Hydrogen peroxide vapour treatment inactivates norovirus but has limited effect on post-treatment viral RNA levels

ABSTRACT Background Novel SARS-CoV-2 Variants of Concern (VoC) pose a challenge to controlling the COVID-19 pandemic. Previous studies indicate that clinical samples collected from individuals infected with the Delta variant may contain higher levels of RNA than previous variants, but the relationship between viral RNA and infectious virus for individual variants is unknown. Methods We measured infectious viral titer (using a micro-focus forming assay) as well as total and subgenomic viral RNA levels (using RT-PCR) in a set of 165 clinical samples containing SARS-CoV-2 Alpha, Delta and Epsilon variants that were processed within two days of collection from the patient. Results We observed a high degree of variation in the relationship between viral titers and RNA levels. Despite the variability we observed for individual samples the overall infectivity differed among the three variants. Both Delta and Epsilon had significantly higher infectivity than Alpha, as measured by the number of infectious units per quantity of viral E gene RNA (6 and 4 times as much, p=0.0002 and 0.009 respectively) or subgenomic E RNA (11 and 7 times as much, p<0.0001 and 0.006 respectively). Conclusion In addition to higher viral RNA levels reported for the Delta variant, the infectivity (amount of replication competent virus per viral genome copy) may also be increased compared to Alpha. Measuring the relationship between live virus and viral RNA is an important step in assessing the infectivity of novel SARS-CoV-2 variants. An increase in the infectivity of the Delta variant may further explain increased spread and suggests a need for increased measures to prevent viral transmission.

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mTORC1 Restricts Hepatitis C Virus Replication Through ULK1-mediated Suppression of miR-122 and Facilitates Post-replication Events

10.1101/446757 ◽

2018 ◽

Author(s):

Manish Kumar Johri ◽

Hiren Vasantrai Lashkari ◽

Dhiviya Vedagiri ◽

Divya Gupta ◽

Krishnan Harinivas Harshan

Keyword(s):

Hepatitis C Virus ◽

Hepatitis C ◽

Viral Infection ◽

Virus Replication ◽

Viral Rna ◽

Hcv Rna ◽

Significant Drop ◽

Mechanistic Target Of Rapamycin ◽

Mtorc1 Activation ◽

Rna Levels

ABSTRACTMechanistic target of rapamycin (mTOR) is an important kinase that assimilates several upstream signals including viral infection and facilitates appropriate response by the cell through two unique complexes mTORC1 and mTORC2. Here, we demonstrate that mTORC1 is activated early during HCV infection as antiviral response. Pharmacological inhibition of mTORC1 promoted HCV replication as suggested by elevated levels of HCV (+) and (-) RNA strands. This was accompanied by significant drop in extracellular HCV RNA levels indicating defective post-replication stages. The increase in viral RNA levels failed to augment intracellular infectious virion levels, suggesting that mTORC1 inhibition is detrimental to post-replication steps. Lower infectivity of the supernatant confirmed this observation. Depletion of Raptor and ULK1 accurately reproduced these results suggesting that mTORC1 imparted these effects on HCV through mTORC1-ULK1 arm. Interestingly, ULK1 depletion resulted in increased levels of miR-122, a critical host factor for HCV replication, thus revealing a new mechanism of regulation by ULK1. The binary effect of mTORC1 on HCV replication and egress suggests that mTORC1-ULK1 could be critical in replication: egress balance. Interestingly we discover that ULK1 depletion did not interfere with autophagy in Huh7.5 cells and hence the effects on HCV replication and post-replication events are not resultant of involvement of autophagy. Our studies demonstrate an overall ULK1 mediated anti-HCV function of mTORC1 and identifies an ULK1-independent autophagy that allows HCV replication in spite of mTORC1 activation.

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Mesalamine Reduces Intestinal ACE2 Expression Without Modifying SARS-CoV-2 Infection or Disease Severity in Mice.

10.1101/2021.07.23.453393 ◽

2021 ◽

Author(s):

David M Alvarado ◽

Juhee Son ◽

Larissa B. Thackray ◽

Michael Diamond ◽

Siyuan Ding ◽

...

Keyword(s):

Viral Entry ◽

Post Infection ◽

Viral Rna ◽

Standardized Mortality Ratio ◽

Intestinal Loop ◽

Health Crisis ◽

Qrt Pcr ◽

Gi Symptoms ◽

Rna Levels

Introduction: Coronavirus Disease 2019 (COVID-19) is an ongoing public health crisis that has sickened or precipitated death in millions. The etiologic agent of COVID-19, Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), infects the intestinal epithelium, and can induce GI symptoms similar to the human inflammatory bowel diseases (IBD). An international surveillance epidemiology study (SECURE-IBD) reported that the standardized mortality ratio trends higher in IBD patients (1.5-1.8) and that mesalamine/sulfasalazine therapy correlates with poor outcome. The goal of our study was to experimentally address the relationship between mesalamine and SARS-CoV-2 entry, replication, and/or pathogenesis. Methods: Viral infection was performed with a chimeric vesicular stomatitis virus expressing SARS-CoV-2 spike protein and EGFP (VSV-SARS-CoV-2) and SARS-CoV-2 virus derived from an infectious cDNA clone of 2019n-CoV/USA_WA1/2020. Primary human ileal spheroids derived from healthy donors were grown as 3D spheroids or on 2D transwells. We assessed the effect of 10 mM mesalamine (Millipore Sigma) on viral RNA levels, as well as the expression of the SARS-CoV-2 receptor angiotensin II-converting enzyme 2 (ACE2), Transmembrane Serine Protease 2 (TMPRSS2), TMPRSS4, Cathepsin B (CTSB) and CTSL by qRT-PCR. 8-12 week old K18-ACE2 were treated orally with PBS or mesalamine at 200 mg/kg daily. Mice were inoculated intranasally with 1x10^3 FFU of SARS-CoV-2. Mice were weighed daily and viral titers were determined 7 days post infection (dpi) by qRT-PCR. For the intestinal viral entry model, VSV-SARS-CoV-2 was injected into a ligated intestinal loop of anesthetized K18-ACE2 mice and tissues were harvested 6 hours post-infection. Results: We found no change in viral RNA levels in human intestinal epithelial cells in response to mesalamine. Expression of ACE2 was reduced following mesalamine treatment in enteroids, while CTSL expression was increased. Mice receiving mesalamine lost weight at similar rates compared to mice receiving vehicle control. Mesalamine treatment did not change viral load in the lung, heart, or intestinal tissues harvested at 7 dpi. Pretreatment with mesalamine did not modulate intestinal entry of the chimeric VSV-SARS-CoV-2 in K18-ACE2 mice. Conclusions: Mesalamine did not alter viral entry, replication, or pathogenesis in vitro or in mouse models. Mesalamine treatment reduced expression of the viral receptor ACE2 while concurrently increasing CTSL expression in human ileum organoids.

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Catalytic oxidation with Al–Ce–Fe–PILC as a post-treatment system for coffee wet processing wastewater

Water Science & Technology ◽

10.2166/wst.2012.410 ◽

2012 ◽

Vol 66 (8) ◽

pp. 1663-1668 ◽

Cited By ~ 4

Author(s):

Nancy R. Sanabria ◽

Yury M. Peralta ◽

Mardelly K. Montañez ◽

Nelson Rodríguez-Valencia ◽

Rafael Molina ◽

...

Keyword(s):

Hydrogen Peroxide ◽

Catalytic Oxidation ◽

Batch Reactor ◽

Oxygen Demand ◽

Water Source ◽

Post Treatment ◽

Treatment System ◽

Total Phenolic ◽

Wet Processing ◽

High Conversion Rate

The effluent from the anaerobic biological treatment of coffee wet processing wastewater (CWPW) contains a non-biodegradable compound that must be treated before it is discharged into a water source. In this paper, the wet hydrogen peroxide catalytic oxidation (WHPCO) process using Al–Ce–Fe–PILC catalysts was researched as a post-treatment system for CWPW and tested in a semi-batch reactor at atmospheric pressure and 25 °C. The Al–Ce–Fe–PILC achieved a high conversion rate of total phenolic compounds (70%) and mineralization to CO2 (50%) after 5 h reaction time. The chemical oxygen demand (COD) of coffee processing wastewater after wet hydrogen peroxide catalytic oxidation was reduced in 66%. The combination of the two treatment methods, biological (developed by Cenicafé) and catalytic oxidation with Al-Ce–Fe–PILC, achieved a 97% reduction of COD in CWPW. Therefore, the WHPCO using Al–Ce–Fe–PILC catalysts is a viable alternative for the post-treatment of coffee processing wastewater.

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The Relationship between Simian Immunodeficiency Virus RNA Levels and the mRNA Levels of Alpha/Beta Interferons (IFN-α/β) and IFN-α/β-Inducible Mx in Lymphoid Tissues of Rhesus Macaques during Acute and Chronic Infection

Journal of Virology ◽

10.1128/jvi.76.16.8433-8445.2002 ◽

2002 ◽

Vol 76 (16) ◽

pp. 8433-8445 ◽

Cited By ~ 72

Author(s):

Kristina Abel ◽

Michelle J. Alegria-Hartman ◽

Kristina Rothaeusler ◽

Marta Marthas ◽

Christopher J. Miller

Keyword(s):

Virus Replication ◽

Acute Phase ◽

Rhesus Macaques ◽

Viral Rna ◽

Lymphoid Tissues ◽

Mrna Levels ◽

Immunodeficiency Virus ◽

Siv Infection ◽

Alpha Beta ◽

Rna Levels

ABSTRACT To define the role of alpha/beta interferons (IFN-α/β) in simian immunodeficiency virus (SIV) infection, IFN-α and IFN-β mRNA levels and mRNA levels of Mx, an antiviral effector molecule, were determined in lymphoid tissues of rhesus macaques infected with pathogenic SIV. IFN-α/β responses were induced during the acute phase and persisted in various lymphoid tissues throughout the chronic phase of infection. IFN-α/β responses were most consistent in tissues with high viral RNA levels; thus, IFN-α/β responses were not generally associated with effective control of SIV replication. IFN-α/β responses were differentially regulated in different lymphoid tissues and at different stages of infection. The most consistent IFN-α/β responses in acute and chronic SIV infection were observed in peripheral lymph nodes. In the spleen, only a transient increase in IFN-α/β mRNA levels during acute SIV infection was observed. Further, IFN-α and IFN-β mRNA levels showed a tissue-specific expression pattern during the chronic, but not the acute, phase of infection. In the acute phase of infection, SIV RNA levels in lymphoid tissues of rhesus macaques correlated with mRNA levels of both IFN-α and IFN-β, whereas during chronic SIV infection only increased IFN-α mRNA levels correlated with the level of virus replication in the same tissues. In lymphoid tissues of all SIV-infected monkeys, higher viral RNA levels were associated with increased Mx mRNA levels. We found no evidence that monkeys with increased Mx mRNA levels in lymphoid tissues had enhanced control of virus replication. In fact, Mx mRNA levels were associated with high viral RNA levels in lymphoid tissues of chronically infected animals.

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Improving the enzymatic hydrolysis of larch by coupling water pre-extraction with alkaline hydrogen peroxide post-treatment and adding enzyme cocktail

Bioresource Technology ◽

10.1016/j.biortech.2019.121322 ◽

2019 ◽

Vol 285 ◽

pp. 121322 ◽

Cited By ~ 5

Author(s):

Shuo Tang ◽

Wanying Liu ◽

Caoxing Huang ◽

Chenhuan Lai ◽

Yimin Fan ◽

...

Keyword(s):

Hydrogen Peroxide ◽

Enzymatic Hydrolysis ◽

Post Treatment ◽

Alkaline Hydrogen Peroxide ◽

Enzyme Cocktail ◽

Hydrolysis Of

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Removal of selected antibiotics and antiretroviral drugs during post‐treatment of municipal wastewater with UV, UV/chlorine and UV/hydrogen peroxide

Water and Environment Journal ◽

10.1111/wej.12612 ◽

2020 ◽

Vol 34 (4) ◽

pp. 692-703

Author(s):

Elijah Ngumba ◽

Anthony Gachanja ◽

Tuula Tuhkanen

Keyword(s):

Hydrogen Peroxide ◽

Municipal Wastewater ◽

Antiretroviral Drugs ◽

Post Treatment

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Combining UASB technology and advanced oxidation processes (AOPs) to treat food processing wastewaters

Water Science & Technology ◽

10.2166/wst.2002.0365 ◽

2002 ◽

Vol 45 (10) ◽

pp. 329-334 ◽

Cited By ~ 6

Author(s):

G.O. Sigge ◽

T.J. Britz ◽

P.C. Fourie ◽

C.A. Barnardt ◽

R. Strydom

Keyword(s):

Hydrogen Peroxide ◽

Food Processing ◽

Advanced Oxidation Processes ◽

Water System ◽

Post Treatment ◽

Significant Progress ◽

Oxidation Processes ◽

Legal Limit ◽

Direct Discharge ◽

Made In

UASB treatment of fruit cannery and winery effluents was shown to be feasible. However, the treated effluents still have residual COD levels well above the legal limit of 75 mg.L−1 for direct discharge to a water system and a form of post-treatment is necessary to reduce the COD further. Ozone and ozone/hydrogen peroxide were used in combination with a granular activated carbon contacting column to assess the effectiveness as a post-treatment option for the UASB treated fruit cannery and winery effluent. Colour reduction in the effluents ranged from 66 to 90% and COD reductions of 27–55% were achieved. The combination of ozone and hydrogen peroxide gave better results than ozonation alone. Significant progress was thus made in achieving the legal limit of 75 mg.L−1.

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