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Published in Michael Hehenberger, Zhi Xia, Huanming Yang, Our Animal Connection, 2020
Michael Hehenberger, Zhi Xia, Huanming Yang
The skin of some species contains the powerful poison tetrodotoxin, a neurotoxin similar to the pufferfish venom. These salamanders tend to be slow-moving and have bright warning coloration to advertise their toxicity. Tetrodotoxin is the most toxic nonprotein substance known. Ingestion of even a minute fragment of skin is deadly. Tetrodotoxin is a sodium channel blocker. It inhibits the firing of action potentials in neurons by binding to the voltage-gated sodium channels in nerve cell membranes and blocking the passage of sodium ions (responsible for the rising phase of an action potential) into the neuron. This prevents the nervous system from carrying messages and thus muscles from flexing in response to nervous stimulation.
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Published in Michael Hehenberger, Zhi Xia, Our Animal Connection, 2019
The skin of some species contains the powerful poison tetrodotoxin, a neurotoxin similar to the pufferfish venom. These salamanders tend to be slow-moving and have bright warning coloration to advertise their toxicity. Tetrodotoxin is the most toxic nonprotein substance known. Ingestion of even a minute fragment of skin is deadly. Tetrodotoxin is a sodium channel blocker. It inhibits the firing of action potentials in neurons by binding to the voltagegated sodium channels in nerve cell membranes and blocking the passage of sodium ions (responsible for the rising phase of an action potential) into the neuron. This prevents the nervous system from carrying messages and thus muscles from flexing in response to nervous stimulation.
Interlocked Systems in Catalysis and Switching
Published in Jubaraj Bikash Baruah, Principles and Advances in Supramolecular Catalysis, 2019
Sequential reactions leading to the movements of rings towards different positions on an axle of rotaxane coupled with a group transfer reaction are utilised in polypeptide synthesis in a selective manner. The interlocked DNA molecules forming a catenane-type structure act as catalysts for switchable cyclic catalytic reactions. The active and passive states of the DNA-catenane cause a catalytic reaction of luminol with hydrogen peroxide by modification of the catenanelike assembly of the two DNA. The catalyst passivation is done by coordination to a magnesium ion by one of the DNA rings, and activation is done by releasing a magnesium ion from the DNA by using blocker/displacer strands.
Carob extract attenuates brain and lung injury in rats exposed to waterpipe smoke
Published in Egyptian Journal of Basic and Applied Sciences, 2018
Mona Abdel-Rahman, Amira A. Bauomy, Fatma Elzahraa H. Salem, Mona Ahmed Khalifa
Wyss et al. [27] reported that amiodarone pass into the brain and it has an anticonvulsant and hypnotic effects. Moreover, amiodarone prolonged the sleeping time and behaved as central nervous system depressant drug in pentobarbital-induced sleeping in rat model [28]. Many reports attributed the anticonvulsant activity of amiodarone to its activity as a multiple ion-channel blocker drug which inhibit Na+, Ca2+ inward and K+ outward currents [28,29] . It well known that when action potentials depolarize the plasma membrane of the axon terminal, voltage-gated Ca2+ channels is open. This permits Ca2+ to diffuse down its concentration gradient into the cytoplasm, where it stimulates the release of neurotransmitters which stored in synaptic vesicles by exocytosis [30]. Because of the amiodarone is a calcium ion-channel blocker [29]; so the neurotransmitters release is inhibited and as the result their content is increased in brain which may explain the increment in neurotransmitters content in some time intervals in the present study.
A new Co(II) coordination polymer: crystal structure and treatment activity on viral myocarditis by reducing CVB3 virus burdens
Published in Inorganic and Nano-Metal Chemistry, 2020
Feierkaiti· Yushanjiang, Xierzhaman· Abudula, Qing-Shan Zhang
The design, synthesis and structural characterization of Schiff base complexes are still being vividly pursued their continuing development in the area of fundamental scientific study.[5–7] Schiff bases and their corresponding metal complexes have continued to enjoy extensive interest owing to their structural diversity and potentially wide-ranging applications such as those involving their anticancer, anticonvulsant, antitumor, antifungal, antibacterial, anti-tubercular, antioxidant, antimalarial, and anti‐inflammatory activities and in corrosion inhibition.[8–11] Due to such a wide range of applications, considerable effort is being directed to the development of new chelating Schiff base ligands. Metal complexes of sulfur‐and nitrogen‐containing ligands such as Schiff bases have been the subject of current and growing interest in the field of coordination chemistry because it has been shown that many of these complexes possess anticancer activity.[12–15] On the other hand, On the other hand, cobalt is an element of biological interest because its biological role is mainly focused on its presence in the active center of vitamin B12, which regulates indirectly the synthesis of DNA. Additionally, there are at least eight cobalt-dependent proteins. Cobalt is also involved in the co-enzyme of vitamin B12 and is used as a supplement of the vitamin. Since the first reported studies into the biological activity of Co complexes in 1952, many cobalt complexes of biological interest have been reported with the most structurally characterized showing antitumor, antiproliferative, antimicrobial and antifungal activity.[16–19] To combine the advances of Co ion and Schiff base ligand, in this study, we present the synthesis and characterization of a thiocyanato linked Co(II) coordination polymer [Co2L1(μ1,3-SCN)(η1SCN)]n (1) using potential multisite compartmental N,O donor Schiff base blocker ligand [N, N′-bis(3-methoxysalicylidenimino)-1,3-daminopropane] (H2L1) in presence of Co(OAc)2 and KSCN. Furthermore, the nanoparticles of complex 1 were prepared by a green grinding approach, which has good water dispersibility. In biological research, the treatment activity of nano 1 on myocarditis induced by CVB3 virus was evaluated. The results of RT-PCR indicated that nano 1 has an excellent inhibitory effect on the CVB3 virus loading. The data of the LVEF and LVFS also suggested nano 1 could exert protective effect cardiac functions. The results of potential binding models were obtained from molecular docking and pose scoring software to exhibit a possible binding site on VP1, which might provide a potential regulation mechanism for the ligand through a direct binding mode.