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Topic Review
Mechanism of Antibiotics Resistance
Bacterial drug resistance is rapidly developing as one of the greatest threats to human health. Bacteria will adopt corresponding strategies to crack the inhibitory effect of antibiotics according to the antibacterial mechanism of antibiotics, involving the mutation of drug target, secreting hydrolase, and discharging antibiotics out of cells through an efflux pump, etc. Bacteria are found to constantly evolve new resistance mechanisms to antibiotics, including target protective protein, changes in cell morphology, and so on, endowing them with multiple defense systems against antibiotics, leading to the emergence of multi-drug resistant (MDR) bacteria and the unavailability of drugs in clinics. 
  • 1.0K
  • 28 Sep 2022
Topic Review
Synthesis of the Coumarin Core
Coumarin compounds are attractive organic compounds with many practical applications. Among them there are compounds with biological activity, pharmaceuticals, agrochemicals, dyes, and optoelectronic materials. For this reason, enormous and continuous attempts were made to develop new synthetic pathways and protocols to facilitate the key cyclization reaction of heterocyclic ring and its regioselective functionalization. Of the numerous proposed reactions for the preparation of coumarins, those based on transition metal catalysts have been frequently used recently. Such processes as intramolecular and intermolecular hydroarylation of alkenes or alkynes can be mentioned among the most effective reactions proceeding via the activation of the C–H bond. Knowledge about the mechanistic foundations of catalytic processes seems to be of significant importance in order to improve them and simplify the conditions. Direct functionalization of the coumarin skeleton seems to be one of the more difficult tasks in recent times.
  • 1.0K
  • 23 Mar 2022
Topic Review
Honey and Propolis in Ocular Disease Treatment
Honey and propolis have recently become the key target of attention for treating certain diseases and promoting overall health and well-being. A high content of flavonoids and phenolic acids found in both honey and propolis contributes to the antioxidant properties to scavenge free radicals. Honey and propolis also exhibited antibacterial effects where they act in two ways, namely the production of hydrogen peroxide (H2O2) and gluconic acids following the enzymatic activities of glucose oxidase, which exerts oxidative damage on the bacteria. Additionally, the anti-inflammatory effects of honey and propolis are mainly by reducing proinflammatory factors such as interleukins and tumor necrosis factor alpha (TNF-α). Their effects on pain were discovered through modulation at a peripheral nociceptive neuron or binding to an opioid receptor in the higher center. The aforementioned properties of honey have been reported to possess potential therapeutic topical application on the exterior parts of the eyes, particularly in treating conjunctivitis, keratitis, blepharitis, and corneal injury. In contrast, most of the medicinal values of propolis are beneficial in the internal ocular area, such as the retina, optic nerve, and uvea. 
  • 1.0K
  • 02 Feb 2023
Topic Review
Ginseng against Respiratory Tract Infections
Ginseng has been reported to inhibit bacterial pathways, thereby killing bacteria indirectly. It has also been shown to protect the host from bacterial invasion.
  • 1.0K
  • 30 Sep 2021
Topic Review
Extracellular Vesicle
Extracellular vesicles (EVs) are constituted by a group of heterogeneous membrane vesicles secreted by most cell types that play a crucial role in cell–cell communication.
  • 1.0K
  • 25 Mar 2021
Topic Review
Thymoquinone
Thymoquinone (TQ), the chief active constituent of Nigella sativa (NS), shows very valuable biomedical properties such as antioxidant, antimicrobial, anticancer, anti-inflammatory, antihypertensive, hypoglycemic, antiparasitic and anti-asthmatic effects. Several studies have examined the pharmacological actions of TQ in the treatment of oral diseases but its potential role in periodontal therapy and regeneration is not yet fully defined.
  • 1.0K
  • 17 Dec 2020
Topic Review
Phytochemicals mitigate AD mitochondrial dysfunctions
Alzheimer’s disease (AD) is a progressive neurodegenerative disorder characterized by a decline in cognitive function and neuronal damage. Although the precise pathobiology of AD remains elusive, accumulating evidence suggests that mitochondrial dysfunction is one of the underlying causes of AD. Mutations in mitochondrial or nuclear DNA that encode mitochondrial components may cause mitochondrial dysfunction. In particular, the dysfunction of electron transport chain complexes, along with the interactions of mitochondrial pathological proteins are associated with mitochondrial dysfunction in AD. Mitochondrial dysfunction causes an imbalance in the production of reactive oxygen species, leading to oxidative stress (OS) and vice versa. Neuroin-flammation is another potential contributory factor that induces mitochondrial dysfunction. Phy-tochemicals or other natural compounds have the potential to scavenge oxygen free radicals and enhance cellular antioxidant defense systems, thereby protecting against OS-mediated cellular damage. Phytochemicals can also modulate other cellular processes, including autophagy and mitochondrial biogenesis.
  • 1.0K
  • 25 Mar 2021
Topic Review
Cobalt–Chromium Dental Alloys
Co–Cr dental alloys consist of Co, Cr and also other metals (e.g., gallium, iron, molybdenum, nickel, ruthenium, tungsten). Since the 1990s, regulations have emerged to protect European patients and also monitor recent scientific knowledge. The use of metals and, therefore, dental alloys has been highly regulated by directives and regulations. Europe has, therefore, developed a regulatory package to protect all players involved in alloys, whether they are metal producers, manufacturers of alloys and medical devices, healthcare professionals and patients. Objective information is provided about Co–Cr dental alloys, with regard to both the latest toxicological data and regulatory developments from 2020–2025. The release of metal ions and the problem of wear particles are also discussed. With the recent change of regulatory status of Co, it is necessary to know the many repercussions (economic, technical etc.) of their use precisely in order to then allow actors to modify their daily work. The legislative changes also bring the need to propose new alternatives to Co-Cr dental alloys.  
  • 1.0K
  • 21 Jan 2021
Topic Review
Nitrogen-Based Alkylating Anticancer Agents
Despite the significant progress in anticancer drug development over recent years, there is a vital need for newer agents with unique, but still effective, mechanisms of action in order to treat the disease, particularly the highly aggressive and drug resistant types. Alkylating agents, in particular nitrogen-based alkylators, are commonly used to treat hematological and solid malignancies; they exert their antineoplastic effects at all phases of the cell cycle and prevent reproduction of tumor cells. Certain alkylating agents have been designed to be more lipophilic, enabling the compound to penetrate the cell and enhance its alkylating activity against tumors. This review details the evolution of currently available alkylating agents and their profiles, with a focus on nitrogen-based alkylating agents, as important anticancer therapy strategies.
  • 998
  • 27 Mar 2021
Topic Review
Nuclear factor-κB in Psoriasis
Nuclear factor-κB (NF-κB) plays a central role in psoriasis and canonical Wnt/β-catenin pathway blunts the immune-mediated inflammatory cascade in psoriasis. Adenosine A2A receptor activation blocks NF-κB and boosts the Wnt/β-catenin signaling. PDRN (Polydeoxyribonucleotide) is a biologic agonist of the A2A receptor and its effects were studied in an experimental model of psoriasis. Psoriasis-like lesions were induced by a daily application of imiquimod (IMQ) on the shaved back skin of mice for 7 days. Animals were randomly assigned to the following groups: Sham psoriasis challenged with Vaseline; IMQ animals challenged with imiquimod; and IMQ animals treated with PDRN (8 mg/kg/ip). An additional arm of IMQ animals was treated with PDRN plus istradefylline (KW6002; 25 mg/kg/ip) as an A2A antagonist. PDRN restored a normal skin architecture, whereas istradefylline abrogated PDRN positive effects, thus pointing out the mechanistic role of the A2A receptor. PDRN decreased pro-inflammatory cytokines, prompted Wnt signaling, reduced IL-2 and increased IL-10. PDRN also reverted the LPS repressed Wnt-1/β-catenin in human keratinocytes and these effects were abolished by ZM241385, an A2A receptor antagonist. Finally, PDRN reduced CD3+ cells in superficial psoriatic dermis. PDRN anti-psoriasis potential may be linked to a “dual mode” of action: NF-κB inhibition and Wnt/β-catenin stimulation.
  • 996
  • 03 Nov 2020
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