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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
The Cannabis Terpenes
Terpenes are the primary constituents of essential oils and are responsible for the aroma characteristics of cannabis. Together with the cannabinoids, terpenes illustrate synergic and/or entourage effect and their interactions have only been speculated in for the last few decades. Hundreds of terpenes are identified that allude to cannabis sensory attributes, contributing largely to the consumer’s experiences and market price. They also enhance many therapeutic benefits, especially as aromatherapy.
  • 1.4K
  • 16 Dec 2020
Biography
Karl Schwarzschild
Karl Schwarzschild (9 October 1873 – 11 May 1916) was a Germany physicist and astronomer. He was also the father of astrophysicist Martin Schwarzschild. Schwarzschild provided the first exact solution to the Einstein field equations of general relativity, for the limited case of a single spherical non-rotating mass, which he accomplished in 1915, the same year that Einstein first introduced g
  • 1.4K
  • 01 Dec 2022
Topic Review
Oral Cancer and Diet
Oral cancer, included within head and neck cancer, is the sixth most common malignant neoplasm in the world. The main etiological factors are tobacco and alcohol, although currently, diet is considered an important determinant for its development. Several dietary nutrients have specific mechanisms of action, contributing to both protection against cancer and increasing the risk for development, growth, and spread. Foods such as fruits, vegetables, curcumin, and green tea can reduce the risk of oral cancer, while the so-called pro-inflammatory diet, rich in red meat and fried foods, can enhance the risk of occurrence. Dietary factors with a protective effect show different mechanisms that complement and overlap with antioxidant, anti-inflammatory, anti-angiogenic, and anti-proliferative effects. 
  • 1.4K
  • 29 Apr 2021
Topic Review
Endogenous Retroviruses Activity in Mouse
Endogenous retroviruses (ERVs) are genetic elements resulting from relics of ancestral infection of germline cells, now recognized in human as cofactors in the etiology of several complex diseases as neurodevelopmental disorders. Autism spectrum disorders, attention deficit hyperactivity disorders, and schizophrenia are neurodevelopmental disorders, currently attributed to the interplay among genetic vulnerability, environmental risk factors, and maternal immune activation. The role of ERVs in human embryogenesis, their intrinsic responsiveness to external stimuli, and the interaction with the immune system support the involvement of ERVs in the derailed neurodevelopmental process. Although definitive proofs that ERVs are involved in neurobehavioral alterations are still lacking, both preclinical models and human studies indicate that the abnormal expression of ERVs could represent a neurodevelopmental disorders-associated biological trait.
  • 1.4K
  • 30 Oct 2020
Topic Review
Human Neural Stem Cell Systems
       Building and functioning of the human brain requires the precise orchestration and execution of myriad molecular and cellular processes, across a multitude of cell types and over an extended period of time. Neural Stem Cells (NSCs) represent the heart of these processes, since they increase the pool of neural progenitors and are the founders of all the neural progeny which will constitute the adult human brain.
  • 1.4K
  • 30 Oct 2020
Topic Review
Chemistry and Biosynthesis of Apigenin
Apigenin, a natural bioactive flavonoid widely present in medicinal plants, functional foods, vegetables and fruits, exerts protective effects in models of neurological disorders and cardiovascular diseases and most of these effects are attributed to its antioxidant action.
  • 1.4K
  • 05 Nov 2021
Topic Review
Galectin-3 in Cardiovascular Diseases
Galectin-3 (Gal-3) belongs to a lectin family, acting as a galactoside-binding protein involved in many biological processes, such as controlling cell–cell and cell–matrix interactions, adhesion, proliferation, apoptosis, pre-mRNA splicing, immunity and inflammation.
  • 1.4K
  • 22 Dec 2020
Topic Review
Skin Substitutes
The skin plays an important role in the maintenance of the human's body physiological homeostasis. It acts as a coverage that protects against infective microorganism or biomechanical impacts. Skin is also implied in thermal regulation and fluid balance. However, skin can suffer several damages that impede normal wound-healing responses and lead to chronic wounds. Since the use of autografts, allografts, and xenografts present source limitations and intense rejection associated problems, bioengineered artificial skin substitutes (BASS) have emerged as a promising solution to address these problems. The advances that have been produced on tissue engineering techniques have enabled improving and developing new arising skin substitutes. Despite this, currently available skin substitutes have many drawbacks, and an ideal skin substitute has not been developed yet. The translation of cell‐based arising skin substitutes to clinical application represents one of the critical challenges on tissue engineering and it has to be overcome with the aim of offering each patient the more efficient therapy that fits with his clinical case and allows him having a good quality of life.
  • 1.4K
  • 19 Dec 2020
Topic Review
Saproxylic Beetles
Saproxylic beetles are dependent on dead wood at any stage of their own development and at any stage of wood decomposition e.g. mycetophages on wood-decay fungi. This group of saproxylic beetles has become a frequently used as a bioindicator of forest biodiversity.
  • 1.4K
  • 03 Jul 2021
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