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Topic Review
Apis mellifera
The current knowledge about viruses of the Western honey bee, Apis mellifera.
  • 1.8K
  • 02 Nov 2020
Topic Review
PET Biomarkers in Mitochondrial Dysfunction
There is a need to disentangle the etiological puzzle of age-related neurodegenerative diseases, whose clinical phenotypes arise from known, and as yet unknown, pathways that can act distinctly or in concert. Enhanced sub-phenotyping and the identification of in vivo biomarker-driven signature profiles could improve the stratification of patients into clinical trials and, potentially, help to drive the treatment landscape towards the precision medicine paradigm. The rapidly growing field of neuroimaging offers valuable tools to investigate disease pathophysiology and molecular pathways in humans, with the potential to capture the whole disease course starting from preclinical stages. Positron emission tomography (PET) combines the advantages of a versatile imaging technique with the ability to quantify, to nanomolar sensitivity, molecular targets in vivo. There is an increasing body of literature implicating dysfunction of mitochondria and endoplasmic reticulum dynamics, energy metabolism and oxidative stress within the molecular paradigm of age-related neurodegenerative diseases. The development of novel PET radioligands enables the in vivo investigation of mitochondrial and ER dysfunction in age-related neurodegenerative diseases.
  • 1.8K
  • 21 Feb 2021
Topic Review
Homo-Oligomeric Proteins
Protein homo-oligomerization is a very common phenomenon, and approximately half of proteins form homo-oligomeric assemblies composed of identical subunits. Many proteins have a natural tendency to self-associate into homo-oligomeric protein complexes, also termed homomers, which are composed of two or more identical subunits. According to the estimation, 30–50% of all proteins oligomerize. In addition, analysis of protein crystal structures demonstrated that roughly 45% of eukaryotic proteins and 60% of prokaryotic proteins that are deposited as single polypeptide chains also exist in a form of homo-oligomeric complex. 
  • 1.8K
  • 23 Sep 2021
Topic Review
(1,3;1,4)-β-D-Glucans
(1,3;1,4)-β-D-Glucans, also named as mixed-linkage glucans, are unbranched non-cellulosic polysaccharides containing both (1,3)- and (1,4)-β-linkages. The linkage ratio varies depending upon species origin and has a significant impact on the physicochemical properties of the (1,3;1,4)-β-D-glucans.
  • 1.8K
  • 24 Sep 2021
Topic Review
Beneficial health properties of common natural phenolic acids
Phenolic acids comprise a group of natural compounds that are present in a wide range of herbs and other species of the plant kingdom. This work focuses on the most common natural occurring phenolic acids (caffeic, carnosic, ferulic, gallic, p-coumaric, rosmarinic, vanillic) and gives a summary of their recently reported health related effects that mainly link to their antioxidant properties. A number of in vitro and in vivo animal studies has been screened by the authors who report on most important research findings on each individual phenolic acid (or natural mixtures of them) while also formulating a number of conclusions and recommendations for future work in this scientific field.
  • 1.8K
  • 24 Oct 2020
Topic Review
Biological Activities of Chlorogenic Acids
The chlorogenic acids (CGAs) are a class of phenolic compounds widely distributed in various plants sources such as fruits, vegetables, coffee beans, tea, apples, and wine. CGAs are esters of quinic acid (QA) and one trans-cinnamic acid residue such as caffeic acid (CA), p-coumaric acid (p-CoA), and ferulic acid (FA), which are known as caffeoylquinic acids (CQAs), p-coumaroylquinic acids (p-CoQAs) and feruloylquinic acid (FQAs).
  • 1.8K
  • 10 Jun 2022
Topic Review
Cardiac Glycosides
Cardiac glycosides (CG’s) are naturally occurring biologically active small molecules, used to diagnose a diversity of heart diseases such as congestive heart failure and cardiac arrhythmia. The story of CG’s started over 100 years ago when Sir William Withering reported the use of foxglove plant for treating “dropsy” associated with congestive heart failure and the foxglove plant (Digitalis purpurea) was still in the use for the extraction of Digoxin, a cardiac glycoside used to treat congestive heart failures (Johnson., 2012). The core structure of CGs comprises a steroid nucleus attached to a five-membered lactone ring (cardenolide) or six-membered lactone rings (bufadienolides) along with sugar moieties. Major plant-derived CGs were obtained from plant families of Apocynaceae, Scrophulariaceae, and Asparagaceae (Thevitia neriifolia, Neerium oleander, Digitalis purpurea, Digitalis lanata, Urginea maritime, and Strophanthus kombe). Structurally, all these contain a core steroid nucleus connected with sugar moiety at C3 position and lactone moiety at C17 position (Figure 1.3). The pharmacological significance of all the CG’s lies in the core steroid confirmation that contains A/B and C/D cis- portions and the properties such as pharmacokinetics and pharmacodynamics lie between the confined sugars molecules (Pongrakhananon., 2013). Apart from the plant sources, CG’s were also isolated from several animal species such as bufadienolide was isolated from frogs, and also mammalian tissues contain a cardiac glycoside which is similar to endogenous digitalis (Melero et al., 2000). Quite a few studies have conveyed that the human body does contain a lot more CG’s in different parts. For example, the plasma membrane contains Ouabain and Proscillaridin A and human urine contains digoxin and marinobufagenin whereas human lenses consist of 19-norbufalin (Schoner and Scheiner-Bobis., 2007). In the year 1785, William Withering was the first person to use a digitalis compound from Digitalis purpurea to treat congestive heart failures. Currently, Digoxin is used for treating congestive heart failures. The mechanism of action of Digoxin is that it can inhibit the sodium-potassium pump (Na+/K+-ATPase). Living organisms maintain more percentage of K+ within the cell and less percentage of Na+. However, the scenario at the outside of the cell is quite opposite to the intracellular conditions where a high percentage of Na+ and less percentage of K+ will be maintained. Hence, there is a concentration incline that exists between the outside and inside cellular environments, which will be maintained by sodium-potassium pump. The Na+/K+-ATPase is recognized as a transmembrane protein whose functions are to maintain ionic balance in the heart tissue. Na+/K+-ATPase utilizes ATP as the whole energy source, to exchange two K+ ions inside the cell and pushes three Na+ ions outside to maintain intra cellular homeostasis. Also, Na+/K+-ATPase transports glucose and amino acids by keeping less concentration of Na+ within the cell and helps in the maintenance of electrochemical incline. The increment of the Na+ level inside the cell retort to CGs fortifies the ion exchange mechanism. This leads to the expansion of intracellular Ca2+ percentage which therefore promotes organelle instances such as myocardial contractibility, and generates optimistic inotropic effects in the heart cell with CGs (Kaplan., 2002).  
  • 1.8K
  • 12 Aug 2020
Topic Review
Connective Tissue
This is an overview of the main molecular components, structural organization and main functions of the connective tissue, which is constitutively present in tissues and organs of the body. Connective tissue is known to provide structural and functional “glue” properties to other tissues. It contains cellular and molecular components that are arranged in several dynamic organizations. Connective tissue is the focus of numerous genetic and nongenetic diseases. Genetic diseases of the connective tissue belong to minority or rare diseases, but no less important than the nongenetic diseases.
  • 1.8K
  • 13 Nov 2020
Topic Review
Nuda
Nuda is a class of ctenophores or comb jellies. The class contains a single family, Beroidae, with two genera, Beroe and Neis, and the group is more commonly referred to as the "beroids". They are distinguished from other comb jellies by the complete absence of tentacles, in both juvenile and adult stages. Beroe is found in all the world's oceans and seas, and the monotypic Neis occurs only near Australia; all beroids are free-swimmers that form part of the plankton.
  • 1.8K
  • 19 Oct 2022
Topic Review
Cadmium and Lead Exposure
This entry provides information relevant to public health policy regarding advisable exposure limits for cadmium (Cd) and lead (Pb) that have no biologic role in humans. All of their perceptible effects are toxic. These metals exist in virtually all foodstuffs. Foods which are frequently consumed in large quantities such as cereals, rice, potatoes and vegetables contribute the most to total intake of these metals. Because Cd and Pb exposure are highly prevalent, even a small increase in disease risk can result in a large number of people affected by a disease that is preventable. Public measures to minimize environmental pollution and the food-chain transfer of Cd and Pb are required to prevent Cd- and Pb- related ailments and mortality as are risk reduction measures that set a maximally permissible concentration of Cd and Pb in staple food to the lowest achievable levels.
  • 1.8K
  • 29 Oct 2020
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