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Topic Review
Biochemical and Physiological Application of Pterin Photochemistry
Pterins are low-molecular weight heterocyclic compounds widely distributed in living organisms, primarily as reduced coenzymes. Structurally, pterins are a conjugated system of pyrazine and pyrimidine rings, the so-called pteridine, which is accompanied by a carbonyl group (C=O) at the C4 position and an amino group (NH2) at the C2 position. The pteridine structure is also characteristic of folates (folic acid and its derivatives) and flavins, or benzopteridines, which are derivatives of isoalloxazine. Folates are usually called “conjugated pterins” since they possess a para-aminobenzoilglutamine residue, whereas pterins are called “unconjugated pterins”. In addition to pterin, folates include a para-aminobenzoic acid (p-ABA) residue and one to five glutamic acid (Glu) residues.
  • 1.1K
  • 13 Dec 2022
Topic Review
The Role of microRNAs in Neurological Pathologies
MicroRNAs (miRNAs) are small non-coding RNA molecules that are 18–25 nucleotides long (22 nucleotides on average) and involved in the transcriptional and post-transcriptional regulation of gene expression by RNA interference, which is of great interest to molecular biologists, geneticists, and biochemists. These molecules are mainly present intracellularly, but there is also an extracellular (circulating) microRNA fraction. The existence and functions of more than 2500 human miRNAs are known. 
  • 1.1K
  • 29 Aug 2023
Topic Review
Endothelial Dysfunction
Any damage to the endothelial cells leads to the interruption of the barrier, an increased permeability, and an inflow of molecules that generate inflammatory response. Pulmonary endothelium is able to generate bioactive molecules and/or to use compounds present in the cell to reduce the effects of toxic stimuli and restore its conditions. If the damage is particularly extensive, the endothelium cannot tackle it and its permeability undergoes some alterations. The pulmonary endothelial barrier is completely destroyed in the case of chronic lung damages. A typical example of chronic inflammation of the alveolus-capillary unit is represented by virus infections.
  • 1.1K
  • 18 Jan 2022
Topic Review
Multienzymatic Processes Involving Baeyer–Villiger Monooxygenases
Baeyer–Villiger monooxygenases (BVMOs) are flavin-dependent oxidative enzymes capable of catalyzing the insertion of an oxygen atom between a carbonylic Csp2 and the Csp3 at the alpha position, therefore transforming linear and cyclic ketones into esters and lactones. These enzymes are dependent on nicotinamides (NAD(P)H) for the flavin reduction and subsequent reaction with molecular oxygen. BVMOs can be included in cascade reactions, coupled to other redox enzymes, such as alcohol dehydrogenases (ADHs) or ene-reductases (EREDs), so that the direct conversion of alcohols or α,β-unsaturated carbonylic compounds to the corresponding esters can be achieved. 
  • 1.1K
  • 11 May 2021
Topic Review
Land Use for Critical Cemeteries in Central Ecuador
Cemeteries are sites for the final disposal of human bodies that constitute a source of contamination of soil and water as a result of the cadaveric decomposition generated. In addition, land use conflicts were encountered in the cemetery grounds. It is concluded that the existing cemeteries should be subjected to more detailed environmental analysis and subsequently should be treated as security landfills in the closure and post-closure stage. Also, it has been concluded that the cemeteries should not be located in urban or peri-urban areas.
  • 1.1K
  • 11 Feb 2022
Topic Review
Marine Resources for the Omicron SARS-CoV-2 Variant
In November of 2021, a recently evolved variant of SARS-CoV-2, omicron, was discovered. In just one month, omicron has spread to more than 89 countries resulting in a rapid rise in cases and a new wave of infections. With over 46 mutations, omicron brings concern to the public health and may be able to infect at a greater capacity than previous strains. Although able to infect double vaccinated and previously infected individuals, the booster vaccine may prove promising. However, more research is needed to fully elucidate the key function of each mutation and to better develop effective drugs. Marine resources may be a promising drug discovery avenue to investigate. Through viral entry blockade and preventing viral replication and protein synthesis, metabolites produced from marine organisms may be promising against the evolving SARS-CoV-2.
  • 1.1K
  • 29 Jun 2022
Topic Review
ADAM Proteases
Limited proteolysis reactions by a disintegrin and metalloproteases (ADAMs) are key events in several paracrine signalling pathways. Therefore, ADAM proteases might also represent master-switches during hepatic fibrosis and other pathophysiologic events. Known and potential fibrosis-associated pathways regulated by ADAM proteases are discussed and the current knowledge on ADAM protease implication in several disease states is reviewed.
  • 1.1K
  • 13 Jul 2023
Topic Review
Prophylaxis and Treatment Against Kp
Klebsiella pneumoniae (Kp) is an opportunistic pathogen and the leading cause of healthcare-associated infections, mostly affecting subjects with compromised immune systems or suffering from concurrent bacterial infections. However, the dramatic increase in hypervirulent strains and the emergence of new multidrug-resistant clones resulted in Kp occurrence among previously healthy people and in increased morbidity and mortality, including neonatal sepsis and death across low- and middle-income countries. As a consequence, carbapenem-resistant and extended spectrum β-lactamase-producing Kp have been prioritized as a critical anti-microbial resistance threat by the World Health Organization and this has renewed the interest of the scientific community in developing a vaccine as well as treatments alternative to the now ineffective antibiotics. Capsule polysaccharide is the most important virulence factor of Kp and plays major roles in the pathogenesis but its high variability (more than 100 different types have been reported) makes the identification of a universal treatment or prevention strategy very challenging. However, less variable virulence factors such as the O-Antigen, outer membrane proteins as fimbriae and siderophores might also be key players in the fight against Kp infections.
  • 1.1K
  • 10 May 2021
Topic Review
Sphingolipids in Central Nervous System
Bioactive lipids are a newly defined class of lipids that are actively involved in the regulation of a variety of cellular events. As the name indicates, these molecular factors are subjected to action at the arrival of a specific stimulus and undergo subsequent transitions to cope up with the insult. Among these bioactive lipids, sphingolipids have emerged as distinctive mediators of various cellular processes, ranging from cell growth and proliferation to cellular apoptosis, executing immune responses to regulating inflammation. Recent studies have made it clear that sphingolipids, their metabolic intermediates (ceramide, sphingosine-1-phosphate, and N-acetyl sphingosine), and enzyme systems (cyclooxygenases, sphingosine kinases, and sphingomyelinase) harbor diverse yet interconnected signaling pathways in the central nervous system (CNS), orchestrate CNS physiological processes, and participate in a plethora of neuroinflammatory and neurodegenerative disorders.
  • 1.1K
  • 05 Aug 2021
Topic Review
Ischemic Stroke and Excitotoxicity
Stroke is a relevant cause of death, disability and dementia worldwide. In ischemic stroke, excitotoxicity is the main mechanism of neuronal death in the penumbra area, a potentially recoverable tissue surrounding the irreversibly damaged infarct core. In excitatory neurons, scaffold protein PSD-95 plays a central role in neuronal function but also survival/death choices. Thus, this protein is a promising target for development of neuroprotective strategies for stroke and other pathologies similarly associated to excitotoxicity.
  • 1.1K
  • 13 Dec 2021
Topic Review
Oxi-Inflamm-Aging Related Cardiorenal Syndrome
Kidney failure is also a major cause of cardiovascular morbidity and mortality. Indeed, epidemiological studies have demonstrated that chronic kidney disease (CKD) is a significant risk for cardiovascular events independently of classical risk. 
  • 1.1K
  • 06 Jan 2022
Topic Review
Impact of the Renin-Angiotensin System on Neurodegenerative Diseases
The renin-angiotensin-aldosterone system (RAS) is an endocrine axis which has important peripheral physiological functions (blood pressure and cardiovascular homeostasis, water and sodium balance, and systemic vascular resistance). In addition to the systemic action of RAS, recent research highlights its paracrine and autocrine actions in many tissues, including the central nervous system. The complex is located intracellularly and is involved in various intracellular processes.
  • 1.1K
  • 04 Nov 2022
Topic Review
The Fibroblast Growth Factor Receptors
Breast cancer (BC) is the most frequent form of malignancy and second only to lung cancer as cause of deaths in women. Notwithstanding many progresses made in the field, metastatic BC has a very poor prognosis. As therapies are becoming more personalized to meet the needs of patients, a better knowledge of the molecular biology leading to the disease unfolds the possibility to project more precise compounds or antibodies targeting definite alteration at the molecular level and functioning on such cancer-causing molecules expressed in cancer cells of patients, or present as antigens on the surface of cancer cell membranes. Fibroblast growth factor receptor (FGFR) is one of such druggable targets, activated by its own ligands -namely the Fibroblast Growth Factors (FGFs). This pathway provides a vast range of interesting molecular targets pursued at different levels of clinical investigation.
  • 1.1K
  • 01 Nov 2020
Topic Review
Pharmacotherapeutic Approaches to Treatment of Muscular Dystrophies
Muscular dystrophies are a heterogeneous group of genetic muscle-wasting disorders that are subdivided based on the region of the body impacted by muscle weakness as well as the functional activity of the underlying genetic mutations. A common feature of the pathophysiology of muscular dystrophies is chronic inflammation associated with the replacement of muscle mass with fibrotic scarring. With the progression of these disorders, many patients suffer cardiomyopathies with fibrosis of the cardiac tissue. Anti-inflammatory glucocorticoids represent the standard of care for Duchenne muscular dystrophy, the most common muscular dystrophy worldwide; however, long-term exposure to glucocorticoids results in highly adverse side effects, limiting their use. Thus, it is important to develop new pharmacotherapeutic approaches to limit inflammation and fibrosis to reduce muscle damage and promote repair.
  • 1.1K
  • 18 Dec 2023
Topic Review
Insulin in Health and Disease
Insulin is a polypeptide hormone mainly secreted by β cells in the islets of Langerhans of the pancreas. The hormone potentially coordinates with glucagon to modulate blood glucose levels; insulin acts via an anabolic pathway, while glucagon performs catabolic functions. Insulin regulates glucose levels in the bloodstream and induces glucose storage in the liver, muscles, and adipose tissue, resulting in overall weight gain. The modulation of a wide range of physiological processes by insulin makes its synthesis and levels critical in the onset and progression of several chronic diseases. Although clinical and basic research has made significant progress in understanding the role of insulin in several pathophysiological processes, many aspects of these functions have yet to be elucidated. This review provides an update on insulin secretion and regulation, and its physiological roles and functions in different organs and cells, and implications to overall health. We cast light on recent advances in insulin-signaling targeted therapies, the protective effects of insulin signaling activators against disease, and recommendations and directions for future research.
  • 1.1K
  • 30 Jun 2021
Topic Review
γ-aminobutyric Acid and Barley Seedlings
It has been revealed that high NaCl stress (>60 mmol L−1) induced phenolics accumulation in barley seedlings, with γ-aminobutyric acid (GABA) playing a key role. Interestingly, low NaCl stimulus (20 mmol L−1) enhancing phenolics synthesis and growth of barley seedlings was also reported recently. Hence, exogenous GABA and its bio-synthesis inhibitor 3-mercaptopropionic acid (3-MP) were applied to reveal the mechanism of GABA regulating phenolics metabolism in barley seedlings treated with 20 mmol L−1 NaCl. The contents of total phenolics and flavonoids significantly increased by 11.64% and 14.52% under NaCl, respectively. The addition of GABA further increased phenolics and flavonoids contents, especially for gallic acid, protocatechuic acid, caffeic acid, and quercetin, compared with NaCl treatment. Simultaneously, GABA increased the activities and mRNA levels of phenylalanine ammonia lyase (PAL), cinnamic acid 4-hydroxylase (C4H), and 4-coumalyl CoA ligase (4CL). The addition of 3-MP suppressed the above effects, except for increasing the protein levels of PAL, C4H, and 4CL. Low concentration of NaCl not only promoted growth, but also stimulated endogenous GABA metabolism to affect key enzymes activities and mRNA levels for phenolics synthesis in barley seedlings.
  • 1.1K
  • 15 Oct 2021
Topic Review
The Protein Corona
The prolific applicability of nanomaterials has made them a common citizen in biological systems, where they interact with proteins forming a biological corona complex. 
  • 1.1K
  • 14 Apr 2023
Topic Review
Polyphenols and its Natural Preservatives
The use of synthetic/artificial preservatives has become common and has not been widely accepted by consumers as they are aware of the fact that exposure to preservatives can lead to adverse effects on health, which is a major area of concern for researchers. Naturally occurring phenolic compounds appear to be extensively used as bio-preservatives to prolong the shelf life of the finished product. 
  • 1.1K
  • 07 Oct 2023
Topic Review
Role of TRPA1 and TRPV1
TRPA1 and TRPV1 are structurally related thermosensitive cation channels and are often co-expressed in sensory nerve endings. TRPA1 and TRPV1 can also indirectly influence some, but not all, primary taste qualities via the release of substance P and calcitonin gene-related peptide (CGRP) from trigeminal neurons and their subsequent effects on CGRP receptor expressed in Type III taste receptor cells. Here, we will review the effect of some chemesthetic agonists of TRPA1 and TRPV1 and their influence on bitter, sour, and salt taste qualities.
  • 1.1K
  • 13 Apr 2021
Topic Review
Biological Effects of Fluorescein Photochemistry
Fluorescein is a fluorescent organic dye used as tracer, contrasting agent or a diagnostic tool in various fields of medicine and natural sciences in general.
  • 1.1K
  • 26 May 2022
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