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Neural Stem Cells: What Happens When They Go Viral?

Viruses that infect the central nervous system (CNS) are associated with developmental abnormalities as well as neuropsychiatric and degenerative conditions. Many of these viruses such as Zika virus (ZIKV), cytomegalovirus (CMV), and herpes simplex virus (HSV) demonstrate tropism for neural stem cells (NSCs). NSCs are the multipotent progenitor cells of the brain that have the ability to form neurons, astrocytes, and oligodendrocytes. Viral infections often alter the function of NSCs, with profound impacts on the growth and repair of the brain. There are a wide spectrum of effects on NSCs, whi…

Cross-reactive antibodies binding to H4 hemagglutinin protect against a lethal H4N6 influenza virus challenge in the mouse model.

Influenza viruses of the H4 subtype are widespread in wild birds, circulate in domestic poultry, readily infect mammals, and tolerate the insertion of a polybasic cleavage site. In addition, serological evidence suggests that humans working with poultry are exposed to these viruses. While H4 viruses are not of immediate pandemic concern, there is a lack of knowledge regarding their antigenicity. In order to study viruses of the H4 subtype, we generated and characterized a panel of antibodies that bind a wide variety of H4 hemagglutinins from avian and swine isolates of both the Eurasian and No…

Почему вакцины против многих вирусных заболеваний человека до сих пор отсутствуют, что является исторической перспективой?

Количество новых и усовершенствованных вирусных вакцин, лицензированных людьми в последние годы, резко контрастирует с тем, что можно назвать золотой эпохой (1955-1990 годы), когда впервые появились вакцины против полиомиелита, кори, свинки, краснухи и гепатита В. Здесь мы пытаемся объяснить, почему вакцины, главным образом против вирусов, помимо вируса иммунодефицита человека и вируса гепатита С, по-прежнему недоступны. К их числу относятся герпесвирусы человека, не являющиеся вирусом варицелла-зостера, синтиальный дыхательный и большинство других респираторных, энтериальных и трансмиссивных

Совпадение в аннотации оригинала
The number of new and improved human viral vaccines licensed in recent years contrasts sharply with what could be termed the golden era (1955-1990) when vaccines against polio-, measles, mumps, rubella, and hepatitis B viruses first became available. Here, we attempt to explain why vaccines, mainly against viruses other than human immunodeficiency virus and …

Influenza Virus Infectivity Is Retained in Aerosols and Droplets Independent of Relative Humidity.

Pandemic and seasonal influenza viruses can be transmitted through aerosols and droplets, in which viruses must remain stable and infectious across a wide range of environmental conditions. Using humidity-controlled chambers, we studied the impact of relative humidity on the stability of 2009 pandemic influenza A(H1N1) virus in suspended aerosols and stationary droplets. Contrary to the prevailing paradigm that humidity modulates the stability of respiratory viruses in aerosols, we found that viruses supplemented with material from the apical surface of differentiated primary human airway epit…

[Sample Preparation and Imaging of Single Adenovirus Particle Using Atomic Force Microscopy in Liquid].

Atomic force microscopy (AFM), as a sophisticated imaging tool with nanoscale resolution, is widely used in virus research and the application of functional viral particles. To investigate single viruses by AFM in a physiologically relevant environment (liquid), an appropriate surface treatment to properly adhere the viruses to the substrate is essential. Here we discuss hydrophobic treated glass coverslips as a suitable substrate for the adhesion of single adenovirus particle (Adenovirus type 5 F35, Ad5F35) when studied with AFM in liquid. From the high resolution AFM images, the orientation …

Реагирование на стресс в инфекционных клетках: активация развернутого белка и автофагика.

Флавивирус — род вирусов РНК, который включает в себя множество известных на протяжении длительного времени человеческих, животных и зоонотических патогенов, таких, как вирус Денге, вирус желтой лихорадки, вирус Западного Нила или японский энцефалит, а также другие менее известные вирусы, представляющие потенциальную угрозу для здоровья человека и животных, такие как вирусы Усуту или Зика. Репликация флавируса основана на эндоплазмических ретикулумах. Реконструкция мембраны и накопление вирусных факторов вызывают эндоплазмическую ретикулумную нагрузку, которая приводит к активации реакции клет

Совпадение в аннотации оригинала
The Flavivirus is a genus of RNA viruses that includes multiple long known human, animal, and zoonotic pathogens such as Dengue virus, yellow fever virus, West Nile virus, or Japanese encephalitis virus, as well as other less known viruses that represent potential threats for human and animal health such as Usutu or Zika viruses. Flavivirus replication is ba…

Pathogens of house mice on arid Boullanger Island and subantarctic Macquarie Island, Australia.

Studies on island populations of house mice (Mus domesticus) and their viruses reveal insights into viral persistence in isolated communities. We surveyed the ectoparasites, endoparasites, and antiviral antibodies for 11 murine viruses and two bacteria of house mice inhabiting two islands off Australia. House mice on Boullanger Island were seropositive to two viruses, murine cytomegalovirus and epizootic diarrhea of infant mice. On subantarctic Macquarie Island, house mice were seropositive for five viruses: murine cytomegalovirus, lymphocytic choriomeningitis virus, mouse parvovirus, epizooti…

[Pertussis syndrome: study of 74 cases].

Pertussis syndrome controversy induced us to study 74 hospitalized patients, with pertussis cough and Bordetella sp isolation in 29, other bacteria in 24 and viruses in 21. The most frequently isolated bacteria in the patients with negative culture for bordetella were Haemophilus influenzae, Streptococcus pneumoniae and Branhamella catarrhalis. The viruses with highest incidence were respiratory syncitial viruses. The negative culture for bordetella, the lack of antibiotherapy previous to obtention of the sample (29/45 cases), the clinical differences and their different seasonal distribution …

In-vivo activity of antivirals against exotic RNA viral infections.

Infection of humans by viruses belonging to the families of Toga-, Bunya-, and Arenaviridae constitutes a major health problem worldwide and certain of the viruses have the potential to cause widespread epidemics. In the search for effective chemotherapy against these viruses several hundred nucleoside and nucleotide analogues have been screened for antiviral activity. Of the compounds tested, ribavirin, has been shown in laboratory animal models to have significant inhibitory effects against Rift Valley Fever virus, the bunyavirus Punta Toro, Hantaan virus and arenaviruses such as Pichinde, J…

The Emergence and Decennary Distribution of Clade 2.3.4.4 HPAI H5Nx.

Reassortment events among influenza viruses occur naturally and may lead to the development of new and different subtypes which often ignite the possibility of an influenza outbreak. Between 2008 and 2010, highly pathogenic avian influenza (HPAI) H5 of the N1 subtype from the A/goose/Guangdong/1/96-like (Gs/GD) lineage generated novel reassortants by introducing other neuraminidase (NA) subtypes reported to cause most outbreaks in poultry. With the extensive divergence of the H5 hemagglutinin (HA) sequences of documented viruses, the WHO/FAO/OIE H5 Evolutionary Working Group clustered these vi…

Zoonotic Influenza and Human Health-Part 1: Virology and Epidemiology of Zoonotic Influenzas.

PURPOSE OF REVIEW: Zoonotic influenza viruses are those that cross the animal-human barrier and can cause disease in humans, manifesting from minor respiratory illnesses to multiorgan dysfunction. They have also been implicated in the causation of deadly pandemics in recent history. The increasing incidence of infections caused by these viruses worldwide has necessitated focused attention to improve both diagnostic as well as treatment modalities. In this first part of a two-part review, we describe the structure of zoonotic influenza viruses, the relationship between mutation and pandemic cap…

Microcosm environment models for studying the stability of adenovirus and murine norovirus in water and sediment.

Microcosms are useful tools for understanding the survival and fate of enteric viruses in aquatic environments. This study set out to determine the stability of infectious enteric viruses in an aquatic environment using a laboratory scale microcosm. Sediment and overlaying water were collected from a lagoon and inoculated with known concentrations of recombinant adenovirus (AdV-GFP) and murine norovirus (MNV-1). Infectious particles of these viruses were measured using fluorescence microscopy (AdV-GFP) or the plaque assay method (MNV-1), over 85 days in two different conditions: under natural …

Fecal virome composition of migratory wild duck species.

The fecal virome comprises a complex diversity of eukaryotic viruses, phages and viruses that infect the host. However, little is known about the intestinal community of viruses that is present in wild waterfowl, and the structure of this community in wild ducks has not yet been studied. The fecal virome compositions of six species of wild dabbling ducks and one species of wild diving duck were thus analyzed. Fecal samples were collected directly from the rectums of 60 ducks donated by hunters. DNA and RNA virus particles were purified and sequenced using the MiSeq Illumina platform. The reads…

Disruption of the blood brain barrier is vital property of neurotropic viral infection of the central nervous system.

The blood brain barrier consisting of astrocytes, pericytes and brain microvascular endothelial cells plays a vital role in the pathogenesis of neurotropic viruses by controlling the access of circulating molecules, immune cells or viruses into the central nervous system (CNS). However, this barrier is not impenetrable and neuroviruses have evolved to disrupt and evade it. This review aims to describe the underlying entry mechanisms of several neuroviruses such as (Japanese encephalitis virus (JEV), West Nile virus (WNV), Zika virus (ZIKV), Nipah virus (NiV), Rabies virus (RABV), Herpes simple…

Chronic viral infections of the central nervous system: Aspects specific to multiple sclerosis.

The involvement of a viral infection in the physiopathology of multiple sclerosis has been said to cause certain viruses to target the central nervous system and induce neuroinflammation leading to cell dysfunction, as seen, for example, by demyelination or neuronal death. The most recent results of the literature have focused on the Herpes family viruses (HHV-6 and HHV-4/Epstein-Barr virus) and their possible role in the development of multiple sclerosis. Even if no virus has been identified so far as the multiple sclerosis etiological agent, our aim here is to show that some viruses may be r…

Transgenic mice carrying the human poliovirus receptor: new animal models for study of poliovirus neurovirulence.

Recombinant viruses between the virulent Mahoney and attenuated Sabin 1 strains of poliovirus type 1 were subjected to neurovirulence tests using a transgenic (Tg) mouse line, ICR-PVRTg1, that carried the human poliovirus receptor gene. The Tg mice were inoculated intracerebrally with these recombinant viruses and observed for clinical signs, histopathological lesions, and viral antigens as parameters of neurovirulence of the viruses. These parameters observed in the Tg mice were different for different inoculated viruses. Dose-dependent incidences of paralysis and of death were observed in th…

Long-Term Survival of Human Enteric Virus Surrogates (Murine Norovirus, Rhesus Rotavirus, and Porcine Sapovirus) in Bottled Drinking Water.

Enteric viruses are major causes of food- and waterborne diseases. Due to the limited cultivability of many human enteric viruses, surrogate viruses are commonly used to model their environmental persistence. This study aimed to evaluate the not-well-understood long-term survival of murine norovirus (MNV), rhesus rotavirus (RRV), and porcine sapovirus (PoSaV), used here as cultivable surrogate viruses for human enteric viruses, in bottled drinking water. Bottled water artificially inoculated with each virus was stored at 4 °C, 25 °C, and 37 °C for up to 365 days, and viral infectivity was quan…

Epidemiologic, clinical, and genetic characteristics of influenza C virus infections among outpatients and inpatients in Sendai, Japan from 2006 to 2020.

BACKGROUND: Influenza C virus is a pathogen that causes acute respiratory illness in children. The clinical information about this virus is limited because of the small number of isolated viruses compared to influenza A or B viruses. METHODS: A total of 60 influenza C viruses were isolated by clinical tests using cell culture methods conducted in one hospital and one clinic during the 15 years from 2006 to 2020. These 60 cases were retrospectively analyzed by comparing outpatients and inpatients. Moreover, isolated viruses were analyzed for genomic changes during the study period. RESULTS: A…

Characterization of Pipistrellus pygmaeus Bat Virome from Sweden.

Increasing amounts of data indicate that bats harbor a higher viral diversity relative to other mammalian orders, and they have been recognized as potential reservoirs for pathogenic viruses, such as the Hendra, Nipah, Marburg, and SARS-CoV viruses. Here, we present the first viral metagenomic analysis of Pipistrellus pygmaeus from Uppsala, Sweden. Total RNA was extracted from the saliva and feces of individual bats and analyzed using Illumina sequencing. The results identified sequences related to 51 different viral families, including vertebrate, invertebrate, and plant viruses. These viral …

Secondary substitutions in the hemagglutinin and neuraminidase genes associated with neuraminidase inhibitor resistance are rare in the Influenza Resistance Information Study (IRIS).

Amino acid substitutions in influenza virus neuraminidase (NA) that cause resistance to neuraminidase inhibitors (NAI) generally result in virus attenuation. However, influenza viruses may acquire secondary substitutions in the NA and hemagglutinin (HA) proteins that can restore viral fitness. To assess to which extent this happens, the emergence of NAI resistance substitutions and secondary - potentially compensatory - substitutions was quantified in influenza viruses of immunocompetent individuals included in the Influenza Resistance Information Study (IRIS; NCT00884117). Known resistance su…