Your browser doesn't support javascript.
Show: 20 | 50 | 100
Results 1 - 20 de 23
Filter
1.
J Nanobiotechnology ; 21(1): 144, 2023 Apr 30.
Article in English | MEDLINE | ID: covidwho-20243437

ABSTRACT

Field-effect transistor (FET) is regarded as the most promising candidate for the next-generation biosensor, benefiting from the advantages of label-free, easy operation, low cost, easy integration, and direct detection of biomarkers in liquid environments. With the burgeoning advances in nanotechnology and biotechnology, researchers are trying to improve the sensitivity of FET biosensors and broaden their application scenarios from multiple strategies. In order to enable researchers to understand and apply FET biosensors deeply, focusing on the multidisciplinary technical details, the iteration and evolution of FET biosensors are reviewed from exploring the sensing mechanism in detecting biomolecules (research direction 1), the response signal type (research direction 2), the sensing performance optimization (research direction 3), and the integration strategy (research direction 4). Aiming at each research direction, forward perspectives and dialectical evaluations are summarized to enlighten rewarding investigations.


Subject(s)
Biosensing Techniques , Transistors, Electronic , Nanotechnology , Biosensing Techniques/methods
2.
Sci Total Environ ; 893: 164846, 2023 Oct 01.
Article in English | MEDLINE | ID: covidwho-20234062

ABSTRACT

The impact of the COVID-19 pandemic and related restrictions on alcohol consumption in Australia remains unclear. High-resolution daily samples from a wastewater treatment plant (WWTP) which served one of the largest cities in Australia, Melbourne, were analysed for temporal trends in alcohol consumption under extended periods of COVID-19 restrictions in 2020. Melbourne experienced two major lockdowns in 2020, which divided the year of 2020 into five periods (pre-lockdown, first lockdown, between lockdown, second lockdown and post second-lockdown). In this study, daily sampling identified shifts in alcohol consumption during different periods of restrictions. Alcohol consumption in the first lockdown period, when bars closed and social and sports events ceased, was lower than pre-lockdown period. However, alcohol consumption was higher in the second lockdown period than the previous lockdown period. There were spikes in alcohol consumption at the start and end of each lockdown (except for post lockdown). For most of 2020, the usual weekday-weekend variations in alcohol consumption were less evident but there was a significant difference in alcohol consumption between weekdays and weekends after the second lockdown. This suggests that drinking patterns eventually returned to normal after the end of the second lockdown. This study demonstrates the usefulness of high-resolution wastewater sampling in evaluating the effects on alcohol consumption of social interventions in specific temporal locations.


Subject(s)
COVID-19 , Wastewater , Humans , Pandemics , COVID-19/epidemiology , Communicable Disease Control , Alcohol Drinking/epidemiology , Australia/epidemiology
3.
Histol Histopathol ; : 18510, 2022 Sep 07.
Article in English | MEDLINE | ID: covidwho-2311664

ABSTRACT

The virus that causes COVID-19(Corona Virus Disease 2019), SARS-CoV-2(Severe Acute Respiratory Syndrome Coronavirus 2), is causing a worldwide pandemic, posing a substantial threat to human health. Patients show signs of pneumonia, ARDS, shock, acute cardiac injury, acute kidney injury and other complications. The SARS-CoV-2 receptor is angiotensin converting enzyme 2 (ACE2), which is an important component of the renin-angiotensin system (RAS). In addition, TMPRSS2 or other cofactors are needed to allow the virus to enter the host. Clinical patients have exhibited varying degrees of genitourinary and endocrine system damage, and some studies have also reported potential risks to the genitourinary and endocrine systems. This article reviews the mechanism underlying SARS-CoV-2 infection and the current studies on the male genitourinary and endocrine systems and proposes that more attention should be directed towards human reproductive and endocrine health during the SARS-CoV-2 epidemic.

4.
Atmospheric Measurement Techniques ; 16(8):2237-2262, 2023.
Article in English | ProQuest Central | ID: covidwho-2304944

ABSTRACT

Nitrogen dioxide (NO2) air pollution provides valuable information for quantifying NOx (NOx = NO + NO2) emissions and exposures. This study presents a comprehensive method to estimate average tropospheric NO2 emission strengths derived from 4-year (May 2018–June 2022) TROPOspheric Monitoring Instrument (TROPOMI) observations by combining a wind-assigned anomaly approach and a machine learning (ML) method, the so-called gradient descent algorithm. This combined approach is firstly applied to the Saudi Arabian capital city of Riyadh, as a test site, and yields a total emission rate of 1.09×1026 molec. s-1. The ML-trained anomalies fit very well with the wind-assigned anomalies, with an R2 value of 1.0 and a slope of 0.99. Hotspots of NO2 emissions are apparent at several sites: over a cement plant and power plants as well as over areas along highways. Using the same approach, an emission rate of 1.99×1025 molec. s-1 is estimated in the Madrid metropolitan area, Spain. Both the estimate and spatial pattern are comparable with the Copernicus Atmosphere Monitoring Service (CAMS) inventory.Weekly variations in NO2 emission are highly related to anthropogenic activities, such as the transport sector. The NO2 emissions were reduced by 16 % at weekends in Riyadh, and high reductions were found near the city center and in areas along the highway. An average weekend reduction estimate of 28 % was found in Madrid. The regions with dominant sources are located in the east of Madrid, where residential areas and the Madrid-Barajas airport are located. Additionally, due to the COVID-19 lockdowns, the NO2 emissions decreased by 21 % in March–June 2020 in Riyadh compared with the same period in 2019. A much higher reduction (62 %) is estimated for Madrid, where a very strict lockdown policy was implemented. The high emission strengths during lockdown only persist in the residential areas, and they cover smaller areas on weekdays compared with weekends. The spatial patterns of NO2 emission strengths during lockdown are similar to those observed at weekends in both cities. Although our analysis is limited to two cities as test examples, the method has proven to provide reliable and consistent results. It is expected to be suitable for other trace gases and other target regions. However, it might become challenging in some areas with complicated emission sources and topography, and specific NO2 decay times in different regions and seasons should be taken into account. These impacting factors should be considered in the future model to further reduce the uncertainty budget.

5.
Biosens Bioelectron ; 222: 114979, 2022 Nov 30.
Article in English | MEDLINE | ID: covidwho-2236005

ABSTRACT

False detection of SARS-CoV-2 is detrimental to epidemic prevention and control. The scalar nature of the detected signal and the imperfect target recognition property of developed methods are the root causes of generating false signals. Here, we reported a collaborative system of CRISPR-Cas13a coupling with the stabilized graphene field-effect transistor, providing high-intensity vector signals for detecting SARS-CoV-2. In this collaborative system, SARS-CoV-2 RNA generates a "big subtraction" signal with a right-shifted feature, whereas any untargets cause the left-shifted characteristic signal. Thus, the false detection of SARS-CoV-2 is eliminated. High sensitivity with 0.15 copies/µL was obtained. In addition, the wide concerned instability of the graphene field-effect transistor for biosensing in solution environment was solved by the hydrophobic treatment to its substrate, which should be a milestone in advancing it's engineering application. This collaborative system characterized by the high-intensity vector signal and amazing stability significantly advances the accurate SARS-CoV-2 detection from the aspect of signal nature.

7.
Biosensors & bioelectronics ; 2022.
Article in English | EuropePMC | ID: covidwho-2126062

ABSTRACT

False detection of SARS-CoV-2 is detrimental to epidemic prevention and control. The scalar nature of the detected signal and the imperfect target recognition property of developed methods are the root causes of generating false signals. Here, we reported a collaborative system of CRISPR-Cas13a coupling with the stabilized graphene field-effect transistor, providing high-intensity vector signals for detecting SARS-CoV-2. In this collaborative system, SARS-CoV-2 RNA generates a “big subtraction” signal with a right-shifted feature, whereas any untargets cause the left-shifted characteristic signal. Thus, the false detection of SARS-CoV-2 is eliminated. High sensitivity with 0.15 copies/μL was obtained. In addition, the wide concerned instability of the graphene field-effect transistor for biosensing in solution environment was solved by the hydrophobic treatment to its substrate, which should be a milestone in advancing it's engineering application. This collaborative system characterized by the high-intensity vector signal and amazing stability significantly advances the accurate SARS-CoV-2 detection from the aspect of signal nature.

9.
Modern Physics Letters B ; : 1, 2022.
Article in English | Academic Search Complete | ID: covidwho-1891917

ABSTRACT

Many scientific research papers report that jet-like flow during speech is a potent route for viral transmission in the COVID-19 pandemic. Droplet emission occurs during breaking, speaking, singing, coughing and sneezing, which could be affected by the shear-thinning rheology of the liquid. Here we test the viscosity of simple liquid system in many-body dissipative particle dynamics model under different driven forces, which illustrates that the simple liquid system interestingly has shear-thinning property. Based on this, we simulate the process of jet-like flow and capture the rupture of liquid cylinder and the process of drop generation, which implies the jet-induced liquid pinchoff and drop generation can be regulated by initial driven force and its temperature. The results show that larger pressure pulse could generate longer liquid cylinder and larger drops, as well as at lower force frequency. This work can provide an insight in liquid jet-like flow with shear-thining property and yield a better understanding of virus spreading via salivary droplets. [ FROM AUTHOR] Copyright of Modern Physics Letters B is the property of World Scientific Publishing Company and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full . (Copyright applies to all s.)

11.
Disease Surveillance ; 37(2):269-274, 2022.
Article in Chinese | GIM | ID: covidwho-1855879

ABSTRACT

Objective: To understand the mental health status and its influential factors of staff of Chinese enterprises in Ethiopia.

12.
Front Med (Lausanne) ; 8: 628370, 2021.
Article in English | MEDLINE | ID: covidwho-1581312

ABSTRACT

The outbreak of coronavirus disease 2019 (COVID-19) has been spreading rapidly in China and the Chinese government took a series of policies to control the epidemic. Studies found that severe COVID-19 is characterized by pneumonia, lymphopenia, exhausted lymphocytes and a cytokine storm. Studies have showen that SARS-CoV2 has significant genomic similarity to the severe acute respiratory syndrome (SARS-CoV), which was a pandemic in 2002. More importantly, some diligent measures were used to limit its spread according to the evidence of hospital spread. Therefore, the Public Health Emergency of International Concern (PHEIC) has been established by the World Health Organization (WHO) with strategic objectives for public health to curtail its impact on global health and economy. The purpose of this paper is to review the transmission patterns of the three pneumonia: SARS-CoV2, SARS-CoV, and MERS-CoV. We compare the new characteristics of COVID-19 with those of SARS-CoV and MERS-CoV.

13.
China CDC Wkly ; 2(21): 365-369, 2020 May 22.
Article in English | MEDLINE | ID: covidwho-1449636

ABSTRACT

WHAT IS ALREADY KNOWN ABOUT THIS TOPIC?: Since the first COVID-19 confirmed case was reported, the current epidemic in Africa has rapidly increased. WHAT IS ADDED BY THIS REPORT?: As of April 4, 2020, a total of 7,405 confirmed cases and 305 deaths had been reported from 51 countries across Africa. The cumulative number of reported COVID-19 cases varied among the five regions of Africa, of which northern Africa reported the largest number of confirmed cases. The five countries with the highest number of cases are South Africa, Algeria, Egypt, Morocco, and Tunisia. WHAT ARE THE IMPLICATIONS FOR PUBLIC HEALTH PRACTICE?: Early detection, early isolation, early reporting, and early treatment of the COVID-19 are important and critical measures for the successful control of further transmission of COVID-19. Now more stringent prevention and control measures have been implemented in Africa, but due to often insufficient basic medical facilities and medical services, Africa is still facing challenges to the pandemic and needs to strengthen national health systems and develop immediate and future health plans.

14.
Front Psychol ; 12: 619303, 2021.
Article in English | MEDLINE | ID: covidwho-1394801

ABSTRACT

Even though the coronavirus disease (COVID-19) has limited consumption, individuals continue to plan post-pandemic consumption activities to get rid of the stress caused by consumption repression. Building on Maslow's theory of needs and Herzberg's two-factor theory, our research categorizes consumption into fundamental ("must-have" products that fulfill the physical needs of individuals), hygiene (maintaining the security needs of consumers), and motivational consumption (enhancing well-being of individuals). Based on empirical data of purchase behavior and consumption expectation before, during, and after the pandemic in China, we identify how consumption repression induces psychological distress, via a sense of feeling threatened, lacking control, or lacking freedom, and how the expectation of future consumption alleviates that stress. Results show that fundamental consumption leads to psychological distress; hygiene consumption can both result in and reduce stress; and motivational consumption can reduce stress. Our findings provide new insights into the relationship between consumption and psychological distress through new theoretical formulations. The results can be applied by marketers attempting to understand purchase decision-making and by policymakers supporting both citizens and commerce during social emergencies.

15.
Cell Discov ; 7(1): 42, 2021 Jun 08.
Article in English | MEDLINE | ID: covidwho-1261993

ABSTRACT

The pathophysiology of coronavirus disease 19 (COVID-19) involves a multitude of host responses, yet how they unfold during the course of disease progression remains unclear. Here, through integrative analysis of clinical laboratory tests, targeted proteomes, and transcriptomes of 963 patients in Shanghai, we delineate the dynamics of multiple circulatory factors within the first 30 days post-illness onset and during convalescence. We show that hypercortisolemia represents one of the probable causes of acute lymphocytopenia at the onset of severe/critical conditions. Comparison of the transcriptomes of the bronchoalveolar microenvironment and peripheral blood indicates alveolar macrophages, alveolar epithelial cells, and monocytes in lungs as the potential main sources of elevated cytokines mediating systemic immune responses and organ damages. In addition, the transcriptomes of patient blood cells are characterized by distinct gene regulatory networks and alternative splicing events. Our study provides a panorama of the host responses in COVID-19, which may serve as the basis for developing further diagnostics and therapy.

16.
Influenza Other Respir Viruses ; 15(3): 331-335, 2021 05.
Article in English | MEDLINE | ID: covidwho-1119238

ABSTRACT

Evaluation of population-based COVID-19 control measures informs strategies to quell the current pandemic and reduce the impact of those yet to come. Effective COVID-19 control measures may simultaneously reduce the incidence of other acute respiratory infections (ARIs) due to shared transmission modalities. To assess the impact of stay-at-home orders and other physical distancing measures on the prevalence of ARI-related symptoms, we compared symptoms reported by prospective college cohorts enrolled during two consecutive academic years. ARI-related symptoms declined following campus closure and implementation of stay-at-home orders, demonstrating the impact of population-based physical distancing measures on control of a broad range of respiratory infections.


Subject(s)
COVID-19/prevention & control , Respiratory Tract Infections/epidemiology , SARS-CoV-2 , Acute Disease , Adolescent , Adult , Cohort Studies , Female , Humans , Male , Physical Distancing , Prevalence , Young Adult
17.
Cell ; 184(3): 775-791.e14, 2021 02 04.
Article in English | MEDLINE | ID: covidwho-1014394

ABSTRACT

The molecular pathology of multi-organ injuries in COVID-19 patients remains unclear, preventing effective therapeutics development. Here, we report a proteomic analysis of 144 autopsy samples from seven organs in 19 COVID-19 patients. We quantified 11,394 proteins in these samples, in which 5,336 were perturbed in the COVID-19 patients compared to controls. Our data showed that cathepsin L1, rather than ACE2, was significantly upregulated in the lung from the COVID-19 patients. Systemic hyperinflammation and dysregulation of glucose and fatty acid metabolism were detected in multiple organs. We also observed dysregulation of key factors involved in hypoxia, angiogenesis, blood coagulation, and fibrosis in multiple organs from the COVID-19 patients. Evidence for testicular injuries includes reduced Leydig cells, suppressed cholesterol biosynthesis, and sperm mobility. In summary, this study depicts a multi-organ proteomic landscape of COVID-19 autopsies that furthers our understanding of the biological basis of COVID-19 pathology.


Subject(s)
COVID-19/metabolism , Gene Expression Regulation , Proteome/biosynthesis , Proteomics , SARS-CoV-2/metabolism , Autopsy , COVID-19/pathology , COVID-19/therapy , Female , Humans , Male , Organ Specificity
18.
Nat Commun ; 11(1): 5752, 2020 11 13.
Article in English | MEDLINE | ID: covidwho-926678

ABSTRACT

Efficacious interventions are urgently needed for the treatment of COVID-19. Here, we report a monoclonal antibody (mAb), MW05, with SARS-CoV-2 neutralizing activity by disrupting the interaction of receptor binding domain (RBD) with angiotensin-converting enzyme 2 (ACE2) receptor. Crosslinking of Fc with FcγRIIB mediates antibody-dependent enhancement (ADE) activity by MW05. This activity is eliminated by introducing the LALA mutation to the Fc region (MW05/LALA). Potent prophylactic and therapeutic effects against SARS-CoV-2 are observed in rhesus monkeys. A single dose of MW05/LALA blocks infection of SARS-CoV-2 in prophylactic treatment and clears SARS-CoV-2 in three days in a therapeutic treatment setting. These results pave the way for the development of MW05/LALA as an antiviral strategy for COVID-19.


Subject(s)
Antibodies, Monoclonal/immunology , Antibodies, Neutralizing/immunology , Antiviral Agents/pharmacology , Betacoronavirus/immunology , Coronavirus Infections/therapy , Pneumonia, Viral/therapy , Spike Glycoprotein, Coronavirus/immunology , Angiotensin-Converting Enzyme 2 , Animals , Antibodies, Viral/immunology , COVID-19 , Cell Line , Chlorocebus aethiops , Coronavirus Infections/prevention & control , Female , HEK293 Cells , Humans , Macaca mulatta , Male , Pandemics/prevention & control , Peptidyl-Dipeptidase A/metabolism , Pneumonia, Viral/prevention & control , Receptors, IgG/genetics , Receptors, IgG/immunology , Receptors, Virus/metabolism , SARS-CoV-2 , Vero Cells , Virus Attachment
19.
EBioMedicine ; 61: 103036, 2020 Nov.
Article in English | MEDLINE | ID: covidwho-844322

ABSTRACT

BACKGROUND: Real-time reverse transcription-PCR (rRT-PCR) has been the most effective and widely implemented diagnostic technology since the beginning of the COVID-19 pandemic. However, fuzzy rRT-PCR readouts with high Ct values are frequently encountered, resulting in uncertainty in diagnosis. METHODS: A Specific Enhancer for PCR-amplified Nucleic Acid (SENA) was developed based on the Cas12a trans-cleavage activity, which is specifically triggered by the rRT-PCR amplicons of the SARS-CoV-2 Orf1ab (O) and N fragments. SENA was first characterized to determine its sensitivity and specificity, using a systematic titration experiment with pure SARS-CoV-2 RNA standards, and was then verified in several hospitals, employing a couple of commercial rRT-PCR kits and testing various clinical specimens under different scenarios. FINDINGS: The ratio (10 min/5 min) of fluorescence change (FC) with mixed SENA reaction (mix-FCratio) was defined for quantitative analysis of target O and N genes, and the Limit of Detection (LoD) of mix-FCratio with 95% confidence interval was 1.2≤1.6≤2.1. Totally, 295 clinical specimens were analyzed, among which 21 uncertain rRT-PCR cases as well as 4 false negative and 2 false positive samples were characterized by SENA and further verified by next-generation sequencing (NGS). The cut-off values for mix-FCratio were determined as 1.145 for positive and 1.068 for negative. INTERPRETATION: SENA increases both the sensitivity and the specificity of rRT-PCR, solving the uncertainty problem in COVID-19 diagnosis and thus providing a simple and low-cost companion diagnosis for combating the pandemic. FUNDING: Detailed funding information is available at the end of the manuscript.


Subject(s)
Bacterial Proteins/metabolism , Betacoronavirus/genetics , CRISPR-Associated Proteins/metabolism , Clustered Regularly Interspaced Short Palindromic Repeats/genetics , Endodeoxyribonucleases/metabolism , RNA, Viral/metabolism , Real-Time Polymerase Chain Reaction/methods , Betacoronavirus/isolation & purification , COVID-19 , Coronavirus Infections/diagnosis , Coronavirus Infections/pathology , Coronavirus Infections/virology , Coronavirus Nucleocapsid Proteins , Humans , Limit of Detection , Nasal Cavity/virology , Nucleic Acid Amplification Techniques/methods , Nucleic Acid Amplification Techniques/standards , Nucleocapsid Proteins/genetics , Nucleocapsid Proteins/metabolism , Pandemics , Phosphoproteins , Pneumonia, Viral/diagnosis , Pneumonia, Viral/pathology , Pneumonia, Viral/virology , Polyproteins , RNA, Viral/genetics , Real-Time Polymerase Chain Reaction/standards , Reference Standards , SARS-CoV-2 , Viral Proteins/genetics , Viral Proteins/metabolism
20.
Histopathology ; 78(4): 542-555, 2021 Mar.
Article in English | MEDLINE | ID: covidwho-756976

ABSTRACT

AIMS: Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), infection has been deemed as a global pandemic by the World Health Organisation. While diffuse alveolar damage (DAD) is recognised to be the primary manifestation of COVID-19 pneumonia, there has been little emphasis on the progression to the fibrosing phase of DAD. This topic is of great interest, due to growing concerns regarding the potential long-term complications in prolonged survivors. METHODS AND RESULTS: Here we report a detailed histopathological study of 30 autopsy cases with COVID-19 virus infection, based on minimally invasive autopsies performed between February and March, 2020. The mean age was 69 years, with 20 (67%) males and 10 (33%) females and frequent (70.0%) underlying comorbidities. The duration of illness ranged from 16 to 82 (median = 42) days. Histologically, the most common manifestation was diffuse alveolar damage (DAD) in 28 (93.3%) cases which showed predominantly acute (32%), organising (25%) and/or fibrosing (43%) patterns. Patients with fibrosing DAD were one decade younger (P = 0.034) and they had a longer duration of illness (P = 0.033), hospitalisation (P = 0.037) and mechanical ventilation (P = 0.014) compared to those with acute DAD. Patients with organising DAD had a longer duration of illness (P = 0.032) and hospitalisation (P = 0.023) compared to those with acute DAD. CONCLUSIONS: COVID-19 pneumonia patients who develop DAD can progress to the fibrosing pattern. While we observed fibrosing DAD in fatal cases, whether or not surviving patients are at risk for developing pulmonary fibrosis and the frequency of this complication will require further clinical and radiological follow-up studies.


Subject(s)
COVID-19/complications , Pandemics , Pneumonia/etiology , Pulmonary Fibrosis/etiology , SARS-CoV-2/physiology , Adult , Aged , Aged, 80 and over , Autopsy , COVID-19/pathology , COVID-19/virology , China/epidemiology , Disease Progression , Female , Humans , Male , Middle Aged , Pneumonia/pathology , Pneumonia/virology , Pulmonary Fibrosis/pathology , Pulmonary Fibrosis/virology
SELECTION OF CITATIONS
SEARCH DETAIL