How Hierarchical Structures Impact on Competition

Stackelberg models for hierarchical oligopolistic markets with a homogenous product were studied by researchers extensively. The goal of this paper is to extend the classical solution in closed form of the Stackelberg model for a general hierarchical structures composed by firms arranged into groups of different hierarchical levels.Hierarchical structures, multi-level Stackelberg equilibrium, Nash-Cournot equilibrium

Антивирусный эффект нового конъюгата пурина LAS-131 в отношении вируса простого герпеса 1 типа (Herpesviridae: Alphaherpesvirinae: Simplexvirus: Human alphaherpesvirus 1) in vitro

Introduction. Herpes simplex viruses type 1 (HSV-1) are extremely widespread throughout the world and, similar to other herpesviruses, establish lifelong persistent infection in the host. Reactivating sporadically, HSV-1 elicits recurrences in both immunocompetent and immunocompromised individuals and can cause serious diseases (blindness, encephalitis, generalized infections). The currently available antiherpetic drugs that aimed mainly at suppressing replication of viral DNA are not always effective enough, for example, due to the development of drug resistance. As we showed earlier the newly discovered compound LAS-131 exhibits the strong and highly selective inhibitory activity against HSV-1, including strain resistant to acyclovir (selective index, SI = 63). The presence of LAS-131 at a concentration of 20 μg/ml leads to a decrease in the titer of HSV-1 (strain L2) by 4 lg in a one round of HSV-1 replication. Material and methods. To establish the step(s) of the virus life cycle that is sensitive to the action of LAS-131, we have applied a widely used approach, that made it possible to determine how long the addition of a compound can be postponed before it loses its antiviral activity (time-of-addition assay), and to compare this indicator with the crucial time of application of inhibitors with a well-known mechanism of action (in cell culture). Results. It has been shown for the first time that LAS-131 retains a pronounced antiviral effect when introduced into the experimental system no later than 9 hours post-infection (p.i.). However, LAS-131 does not affect the release of HSV-1 from the cell. Discussion. Together with published data on the termination of the synthesis of viral DNA 9–12 h after the adsorption in a cell culture infected with HSV with a high multiplicity (≥1 PFU/cell), our results suggest that LAS-131 interferes the life cycle of HSV-1 during synthesis of viral DNA. Further studies of the mechanism of action are necessary to establish definitely the biological target for this compound,. © 2020 Izdatel'stvo Meditsina. All rights reserved

Synthesis of Pyrimidine Conjugates with 4-(6-Amino-hexanoyl)-7,8-difluoro-3,4-dihydro-3-methyl-2H-[1,4] benzoxazine and Evaluation of Their Antiviral Activity

A series of pyrimidine conjugates containing a fragment of racemic 7,8-difluoro-3,4-dihydro-3-methyl-2H-[1,4]benzoxazine and its (S)-enantiomer attached via a 6-aminohexanoyl fragment were synthesized by the reaction of nucleophilic substitution of chlorine in various chloropyrimidines. The structures of the synthesized compounds were confirmed by1H,19F, and 13 C NMR spectral data. Enantiomeric purity of optically active derivatives was confirmed by chiral HPLC. Antiviral evaluation of the synthesized compounds has shown that the replacement of purine with a pyrimidine fragment leads to a decrease in the anti-herpesvirus activity compared to the lead compound, purine conjugate. The studied compounds did not exhibit significant activity against influenza A (H1N1) virus. © 2022 by the authors. Licensee MDPI, Basel, Switzerland.Russian Science Foundation, RSF: 19-13-00231-PFunding: This research was funded by the Russian Science Foundation, grant number 19-13-00231-P

Phosphazide (nikavir) is a highly effective drug for the treatment of HIV/AIDS infection

Convincing evidence for high therapeutic activity and tolerability of Phosphazide in the treatment of HIV/AIDS- infection is given. Phosphazide is currently used in various regimens of highly active antiretroviral therapy, as well as in the HIV therapy in patients with simultaneously acquired chronic hepatitis C or tuberculosis. Therapeutic possibilities of Phosphazide were clearly manifested in the prevention of HIV transmission from mother to child. There is every reason to use Phosphazide in first-line antiretroviral therapy

Phosphazide (nikavir) is a highly effective drug for the treatment of HIV/AIDS infection

Federation Convincing evidence for high therapeutic activity and tolerability of Phosphazide in the treatment of HIV/AIDS-infection is given. Phosphazide is currently used in various regimens of highly active antiretroviral therapy, as well as in the HIV therapy in patients with simultaneously acquired chronic hepatitis C or tuberculosis. Therapeutic possibilities of Phosphazide were clearly manifested in the prevention of HIV transmission from mother to child. There is every reason to use Phosphazide in first-line antiretroviral therapy.</jats:p

Рецензии: Ф.И. Ершов. «История вирусологии от Д.И. Ивановского до наших дней». Научно-популярное издание. ГЭОТАР-Медиа, 279 страниц, 2020 года

A review for the book by F.I. Ershova History of Virology from D.I. Ivanovsky to the present day, publishing house GEOTAR-Media, 2020.Представлена рецензия на книгу Ф.И. Ершова История вирусологии от Д.И. Ивановского до наших дней издательства ГЭОТАР-Медиа, 2020 год

ANTIHIV/AIDS DRUG 6HP: ANTIVIRAL ACTIVITY, PRE-CLINICAL STUDY. EFFICIENCY IN ADULT HIV-INFECTED PATIENTS

The new domestic antiretroviral drug 6HP, which is ammonium-3’-azido-3’-deoxythymidine-5’-carbomoylphosphonate, shows a high level of anti-HIV activity in cultures of lymphoblastoid cells. In a organism, the 6HP is converted to azidothymidine, and the its pharmacokinetic parameters indicate a prolonged nature of action of this compound in vivo. It is an important indicator that allows to formulate optimal therapeutic regimens during clinical application of 6HP. The complex of its antiviral properties and the results of its exhaustive preclinica study, as well as the results of studying its safety and tolerability in adult HIV-infected patients, including important first data of its use as a specific therapeutic anti-HIV / AIDS drug, certainly indicate on its prospects and its usefulness in clinical use in patients with HIV infection, including as part of combination antiretroviral therapy.</jats:p

Reviews: F.I. Ershov. “History of Virology from D.I. Ivanovskay to the present day ”. Popular science edition. GEOTAR-Media, 279 p., 2020

A review for the book by F.I. Ershova History of Virology from D.I. Ivanovsky to the present day, publishing house GEOTAR-Media, 2020.</jats:p