Your browser doesn't support javascript.
Show: 20 | 50 | 100
Results 1 - 6 de 6
Filter
1.
Front Public Health ; 9: 700473, 2021.
Article in English | MEDLINE | ID: covidwho-1775817

ABSTRACT

With the proliferation of tobacco products, there might be a need for more complex models than current two-product models. We have developed a three-product model able to represent interactions between three products in the marketplace. We also investigate if using several implementations of two-product models could provide sufficient information to assess 3 coexisting products. Italy is used as case-study with THPs and e-cigarettes as the products under investigation. We use transitions rates estimated for THPs in Japan and e-cigarettes in the USA to project what could happen if the Italian population were to behave as the Japanese for THP or USA for e-cigarettes. Results suggest that three-product models may be hindered by data availability while two product models could miss potential synergies between products. Both, THP and E-Cigarette scenarios, led to reduction in life-years lost although the Japanese THP scenario reductions were 3 times larger than the USA e-cigarette projections.


Subject(s)
Electronic Nicotine Delivery Systems , Tobacco Products , Heating/methods , Humans , Tobacco
2.
Nat Commun ; 13(1): 968, 2022 02 18.
Article in English | MEDLINE | ID: covidwho-1705624

ABSTRACT

DNA/RNA-gold nanoparticle (DNA/RNA-AuNP) nanoprobes have been widely employed for nanobiotechnology applications. Here, we discover that both thiolated and non-thiolated DNA/RNA can be efficiently attached to AuNPs to achieve high-stable spherical nucleic acid (SNA) within minutes under a domestic microwave (MW)-assisted heating-dry circumstance. Further studies show that for non-thiolated DNA/RNA the conjugation is poly (T/U) tag dependent. Spectroscopy, test strip hybridization, and loading counting experiments indicate that low-affinity poly (T/U) tag mediates the formation of a standing-up conformation, which is distributed in the outer layer of SNA structure. In further application studies, CRISPR/Cas9-sgRNA (136 bp), SARS-CoV-2 RNA fragment (1278 bp), and rolling circle amplification (RCA) DNA products (over 1000 bp) can be successfully attached on AuNPs, which overcomes the routine methods in long-chain nucleic acid-AuNP conjugation, exhibiting great promise in biosensing and nucleic acids delivery applications. Current heating-dry strategy has improved traditional DNA/RNA-AuNP conjugation methods in simplicity, rapidity, cost, and universality.


Subject(s)
Biosensing Techniques/methods , Gold/chemistry , Metal Nanoparticles/chemistry , Biotechnology/methods , COVID-19/diagnosis , COVID-19/virology , COVID-19 Nucleic Acid Testing/methods , DNA/chemistry , Heating/methods , Humans , Limit of Detection , Microwaves , Nanomedicine/methods , RNA, Viral/chemistry , RNA, Viral/genetics , RNA, Viral/isolation & purification , SARS-CoV-2/genetics
3.
PLoS One ; 15(7): e0234851, 2020.
Article in English | MEDLINE | ID: covidwho-627997

ABSTRACT

A lack of N95 Filtering Facepiece Respirators (FFRs) during the COVID-19 crisis has placed healthcare workers at risk. It is important for any N95 reuse strategy to determine the effects that proposed protocols would have on the physical functioning of the mask, as well as the practical aspects of implementation. Here we propose and implement a method of heating N95 respirators with moisture (85°C, 60-85% humidity). We test both mask filtration efficiency and fit to validate this process. Our tests focus on the 3M 1860, 3M 1870, and 3M 8210 Plus N95 models. After five cycles of the heating procedure, all three respirators pass both quantitative fit testing (score of >100) and show no degradation of mask filtration efficiency. We also test the Chen Heng V9501 KN95 and HKYQ N95 finding no degradation of mask filtration efficiency, however even for unheated masks these scored <50 for every fit test. The heating method presented here is scalable from individual masks to over a thousand a day with a single industrial convection oven, making this method practical for local application inside health-care facilities.


Subject(s)
Betacoronavirus , Coronavirus Infections/epidemiology , Decontamination/methods , Equipment Reuse , Heating/methods , Humidity , Masks/virology , Pneumonia, Viral/epidemiology , Respiratory Protective Devices/virology , COVID-19 , Coronavirus Infections/virology , Filtration/instrumentation , Humans , Materials Testing/methods , Occupational Exposure/prevention & control , Pandemics , Pneumonia, Viral/virology , SARS-CoV-2
4.
Crit Care ; 24(1): 194, 2020 05 06.
Article in English | MEDLINE | ID: covidwho-186516

ABSTRACT

The aim of this review is to describe variation in standards and guidelines on 'heating, ventilation and air-conditioning (HVAC)' system maintenance in the intensive care units, across the world, which is required to maintain good 'indoor air quality' as an important non-pharmacological strategy in preventing hospital-acquired infections. An online search and review of standards and guidelines published by various societies including American Institute of Architects (AIA), American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE), Centers for Disease Control and Prevention (CDC), Department of Health Estates and Facilities Division, Health Technical Memorandum 2025 (HTM) and Healthcare Infection Control Practices Advisory Committee (HICPAC) along with various national expert committee consensus statements, regional and hospital-based protocols available in a public domain were retrieved. Selected publications and textbooks describing HVAC structural aspects were also reviewed, and we described the basic structural details of HVAC system as well as variations in the practised standards of HVAC system in the ICU, worldwide. In summary, there is a need of universal standards for HVAC system with a specific mention on the type of ICU, which should be incorporated into existing infection control practice guidelines.


Subject(s)
Air Conditioning/methods , Heating/methods , Ventilation/methods , Air Conditioning/trends , Air Pollution, Indoor/analysis , Heating/trends , Humans , Infection Control/instrumentation , Infection Control/methods , Infection Control/trends , Intensive Care Units/organization & administration , Particulate Matter/adverse effects
5.
ACS Nano ; 14(5): 6348-6356, 2020 May 26.
Article in English | MEDLINE | ID: covidwho-175663

ABSTRACT

The coronavirus disease 2019 (COVID-19) pandemic has led to a major shortage of N95 respirators, which are essential for protecting healthcare professionals and the general public who may come into contact with the virus. Thus, it is essential to determine how we can reuse respirators and other personal protective equipment in these urgent times. We investigated multiple commonly used disinfection schemes on media with particle filtration efficiency of 95%. Heating was recently found to inactivate the virus in solution within 5 min at 70 °C and is among the most scalable, user-friendly methods for viral disinfection. We found that heat (≤85 °C) under various humidities (≤100% relative humidity, RH) was the most promising, nondestructive method for the preservation of filtration properties in meltblown fabrics as well as N95-grade respirators. At 85 °C, 30% RH, we were able to perform 50 cycles of heat treatment without significant changes in the filtration efficiency. At low humidity or dry conditions, temperatures up to 100 °C were not found to alter the filtration efficiency significantly within 20 cycles of treatment. Ultraviolet (UV) irradiation was a secondary choice, which was able to withstand 10 cycles of treatment and showed small degradation by 20 cycles. However, UV can potentially impact the material strength and subsequent sealing of respirators. Finally, treatments involving liquids and vapors require caution, as steam, alcohol, and household bleach all may lead to degradation of the filtration efficiency, leaving the user vulnerable to the viral aerosols.


Subject(s)
Disinfection/methods , Masks/standards , Respiratory Protective Devices/standards , Disinfection/standards , Heating/methods , Textiles/standards
6.
Med Hypotheses ; 141: 109781, 2020 Aug.
Article in English | MEDLINE | ID: covidwho-116780

ABSTRACT

The world is facing a pandemic of unseen proportions caused by a corona virus named SARS-CoV-2 with unprecedent worldwide measures being taken to tackle its contagion. Person-to-person transmission is accepted but WHO only considers aerosol transmission when procedures or support treatments that produce aerosol are performed. Transmission mechanisms are not fully understood and there is evidence for an airborne route to be considered, as the virus remains viable in aerosols for at least 3 h and that mask usage was the best intervention to prevent infection. Heating, Ventilation and Air Conditioning Systems (HVAC) are used as a primary infection disease control measure. However, if not correctly used, they may contribute to the transmission/spreading of airborne diseases as proposed in the past for SARS. The authors believe that airborne transmission is possible and that HVAC systems when not adequately used may contribute to the transmission of the virus, as suggested by descriptions from Japan, Germany, and the Diamond Princess Cruise Ship. Previous SARS outbreaks reported at Amoy Gardens, Emergency Rooms and Hotels, also suggested an airborne transmission. Further studies are warranted to confirm our hypotheses but the assumption of such way of transmission would cause a major shift in measures recommended to prevent infection such as the disseminated use of masks and structural changes to hospital and other facilities with HVAC systems.


Subject(s)
Air Microbiology , Betacoronavirus/isolation & purification , Coronavirus Infections/transmission , Environment, Controlled , Pandemics , Pneumonia, Viral/transmission , Ventilation , Aerosols , Air Conditioning/adverse effects , Air Conditioning/instrumentation , Air Conditioning/methods , Air Pollution, Indoor , COVID-19 , Coronavirus Infections/prevention & control , Cross Infection/transmission , Equipment Contamination , Equipment Design , Equipment Failure , Fomites/virology , Heating/adverse effects , Heating/instrumentation , Heating/methods , Humans , Legionnaires' Disease/epidemiology , Legionnaires' Disease/transmission , Models, Biological , Pandemics/prevention & control , Pneumonia, Viral/prevention & control , SARS-CoV-2 , Sanitary Engineering/instrumentation , Severe Acute Respiratory Syndrome/epidemiology , Severe Acute Respiratory Syndrome/transmission , Sewage/virology , Ventilation/instrumentation , Ventilation/methods
SELECTION OF CITATIONS
SEARCH DETAIL