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Вирусные заболевания центральной нервной системы.

Вирусные заболевания центральной нервной системы (СНС) представляют собой значительное бремя для здоровья людей во всем мире. Сложность этих заболеваний зависит от большого числа различных нейтропических вирусов, различных маршрутов проникновения CNS, вирусного трофизма и иммунной системы. Используя сочетание патологических данных человека и экспериментальных моделей животных, мы начали обнаруживать многие из механизмов, которые вирусы используют для проникновения в ЦНС и вызывают болезни. В этом обзоре освещается ряд нейротропических вирусов, которые заражают ОВН, и рассматриваются средства,

Совпадение в аннотации оригинала
Virus-induced diseases of the central nervous system (CNS) represent a significant burden to human health worldwide. The complexity of these diseases is influenced by the sheer number of different neurotropic viruses, the diverse routes of CNS entry, viral tropism, and the immune system. Using a combination of human pathological data and experimental animal …

Enabling the 'host jump': structural determinants of receptor-binding specificity in influenza A viruses.

The recent emergence of the H7N9 avian influenza A virus and its ability to infect humans emphasize the epidemic and pandemic potential of these viruses. Interspecies transmission is the result of many factors, which ultimately lead to a change in the host tropism of the virus. One of the key factors involved is a shift in the receptor-binding specificity of the virus, which is mostly determined by mutations in the viral haemagglutinin (HA). In this Review, we discuss recent crystallographic studies that provide molecular insights into HA-host receptor interactions that have enabled several in…

[The parasitism characteristics of the causative agent of melioidosis in the host cells].

The electron microscopic study of the damaged areas of the lungs, liver, spleen and lymph nodes of guinea pigs infected with two P. pseudomallei virulent strains C-141 and 100 has revealed that this organism is a facultative intracellular parasite and exhibits tropism to reticuloendothelial cells of the body, parasitizing both in "professional" phagocytes (mononuclear, phagocytes, polymorphonuclear leukocytes) and "nonprofessional" phagocytes (capillary endotheliocytes, splenic and lymph-node reticulocytes). In the course of their intracellular development P. pseudomallei have been shown to fo…

Notes on the pathogenesis of enterovirus infections. Observations, experiments, and speculations.

Despite extensive investigations over the last decades, several aspects of the pathogenesis of enterovirus infections in humans and animals are only poorly understood, such as the molecular basis of virulence (in particular of neurovirulence), tissue tropisms (e.g. the precise site of initial virus replication in the human intestinal tract), and precipitating factors of paralytic disease ("disposition"). Studies on poliovirus myocarditis in man are reviewed. Unequivocal evidence on replication of poliovirus type 2 (strains MEF1 and Lansing) in newborn and suckling mice and on poliovirus myocar…

Cryptosporidium geckonae n. sp. (Apicomplexa: Cryptosporidiidae) in geckos.

BACKGROUND: Cryptosporidium is a globally prevalent parasite that infects the gastrointestinal tract of a large number of vertebrates. The C … SU rRNA, actin, HSP70 and COWP genes. Its biological characteristics, including oocyst size, tissue tropism and associated pathology, were investigated using light microscopy, electron microscopy and histological techniques. Experimental infections were performed to assess host specificity and infectivity. RESULTS: Phylogenetic analysis of the target gen …

Histomolecular profile of Helicobacter pylori strains circulating in Brazzaville (Congo).

BACKGROUND AND AIM: Helicobacter pylori (Hp) infection is a real public health problem in the Congo. We aimed study the histomolecular profi … n was determined using real-time PCR. PCR was also used to identify the Hp strains and assess their tropism in the gastric mucosa. Digestive symptoms, endoscopic lesions, and histopathological lesions associated with HP infection were studied. RESULTS: The incidence of Hp infection was 91%, with a female predominance of 52.75% and an average age of 46.32 …

Analysis of Medication Rules of Traditional Chinese Medicine for Malaria Treatment Based on Data Mining.

Objective To analyze the medication rules of traditional Chinese medicine (TCM) for malaria treatment.Methods Statistical analysis was conducted on the basic attributes of TCM drugs with regard to property, therapeutic methods, flavor, and meridian tropism. A complex network of TCM drug associations was constructed. Cluster analysis was applied to obtain the core drugs for malaria treatment. The Apriori algorithm was applied to analyze the association rules of these core drugs.Results A total of 357 herbs were used 3,194 times in 461 prescriptions for malaria treatment. Radix Glycyrrhizae (), …

A preliminary study of the localization of infectious laryngotracheitis virus glycoprotein E within specific peripheral blood lymphocytes.

Infectious laryngotracheitis virus (ILTV) DNA has been detected in blood fractions, but the cell phenotype with which the virus is associate … hickens exhibited fluorescence for ILTV gE. The results of this pilot study suggest that ILTV has a tropism for peripheral blood T and B cells. Further research is required to investigate whether these cells support ILTV productive replication. RESEARCH HIGHLIGHTSSelective tropism of ILTV for peripheral blood cells was demonstrated in acutely infected bir …

Establishment of a Reverse Genetic System from a Bovine Derived Influenza D Virus Isolate.

The ruminant-associated influenza D virus (IDV) has a broad host tropism and was shown to have zoonotic potential. To identify and characterize molecular viral determinants influencing the host spectrum of IDV, a reverse genetic system is required. For this, we first performed 5' and 3' rapid amplification of cDNA ends (RACE) of all seven genomic segments, followed by assessment of the 5' and 3' NCR activity prior to constructing the viral genomic segments of a contemporary Swiss bovine IDV isolate (D/CN286) into the bidirectional pHW2000 vector. The bidirectional plasmids were transfected in …

Characterization of novel microneme adhesive repeats (MAR) in Eimeria tenella.

BACKGROUND: The phylum Apicomplexa comprises a wide variety of parasites of significant medical and economic relevance. These parasites have extremely different host and tissue tropisms; for example Toxoplasma gondii can invade virtually any nucleated cell and infect almost all warm-blooded vertebrates, whereas Eimeria tenella infects only chickens and is restricted in its growth to epithelial cells of the caecum. Proteins released from the microneme secretory organelles (MICs) are critical for apicomplexan invasion of host cells and allow parasites to bind a diverse range of host cell oligosa…

Colibactin Contributes to the Hypervirulence of pks+ K1 CC23 Klebsiella pneumoniae in Mouse Meningitis Infections.

Klebsiella pneumoniae is the most common pathogen of community-acquired meningitis in Taiwan. However, the lack of a physiologically relevan … e which primarily infect the liver, the colibactin-producing (pks+) K1 CC23 strains had significant tropism toward the brain of BALB/c mice. We aimed in this study to develop a physiologically relevant meningitis model with the use of pks+ K1 CC23 K. pneumoniae. Acute meningitis was successfully induced in adult BALB/c male mice through orogastric, intran …

Using Adeno-associated Virus as a Tool to Study Retinal Barriers in Disease.

Müller cells are the principal glial cells of the retina. Their end-feet form the limits of the retina at the outer and inner limiting membr … s in disease states. Two AAV variants are useful for such study: AAV5 and ShH10. AAV5 has a natural tropism for photoreceptors but it cannot get across to the outer retina when administered into the vitreous when the ILM is intact (i.e., in wild-type retinas). ShH10 has a strong tropism towards glial cells and will selectively label Müller glia in both he …

Symptomatic adjacent segment pathology after posterior lumbar interbody fusion for adult low-grade isthmic spondylolisthesis.

The incidence of symptomatic adjacent segment pathology (ASP) after fusion surgery for adult low-grade isthmic spondylolisthesis (IS) has be … level, whole lumbar lordosis, segmental lordosis, preexisting laminar inclination angle, and facet tropism at the cranial fusion segment were analyzed to identify risk factors for symptomatic ASP. Four patients (ASP group) developed symptomatic ASP at the cranial segment adjacent to the fusion. There were no significant differences in age, sex, fusion le …

Equid herpesvirus type-1 exhibits neurotropism and neurovirulence in a mouse model.

Intranasal inoculation of equid herpesvirus type-1 (EHV-1) Brazilian strains A4/72 and A9/92 induced an acute and lethal infection in four d … rom their lungs at 3 dpi. These three EHV-1 strains showed distinct degrees of virulence and tissue tropism in mice. EHV-1 strains A4/72 and A9/92 exhibited a high degree of central nervous system tropism with neuroinvasion and neurovirulence. EHV-1 strain A3/97 was not neurovirulent despite being detected in the brains of infected BALB/c nude mice. These …

Q fever in pregnant goats: pathogenesis and excretion of Coxiella burnetii.

Coxiella burnetii is an intracellular bacterial pathogen that causes Q fever. Infected pregnant goats are a major source of human infection. … ats were successfully infected via the intranasal route. PCR and immunohistochemistry showed strong tropism of C. burnetii towards the placenta at two to four weeks after inoculation. Bacterial replication seemed to occur predominantly in the trophoblasts of the placenta and not in other organs of goats and kids. The amount of C. burnetii DNA in the organ …

Comparative analysis of replication characteristics of BoHV-1 subtypes in bovine respiratory and genital mucosa explants: a phylogenetic enlightenment.

In general, members of the Alphaherpesvirinae use the epithelium of the upper respiratory and/or genital tract as a preferential site for pr … at both mucosae could elucidate whether or not different BoHV-1 subtypes show differences in mucosa tropism. We established bovine respiratory and genital organ cultures with emphasis on maintenance of tissue morphology and viability during in vitro culture. In a next step, bovine respiratory and genital mucosa explants of the same animals were inoculated …

Sonography of pediatric small-bowel intussusception: differentiating surgical from nonsurgical cases.

Chlamydia trachomatis is an intracellular bacterium responsible for ocular, respiratory, and sexually transmitted diseases. The genome conta … ed that for six of nine pmp genes (not pmpA, pmpD, or pmpE), the serovars clustered based on tissue tropism. The most globally successful serovars, E and F, clustered distantly from the urogenital group for five pmp genes. These pmp genes may confer a biologic advantage that may facilitate infection and transmission for E and F. Surprisingly, serovar Da c …

Compartmentalization of HIV-1 in the central nervous system: role of the choroid plexus.

OBJECTIVES: To determine the genetic and phenotypic composition of HIV-1 found in the choroid plexus (CPx) and its relationship to virus in … nd phylogenetic comparisons were performed. RESULTS: CCR5-utilization was the most prevalent viral tropism found in all tissues, although spleen isolates also displayed CXCR4 usage. Viruses isolated from CPx consisted of both peripheral and brain-like virus, but were more related phenotypically and genetically to those found in the brain. Mutations found …

Narrowed host ranges do not constrain future host range expansion in RNA phage Φ6.

RNA viruses frequently shift between different host species and emerge on novel hosts. Part of this evolutionary process can involve specialization, when viruses adapt to increase their fitness on a particular host, often at the expense of their ability to infect other hosts. This trajectory has the potential to lead to extreme host narrowing, which excludes all other previously accessible hosts. The consequences of the evolutionary history of host specialization on a virus's future evolutionary potential are understudied. Using previously evolved specialized strains of model dsRNA bacteriopha

Capsular specificity in temperate phages of Klebsiella pneumoniae is driven by diverse receptor-binding enzymes.

Virulent bacteriophages infecting Klebsiella pneumoniae often show capsule-driven host tropism due to the presence of capsule-specific depolymerases. Yet for temperate phages the genetic and functional basis of such capsular specificity remains less well understood. Depolymerases appear unexpectedly rare in prophage genomes, raising unresolved questions about which prophage genes mediate capsular specificity, whether this apparent scarcity reflects biological or ecological differences versus annotation limitation, and whether prophage-encoded receptor-binding proteins (RBPs) are functionally a…