The etiologic agent of an outbreak of pneumonia in Wuhan, China, was identified as severe acute respiratory syndrome coronavirus 2 in January 2020. A patient in the United States was given a ...diagnosis of infection with this virus by the state of Washington and the US Centers for Disease Control and Prevention on January 20, 2020. We isolated virus from nasopharyngeal and oropharyngeal specimens from this patient and characterized the viral sequence, replication properties, and cell culture tropism. We found that the virus replicates to high titer in Vero-CCL81 cells and Vero E6 cells in the absence of trypsin. We also deposited the virus into 2 virus repositories, making it broadly available to the public health and research communities. We hope that open access to this reagent will expedite development of medical countermeasures.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, ODKLJ, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
We aerosolized severe acute respiratory syndrome coronavirus 2 and determined that its dynamic aerosol efficiency surpassed those of severe acute respiratory syndrome coronavirus and Middle East ...respiratory syndrome. Although we performed experiment only once across several laboratories, our findings suggest retained infectivity and virion integrity for up to 16 hours in respirable-sized aerosols.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, ODKLJ, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
With continued expansion of the coronavirus disease (COVID-19) pandemic, caused by severe acute respiratory syndrome 2 (SARS-CoV-2), both antiviral drugs as well as effective vaccines are desperately ...needed to treat patients at high risk of life-threatening disease. Here, we present in vitro evidence for significant inhibition of SARS-CoV-2 by oleandrin and a defined extract of N. oleander (designated as PBI-06150). Using Vero cells, we found that prophylactic (pre-infection) oleandrin (as either the pure compound or as the active principal ingredient in PBI-06150) administration at concentrations as low as 0.05 µg/ml exhibited potent antiviral activity against SARS-CoV-2, with an 800-fold reduction in virus production, and a 0.1 µg/ml concentration resulted in a greater than 3000-fold reduction in infectious virus production. The half maximal effective concentration (EC50) values were 11.98 ng/ml when virus output was measured at 24 h post-infection, and 7.07 ng/ml measured at 48 h post-infection. Therapeutic (post-infection) treatment up to 24 h after SARS-CoV-2 infection of Vero cells also reduced viral titers, with 0.1 µg/ml and 0.05 µg/ml concentrations causing greater than 100-fold reduction as measured at 48 h, and the 0.05 µg/ml concentration resulting in a 78-fold reduction. Concentrations of oleandrin up to 10 µg/ml were well tolerated in Vero cells. We also present in vivo evidence of the safety and efficacy of defined N. oleander extract (PBI-06150), which was administered to golden Syrian hamsters in a preparation containing as high as 130 µg/ml of oleandrin. In comparison to administration of control vehicle, PBI-06150 provided a statistically significant reduction of the viral titer in the nasal turbinates (nasal conchae). The potent prophylactic and therapeutic antiviral activities demonstrated here, together with initial evidence of its safety and efficacy in a relevant hamster model of COVID-19, support the further development of oleandrin and/or defined extracts containing this molecule for the treatment of SARS-CoV-2 and associated COVID-19 disease and potentially also for reduction of virus spread by persons diagnosed early after infection.
•Strong antiviral activity against “enveloped” viruses including coronaviruses.•Oleander shows significant antiviral effect against SARS-CoV-2 in Vero cells.•Oleandrin prevents as well as effectively treats SARS-CoV-2 infected Vero cells.•PBI-06150 was tested in vivo in an established hamster COVID-19 model.•Antiviral effect documented as reduction in tracheal tissue viral load.
The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike protein substitution D614G became dominant during the coronavirus disease 2019 (COVID-19) pandemic
. However, the effect of this ...variant on viral spread and vaccine efficacy remains to be defined. Here we engineered the spike D614G substitution in the USA-WA1/2020 SARS-CoV-2 strain, and found that it enhances viral replication in human lung epithelial cells and primary human airway tissues by increasing the infectivity and stability of virions. Hamsters infected with SARS-CoV-2 expressing spike(D614G) (G614 virus) produced higher infectious titres in nasal washes and the trachea, but not in the lungs, supporting clinical evidence showing that the mutation enhances viral loads in the upper respiratory tract of COVID-19 patients and may increase transmission. Sera from hamsters infected with D614 virus exhibit modestly higher neutralization titres against G614 virus than against D614 virus, suggesting that the mutation is unlikely to reduce the ability of vaccines in clinical trials to protect against COVID-19, and that therapeutic antibodies should be tested against the circulating G614 virus. Together with clinical findings, our work underscores the importance of this variant in viral spread and its implications for vaccine efficacy and antibody therapy.
While colorectal carcinoma is a common gastrointestinal cancer in adults, it is rare in pediatrics with an incidence of 1 : 1,000,000 and represents a fraction of neoplasms encountered in children. ...Malignant neoplasms represent a major cause of mortality in the pediatric age group. While presenting with weight loss, iron deficiency, rectal bleeding, abdominal pain, and change in bowel habits, or symptoms similar to acute appendicitis, the working diagnosis may be considered to be anorexia. This case illustrates the importance of considering colon cancer among other disease entities as a cause of unintentional weight loss in adolescents. While this is a rare occurrence in the pediatric population, significant unintentional weight loss with altered bowel habits should prompt a search for underlying malignancy—even in the absence of a positive family history or predisposing cancer syndromes.
•Live-attenuated V4020 VEEV vaccine virus contains rearranged structural genes.•V4020 includes attenuating mutations from TC83 vaccine engineered to prevent reversions.•Next-generation sequencing of ...V4020 did not detect reversion mutations.•V4020-vaccinated macaques were aviremic after stringent aerosol challenge with TrD VEEV.•V4020 is a promising experimental vaccine against VEEV.
Live-attenuated V4020 vaccine for Venezuelan equine encephalitis virus (VEEV) containing attenuating rearrangement of the virus structural genes was evaluated in a non-human primate model for immunogenicity and protective efficacy against aerosol challenge with wild-type VEEV. The genomic RNA of V4020 vaccine virus was encoded in the pMG4020 plasmid under control of the CMV promoter and contained the capsid gene downstream from the glycoprotein genes. It also included attenuating mutations from the VEE TC83 vaccine, with E2-120Arg substitution genetically engineered to prevent reversion mutations. The population of V4020 vaccine virus derived from pMG4020-transfected Vero cells was characterized by next generation sequencing (NGS) and indicated no detectable genetic reversions. Cynomolgus macaques were vaccinated with V4020 vaccine virus. After one or two vaccinations including by intramuscular route, high levels of virus-neutralizing antibodies were confirmed with no viremia or apparent adverse reactions to vaccinations. The protective effect of vaccination was evaluated using an aerosol challenge with VEEV. After challenge, macaques had no detectable viremia, demonstrating a protective effect of vaccination with live V4020 VEEV vaccine.
Viruses in the family
Rhabdoviridae
are ecologically very diverse, infecting mammals, birds, reptiles, fish, plants and a wide range of other terrestrial and aquatic invertebrates. The genus
...Sripuvirus
currently comprises five viruses that appear to circulate in transmission cycles involving reptiles and sandflies. Here, we report an analysis of the complete coding sequences of Cuiaba virus (CUIV), isolated from an amphibian (
Bufo marinus
) collected in Brazil, and Charleville virus (CHVV), isolated from sandflies (
Phlebotomus
sp.) and lizards (
Gehyra australis
), collected in Australia. CUIV and CHVV cluster phylogenetically with the sripuviruses in maximum likelihood trees generated from complete L protein (RdRp) sequences. They also share with sripuviruses unique features in genome organisation, including an additional gene (
U1
) between the matrix protein (
M
) gene and glycoprotein (
G
) gene, and an alternative long open reading frame near the start of the G ORF that encodes a predicted transmembrane protein. In view of their phylogenetic relationships, similar genome organisations and similar ecological characteristics, we propose the assignment of CUIV and CHVV as novel members of the genus
Sripuvirus
.
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