scholarly journals Rapid, dose-dependent and efficient inactivation of surface dried SARS-CoV-2 by 254 nm UV-C irradiation

2021 ◽  
Vol 26 (42) ◽  
Author(s):  
Natalia Ruetalo ◽  
Ramona Businger ◽  
Michael Schindler
Keyword(s):  
High Titre ◽  
Short Exposure ◽  
Low Doses ◽  
Dose Dependency ◽  
Viral Titre ◽  
Log Reduction ◽  
Order Of Magnitude ◽  
The Relationship ◽  
Uv C ◽  
Dose Dependent

Background: The COVID-19 pandemic urges for cheap, reliable, and rapid technologies for disinfection and decontamination. One frequently proposed method is ultraviolet (UV)-C irradiation. UV-C doses necessary to achieve inactivation of high-titre SARS-CoV-2 are poorly defined. Aim: We investigated whether short exposure of SARS-CoV-2 to UV-C irradiation sufficiently reduces viral infectivity and doses necessary to achieve an at least 6-log reduction in viral titres. Methods: Using a box and two handheld systems designed to decontaminate objects and surfaces, we evaluated the efficacy of 254 nm UV-C treatment to inactivate surface dried high-titre SARS-CoV-2. Results: Drying for 2 hours did not have a major impact on the infectivity of SARS-CoV-2, indicating that exhaled virus in droplets or aerosols stays infectious on surfaces for at least a certain amount of time. Short exposure of high titre surface dried virus (3–5*10^6 IU/ml) with UV-C light (16 mJ/cm2) resulted in a total inactivation of SARS-CoV-2. Dose-dependency experiments revealed that 3.5 mJ/cm2 were still effective to achieve a > 6-log reduction in viral titres, whereas 1.75 mJ/cm2 lowered infectivity only by one order of magnitude. Conclusions: SARS-CoV-2 is rapidly inactivated by relatively low doses of UV-C irradiation and the relationship between UV-C dose and log-viral titre reduction of surface residing SARS-CoV-2 is nonlinear. Our findings emphasize that it is necessary to assure sufficient and complete exposure of all relevant areas by integrated UV-C doses of at least 3.5 mJ/cm2 at 254 nm. Altogether, UV-C treatment is an effective non-chemical option to decontaminate surfaces from high-titre infectious SARS-CoV-2.

scholarly journals Mitigation of Airborne PRRSV Transmission with UV Light Treatment: Proof-of-concept

2021 ◽  
Author(s):  
Peiyang Li ◽  
Jacek A. Koziel ◽  
Jeffrey J. Zimmerman ◽  
Jianqiang Zhang ◽  
Ting-Yu Cheng ◽  
...  
Keyword(s):  
Uv Light ◽  
Pilot Scale ◽  
Respiratory Syndrome Virus ◽  
Two Stage ◽  
Short Treatment ◽  
Log Reduction ◽  
Stage Models ◽  
One Stage ◽  
Order Of Magnitude ◽  
Uv C

Proper treatment of infectious air could potentially mitigate the spread of airborne viruses such as porcine reproductive and respiratory syndrome virus (PRRSV). The objective of this research is to test the effectiveness of ultraviolet (UV) in inactivating aerosolized PRRSV, specifically, four UV lamps, UV-A (365 nm, both fluorescent and LED-based), "excimer" UV-C (222 nm), and germicidal UV-C (254 nm), were tested. The two UV-C lamps effectively irradiated fast-moving PRRSV aerosols with short treatment times (<2 s). One-stage and two-stage UV inactivation models estimated the UV doses needed for target percentage (%) reductions on PRRSV titer. UV-C (254 nm) dose needed for 3-log (99.9%) reduction was 0.521 and 0.0943 mJ/cm2, respectively, based on one-stage and two-stage models. An order of magnitude lower UV-C (222 nm) doses were needed for a 3-log reduction, i.e., 0.0882 and 0.048 mJ/cm2, based on one-stage and two-stage models, respectively. However, the cost of 222-nm excimer lamps is still economically prohibitive for scaling-up trials. The UV-A (365 nm) lamps could not reduce PRRSV titers for tested doses up to 4.11 mJ/cm2. Pilot-scale or farm-scale testing of UV-C on PRRSV aerosols simulating barn ventilation rates are recommended based on its effectiveness and reasonable costs comparable to HEPA filtration.

scholarly journals Rapid and efficient inactivation of surface dried SARS-CoV-2 by UV-C irradiation

2020 ◽  
Author(s):  
Natalia Ruetalo ◽  
Ramona Businger ◽  
Michael Schindler
Keyword(s):  
High Titer ◽  
Short Exposure ◽  
Low Doses ◽  
Total Reduction ◽  
Uv C

AbstractThe SARS-CoV-2 pandemic urges for cheap, reliable and rapid technologies for disinfection and decontamination. We here evaluated the efficiency of UV-C irradiation to inactivate surface dried SARS-CoV-2. Drying for two hours did not have a major impact on the infectivity of SARS-CoV-2, indicating that exhaled virus in droplets or aerosols stays infectious on surfaces at least for a certain amount of time. Strikingly, short exposure of high titer surface dried virus (3*10^6 IU/ml) with UV-C light (16 mJ/cm2) resulted in a total reduction of SARS-CoV-2 infectivity. Together, our results demonstrate that SARS-CoV-2 is rapidly inactivated by relatively low doses of UV-C irradiation. Hence, UV-C treatment is an effective non-chemical possibility to decontaminate surfaces from high-titer infectious SARS-CoV-2.

scholarly journals Mitigation of Airborne PRRSV Transmission with UV Light Treatment: Proof-of-Concept

Agriculture ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 259
Author(s):  
Peiyang Li ◽  
Jacek A. Koziel ◽  
Jeffrey J. Zimmerman ◽  
Jianqiang Zhang ◽  
Ting-Yu Cheng ◽  
...  
Keyword(s):  
Uv Light ◽  
Pilot Scale ◽  
Respiratory Syndrome Virus ◽  
Two Stage ◽  
Short Treatment ◽  
Log Reduction ◽  
Stage Models ◽  
One Stage ◽  
Order Of Magnitude ◽  
Uv C

Proper treatment of infectious air could potentially mitigate the spread of airborne viruses such as porcine reproductive and respiratory syndrome virus (PRRSV). The objective of this research is to test the effectiveness of ultraviolet (UV) in inactivating aerosolized PRRSV, specifically, four UV lamps, UV-A (365 nm, both fluorescent and LED-based), “excimer” UV-C (222 nm), and germicidal UV-C (254 nm), were tested. The two UV-C lamps effectively irradiated fast-moving PRRSV aerosols with short treatment times (<2 s). One-stage and two-stage UV inactivation models estimated the UV doses needed for target percentage (%) reductions on PRRSV titer. UV-C (254 nm) dose needed for 3-log (99.9%) reduction was 0.521 and 0.0943 mJ/cm2, respectively, based on one-stage and two-stage models. An order of magnitude lower UV-C (222 nm) doses were needed for a 3-log reduction, i.e., 0.0882 and 0.048 mJ/cm2, based on one-stage and two-stage models, respectively. However, the cost of 222 nm excimer lamps is still economically prohibitive for scaling-up trials. The UV-A (365 nm) lamps could not reduce PRRSV titers for tested doses up to 4.11 mJ/cm2. Pilot-scale or farm-scale testing of UV-C on PRRSV aerosols simulating barn ventilation rates are recommended based on its effectiveness and reasonable costs comparable to HEPA filtration.

Involvement of 5-Hydroxytryptamine in Platelet Aggregation In Vivo in Rats and Guinea Pigs

1989 ◽  
Vol 61 (03) ◽  
pp. 463-467 ◽  
Author(s):  
G M Smith
Keyword(s):  
Platelet Count ◽  
Guinea Pigs ◽  
Platelet Adhesion ◽  
Adenosine Diphosphate ◽  
Rate Of Return ◽  
Low Doses ◽  
Dose Dependent ◽  
Higher Doses ◽  
Rat Platelets

SummaryIn this study, 5-hydroxytryptamine (5-HT) caused a dose- dependent fall in the circulating platelet count suggesting that 5-HT receptors are activated in rat platelets to cause platelet adhesion and aggregation. When low doses of adenosine diphosphate (ADP) were simultaneously injected with 5-HT, there was a significant potentiation of the responses to ADR Ketanserin significantly reduced the potentiated responses. When higher doses of ADP were infused with bolus injections of 5-HT there was no potentiation and ketanserin did not reduce these responses. Ketanserin did not inhibit the collagen-induced fall in circulating platelet count, but did significantly increase the rate of return to the basal platelet count compared with control. 5-HT did not cause a fall in platelet count in guinea-pigs

The Effect of Adrenaline Infusions on Blood Coagulation in Normal and Haemophilia B Dogs

1966 ◽  
Vol 15 (03/04) ◽  
pp. 349-364 ◽  
Author(s):  
A.H Özge ◽  
H.C Rowsell ◽  
H.G Downie ◽  
J.F Mustard
Keyword(s):  
Body Weight ◽  
Factor Viii ◽  
Factor Ix ◽  
Clotting Factor ◽  
Blood Ph ◽  
Order Of Magnitude ◽  
Dose Dependent ◽  
Generation Test ◽  
Plasma Activity

SummaryThe addition of trace amounts of adrenaline to whole blood in plasma in vitro increased factor VIII, factor IX and whole plasma activity in the thromboplastin generation test. This was dose dependent.Adrenaline infusions less than 22 (μg/kg body weight in normal dogs accelerated clotting, increased factor IX, factor VIII and whole plasma activity in the thromboplastin generation test and caused a fall in blood pH. In a factor IX deficient dog, there was no increase in factor IX activity. After adrenaline infusions, however, the other changes occurred and were of the same order of magnitude as in the normal. Adrenaline in doses greater than 22 μg/kg body weight did not produce as great an effect on clotting in normal or factor IX deficient dogs. The platelet count in the peripheral blood was increased following the infusion of all doses of adrenaline. These observations suggest that the accelerating effect of adrenaline on clotting is not mediated through increase in activity of a specific clotting factor.

Pound Wise and Penny Foolish? Weight Loss and The Dynamics of Health Care Spending

2011 ◽  
Vol 14 (2) ◽  
Author(s):  
Thomas G Koch
Keyword(s):  
Weight Loss ◽  
Cost Savings ◽  
Cost Effective ◽  
Economic Consequences ◽  
Health Care Spending ◽  
Order Of Magnitude ◽  
Dynamic Measures ◽  
The Cost ◽  
The Impact ◽  
The Relationship

Current estimates of obesity costs ignore the impact of future weight loss and gain, and may either over or underestimate economic consequences of weight loss. In light of this, I construct static and dynamic measures of medical costs associated with body mass index (BMI), to be balanced against the cost of one-time interventions. This study finds that ignoring the implications of weight loss and gain over time overstates the medical-cost savings of such interventions by an order of magnitude. When the relationship between spending and age is allowed to vary, weight-loss attempts appear to be cost-effective starting and ending with middle age. Some interventions recently proven to decrease weight may also be cost-effective.

scholarly journals Excessive Pressure in Multichambered Cuffs Used for Sequential Compression Therapy

2002 ◽  
Vol 82 (10) ◽  
pp. 1000-1008 ◽  
Author(s):  
Patrick Segers ◽  
Jean-Paul Belgrado ◽  
Andre Leduc ◽  
Olivier Leduc ◽  
Pascal Verdonck
Keyword(s):  
Time Course ◽  
Compression Therapy ◽  
Lymphatic Drainage ◽  
Chamber Pressure ◽  
Excessive Pressure ◽  
Ellipsoidal Model ◽  
Order Of Magnitude ◽  
Pneumatic Compression Devices ◽  
Target Pressure ◽  
The Relationship

Abstract Background and Purpose. Pneumatic compression devices, used as part of the therapeutic strategy for lymphatic drainage, often have cuffs with multiple chambers that are inflated sequentially. The purpose of this study was to investigate (1) the relationship between cuff chamber pressure (Pchamber) and the pressure on the cuff-skin interface (Pinterface) and (2) the mechanical interaction of cuff chambers and consequences for device control. Subjects and Methods. In this study, we used 3 cylindrical (60-, 80-, and 100-mm-diameter) model limbs and 1 ellipsoidal model of the arm to test a commercially available pressure controller using “target pressures,” indicated by the controller, of 30, 60, 80, and 100 mm Hg. We studied the time course of Pchamber and Pinterface during the inflation sequence and the effect of local curvature on Pinterface. Results. Our data indicated that, overall, Pinterface is of the same order of magnitude as Pchamber. There was some effect of model diameter and shape, with the smaller curvatures yielding the highest Pinterface. Cuff chamber interaction led to Pchamber and Pinterface values in the most distal (first inflated) chamber that were up to 80% higher than the target pressure. For the 80-mm cylindrical model, for instance, pressure in this chamber reached 54, 98, 121, and 141 mm Hg, respectively, instead of the 30, 60, 80, and 100 mm Hg indicated by the controller. Discussion and Conclusion. The discrepancy between the target pressure, indicated by the controller, and the pressure measured inside the cuff chambers undermines the therapeutic control and efficacy of the pneumatic compression devices. Because the measured pressures were far beyond the pressure level indicated by the controller, it is recommended that pneumatic compression devices be used at much lower target pressures (&lt;30 mm Hg) than those applied in clinical practice.

Even low doses of steroids increase the risk of cardiovascular disease in people with inflammatory diseases

BMJ ◽  
2021 ◽  
pp. n2599
Author(s):  
Helen Saul ◽  
Deniz Gursul
Keyword(s):  
Cardiovascular Disease ◽  
Cohort Study ◽  
Inflammatory Diseases ◽  
Population Based ◽  
Low Doses ◽  
Cardiovascular Risks ◽  
Oral Glucocorticoid ◽  
Link Type ◽  
Immune Mediated ◽  
Dose Dependent

The study Pujades-Rodríguez M, Morgan AW, Cubbon RM, Wu J. Dose-dependent oral glucocorticoid cardiovascular risks in people with immune-mediated inflammatory diseases: a population-based cohort study. PLoS Med 2020;17:e1003432. To read the full NIHR Alert, go to: https://evidence.nihr.ac.uk/alert/low-doses-steroids-increase-cardiovascular-risks-in-inflammatory-diseases/

Abstract 6277: Predictive Value of Estimated Glomerular Filtration Rate for Cardiovascular Events: The Treating to New Targets Study

Circulation ◽  
2008 ◽  
Vol 118 (suppl_18) ◽  
Author(s):  
James Shepherd ◽  
Chuan-Chuan Wun ◽  
Daniel J Wilson ◽  
Andrea L Zuckerman
Keyword(s):  
Renal Function ◽  
Glomerular Filtration Rate ◽  
Glomerular Filtration ◽  
Cardiovascular Events ◽  
Filtration Rate ◽  
Estimated Glomerular Filtration Rate ◽  
Lipid Lowering ◽  
Final Visit ◽  
The Relationship ◽  
Dose Dependent

We previously demonstrated a dose-dependent improvement in renal function and reduction in cardiovascular risk in TNT with intensive lipid lowering with atorvastatin (ATV) 80 mg vs 10 mg. This post hoc analysis examines the relationship between the observed improvement in estimated glomerular filtration rate (eGFR) and reduction of major cardiovascular events (MCVE). After 8 weeks open-label therapy with ATV 10 mg, 10,001 patients with CHD were randomized to double-blind therapy with either ATV 10 or 80 mg. Patients were followed for a median of 4.9 years for the occurrence of MCVEs (CHD death, nonfatal MI, and stroke). The relationship between change from baseline eGFR (using the MDRD equation) at the final visit prior to a MCVE and the risk of MCVE was assessed using a Cox proportional hazards model adjusting for baseline eGFR and other baseline characteristics. Of 9656 patients with complete renal data, 156 had a MCVE before follow-up eGFR assessment and were excluded. In the remaining 9500 patients, mean baseline eGFR was 65.3 mL/min/1.73 m 2 and mean change from baseline was 4.3 mL/min/1.73 m 2 . This represented a reduction in the risk of MCVE of 2.7% per mL increase in eGFR (HR 0.973, 95% CI 0.967– 0.980, P <0.0001). This association remained significant in patients with eGFR <60 and those with eGFR ≥60 mL/min/1.73 m 2 at baseline, with no significant interaction between eGFR change and baseline renal status ( P =0.98). A 5 mL/min on-treatment improvement in eGFR was associated with a 12.6% reduction in MCVE, while a 5 mL/min reduction was associated with a 14.4% increase in MCVE. Mean change from baseline eGFR was 3.5 mL/min/1.73 m 2 with ATV 10 mg and 5.2 mL/min/1.73 m 2 with ATV 80 mg, representing significant 9.3% and 12.4% reductions in risk, respectively. Analysis of interaction between treatment and eGFR change for prediction of MCVE demonstrated a stronger association between eGFR change and MCVE in the ATV 80 mg treatment group ( P =0.011). Improvement in eGFR was highly associated with a reduction in MCVE, irrespective of baseline renal function. This relationship was dose dependent. Improvement in eGFR may be a biomarker for the response to atorvastatin, and for the stabilization of atherosclerotic cardiovascular disease.

scholarly journals Kahweol Exerts Skin Moisturizing Activities by Upregulating STAT1 Activity

2021 ◽  
Vol 22 (16) ◽  
pp. 8864
Author(s):  
Hongxi Chen ◽  
Mohammad Amjad Hossain ◽  
Jong-Hoon Kim ◽  
Jae Youl Cho
Keyword(s):  
Proper Time ◽  
Radical Scavenging ◽  
Polymerase Chain Reaction Analysis ◽  
Luciferase Assay ◽  
Dependent Manner ◽  
Diphenyltetrazolium Bromide ◽  
Polymerase Chain ◽  
Radical Scavenging Ability ◽  
The Relationship ◽  
Dose Dependent

Kahweol is a diterpene present in coffee. Until now, several studies have shown that kahweol has anti-inflammatory and anti-angiogenic functions. Due to the limited research available about skin protection, this study aims to discern the potential abilities of kahweol and the possible regulation targets. First, the cytotoxicity of kahweol was checked by 3-4-5-dimethylthiazol-2-yl)-2-5-diphenyltetrazolium bromide assay, while 2,20-azino-bis (3ethylbenzothiazoline-6-sulphonic acid) diammonium salt and 1-diphenyl-2-picryl-hydrazyl were used to examine the radical scavenging ability. Polymerase chain reaction analysis was performed to explore the proper time points and doses affecting skin hydration and barrier-related genes. Luciferase assay and Western blotting were used to explore the possible transcription factors. Finally, fludarabine (a STAT1 inhibitor) was chosen to discern the relationship between skin-moisturizing factors and STAT1. We found that HaCaT cells experienced no toxicity from kahweol, and kahweol displayed moderate radical scavenging ability. Moreover, kahweol increased the outcome of HAS1, HAS2, occludin, and TGM-1 from six hours in a dose-dependent manner as well as the activation of STAT1 from six hours. Additionally, kahweol recovered the suppression of HAS2, STAT1-mediated luciferase activity, and HA secretion, which was all downregulated by fludarabine. In this study, we demonstrated that kahweol promotes skin-moisturizing activities by upregulating STAT1.

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