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Topic Review
Vitamin D Scarcity in Arctic and  Tropical Peoples
Vitamin D metabolism differs among human populations because the species has adapted to different natural and cultural environments. Two environments are particularly difficult for the production of vitamin D by the skin: the Arctic, where the skin receives little solar UVB over the year; and the Tropics, where the skin is highly melanized and blocks UVB. In both cases, natural selection has favored the survival of those individuals who use vitamin D more efficiently or have some kind of workaround that ensures sufficient uptake of calcium and other essential minerals from food passing through the intestines. Vitamin D scarcity has either cultural or genetic solutions. Cultural solutions include consumption of meat in a raw or boiled state and extended breastfeeding of children. Genetic solutions include higher uptake of calcium from the intestines, higher rate of conversion of vitamin D to its most active form, stronger binding of vitamin D to carrier proteins in the bloodstream, and greater use of alternative metabolic pathways for calcium uptake. Because their bodies use vitamin D more sparingly, indigenous Arctic and Tropical peoples can be misdiagnosed with vitamin D deficiency and wrongly prescribed dietary supplements that may push their vitamin D level over the threshold of toxicity.
  • 1.3K
  • 20 Oct 2022
Topic Review
Domesticated Plants and Animals of Austronesia
One of the major human migration events was the maritime settlement of the islands of the Indo-Pacific by the Austronesian peoples, believed to have started from at least 5,500 to 4,000 BP (3500 to 2000 BC). These migrations were accompanied by a set of domesticated, semi-domesticated, and commensal plants and animals transported via outrigger ships and catamarans that enabled early Austronesians to thrive in the islands of Maritime Southeast Asia (also known as 'Island Southeast Asia'), Near Oceania (Melanesia), Remote Oceania (Micronesia and Polynesia), Madagascar , and the Comoros Islands. They include crops and animals believed to have originated from the Hemudu and Majiabang cultures in the hypothetical pre-Austronesian homelands in mainland China , as well as other plants and animals believed to have been first domesticated from within Taiwan, Maritime Southeast Asia, and New Guinea. Some of these plants are sometimes also known as "canoe plants", especially in the context of the Polynesian migrations. Domesticated animals and plants introduced during historic times are not included.
  • 1.3K
  • 25 Oct 2022
Topic Review
Secretory Trichomes of Tillandsia cyanea
The bromeliad Tillandsia cyanea Linden ex K. Koch, with its vibrant pink inflorescences, is a well-known ornamental plant all over the world. This epiphytic bromeliad possesses complex trichomes (peltate trichomes) that are capable of producing and exuding a polysaccharide-based secretion (mucilage) with high affinity for water. This observation indicates that T. cyanea - and probably many other bromeliads - might have more intricate strategies to cope with water availability than previously thought.
  • 1.3K
  • 09 Nov 2020
Topic Review
Smart ECM-Based Electrospun Biomaterials
Electrospinning is a well-known technique to produce fibers that mimic the three dimensional microstructural arrangements of the extracellular matrix fibers. Natural and synthetic polymers are used in the electrospinning process; moreover, a blend of them provides composite materials that have demonstrated the potential advantage of supporting cell function and adhesion. Recently, the decellularized extracellular matrix (dECM), which is the noncellular component of tissue that retains relevant biological cues for cells, has been evaluated as a starting biomaterial to realize composite electrospun constructs. The properties of the electrospun systems can be further improved with innovative procedures of functionalization with biomolecules. Among the various approaches, great attention is devoted to the “click” concept in constructing a bioactive system, due to the modularity, orthogonality, and simplicity features of the “click” reactions. Here, we provide an overview of current approaches that can be used to obtain biofunctional composite electrospun biomaterials and propose a design of a smart ECM-based electrospun system suitable for skeletal muscle tissue regeneration.
  • 1.3K
  • 24 Sep 2020
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".
  • 1.3K
  • 09 Oct 2022
Topic Review
Lingua Geographica
Geographic tongue, also known by several other terms,[note 1] is a condition of the mucous membrane of the tongue, usually on the dorsal surface. It is a common condition, affecting approximately 2–3% of the general population. It is characterized by areas of smooth, red depapillation (loss of lingual papillae) which migrate over time. The name comes from the map-like appearance of the tongue, with the patches resembling the islands of an archipelago. The cause is unknown, but the condition is entirely benign (importantly, it does not represent oral cancer), and there is no curative treatment. Uncommonly, geographic tongue may cause a burning sensation on the tongue, for which various treatments have been described with little formal evidence of efficacy.
  • 1.3K
  • 26 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.
  • 1.2K
  • 13 Apr 2022
Topic Review
Probiotic Lactobacillus in Anti-Ageing
Probiotics are defined as live microorganisms that confer a health benefit on the host when administered adequately. The most common probiotic strains are associated with the genera Lactobacillus and Bifidobacterium. Recent advancements have witnessed significant achievements in using Lactobacillus during animal studies in ageing models.
  • 1.3K
  • 22 Dec 2021
Topic Review
PANoptosis
Consideration of the totality of biological effects from cell death in multiple studies has led to the conceptualization of PANoptosis, a unique inflammatory cell death pathway that integrates components from other cell death pathways. PANoptosis is implicated in driving innate immune responses and inflammation and cannot be individually accounted for by pyroptosis, apoptosis, or necroptosis alone. PANoptosis is regulated by multifaceted macromolecular complexes called PANoptosomes.
  • 1.3K
  • 02 Jun 2022
Topic Review
Non-Viral Vectors in Gene Therapy
Efficient delivery of genetic material into cells is a critical process to translate gene therapy into clinical practice. In this sense, the increased knowledge acquired during past years in the molecular biology and nanotechnology fields has contributed to the development of different kinds of non-viral vector systems as a promising alternative to virus-based gene delivery counterparts. 
  • 1.3K
  • 28 Jul 2021
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