Encyclopedia
Scholarly Community
Encyclopedia
Entry
Video
Image
Journal
Book
News
About
Log in/Sign up
Submit
Entry
Video
Image
and
or
not
All
${ type }
To
Search
Subject:
All Disciplines
Arts & Humanities
Biology & Life Sciences
Business & Economics
Chemistry & Materials Science
Computer Science & Mathematics
Engineering
Environmental & Earth Sciences
Medicine & Pharmacology
Physical Sciences
Public Health & Healthcare
Social Sciences
Sort:
Most Viewed
Latest
Alphabetical (A-Z)
Alphabetical (Z-A)
Filter:
All
Topic Review
Biography
Peer Reviewed Entry
Video Entry
Topic Review
Synthesis of 3,4-Dihydropyrimidin(thio)one Containing Scaffold
The interest in 3,4-dihydropyrimidine-2(1H)-(thio)ones is increasing every day, mainly due to their paramount biological relevance. The Biginelli reaction is the classical approach to reaching these scaffolds, although the product diversity suffers from some limitations. In order to overcome these restrictions, two main approaches have been devised. The first one involves the modification of the conventional components of the Biginelli reaction and the second one refers to the postmodification of the Biginelli products. Both strategies have been extensively revised in this manuscript. Regarding the first one, initially, the modification of one of the components was covered. Although examples of modifications of the three of them were described, by far the modification of the keto ester counterpart was the most popular approach, and a wide variety of different enolizable carbonylic compounds were used; moreover, changes in two or the three components were also described, broadening the substitution of the final dihydropyrimidines. Together with these modifications, the use of Biginelli adducts as a starting point for further modification was also a very useful strategy to decorate the final heterocyclic structure.
1.2K
15 Aug 2022
Topic Review
Mechanism of Self-Healing Hydrogels
Polymeric hydrogels have drawn considerable attention as a biomedical material for their unique mechanical and chemical properties, which are very similar to natural tissues. Among the conventional hydrogel materials, self-healing hydrogels (SHH) are showing their promise in biomedical applications in tissue engineering, wound healing, and drug delivery. Additionally, their responses can be controlled via external stimuli (e.g., pH, temperature, pressure, or radiation). Identifying a suitable combination of viscous and elastic materials, lipophilicity and biocompatibility are crucial challenges in the development of SHH. Furthermore, the trade-off relation between the healing performance and the mechanical toughness also limits their real-time applications. Additionally, short-term and long-term effects of many SHH in the in vivo model are yet to be reported.
1.2K
09 Nov 2022
Topic Review
Fluorinated Drugs Approved by the FDA (2016–2022)
Fluorine is characterized by high electronegativity and small atomic size, which provide this molecule with the unique property of augmenting the potency, selectivity, metabolic stability, and pharmacokinetics of drugs. Fluorine (F) substitution has been extensively explored in drug research as a means of improving biological activity and enhancing chemical or metabolic stability. Selective F substitution onto a therapeutic or diagnostic drug candidate can enhance several pharmacokinetic and physicochemical properties such as metabolic stability and membrane permeation. The increased binding ability of fluorinated drug target proteins has also been reported in some cases. An emerging line of research on F substitution has been addressed by using 18F as a radiolabel tracer atom in the extremely sensitive methodology of positron emission tomography (PET) imaging.
1.2K
01 Sep 2023
Topic Review
Monoterpenes as Anticancer Therapeutic Agents
Terpenes—a diverse group of secondary metabolites—constitute the largest class of natural products abundant in almost every plant species.
1.2K
17 May 2021
Topic Review
Ethiopian Anticancer Plants
This entry provides an overview on the active phytochemical constituents of twenty-seven medicinal plants that are traditionally used to manage cancer in Ethiopia. It is compiled and discusses the potential anticancer, antiproliferative, and cytotoxic agents based on the types of secondary metabolites, such as terpenoids, phenolic compounds, alkaloids, steroids, and lignans. Among the anticancer secondary metabolites reported in this review, only few have been isolated from plants that are originated and collected in Ethiopia, and the majority of compounds are reported from plants belonging to different areas of the world. Thus, based on the available bioactivity reports, extensive and more elaborate ethnopharmacology-based bioassay-guided studies have to be conducted on selected traditionally claimed Ethiopian anticancer plants, which inherited from a unique and diverse landscape, with the aim of opening a way forward to conduct anticancer drug discovery program.
1.2K
21 Oct 2020
Topic Review
Covalent Inhibitors for Neglected Diseases
Neglected Tropical Diseases (NTD) is a group of 20 diseases affecting more than 1 billion people in the world, especially those living in poor communities of tropical areas. Caused by a variety of etiologic agents such as viruses, bacteria, and parasites, these diseases have a great impact on public health, with social and economic consequences to the affected populations.
1.1K
24 Jul 2023
Topic Review
G-Quadruplexes: Emerging Anticancer Roles
G-quadruplexes, a family of (thermodynamically and kinetically stable) tetraplex helices, are non-canonical secondary structures derived from guanine (G)-rich sequences of nucleic acids. G-quadruplexes were found to occur in functionally-important regions of the human genome, including the telomere tandem sequences, several proto-oncogene promoters and other regulatory regions, ribosomal DNA (rDNA), as well as mRNA sequences encoding for proteins with roles in tumorigenesis, thus establishing a clear connection between G-quadruplexes and known hallmarks of cancer. Stabilization of G-quadruplexes belonging to the above categories, by means of small-molecule intervention, has been correlated with a range of anticancer effects, which has led to classifying G-quadruplexes as novel potential targets in anticancer research. The most common ways in which G-quadruplexes are now understood to serve in an anticancer capacity are presented herein.
1.1K
03 Mar 2021
Topic Review
Plant-Based Indole Alkaloids
Indole (C8H7N) is a weakly basic molecule consisting of a pyrrole ring fused to a benzene nucleus, and ten π electrons move throughout the structure. The basic environment of indole alkaloids is thought to be caused by the delocalization of the lone pair of nitrogen electrons into the free circulation of the π electronic system. This results in indole becoming protonated at the C-3 position, which is thermodynamically more stable.Indole alkaloids have gained popularity due to their diverse pharmacological activities. Indole alkaloids have been identified in several prominent plant families, including Apocynaceae, Rubiaceae, Nyssaceae, and Loganiaceae, among others. Some of the identified indole alkaloid compounds have been highly effective in pre-clinical and clinical studies. Thousands of compounds containing the indole nucleus have been isolated from plant sources. Their pharmacological activities were assessed, with some now being examined in clinical trials and some already approved for therapeutic use in humans. Indole alkaloids are often characterized by their potent biological activities, which are relevant to the field of medicine, including anticancer, antibacterial, antiviral, antimalarial, antifungal, anti-inflammatory, antidepressant, analgesic, hypotensive, anticholinesterase, antiplatelet, antidiarrheal, spasmolytic, antileishmanial, lipid-lowering, antimycobacterial, and antidiabetic activities.
1.1K
27 Apr 2021
Topic Review
Antioxidant Compounds Extracted from Plants for Vegetable Oils
Oil oxidation is the main factor limiting vegetable oils’ quality during storage, as it leads to the deterioration of oil’s nutritional quality and gives rise to disagreeable flavors. These changes make fat-containing foods less acceptable to consumers. To deal with this problem and to meet consumer demand for natural foods, vegetable oil fabricators and the food industry are looking for alternatives to synthetic antioxidants to protect oils from oxidation. In this context, natural antioxidant compounds extracted from different parts (leaves, roots, flowers, and seeds) of medicinal and aromatic plants (MAPs) could be used as a promising and sustainable solution to protect consumers’ health.
1.1K
21 Nov 2022
Topic Review
Dendrimers in Biomedicine
Biomedicine represents one of the main study areas for dendrimers, which have proven to be valuable both in diagnostics and therapy, due to their capacity for improving solubility, absorption, bioavailability and targeted distribution. Molecular cytotoxicity constitutes a limiting characteristic, especially for cationic and higher-generation dendrimers. Antineoplastic research of dendrimers has been widely developed, and several types of poly(amidoamine) and poly(propylene imine) dendrimer complexes with doxorubicin, paclitaxel, imatinib, sunitinib, cisplatin, melphalan and methotrexate have shown an improvement in comparison with the drug molecule alone. The anti-inflammatory therapy focused on dendrimer complexes of ibuprofen, indomethacin, piroxicam, ketoprofen and diflunisal. In the context of the development of antibiotic-resistant bacterial strains, dendrimer complexes of fluoroquinolones, macrolides, beta-lactamines and aminoglycosides have shown promising effects. Regarding antiviral therapy, studies have been performed to develop dendrimer conjugates with tenofovir, maraviroc, zidovudine, oseltamivir and acyclovir, among others. Furthermore, cardiovascular therapy has strongly addressed dendrimers. Employed in imaging diagnostics, dendrimers reduce the dosage required to obtain images, thus improving the efficiency of radioisotopes. Dendrimers are macromolecular structures with multiple advantages that can suffer modifications depending on the chemical nature of the drug that has to be transported. The results obtained so far encourage the pursuit of new studies.
1.1K
11 Sep 2020
Topic Review
Ligands for Alzheimer’s Disease therapy
Despite tremendous research efforts at every level, globally, there is still a lack of effectivedrugs for the treatment of Alzheimer's disease (AD). The biochemical mechanisms of this devastatingneurodegenerative disease are not yet clearly understood. This review analyses the relevance ofmultiple ligands in drug discovery for AD as a versatile toolbox for a polypharmacological approachto AD. Herein, we highlight major targets associated with AD, ranging from acetylcholine esterase(AChE), beta-site amyloid precursor protein cleaving enzyme 1 (BACE-1), glycogen synthase kinase3 beta (GSK-3β), N-methyl-D-aspartate (NMDA) receptor, monoamine oxidases (MAOs), metal ions inthe brain, 5-hydroxytryptamine (5-HT) receptors, the third subtype of histamine receptor (H3 receptor),to phosphodiesterases (PDEs), along with a summary of their respective relationship to the diseasenetwork. In addition, a multitarget strategy for AD is presented, based on reported milestones in thisarea and the recent progress that has been achieved with multitargeted-directed ligands (MTDLs).Finally, the latest publications referencing the enlarged panel of new biological targets for AD relatedto the microglia are highlighted. However, the question of how to find meaningful combinations oftargets for an MTDLs approach remains unanswered.
1.1K
04 Aug 2020
Topic Review
Polymeric Nanoparticles in Cardiovascular Diseases
Nanoparticles, including biodegradable polymeric nanoparticles, are able to increase the efficiency and reduce the degradability of natural polyphenols, thus increasing their beneficial abilities in the target tissues. Resveratrol-, quercetin-, or curcumin-loaded polymeric nanoparticles have been shown to markedly reduce reactive oxygen species formation, the inflammatory process, apoptosis, lipid peroxidation, cardiac hypertrophy, and even to delay myocardium injury due to ischemia/reperfusion. Thus, polymeric nanoparticles represent a promising tool for the delivery of natural polyphenols to target tissues and enhance their desirable effects in the cardiovascular system.
1.1K
27 Oct 2020
Topic Review
Use of Kojic Acid in Cosmetics
In 1907, Saito discovered Kojic Acid (KA), a natural product; it has since become one of the most investigated skin-lightening agents. KA inhibits tyrosinase and has been commonly researched in the cosmetic industry. It is incorporated in many kinds of cosmetic products.
1.1K
23 Jun 2022
Topic Review
Applying CADD for Neurodegenerative Diseases
Neurodegenerative diseases (NDs) including Alzheimer’s disease, Parkinson’s disease, amyotrophic lateral sclerosis, and Huntington’s disease are incurable and affect millions of people worldwide. The development of treatments for this unmet clinical need is a major global research challenge. Computer-aided drug design (CADD) methods minimize the huge number of ligands that could be screened in biological assays, reducing the cost, time, and effort required to develop new drugs.
1.1K
07 May 2021
Topic Review
An Overview of PDE4 Inhibitors in Clinical Trials
Since the early 1980s, phosphodiesterase 4 (PDE4) has been an attractive target for the treatment of inflammation-based diseases. Several scientific advancements, by both academia and pharmaceutical companies, have enabled the identification of many synthetic ligands for this target, along with the acquisition of precise information on biological requirements and linked therapeutic opportunities. The transition from pre-clinical to clinical phase was not easy for the majority of these compounds, mainly due to their significant side effects, and it took almost thirty years for a PDE4 inhibitor to become a drug i.e., Roflumilast, used in the clinics for the treatment of chronic obstructive pulmonary disease. Three additional compounds have reached the market: Crisaborole for atopic dermatitis, Apremilast for psoriatic arthritis and Ibudilast for Krabbe disease.
1.1K
31 Aug 2022
Topic Review
Antagonists of the AT1receptor
Antagonists of the AT1receptor (AT1R) are beneficial molecules that can prevent the peptide hormone angiotensin II from binding and activating the specific receptor causing hypertension in pathological states.
1.1K
06 Jan 2021
Topic Review
Bioavailability of Lingonberry Polyphenols
Lingonberry (Vaccinium vitis-idaea) is less prevalent in the daily human diet because they are collected from the wild, and plant breeding of lingonberry is still on a small scale. Lingonberries are classed as “superfruits” with the highest content of antioxidants among berries and a broad range of health-promoting effects. Many studies showed various beneficial effects of lingonberries, such as anti-inflammatory, antioxidant, and anticancer activities. Lingonberries have been shown to prevent low-grade inflammation and diet-induced obesity in diabetic animals. Moreover, lingonberry intake has been associated with a beneficial effect on preventing and treating brain aging and neurodegenerative disorders.
1.1K
03 Jun 2021
Topic Review
Antibacterial Activity of Heterocyclic Compounds
Heterocyclic compounds are cyclic compounds which contain the atoms of two discrete elements as representative of their ring(s). They belong to one of the larger classes of organic compounds and also appear more valuable in different fields of chemistry.
1.1K
19 Dec 2022
Topic Review
Organoboron Compounds
The unique electron deficiency and coordination property of boron led to a wide range of applications in chemistry, energy research, materials science and the life sciences. The use of boron-containing compounds as pharmaceutical agents has a long history, and recent developments have produced encouraging strides. Boron agents have been used for both radiotherapy and chemotherapy. In radiotherapy, boron neutron capture therapy (BNCT) has been investigated to treat various types of tumors, such as glioblastoma multiforme (GBM) of brain, head and neck tumors, etc. Boron agents playing essential roles in such treatments and other well-established areas have been discussed elsewhere. Organoboron compounds used to treat various diseases besides tumor treatments through BNCT technology have also marked an important milestone. Following the clinical introduction of bortezomib as an anti-cancer agent, benzoxaborole drugs, tavaborole and crisaborole, have been approved for clinical use in the treatments of onychomycosis and atopic dermatitis. Some heterocyclic organoboron compounds represent potentially promising candidates for anti-infective drugs.
1.1K
25 Jun 2021
Topic Review
Cosmetic Science
In June 2020, the long-waited “Regulations on the Supervision and Administration of Cosmetics” (CSAR) was finally issued by the State Council of China, and this regulation will be implemented from 1 January 2021 [1]. CSAR is the first-time revision and replacement of the “Regulations on Hygiene Supervision of Cosmetics” (CHSR), which was published in 1989. During the past 30 years, substantial changes have happened both in the industry and in consumer needs, and the market has increased significantly. According to incomplete statistics, there are more than 1,800,000 valid cosmetic products in China currently in 2020. In addition, new techniques and approaches have appeared, and the concepts of supervision and administration have evolved.
1.0K
27 Dec 2020
Page
of
18
Featured Entry Collections
>>
Featured Books
>>
Encyclopedia of Social Sciences
Chief Editor:
Kum Fai Yuen
Encyclopedia of COVID-19
Chief Editor:
Stephen Bustin
Encyclopedia of Fungi
Chief Editor:
Luis V. Lopez-Llorca
Encyclopedia of Digital Society, Industry 5.0 and Smart City
Chief Editor:
Sandro Serpa
Entry
Video
Image
Journal
Book
News
About
Log in/Sign up
New Entry
New Video
New Images
About
Terms and Conditions
Privacy Policy
Advisory Board
Contact
Partner
ScholarVision Creations
Feedback
Top
Feedback
×
Help Center
Browse our user manual, common Q&A, author guidelines, etc.
Rate your experience
Let us know your experience and what we could improve.
Report an error
Is something wrong? Please let us know!
Other feedback
Other feedback you would like to report.
×
Did you find what you were looking for?
Love
Like
Neutral
Dislike
Hate
0
/500
Email
Do you agree to share your valuable feedback publicly on
Encyclopedia
’s homepage?
Yes, I agree. Encyclopedia can post it.
No, I do not agree. I would not like to post my testimonial.
Webpage
Upload a screenshot
(Max file size 2MB)
Submit
Back
Close
×