User review analysis of dating apps based on text mining.

With the continuous development of information technology, more and more people have become to use online dating apps, and the trend has been exacerbated by the COVID-19 pandemic in these years. However, there is a phenomenon that most of user reviews of mainstream dating apps are negative. To study this phenomenon, we have used topic model to mine negative reviews of mainstream dating apps, and constructed a two-stage machine learning model using data dimensionality reduction and text classification to classify user reviews of dating apps. The research results show that: firstly, the reasons for the current negative reviews of dating apps are mainly concentrated in the charging mechanism, fake accounts, subscription and advertising push mechanism and matching mechanism in the apps, proposed corresponding improvement suggestions are proposed by us; secondly, using principal component analysis to reduce the dimensionality of the text vector, and then using XGBoost model to learn the low-dimensional data after oversampling, a better classification accuracy of user reviews can be obtained. We hope These findings can help dating apps operators to improve services and achieve sustainable business operations of their apps.

Research of mortality risk prediction based on hospital admission data for COVID-19 patients.

As COVID-19 continues to spread across the world and causes hundreds of millions of infections and millions of deaths, medical institutions around the world keep facing a crisis of medical runs and shortages of medical resources. In order to study how to effectively predict whether there are risks of death in patients, a variety of machine learning models have been used to learn and predict the clinical demographics and physiological indicators of COVID-19 patients in the United States of America. The results show that the random forest model has the best performance in predicting the risk of death in hospitalized patients with COVID-19, as the COVID-19 patients' mean arterial pressures, ages, C-reactive protein tests' values, values of blood urea nitrogen and their clinical troponin values are the most important implications for their risk of death. Healthcare organizations can use the random forest model to predict the risks of death based on data from patients admitted to a hospital due to COVID-19, or to stratify patients admitted to a hospital due to COVID-19 based on the five key factors this can optimize the diagnosis and treatment process by appropriately arranging ventilators, the intensive care unit and doctors, thus promoting the efficient use of limited medical resources during the COVID-19 pandemic. Healthcare organizations can also establish databases of patient physiological indicators and use similar strategies to deal with other pandemics that may occur in the future, as well as save more lives threatened by infectious diseases. Governments and people also need to take action to prevent possible future pandemics.

Experience of the homecare of children on automatic peritoneal dialysis during the COVID-19 outbreak: A qualitative descriptive study.

AIMS: To describe the home care experience, challenges and coping strategies of caregivers with children on automatic peritoneal dialysis (PD) in mainland China during the early stage of the COVID-19 outbreak. DESIGN: A qualitative descriptive approach was adopted. Semi-structured telephone interviews were conducted among 14 families with children on automatic peritoneal dialysis from February 2nd to 10th, 2020. The care routine, stress and coping strategies of caregivers of children on peritoneal dialysis were collected. The data were analysed using thematic analysis. METHODS: Four key themes were defined: (1) concerns about PD treatment intertwined with worries about COVID-19; (2) retaining a sense of normality in the middle of the challenges; (3) staying safe; and (4) staying positive and carrying on. RESULTS: Families with children on automatic PD addressed the stress from COVID-19 and its containment measures by closely adhering to COVID-19 preventative measures, actively adjusting mentality and maintaining a sense of normality during the outbreak. This implies that healthcare staff need to be more aware of the complex medical needs of families with children on automatic PD, advocate for them and facilitate their navigation through the repurposed healthcare system.

Psychological research of the children with chronic kidney disease and their guardians during the COVID-19 pandemic.

Background: There is great mental stress due to the coronavirus disease 2019 (COVID-19) pandemic. However, there are no detailed psychological studies of the children with chronic kidney disease (CKD) and their guardians during the COVID-19 pandemic. Objective: This study explores the psychological pressure on children with CKD and their guardians. Methods: An online survey was conducted at 20 of the largest pediatric nephropathy departments in China, including the Rutter Parent Questionnaire, Self-rating Anxiety Scale (SAS), and Self-rating Depression Scale (SDS). Overall, 885 children (589 children with CKD associated with 296 children of the control group) completed the survey together with their guardians. Results: There was no statistical difference between CKD children and control children regarding their Rutter behavior scores and abnormal behaviors. Nevertheless, the abnormal behavior of children might aggravate the anxiety and depression of guardians in both CKD and control groups (p < 0.05). We confirmed that the anxiety and depression of guardians in the CKD group were both significantly higher than those in the control group (p < 0.05). The guardians in the CKD group with lower annual income were more likely to experience anxiety (p < 0.05). Furthermore, the guardians whose children were older than 11 years old might be more anxious than those who were 6-11 years old. Besides, the guardians in the CKD group who watched the news for 30-60 min daily were less likely to have depression than those who watched < 10 min (p < 0.05). The subgroup results showed that the gender, the time of watching the news, the annual income of guardians, and children's age might be the most critical factors influencing guardians' psychological burden. Conclusion: The guardians in the CKD group have more severe anxiety and depression during the pandemic. The children's abnormal behavior, adolescents' pressure, low household income, and the panic about the pandemic may be the main reasons for the anxiety and depression of guardians.

Pharmacokinetics and Metabolism of Traditional Chinese Medicine in the Treatment of COVID-19.

BACKGROUND: The outbreak of coronavirus disease 19 (COVID-19) has caused great concern to public health. Convincing clinical experiences showed that traditional Chinese medicine (TCM) has exhibited remarkable efficacy in the prevention, treatment and rehabilitation of COVID-19. The research on the treatment of COVID-19 disease with TCM mainly focused on the pharmacological effects and mechanistic analysis. However, the TCM's pharmacokinetics and potential herb-drug interaction in the treatment of COVID-19 are currently unclear. METHODS: This review summarizes the pharmacokinetics and characteristics of cytochrome P450 enzyme (CYP450) metabolism of TCM recommended in the Guidelines for diagnosis and treatment of coronavirus disease 2019 (trial version eighth), and meanwhile analyzes the potential interactions between TCM and western medicine. RESULTS: The pharmacokinetics of TCM mainly focused on preclinical pharmacokinetics, and fewer clinical pharmacokinetics research was reported. When TCM and western are both metabolized by CYP450 and coadministered, a potential herb-drug interaction might occur. CONCLUSION: Knowledge of the pharmacokinetics and metabolism of TCM is key to understanding rational TCM use of COVID-19 and developing antiviral TCM.

An internet-based multidisciplinary online medical consultation system to help cope with pediatric medical needs during the COVID-19 outbreak: a cross-sectional study.

BACKGROUND: Telemedicine is becoming an emerging innovative supplement to the traditional medical system in China. In the present study, we described the rapid implementation of the telemedicine in pediatrics during the coronavirus disease 2019 (COVID-19) outbreak and explored its value in response to the demand for pediatric medical services during the epidemic. METHODS: An Internet-based platform for multidisciplinary online medical consultation was established on February 8, 2020, by a national children's medical center in China. The medical data of the traditional hospital visits and novel online visits from the first two months (February 8 to March 31) after the establishment of the platform were collected and analyzed. The demographic features, changes in the disease spectrum and characteristics of online medical services were described. RESULTS: The total number of visits was significantly lower (by 75.3%) than that of in the same period in the previous year. The disease spectrum was different with a significant decrease of >95% in the number of patients with infectious or contagious diseases. The online visits accounted for 14.7% of all visits. Online patients came from all over the country, covering 91% of the administrative regions of China, and the largest proportion of inquiries were for infants (33.7%) (P<0.01). The response rate of experts to requests for online consultations was 100%. During the study period, 266 experts from 25 pediatric specialties completed 12,318 effective consultations, proving different degrees of online supplementation for various specialties (4.3-168.4%). Online consultations mainly addressed two types of problems: (I) accessibility of the traditional hospital visits and (II) consultations regarding an illness. Data from pediatric nephrology showed that 96% of the patients with stable chronic kidney disease successfully received follow-up medication adjustment guidance through the online platform. CONCLUSIONS: The traditional hospital medical services have been affected by the COVID-19 outbreak. The multidisciplinary online medical consultation system is a strategy to actively respond to the medical needs of children during unique periods.

Stance markers in English medical research articles and newspaper opinion columns: A comparative corpus-based study.

Stance markers are critical linguistic devices for writers to convey their personal attitudes, judgments or assessments about the proposition of certain messages. Following Hyland's framework of stance, this study investigated the distribution of stance markers in two different genres: medical research articles (medical RA) and newspaper opinion columns (newspaper OC). The corpus constructed for the investigation includes 52 medical research articles and 175 newspaper opinion articles, which were both written in English and published from January to April in 2020 with the topic focusing on COVID-19. The findings of this study demonstrated that the occurrences of stance markers in newspaper OC were far more frequent than those in medical RA, indicating the different conventions of these two genres. Despite the significant difference in the occurrences of stance markers between the two sub-corpora, similarities of the most frequent stance markers in two genres were also highlighted. The study indicated that the topic content seems to play an important role in shaping the way of how writers construct their stance. The lack of information or evidence on the topic of COVID-19 could restrain writers from making high degree of commitment to their claims, which make them adopt a more tentative stance to qualify their statements.

Sub10 μm macroporous aramid substrates with a hierarchically structured interface for organic solvent nanofiltration

Compared with traditional methods for elaborately tailoring the active layer of thin-film composite (TFC) membranes, this study focused on building novel substrates for potential applications in developing organic solvent nanofiltration (OSN) membranes. One kind of “three-parts” hierarchically structured interface with nanospheres and macro surface pores was successfully prepared via Michael addition and Schiff's base (M&S) reactions between N-(2-aminoethyl)-3-aminopropyl triethoxysilane (NAE-A) and glycerite (a natural polyphenol) in the aramid substrate. The thickness was reduced to sub10 μm with the aid of the high-speed spin coating process coupling nonsolvent-induced phase separation (HSSC-co-NIPS) method. The composition characterization results demonstrated the introduction of glycerite, and the reactions occurred in/on the substrate. Scanning electron microscopy (SEM) images clearly showed that the sub10 μm substrate contained a “three-level” hierarchically structured interface that included: (1) a “stalk-like” structure;(2) glycerite-NAE-A silane (GNAS) nanospheres;and (3) the substrate surface. These phenomena also resulted in better surface hydrophilicity. All types of organic solvents, including harsh solvents, such as tetrahydrofuran (THF) and N,N-dimethylformamide (DMF), had stable permeability within the substrate, as did apolar n-hexane and isopar™ G. Therefore, the as-prepared TFC OSN membrane, which had an extremely short polymerization time, retained broad-spectrum solvent stability and had the highest solvent permeance in acetonitrile (24.5 ± 0.4 L m−2 h−1·bar−1). In addition, the resultant TFC membrane almost completely rejected the popular macrolide antibiotic azithromycin (AZM, 748.98 g mol−1) in ethanol, which is used to treat COVID-19.

Analysis of inflammatory parameters and disease severity for 88 hospitalized COVID-19 patients in Wuhan, China.

Background and aim: The outbreak of coronavirus disease 2019 (COVID-19) is quickly turning into a pandemic. We aimed to further clarify the clinical characteristics and the relationship between these features and disease severity. Methods: In this retrospective single-center study, demographic, clinical and laboratory data were collected and analyzed among moderate, severe and critically ill group patients. Results: 88 hospitalization patients confirmed COVID-19 were enrolled in this study. The average age of the patients was 57.11 years (SD, ±15.39). Of these 88 patients, the median body mass index (BMI) was 24.03 (IQR, 21.64-26.61; range 15.05-32.39), the median duration from disease onset to hospital admission were 11 days (IQR, 6.50-14.50). 46.59% patients had one or more comorbidities, with hypertension being the most common (26.14%), followed by diabetes mellitus (12.50%) and coronary atherosclerotic heart disease (CAD) (7.95%). Common symptoms at onset of disease were fever (71.59%), cough (59.09%), dyspnea (38.64%) and fatigue (29.55%). 88 patients were divided into moderate (47 [53.41%]), severe (32 [36.36%]) and critically ill (9 [10.23%]) groups. Compared with severe and moderate patients, lymphocytopenia occurred in 85.71% critically ill patients, and serum IL-2R, IL-6, IL-8, TNF-α, LDH, and cTnI were also increased in 71.42%, 83.33%, 57.14%, 71.43%, 100% and 42.86% in critically ill patients. Through our analysis, the age, comorbidities, lymphocyte count, eosinophil count, ferritin, CRP, LDH, PT and inflammatory cytokines were statistically significant along with the disease severity. Conclusion: We found some clinical characteristic and inflammatory cytokines could reveal the severity of COVID-19 during the outbreak phage. Our research could assist the clinicians recognize severe and critically ill patients timely and focus on the expectant treatment for each patient.

COVID-19 Outbreak and Management Approach for Families with Children on Long-Term Kidney Replacement Therapy.

BACKGROUND AND OBJECTIVES: During the coronavirus disease 2019 outbreak, the treatment of families with children on long-term KRT is challenging. This study was conducted to identify the current difficulties, worries regarding the next 2 months, and mental distress experienced by families with children on long-term KRT during the coronavirus disease 2019 outbreak and to deliver possible management approaches to ensure uninterrupted treatment for children on long-term KRT. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: A multicenter online survey was conducted between February 10 and 15, 2020, among the families with children on long-term KRT from five major pediatric dialysis centers in mainland China. The primary caregivers of children currently on long-term KRT were eligible and included. Demographic information, severe acute respiratory syndrome coronavirus 2 infection status, current difficulties, and worries regarding the next 2 months were surveyed using a self-developed questionnaire. The Patient Health Questionnaire-9 and the General Anxiety Disorder Scale-7 were used to screen for depressive symptoms and anxiety, respectively. RESULTS: Among the children in the 220 families included in data analysis, 113 (51%) children were on dialysis, and the other 107 (49%) had kidney transplants. No families reported confirmed or suspected cases of coronavirus disease 2019. Overall, 135 (61%) and 173 (79%) caregivers reported having difficulties now and having worries regarding the next 2 months, respectively. Dialysis supply shortage (dialysis group) and hard to have blood tests (kidney transplantation group) were most commonly reported. A total of 29 (13%) caregivers had depressive symptoms, and 24 (11%) had anxiety. After the survey, we offered online and offline interventions to address their problems. At the time of the submission of this paper, no treatment interruption had been reported. CONCLUSIONS: The coronavirus disease 2019 outbreak has had physical, mental, logistical, and financial effects on families with children on long-term KRT.

Early viral clearance and antibody kinetics of COVID-19 among asymptomatic carriers (preprint)

BackgroundAsymptomatic carriers contribute to the spread of Coronavirus Disease 2019 (COVID-19), but their clinical characteristics, viral kinetics, and antibody responses remain unclear. MethodsA total of 56 COVID-19 patients without symptoms at admission and 19 age-matched symptomatic patients were enrolled. RNA of SARS-CoV-2 was tested using transcriptase quantitative PCR, and the total antibodies (Ab), IgG, IgA and IgM against the SARS-CoV-2 were tested using Chemiluminescence Microparticle Immuno Assay. ResultsAmong 56 patients without symptoms at admission, 33 cases displayed symptoms and 23 remained asymptomatic throughout the follow-up period. 43.8% of the asymptomatic carriers were children and none of the asymptomatic cases had recognizable changes in C-reactive protein or interleukin-6, except one 64-year-old patient. The initial threshold cycle value of nasopharyngeal SARS-CoV-2 in asymptomatic carriers was similar to that in pre-symptomatic and symptomatic patients, but the communicable period of asymptomatic carriers (9.63 days) was shorter than pre-symptomatic patients (13.6 days). There was no obvious differences of the seropositive conversion rate of total Ab, IgG, and IgA among the three groups, though the rates of IgM varied largely. The average peak IgG and IgM COI of asymptomatic cases was 3.5 and 0.8, respectively, which is also lower than those in symptomatic patients with peaked IgG and IgM COI of 4.5 and 2.4 (p <0.05). ConclusionYoung COVID-19 patients seem to be asymptomatic cases with early clearance of SARS-CoV-2 and low levels of IgM generation but high total Ab, IgG and IgA. Our findings provide empirical information for viral clearance and antibody kinetics of asymptomatic COVID-19 patients.

Consensus recommendations for the care of children receiving chronic dialysis in association with the COVID-19 epidemic.

Coronavirus disease 2019 (COVID-19) has rapidly spread not only in China but throughout the world. Children with kidney failure (chronic kidney disease (CKD) stage 5) are at significant risk for COVID-19. In turn, a set of recommendations for the prevention and control of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and COVID-19 in pediatric hemodialysis (HD) centers and in home peritoneal dialysis (PD) settings have been proposed. The recommendations are based on the epidemiological features of the SARS-CoV-2 virus and COVID-19 disease, susceptibility factors, and preventive and control strategies. These recommendations will be updated as new information regarding SARS-CoV-2 and COVID-19 becomes available.

Clinical characteristics of the recovered COVID-19 patients with re-detectable positive RNA test (preprint)

Background It has been reported that several cases recovered from COVID-19 tested positive for SARS-CoV-2 after discharge (re-detectable positive, RP), however the clinical characteristics, significance and potential cause of RP patients remained elusive. Methods A total of 262 COVID-19 patients were discharged from January 23 to February 25, 2020, and were enrolled for analysis of their clinical parameters. The RP and non-RP (NRP) patients were grouped according to the disease severity during their hospitalization period. The clinical characterization at re-admission to the hospital was analyzed. SARS-CoV-2 RNA and plasma antibody levels were detected using high-sensitive detection methods. Findings Up to March 10, 2020, all of patients were followed up for at least 14 days, and 38/262 of RP patients (14.5%) were present. The RP patients were characterized by being less than 14-years old and having mild and moderate conditions as compared to NRP patients, while no severe patients became RP. Retrospectively, the RP patients displayed fewer symptoms, more sustained remission of CT imaging and earlier RNA negative-conversion but similar plasma antibody levels during their hospitalization period as compared to those NRP patients. When re-admitted to the hospital, these RP patients showed no obvious clinical symptoms or disease progression indicated by normal or improving CT imaging and inflammatory cytokine levels. All 21 close contacts of RP patients were tested negative for SARS-CoV-2 RNA, and no suspicious clinical symptoms were reported. However, 18/24 of RNA-negative samples detected by the commercial kit were tested to be positive for virus RNA using a hyper-sensitive method, suggesting the carrier status of virus possibly existed in patients recovered from COVID-19. Interpretation Our results showed that young and mild COVID-19 patients seem to be RP patients after discharge, who show no obviously clinical symptoms and disease progression upon re-admission. More sensitive RNA detection methods are required to monitor these patients during follow-up. Our findings provide empirical information and evidence for the effective management of COVID-19 patients during their convalescent phase.

Antibody responses to SARS-CoV-2 in patients of novel coronavirus disease 2019 (preprint)

Summary Background The novel coronavirus SARS-CoV-2 is a newly emerging virus. The antibody response in infected patient remains largely unknown, and the clinical values of antibody testing have not been fully demonstrated. Methods A total of 173 patients with confirmed SARS-CoV-2 infection were enrolled. Their serial plasma samples (n = 535) collected during the hospitalization period were tested for total antibodies (Ab), IgM and IgG against SARS-CoV-2 using immunoassays. The dynamics of antibodies with the progress and severity of disease was analyzed. Findings Among 173 patients, the seroconversion rate for Ab, IgM and IgG was 93.1% (161/173), 82.7% (143/173) and 64.7% (112/173), respectively. Twelve patients who had not seroconverted were those only blood samples at the early stage of illness were collected. The seroconversion sequentially appeared for Ab, IgM and then IgG, with a median time of 11, 12 and 14 days, respectively. The presence of antibodies was < 40% among patients in the first 7 days of illness, and then rapidly increased to 100.0%, 94.3% and 79.8% for Ab, IgM and IgG respectively since day 15 after onset. In contrast, the positive rate of RNA decreased from 66.7% (58/87) in samples collected before day 7 to 45.5% (25/55) during days 15 to 39. Combining RNA and antibody detections significantly improved the sensitivity of pathogenic diagnosis for COVID-19 patients (p < 0.001), even in early phase of 1-week since onset (p = 0.007). Moreover, a higher titer of Ab was independently associated with a worse clinical classification (p = 0.006). Interpretation The antibody detection offers vital clinical information during the course of SARS-CoV-2 infection. The findings provide strong empirical support for the routine application of serological testing in the diagnosis and management of COVID-19 patients.