About 19,553 results

How deadly is monkeypox? What scientists know.
Nature Kozlov M

Sep 14th, 2022 - How deadly is monkeypox? What scientists know.|2022|Kozlov M,|mortality,virology,pathogenicity,

Identification of trypsin-degrading commensals in the large intestine.
Nature Li Y, Watanabe E et. al.

Sep 8th, 2022 - Increased levels of proteases, such as trypsin, in the distal intestine have been implicated in intestinal pathological conditions1-3. However, the players and mechanisms that underlie protease regulation in the intestinal lumen have remained unclear. Here we show that Paraprevotella strains isolated from the faecal microbiome of healthy human donors are potent trypsin-degrading commensals. Mec...

SARS-CoV-2 variant spike and accessory gene mutations alter pathogenesis.
Proceedings of the National Academy of Sciences of the Un... McGrath ME, Xue Y et. al.

Aug 31st, 2022 - The ongoing COVID-19 pandemic is a major public health crisis. Despite the development and deployment of vaccines against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the pandemic persists. The continued spread of the virus is largely driven by the emergence of viral variants, which can evade the current vaccines through mutations in the spike protein. Although these difference...

Risk of covid-19 related deaths for SARS-CoV-2 omicron (B.1.1.529) compared with delta ...
BMJ (Clinical Research Ed.); Ward IL, Bermingham C et. al.

Aug 3rd, 2022 - To assess the risk of covid-19 death after infection with omicron BA.1 compared with delta (B.1.617.2). Retrospective cohort study. England, United Kingdom, from 1 December 2021 to 30 December 2021. 1 035 149 people aged 18-100 years who tested positive for SARS-CoV-2 under the national surveillance programme and had an infection identified as omicron BA.1 or delta compatible. The main outcome ...

Secreted fungal virulence effector triggers allergic inflammation via TLR4.
Nature Dang EV, Lei S et. al.

Jul 28th, 2022 - Invasive fungal pathogens are major causes of human mortality and morbidity1,2. Although numerous secreted effector proteins that reprogram innate immunity to promote virulence have been identified in pathogenic bacteria, so far, there are no examples of analogous secreted effector proteins produced by human fungal pathogens. Cryptococcus neoformans, the most common cause of fungal meningitis a...

Omicron mutations enhance infectivity and reduce antibody neutralization of SARS-CoV-2 ...
Proceedings of the National Academy of Sciences of the Un... Syed AM, Ciling A et. al.

Jul 21st, 2022 - The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron variant contains extensive sequence changes relative to the earlier-arising B.1, B.1.1, and Delta SARS-CoV-2 variants that have unknown effects on viral infectivity and response to existing vaccines. Using SARS-CoV-2 virus-like particles (VLPs), we examined mutations in all four structural proteins and found that Omicron a...

Abrupt decreases in infectivity of SARS-CoV-2 in aerosols.
Proceedings of the National Academy of Sciences of the Un... Löndahl J, Alsved M

Jul 21st, 2022 - Abrupt decreases in infectivity of SARS-CoV-2 in aerosols.|2022|Löndahl J,Alsved M,|transmission,virology,growth & development,isolation & purification,pathogenicity,

The dynamics of SARS-CoV-2 infectivity with changes in aerosol microenvironment.
Proceedings of the National Academy of Sciences of the Un... Oswin HP, Haddrell AE et. al.

Jun 29th, 2022 - Understanding the factors that influence the airborne survival of viruses such as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in aerosols is important for identifying routes of transmission and the value of various mitigation strategies for preventing transmission. We present measurements of the stability of SARS-CoV-2 in aerosol droplets (∼5 to 10 µm equilibrated radius) over ...

The source of the Black Death in fourteenth-century central Eurasia.
Nature Spyrou MA, Musralina L et. al.

Jun 16th, 2022 - The origin of the medieval Black Death pandemic (AD 1346-1353) has been a topic of continuous investigation because of the pandemic's extensive demographic impact and long-lasting consequences1,2. Until now, the most debated archaeological evidence potentially associated with the pandemic's initiation derives from cemeteries located near Lake Issyk-Kul of modern-day Kyrgyzstan1,3-9. These sites...

Proteo-genetic analysis reveals clear hierarchy of ESX-1 secretion in Mycobacterium mar...
Proceedings of the National Academy of Sciences of the Un... Cronin RM, Ferrell MJ et. al.

Jun 8th, 2022 - The ESX-1 (ESAT-6-system-1) system and the protein substrates it transports are essential for mycobacterial pathogenesis. The precise ways that ESX-1 substrates contribute to virulence remains unknown. Several known ESX-1 substrates are also required for the secretion of other proteins. We used a proteo-genetic approach to construct high-resolution dependency relationships for the roles of indi...

Estrogen induces the expression of EBV lytic protein ZEBRA, a marker of poor prognosis ...
Cancer Science; Dochi H, Kondo S et. al.

May 29th, 2022 - Several epidemiological studies have suggested that Epstein-Barr virus (EBV) lytic infection is essential for the development of nasopharyngeal carcinoma (NPC), as the elevation of antibody titers against EBV lytic proteins is a common feature of NPC. Although ZEBRA protein is a key trigger for the initiation of lytic infection, whether its expression affects the prognosis and pathogenesis of N...

MERS-CoV endoribonuclease and accessory proteins jointly evade host innate immunity dur...
Proceedings of the National Academy of Sciences of the Un... Comar CE, Otter CJ et. al.

May 21st, 2022 - Middle East respiratory syndrome coronavirus (MERS-CoV) emerged into humans in 2012, causing highly lethal respiratory disease. The severity of disease may be, in part, because MERS-CoV is adept at antagonizing early innate immune pathways—interferon (IFN) production and signaling, protein kinase R (PKR), and oligoadenylate synthetase/ribonuclease L (OAS/RNase L)—activated in response to viral ...

Infectivity versus fatality of SARS-CoV-2 mutations and influenza.
International Journal of Infectious Diseases : IJID : Off... Xue L, Jing S et. al.

May 19th, 2022 - Because of the spread of the Omicron variant, many countries have experienced COVID-19 case numbers unseen since the start of the pandemic. We aimed to compare the epidemiological characteristics of Omicron with previous variants and different strains of influenza to provide context for public health responses. We developed transmission models for SARS-CoV-2 variants and influenza, in which tra...

Characterization and antiviral susceptibility of SARS-CoV-2 Omicron BA.2.
Nature Uraki R, Kiso M et. al.

May 17th, 2022 - The recent emergence of SARS-CoV-2 Omicron (B.1.1.529 lineage) variants possessing numerous mutations has raised concerns of decreased effectiveness of current vaccines, therapeutic monoclonal antibodies and antiviral drugs for COVID-19 against these variants1,2. The original Omicron lineage, BA.1, prevailed in many countries, but more recently, BA.2 has become dominant in at least 68 countries...

Inflammasome activation in infected macrophages drives COVID-19 pathology.
Nature Sefik E, Qu R et. al.

Apr 29th, 2022 - Severe COVID-19 is characterized by persistent lung inflammation, inflammatory cytokine production, viral RNA and a sustained interferon (IFN) response, all of which are recapitulated and required for pathology in the SARS-CoV-2-infected MISTRG6-hACE2 humanized mouse model of COVID-19, which has a human immune system1-20. Blocking either viral replication with remdesivir21-23 or the downstream ...

Pathological Characteristics of Echovirus 30 Infection in a Mouse Model.
Journal of Virology; Li J, Zhang G et. al.

Apr 15th, 2022 - Echovirus 30 (E30), a member of species B enterovirus, is associated with outbreaks of aseptic meningitis and has become a global health emergency. However, the pathogenesis of E30 remains poorly understood due to the lack of appropriate animal models. In this study, we established a mouse infection model to explore the pathogenicity of E30. The 2-day-old IFNAR-/- mice infected with E30 strain ...

Two Conserved Phenylalanine Residues in the E1 Fusion Loop of Alphaviruses Are Essentia...
Journal of Virology; Lucas CJ, Davenport BJ et. al.

Apr 14th, 2022 - Alphaviruses infect cells by a low pH-dependent fusion reaction between viral and host cell membranes that is mediated by the viral E1 glycoprotein. Most reported alphavirus E1 sequences include two phenylalanines (F87 and F95) in the fusion loop, yet the role of these residues in viral infectivity remains to be defined. Following introduction of wild type (WT), E1-F87A, and E1-F95A chikungunya...

Histopathology of persistent long COVID toe: A case report.
Journal of Cutaneous Pathology; Nirenberg MS, Requena L et. al.

Apr 3rd, 2022 - During the 2020 coronavirus (SARS-CoV-2) pandemic, several cutaneous lesions were identified, including pseudo-chilblain, vesicular, urticarial, maculopapular, and livedo/necrosis. A 59-year-old obese man with probable COVID-19 developed painful cyanosis with histopathologic capillary thrombosis of toes, and the cyanosis persisted for nearly 22 months. Shortly after initial exposure to family m...

Defining the risk of SARS-CoV-2 variants on immune protection.
Nature DeGrace MM, Ghedin E et. al.

Apr 2nd, 2022 - The global emergence of many severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants jeopardizes the protective antiviral immunity induced after infection or vaccination. To address the public health threat caused by the increasing SARS-CoV-2 genomic diversity, the National Institute of Allergy and Infectious Diseases within the National Institutes of Health established the SARS-C...

Distinctive Roles of Furin and TMPRSS2 in SARS-CoV-2 Infectivity.
Journal of Virology; Essalmani R, Jain J et. al.

Mar 29th, 2022 - The spike protein (S) of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) directs infection of the lungs and other tissues following its binding to the angiotensin-converting enzyme 2 (ACE2) receptor. For effective infection, the S protein is cleaved at two sites: S1/S2 and S2'. The "priming" of the surface S protein at S1/S2 (PRRAR685↓) [the underlined basic amino acids refer to cr...