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1.
Chem Biodivers ; 18(11): e2100674, 2021 Nov.
Article in English | MEDLINE | ID: covidwho-1615945

ABSTRACT

Chemical investigation on a Streptomyces sp. strain MS180069 isolated from a sediment sample collected from the South China Sea, yielded the new benzo[f]isoindole-dione alkaloid, bhimamycin J (1). The structure was determined by extensive spectroscopic analysis, including HRMS, 1D, 2D NMR, and X-ray diffraction techniques. A molecular docking study revealed 1 as a new molecular motif that binds with human angiotensin converting enzyme2 (ACE2), recently described as the cell surface receptor responsible for uptake of 2019-CoV-2. Using enzyme assays we confirm that 1 inhibits human ACE2 79.7 % at 25 µg/mL.


Subject(s)
Alkaloids/chemistry , Geologic Sediments/microbiology , Isoindoles/chemistry , Streptomyces/chemistry , Alkaloids/metabolism , Alkaloids/pharmacology , Alkaloids/therapeutic use , Angiotensin-Converting Enzyme 2/antagonists & inhibitors , Angiotensin-Converting Enzyme 2/metabolism , Binding Sites , COVID-19/drug therapy , COVID-19/virology , Fungi/drug effects , Gram-Negative Bacteria/drug effects , Gram-Positive Bacteria/drug effects , Humans , Isoindoles/isolation & purification , Isoindoles/metabolism , Isoindoles/pharmacology , Magnetic Resonance Spectroscopy , Molecular Conformation , Molecular Docking Simulation , SARS-CoV-2/isolation & purification , Streptomyces/isolation & purification , Streptomyces/metabolism
2.
BMC Endocr Disord ; 22(1): 13, 2022 Jan 06.
Article in English | MEDLINE | ID: covidwho-1613234

ABSTRACT

BACKGROUND: Research regarding the association between severe obesity and in-hospital mortality is inconsistent. We evaluated the impact of body mass index (BMI) levels on mortality in the medical wards. The analysis was performed separately before and during the COVID-19 pandemic. METHODS: We retrospectively retrieved data of adult patients admitted to the medical wards at the Mount Sinai Health System in New York City. The study was conducted between January 1, 2011, to March 23, 2021. Patients were divided into two sub-cohorts: pre-COVID-19 and during-COVID-19. Patients were then clustered into groups based on BMI ranges. A multivariate logistic regression analysis compared the mortality rate among the BMI groups, before and during the pandemic. RESULTS: Overall, 179,288 patients were admitted to the medical wards and had a recorded BMI measurement. 149,098 were admitted before the COVID-19 pandemic and 30,190 during the pandemic. Pre-pandemic, multivariate analysis showed a "J curve" between BMI and mortality. Severe obesity (BMI > 40) had an aOR of 0.8 (95% CI:0.7-1.0, p = 0.018) compared to the normal BMI group. In contrast, during the pandemic, the analysis showed a "U curve" between BMI and mortality. Severe obesity had an aOR of 1.7 (95% CI:1.3-2.4, p < 0.001) compared to the normal BMI group. CONCLUSIONS: Medical ward patients with severe obesity have a lower risk for mortality compared to patients with normal BMI. However, this does not apply during COVID-19, where obesity was a leading risk factor for mortality in the medical wards. It is important for the internal medicine physician to understand the intricacies of the association between obesity and medical ward mortality.


Subject(s)
Body Mass Index , COVID-19/mortality , Hospital Mortality/trends , Hospitalization/statistics & numerical data , Obesity/physiopathology , SARS-CoV-2/isolation & purification , Aged , COVID-19/epidemiology , COVID-19/pathology , COVID-19/virology , Case-Control Studies , Female , Humans , Male , Middle Aged , New York City/epidemiology , Prognosis , Retrospective Studies , Risk Factors , Survival Rate
3.
Cancer Prev Res (Phila) ; 15(1): 1-2, 2022 01.
Article in English | MEDLINE | ID: covidwho-1613126

ABSTRACT

The First Lady of the United States, Dr. Jill Biden, visited the Hollings Cancer Center at the Medical University of South Carolina on October 25, 2021. This Commentary remarks on the administration's goal of directing public attention to cancer screening and prevention as part of an overall effort to recover ground lost in the COVID-19 pandemic, particularly in underserved communities.


Subject(s)
COVID-19/complications , Early Detection of Cancer/methods , Early Detection of Cancer/standards , Famous Persons , Neoplasms/diagnosis , SARS-CoV-2/isolation & purification , COVID-19/virology , Humans , Neoplasms/epidemiology , Neoplasms/prevention & control , Neoplasms/virology , United States
5.
PLoS One ; 16(3): e0249214, 2021.
Article in English | MEDLINE | ID: covidwho-1605662

ABSTRACT

The novel coronavirus (COVID-19) is an infectious disease caused by a newly discovered coronavirus. Despite strong efforts that have been taking place to control the pandemic globally, the virus is on the rise in many countries. Hence, this study assessed the maternal health care services utilization amidst the COVID-19 pandemic in West Shoa zone, Central Ethiopia. A community-based cross-sectional study was conducted among 844 pregnant women or those who gave birth in the last 6 months before the study. A multi-stage sampling technique was used to select the study participants. The data were collected through face-to-face interviews using a semi-structured questionnaire. Logistic regressions were performed to identify the presence of significant associations, and an adjusted odds ratio with 95%CI was employed for the strength and directions of association between the independent and outcome variables. A P-value of <0.05 was used to declare statistical significance. The prevalence of maternal health service utilization during the COVID-19 pandemic was 64.8%. The odds of maternal health service utilization was higher among mothers who had primary (AOR = 2.16, 95%CI: 1.29-3.60), secondary (AOR = 1.97, 95%CI: 1.13-3.44), and college and above education (AOR = 2.89, 95%CI: 1.34-6.22) than those who could not read and write. Besides, mothers who did travel 30-60 minutes (AOR = 0.37, 95%CI: 0.23-0.59) and 60-90minutes (AOR = 0.10, 95%CI: 0.05-0.19) to reach the health facility had a lower odds of maternal health service utilization than those who did travel <30 minutes. Moreover, mothers who earn 1000-2000 (AOR = 3.10, 95%CI: 1.73-5.55) and > 2000 birrs (AOR = 2.66 95%CI: 1.52-4.64) had higher odds of maternal health service utilization than those who earn <500 birrs. Similarly, the odds of utilizing maternal health service were higher among mothers who did not fear COVID-19 infection (AOR = 2.79, 95%CI: 1.85-4.20), who had not had to request permission from husband to visit the health facility (AOR = 7.24, 95%CI: 2.65-19.75), who had practicedCOVID-19 prevention measure (AOR = 5.82, 95%CI: 3.87-8.75), and used face mask (AOR = 2.06, 95% CI: 1.28-3.31) than their counterpart. Empowering mothers and creating awareness on COVID-19 preventionis recommended to improve maternal health service utilization during the COVID-19 pandemic.


Subject(s)
COVID-19/pathology , Health Facilities/statistics & numerical data , Maternal Health Services/statistics & numerical data , Adolescent , Adult , COVID-19/epidemiology , COVID-19/virology , Cross-Sectional Studies , Educational Status , Ethiopia/epidemiology , Female , Humans , Logistic Models , Masks , Odds Ratio , Pandemics , Pregnancy , SARS-CoV-2/isolation & purification , Social Class , Young Adult
6.
PLoS One ; 16(3): e0247797, 2021.
Article in English | MEDLINE | ID: covidwho-1605332

ABSTRACT

Since the initial identification of the novel coronavirus SARS-CoV-2 in December of 2019, researchers have raced to understand its pathogenesis and begun devising vaccine and treatment strategies. An accurate understanding of the body's temporal immune response against SARS-CoV-2 is paramount to successful vaccine development and disease progression monitoring. To provide insight into the antibody response against SARS-CoV-2, plasma samples from 181 PCR-confirmed COVID-19 patients collected at various timepoints post-symptom onset (PSO) were tested for the presence of anti-SARS-CoV-2 IgM and IgG antibodies via lateral flow. Additionally, 21 donors were tracked over time to elucidate patient-specific immune responses. We found sustained levels of anti-SARS-CoV-2 antibodies past 130 days PSO, with 99% positivity observed at 31-60 days PSO. By 61-90 days PSO, the percentage of IgM-/IgG+ results were nearly equal to that of IgM+/IgG+ results, demonstrating a shift in the immune response with a decrease in IgM antibody levels. Results from this study not only provide evidence that the antibody response to COVID-19 can persist for over 4 months, but also demonstrates the ability of Easy Check™ to monitor seroconversion and antibody response of patients. Easy Check was sufficiently sensitive to detect antibodies in patient samples as early as 1-4 days PSO with 86% positivity observed at 5-7 days PSO. Further studies are required to determine the longevity and efficacy of anti-SARS-CoV-2 antibodies, and whether they are protective against re-infection.


Subject(s)
Antibodies, Viral/blood , COVID-19/blood , Immunoglobulin G/blood , Immunoglobulin M/blood , SARS-CoV-2/immunology , Adolescent , Adult , Aged , Aged, 80 and over , Antibodies, Viral/immunology , COVID-19/immunology , COVID-19 Serological Testing/instrumentation , COVID-19 Serological Testing/methods , Equipment Design , Female , Humans , Immunoglobulin G/immunology , Immunoglobulin M/immunology , Longitudinal Studies , Male , Middle Aged , SARS-CoV-2/isolation & purification , Young Adult
7.
PLoS One ; 16(5): e0251410, 2021.
Article in English | MEDLINE | ID: covidwho-1604261

ABSTRACT

The objective of this study was to explore the impact of the coronavirus disease 2019 epidemic on ongoing and upcoming drug clinical trials. Qualitative semi-structured interviews were conducted with clinical trial staff and clinical trial subjects were surveyed by questionnaire in this study. The results of interviews and questionnaire showed that coronavirus disease 2019 pandemic has led to many changes in the implementation of drug clinical trials, including: a variety of meetings being held online webinars using various platforms, telemedicine and follow-up by video, A large number of deviations from protocol and losses of follow-up, delivery of clinical trial drugs by express, additional workload caused by screening for coronavirus, and anxiety of subjects. These results suggest that the coronavirus disease 2019 outbreak has hindered the progress and damaged the quality of clinical trials. The online meeting, remote follow-up, express delivery of drugs and remote monitoring in the epidemic environment can ensure the progress of clinical trials to a certain extent, but they cannot fully guarantee the quality as before.


Subject(s)
COVID-19/pathology , Clinical Trials as Topic , Adult , Antiviral Agents/therapeutic use , Anxiety/etiology , COVID-19/drug therapy , COVID-19/epidemiology , COVID-19/virology , Humans , Interviews as Topic , Middle Aged , Pandemics , Patients/psychology , Research Personnel/psychology , SARS-CoV-2/isolation & purification , Surveys and Questionnaires , Telemedicine , Young Adult
8.
Mikrochim Acta ; 188(10): 316, 2021 Sep 02.
Article in English | MEDLINE | ID: covidwho-1604245

ABSTRACT

A novel label-free surface plasmon resonance (SPR) aptasensor has been constructed for the detection of N-gene of SARS-CoV-2 by using thiol-modified niobium carbide MXene quantum dots (Nb2C-SH QDs) as the bioplatform for anchoring N-gene-targeted aptamer. In the presence of SARS-CoV-2 N-gene, the immobilized aptamer strands changed their conformation to specifically bind with N-gene. It thus increased the contact area or enlarged the distance between aptamer and the SPR chip, resulting in a change of the SPR signal irradiated by the laser (He-Ne) with the wavelength (λ) of 633 nm. Nb2C QDs were derived from Nb2C MXene nanosheets via a solvothermal method, followed by functionalization with octadecanethiol through a self-assembling method. Subsequently, the gold chip for SPR measurements was modified with Nb2C-SH QDs via covalent binding of the Au-S bond also by self-assembling interaction. Nb2C-SH QDs not only resulted in high bioaffinity toward aptamer but also enhanced the SPR response. Thus, the Nb2C-SH QD-based SPR aptasensor had low limit of detection (LOD) of 4.9 pg mL-1 toward N-gene within the concentration range 0.05 to 100 ng mL-1. The sensor also showed excellent selectivity in the presence of various respiratory viruses and proteins in human serum and high stability. Moreover, the Nb2C-SH QD-based SPR aptasensor displayed a vast practical application for the qualitative analysis of N-gene from different samples, including seawater, seafood, and human serum. Thus, this work can provide a deep insight into the construction of the aptasensor for detecting SARS-CoV-2 in complex environments. A novel label-free surface plasmon resonance aptasensor has been constructed to detect sensitively and selectively the N-gene of SARS-CoV-2 by using thiol-modified niobium carbide MXene quantum dots as the scaffold to anchor the N-gene-targeted aptamer.


Subject(s)
Aptamers, Nucleotide , COVID-19/diagnosis , Niobium/chemistry , Nucleocapsid/metabolism , Quantum Dots/chemistry , SARS-CoV-2/isolation & purification , Surface Plasmon Resonance/methods , COVID-19/virology , Humans , Limit of Detection
9.
J Nanobiotechnology ; 20(1): 6, 2022 Jan 04.
Article in English | MEDLINE | ID: covidwho-1608546

ABSTRACT

BACKGROUND: Gold nanoparticles (AuNPs) have been widely used in local surface plasmon resonance (LSPR) immunoassays for biomolecule sensing, which is primarily based on two conventional methods: absorption spectra analysis and colorimetry. The low figure of merit (FoM) of the LSPR and high-concentration AuNP requirement restrict their limit of detection (LOD), which is approximately ng to µg mL-1 in antibody detection if there is no other signal or analyte amplification. Improvements in sensitivity have been slow in recent for a long time, and pushing the boundary of the current LOD is a great challenge of current LSPR immunoassays in biosensing. RESULTS: In this work, we developed spectral image contrast-based flow digital nanoplasmon-metry (Flow DiNM) to push the LOD boundary. Comparing the scattering image brightness of AuNPs in two neighboring wavelength bands near the LSPR peak, the peak shift signal is strongly amplified and quickly detected. Introducing digital analysis, the Flow DiNM provides an ultrahigh signal-to-noise ratio and has a lower sample volume requirement. Compared to the conventional analog LSPR immunoassay, Flow DiNM for anti-BSA detection in pure samples has an LOD as low as 1 pg mL-1 within only a 15-min detection time and 500 µL sample volume. Antibody assays against spike proteins of SARS-CoV-2 in artificial saliva that contained various proteins were also conducted to validate the detection of Flow DiNM in complicated samples. Flow DiNM shows significant discrimination in detection with an LOD of 10 pg mL-1 and a broad dynamic detection range of five orders of magnitude. CONCLUSION: Together with the quick readout time and simple operation, this work clearly demonstrated the high sensitivity and selectivity of the developed Flow DiNM in rapid antibody detection. Spectral image contrast and digital analysis further provide a new generation of LSPR immunoassay with AuNPs.


Subject(s)
COVID-19 Serological Testing/methods , COVID-19/diagnosis , SARS-CoV-2/isolation & purification , Surface Plasmon Resonance/methods , Antibodies, Viral/immunology , COVID-19/immunology , COVID-19 Serological Testing/instrumentation , Equipment Design , Gold/chemistry , Humans , Immunoassay/instrumentation , Immunoassay/methods , Metal Nanoparticles/chemistry , SARS-CoV-2/immunology , Saliva/virology , Spike Glycoprotein, Coronavirus/immunology , Surface Plasmon Resonance/instrumentation
11.
Eur Rev Med Pharmacol Sci ; 25(24): 8019-8022, 2021 12.
Article in English | MEDLINE | ID: covidwho-1605687

ABSTRACT

Recently a new variant of SARS-CoV-2 was reported from South Africa. World Health Organization (WHO) named this mutant as a variant of concern - Omicron (B.1.1.529) on 26th November 2021. This variant exhibited more than thirty amino acid mutations in the spike protein. This mutation rate is exceeding the other variants by approximately 5-11 times in the receptor-binding motif of the spike protein. Omicron (B.1.1.529) variant might have enhanced transmissibility and immune evasion. This new variant can reinfect individuals previously infected with other SARS-CoV-2 variants. Scientists expressed their concern about the efficacy of already existing COVID-19 vaccines against Omicron (B.1.1.529) infections. Some of the crucial mutations that are detected in the receptor-binding domain of the Omicron variant have been shared by previously evolved SARS-CoV-2 variants. Based on the Omicron mutation profile in the receptor-binding domain and motif, it might have collectively enhanced or intermediary infectivity relative to its previous variants. Due to extensive mutations in the spike protein, the Omicron variant might evade the immunity in the vaccinated individuals.


Subject(s)
COVID-19/epidemiology , Reinfection/epidemiology , SARS-CoV-2/pathogenicity , Spike Glycoprotein, Coronavirus/genetics , COVID-19/immunology , COVID-19/transmission , COVID-19/virology , COVID-19 Vaccines/genetics , COVID-19 Vaccines/immunology , COVID-19 Vaccines/therapeutic use , Humans , Immune Evasion/genetics , Immunogenicity, Vaccine , Mutation , Reinfection/immunology , Reinfection/transmission , Reinfection/virology , SARS-CoV-2/genetics , SARS-CoV-2/immunology , SARS-CoV-2/isolation & purification , Vaccine Potency
12.
Crit Care ; 26(1): 10, 2022 01 04.
Article in English | MEDLINE | ID: covidwho-1604921

ABSTRACT

BACKGROUND: Research on the duration of infectivity of ICU patients with COVID-19 has been sparse. Tests based on Reverse Transcriptase polymerase chain reaction (RT-PCR) detect both live virus and non-infectious viral RNA. We aimed to determine the duration of infectiousness based on viral culture of nasopharyngeal samples of patients with COVID-19. METHODS: Prospective observational study in adult intensive care units with a diagnosis of COVID-19 Pneumonia. Patients had repeated nasopharyngeal sampling performed after day 10 of ICU admission. Culture positive rate (based on viral culture on Vero cells in a level 4 lab) and Cycle threshold from RT-PCR were measured. RESULTS: Nine patients of the 108 samples (8.3%, 95% CI 3.9-15.2%) grew live virus at a median of 13 days (interquartile range 11-19) after their initial positive test. 74.1% of patients were RT-PCR positive but culture negative, and the remaining (17.6%) were RT-PCR and culture negative. Cycle threshold showed excellent ability to predict the presence of live virus, with a Ct < 25 with an AUC of 0.90 (95% CI 0.83-0.97, p < 0.001). The specificity of a Ct > 25 to predict negative viral culture was 100% (95% CI 70-100%). CONCLUSION: 8.3% of our ICU patients with COVID-19 grew live virus at a median of 13 days post-initial positive RT-PCR test. Severity of illness, use of mechanical ventilation, and time between tests did not predict the presence of live virus. Cycle threshold of > 25 had the best ability to determine the lack of live virus in these patents.


Subject(s)
COVID-19 , SARS-CoV-2 , Adult , COVID-19/therapy , COVID-19/virology , COVID-19 Nucleic Acid Testing , Critical Illness , Humans , Intensive Care Units , Nasopharynx/virology , Prospective Studies , SARS-CoV-2/isolation & purification
13.
Indian J Pharmacol ; 53(6): 499-510, 2021.
Article in English | MEDLINE | ID: covidwho-1603884

ABSTRACT

BACKGROUND: Till now, no meta-analysis is available to address the clinical profile, risk factors, different interventions, and outcomes among COVID-19-associated rhino-orbito-cerebral mucormycosis (C-ROCM) cases. MATERIALS AND METHODS: Eight literature databases were screened using appropriate keywords from November 1, 2019, to June 30, 2021. The objectives were to analyze the clinical and microbiological profile, risk factor/comorbidity, intervention, and outcome. "R-metafor package" was used for analysis. RESULTS: A total of 23 studies were included. The mean age of presentation of C-ROCM was 54.6 years. The most common presentation was ptosis (72.7%), lid edema (60.6%), proptosis (60.6%), ophthalmoplegia (57.3%), loss of vision (53.7%), facial edema (34.7%), and nasal-blockage (11.8%). Evidence of intracranial spread was seen in 42.8% of cases. Rhizopus was the most common fungus (57.1%) isolated in fungal culture. Among C-ROCM patients, diabetes was the commonest comorbid condition, and the use of corticosteroids related to COVID-19 treatment was the most common risk factor (85.75%). Compared to controlled diabetics, C-ROCM was significantly higher among uncontrolled diabetics (odds ratio [OR] 0.15, 95% confidence interval [C.I.] 0.041-0.544, P = 0.0010). However, no significant association was seen between C-ROCM and COVID-19 severity (OR 0.930, 95% C.I. 0.212-4.087, P = 0.923). For treatment, amphotericin-B was the most common antifungal drug used which was followed by surgical options. However, mortality was high (prevalence 0.344, 95% C.I. 0.205-0.403) despite treatment. CONCLUSION: Although local rhino-orbito symptoms were the first to appear, rapid intracranial extension was seen in a significant number of C-ROCM cases. Uncontrolled diabetes and excessive use of corticosteroid were the most common risk factors present among the C-ROCM cases. High index clinical suspicion is imperative (specifically among COVID-19 patients with diabetes), and routine screening may be helpful.


Subject(s)
Brain Diseases/complications , COVID-19/complications , Mucormycosis/complications , Nose Diseases/complications , Orbital Diseases/complications , Amphotericin B/therapeutic use , Antifungal Agents/therapeutic use , Brain Diseases/drug therapy , COVID-19/virology , Humans , Mucormycosis/drug therapy , Nose Diseases/drug therapy , Orbital Diseases/drug therapy , Regression Analysis , Risk Factors , SARS-CoV-2/isolation & purification
14.
Indian J Pharmacol ; 53(6): 493-498, 2021.
Article in English | MEDLINE | ID: covidwho-1603657

ABSTRACT

Coronavirus disease-2019 (COVID-19) is a novel viral infectious disease that the World Health Organization (WHO) has announced to be a pandemic. This meta-analysis was aimed at providing evidence for the use of ivermectin to prevent COVID-19 among hospital workers in low-resource countries. Medical databases including African Journals online, Google Scholar, PubMed, Cochrane library, EMBASE, COVID-19 research database (WHO), Clinicaltrials.gov, and SCOPUS were searched for studies on Ivermectin as a chemoprophylactic drug against COVID-19 among hospital personnel in settings with limited resources. Preprint servers such as bioRxiv and medRxiv as well as the gray literature were also searched. Studies adjudged to be eligible were identified using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses algorithm. Statistical analyses were done using Stata version 14.3. Seven studies were selected for the meta-analysis. The total sample size was 2652. There were two randomized controlled trials and five nonrandomized studies. Some studies dosed Ivermectin daily while some dosed it weekly. However, one of the studies dosed it monthly. The studies reported variable clinical benefits. I2 statistic was 92%, and random effect model was used. The pooled odd ratio was 0.11 (95% confidence interval 0.09-0.13). This implies that 89% of the participants benefited from taking Ivermectin as a form of preexposure chemoprophylaxis. Ivermectin has a significant clinical benefit as a preventive drug against COVID-19 for hospital personnel in settings with limited resources.


Subject(s)
COVID-19/prevention & control , Chemoprevention/methods , Health Personnel , COVID-19/virology , Developing Countries , Humans , Ivermectin/administration & dosage , SARS-CoV-2/isolation & purification
16.
Sci Rep ; 11(1): 24470, 2021 12 28.
Article in English | MEDLINE | ID: covidwho-1594859

ABSTRACT

A novel severe acute respiratory syndrome coronavirus 2 emerged in December 2019, and it took only a few months for WHO to declare COVID-19 as a pandemic in March 2020. It is very challenging to discover complex spatial-temporal transmission mechanisms. However, it is crucial to capture essential features of regional-temporal patterns of COVID-19 to implement prompt and effective prevention or mitigation interventions. In this work, we develop a novel framework of compatible window-wise dynamic mode decomposition (CwDMD) for nonlinear infectious disease dynamics. The compatible window is a selected representative subdomain of time series data, in which compatibility between spatial and temporal resolutions is established so that DMD can provide meaningful data analysis. A total of four compatible windows have been selected from COVID-19 time-series data from January 20, 2020, to May 10, 2021, in South Korea. The spatiotemporal patterns of these four windows are then analyzed. Several hot and cold spots were identified, their spatial-temporal relationships, and some hidden regional patterns were discovered. Our analysis reveals that the first wave was contained in the Daegu and Gyeongbuk areas, but it spread rapidly to the whole of South Korea after the second wave. Later on, the spatial distribution is seen to become more homogeneous after the third wave. Our analysis also identifies that some patterns are not related to regional relevance. These findings have then been analyzed and associated with the inter-regional and local characteristics of South Korea. Thus, the present study is expected to provide public health officials helpful insights for future regional-temporal specific mitigation plans.


Subject(s)
COVID-19/epidemiology , Algorithms , COVID-19/mortality , COVID-19/virology , Humans , Republic of Korea/epidemiology , SARS-CoV-2/isolation & purification , Spatio-Temporal Analysis , Time Factors
17.
Small Methods ; 5(5): e2001108, 2021 05.
Article in English | MEDLINE | ID: covidwho-1599126

ABSTRACT

During the global outbreak of COVID-19 pandemic, "cytokine storm" conditions are regarded as the fatal step resulting in most mortality. Hemoperfusion is widely used to remove cytokines from the blood of severely ill patients to prevent uncontrolled inflammation induced by a cytokine storm. This article discoveres, for the first time, that 2D Ti3 C2 Tx MXene sheet demonstrates an ultrahigh removal capability for typical cytokine interleukin-6. In particular, MXene shows a 13.4 times higher removal efficiency over traditional activated carbon absorbents. Molecular-level investigations reveal that MXene exhibits a strong chemisorption mechanism for immobilizing cytokine interleukin-6 molecules, which is different from activated carbon absorbents. MXene sheet also demonstrates excellent blood compatibility without any deleterious side influence on the composition of human blood. This work can open a new avenue to use MXene sheets as an ultraefficient hemoperfusion absorbent to eliminate the cytokine storm syndrome in treatment of severe COVID-19 patients.


Subject(s)
COVID-19/immunology , Cytokine Release Syndrome/drug therapy , Hemoperfusion/methods , Nanostructures/administration & dosage , SARS-CoV-2/immunology , Titanium/administration & dosage , Adsorption , COVID-19/transmission , COVID-19/virology , Cytokine Release Syndrome/blood , Cytokine Release Syndrome/virology , Humans , Interleukin-6/immunology , Nanostructures/chemistry , SARS-CoV-2/isolation & purification , Titanium/chemistry
19.
Sci Rep ; 11(1): 24467, 2021 12 28.
Article in English | MEDLINE | ID: covidwho-1596771

ABSTRACT

Mobility restrictions are successfully used to contain the diffusion of epidemics. In this work we explore their effect on the epidemic growth by investigating an extension of the Susceptible-Infected-Removed (SIR) model in which individual mobility is taken into account. In the model individual agents move on a chessboard with a Lévy walk and, within each square, epidemic spreading follows the standard SIR model. These simple rules allow to reproduce the sub-exponential growth of the epidemic evolution observed during the Covid-19 epidemic waves in several countries and which cannot be captured by the standard SIR model. We show that we can tune the slowing-down of the epidemic spreading by changing the dynamics of the agents from Lévy to Brownian and we investigate how the interplay among different containment strategies mitigate the epidemic spreading. Finally we demonstrate that we can reproduce the epidemic evolution of the first and second COVID-19 waves in Italy using only 3 parameters, i.e , the infection rate, the removing rate, and the mobility in the country. We provide an estimate of the peak reduction due to imposed mobility restrictions, i. e., the so-called flattening the curve effect. Although based on few ingredients, the model captures the kinetic of the epidemic waves, returning mobility values that are consistent with a lock-down intervention during the first wave and milder limitations, associated to a weaker peak reduction, during the second wave.


Subject(s)
COVID-19/epidemiology , Models, Theoretical , Movement , COVID-19/virology , Epidemics , Humans , Italy/epidemiology , SARS-CoV-2/isolation & purification
20.
Nat Microbiol ; 7(1): 97-107, 2022 01.
Article in English | MEDLINE | ID: covidwho-1596437

ABSTRACT

Global and national surveillance of SARS-CoV-2 epidemiology is mostly based on targeted schemes focused on testing individuals with symptoms. These tested groups are often unrepresentative of the wider population and exhibit test positivity rates that are biased upwards compared with the true population prevalence. Such data are routinely used to infer infection prevalence and the effective reproduction number, Rt, which affects public health policy. Here, we describe a causal framework that provides debiased fine-scale spatiotemporal estimates by combining targeted test counts with data from a randomized surveillance study in the United Kingdom called REACT. Our probabilistic model includes a bias parameter that captures the increased probability of an infected individual being tested, relative to a non-infected individual, and transforms observed test counts to debiased estimates of the true underlying local prevalence and Rt. We validated our approach on held-out REACT data over a 7-month period. Furthermore, our local estimates of Rt are indicative of 1-week- and 2-week-ahead changes in SARS-CoV-2-positive case numbers. We also observed increases in estimated local prevalence and Rt that reflect the spread of the Alpha and Delta variants. Our results illustrate how randomized surveys can augment targeted testing to improve statistical accuracy in monitoring the spread of emerging and ongoing infectious disease.


Subject(s)
COVID-19/epidemiology , Models, Statistical , SARS-CoV-2/isolation & purification , Basic Reproduction Number , Bias , COVID-19/diagnosis , COVID-19/transmission , COVID-19 Testing/statistics & numerical data , Forecasting , Humans , Prevalence , Reproducibility of Results , SARS-CoV-2/genetics , Spatio-Temporal Analysis , United Kingdom/epidemiology
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