Bioaccumulation Pattern of the SARS-CoV-2 Spike Proteins in Pacific Oyster Tissues.

There is mounting evidence of the contamination of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in the sewage, surface water, and even marine environment. Various studies have confirmed that bivalve mollusks can bioaccumulate SARS-CoV-2 RNA to detectable levels. However, these results do not provide sufficient evidence for the presence of infectious viral particles. To verify whether oysters can bind the viral capsid and bioaccumulate the viral particles, Pacific oysters were artificially contaminated with the recombinant SARS-CoV-2 spike protein S1 subunit (rS1). The bioaccumulation pattern of the rS1 in different tissues was investigated by immunohistological assays. The results revealed that the rS1 was bioaccumulated predominately in the digestive diverticula. The rS1 was also present in the epithelium of the nondigestive tract tissues, including the gills, mantle, and heart. In addition, three potential binding ligands, including angiotensin-converting enzyme 2 (ACE 2)-like substances, A-type histo-blood group antigen (HBGA)-like substances, and oyster heat shock protein 70 (oHSP 70), were confirmed to bind rS1 and were distributed in tissues with various patterns. The colocalization analysis of rS1 and those potential ligands indicated that the distributions of rS1 are highly consistent with those of ACE 2-like substances and oHSP 70. Both ligands are distributed predominantly in the secretory absorptive cells of the digestive diverticula and may serve as the primary ligands to bind rS1. Therefore, oysters are capable of bioaccumulating the SARS-CoV-2 capsid readily by filter-feeding behavior assisted by specific binding ligands, especially in digestive diverticula. IMPORTANCE This is the first article to investigate the SARS-CoV-2 spike protein bioaccumulation pattern and mechanism in Pacific oysters by the histochemical method. Oysters can bioaccumulate SARS-CoV-2 capsid readily by filter-feeding behavior assisted by specific binding ligands. The new possible foodborne transmission route may change the epidemic prevention strategies and reveal some outbreaks that current conventional epidemic transmission routes cannot explain. This original and interdisciplinary paper advances a mechanistic understanding of the bioaccumulation of SARS-CoV-2 in oysters inhabiting contaminated surface water.

Operator Resource Planning in a Giga Fab during Covid-19 Restrictions

With the world facing a public health emergency due to the Coronavirus disease (COVID-19) in a global pandemic, this paper provides insight about how a simulation model was used to determine the impact of headcount variability during lockdown on fab performance. To create a robust simulation model, operator loading time was introduced as one of the input parameters. An existing and well validated Discrete Event Fab simulation model was extended with operator modelling, and was used to conduct case studies, evaluating the impact of different operator availability scenarios including work disruptions for several shifts within a week. The studies provide implications for operation to derive mitigation strategies, weighing the trade-off between cost demand and speed loss due to operator resources. © 2021 IEEE.

Lipid Lowering Effects of Herbal Supplements: A Review

As cardiovascular diseases are still a major cause of death in most countries, it is still relevant to look into treatment of such diseases. Dyslipidemia is one of the important identified risk factors for cardiovascular diseases. As this is largely driven by lifestyle and diet, it may be difficult to control it with lifestyle modifications alone. Currently, Statins remains to be the mainstay therapy for dyslipidemia but this is also met by problems within certain patient population. The drug may be contraindicated in certain patient groups;some patients tend to not respond to Statins;while certain patients may not tolerate the adverse events. This study looked into available literature on studies done on dyslipidemia using plant-based formulations using randomized clinical trial. Based on the review conducted, there are several plant-based formations with potential to be similar in efficacy to Statins. Some of the plants used are abundant or may be easily sourced. With the increasing popularity of food supplements or nutraceuticals, exploration on the potential of plant-based products is attractive. Despite the promising results of some studies, these will need further investigations and targeting a larger population size. Formulation options may need to be explored also focused on its stability. © RJPT All right reserved.

Marine mollusc extracts-Potential source of SARS-CoV-2 antivirals.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a novel human coronavirus and the causative agent of coronavirus disease 2019 (Covid-19). There is an urgent need for effective antivirals to treat current Covid-19 cases and protect those unable to be vaccinated against SARS-CoV-2. Marine molluscs live in an environment containing high virus densities (>107 virus particles per ml), and there are an estimated 100,000 species in the phylum Mollusca, demonstrating the success of their innate immune system. Mollusc-derived antivirals are yet to be used clinically despite the activity of many extracts, including against human viruses, being demonstrated in vitro. Hemolymph of the Pacific oyster (Crassostrea gigas) has in vitro antiviral activity against herpes simplex virus and human adenovirus, while antiviral action against SARS-CoV-2 has been proposed by in silico studies. Such evidence suggests that molluscs, and in particular C. gigas hemolymph, may represent a source of antivirals for human coronaviruses.