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1.
Reactive and Functional Polymers ; 175:105268, 2022.
Article in English | ScienceDirect | ID: covidwho-1796182

ABSTRACT

The global spread of COVID-19 continues, industrial raw material production is being tested, and the fracturing cost of oil and gas fields continues to rise, posing new challenges to polymer fracturing fluids. A new hydrophobic association polymer PDMA1 with a double tailed monomer structure was synthesized inside this study. Fourier infrared spectroscopy, Electron microscope scanning, Fluorescence spectroscopy, and polymer viscoelasticity were used to investigate the polymer's basic properties. Finally, using molecular dynamics simulation tools, the network structure of PDMA1 was discovered to be more temperature resistant than that of HPAM. PDMA1 has larger hydrodynamic dimensions than HPAM at the same temperature, its radius of gyration is more than HPAM, and its viscosity is greater than HPAM under the same conditions. This provides an additional avenue of investigation for temperature-resistant hydrophobically associating polymers.

2.
Applied Intelligence ; : 1-16, 2022.
Article in English | EuropePMC | ID: covidwho-1782300

ABSTRACT

COVID-19 is an infectious pneumonia caused by 2019-nCoV. The number of newly confirmed cases and confirmed deaths continues to remain at a high level. RT–PCR is the gold standard for the COVID-19 diagnosis, but the computed tomography (CT) imaging technique is an important auxiliary diagnostic tool. In this paper, a deep learning network mutex attention network (MA-Net) is proposed for COVID-19 auxiliary diagnosis on CT images. Using positive and negative samples as mutex inputs, the proposed network combines mutex attention block (MAB) and fusion attention block (FAB) for the diagnosis of COVID-19. MAB uses the distance between mutex inputs as a weight to make features more distinguishable for preferable diagnostic results. FAB acts to fuse features to obtain more representative features. Particularly, an adaptive weight multiloss function is proposed for better effect. The accuracy, specificity and sensitivity were reported to be as high as 98.17%, 97.25% and 98.79% on the COVID-19 dataset-A provided by the Affiliated Medical College of Qingdao University, respectively. State-of-the-art results have also been achieved on three other public COVID-19 datasets. The results show that compared with other methods, the proposed network can provide effective auxiliary information for the diagnosis of COVID-19 on CT images.

3.
EuropePMC; 2021.
Preprint in English | EuropePMC | ID: ppcovidwho-324456

ABSTRACT

Background: The COVID-19 epidemic affected the career choice of healthcare professionals and students. To explore career choice regret of healthcare professionals and students during COVID-19 outbreak and its affected factors. Methods: Convenience sample of nurses, doctors, and medical students were recruited from hospitals and universities nationwide. The data collected including demographic information, professional value before and after the COVID-19 outbreak, the Connor-Davidson Resilience Scale, and career choice regret level by an online questionnaire. Multinominal logistic regression was employed to explore the factors associated with career choice regret. Results: In total, 9322 participants of convenience sampling were enrolled in, including 5786 nurses, 1664 doctors, and 1872 medical students. 6.7% participants had career choice regret. Multinominal logistic regression analysis showed, compared to participants with no regret, that as levels of resilience increased, the odds of experiencing career choice regret decreased (OR=0.951,P<0.001), while participants with lower professional value evaluation after the COVID-19 outbreak had higher probability to experience career choice regret(OR=1.552,P<0.001). Medical students were more likely to regret than nurses (OR=1.654,P=0.002), participants whose career/major choice was according to their personal ideal had higher risk of experience career choice regret (OR=1.592,P<0.001), while participants who were very afraid of the coronavirus had higher risk to experience career choice regret then participants with no fear at all(OR=1.997,P=0.004).As for the medical students, results indicated that medical students major in nursing and undergraduates had higher risk to experience career choice regret compared to medical students major in clinical medicine and postgraduate (Master or PhD), with an odds ratios of 2.645 and 6.851 respectively. Conclusions: A minority of healthcare professionals and medical students regretted their career choices during the COVID-19 outbreak. Enhance personal psychological resilience and professional value would helpful to reduce career choice regret among healthcare professionals and students during pandemic.

4.
EuropePMC; 2020.
Preprint in English | EuropePMC | ID: ppcovidwho-323543

ABSTRACT

Objective: To examine the impact of respiratory infectious disease pandemics in the new millennium on mental health, behavioral responses, and parenting practices in children, and provide further intervention directions to mitigate negative effects of the 2019 novel coronavirus disease (COVID-19). Methods We conducted a systemic literature review of researches from January 2003 to May 2020 with three mainstream electronic databases including PubMed, Web of Science, and China National Knowledge Infrastructure. Quality of included studies were assessed using Agency for Healthcare Research and Quality (AHRQ), Newcastle-Ottawa Scale (NOS), and Critical Appraisal Skills Programme (CASP) according to different study design. Further directions were identified for developing appropriate interventions. Results Twenty-four studies conducted in the context of severe acute respiratory syndrome (SARS) (n = 10), influenza A (H1N1) (n = 3), and COVID-19 (n = 11) pandemics met the inclusion criteria. Children showed emotional conditions such as anxiety, fear, and depression, while psychological responses varied across age and gender groups. Children with mental illness history experienced an exacerbation of psychological symptoms. The pandemics changed hygiene habits and learning styles, and led to the increased participation in unfavorable lifestyles. For families with pediatric patients, the pandemic decreased parents’ participation in providing family-centered care and threatened to supportive family relationship and effective parents-child communication. Conclusion The emerging virus outbreaks and subsequent disease-control measures have impacts on mental health status, behavioral responses, and parenting practices in children. In response to COVID-19, greater efforts taking into account children’s developmental stage should be made to implement evidence-based psychological interventions, enhance effective communication, and encourage collaboration.

5.
EuropePMC; 2020.
Preprint in English | EuropePMC | ID: ppcovidwho-315664

ABSTRACT

Background: No study has revealed spatial transmission characteristics of COVID-19 in Wuhan, China. We aimed to analyze the spatiotemporal spread of COVID-19 in Wuhan and its influence factors. Methods: : Information of 32,682 COVID-19 cases reported through March 18 were extracted from the national infectious disease surveillance system. Geographic information system methods were applied to analysis transmission of COVID-19 and its influence factors in different periods. Results: : We found decrease in effective reproduction number ( Rt ) and COVID-19 related indicators through taking a series of effective public health measures including restricting traffic, centralized quarantine and strict stay-at home policy. The distribution of COVID-19 cases number in Wuhan showed an obvious global aggregation and a local aggregation in central urban areas, but such aggregations was decreased in the later period of the epidemic. In addition, the analysis at streets-level suggested population density and the number of hospitals were influence factors of spatial difference. Conclusions: : The epidemic situation showed obvious global and local spatial aggregations. High population density and directional flow of the Population to hospitals may account for the aggregations. Strong quarantine measures and restrictions on movement of residents in Wuhan make the epidemic under control in a short time.

6.
EuropePMC; 2020.
Preprint in English | EuropePMC | ID: ppcovidwho-308343

ABSTRACT

Background: Prior studies reported that 5~32% COVID-19 patients were critically ill, a situation that poses great challenge for the management of the patients and ICU resources. We aim to identify independent risk factors to serve as prediction markers for critical illness of SARS-CoV-2 infection. Methods Fifty-two critical and 200 non-critical SARS-CoV-2 nucleic acid positive patients hospitalized in 15 hospitals outside Wuhan from January 19 to March 6, 2020 were enrolled in this study. Multivariable logistic regression and LASSO logistic regression were performed to identify independent risk factors for critical illness. Results Age older than 60 years, dyspnea, respiratory rate > 24 breaths per min, leukocytosis >9.5 X10 9 /L, neutrophilia >6.3 X10 9 /L, lymphopenia <1.1 X10 9 /L, neutrophil-to-lymphocyte ratio >3.53, fibrinogen >4g/L, d-dimer >0.55 µg/mL, blood urea nitrogen >7.1 mM, elevated aspartate transaminase, elevated alanine aminotransferase, total bilirubin >21 µM, and Sequential Organ Failure Assessment (SOFA) score ≥2 were identified as risk factors for critical illness. LASSO logistic regression identified the best combination of risk factors as SOFA score, age, dyspnea, and leukocytosis. The Area Under the Receiver-Operator Curve values for the risk factors in predicting critical illness were 0.921 for SOFA score, 0.776 for age, 0.764 for dyspnea, 0.658 for leukocytosis, and 0.960 for the combination of the four risk factors. Conclusions Our findings advocate the use of risk factors SOFA score ≥2, age >60, dyspnea and leukocytosis >9.5 X10 9 /L on admission, alone or in combination, to determine the optimal management of the patients and health care resources.

7.
Eur Radiol ; 32(4): 2235-2245, 2022 Apr.
Article in English | MEDLINE | ID: covidwho-1606144

ABSTRACT

BACKGROUND: Main challenges for COVID-19 include the lack of a rapid diagnostic test, a suitable tool to monitor and predict a patient's clinical course and an efficient way for data sharing among multicenters. We thus developed a novel artificial intelligence system based on deep learning (DL) and federated learning (FL) for the diagnosis, monitoring, and prediction of a patient's clinical course. METHODS: CT imaging derived from 6 different multicenter cohorts were used for stepwise diagnostic algorithm to diagnose COVID-19, with or without clinical data. Patients with more than 3 consecutive CT images were trained for the monitoring algorithm. FL has been applied for decentralized refinement of independently built DL models. RESULTS: A total of 1,552,988 CT slices from 4804 patients were used. The model can diagnose COVID-19 based on CT alone with the AUC being 0.98 (95% CI 0.97-0.99), and outperforms the radiologist's assessment. We have also successfully tested the incorporation of the DL diagnostic model with the FL framework. Its auto-segmentation analyses co-related well with those by radiologists and achieved a high Dice's coefficient of 0.77. It can produce a predictive curve of a patient's clinical course if serial CT assessments are available. INTERPRETATION: The system has high consistency in diagnosing COVID-19 based on CT, with or without clinical data. Alternatively, it can be implemented on a FL platform, which would potentially encourage the data sharing in the future. It also can produce an objective predictive curve of a patient's clinical course for visualization. KEY POINTS: • CoviDet could diagnose COVID-19 based on chest CT with high consistency; this outperformed the radiologist's assessment. Its auto-segmentation analyses co-related well with those by radiologists and could potentially monitor and predict a patient's clinical course if serial CT assessments are available. It can be integrated into the federated learning framework. • CoviDet can be used as an adjunct to aid clinicians with the CT diagnosis of COVID-19 and can potentially be used for disease monitoring; federated learning can potentially open opportunities for global collaboration.


Subject(s)
Artificial Intelligence , COVID-19 , Algorithms , Humans , Radiologists , Tomography, X-Ray Computed/methods
8.
EuropePMC; 2021.
Preprint in English | EuropePMC | ID: ppcovidwho-293469

ABSTRACT

Background: The potential roles of affective responses to environmental stressors in individuals' physical and mental health are complex and multi-faceted. This study, then, explores Chinese citizens' emotional responses to COVID-19-related stressors and influence factors which may boost or buffer such effects. Methods: From late March to early June (2020), a cross-sectional study was conducted using an anonymous online questionnaire included demographic characteristics, COVID-19-related stressors related to individuals' daily functioning, and the self-assessed impact of protective and adverse internal factors on emotions. Results: 1,662 questionnaires were received from residents in 32 Chinese provinces classified by prevalence level according to COVID-19 infections. Among the 17 positive and negative emotional responses, agglomerative hierarchical clustering revealed four subclassifications: (1) stress relations;(2) missing someone relations;(3) individual relations;and (4) social relations. Additionally, heightened regional prevalence levels positively corresponded to intensity of stress relations. Lowest intensity of social relations was found in the areas surrounding Wuhan and coastal areas. Specially, economic- and work-related stressors as well as negative self-perceptions (e.g., suppression, emotionally unstable, self-denial) implicated in negative emotions. While positive emotions were tied to demographic characteristics (e.g., high education, young age and male) and protective traits (e.g., creativity, sympathy, social responsibility), and inversely linked to relationships- and pandemic-related stressors, etc. Conclusion: Associations were clearly noted among Chinese residents' emotions to specific stressors during pandemic. Providing appropriate psychological resources/supports during future or extended public health crises may help offset the cognitive burden of individuals striving to regain an adequate level of normalcy and emotional well-being.

9.
IEEE Access ; 8: 185786-185795, 2020.
Article in English | MEDLINE | ID: covidwho-1528291

ABSTRACT

Since the first patient reported in December 2019, 2019 novel coronavirus disease (COVID-19) has become global pandemic with more than 10 million total confirmed cases and 500 thousand related deaths. Using deep learning methods to quickly identify COVID-19 and accurately segment the infected area can help control the outbreak and assist in treatment. Computed tomography (CT) as a fast and easy clinical method, it is suitable for assisting in diagnosis and treatment of COVID-19. According to clinical manifestations, COVID-19 lung infection areas can be divided into three categories: ground-glass opacities, interstitial infiltrates and consolidation. We proposed a multi-scale discriminative network (MSD-Net) for multi-class segmentation of COVID-19 lung infection on CT. In the MSD-Net, we proposed pyramid convolution block (PCB), channel attention block (CAB) and residual refinement block (RRB). The PCB can increase the receptive field by using different numbers and different sizes of kernels, which strengthened the ability to segment the infected areas of different sizes. The CAB was used to fusion the input of the two stages and focus features on the area to be segmented. The role of RRB was to refine the feature maps. Experimental results showed that the dice similarity coefficient (DSC) of the three infection categories were 0.7422,0.7384,0.8769 respectively. For sensitivity and specificity, the results of three infection categories were (0.8593, 0.9742), (0.8268,0.9869) and (0.8645,0.9889) respectively. The experimental results demonstrated that the network proposed in this paper can effectively segment the COVID-19 infection on CT images. It can be adopted for assisting in diagnosis and treatment of COVID-19.

10.
Healthcare (Basel) ; 9(11)2021 Nov 20.
Article in English | MEDLINE | ID: covidwho-1523946

ABSTRACT

Previous research has revealed that environmental, social, and cultural factors affect people's risk perception of COVID-19, especially the influence of media and trust, while the dynamics of how they affect it is still not clear. Through the analysis of online survey data, this article shows that there are two opposed paths of action. Trust in the government will enhance people's confidence in controlling COVID-19. It then moderates and decreases the effects of people's level and frequency of concernon the risk perception (both cognition and worries) of COVID-19, on the contrary, obtaining information from unofficial channels also moderates and increases the effects of the people's level and frequency of concern on the second dimension (worries) of risk perception of COVID-19 rather than the first dimension (cognition). These conclusions have important policy implications for the control of the COVID-19 epidemic all over the world.

11.
JAMA Netw Open ; 4(11): e2135379, 2021 11 01.
Article in English | MEDLINE | ID: covidwho-1520147

ABSTRACT

Importance: There is a need for studies to evaluate the risk factors for COVID-19 and mortality among the entire Medicare long-term dialysis population using Medicare claims data. Objective: To identify risk factors associated with COVID-19 and mortality in Medicare patients undergoing long-term dialysis. Design, Setting, and Participants: This retrospective, claims-based cohort study compared mortality trends of patients receiving long-term dialysis in 2020 with previous years (2013-2019) and fit Cox regression models to identify risk factors for contracting COVID-19 and postdiagnosis mortality. The cohort included the national population of Medicare patients receiving long-term dialysis in 2020, derived from clinical and administrative databases. COVID-19 was identified through Medicare claims sources. Data were analyzed on May 17, 2021. Main Outcomes and Measures: The 2 main outcomes were COVID-19 and all-cause mortality. Associations of claims-based risk factors with COVID-19 and mortality were investigated prediagnosis and postdiagnosis. Results: Among a total of 498 169 Medicare patients undergoing dialysis (median [IQR] age, 66 [56-74] years; 215 935 [43.1%] women and 283 227 [56.9%] men), 60 090 (12.1%) had COVID-19, among whom 15 612 patients (26.0%) died. COVID-19 rates were significantly higher among Black (21 787 of 165 830 patients [13.1%]) and Hispanic (13 530 of 86 871 patients [15.6%]) patients compared with non-Black patients (38 303 of 332 339 [11.5%]), as well as patients with short (ie, 1-89 days; 7738 of 55 184 patients [14.0%]) and extended (ie, ≥90 days; 10 737 of 30 196 patients [35.6%]) nursing home stays in the prior year. Adjusting for all other risk factors, residing in a nursing home 1 to 89 days in the prior year was associated with a higher hazard for COVID-19 (hazard ratio [HR] vs 0 days, 1.60; 95% CI 1.56-1.65) and for postdiagnosis mortality (HR, 1.31; 95% CI, 1.25-1.37), as was residing in a nursing home for an extended stay (COVID-19: HR, 4.48; 95% CI, 4.37-4.59; mortality: HR, 1.12; 95% CI, 1.07-1.16). Black race (HR vs non-Black: HR, 1.25; 95% CI, 1.23-1.28) and Hispanic ethnicity (HR vs non-Hispanic: HR, 1.68; 95% CI, 1.64-1.72) were associated with significantly higher hazards of COVID-19. Although home dialysis was associated with lower COVID-19 rates (HR, 0.77; 95% CI, 0.75-0.80), it was associated with higher mortality (HR, 1.18; 95% CI, 1.11-1.25). Conclusions and Relevance: These results shed light on COVID-19 risk factors and outcomes among Medicare patients receiving long-term chronic dialysis and could inform policy decisions to mitigate the significant extra burden of COVID-19 and death in this population.


Subject(s)
COVID-19/etiology , Kidney Diseases/mortality , Medicare , Renal Dialysis , Aged , COVID-19/epidemiology , COVID-19/mortality , Female , Humans , Kidney Diseases/epidemiology , Kidney Diseases/therapy , Male , Middle Aged , Nursing Homes , Proportional Hazards Models , Retrospective Studies , Risk Factors , SARS-CoV-2 , United States/epidemiology
12.
Emerg Microbes Infect ; 10(1): 578-588, 2021 Dec.
Article in English | MEDLINE | ID: covidwho-1490460

ABSTRACT

Mycobacterium tuberculosis (M. tuberculosis) is the pathogen which causes tuberculosis (TB), a significant human public health threat. Co-infection of M. tuberculosis and the human immunodeficiency virus (HIV), emergence of drug resistant M. tuberculosis, and failure to develop highly effective TB vaccines have limited control of the TB epidemic. Trained immunity is an enhanced innate immune response which functions independently of the adaptive/acquired immune system and responds non-specifically to reinfection with invading agents. Recently, several studies have found trained immunity has the capability to control and eliminate M. tuberculosis infection. Over the past decades, however, the consensus was adaptive immunity is the only protective mechanism by which hosts inhibit M. tuberculosis growth. Furthermore, autophagy plays an essential role in the development of trained immunity. Further investigation of trained immunity, M. tuberculosis infection, and the role of autophagy in this process provide new possibilities for vaccine development. In this review, we present the general characteristics of trained immunity and autophagy. We additionally summarize several examples where initiation of trained immunity contributes to the prevention of M. tuberculosis infection and propose future directions for research in this area.


Subject(s)
Autophagy , Immunity, Innate , Mycobacterium tuberculosis/immunology , Tuberculosis Vaccines/immunology , Tuberculosis/immunology , Tuberculosis/prevention & control , Adaptive Immunity , Animals , Humans , Immunologic Memory , Vaccination
13.
BMC Med Educ ; 21(1): 534, 2021 Oct 18.
Article in English | MEDLINE | ID: covidwho-1477413

ABSTRACT

BACKGROUND: The COVID-19 epidemic affected the career choice of healthcare professionals and students. Career choice regret of healthcare professionals and students during COVID-19 outbreak and its affected factors are largely unexplored. METHODS: Convenience sample of nurses, doctors, and medical students were recruited from hospitals and universities nationwide. The data collected including demographic information, professional value before and after the COVID-19 outbreak, the Connor-Davidson Resilience Scale, and career choice regret level by an online questionnaire. Multinominal logistic regression was employed to explore the factors associated with career choice regret. RESULTS: In total, 9322 participants of convenience sampling were enrolled in, including 5786 nurses, 1664 doctors, and 1872 medical students. 6.7% participants had career choice regret. Multinominal logistic regression analysis showed, compared to participants with no regret, that as levels of psychological resilience increased, the odds of experiencing career choice regret decreased (OR = 0.95, 95% CI 0.94-0.96), while participants with lower professional value evaluation after the COVID-19 outbreak had higher probability to experience career choice regret (OR = 1.55,95% CI 1.50-1.61). Medical students were more likely to regret than nurses (OR = 1.65,95% CI 1.20-2.28), participants whose career/major choice was not their personal ideal had higher risk of experience career choice regret (OR = 1.59,95% CI 1.29-1.96), while participants who were very afraid of the coronavirus had higher risk to experience career choice regret then participants with no fear at all (OR = 2.00,95% CI 1.24-3.21). As for the medical students, results indicated that medical students major in nursing and undergraduates had higher risk to experience career choice regret compared to medical students major in clinical medicine and postgraduate (Master or PhD), with an odds ratios of 2.65(95% CI 1.56-4.49) and 6.85 (95% CI 2.48-18.91)respectively. CONCLUSIONS: A minority of healthcare professionals and medical students regretted their career choices during the COVID-19 outbreak. Enhance personal psychological resilience and professional value would helpful to reduce career choice regret among healthcare professionals and students during pandemic.


Subject(s)
COVID-19 , Students, Medical , Career Choice , China/epidemiology , Cross-Sectional Studies , Delivery of Health Care , Emotions , Humans , SARS-CoV-2
14.
Int Dent J ; 72(2): 236-241, 2022 Apr.
Article in English | MEDLINE | ID: covidwho-1440051

ABSTRACT

OBJECTIVES: This study was performed to examine changes in the number of patient visits and types of oral services in an oral emergency department from the beginning to the control stage of the coronavirus disease 2019 (COVID-19) outbreak in Beijing. METHODS: The numbers of daily oral emergency visits from January 20 to March 24, 2020, at a dental university hospital in Beijing and daily newly confirmed COVID-19 cases in Beijing during the same period were collected and analysed. All oral emergency patient information (including sex, age, and oral diagnosis) was also collected and analysed. Patients with incomplete medical data were excluded. RESULTS: In total, 12,416 patients were included in this study. The number of daily emergency visits was negatively correlated with the number of newly confirmed local COVID-19 cases in Beijing (P < .001). The number of daily emergency visits during the COVID-19 stable period in Beijing was greater than that during the outbreak period (P < .001). Compared to those in the COVID-19 outbreak period, the percentages of females, children and adolescents, patients with acute toothache, and patients with nonurgent cases were higher in the stable period, and the numbers of patients with toothache, trauma, infection, and nonemergency conditions increased in the COVID-19 stable period (P < .001). CONCLUSIONS: COVID-19 significantly influenced the number of patient visits and the percentages of patients with oral emergency situations in the oral emergency department. There were obvious differences in treatment seeking for oral emergencies between the COVID-19 periods in Beijing. There was an inverse relationship between daily oral emergency visits and daily confirmed COVID-19 cases in Beijing.


Subject(s)
COVID-19 , Adolescent , COVID-19/epidemiology , Child , Emergency Service, Hospital , Female , Humans , Retrospective Studies , SARS-CoV-2
15.
Int J Environ Res Public Health ; 18(18)2021 09 16.
Article in English | MEDLINE | ID: covidwho-1409604

ABSTRACT

The COVID-19 epidemic has had a significant impact on society. In particular, it has had a strong impact on college students, including international students. Through an online questionnaire survey, it is found that the psychological distress experienced by international students is the result of a combination of the external environment (including the lockdown measures, social distancing, and social support) and internal factors such as values and behavior. The analysis shows that the new teaching mode and the corresponding changes in learning behavior are significantly associated with the psychological distress brought about by the COVID-19 epidemic. In addition, the influence of international students' values also plays a significant role in their psychological distress. Collective values are conducive to the alleviation of psychological distress, while individual values have the opposite effect. At the same time, the study also reveals that if there is sufficient social support, isolation (due to lockdown or social distancing early or later on) is not necessarily directly related to psychological distress. However, only formal social support can effectively alleviate psychological distress, while informal social support does not play a similar role. These conclusions have certain policy significance for the prevention of and response to epidemics in other countries.


Subject(s)
COVID-19 , Psychological Distress , China/epidemiology , Communicable Disease Control , Humans , Pandemics , SARS-CoV-2 , Students
16.
Protein Cell ; 13(4): 239-257, 2022 04.
Article in English | MEDLINE | ID: covidwho-1384665

ABSTRACT

Studies on diabetes have long been hampered by a lack of authentic disease models that, ideally, should be unlimited and able to recapitulate the abnormalities involved in the development, structure, and function of human pancreatic islets under pathological conditions. Stem cell-based islet organoids faithfully recapitulate islet development in vitro and provide large amounts of three-dimensional functional islet biomimetic materials with a morphological structure and cellular composition similar to those of native islets. Thus, islet organoids hold great promise for modeling islet development and function, deciphering the mechanisms underlying the onset of diabetes, providing an in vitro human organ model for infection of viruses such as SARS-CoV-2, and contributing to drug screening and autologous islet transplantation. However, the currently established islet organoids are generally immature compared with native islets, and further efforts should be made to improve the heterogeneity and functionality of islet organoids, making it an authentic and informative disease model for diabetes. Here, we review the advances and challenges in the generation of islet organoids, focusing on human pluripotent stem cell-derived islet organoids, and the potential applications of islet organoids as disease models and regenerative therapies for diabetes.


Subject(s)
COVID-19 , Diabetes Mellitus , Islets of Langerhans , Diabetes Mellitus/therapy , Humans , Organoids , SARS-CoV-2
17.
J Xray Sci Technol ; 29(5): 741-762, 2021.
Article in English | MEDLINE | ID: covidwho-1359155

ABSTRACT

BACKGROUND AND OBJECTIVE: Monitoring recovery process of coronavirus disease 2019 (COVID-19) patients released from hospital is crucial for exploring residual effects of COVID-19 and beneficial for clinical care. In this study, a comprehensive analysis was carried out to clarify residual effects of COVID-19 on hospital discharged patients. METHODS: Two hundred sixty-eight cases with laboratory measured data at hospital discharge record and five follow-up visits were retrospectively collected to carry out statistical data analysis comprehensively, which includes multiple statistical methods (e.g., chi-square, T-test and regression) used in this study. RESULTS: Study found that 13 of 21 hematologic parameters in laboratory measured dataset and volume ratio of right lung lesions on CT images highly associated with COVID-19. Moderate patients had statistically significant lower neutrophils than mild and severe patients after hospital discharge, which is probably caused by more efforts on severe patients and slightly neglection of moderate patients. COVID-19 has residual effects on neutrophil-to-lymphocyte ratio (NLR) of patients who have hypertension or chronic obstructive pulmonary disease (COPD). After released from hospital, female showed better performance in T lymphocytes subset cells, especially T helper lymphocyte% (16% higher than male). According to this sex-based differentiation of COVID-19, male should be recommended to take clinical test more frequently to monitor recovery of immune system. Patients over 60 years old showed unstable recovery process of immune cells (e.g., CD45 + lymphocyte) within 75 days after discharge requiring longer clinical care. Additionally, right lung was vulnerable to COVID-19 and required more time to recover than left lung. CONCLUSIONS: Criterion of hospital discharge and strategy of clinical care should be flexible in different cases due to residual effects of COVID-19, which depend on several impact factors. Revealing remaining effects of COVID-19 is an effective way to eliminate disorder of mental health caused by COVID-19 infection.


Subject(s)
COVID-19/diagnosis , Patient Discharge/statistics & numerical data , Adolescent , Adult , Aged , Aged, 80 and over , Biomarkers/blood , China , Female , Humans , Longitudinal Studies , Lung/diagnostic imaging , Male , Middle Aged , Retrospective Studies , SARS-CoV-2 , Tomography, X-Ray Computed , Young Adult
19.
Brief Bioinform ; 22(2): 1215-1224, 2021 03 22.
Article in English | MEDLINE | ID: covidwho-1343625

ABSTRACT

The pandemic of coronavirus disease 2019 (COVID-19) urgently calls for more sensitive molecular diagnosis to improve sensitivity of current viral nuclear acid detection. We have developed an anchor primer (AP)-based assay to improve viral RNA stability by bioinformatics identification of RNase-binding site of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA and implementing AP dually targeting the N gene of SARS-CoV-2 RNA and RNase 1, 3, 6. The arbitrarily primed polymerase chain reaction (AP-PCR) improvement of viral RNA integrity was supported by (a) the AP increased resistance of the targeted gene (N gene) of SARS-CoV-2 RNA to RNase treatment; (b) the detection of SARS-CoV-2 RNA by AP-PCR with lower cycle threshold values (-2.7 cycles) compared to two commercially available assays; (c) improvement of the viral RNA stability of the ORF gene upon targeting of the N gene and RNase. Furthermore, the improved sensitivity by AP-PCR was demonstrated by detection of SARS-CoV-2 RNA in 70-80% of sputum, nasal, pharyngeal swabs and feces and 36% (4/11) of urine of the confirmed cases (n = 252), 7% convalescent cases (n = 54) and none of 300 negative cases. Lastly, AP-PCR analysis of 306 confirmed and convalescent cases revealed prolonged presence of viral loading for >20 days after the first positive diagnosis. Thus, the AP dually targeting SARS-CoV-2 RNA and RNase improves molecular detection by preserving SARS-CoV-2 RNA integrity and reveals the prolonged viral loading associated with older age and male gender in COVID-19 patients.


Subject(s)
COVID-19/virology , Polymerase Chain Reaction/methods , Ribonucleases/metabolism , SARS-CoV-2/metabolism , Aged , Binding Sites , Female , Humans , Male , RNA, Viral/genetics , SARS-CoV-2/genetics , SARS-CoV-2/isolation & purification , Viral Load
20.
Sci Rep ; 11(1): 13648, 2021 07 01.
Article in English | MEDLINE | ID: covidwho-1294483

ABSTRACT

Few study has revealed spatial transmission characteristics of COVID-19 in Wuhan, China. We aimed to analyze the spatiotemporal spread of COVID-19 in Wuhan and its influence factors. Information of 32,682 COVID-19 cases reported through March 18 were extracted from the national infectious disease surveillance system. Geographic information system methods were applied to analysis transmission of COVID-19 and its influence factors in different periods. We found decrease in effective reproduction number (Rt) and COVID-19 related indicators through taking a series of effective public health measures including restricting traffic, centralized quarantine and strict stay-at home policy. The distribution of COVID-19 cases number in Wuhan showed obvious global aggregation and local aggregation. In addition, the analysis at streets-level suggested population density and the number of hospitals were associated with COVID-19 cases number. The epidemic situation showed obvious global and local spatial aggregations. High population density with larger number of hospitals may account for the aggregations. The epidemic in Wuhan was under control in a short time after strong quarantine measures and restrictions on movement of residents were implanted.


Subject(s)
COVID-19/epidemiology , Basic Reproduction Number , COVID-19/transmission , China/epidemiology , Disease Outbreaks , Humans , SARS-CoV-2/isolation & purification , Spatio-Temporal Analysis
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