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1.
Zhongguo Yi Liao Qi Xie Za Zhi ; 46(2): 160-163, 2022 Mar 30.
Article in Chinese | MEDLINE | ID: covidwho-1786151

ABSTRACT

Body temperature is an essential physiological parameter. Conducting non-contact, fast and accurate measurement of temperature is increasing important under the background of COVID-19. The study introduces an infrared temperature measurement system based on the thermopile infrared temperature sensor ZTP-135SR. Extracting original temperature date of sensor, post-amplification and filter processing have been performed to ensure accuracy of the system. In addition, the temperature data of environmental compensation which obtained by polynomial fitting is added to the system to further improve measurement accuracy.


Subject(s)
Body Temperature , COVID-19 , Algorithms , Humans , Temperature , Thermometers
2.
J Transl Med ; 20(1): 170, 2022 Apr 11.
Article in English | MEDLINE | ID: covidwho-1785158

ABSTRACT

BACKGROUND: Although numerous studies have explored the impact of meteorological factors on the epidemic of COVID-19, their relationship remains controversial and needs to be clarified. METHODS: We assessed the risk effect of various meteorological factors on COVID-19 infection using the distributed lag nonlinear model, based on related data from July 1, 2020, to June 30, 2021, in eight countries, including Portugal, Greece, Egypt, South Africa, Paraguay, Uruguay, South Korea, and Japan, which are in Europe, Africa, South America, and Asia, respectively. We also explored associations between COVID-19 prevalence and individual meteorological factors by the Spearman's rank correlation test. RESULTS: There were significant non-linear relationships between both temperature and relative humidity and COVID-19 prevalence. In the countries located in the Northern Hemisphere with similar latitudes, the risk of COVID-19 infection was the highest at temperature below 5 â„ƒ. In the countries located in the Southern Hemisphere with similar latitudes, their highest infection risk occurred at around 15 â„ƒ. Nevertheless, in most countries, high temperature showed no significant association with reduced risk of COVID-19 infection. The effect pattern of relative humidity on COVID-19 depended on the range of its variation in countries. Overall, low relative humidity was correlated with increased risk of COVID-19 infection, while the high risk of infection at extremely high relative humidity could occur in some countries. In addition, relative humidity had a longer lag effect on COVID-19 than temperature. CONCLUSIONS: The effects of meteorological factors on COVID-19 prevalence are nonlinear and hysteretic. Although low temperature and relative humidity may lower the risk of COVID-19, high temperature or relative humidity could also be associated with a high prevalence of COVID-19 in some regions.


Subject(s)
COVID-19 , COVID-19/epidemiology , China/epidemiology , Humans , Meteorological Concepts , Nonlinear Dynamics , Prevalence , South Africa , Temperature
3.
BMJ Open ; 12(4): e049383, 2022 Apr 08.
Article in English | MEDLINE | ID: covidwho-1784811

ABSTRACT

OBJECTIVES: Air temperature has been considered a modifiable and contributable variable in COVID-19 transmission. Implementation of non-pharmaceutical interventions (NPIs) has also made an impact on COVID-19 transmission, changing the transmission pattern to intrahousehold transmission under stringent containment measures. Therefore, it is necessary to re-estimate the influence of air temperature on COVID-19 transmission while excluding the influence of NPIs. DESIGN, SETTING AND PARTICIPANTS: This study is a data-based comprehensive modelling analysis. A stochastic epidemiological model, the ScEIQR model (contactable susceptible-exposed-infected-quarantined-removed), was established to evaluate the influence of air temperature and containment measures on the intrahousehold spread of COVID-19. Epidemic data on COVID-19, including daily confirmed cases, number of close contacts, etc, were collected from the National Health Commission of China. OUTCOME MEASURES: The model was fitted using the Metropolis-Hastings algorithm with a cost function based on the least squares method. The LOESS (locally weighted scatterplot smoothing) regression function was used to assess the relationship between air temperature and rate of COVID-19 transmission within the ScEIQR model. RESULTS: The ScEIQR model indicated that the optimal temperature for spread of COVID-19 peaked at 10℃ (50℉), ranging from 5℃ to 14℃ (41℉-57.2℉). In the fitted model, the fitted intrahousehold transmission rate (ß') of COVID-19 was 10.22 (IQR 8.47-12.35) across mainland China. The association between air temperature and ß' of COVID-19 suggests that COVID-19 might be seasonal. Our model also validated the effectiveness of NPIs, demonstrating that diminishing contactable susceptibility (Sc) and avoiding delay in diagnosis and hospitalisation (η) were more effective than contact tracing (κ and ρ). CONCLUSIONS: We constructed a novel epidemic model to estimate the effect of air temperature on COVID-19 transmission beyond implementation of NPIs, which can inform public health strategy and predict the transmission of COVID-19.


Subject(s)
COVID-19 , SARS-CoV-2 , COVID-19/epidemiology , COVID-19/prevention & control , Contact Tracing/methods , Humans , Quarantine , Temperature
4.
Sci Rep ; 11(1): 22027, 2021 11 11.
Article in English | MEDLINE | ID: covidwho-1758313

ABSTRACT

Rising temperature levels during spring and summer are often argued to enable lifting of strict containment measures even in the absence of herd immunity. Despite broad scholarly interest in the relationship between weather and coronavirus spread, previous studies come to very mixed results. To contribute to this puzzle, the paper examines the impact of weather on the COVID-19 pandemic using a unique granular dataset of over 1.2 million daily observations covering over 3700 counties in nine countries for all seasons of 2020. Our results show that temperature and wind speed have a robust negative effect on virus spread after controlling for a range of potential confounding factors. These effects, however, are substantially larger during mealtimes, as well as in periods of high mobility and low containment, suggesting an important role for social behaviour.


Subject(s)
COVID-19/epidemiology , Humans , Humidity , Pandemics , Risk Factors , SARS-CoV-2/isolation & purification , Seasons , Social Behavior , Temperature , Weather , Wind
5.
Sci Rep ; 12(1): 4796, 2022 03 21.
Article in English | MEDLINE | ID: covidwho-1751757

ABSTRACT

The continuing evolution of SARS-CoV-2 variants not only causes a long-term global health concerns but also encounters the vaccine/drug effectiveness. The degree of virus infectivity and its clinical outcomes often depend on various biological parameters (e.g., age, genetic factors, diabetes, obesity and other ailments) of an individual along with multiple environmental factors (e.g., air temperature, humidity, seasons). Thus, despite the extensive search for and use of several vaccine/drug candidates, the combinative influence of these various extrinsic and intrinsic risk factors involved in the SARS-CoV-2 virus infectivity has yet to be explored. Previous studies have reported that environment temperature is negatively associated with virus infectivity for SARS-CoV-2. This study elaborates on our previous findings, investigating the link between environmental temperature and other metabolic parameters, such as average total cholesterol and obesity, with the increase in COVID-19 cases. Statistical analysis conducted on a per country basis not only supports the existence of a significant negative correlation between environmental temperature and SARS-CoV-2 infections but also found a strong positive correlation between COVID-19 cases and these metabolic parameters. In addition, a multiphase growth curve model (GCM) was built to predict the contribution of these covariates in SARS-CoV-2 infectivity. These findings, for first time, support the idea that there might be a combinatorial impact of environmental temperature, average total cholesterol, and obesity in the inflation of the SARS-CoV-2 infectivity.


Subject(s)
COVID-19 , SARS-CoV-2 , Cholesterol , Humans , Obesity , Temperature
6.
Environ Sci Pollut Res Int ; 29(15): 21811-21825, 2022 Mar.
Article in English | MEDLINE | ID: covidwho-1750802

ABSTRACT

The COVID-19 pandemic affected the world through its ability to cause widespread infection. The Middle East including the Kingdom of Saudi Arabia (KSA) has also been hit by the COVID-19 pandemic like the rest of the world. This study aims to examine the relationships between meteorological factors and COVID-19 case counts in three cities of the KSA. The distribution of the COVID-19 case counts was observed for all three cities followed by cross-correlation analysis which was carried out to estimate the lag effects of meteorological factors on COVID-19 case counts. Moreover, the Poisson model and negative binomial (NB) model with their zero-inflated versions (i.e., ZIP and ZINB) were fitted to estimate city-specific impacts of weather variables on confirmed case counts, and the best model is evaluated by comparative analysis for each city. We found significant associations between meteorological factors and COVID-19 case counts in three cities of KSA. We also perceived that the ZINB model was the best fitted for COVID-19 case counts. In this case study, temperature, humidity, and wind speed were the factors that affected COVID-19 case counts. The results can be used to make policies to overcome this pandemic situation in the future such as deploying more resources through testing and tracking in such areas where we observe significantly higher wind speed or higher humidity. Moreover, the selected models can be used for predicting the probability of COVID-19 incidence across various regions.


Subject(s)
COVID-19 , Meteorological Concepts , Pandemics , COVID-19/epidemiology , Cities/epidemiology , Humans , Humidity , Saudi Arabia/epidemiology , Temperature , Wind
7.
Front Immunol ; 13: 837443, 2022.
Article in English | MEDLINE | ID: covidwho-1742219

ABSTRACT

An ideal protective vaccine against SARS-CoV-2 should not only be effective in preventing disease, but also in preventing virus transmission. It should also be well accepted by the population and have a simple logistic chain. To fulfill these criteria, we developed a thermostable, orally administered vaccine that can induce a robust mucosal neutralizing immune response. We used our platform based on retrovirus-derived enveloped virus-like particles (eVLPs) harnessed with variable surface proteins (VSPs) from the intestinal parasite Giardia lamblia, affording them resistance to degradation and the triggering of robust mucosal cellular and antibody immune responses after oral administration. We made eVLPs expressing various forms of the SARS-CoV-2 Spike protein (S), with or without membrane protein (M) expression. We found that prime-boost administration of VSP-decorated eVLPs expressing a pre-fusion stabilized form of S and M triggers robust mucosal responses against SARS-CoV-2 in mice and hamsters, which translate into complete protection from a viral challenge. Moreover, they dramatically boosted the IgA mucosal response of intramuscularly injected vaccines. We conclude that our thermostable orally administered eVLP vaccine could be a valuable addition to the current arsenal against SARS-CoV-2, in a stand-alone prime-boost vaccination strategy or as a boost for existing vaccines.


Subject(s)
COVID-19 Vaccines/immunology , COVID-19/immunology , Coronavirus M Proteins/immunology , Giardia lamblia/immunology , Intestinal Mucosa/immunology , SARS-CoV-2/physiology , Spike Glycoprotein, Coronavirus/immunology , Animals , Antigens, Protozoan/immunology , Cricetinae , Humans , Immunity , Immunization, Secondary , Immunoglobulin A/metabolism , Male , Mice , Mice, Inbred BALB C , Temperature , Vaccine Potency , Vaccines, Virus-Like Particle
8.
J Infect Dis ; 225(6): 957-964, 2022 03 15.
Article in English | MEDLINE | ID: covidwho-1735580

ABSTRACT

Nonpharmaceutical interventions (NPIs) were widely introduced to combat the coronavirus disease 2019 (COVID-19) pandemic. These interventions also likely led to substantially reduced activity of respiratory syncytial virus (RSV). From late 2020, some countries observed out-of-season RSV epidemics. Here, we analyzed the role of NPIs, population mobility, climate, and severe acute respiratory syndrome coronavirus 2 circulation in RSV rebound through a time-to-event analysis across 18 countries. Full (re)opening of schools was associated with an increased risk for RSV rebound (hazard ratio [HR], 23.29 [95% confidence interval {CI}, 1.09-495.84]); every 5°C increase in temperature was associated with a decreased risk (HR, 0.63 [95% CI, .40-.99]). There was an increasing trend in the risk for RSV rebound over time, highlighting the role of increased population susceptibility. No other factors were found to be statistically significant. Further analysis suggests that increasing population susceptibility and full (re)opening of schools could both override the countereffect of high temperatures, which explains the out-of-season RSV epidemics during the COVID-19 pandemic.


Subject(s)
COVID-19/epidemiology , Respiratory Syncytial Virus Infections/epidemiology , Respiratory Syncytial Virus, Human , Climate , Humans , Pandemics , Respiratory Syncytial Virus Infections/prevention & control , Respiratory Syncytial Virus, Human/pathogenicity , Seasons , Temperature
9.
Sci Rep ; 12(1): 3821, 2022 03 09.
Article in English | MEDLINE | ID: covidwho-1735280

ABSTRACT

The effectiveness of containment measures has been shown to depend on both epidemiological and sociological mechanisms, most notably compliance with national lockdown rules. Yet, there has been growing discontent with social distancing rules during national lockdowns across several countries, particularly among certain demographic and socio-economic groups. Using a highly granular dataset on compliance of over 105,000 individuals between March and May 2020 in the United Kingdom (UK), we find that compliance with lockdown policies was initially high in the overall population during the earlier phase of the pandemic, but that compliance fell substantially over time, especially among specific segments of society. Warmer temperatures increased the non-compliance of individuals who are male, divorced, part-time employed, and/or parent of more than two children. Thus, while epidemiologically the virus spread was naturally more limited during the warmer period of 2020, sociologically the higher temperature led to lower individual-level compliance with public health measures. As long as new strains emerge, governments may therefore be required to complement vaccination campaigns with targeted and time limited restrictions. Since non-complying individuals at the beginning of the pandemic share certain characteristics with vaccination sceptics, understanding their compliance behaviour will remain essential for future policymaking.


Subject(s)
COVID-19/epidemiology , Climate , Adult , COVID-19/virology , Female , Humans , Male , Quarantine , SARS-CoV-2/isolation & purification , Socioeconomic Factors , Temperature , Time Factors , United Kingdom/epidemiology
11.
J Synchrotron Radiat ; 29(Pt 2): 549-554, 2022 Mar 01.
Article in English | MEDLINE | ID: covidwho-1730788

ABSTRACT

Data-driven approaches in materials science demand the collection of large amounts of data on the target materials at synchrotron beamlines. To accurately gather suitable experimental data, it is essential to establish fully automated measurement systems to reduce the workload of the beamline staff. Moreover, the recent COVID-19 pandemic has further emphasized the necessity of automated and/or remote measurements at synchrotron beamlines. Here, the installation of a new sample changer combined with a high-temperature furnace and a fully automated alignment system on beamline BL04B2 at SPring-8 is reported. The system allows X-ray total scattering measurements of up to 21 samples at different temperatures (from room temperature to 1200°C) to be conducted without any human assistance.


Subject(s)
COVID-19 , Robotics , Humans , Pandemics , SARS-CoV-2 , Synchrotrons , Temperature , X-Rays
12.
Environ Res ; 206: 112272, 2022 04 15.
Article in English | MEDLINE | ID: covidwho-1719714

ABSTRACT

Studying the influence of weather conditions on the COVID-19 epidemic is an emerging field. However, existing studies in this area tend to utilize time-series data, which have certain limitations and fail to consider individual, social, and economic factors. Therefore, this study aimed to fill this gap. In this paper, we explored the influence of weather conditions on the COVID-19 epidemic using COVID-19-related prefecture-daily panel data collected in mainland China between January 1, 2020, and February 19, 2020. A two-way fixed effect model was applied taking into account factors including public health measures, effective distance to Wuhan, population density, economic development level, health, and medical conditions. We also used a piecewise linear regression to determine the relationship in detail. We found that there is a conditional negative relationship between weather conditions and the epidemic. Each 1 °C rise in mean temperature led to a 0.49% increase in the confirmed cases growth rate when mean temperature was above -7 °C. Similarly, when the relative humidity was greater than 46%, it was negatively correlated with the epidemic, where a 1% increase in relative humidity decreased the rate of confirmed cases by 0.19%. Furthermore, prefecture-level administrative regions, such as Chifeng (included as "warning cities") have more days of "dangerous weather", which is favorable for outbreaks. In addition, we found that the impact of mean temperature is greatest in the east, the influence of relative humidity is most pronounced in the central region, and the significance of weather conditions is more important in the coastal region. Finally, we found that rising diurnal temperatures decreased the negative impact of weather conditions on the spread of COVID-19. We also observed that strict public health measures and high social concern can mitigate the adverse effects of cold and dry weather on the spread of the epidemic. To the best of our knowledge, this is the first study which applies the two-way fixed effect model to investigate the influence of weather conditions on the COVID-19 epidemic, takes into account socio-economic factors and draws new conclusions.


Subject(s)
COVID-19 , China/epidemiology , Humans , SARS-CoV-2 , Temperature , Weather
13.
Viruses ; 14(2)2022 02 10.
Article in English | MEDLINE | ID: covidwho-1715772

ABSTRACT

Enterovirus genus has over one hundred genotypes and could cause several kinds of severe animal and human diseases. Understanding the role of conserved residues in the VP1 capsid protein among the enterovirus genus may lead to anti-enteroviral drug development. The highly conserved residues were found to be located at the loop and ß-barrel intersections. To elucidate the role of these VP1 residues among the enterovirus genus, alanine substitution reverse genetics (rg) variants were generated, and virus properties were investigated for their impact. Six highly conserved residues were identified as located near the inside of the canyon, and four of them were close to the ß-barrel and loop intersection. The variants rgVP1-R86A, rgVP1-P193A, rgVP1-G231A, and rgVP1-K256A were unable to be obtained, which may be due to disruption in the virus replication process. In contrast, rgVP1-E134A and rgVP1-P157A replicated well and rgVP1-P157A showed smaller plaque size, lower viral growth kinetics, and thermal instability at 39.5°C when compared to the rg wild type virus. These findings showed that the conserved residues located at the ß-barrel and loop junction play roles in modulating viral replication, which may provide a pivotal role for pan-enteroviral inhibitor candidate.


Subject(s)
Capsid Proteins/chemistry , Enterovirus/physiology , Virus Replication , Amino Acid Sequence , Antiviral Agents/chemistry , Capsid Proteins/genetics , Cell Line, Tumor , Conserved Sequence , Humans , Mutation , Protein Conformation , Protein Stability , RNA, Viral/metabolism , Small Molecule Libraries/chemistry , Temperature , Viral Load
14.
Viruses ; 14(2)2022 01 21.
Article in English | MEDLINE | ID: covidwho-1715755

ABSTRACT

The interaction of phages with abiotic environmental surfaces is usually an understudied field of phage ecology. In this study, we investigated the virucidal potential of different metal salts, metal and ceramic powders doped with Ag and Cu ions, and newly fabricated ceramic and metal surfaces against Phi6 bacteriophage. The new materials were fabricated by spark plasma sintering (SPS) and/or selective laser melting (SLM) techniques and had different surface free energies and infiltration features. We show that inactivation of Phi6 in solutions with Ag and Cu ions can be as effective as inactivation by pH, temperature, or UV. Adding powder to Ag and Cu ion solutions decreased their virucidal effect. The newly fabricated ceramic and metal surfaces showed very good virucidal activity. In particular, 45%TiO2 + 5%Ag + 45%ZrO2 + 5%Cu, in addition to virus adhesion, showed virucidal and infiltration properties. The results indicate that more than 99.99% of viruses deposited on the new ceramic surface were inactivated or irreversibly attached to it.


Subject(s)
Bacteriophage phi 6/drug effects , Copper/pharmacology , Silver/pharmacology , Bacteriophage phi 6/growth & development , Bacteriophage phi 6/physiology , Ceramics/chemistry , Copper/chemistry , Hydrogen-Ion Concentration , Powders/chemistry , Silver/chemistry , Surface Properties , Temperature
15.
Biochem Biophys Res Commun ; 601: 129-136, 2022 04 23.
Article in English | MEDLINE | ID: covidwho-1699331

ABSTRACT

COVID-19, caused by SARS-CoV-2, has been spreading worldwide for more than two years and has led to immense challenges to human health. Despite the great efforts that have been made, our understanding of SARS-CoV-2 is still limited. The viral helicase, NSP13 is an important enzyme involved in SARS-CoV-2 replication and transcription. Here we highlight the important role of the stalk domain in the enzymatic activity of NSP13. Without the stalk domain, NSP13 loses its dsRNA unwinding ability due to the lack of ATPase activity. The stalk domain of NSP13 also provides a rigid connection between the ZBD and helicase domain. We found that the tight connection between the stalk and helicase is necessary for NSP13-mediated dsRNA unwinding. When a short flexible linker was inserted between the stalk and helicase domains, the helicase activity of NSP13 was impaired, although its ATPase activity remained intact. Further study demonstrated that linker insertion between the stalk and helicase domains attenuated the RNA binding ability and affected the thermal stability of NSP13. In summary, our results suggest the crucial role of the stalk domain in NSP13 enzymatic activity and provide mechanistic insight into dsRNA unwinding by SARS-CoV-2 NSP13.


Subject(s)
COVID-19/prevention & control , Methyltransferases/metabolism , RNA Helicases/metabolism , SARS-CoV-2/metabolism , Viral Nonstructural Proteins/metabolism , Adenosine Triphosphatases/genetics , Adenosine Triphosphatases/metabolism , Binding Sites/genetics , COVID-19/virology , Enzyme Stability , Humans , Methyltransferases/chemistry , Methyltransferases/genetics , Models, Molecular , Mutation , Protein Conformation , RNA/chemistry , RNA/genetics , RNA/metabolism , RNA Helicases/chemistry , RNA Helicases/genetics , Recombinant Proteins/metabolism , SARS-CoV-2/genetics , SARS-CoV-2/physiology , Temperature , Viral Nonstructural Proteins/chemistry , Viral Nonstructural Proteins/genetics
16.
Environ Res ; 208: 112484, 2022 May 15.
Article in English | MEDLINE | ID: covidwho-1693480

ABSTRACT

This paper investigates at the world level the influence of climate on the transmission of the SARS-CoV-2 virus. For that purpose, panel regressions of the number of cases and deaths from 134 countries are run on a set of explanatory variables (air temperature, relative humidity, precipitation, and wind) along with control variables (government interventions and population size and density). The analysis is completed with a panel threshold regression to check for potential non-linearities of the weather variables on virus transmission. The main findings support the role of climate in the circulation of the virus across countries. The detailed analysis reveals that relative humidity reduces the number of cases and deaths in both low and high regimes, while temperature and wind reduce the number of deaths.


Subject(s)
COVID-19 , Climate , Communicable Disease Control , Pandemics , COVID-19/epidemiology , COVID-19/prevention & control , Government , Humans , Humidity , Pandemics/prevention & control , SARS-CoV-2 , Temperature , Weather
17.
Med Eng Phys ; 102: 103777, 2022 Apr.
Article in English | MEDLINE | ID: covidwho-1693116

ABSTRACT

Non-contact infrared sensors are widely used as a diagnostic tool for elevated body temperature during initial screening for coronaviruses. The aim of this study was to investigate the thermal differences at three anatomical points: temple, forehead, and wrist, in the initial screening for temperature indicative of febrile and non-febrile states in skin pigmentation variations in Black, Half-Black and Caucasian skins, correlated with height and weight variables. Temperatures were obtained by means of an infrared thermometer in 289 volunteers with mean age of 18.30 ± 0.76, in a controlled environment according to Singapore Standard, SS582 part 1 and 2, normative standard IEC 80601-2-59, with standard technical protocols established by the International Organization for Standardization, ISO / TR 13154. The data were processed in MATLAB® R2021a, and data normality verified by Kolmogorov-Smirnov test, non-parametric data paired between temple / forehead / wrist were compared using the Wilcoxon signed-rank test. The results show different median temperatures in these anatomical regions, 37.2°C at the temple, 36.8°C at the forehead and 36.4°C at the wrist. As the temple region presents a temperature higher than the other investigated regions and, therefore, close to the core temperature, it should be considered for the initial screening of SARS-CoV-2 when using non-contact infrared thermometers. Furthermore, no significant changes were found due to variation in skin tone, height, or weight.


Subject(s)
COVID-19 , Forehead , Adolescent , Adult , Body Temperature , COVID-19/diagnosis , Humans , SARS-CoV-2 , Technology , Temperature , Wrist , Young Adult
18.
Sensors (Basel) ; 22(3)2022 Jan 22.
Article in English | MEDLINE | ID: covidwho-1686937

ABSTRACT

There is a need to rapidly screen individuals for heat strain and fever using skin temperature (Tsk) as an index of deep body temperature (Tb). This study's aim was to assess whether Tsk could serve as an accurate and valid index of Tb during a simulated heatwave. Seven participants maintained a continuous schedule over 9-days, in 3-day parts; pre-/post-HW (25.4 °C), simulated-HW (35.4 °C). Contact thermistors measured Tsk (Tforehead, Tfinger); radio pills measured gastrointestinal temperature (Tgi). Proximal-distal temperature gradients (ΔTforehead-finger) were also measured. Measurements were grouped into ambient conditions: 22, 25, and 35 °C. Tgi and Tforehead only displayed a significant relationship in 22 °C (r: 0.591; p < 0.001) and 25 °C (r: 0.408; p < 0.001) conditions. A linear regression of all conditions identified Tforehead and ΔTforehead-finger as significant predictors of Tgi (r2: 0.588; F: 125.771; p < 0.001), producing a root mean square error of 0.26 °C. Additional residual analysis identified Tforehead to be responsible for a plateau in Tgi prediction above 37 °C. Contact Tforehead was shown to be a statistically suitable indicator of Tgi in non-HW conditions; however, an error of ~1 °C makes this physiologically redundant. The measurement of multiple sites may improve Tb prediction, though it is still physiologically unsuitable, especially at higher ambient temperatures.


Subject(s)
Body Temperature , Skin Temperature , Fever , Forehead , Hot Temperature , Humans , Temperature
19.
FASEB J ; 36(3): e22199, 2022 03.
Article in English | MEDLINE | ID: covidwho-1684809

ABSTRACT

Spike trimer plays a key role in SARS-CoV-2 infection and vaccine development. It consists of a globular head and a flexible stalk domain that anchors the protein into the viral membrane. While the head domain has been extensively studied, the properties of the adjoining stalk are poorly understood. Here, we characterize the coiled-coil formation and thermodynamic stability of the stalk domain and its segments. We find that the N-terminal segment of the stalk does not form coiled-coils and remains disordered in solution. The C-terminal stalk segment forms a trimeric coiled-coil in solution, which becomes significantly stabilized in the context of the full-length stalk. Its crystal structure reveals a novel antiparallel tetramer coiled-coil with an unusual combination of a-d and e-a-d hydrophobic core packing. Structural analysis shows that a subset of hydrophobic residues stabilizes different coiled-coil structures: trimer, tetramer, and heterohexamer, underscoring a highly polymorphic nature of the SARS-CoV-2 stalk sequence.


Subject(s)
COVID-19/virology , Models, Molecular , Protein Domains , SARS-CoV-2/chemistry , Spike Glycoprotein, Coronavirus/chemistry , Amino Acid Sequence , Crystallization , Crystallography, X-Ray , Humans , Hydrophobic and Hydrophilic Interactions , Protein Stability , Protein Structure, Secondary , Scattering, Small Angle , Temperature , X-Ray Diffraction
20.
J Mater Chem B ; 9(47): 9642-9657, 2021 12 08.
Article in English | MEDLINE | ID: covidwho-1684136

ABSTRACT

Cancer is a growing threat to human beings. Traditional treatments for malignant tumors usually involve invasive means to healthy human tissues, such as surgical treatment and chemotherapy. In recent years the use of specific stimulus-responsive materials in combination with some non-contact, non-invasive stimuli can lead to better efficacy and has become an important area of research. It promises to develop personalized treatment systems for four types of physical stimuli: light, ultrasound, magnetic field, and temperature. Nanomaterials that are responsive to these stimuli can be used to enhance drug delivery, cancer treatment, and tissue engineering. This paper reviews the principles of the stimuli mentioned above, their effects on materials, and how they work with nanomaterials. For this aim, we focus on specific applications in controlled drug release, cancer therapy, tissue engineering, and virus detection, with particular reference to recent photothermal, photodynamic, sonodynamic, magnetothermal, radiation, and other types of therapies. It is instructive for the future development of stimulus-responsive nanomaterials for these aspects.


Subject(s)
Antineoplastic Agents/therapeutic use , Delayed-Action Preparations/therapeutic use , Metal Nanoparticles/therapeutic use , Neoplasms/drug therapy , Radiation-Sensitizing Agents/therapeutic use , Animals , Antineoplastic Agents/chemistry , Antineoplastic Agents/radiation effects , Delayed-Action Preparations/chemistry , Delayed-Action Preparations/radiation effects , Humans , Infrared Rays , Magnetic Phenomena , Metal Nanoparticles/chemistry , Metal Nanoparticles/radiation effects , Radiation-Sensitizing Agents/chemistry , Radiation-Sensitizing Agents/radiation effects , SARS-CoV-2/isolation & purification , Temperature , Tissue Engineering/methods , Ultrasonic Waves , Viral Load/methods
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