Treating acutely ill patients at home: Data from Singapore

INTRODUCTION@#Hospital-at-home programmes are well described in the literature but not in Asia. We describe a home-based inpatient substitutive care programme in Singapore, with clinical and patient-reported outcomes.@*METHODS@#We conducted a retrospective cohort study of patients admitted to a hospital-at-home programme from September 2020 to September 2021. Suitable patients, who otherwise required hospitalisation, were admitted to the programme. They were from inpatient wards, emergency department and community nursing teams in the western part of Singapore, where a multidisciplinary team provided hospital-level care at home. Electronic health record data were extracted from all patients admitted to the programme. Patient satisfaction surveys were conducted post-discharge.@*RESULTS@#A total of 108 patients enrolled. Mean age was 67.9 (standard deviation 16.7) years, and 46% were male. The main diagnoses were skin and soft tissue infections (35%), urinary tract infections (29%) and fluid overload (18%). Median length of stay was 4 (interquartile range 3-7) days. Seven patients were escalated back to the hospital, of whom 2 died after escalation. One patient died at home. There was 1 case of adverse drug reaction and 1 fall at home, and no cases of hospital-acquired infections. Patient satisfaction rates were high and 94% of contactable patients would choose to participate again.@*CONCLUSION@#Hospital-at-home programmes appear to be safe and feasible alternatives to inpatient care in Singapore. Further studies are warranted to compare clinical outcomes and cost to conventional inpatient care.

Room Temperature Isothermal Colorimetric Padlock Probe Rolling Circle Amplification for Viral RNA Detection

Seasonal flu and pandemics, which account for millions of infections and hundreds of thousands of deaths, require rapid and reliable detection mechanisms to implement preventive and therapeutic measures. Current detection methods of viral infections have limitations in speed, accuracy, accessibility, and usability. This project presents a novel, widely applicable viral diagnostic test that uses a modified version of rolling circle amplification (RCA) to be sensitive, specific, direct RNA targeted, colorimetric and operable at room temperature. We are specifically detecting the following high-impact viruses: SARS-CoV-2, Influenza A (H1N1pdm09), and Influenza B (Victoria Lineage), although our test can be adapted to any viral infection. Results using synthetic viral DNA and RNA sequences show that our diagnostic test takes approximately one hour, detects femtomolar concentrations of RNA strands, and differentiates between virus strains. We believe implementing our diagnostic test will provide faster responses to future viral-related outbreaks for quicker societal recovery.

The role of particle-to-cell interactions in dictating nanoparticle aided magnetophoretic separation of microalgal cells.

Successful application of a magnetophoretic separation technique for harvesting biological cells often relies on the need to tag the cells with magnetic nanoparticles. This study investigates the underlying principle behind the attachment of iron oxide nanoparticles (IONPs) onto microalgal cells, Chlorella sp. and Nannochloropsis sp., in both freshwater and seawater, by taking into account the contributions of various colloidal forces involved. The complex interplay between van der Waals (vdW), electrostatic (ES) and Lewis acid-base interactions (AB) in dictating IONP attachment was studied under the framework of extended Derjaguin-Landau-Verwey-Overbeek (XDLVO) analysis. Our results showed that ES interaction plays an important role in determining the net interaction between the Chlorella sp. cells and IONPs in freshwater, while the AB and vdW interactions play a more dominant role in dictating the net particle-to-cell interaction in high ionic strength media (≥100 mM NaCl), such as seawater. XDLVO predicted effective attachment between cells and surface functionalized IONPs (SF-IONPs) with an estimated secondary minimum of -3.12 kT in freshwater. This prediction is in accordance with the experimental observation in which 98.89% of cells can be magnetophoretically separated from freshwater with SF-IONPs. We have observed successful magnetophoretic separation of microalgal cells from freshwater and/or seawater for all the cases as long as XDLVO analysis predicts particle attachment. For both the conditions, no pH adjustment is required for particle-to-cell attachment.

Rapid magnetophoretic separation of microalgae.

Magnetic collection of the microalgae Chlorella sp. from culture media facilitated by low-gradient magnetophoretic separation is achieved in real time. A removal efficiency as high as 99% is accomplished by binding of iron oxide nanoparticles (NPs) to microalgal cells in the presence of the cationic polyelectrolyte poly(diallyldimethylammonium chloride) (PDDA) as a binder and subsequently subjecting the mixture to a NdFeB permanent magnet with surface magnetic field ≈6000 G and magnetic field gradient <80 T m(-1) . Surface functionalization of magnetic NPs with PDDA before exposure to Chlorella sp. is proven to be more effective in promoting higher magnetophoretic removal efficiency than the conventional procedure, in which premixing of microalgal cells with binder is carried out before the addition of NPs. Rodlike NPs are a superior candidate for enhancing the magnetophoretic separation compared to spherical NPs due to their stable magnetic moment that originates from shape anisotropy and the tendency to form large NP aggregates. Cell chaining is observed for nanorod-tagged Chlorella sp. which eventually fosters the formation of elongated cell clusters.