Gene therapy is the straightforward approach for the application of recent advances in molecular biology into clinical practice. One of the major obstacles in the development of gene therapy is the ...delivery of the effector to and into the target cell. Unfortunately, most methods commonly used in laboratory practice are poorly suited for clinical use. Viral vectors are one of the most promising methods for gene therapy delivery. Millions of years of evolution of viruses have resulted in the development of various molecular mechanisms for entry into cells, long-term survival within cells, and activation, inhibition, or modification of the host defense mechanisms at all levels. The relatively simple organization of viruses, small genome size, and evolutionary plasticity allow modifying them to create effective instruments for gene therapy approaches. This review summarizes the latest trends in the development of gene therapy, in particular, various aspects and prospects of the development of clinical products based on viral delivery systems.
Although there have been occasional reports of rare and low-level trichinellae infestation in beavers, no human cases of beaver-associated trichinellosis have been described. This report presents a ...possible case of human trichinellosis linked to beaver meat. Increasing consumption of beaver meat necessitates raising awareness of this potential source of trichinellosis.
Phylodynamics of Crimean Congo Hemorrhagic fever virus (CCHFV) genotype V in South Russia was analyzed using 244 partial (452–571 nt) sequences in all three genomic segments and 38 complete genomic ...sequences. Despite increased number of sequences, the Russian lineage of the European genotype V (commonly termed GtVa) was distinct from GtV isolates from Turkey and the Balkan countries. No geographic pattern was observed in phylogenetic subgrouping of CCHFV within South Russia. Identical isolates could be found at distant locations spaced by hundreds of kilometers, while relatively divergent viruses circulated in the same region. Full genome analysis indicated that reassortment events within GtVa occurred every few decades (median half-life of a non-reassortant node 30–40 years) and involved M and S segments. Therefore, in South Russia CCHFV represents a highly dynamic population of frequently reassorting viruses.
•A comprehensive analysis of Crimean Congo Hemorrhagic fever virus (CCHFV) phylodynamics in South Russia was conducted;•CCHFV represents a highly dynamic population of frequently reassorting viruses;•Reassortment events within the Russian lineage of the European genotype V (GtVa) occurred every 30-40 years;
Enterovirus 71 (EV71) is responsible for frequent large-scale outbreaks of hand, foot, and mouth disease worldwide and represent a major etiological agent of severe, sometimes fatal neurological ...disease. EV71 variants have been classified into three genogroups (GgA, GgB, and GgC), and the latter two are further subdivided into subgenogroups B1 to B5 and C1 to C5. To investigate the dual roles of recombination and evolution in the epidemiology and transmission of EV71 worldwide, we performed a large-scale genetic analysis of isolates (n = 308) collected from 19 countries worldwide over a 40-year period. A series of recombination events occurred over this period, which have been identified through incongruities in sequence grouping between the VP1 and 3Dpol regions. Eleven 3Dpol clades were identified, each specific to EV71 and associated with specific subgenogroups but interspersed phylogenetically with clades of coxsackievirus A16 and other EV species A serotypes. The likelihood of recombination increased with VP1 sequence divergence; mean half-lives for EV71 recombinant forms (RFs) of 6 and 9 years for GgB and GgC overlapped with those observed for the EV-B serotypes, echovirus 9 (E9), E30, and E11, respectively (1.3 to 9.8 years). Furthermore, within genogroups, sporadic recombination events occurred, such as the linkage of two B4 variants to RF-W instead of RF-A and of two C4 variants to RF-H. Intriguingly, recombination events occurred as a founding event of most subgenogroups immediately preceding their lineage expansion and global emergence. The possibility that recombination contributed to their subsequent spread through improved fitness requires further biological and immunological characterization.
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