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Topic Review
Pollen Quality Versus Quantity
Do bees really benefit from the conservation attempts made by us? A study performed recently showed that wild bees do not use plant species sown in wildflower seed mixtures as pollen sources, and it concluded that plant species currently promoted by agri-environmental schemes are not optimal for bees. I have taken a closer look at the factors that determined whether pollen was healthy food for the wild bee larvae or not and the results have led me to propose that a major shift in the perspective of what we considered as bee-friendly plants was definitely warranted.
  • 1.4K
  • 30 Oct 2020
Topic Review
Cortical Silent Period
The so-called cortical silent period (CSP) refers to the temporary interruption of electromyographic signal from a muscle following a motor-evoked potential (MEP) triggered by transcranial magnetic stimulation (TMS) over the primary motor cortex (M1). The neurophysiological origins of the CSP are debated. Previous evidence suggests that both spinal and cortical mechanisms may account for the duration of the CSP. However, contextual factors such as cortical fatigue, experimental procedures, attentional load, as well as neuropathology can also influence the CSP duration. The present paper summarizes the most relevant evidence on the mechanisms underlying the duration of the CSP, with a particular focus on the central role of the basal ganglia in the “direct” (excitatory), “indirect” (inhibitory), and “hyperdirect” cortico-subcortical pathways to manage cortical motor inhibition. We propose new methods of interpretation of the CSP related, at least partially, to the inhibitory hyperdirect and indirect pathways in the basal ganglia. This view may help to explain the respective shortening and lengthening of the CSP in various neurological disorders.
  • 1.4K
  • 01 Jun 2021
Topic Review
Jellyfish Cassiopea andromeda
Cassiopea andromeda entered the Mediterranean from the Red Sea through the Suez Canal and colonized several areas of the basin. This species is an epibenthic scyphozoan with a maximum umbrella diameter of about 30 cm commonly found in tropical and subtropical shallow coastal ecosystems such as mangroves, estuaries, and sandy mudflats. This species has a metagenetic cycle with the following phases: planula, benthic polyp, ephyra, and adult medusa. The symbiotic relationship with dinoflagellates allows the jellyfish species to feed via direct predation and through photosynthesis by the zooxanthellae (mixotrophy).
  • 1.4K
  • 28 Feb 2022
Topic Review
Haemophilus Influenzae
Haemophilus influenzae (formerly called Pfeiffer's bacillus or Bacillus influenzae) is a Gram-negative, coccobacillary, facultatively anaerobic capnophilic pathogenic bacterium of the family Pasteurellaceae. The bacterium was argued by some to be the cause of influenza. H. influenzae was first described in 1892 by Richard Pfeiffer during an influenza pandemic when he incorrectly described Haemophilus influenzae as the causative microbe, which explains why the bacteria retains "influenza" in its name. H. influenzae is responsible for a wide range of localized and invasive infections, but influenza is caused by viruses. This species was the first free-living organism to have its entire genome sequenced.
  • 1.4K
  • 23 Nov 2022
Topic Review
Gangliosides and Ganglioside GD3-Binding Proteins
Ganglioside GD3 is a major ganglioside in neuronal progenitor cells. Highly sialylated gangliosides, GM1, GD1a, GD1b, GT1b are the main gangliosides in adult neurons. GD3 is implicated in cell attachment and cell-to-cell interaction during embryogenesis. Anti-ganglioside GD3 monoclonal antibody (clone:R24) coimmunoprecipitates heterotrimeric G protein Goα, GPI-anchored neuronal cell adhesion molecule TAG-1, Src-family kinase Lyn and Csk -binding protein Cbp from rat cerebellar granule cells. Ganglioside GD3 is involved in the migration of granule cells during the early stage of cerebellar development via these GD3-binding proteins.
  • 1.4K
  • 03 Apr 2023
Topic Review
Cecropins Gene Expression
Antimicrobial peptides (AMPs) are naturally occurring molecules that are utilized as an innate immune response in a variety of organisms. AMPs can be constitutively expressed, and/or their transcription may be upregulated following pathogenic infection. Cecropins (Cecs) are insect AMPs, generally active against Gram-negative bacteria and to a lesser extent, Gram-positive bacteria. Some have been demonstrated to also exhibit an antifungal activity as well as anti-inflammatory and anti-tumor properties. Cecs function by associating their N- and C-terminal helices to the cellular membrane. Polar residues interact with the lipid phosphates while the non-polar residues burrow into the membrane. At high concentrations, Cecs form carpet-like structures with detergent-like properties that result in cell death. At low concentrations, Cecs organize into oligomers that form pores through the cellular phospholipid layer, resulting in an electrolyte imbalance that causes cell death. 
  • 1.4K
  • 30 Jul 2020
Topic Review
Food Neophobia
Food neophobia is the tendency to reject or be reluctant to try new and unfamiliar foods. Due to the period of its occurrence, which falls in the years of early childhood, it can significantly affect the child’s food choices, shape taste preferences, and significantly influence the quality of the child’s diet. 
  • 1.4K
  • 26 Apr 2022
Topic Review
Cat Behavior and Cat–Human Interactions: Brief Introduction
This entry summarised what is known about domestic cat behaviour and cat-human relations and what still needs to be examined, listing unanswered questions and hypotheses. Below is a selection of the topics covered in the original review. An English version of reference "50" (in French) may be requested and e-mailed legally (by contract) from the author by individuals as long as the original reference will be cited in French.
  • 1.4K
  • 28 Oct 2021
Topic Review
Flowering Plant
Flowering plants are plants that bear flowers and fruits, and form the clade Angiospermae (/ˌændʒiəˈspɜːrmiː/), commonly called angiosperms. The term "angiosperm" is derived from the Greek words angeion ('container, vessel') and sperma ('seed'), and refers to those plants that produce their seeds enclosed within a fruit. They are by far the most diverse group of land plants with 64 orders, 416 families, approximately 13,000 known genera and 300,000 known species. Angiosperms were formerly called Magnoliophyta (/mæɡˌnoʊliˈɒfətə, -əˈfaɪtə/). Like gymnosperms, angiosperms are seed-producing plants. They are distinguished from gymnosperms by characteristics including flowers, endosperm within their seeds, and the production of fruits that contain the seeds. The ancestors of flowering plants diverged from the common ancestor of all living gymnosperms during the Carboniferous, over 300 million years ago, according to some genetic analyses but there is no fossil evidence for this. The closest fossil relatives of flowering plants are uncertain and contentious. The earliest angiosperm fossils are in the form of pollen around 134 million years ago during the Early Cretaceous. Over the course of the Cretaceous, angiosperms explosively diversified, becoming the dominant group of plants across the planet by the end of the period, corresponding with the decline and extinction of previously widespread gymnosperm groups. The origin and diversification of the angiosperms is often known as "Darwin's abominable mystery".
  • 1.4K
  • 09 Oct 2022
Topic Review Peer Reviewed
Molecular Aspects of Spike–ACE2 Interaction
A new betacoronavirus (CoV-2) is responsible for the pandemic of severe acute respiratory syndrome (SARS) that began in China at the end of 2019, today known as COronaVIrus Disease 2019 (COVID-19). Subsequent studies confirmed the human angiotensin-converting enzyme 2 (hACE2) as the main cell receptor of spike trimeric glycoprotein, located on the viral envelope, mediating the CoV-2 invasion into the host cells through the receptor-binding domain (RBD) of the spike. Computational analysis of the known experimental 3D structures of spike–ACE2 complexes evidenced distinguishing features in the molecular interactions at the RBD-cell receptor binding interface between CoV-2 and previous CoV-1. The spike represents a key target for drug design as well as an optimal antigen for RNA/viral vector vaccines and monoclonal antibodies in order to maximize prevention and therapy of COVID-19.
  • 1.4K
  • 13 Apr 2022
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