Developmental aspects of morphological disparity dynamics: a simple analytical exploration

Paleobiology ◽  
2011 ◽  
Vol 37 (2) ◽  
pp. 237-251 ◽  
Author(s):  
Sylvain Gerber ◽  
Gunther J. Eble ◽  
Pascal Neige
Keyword(s):  
Developmental Changes ◽  
Potential Contribution ◽  
Adult Size ◽  
Morphological Disparity ◽  
Standard Curve ◽  
Evolutionary Changes ◽  
Developmental Dynamics ◽  
Developmental Scheme ◽  
Average Adult

We have devised a simple model for assessing the role of development in shaping the evolution of morphological disparity. Disparity of a clade at any given time is expressed in terms of the developmental dynamics that lead to the variety of adult morphotypes observed. We use assumed phenotypic manifestations of developmental processes, as they could be detected from allometric characterizations, to distinguish a few, nonexclusive types of evolutionary changes in ontogeny. On the basis of this formalization, we describe the diversification of hypothetical clades, using the standard curve of adult morphological disparity, the curve of juvenile disparity, and the curve of allometric disparity, the latter quantifying the diversification of clades in allometric space. Contrasts of these curves reflect the underlying developmental scheme that drives temporal changes in disparity. We then vary the parameters of the model to assess the expected signature of each metric under specific conditions: changes in the relative frequencies of the types of evolutionary developmental changes, changes in the transition magnitude attached to each of them, and effects of temporal variation in average adult size on disparity curves and patterns of morphospace occupation. Results emphasize the potential contribution of these proxies for developmental dynamics—juvenile morphological disparity, allometric disparity, and average adult size—in enriching the interpretation of standard disparity curves and the description of clade histories, with possible process-oriented inferences.

Comparing the differential filling of morphospace and allometric space through time: the morphological and developmental dynamics of Early Jurassic ammonoids

Paleobiology ◽  
2011 ◽  
Vol 37 (3) ◽  
pp. 369-382 ◽  
Author(s):  
Sylvain Gerber
Keyword(s):  
Evolutionary Dynamics ◽  
Morphological Evolution ◽  
Taxonomic Diversity ◽  
Early Jurassic ◽  
Adult Size ◽  
Morphological Disparity ◽  
History Of ◽  
Developmental Dynamics ◽  
Shell Geometry ◽  
Average Adult

The evolutionary history of shell geometry of Early Jurassic ammonoids during the Pliensbachian–Toarcian second-order mass extinction is explored at both adult and ontogenetic levels. The ontogenetic approach builds on the concept of allometric space to get insights into the developmental aspects of morphological evolution. Investigation of the deployment of taxa in adult morphospace and allometric space allows the appraisal of the temporal evolution of morphological and allometric disparities. Curves of taxonomic diversity, adult morphological disparity, allometric disparity, and average adult size are contrasted. Results show that during the Pliensbachian–Toarcian interval, ammonoids underwent two successive and drastic declines in taxonomic diversity. Patterns of morphospace and allometric space occupancy suggest nonselective extinction at both morphological and developmental levels. Another measure of allometric disparity suggests the occurrence of two heterochronic trends, a peramorphocline followed by a paedomorphocline, during the Toarcian. These trends are concomitant with changes in average adult size that compensate for the heterochronic effects and explain the striking stability of morphological disparity despite changes in diversity. The results also emphasize the existence of two contrasted evolutionary dynamics in Pliensbachian and Toarcian ammonoids. Methodologically, the allometric disparity approach appears to be a fruitful tool to analyze the rather understudied clade-wide ontogenetic aspects of morphological evolution. Combining multiple approaches to describe clade morphological dynamics leads to a better characterization and understanding of the diversity-disparities relationships and a better distinction of the potential processes driving these macroevolutionary patterns.

scholarly journals Dietary Modulation of Bacteriophages as an Additional Player in Inflammation and Cancer

Cancers ◽  
2021 ◽  
Vol 13 (9) ◽  
pp. 2036
Author(s):  
Luigi Marongiu ◽  
Markus Burkard ◽  
Sascha Venturelli ◽  
Heike Allgayer
Keyword(s):  
Structural Damage ◽  
Folk Medicine ◽  
Gastrointestinal Diseases ◽  
Potential Contribution ◽  
Anticancer Properties ◽  
Specific Phage ◽  
Microbial Network ◽  
Inflammatory Bowel ◽  
Species Specific

Natural compounds such as essential oils and tea have been used successfully in naturopathy and folk medicine for hundreds of years. Current research is unveiling the molecular role of their antibacterial, anti-inflammatory, and anticancer properties. Nevertheless, the effect of these compounds on bacteriophages is still poorly understood. The application of bacteriophages against bacteria has gained a particular interest in recent years due to, e.g., the constant rise of antimicrobial resistance to antibiotics, or an increasing awareness of different types of microbiota and their potential contribution to gastrointestinal diseases, including inflammatory and malignant conditions. Thus, a better knowledge of how dietary products can affect bacteriophages and, in turn, the whole gut microbiome can help maintain healthy homeostasis, reducing the risk of developing diseases such as diverse types of gastroenteritis, inflammatory bowel disease, or even cancer. The present review summarizes the effect of dietary compounds on the physiology of bacteriophages. In a majority of works, the substance class of polyphenols showed a particular activity against bacteriophages, and the primary mechanism of action involved structural damage of the capsid, inhibiting bacteriophage activity and infectivity. Some further dietary compounds such as caffeine, salt or oregano have been shown to induce or suppress prophages, whereas others, such as the natural sweeter stevia, promoted species-specific phage responses. A better understanding of how dietary compounds could selectively, and specifically, modulate the activity of individual phages opens the possibility to reorganize the microbial network as an additional strategy to support in the combat, or in prevention, of gastrointestinal diseases, including inflammation and cancer.

Overcoming counter-knowledge through telemedicine communication technologies

2017 ◽  
Vol 31 (7/8) ◽  
pp. 730-745 ◽  
Author(s):  
Jorge Cegarra-Sanchez ◽  
Juan-Gabriel Cegarra-Navarro ◽  
Anthony Wensley ◽  
Jose Diaz Manzano
Keyword(s):  
Learning Process ◽  
Design Methodology ◽  
Communication Technologies ◽  
Regional Hospital ◽  
Potential Contribution ◽  
Exploration And Exploitation ◽  
Negative Effects ◽  
Content Type

Purpose Knowledge acquired from sources of unverified information such as gossip, partial truths or lies, in this paper it is termed as “counter-knowledge.” The purpose of this paper is to explore this topic through an exploration of the links between a Hospital-in-the-Home Units (HHUs) learning process (LP), counter-knowledge, and the utilization of communication technologies. The following two questions are addressed: Does the reduction of counter-knowledge result in the utilization of communication technologies? Does the development of counter-knowledge hinder the LP? Design/methodology/approach This paper examines the relevance of communication technologies to the exploration and exploitation of knowledge for 252 patients of a (HHU) within a Spanish regional hospital. The data collected was analyzed using the PLS-Graph. Findings To HHU managers, this study offers a set of guidelines to assist in their gaining an understanding of the role of counter-knowledge in organizational LPs and the potential contribution of communication technologies. Our findings support the proposition that the negative effects of counter-knowledge can be mitigated by using communication technologies. Originality/value It is argued in this paper that counter-knowledge may play a variety of different roles in the implementation of LPs. Specifically, the assignment of communication technologies to homecare units has given them the means to filter counter-knowledge and prevent users from any possible problems caused by such counter-knowledge.

Abstract WMP31: Dedifferentiation of Smooth Muscle Cells and its Potential Contribution to Pathogenesis of Intracranial Aneurysms

Stroke ◽  
2020 ◽  
Vol 51 (Suppl_1) ◽  
Author(s):  
Mieko Oka ◽  
Nobuhiko Ohno ◽  
Takakazu Kawamata ◽  
Tomohiro Aoki
Keyword(s):  
Endothelial Cells ◽  
Smooth Muscle ◽  
Smooth Muscle Cells ◽  
Inflammatory Responses ◽  
Muscle Cells ◽  
Inflammatory Factors ◽  
Potential Contribution ◽  
Electron Microscopic

Introduction: Intracranial aneurysm (IA) affects 1 to 5 % in general public and becomes the primary cause of subarachnoid hemorrhage, the most severe form of stroke. However, currently, no drug therapy is available for IAs to prevent progression and rupture of lesions. Elucidation of mechanisms underlying the disease is thus mandatory. Considering the important role of vascular smooth muscle cells (SMCs) in the maintenance of stiffness of arterial walls and also in the pathogenesis of atherosclerosis via mediating inflammatory responses, we in the present study analyzed morphological or phenotypical changes of SMCs during the disease development in the lesions. Methods: We subjected rats to an IA model in which lesions are induced by increase of hemodynamic force loading on intracranial arterial bifurcations and performed histopathological analyses of induced lesions including the electron microscopic examination. We then immunostained specimens from induced lesions to explore factors responsible for dedifferentiation or migration of SMCs. In vitro study was also done to examine effect of some candidate factors on dedifferentiation or migration of cultured SMCs. Results: We first found the accumulation of SMCs underneath the endothelial cell layer mainly at the neck portion of the lesion. These cells was positive for the embryonic form of myosin heavy chain, a marker for the dedifferentiated SMCs, and the expression of pro-inflammatory factors like TNF-α. In immunostaining to explore the potential factor regulating the dedifferentiation of SMCs, we found that Platelet-derived growth factor-BB (PDGF-BB) was expressed in endothelial cells at the neck portion of IA walls. Consistently, recombinant PDGF-BB could promote the dedifferentiate of SMCs and chemo-attracted them in in vitro. Finally, in the stenosis model of the carotid artery, PDGF-BB expression was induced in endothelial cells in which high wall shear stress was loaded and the dedifferentiation of SMCs occurred there. Conclusions: The findings from the present study imply the role of dedifferentiated SMCs partially recruited by PDGF-BB from endothelial cells in the formation of inflammatory microenvironment at the neck portion of IA walls, leading to the progression of the disease.

scholarly journals An abundance of developmental anomalies and abnormalities in Pleistocene people

2018 ◽  
Vol 115 (47) ◽  
pp. 11941-11946 ◽  
Author(s):  
Erik Trinkaus
Keyword(s):  
Fossil Record ◽  
Elevated Level ◽  
Developmental Disorders ◽  
Upper Paleolithic ◽  
Developmental Changes ◽  
Single Factor ◽  
Developmental Abnormalities ◽  
Low Probability ◽  
Developmental Variants

Diverse developmental abnormalities and anomalous features are evident in the PleistoceneHomofossil record, varying from minor but rare dental, vertebral, and carpal variants to exceptional systemic disorders. There are currently 75 documented anomalies or abnormalities from 66 individuals, spanning the Pleistocene but primarily from the Late Pleistocene Middle and Upper Paleolithic with their more complete skeletal remains. The expected probabilities of finding these variants or developmental disorders vary from <5% to <0.0001%, based on either recent human incidences or relevant Pleistocene sample distributions. Given the modest sample sizes available for the skeletal or dental elements in question, especially if the samples are appropriately limited in time and geography, the cumulative multiplicative probability of finding these developmental changes is vanishingly small. These data raise questions regarding social survival abilities, differing mortuary treatments of the biologically unusual, the role of ubiquitous stress among these Pleistocene foragers, and their levels of consanguinity. No single factor sufficiently accounts for the elevated level of these developmental variants or the low probability of finding them in the available paleontological record.

scholarly journals Losses of female song with changes from tropical to temperate breeding in the New World blackbirds

2009 ◽  
Vol 276 (1664) ◽  
pp. 1971-1980 ◽  
Author(s):  
J. Jordan Price ◽  
Scott M. Lanyon ◽  
Kevin E. Omland
Keyword(s):  
Sexual Selection ◽  
New World ◽  
Female Song ◽  
Complex Song ◽  
Evolutionary Changes ◽  
Apparent Relationship ◽  
Song Production ◽  
Selection For ◽  
The Tropics

Birds in which both sexes produce complex songs are thought to be more common in the tropics than in temperate areas, where typically only males sing. Yet the role of phylogeny in this apparent relationship between female song and latitude has never been examined. Here, we reconstruct evolutionary changes in female song and breeding latitude in the New World blackbirds (Icteridae), a family with both temperate and tropical representatives. We provide strong evidence that members of this group have moved repeatedly from tropical to temperate breeding ranges and, furthermore, that these range shifts were associated with losses of female song more often than expected by chance. This historical perspective suggests that male-biased song production in many temperate species is the result not of sexual selection for complex song in males but of selection against such songs in females. Our results provide new insights into the differences we see today between tropical and temperate songbirds, and suggest that the role of sexual selection in the evolution of bird song might not be as simple as we think.

scholarly journals ACE2, angiotensin 1-7 and skeletal muscle: review in the era of COVID-19

2020 ◽  
Vol 134 (22) ◽  
pp. 3047-3062
Author(s):  
Koichi Yamamoto ◽  
Hikari Takeshita ◽  
Hiromi Rakugi
Keyword(s):  
Skeletal Muscle ◽  
Transmembrane Protein ◽  
Renin Angiotensin System ◽  
Protective Role ◽  
Potential Contribution ◽  
Angiotensin Converting Enzyme 2 ◽  
Multiple Organs ◽  
Potential Association ◽  
Entry Receptor

Abstract Angiotensin converting enzyme-2 (ACE2) is a multifunctional transmembrane protein recently recognised as the entry receptor of the virus causing COVID-19. In the renin–angiotensin system (RAS), ACE2 cleaves angiotensin II (Ang II) into angiotensin 1-7 (Ang 1-7), which is considered to exert cellular responses to counteract the activation of the RAS primarily through a receptor, Mas, in multiple organs including skeletal muscle. Previous studies have provided abundant evidence suggesting that Ang 1-7 modulates multiple signalling pathways leading to protection from pathological muscle remodelling and muscle insulin resistance. In contrast, there is relatively little evidence to support the protective role of ACE2 in skeletal muscle. The potential contribution of endogenous ACE2 to the regulation of Ang 1-7-mediated protection of these muscle pathologies is discussed in this review. Recent studies have suggested that ACE2 protects against ageing-associated muscle wasting (sarcopenia) through its function to modulate molecules outside of the RAS. Thus, the potential association of sarcopenia with ACE2 and the associated molecules outside of RAS is also presented herein. Further, we introduce the transcriptional regulation of muscle ACE2 by drugs or exercise, and briefly discuss the potential role of ACE2 in the development of COVID-19.

scholarly journals A legal paradigm shift towards climate justice in the Anthropocene

2020 ◽  
Vol 11 (1) ◽  
pp. 44-68
Author(s):  
Sam Adelman ◽  
Keyword(s):  
Paradigm Shift ◽  
Legal Theory ◽  
Environmental Law ◽  
Climate Justice ◽  
Potential Contribution ◽  
International Environmental Law ◽  
Main Driver ◽  
Business As Usual ◽  
Ecological Catastrophe

Business as usual is widely acknowledged as the main driver of ecological collapse and climate breakdown, but less attention is paid to the role of law as usual as an impediment to climate justice. This article analyses how domestic and international environmental law facilitate injustices against living entities and nature. It calls for a paradigm shift in legal theory, practice and teaching to reflect the scale and urgency of the unfolding ecological catastrophe. Section 2 outlines the links between climatic harms and climate injustices. This is followed by discussions of unsustainable law and economic development in sections 3 and 4. Section 5 examines the potential contribution of new materialist legal theory in bringing about a legal paradigm shift that reflects the jurisgenerative role of nature in promoting climate justice.

scholarly journals Inferring recent evolutionary changes in speech sounds

2021 ◽  
Vol 376 (1824) ◽  
Author(s):  
Steven Moran ◽  
Nicholas A. Lester ◽  
Eitan Grossman
Keyword(s):  
Language Contact ◽  
Language Evolution ◽  
Speech Sounds ◽  
Theme Issue ◽  
Short Term ◽  
The Past ◽  
Evolutionary Changes ◽  
The One ◽  
The Impact

In this paper, we investigate evolutionarily recent changes in the distributions of speech sounds in the world's languages. In particular, we explore the impact of language contact in the past two millennia on today's distributions. Based on three extensive databases of phonological inventories, we analyse the discrepancies between the distribution of speech sounds of ancient and reconstructed languages, on the one hand, and those in present-day languages, on the other. Furthermore, we analyse the degree to which the diffusion of speech sounds via language contact played a role in these discrepancies. We find evidence for substantive differences between ancient and present-day distributions, as well as for the important role of language contact in shaping these distributions over time. Moreover, our findings suggest that the distributions of speech sounds across geographic macro-areas were homogenized to an observable extent in recent millennia. Our findings suggest that what we call the Implicit Uniformitarian Hypothesis, at least with respect to the composition of phonological inventories, cannot be held uncritically. Linguists who would like to draw inferences about human language based on present-day cross-linguistic distributions must consider their theories in light of even short-term language evolution. This article is part of the theme issue ‘Reconstructing prehistoric languages’.

scholarly journals Alternative Splicing of Transcription Factors' Genes: Beyond the Increase of Proteome Diversity

2009 ◽  
Vol 2009 ◽  
pp. 1-6 ◽  
Author(s):  
David Talavera ◽  
Modesto Orozco ◽  
Xavier de la Cruz
Keyword(s):  
Transcription Factors ◽  
Alternative Splicing ◽  
Expression Patterns ◽  
Developmental Changes ◽  
Functional Families ◽  
Transcription Regulators ◽  
Alternatively Spliced ◽  
The Impact ◽  
Human And Mouse

Functional modification of transcription regulators may lead to developmental changes and phenotypical differences between species. In this work, we study the influence of alternative splicing on transcription factors in human and mouse. Our results show that the impact of alternative splicing on transcription factors is similar in both species, meaning that the ways to increase variability should also be similar. However, when looking at the expression patterns of transcription factors, we observe that they tend to diverge regardless of the role of alternative splicing. Finally, we hypothesise that transcription regulation of alternatively spliced transcription factors could play an important role in the phenotypical differences between species, without discarding other phenomena or functional families.

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