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The quinoid pigment echinochrome A isolated from the sea urchin Scaphechinus mirabilis, the product of its oxidation dehydroechinochrome, and structurally similar antiviral agent oxolin were tested for their ability to inhibit plaque formation induced by herpes simplex virus type 1 (HSV-1) in Vero cells. The tested compounds showed significant anti-HSV-1 activity, mainly due to their direct effect on viral particles and on virus attachment to cells. The antiviral efficacy of the test compounds increased in the following order: oxolin→echinochrome A→dehydroechinochrome.

Herpes simplex virus (HSV) infections, the incidence of which is still widespread throughout the world, are actualizing the search and development of new, more effective antiherpetic drugs. The development of multifunctional drug delivery systems, including liposome-based ones, has become a relevant and attractive concept in nanotechnology. The ability of complexes of κ- and Σ-carrageenans (CRGs)—sulfated polysaccharides of red algae, with echinochrome A (Ech), as well as the liposomal form of the Σ-CRG/Ech complex—to inhibit different stages of HSV-1 infection in Vero cells was studied. By quantum chemical calculations, it was shown that CRG forms stable complexes with Ech. We have shown that complexes of κ-CRG/Ech and Σ-CRG/Ech exhibit highest virucidal activity with a selectivity index (SI) of 270 and 350, respectively, and inhibition of virus-cell interaction (SI of 83 and 32, respectively). The liposomal form of the Σ-CRG/Ech complex after virus adsorption and penetration to cells effectively reduced the HSV-1 plaque formation. The virus-inhibiting activity of the liposomal form of the Σ-CRG/Ech complex was three times higher than that of the Σ-CRG/Ech complex itself. Obtaining CRGs/Ech complexes and their liposomal forms can become the basis of a successful strategy for the development of promising antiherpetic drugs.

The Hantaan orthohantavirus (genovariant Amur–AMRV) is a rodent-borne zoonotic virus, it is the causative agent of haemorrhagic fever with renal syndrome in humans. The currently limited therapeutic options require the development of effective anti-orthohantavirus drugs. The ability of native fucoidan from Fucus evanescens (FeF) and its enzymatically prepared high-molecular-weight (FeHMP) and low-molecular-weight (FeLMP) fractions to inhibit different stages of AMRV infection in Vero cells was studied. The structures of derivatives obtained were determined using nuclear magnetic resonance (NMR) spectroscopy. We found that fucoidan and its derivatives exhibited significant antiviral activity by affecting the early stages of the AMRV lifecycle, notably virus attachment and penetration. The FeHMP and FeLMP fractions showed the highest anti-adsorption activity by inhibiting AMRV focus formation, with a selective index (SI) &gt, 110, FeF had an SI of ~70. The FeLMP fraction showed a greater virucidal effect compared with FeF and the FeHMP fraction. It was shown by molecular docking that 2O-sulphated fucotetrasaccharide, a main component of the FeLMP fraction, is able to bind with the AMRV envelope glycoproteins Gn/Gc and with integrin β3 to prevent virus–cell interactions. The relatively small size of these sites of interactions explains the higher anti-AMRV activity of the FeLMP fraction.

Herpes simplex virus type 1 (HSV-1) is one of the most prevalent pathogens worldwide requiring the search for new candidates for the creation of antiherpetic drugs. The ability of sea urchin spinochromes&mdash, echinochrome A (EchA) and its aminated analogues, echinamines A (EamA) and B (EamB)&mdash, to inhibit different stages of HSV-1 infection in Vero cells and to reduce the virus-induced production of reactive oxygen species (ROS) was studied. We found that spinochromes exhibited maximum antiviral activity when HSV-1 was pretreated with these compounds, which indicated the direct effect of spinochromes on HSV-1 particles. EamB and EamA both showed the highest virucidal activity by inhibiting the HSV-1 plaque formation, with a selectivity index (SI) of 80.6 and 50.3, respectively, and a reduction in HSV-1 attachment to cells (SI of 8.5 and 5.8, respectively). EamA and EamB considerably suppressed the early induction of ROS due to the virus infection. The ability of the tested compounds to directly bind to the surface glycoprotein, gD, of HSV-1 was established in silico. The dock score of EchA, EamA, and EamB was &minus, 4.75, &minus, 5.09, and &minus, 5.19 kcal/mol, respectively, which correlated with the SI of the virucidal action of these compounds and explained their ability to suppress the attachment and penetration of the virus into the cells.

For the first time in African studies, conducted in Russia, the authors generalize and analyze the experience of centuries-old socialization practices in conjunction with the latest trends in this field. The problem of childhood has long occupied an independent place in the wide range of scientific disciplines that to some extent examine the image of man. It is difficult to avoid standard phrases expressing the possibilities of studying this stage of a person’s life, all those institutions, rules and codes, traditions, customs and innovations, models of morality and culture that are laid in this unique period of life when mental essence and civil image are formed. One of the main factors of the sociocultural nature that forms a young African is the influence of community norms and traditions of values that hold down a person and tie him to a given social group. In a traditional African society, the family has always been (and remains) the main institution of socialization; for the individual it has been that very sociocultural field within which the personality has been formed. In a large African family, the problem boiles down to the development of a very simple model of behavior – to follow the precepts of the ancestors, to reproduce their experience and skills, to preserve their way of life. The formation of more or less close relations of the child with adults who take care of him/her – parents, relatives, friends of the family, etc. – turns the latter into the main agents of his/her socialization. At present, one of the most important factors of socialization is schooling. Often children combine study and work; in Africa, child labor is the most common in the world. Despite the official legal prohibition of the use of child labor, family control plays a key role in its practice. It depends mainly on the family whether the child continues to study or leaves school and engages only in labor activity, the latter primarily within the family. The problem of reducing and eradicating child labor has both moral, ethical, and socio-economic aspects. To solve it, it is necessary to expand access to schooling, increase incomes by achieving greater opportunities for employment and earnings for adult workers, and change attitudes towards child labor on the part of the whole society, and at the same time observe the laws regulating its use.

The aim of this study was to examine the in vitro antioxidant and antiviral activities of echinochrome A and echinochrome-based antioxidant composition against tick-borne encephalitis virus (TBEV) and herpes simplex virus type 1 (HSV-1). The antioxidant composition, which is a mixture of echinochrome A, ascorbic acid, and &alpha, tocopherol (5:5:1), showed higher antioxidant and antiviral effects than echinochrome A. We suppose that echinochrome A and its composition can both directly affect virus particles and indirectly enhance antioxidant defense mechanisms in the hosting cell. The obtained results allow considering the echinochrome A and the composition of antioxidants on its basis as the promising agents with the both antioxidant and antiviral activities.

Four 1,4-naphthoquinone dithioglucoside derivatives based on natural polyhydroxy-1,4-naphthoquinones were synthesized. These thioglucosides were screened for their antiradical and antiviral activity in vitro. Antiradical activity of tested compounds was determined by the 2,2-diphenyl-1-picrylhydrazyl radical scavenging assay. The anti-herpes simplex virus type 1 (anti-HSV-1) activity of thioglucosides was analyzed by the cytopathic effect inhibition assay and mode of antiviral action was determined by the addition of the tested compounds to uninfected cells, to the virus prior to infection, or to herpes-infected cells. Most effective inhibition of HSV-1 replication was observed at pretreatment of virus by the compounds (direct virucidal effect). The dithioglucoside conjugate with the single β-OH group and lipophilic ethyl substituent in naphthoquinone core showed the greatest antiviral activity.

Natalia G. Plekhova1,2, Larisa M. Somova1, Irina N. Lyapun1,2, Nadejda M. Kondrashova2, Natalia V. Krylova1, Galina N. Leonova1 and Euvgenii V. Pustovalov2 1Lab. Pathomorphlogy and Electron Microscopy, Institute of Epidemiology and Microbiology, Siberian Branch of the Russian Academy of Medical Sciences, Vladivostok, 2Lab. Electronic Microscopy and Processing of Images, Far Eastern Federal University, Vladivostok Russia