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Topic Review
Blastula
The blastula (from Greek βλαστός (blastos), meaning "sprout") is a hollow sphere of cells, referred to as blastomeres, surrounding an inner fluid-filled cavity called the blastocoel formed during an early stage of embryonic development in animals. Embryo development begins with a sperm fertilizing an egg to become a zygote which undergoes many cleavages to develop into a ball of cells called a morula. Only when the blastocoel is formed does the early embryo become a blastula. The blastula precedes the formation of the gastrula in which the germ layers of the embryo form. A common feature of a vertebrate blastula is that it consists of a layer of blastomeres, known as the blastoderm, which surrounds the blastocoel. In mammals the blastula is referred to as a blastocyst. The blastocyst contains an embryoblast (or inner cell mass) that will eventually give rise to the definitive structures of the fetus, and the trophoblast, which goes on to form the extra-embryonic tissues. During the blastula stage of development, a significant amount of activity occurs within the early embryo to establish cell polarity, cell specification, axis formation, and to regulate gene expression. In many animals such as Drosophila and Xenopus, the mid blastula transition (MBT) is a crucial step in development during which the maternal mRNA is degraded and control over development is passed to the embryo. Many of the interactions between blastomeres are dependent on cadherin expression, particularly E-cadherin in mammals and EP-cadherin in amphibians. The study of the blastula and of cell specification has many implications in stem cell research and assisted reproductive technology. In Xenopus, blastomeres behave as pluripotent stem cells which can migrate down several pathways, depending on cell signaling. By manipulating the cell signals during the blastula stage of development, various tissues can be formed. This potential can be instrumental in regenerative medicine for disease and injury cases. In vitro fertilisation involves implantation of a blastula into a mother's uterus. Blastula cell implantation could serve to eliminate infertility.
  • 1.4K
  • 30 Nov 2022
Topic Review
Thapsigargin
Thapsigargin (Tg), a guaianolide-type sesquiterpene lactone, is abundant in the common Mediterranean weed Thapsia garganica (Apiaceae), known as “deadly carrot” due to its high toxicity to sheep and cattle.
  • 1.4K
  • 18 Jan 2021
Topic Review
Role of  Insects in Spread of  Foodborne Pathogens
Insects play a key role in European agroecosystems. Insects provide important ecosystem services and make a significant contribution to the food chain, sustainable agriculture, the farm-to-fork (F2F) strategy, and the European Green Deal. Edible insects are regarded as a sustainable alternative to livestock. 
  • 1.4K
  • 20 Feb 2023
Topic Review
Copper Complexes as Topoisomerases Inhibitors
Organometallics, such as copper compounds, are cancer chemotherapeutics used alone or in combination with other drugs. A group of copper complexes exerts an effective inhibitory action on topoisomerases, which participate in the regulation of DNA topology. Copper complexes of topoisomerase inhibitors work by different molecular mechanisms that have repercussions on the cell cycle checkpoints and death effectors. 
  • 1.4K
  • 14 Oct 2020
Topic Review
Gluten-Free Bread and Bakery Products Technology
Gluten intolerance is becoming more common in the population, and patients with this intolerance must follow a gluten-free diet. Bread and other bakery products are staple foods and pose a problem in a gluten-free diet due to their short shelf life and the need to replace gluten. Naturally gluten-free cereals and pseudocereals, but also milled legumes, seeds and nuts, are being increasingly used for the preparation of gluten-free baked goods.
  • 1.4K
  • 25 Feb 2022
Topic Review
Biomechanical Factors in Track and Field Sprint Start
In athletics sprint events, the block start performance can be fundamental to the outcome of a race. Several biomechanical determinants of sprinters have been identified. In the “Set” position, an anthropometry-driven block setting facilitating the hip extension and a rear leg contribution should be encouraged. At the push-off, a rapid extension of both hips and greater force production seems to be important. After block exiting, shorter flight times and greater propulsive forces are the main features of best sprinters. 
  • 1.4K
  • 13 Apr 2022
Topic Review
Helianthus Annuus
Helianthus annuus, the common sunflower, is a large annual forb of the genus Helianthus grown as a crop for its edible oil and edible fruits. This sunflower species is also used as wild bird food, as livestock forage (as a meal or a silage plant), in some industrial applications, and as an ornamental in domestic gardens. The plant was first domesticated in the Americas. Wild Helianthus annuus is a widely branched annual plant with many flower heads. The domestic sunflower, however, often possesses only a single large inflorescence (flower head) atop an unbranched stem. The name sunflower may derive from the flower's head's shape, which resembles the sun. Sunflower seeds were brought to Europe from the Americas in the 16th century, where, along with sunflower oil, they became a widespread cooking ingredient.
  • 1.4K
  • 19 Oct 2022
Topic Review
Cannabis Sativa Revisited
Critically ill patients with sepsis require a multidisciplinary approach, as this situation implies multiorgan distress, with most of the bodily biochemical and cellular systems being affected by the condition. Moreover, sepsis is characterized by a multitude of biochemical interactions and by dynamic changes of the immune system. At the moment, there is a gap in our understanding of the cellular, genetic, and molecular mechanisms involved in sepsis. One of the systems intensely studied in recent years is the endocannabinoid signaling pathway, as light was shed over a series of important interactions of cannabinoid receptors with biochemical pathways, specifically for sepsis. Furthermore, a series of important implications on inflammation and the immune system that are induced by the activity of cannabinoid receptors stimulated by the delta-9-tetrahydrocannabinol (Δ9-THC) and cannabidiol (CBD) have been noticed. One of the most important is their ability to reduce the biosynthesis of pro-inflammatory mediators and the modulation of immune mechanisms. Different studies have reported that cannabinoids can reduce oxidative stress at mitochondrial and cellular levels. In detail, the entry shows the important mechanisms modulated by the endocannabinoid signaling pathway, as well as of the molecular and cellular links it has with sepsis. At the same time, the possible implications of cannabinoids in the most important biological pathways involved in sepsis, such as inflammation, redox activity, immune system, and epigenetic expression will be presented.
  • 1.4K
  • 04 Jul 2022
Topic Review
Pacific Temperate Rainforests (WWF Ecoregion)
The Pacific temperate rainforests ecoregion of North America is the largest temperate rain forest ecoregion on the planet as defined by the World Wildlife Fund (other definitions exist). The Pacific temperate rain forests lie along the western side of the Pacific Coast Ranges along the Pacific Northwest Coast of North America from the Prince William Sound in Alaska through the British Columbia Coast to Northern California, and are part of the Nearctic ecozone, as also defined by the World Wildlife Fund. The Pacific temperate rain forests are characterized by a high amount of rainfall, in some areas more than 300 cm (10 ft) per year and moderate temperatures in both the summer and winter months (10–24 °C or 50–75 °F). This ecoregion is a subregion of the Cascadia bioregion. These rain forests occur in a number of ecoregions, which vary in their species composition, but are predominantly of conifers, sometimes with an understory of broadleaf trees, ferns and shrubs. In the WWF's system, sub-ecoregions of the Pacific Temperate Rain Forests Ecoregion are the Northern Pacific coastal forests, Haida Gwaii, British Columbia mainland coastal forests, Central Pacific coastal forests, Central and Southern Cascades forests, Klamath-Siskiyou forests, and Northern California coastal forests ecoregions. The forests in the north contain predominantly Sitka spruce and western hemlock, while those in the coastal forests are home as well to coast redwood (Sequoia sempervirens), coast Douglas-fir (Pseudotsuga menziesii), western redcedar and shore pine. Notably, the three tallest species of trees are found here. Dense growths of epiphytes and mosses cover the trees, and lush vegetation is present everywhere. Hardwood trees such as the bigleaf maple and the alder are also common, especially at lower elevations and along stream banks, and are vital to the ecosystem, in part because of their nitrogen fixing.
  • 1.4K
  • 03 Nov 2022
Topic Review
L-Citrulline
L-citrulline (CIT) is an organic compound and a non-essential amino acid, and the body can synthesize it endogenously. Diet is a poor source of CIT and endogenous synthesis the its main source in the body. Watermelon is the principal source of that amino acid in the diet; the name citrulline comes from Citrullus lanatus (Thunb.), the scientific name for watermelon. CIT concentration in watermelon depends on the type of cultivir and usually ranges between 0.7 and 3.6 g/kg of fresh weight. CIT is present in both the flesh and in the ring.
  • 1.4K
  • 06 May 2021
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