Trophic state assessment of optically diverse lakes using Sentinel-3-derived trophic level index

An accurate estimation of trophic state of lakes with satellite remote sensing is a challenge due to the optical complexity and variability associated with inland waters. Match-up data from 393 sampling stations that has concurrent Sentinel-3 OLCI images were acquired across Wuhan lakes. Trophic Level Index (TLI) algorithms were developed within a global Optical Water Type (OWT) classification system. The performance of algorithms with limited training data gathered by using spectral similarity of highest Sowt was not improved compared with that on basis of no classification. In contrast, using spectral similarity of Sowt > 0.9 rather than the highest Sowt to group more training data with similar traits for each OWT can help build more robust algorithms, which performance is better than that on basis of no classification. Algorithm performance statistics of the test dataset for the stepwise multiple linear regression (SMLR) method were the following: Mean Absolute Error (MAE) = 5.56;Mean Absolute Percentage Error (MAPE) = 11.02 %;Root Mean Square Error (RMSE) = 7.24 and for the back propagation neural network on the basis of the Levenberg-Marquardt-Bayesian regularization algorithm (LMBR-BPNN) method MAE = 4.56;MAPE = 8.33 %;RMSE = 5.98. We detected 8 different OWTs (2,3,4,5,9,10,11,12) in Wuhan lakes and clear spatio-temporal patterns of the trophic state between 2018 and 2020.Our results revealed that the trophic state of Wuhan lakes did not decrease as expected during the COVID-19 lockdown period.

Persistent lymphopenia after diagnosis of COVID-19 predicts acute respiratory distress syndrome: A retrospective cohort study

Background: Lymphopenia is a marker of immunosuppression after severe coronavirus disease-2019 (COVID-19) which is characterized by acute respiratory distress syndrome (ARDS). This study aimed to evaluate the relationships between persistent lymphopenia and ARDS. Methods: A retrospective cohort study of 125 patients with COVID-19 admitted to government-designated treatment center between 14 January 2020, and 20 March 2020 was conducted. We recorded all complete blood cell counts during the day 0th, 3rd, and 7th following the diagnosis of COVID-19. Patients were grouped based on the depression of the lymphocyte cell count, their return, or their failure to normal. The primary outcome was the occurrence of ARDS, and secondary outcomes included developing vital organ dysfunction and hospital lengths of stay. Results: 17.6% (22/125) patients developed ARDS. The lymphocyte counts with ARDS and non-ARDS were 0.94 × 109/L, 1.20 × 109/L at admission, respectively (p = 0.02). On the 3rd and 7th day, the median of lymphocyte count in ARDS was significantly lower than that of non-ARDS. Multivariable logistic regression, which was adjusting for potentially confounding factors (including age, comorbidities, and APACHE II score), showed that persistent lymphopenia within the 7th day was independently associated with ARDS (OR, 3.94 [95% CI, 1.26–12.33, p = 0.018). Further, patients with persistent lymphopenia had longer hospital lengths of stay (p < 0.001). Conclusion: The results showed persistent lymphopenia predicted ARDS after COVID-19. Further studies are needed to investigate whether immunostimulation of lymphocytes within 1 week can reduce ARDS occurrence in patients with COVID-19. [ABSTRACT FROM AUTHOR] Copyright of European Journal of Inflammation (Sage Publications, Ltd.) is the property of Sage Publications, Ltd. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Predicting severe or critical symptoms in hospitalized patients with COVID-19 from Yichang, China.

OBJECTIVES: We aimed to identify potential risk factors for severe or critical coronavirus disease 2019 (COVID-19) and establish a prediction model based on significant factors. METHODS: A total of 370 patients with COVID-19 were consecutively enrolled at The Third People's Hospital of Yichang from January to March 2020. COVID-19 was diagnosed according to the COVID-19 diagnosis and treatment plan released by the National Health and Health Committee of China. Effect-size estimates are summarized as odds ratio (OR) and 95% confidence interval (CI). RESULTS: 326 patients were diagnosed with mild or ordinary COVID-19, and 44 with severe or critical COVID-19. After propensity score matching and statistical adjustment, eight factors were significantly associated with severe or critical COVID-19 (p <0.05) relative to mild or ordinary COVID-19. Due to strong pairwise correlations, only five factors, including diagnostic delay (OR, 95% CI, p: 1.08, 1.02 to 1.17, 0.048), albumin (0.82, 0.75 to 0.91, <0.001), lactate dehydrogenase (1.56, 1.14 to 2.13, 0.011), white blood cell (1.27, 1.08 to 1.50, 0.004), and neutrophil (1.40, 1.16 to 1.70, <0.001), were retained for model construction and performance assessment. The nomogram model based on the five factors had good prediction capability and accuracy (C-index: 90.6%). CONCLUSIONS: Our findings provide evidence for the significant contribution of five independent factors to the risk of severe or critical COVID-19, and their prediction was reinforced in a nomogram model.

Clinical characteristics and outcomes of discharged COVID-19 patients with reoccurrence of SARS-CoV-2 RNA.

AIM: Data are limited on clinical characteristics and outcomes of recovered the 2019 coronavirus disease (COVID-19) patients with the reoccurrence of SARS-CoV-2 RNA. PATIENTS & METHODS: Discharged patients in our hospital were included, who had recovered from COVID-19 with the reoccurrence of SARS-CoV-2 RNA. RESULTS: Six patients were redetectable and positive for SARS-CoV-2 RNA after discharge from 3 to 15 days. The main symptoms, although no fever, included fatigue, dry cough and pharyngeal or chest discomfort, which were generally milder in the repositive period compared with the period of initial infection. Their laboratory indexes were significantly improved compared with the initial infection, and the pulmonary lesions were continuously improving. All close contacts were SARS-CoV-2 RNA-negative. CONCLUSION: No worsening outcomes or active transmission to close contacts were found for the repositive COVID-19 patients.

SARS-CoV-2 clearance in COVID-19 patients with Novaferon treatment: A randomized, open-label, parallel-group trial.

BACKGROUND: The antiviral effects of Novaferon, a potent antiviral protein drug, on COVID-19 was evaluated in the laboratory, and in a randomized, open-label, parallel-group trial. METHODS: In the laboratory, Novaferon's inhibition of viral replication in cells infected with SARS-CoV-2, and prevention of SARS-CoV-2 entry into healthy cells was determined. Antiviral effects of Novaferon in COVID-19 patients with treatment of Novaferon, Novaferon plus Lopinavir/Ritonavir, or Lopinavir/Ritonavir were evaluated. The primary endpoint was the SARS-CoV-2 clearance rates on day six of treatment, and the secondary endpoint was the time to SARS-CoV-2 clearance. RESULTS: Novaferon inhibited viral replication (EC50=1.02ng/ml), and prevented viral infection (EC50=0.10ng/ml). Results from the 89 enrolled COVID-19 patients showed that both Novaferon and Novaferon plus Lopinavir/Ritonavir groups had significantly higher viral clearance rates on day six than Lopinavir/Ritonavir group (50.0% vs. 24.1%, p=0.0400, and 60.0% vs. 24.1%, p=0.0053). The median time to viral clearance was six days, six days, and nine days for three groups, respectively, a 3-day reduction in both the Novaferon and Novaferon plus Lopinavir/Ritonavir groups compared with the Lopinavir/Ritonavir group. CONCLUSIONS: Novaferon exhibited anti-SARS-CoV-2 effects in vitro and in COVID-19 patients. These data justify further evaluation of Novaferon. TRIAL REGISTRATION NUMBER: Number ChiCTR2000029496 at the Chinese Clinical Trial Registry (http://www.chictr.org.cn/).

Clinical Characteristics of Recurrent-positive Coronavirus Disease 2019 after Curative Discharge: a retrospective analysis of 15 cases in Wuhan China (preprint)

In China, the patients with previously negative RT-PCR results again test positive during the post-discharge isolation period. We aimed to determine the clinical characteristics of these recurrent-positive patients. We retrospectively reviewed the data of 15 recurrent-positive patients and 107 control patients with non-recurrent, moderate COVID-19 treated in Wuhan, China. Clinical data and laboratory results were comparatively analyzed. We found that recurrent-positive patients had moderate disease. The rate of recurrent-positive disease in our hospital was 1.87%. Recurrent-positive patients were significantly younger (43(35-54) years) than control patients (60(43-69) years) (P=0.011). The early LOS (length of stay in hospital before recurrence) was significantly longer in recurrent-positive patients (36(34-45) days) than in control patients (15(7-30) days) (P =0.001). The time required for the first conversion of RT-PCR results from positive to negative was significantly longer in recurrent-positive patients (14(10-17) days) than in control patients (6(3-9) days) (P =0.011). Serum COVID-19 antibody levels were significantly lower in recurrent-positive patients than in control patients (IgM: 13.69 {+/-} 4.38 vs. 68.10 {+/-} 20.85 AU/mL, P = 0.015; IgG: 78.53 {+/-} 9.30 vs. 147.85 {+/-} 13.33 AU/mL, P < 0.0001). Recurrent-positive patients were younger than control patients. The early LOS (length of stay in hospital before recurrence) was significantly longer in recurrent-positive group than that in control group. COVID-19 IgM/IgG antibody levels were significantly lower in recurrent-positive group than those in control group, which might explain why the virus RNA RT-PCR was positive after the initial clinical cure(with three times of virus RNA RT-PCR negative). The virus might not be fully eliminated because of the lower IgG level and their later replicating might result in recurrent-positive virus RNA RT-PCR.

Efficacy and safety of chloroquine or hydroxychloroquine in moderate type of COVID-19: a prospective open-label randomized controlled study (preprint)

The outbreak of novel coronavirus disease 2019 (COVID-19) has become a pandemic. Drug repurposing may represent a rapid way to fill the urgent need for effective treatment. We evaluated the clinical utility of chloroquine and hydroxychloroquine in treating COVID-19. Forty-eight patients with moderate COVID-19 were randomized to oral treatment with chloroquine (1000 mg QD on Day 1, then 500 mg QD for 9 days; n=18), hydroxychloroquine (200 mg BID for 10 days; n=18), or control treatment (n=12). Adverse events were mild, except for one case of Grade 2 ALT elevation. Adverse events were more commonly observed in the chloroquine group (44.44%) and the hydroxychloroquine group (50.00%) than in the control group (16.67%). The chloroquine group achieved shorter time to clinical recovery (TTCR) than the control group (P=0.019). There was a trend toward reduced TTCR in the hydroxychloroquine group (P=0.049). The time to reach viral RNA negativity was significantly faster in the chloroquine group and the hydroxychloroquine group than in the control group (P=0.006 and P=0.010, respectively). The median numbers of days to reach RNA negativity in the chloroquine, hydroxychloroquine, and control groups was 2.5 (IQR: 2.0-3.8) days, 2.0 (IQR: 2.0-3.5) days, and 7.0 (IQR: 3.0-10.0) days, respectively. The chloroquine and hydroxychloroquine groups also showed trends toward improvement in the duration of hospitalization and findings on lung computerized tomography (CT). This study provides evidence that (hydroxy)chloroquine may be used effectively in treating moderate COVID-19 and supports larger trials.

RT-PCR Status and Antibody Response in Patients with Coronavirus Disease 2019 (preprint)

Background: Novel coronavirus (COVID-19) is a new viral species that causes pneumonia. Currently, RT-PCR and IgM/IgG antibody assays have been recommended for the diagnosis of COVID-19 infection. However, the correlation between RT-PCR status and antibody (IgG, IgM) response remains unknown. Methods: Consecutive COVID-19 patients admitted to our department between February 10, 2020 and March 10, 2020, were diagnosed by guidelines issued by the World Health Organization (WHO) and included in this study. RT-PCR and antibody (IgM/IgG) assays for COVID-19 infection were performed for all patients according to the manufactures’ protocols. Other data, such as demographic, clinical, laboratory, as well as treatment and outcome, were collected using data collection tables from electronic medical records.Results: During the study period, a total of 103 patients were diagnosed as having a moderate type of COVID-19 at our department, including 55 males and 48 females, with an average age of 57.53 ± 1.65 years old (range 23 to 90 years old). The peak level of SARS-CoV-2 IgM antibody (243.10 ± 89.84 AU/ml) was reported 4 days after the negative RT-PCR (-) (all P < 0.05). Subsequently, the IgM decreased to 42.69 ± 22.39 AU/ml 21 days after RT-PCR (-). However, the IgG was maintained at a high level 4 days before RT-PCR (-) and later. The lymphocyte count was at the lowest level on day7 before the RT-PCR(-) result (P<0.05), and then elevated after RT-PCR conversion (viral clearance).Conclusions: SARS-CoV-2 IgM/IgG levels did not correlate with RT-PCR status in our study sample. We found that SARS-CoV-2 IgM/IgG could be a potential biomarker to monitor clinical course, determine discharge, and assess recovery of those infected patients with the novel coronavirus. Trial registration: A prospective, open label, randomized, control trial for chloroquine or hydroxychloroquine in patients with mild and common novel coronavirus pulmonary (COVIP-19). ChiCTR2000030054. Registered 18 Feb,2020. http://www.chictr.org.cn/edit.aspx?pid=49869&htm=4