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1.
Small ; : e2205010, 2022 Nov 03.
Article in English | MEDLINE | ID: covidwho-2094245

ABSTRACT

Commercial masks have significant drawbacks, including low water vapor transmission efficiency and limited ability to inhibit harmful microorganisms, whereas in this contribution, a series of Janus microsphere membranes are developed with hierarchical structures by quenching and crystallizing 12-hydroxystearic acid and halicin layer-by-layer on a polypropylene non-woven fabric, laminating them with hydrophilic cotton fibers in a one-pot process, and further demonstrate the potential of this composite system as masks. Through further optimization, excellent superhydrophobic/superhydrophilic properties (contact angle 157.1°/0°), superior filtering effects (93.54% for PM2.5 and 98.35% for PM10 ), with a low-filtration resistance (57 Pa) and a quality factor of up to 0.072 Pa-1 are achieved, all better than that of commercial N95 masks. In addition, the membrane allows for the directional transport of water vapor from the inside out, increasing the water vapor transmission rate by more than 20% compared with the monolayer hydrophobic microsphere membrane. It also has a bactericidal capacity of over 99.9999% against Escherichia coli and is tested for robustness and stability in various extreme environments. This work may shed light on designing novel filter media with versatile functions, meanwhile, the materials can also be used in protective equipment against the new coronavirus.

2.
Diagnostics (Basel) ; 12(5)2022 May 13.
Article in English | MEDLINE | ID: covidwho-1855557

ABSTRACT

Measuring immunity to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of coronavirus disease 19 (COVID-19), can rely on antibodies, reactive T cells and other factors, with T-cell-mediated responses appearing to have greater sensitivity and longevity. Because each T cell carries an essentially unique nucleic acid sequence for its T-cell receptor (TCR), we can interrogate sequence data derived from DNA or RNA to assess aspects of the immune response. This review deals with the utility of bulk, rather than single-cell, sequencing of TCR repertoires, considering the importance of study design, in terms of cohort selection, laboratory methods and analysis. The advances in understanding SARS-CoV-2 immunity that have resulted from bulk TCR repertoire sequencing are also be discussed. The complexity of sequencing data obtained by bulk repertoire sequencing makes analysis challenging, but simple descriptive analyses, clonal analysis, searches for specific sequences associated with immune responses to SARS-CoV-2, motif-based analyses, and machine learning approaches have all been applied. TCR repertoire sequencing has demonstrated early expansion followed by contraction of SARS-CoV-2-specific clonotypes, during active infection. Maintenance of TCR repertoire diversity, including the maintenance of diversity of anti-SARS-CoV-2 response, predicts a favourable outcome. TCR repertoire narrowing in severe COVID-19 is most likely a consequence of COVID-19-associated lymphopenia. It has been possible to follow clonotypic sequences longitudinally, which has been particularly valuable for clonotypes known to be associated with SARS-CoV-2 peptide/MHC tetramer binding or with SARS-CoV-2 peptide-induced cytokine responses. Closely related clonotypes to these previously identified sequences have been shown to respond with similar kinetics during infection. A possible superantigen-like effect of the SARS-CoV-2 spike protein has been identified, by means of observing V-segment skewing in patients with severe COVID-19, together with structural modelling. Such a superantigen-like activity, which is apparently absent from other coronaviruses, may be the basis of multisystem inflammatory syndrome and cytokine storms in COVID-19. Bulk TCR repertoire sequencing has proven to be a useful and cost-effective approach to understanding interactions between SARS-CoV-2 and the human host, with the potential to inform the design of therapeutics and vaccines, as well as to provide invaluable pathogenetic and epidemiological insights.

3.
Front Pharmacol ; 11: 540187, 2020.
Article in English | MEDLINE | ID: covidwho-782038

ABSTRACT

OBJECTIVE: The quality and rationality of many recently registered clinical studies related to coronavirus disease 2019 (COVID-19) needs to be assessed. Hence, this study aims to evaluate the current status of COVID-19 related registered clinical trial. METHODS: We did an electronic search of COVID-19 related clinical studies registered between December 1, 2019 and February 21, 2020 (updated to May 28, 2020) from the ClinicalTrials.gov, and collected registration information, study details, recruitment status, characteristics of the subjects, and relevant information about the trial implementation process. RESULTS: A total of 1,706 studies were included 10.0% of which (n=171) were from France, 943 (55.3%) used an interventional design, and 600 (35.2%) used an observational design. Most of studies (73.6%) aimed to recruit fewer than 500 people. Interferon was the main prevention program, and antiviral drugs were the main treatment program. Hydroxychloroquine and chloroquine (230/943, 24.4%) were widely studied. Some registered clinical trials are incomplete in content, and 37.4% of the 1,706 studies may have had insufficient sample size. CONCLUSION: The quality of COVID-19 related studies needs to be improved by strengthening the registration process and improving the quality of clinical study protocols so that these clinical studies can provide high-quality clinical evidence related to COVID-19.

4.
Chin. J. Evid.-Based Med. ; 6(20):723-736, 2020.
Article in Chinese | ELSEVIER | ID: covidwho-739130

ABSTRACT

Objective To develop the questionnaire and test its reliability for investigating route, prevention, and control of SARS-CoV-2 infection in medical staffs. Methods This questionnaire was development based on the COVID-19 relevant guidelines, official documents issued by the National Health Committee of the People's Republic of China, and published studies. The development group performed repeated discussions and drafted the first questionnaire, then performed expert consultation and revised the draft according to their suggestions. Eventually, some frontline medical staffs were invited to carry out pre-test investigation of the questionnaire and test its reliability. Results The first draft included 48 items;18 experts were invited in the first round questionnaire and 10 experts in the second round questionnaire. The positive coefficient of experts in these two rounds was both greater than 75%, and the authority coefficient of experts' opinions was greater than 0.70. The variation coefficient of these items was between 0.00 and 0.35, the coordination coefficient of experts was 0.193 (P<0.05). The experts of above two rounds put forward 14 suggestions for text modification or adjustment options of some items;after the development group held repeatedly discussions, a total of 8 items were performed secondary consultation and finally reached consensus. The final questionnaire included two domains of questionnaire before and after confirmed diagnosis. The domain "before confirmed diagnosis" covered 4 sections and 29 items involving infectious cause, plan and knowledge of prevention and control, and psychological symptoms. The domain "after confirmed diagnosis" covered 5 sections and 21 items, included symptoms, treatment, and psychological status after diagnosis;impact on the surrounding environment and people, and awareness of protection after infection. The pre-test results showed that the total items were considerably numerous, some items were difficult to understand, some laboratory results and treatment conditions were ambiguous, etc. After modification and re-testing, the test-re-test reliability of each domain was between 0.74 and 0.93, and the overall re-test reliability of the questionnaire content was 0.82. Conclusions This research has developed a questionnaire for investigating infection process, prevention and control of SARS-CoV-2 infection in medical staff, and the items considered two domains prior to and after confirmed diagnosis. The reliability and practicability of the questionnaire are acceptable.

5.
Front Med (Lausanne) ; 7: 242, 2020.
Article in English | MEDLINE | ID: covidwho-547968

ABSTRACT

Recently WHO has characterized COVID-19 as a pandemic. Diagnosing the disease accurately and decreasing misdiagnoses and missed diagnoses is very important for management. Therefore, we have analyzed the seven versions of China's national guidelines to examine how the diagnostic criteria roadmap has developed and evolved, in order to share our experience worldwide. In this article, we present the developments from the first to seventh versions, involving changes of case classification, changes to "suspected case," changes in "confirmed case," changes in clinical classifications, changes in "severe case," and unchanged criteria. We have also discussed the reasons and implications for these changes and are looking forward to providing suggestions for worldwide understanding and management of this pandemic. A nucleic acid test is currently accepted as the gold standard method to confirm diagnosis. In addition, imaging examination and epidemiological history should also be considered as auxiliary diagnosis methods.

6.
Mil Med Res ; 7(1): 24, 2020 05 11.
Article in English | MEDLINE | ID: covidwho-232557

ABSTRACT

BACKGROUND: Many healthcare workers were infected by coronavirus disease 2019 (COVID-19) early in the epidemic posing a big challenge for epidemic control. Hence, this study aims to explore perceived infection routes, influencing factors, psychosocial changes, and management procedures for COVID-19 infected healthcare workers. METHODS: This is a cross-sectional, single hospital-based study. We recruited all 105 confirmed COVID-19 healthcare workers in the Zhongnan Hospital of Wuhan University from February 15 to 29, 2020. All participants completed a validated questionnaire. Electronic consent was obtained from all participants. Perceived causes of infection, infection prevention, control knowledge and behaviour, psychological changes, symptoms and treatment were measured. RESULTS: Finally, 103 professional staff with COVID-19 finished the questionnaire and was included (response rate: 98.1%). Of them, 87 cases (84.5%) thought they were infected in working environment in hospital, one (1.0%) thought their infection was due to the laboratory environment, and 5 (4.9%) thought they were infected in daily life or community environment. Swab of throat collection and physical examination were the procedures perceived as most likely causing their infection by nurses and doctors respectively. Forty-three (41.8%) thought their infection was related to protective equipment, utilization of common equipment (masks and gloves). The top three first symptoms displayed before diagnosis were fever (41.8%), lethargy (33.0%) and muscle aches (30.1%). After diagnosis, 88.3% staff experienced psychological stress or emotional changes during their isolation period, only 11.7% had almost no emotional changes. Arbidol (Umifenovir; an anti-influza drug; 69.2%) was the drug most commonly used to target infection in mild and moderate symptoms. CONCLUSION: The main perceived mode of transmission was not maintaining protection when working at a close distance and having intimate contact with infected cases. Positive psychological intervention is necessary.


Subject(s)
Coronavirus Infections/prevention & control , Coronavirus Infections/psychology , Coronavirus Infections/transmission , Health Personnel/psychology , Infection Control/methods , Pandemics/prevention & control , Pneumonia, Viral/prevention & control , Pneumonia, Viral/psychology , Pneumonia, Viral/transmission , Adult , Betacoronavirus , COVID-19 , China , Cross-Sectional Studies , Female , Humans , Male , Middle Aged , Occupational Exposure , Personal Protective Equipment , SARS-CoV-2 , Stress, Psychological , Surveys and Questionnaires , Tertiary Care Centers , Young Adult
7.
Mil Med Res ; 7(1): 4, 2020 02 06.
Article in English | MEDLINE | ID: covidwho-405

ABSTRACT

In December 2019, a new type viral pneumonia cases occurred in Wuhan, Hubei Province; and then named "2019 novel coronavirus (2019-nCoV)" by the World Health Organization (WHO) on 12 January 2020. For it is a never been experienced respiratory disease before and with infection ability widely and quickly, it attracted the world's attention but without treatment and control manual. For the request from frontline clinicians and public health professionals of 2019-nCoV infected pneumonia management, an evidence-based guideline urgently needs to be developed. Therefore, we drafted this guideline according to the rapid advice guidelines methodology and general rules of WHO guideline development; we also added the first-hand management data of Zhongnan Hospital of Wuhan University. This guideline includes the guideline methodology, epidemiological characteristics, disease screening and population prevention, diagnosis, treatment and control (including traditional Chinese Medicine), nosocomial infection prevention and control, and disease nursing of the 2019-nCoV. Moreover, we also provide a whole process of a successful treatment case of the severe 2019-nCoV infected pneumonia and experience and lessons of hospital rescue for 2019-nCoV infections. This rapid advice guideline is suitable for the first frontline doctors and nurses, managers of hospitals and healthcare sections, community residents, public health persons, relevant researchers, and all person who are interested in the 2019-nCoV.


Subject(s)
Betacoronavirus , Coronavirus Infections , Cross Infection , Infection Control , Mass Screening , Personal Protective Equipment , Pneumonia, Viral , Anti-Bacterial Agents/therapeutic use , Antiviral Agents/therapeutic use , Betacoronavirus/isolation & purification , Betacoronavirus/pathogenicity , COVID-19 , COVID-19 Testing , Clinical Laboratory Techniques , Coronavirus Infections/diagnosis , Coronavirus Infections/drug therapy , Coronavirus Infections/epidemiology , Coronavirus Infections/therapy , Coronavirus Infections/transmission , Cross Infection/prevention & control , Diagnosis, Differential , Drugs, Chinese Herbal , Evidence-Based Medicine , Fluid Therapy , Humans , Infection Control/standards , Lung/diagnostic imaging , Molecular Epidemiology , Nursing Care , Pneumonia, Viral/diagnosis , Pneumonia, Viral/epidemiology , Pneumonia, Viral/etiology , Pneumonia, Viral/therapy , Pneumonia, Viral/transmission , SARS-CoV-2 , COVID-19 Drug Treatment
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