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1.
Foods ; 11(14)2022 Jul 14.
Article in English | MEDLINE | ID: covidwho-1938751

ABSTRACT

Innovative application of surface-enhanced Raman scattering (SERS) for rapid and nondestructive analyses has been gaining increasing attention for food safety and quality. SERS is based on inelastic scattering enhancement from molecules located near nanostructured metallic surfaces and has many advantages, including ultrasensitive detection and simple protocols. Current SERS-based quality analysis contains composition and structural information that can be used to establish an electronic file of the food samples for subsequent reference and traceability. SERS is a promising technique for the detection of chemical, biological, and harmful metal contaminants, as well as for food poisoning, and allergen identification using label-free or label-based methods, based on metals and semiconductors as substrates. Recognition elements, including immunosensors, aptasensors, or molecularly imprinted polymers, can be linked to SERS tags to specifically identify targeted contaminants and perform authenticity analysis. Herein, we highlight recent studies on SERS-based quality and safety analysis for different foods categories spanning the whole food chain, 'from farm to table' and processing, genetically modified food, and novel foods. Moreover, SERS detection is a potential tool that ensures food safety in an easy, rapid, reliable, and nondestructive manner during the COVID-19 pandemic.

3.
EuropePMC; 2021.
Preprint in English | EuropePMC | ID: ppcovidwho-306644

ABSTRACT

Background: Taylor’s law, which formulates a power-law relationship between the variance and the mean, is used to assess the convergence over time to the spatial uniformity of the density of new infections in Italian provinces during the Covid-19 pandemic. Methods: Using the frequency of the number of new daily COVID 19 infections in the 110 Italian provinces during the period from 25 February 2020 to 15 March 2021, we estimated Taylor's Law using a system of simultaneous equations in five time sub-periods. Results: The infection in Italy initially manifested itself almost exclusively in a few provinces in the north and was very intense. Within a month, the infection spread to the whole country, with varying intensity between provinces. Subsequently, partly as a result of the introduction of containment measures or their relaxation, the infection manifested itself in different ways depending on both the time frame and the geographical area. Conclusions: Our results show that Taylor’s law fits well the temporal dynamics of infection density and can therefore be considered as a useful tool to predict the spatial variability of the Covid-19 infection density. Its slope parameter reflects the temporal correlation of infection density and the effect of nationwide lockdown on the disease spread through the lens of two stochastic population growth models. Our finding suggests that Taylor's law may be used to monitor the Covid-19 outbreak development and to predict the spatial spread of the infection density in the Italian provinces in successive pandemic waves of Covid-19.

4.
EuropePMC; 2020.
Preprint in English | EuropePMC | ID: ppcovidwho-318614

ABSTRACT

Excessive inflammatory responses induced upon SARS-CoV-2 infection interlocks with severe symptoms and acute lung injury in patients with Severe Coronavirus Disease 2019 (COVID-19). Revealing the mechanism underlying the control of SARS-CoV-2-triggered immune-inflammatory responses would help us to understand the pathological process and guide clinical treatment. However, the effect of the NLRP3 inflammasome on regulating SARS-CoV-2-induced inflammatory responses has not been reported. Here, we revealed a distinct mechanism by which SARS-CoV-2 nucleocapsid (N) protein promotes the NLRP3 inflammasome activation to induce hyperinflammation. We demonstrated that N protein facilitates the maturation of proinflammatory cytokines IL-1β and IL-6 and induces proinflammatory responses in cultured cells and mice tissues. In team of molecular mechanism, N protein interacts directly with NLRP3 protein, promotes the binding of NLRP3 with ASC, and facilitates the assemble of the inflammasome complex. More importantly, N protein aggravates lung injury, accelerated death in sepsis and acute inflammation mouse models, and promotes IL-1β and IL-6 activation in mice. Notably, N-induced lung injury and cytokine production were blocked by Ac-YVAD-cmk, an inhibitor of the NLRP3 inflammasome. Therefore, this study revealed a distinct mechanism by which SARS-CoV-2 N protein promotes the NLRP3 inflammasome activation and induces excessive inflammatory responses.

5.
Infect Control Hosp Epidemiol ; : 1-7, 2022 Jan 31.
Article in English | MEDLINE | ID: covidwho-1661937

ABSTRACT

OBJECTIVE: To improve appropriate antibiotic prescribing for children in Tennessee. DESIGN: We performed a before-and-after intervention study with 3 comparison periods: period 1 (P1, baseline) May 2018-September 2019; period 2 (P2, intervention before the COVID-19 pandemic) November 11, 2019-March 20, 2020; and period 3 (P3, intervention during the coronavirus disease 2019 [COVID-19] pandemic) March 21, 2020-November 10, 2020. We additionally surveyed participating providers to assess acceptance of the intervention. SETTING: Community general pediatrics practices. PARTICIPANTS: In total, 81 general pediatricians, family medicine physicians, and nurse practitioners in 5 general pediatrics practices participated in this study. INTERVENTIONS: Each practice identified a practice and operations champion for the project. Practices chose 2-4 implementation strategies previously shown to be effective at reducing outpatient antibiotic use to implement in their practice throughout the study intervention period. Study personnel also held quarterly meetings with all providers to review deidentified peer comparison feedback both across practices enrolled in the study and at the provider level within each practice. RESULTS: We detected improvements in guideline-concordant antibiotic use in the pre-COVID-19 intervention period, and they were sustained in the study period during the pandemic (P3): otitis media (P1 72.14% vs P2 81.42% vs P3 86.11%), group A streptococcal pharyngitis (P1 66.13% vs P2 81.56% vs P3 80.44%), pneumonia (P1 70.6% vs P2 76.2% vs P3 100%), sinusitis (P1 76.2% vs P2 83.78% vs P3 82.86%), skin and soft-tissue infections (P1 97.18% vs P2 100% vs P3 100%). CONCLUSIONS: Bundled implementation strategies led to significant increases in guideline-concordant antibiotic prescribing for all diagnoses. Survey results demonstrate that the bundled implementation strategies were well-accepted by providers.

6.
Sustainability ; 14(2):1029, 2022.
Article in English | ProQuest Central | ID: covidwho-1639276

ABSTRACT

Economic growth is an integral part of the Sustainable Development Goals (SDGs), especially SDG 8. We combine 10 economic constraints and build a five-variable (structural vector autoregressive) SVAR model based on China’s time series data of 1978–2017. The empirical results show: (1) The Chinese government adopted different economic policies at different stages of reform and opening up;(2) From the impulse response results, China’s excessively high government debt ratio has begun to inhibit economic growth;(3) In terms of policy selection and coordination, the Chinese government mostly adopts a “discretion” adjustment strategy. In most cases, the fiscal and monetary policies were in the same direction, and the “double expansionary” and “double contractionary” policy coordination may become mainstream;(4) The results of variance decomposition showed that both fiscal and monetary policies can effectively regulate economic growth at the present stage, and the contribution rates of exogenous shocks to the prediction variance of economic growth rate were about 25%.

7.
J Infect Dis ; 225(1): 5-9, 2022 01 05.
Article in English | MEDLINE | ID: covidwho-1604603

ABSTRACT

From December 2020 to June 2021, 1654487 blood donors were tested for antibodies to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) S1 protein, and 1028547 (62.17%) were reactive. A rapid increase in prevalence was due to vaccination. Among a subset of 1567446 donors, 729771 (46.56%) reported SARS-CoV-2 vaccination, of whom 633769 (86.84%) were S1-antibody reactive only in response to vaccination and 68269 (9.35%) were reactive to both S1 and nucleocapsid in response to prior infection; the remainder were not reactive to either antibody. Among the 837675 (53.44%) donors who did not report vaccination, 210022 (25.07%) had reactivity to both antibodies and 29446 (3.52%) to S1 only.


Subject(s)
Antibodies, Neutralizing/blood , Antibodies, Viral/blood , Antibody Formation , Blood Donors , COVID-19 Vaccines/administration & dosage , COVID-19/prevention & control , SARS-CoV-2/isolation & purification , Adolescent , Adult , Aged , Aged, 80 and over , COVID-19/epidemiology , COVID-19 Testing , Female , Humans , Male , Middle Aged , SARS-CoV-2/immunology , Spike Glycoprotein, Coronavirus , United States/epidemiology , Vaccination , Young Adult
9.
J Infect Dis ; 225(1): 5-9, 2022 01 05.
Article in English | MEDLINE | ID: covidwho-1462361

ABSTRACT

From December 2020 to June 2021, 1654487 blood donors were tested for antibodies to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) S1 protein, and 1028547 (62.17%) were reactive. A rapid increase in prevalence was due to vaccination. Among a subset of 1567446 donors, 729771 (46.56%) reported SARS-CoV-2 vaccination, of whom 633769 (86.84%) were S1-antibody reactive only in response to vaccination and 68269 (9.35%) were reactive to both S1 and nucleocapsid in response to prior infection; the remainder were not reactive to either antibody. Among the 837675 (53.44%) donors who did not report vaccination, 210022 (25.07%) had reactivity to both antibodies and 29446 (3.52%) to S1 only.


Subject(s)
Antibodies, Neutralizing/blood , Antibodies, Viral/blood , Antibody Formation , Blood Donors , COVID-19 Vaccines/administration & dosage , COVID-19/prevention & control , SARS-CoV-2/isolation & purification , Adolescent , Adult , Aged , Aged, 80 and over , COVID-19/epidemiology , COVID-19 Testing , Female , Humans , Male , Middle Aged , SARS-CoV-2/immunology , Spike Glycoprotein, Coronavirus , United States/epidemiology , Vaccination , Young Adult
12.
Signal Transduct Target Ther ; 6(1): 304, 2021 08 17.
Article in English | MEDLINE | ID: covidwho-1361622

ABSTRACT

A comprehensive analysis of the humoral immune response to the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is essential in understanding COVID-19 pathogenesis and developing antibody-based diagnostics and therapy. In this work, we performed a longitudinal analysis of antibody responses to SARS-CoV-2 proteins in 104 serum samples from 49 critical COVID-19 patients using a peptide-based SARS-CoV-2 proteome microarray. Our data show that the binding epitopes of IgM and IgG antibodies differ across SARS-CoV-2 proteins and even within the same protein. Moreover, most IgM and IgG epitopes are located within nonstructural proteins (nsps), which are critical in inactivating the host's innate immune response and enabling SARS-CoV-2 replication, transcription, and polyprotein processing. IgM antibodies are associated with a good prognosis and target nsp3 and nsp5 proteases, whereas IgG antibodies are associated with high mortality and target structural proteins (Nucleocapsid, Spike, ORF3a). The epitopes targeted by antibodies in patients with a high mortality rate were further validated using an independent serum cohort (n = 56) and using global correlation mapping analysis with the clinical variables that are associated with COVID-19 severity. Our data provide fundamental insight into humoral immunity during SARS-CoV-2 infection. SARS-CoV-2 immunogenic epitopes identified in this work could also help direct antibody-based COVID-19 treatment and triage patients.


Subject(s)
Antibodies, Viral/immunology , COVID-19/immunology , Immunity, Humoral , SARS-CoV-2/immunology , Viral Nonstructural Proteins/immunology , COVID-19/mortality , Critical Illness , Disease-Free Survival , Epitopes/immunology , Female , Humans , Immunoglobulin G/immunology , Immunoglobulin M/immunology , Male , Protein Array Analysis , Survival Rate
13.
Nat Commun ; 12(1): 4664, 2021 08 02.
Article in English | MEDLINE | ID: covidwho-1338538

ABSTRACT

Excessive inflammatory responses induced upon SARS-CoV-2 infection are associated with severe symptoms of COVID-19. Inflammasomes activated in response to SARS-CoV-2 infection are also associated with COVID-19 severity. Here, we show a distinct mechanism by which SARS-CoV-2 N protein promotes NLRP3 inflammasome activation to induce hyperinflammation. N protein facilitates maturation of proinflammatory cytokines and induces proinflammatory responses in cultured cells and mice. Mechanistically, N protein interacts directly with NLRP3 protein, promotes the binding of NLRP3 with ASC, and facilitates NLRP3 inflammasome assembly. More importantly, N protein aggravates lung injury, accelerates death in sepsis and acute inflammation mouse models, and promotes IL-1ß and IL-6 activation in mice. Notably, N-induced lung injury and cytokine production are blocked by MCC950 (a specific inhibitor of NLRP3) and Ac-YVAD-cmk (an inhibitor of caspase-1). Therefore, this study reveals a distinct mechanism by which SARS-CoV-2 N protein promotes NLRP3 inflammasome activation and induces excessive inflammatory responses.


Subject(s)
COVID-19/metabolism , Coronavirus Nucleocapsid Proteins/metabolism , Inflammasomes/metabolism , Inflammation/metabolism , NLR Family, Pyrin Domain-Containing 3 Protein/metabolism , SARS-CoV-2/metabolism , Animals , COVID-19/virology , Cells, Cultured , Cytokines/metabolism , HEK293 Cells , Humans , Inflammasomes/genetics , Lung Injury/genetics , Lung Injury/metabolism , Male , Mice, Inbred C57BL , Mice, Knockout , NLR Family, Pyrin Domain-Containing 3 Protein/genetics , Phosphoproteins/metabolism , Protein Binding , SARS-CoV-2/physiology , THP-1 Cells
14.
Transfus Med Rev ; 35(3): 1-7, 2021 07.
Article in English | MEDLINE | ID: covidwho-1331265

ABSTRACT

In the United States, many blood collection organizations initiated programs to test all blood donors for antibodies to SARS-CoV-2, as a measure to increase donations and to assist in the identification of potential donors of COVID-19 convalescent plasma (CCP). As a result, it was possible to investigate the characteristics of healthy blood donors who had previously been infected with SARS-CoV-2. We report the findings from all blood donations collected by the American Red Cross, representing 40% of the national blood supply covering 44 States, in order to characterize the seroepidemiology of SARS-CoV-2 infection among blood donors in the United States, prior to authorized vaccine availability. We performed an observational cohort study from June 15th to November 30th, 2020 on a population of 1.531 million blood donors tested for antibodies to the S1 spike antigen of SARS-CoV-2 by person, place, time, ABO group and dynamics of test reactivity, with additional information from a survey of a subset of those with reactive test results. The overall seroreactivity was 4.22% increasing from 1.18 to 9.67% (June 2020 - November 2020); estimated incidence was 11.6 per hundred person-years, 1.86-times higher than that based upon reported cases in the general population over the same period. In multivariable analyses, seroreactivity was highest in the Midwest (5.21%), followed by the South (4.43%), West (3.43%) and Northeast (2.90%). Seroreactivity was highest among donors aged 18-24 (Odds Ratio 3.02 [95% Confidence Interval 2.80-3.26] vs age >55), African-Americans and Hispanics (1.50 [1.24-1.80] and 2.12 [1.89-2.36], respectively, vs Caucasian). Group O frequency was 51.5% among nonreactive, but 46.1% among seroreactive donors (P< .0001). Of surveyed donors, 45% reported no COVID-19-related symptoms, but 73% among those unaware of testing. Signal levels of antibody tests were stable over 120 days or more and there was little evidence of reinfection. Evaluation of a large population of healthy, voluntary blood donors provided evidence of widespread and increasing SARS-CoV-2 seroprevalence and demonstrated that at least 45% of those previously infected were asymptomatic. Epidemiologic findings were similar to those among clinically reported cases.


Subject(s)
Antibodies, Viral/blood , Blood Donors , COVID-19 Serological Testing , COVID-19/diagnosis , COVID-19/epidemiology , SARS-CoV-2/immunology , Adolescent , Adult , Aged , Asymptomatic Infections , Biomarkers/blood , COVID-19/blood , COVID-19/therapy , COVID-19 Vaccines , Female , Humans , Immunization, Passive , Male , Middle Aged , Seroepidemiologic Studies , United States/epidemiology , Young Adult
15.
Asian Nurs Res (Korean Soc Nurs Sci) ; 15(3): 215-221, 2021 Aug.
Article in English | MEDLINE | ID: covidwho-1293550

ABSTRACT

PURPOSE: The aim of this study was to examine the behavioral responses of pregnant women during the early stage of Coronavirus Disease 2019 (COVID-19) outbreak. METHODS: We recruited 1,099 women to complete an online questionnaire survey from February 10 to February 25, 2020. The subjects were divided into two groups (the pregnant women group and the control group). RESULTS: Concerns about infection: most of the participants watched the COVID-19 news at least once a day. Protective behaviors: the utilization rate of pregnant women (often using various measures) was higher than that of nonpregnant women. Exercise: 30.6% of the pregnant women continued to exercise at home, whereas in the control group, this percentage was 8.4%. Spouse relationship: 38.8% of the subjects' relationship improved, whereas only 2.3% thought the relationship was getting worse. CONCLUSION: Pregnant women had some unique behavioral responses different from that of nonpregnant women. It is important to understand the behavioral responses of pregnant women in this network era.


Subject(s)
Anxiety/epidemiology , Anxiety/psychology , COVID-19/psychology , Depression/psychology , Pregnancy Complications, Infectious/psychology , Pregnant Women/psychology , Adult , COVID-19/epidemiology , China , Cross-Sectional Studies , Depression/epidemiology , Female , Humans , Pregnancy , Pregnancy Complications, Infectious/prevention & control
16.
Ther Adv Respir Dis ; 15: 17534666211009407, 2021.
Article in English | MEDLINE | ID: covidwho-1199884

ABSTRACT

BACKGROUND AND AIMS: The application of prone positioning with acute hypoxemic respiratory failure (AHRF) or acute respiratory distress syndrome (ARDS) in non-intubation patients is increasing gradually, applying prone positioning for more high-flow nasal oxygen therapy (HFNC) and non-invasive ventilation (NIV) patients. This meta-analysis evaluates the efficacy and tolerance of prone positioning combined with non-invasive respiratory support in patients with AHRF or ARDS. METHODS: We searched randomized controlled trials (RCTs) (prospective or retrospective cohort studies, RCTs and case series) published in PubMed, EMBASE and the Cochrane Central Register of Controlled Trials from 1 January 2000 to 1 July 2020. We included studies that compared prone and supine positioning with non-invasive respiratory support in awake patients with AHRF or ARDS. The meta-analyses used random effects models. The methodological quality of the RCTs was evaluated using the Newcastle-Ottawa quality assessment scale. RESULTS: A total of 16 studies fulfilled selection criteria and included 243 patients. The aggregated intubation rate and mortality rate were 33% [95% confidence interval (CI): 0.26-0.42, I2 = 25%], 4% (95% CI: 0.01-0.07, I2 = 0%), respectively, and the intolerance rate was 7% (95% CI: 0.01-0.12, I2 = 5%). Prone positioning increased PaO2/FiO2 [mean difference (MD) = 47.89, 95% CI: 28.12-67.66; p < 0.00001, I2 = 67%] and SpO2 (MD = 4.58, 95% CI: 1.35-7.80, p = 0.005, I2 = 97%), whereas it reduced respiratory rate (MD = -5.01, 95% CI: -8.49 to -1.52, p = 0.005, I2 = 85%). Subgroup analyses demonstrated that the intubation rate of shorter duration prone (⩽5 h/day) and longer duration prone (>5 h/day) were 34% and 21%, respectively; and the mortality rate of shorter duration prone (⩽5 h/day) and longer duration prone (>5 h/day) were 6% and 0%, respectively. PaO2/FiO2 and SpO2 were significantly improved in COVID-19 patients and non-COVID-19 patients. CONCLUSION: Prone positioning could improve the oxygenation and reduce respiratory rate in both COVID-19 patients and non-COVID-19 patients with non-intubated AHRF or ARDS.The reviews of this paper are available via the supplemental material section.


Subject(s)
COVID-19/complications , Patient Positioning , Respiratory Distress Syndrome/therapy , Respiratory Insufficiency/therapy , SARS-CoV-2 , COVID-19/mortality , Humans , Intubation, Intratracheal , Oxygen/blood , Prone Position , Respiration
17.
Sci China Technol Sci ; 64(4): 869-878, 2021.
Article in English | MEDLINE | ID: covidwho-1092731

ABSTRACT

Mechanical ventilation is an effective medical means in the treatment of patients with critically ill, COVID-19 and other pulmonary diseases. During the mechanical ventilation and the weaning process, the conduct of pulmonary rehabilitation is essential for the patients to improve the spontaneous breathing ability and to avoid the weakness of respiratory muscles and other pulmonary functional trauma. However, inappropriate mechanical ventilation strategies for pulmonary rehabilitation often result in weaning difficulties and other ventilator complications. In this article, the mechanical ventilation strategies for pulmonary rehabilitation are studied based on the analysis of patient-ventilator interaction. A pneumatic model of the mechanical ventilation system is established to determine the mathematical relationship among the pressure, the volumetric flow, and the tidal volume. Each ventilation cycle is divided into four phases according to the different respiratory characteristics of patients, namely, the triggering phase, the inhalation phase, the switching phase, and the exhalation phase. The control parameters of the ventilator are adjusted by analyzing the interaction between the patient and the ventilator at different phases. A novel fuzzy control method of the ventilator support pressure is proposed in the pressure support ventilation mode. According to the fuzzy rules in this research, the plateau pressure can be obtained by the trigger sensitivity and the patient's inspiratory effort. An experiment prototype of the ventilator is established to verify the accuracy of the pneumatic model and the validity of the mechanical ventilation strategies proposed in this article. In addition, through the discussion of the patient-ventilator asynchrony, the strategies for mechanical ventilation can be adjusted accordingly. The results of this research are meaningful for the clinical operation of mechanical ventilation. Besides, these results provide a theoretical basis for the future research on the intelligent control of ventilator and the automation of weaning process.

18.
World J Clin Cases ; 9(3): 528-539, 2021 Jan 26.
Article in English | MEDLINE | ID: covidwho-1069992

ABSTRACT

Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2, has posed a serious threat to global public health security. With the increase in the number of confirmed cases globally, the World Health Organization has declared the outbreak of COVID-19 an international public health emergency. Despite atypical pneumonia as the primary symptom, liver dysfunction has also been observed in many clinical cases and is associated with the mortality risk in patients with COVID-19, like severe acute respiratory syndrome and Middle East respiratory syndrome. Here we will provide a schematic overview of the clinical characteristics and the possible mechanisms of liver injury caused by severe acute respiratory syndrome coronavirus 2 infection, which may provide help for optimizing the management of liver injury and reducing mortality in COVID-19 patients.

20.
Complexity ; 2020, 2020.
Article in English | ProQuest Central | ID: covidwho-825970

ABSTRACT

The synchrony of patient-ventilator interaction affects the process of mechanical ventilation which is clinically applied for respiratory support. The occurrence of patient-ventilator asynchrony (PVA) not only increases the risk of ventilator complications but also affects the comfort of patients. To solve the problem of uncertain patient-ventilator interaction in the mechanical ventilation system, a novel method to evaluate patient-ventilator synchrony is proposed in this article. Firstly, a pneumatic model is established to simulate the mechanical ventilation system, which is verified to be accurate by the experiments. Then, the PVA phenomena are classified and detected based on the analysis of the ventilator waveforms. On this basis, a novel synchrony index SIhao is established to evaluate the patient-ventilator synchrony. It not only solves the defects of previous evaluation indexes but also can be used as the response parameter in the future research of ventilator control algorithms. The accurate evaluation of patient-ventilator synchrony can be applied to the adjustment of clinical strategies and the pathological analyses of patients. This research can also reduce the burden on clinicians and help to realize the adaptive control of the mechanical ventilation and weaning process in the future.

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