fractals.•Self-similar patterns in plant leaves are absent over the complete range of scales.•Traditional box-counting fractal analysis is area dependent and ...fails to capture the lacunarity.•The study makes plant scientists aware of the uncertainties in plant leaves' traditional box-counting fractal analysis.
Fractal-based measures have widespread applications in the characterization of complex biological structures. Box-counting is one of the most widely used methods of fractal analysis. However, the utility of traditional box-counting fractal analysis in complexity studies is limited. We discuss the shortfalls of traditional fractal dimension (D) approaches in leaf complexity studies. Mature and healthy flat leaves of 61 plant species were collected from Trivandrum, Kerala, India. Digital images of these leaves were analyzed using the ImageJ software. No significant variations in D were seen in the results that could differentiate the leaf forms. We present the limitations and biases affecting accurate D analysis. Fractal properties of plant leaves are restricted over a limited scale, causing the failure of the linear regression-based D estimates. Arbitrary grid placement and miscounting the boxes of a specific size to cover the leaves are also subject to quantization errors. Since traditional fractal analysis depends on the bulk and boundary of the leaves, some D errors result from the potential bias of this area dependency. The traditional box-counting analysis also fails to capture the lacunarity observed in leaf images. Hence an accurate estimation of D is challenging using conventional methods. Considering the broad utility of fractal methods, plant researchers must be sensitized about the uncertainties in traditional box-counting approaches in complexity studies.
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