The Cellular Characterization of SARS-CoV-2 Spike Protein in Virus-Infected Cells Using the Receptor Binding Domain Binding Specific Human Monoclonal Antibodies.

A human monoclonal antibody panel (PD4, PD5, PD7, SC23, and SC29) was isolated from the B cells of convalescent patients and used to examine the S protein in SARS-CoV-2-infected cells. While all five antibodies bound conformational-specific epitopes within SARS-CoV-2 spike (S) protein, only PD5, PD7, and SC23 were able to bind to the receptor binding domain (RBD). Immunofluorescence microscopy was used to examine the S protein RBD in cells infected with the Singapore isolates SARS-CoV-2/0334 and SARS-CoV-2/1302.

Lack of viable severe acute respiratory coronavirus virus 2 (SARS-CoV-2) among PCR-positive air samples from hospital rooms and community isolation facilities.

Background: Understanding the extent of aerosol-based transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is important for tailoring interventions for control of the coronavirus disease 2019 (COVID-19) pandemic. Multiple studies have reported the detection of SARS-CoV-2 nucleic acid in air samples, but only one study has successfully recovered viable virus, although it is limited by its small sample size.

Objective: We aimed to determine the extent of shedding of viable SARS-CoV-2 in respiratory aerosols from COVID-19 patients.

Environmental contamination in a coronavirus disease 2019 (COVID-19) intensive care unit-What is the risk?

Background: The risk of environmental contamination by severe acute respiratory coronavirus virus 2 (SARS-CoV-2) in the intensive care unit (ICU) is unclear. We evaluated the extent of environmental contamination in the ICU and correlated this with patient and disease factors, including the impact of different ventilatory modalities.

Methods: In this observational study, surface environmental samples collected from ICU patient rooms and common areas were tested for SARS-CoV-2 by polymerase chain reaction (PCR).

An unusual outbreak of rotavirus G8P[8] gastroenteritis in adults in an urban community, Singapore, 2016.

Background: An outbreak of gastroenteritis (GE) occurred in community-dwelling adults in the Central Region of urban Singapore, in May 2016.

Objectives: To investigate the cause of the outbreak.

Study Design: We conducted a case-cohort study on GE patients linked to the outbreak who presented to the emergency department of a tertiary-care hospital near the outbreak area, from 18 May to 11 June 2016.

Emergence of norovirus GI.2 outbreaks in military camps in Singapore.

Background: Simultaneous acute gastroenteritis (AGE) outbreaks occurred at two military camps. This study details the epidemiological findings, explores possible origins, and discusses preventive measures.

Methods: Investigations included attack rate surveys, symptom surveys, hygiene inspections, and the testing of water, food, and stool samples.

Sleeping Beauty mutagenesis in a mouse medulloblastoma model defines networks that discriminate between human molecular subgroups.

The Sleeping Beauty (SB) transposon mutagenesis screen is a powerful tool to facilitate the discovery of cancer genes that drive tumorigenesis in mouse models. In this study, we sought to identify genes that functionally cooperate with sonic hedgehog signaling to initiate medulloblastoma (MB), a tumor of the cerebellum. By combining SB mutagenesis with Patched1 heterozygous mice (Ptch1(lacZ/+)), we observed an increased frequency of MB and decreased tumor-free survival compared with Ptch1(lacZ/+) controls.

Antibiotic susceptibility of mammalian mitochondrial translation.

All medically useful antibiotics should have the potential to distinguish between target microbes (bacteria) and host cells. Although many antibiotics that target bacterial protein synthesis show little effect on the translation machinery of the eukaryotic cytoplasm, it is unclear whether these antibiotics target or not the mitochondrial translation machinery. We employed an in vitro translation system from bovine mitochondria, which consists of mitochondrial ribosomes and mitochondrial elongation factors, to estimate the effect of antibiotics on mitichondrial protein synthesis.