The role of air pollution in fetal origins of childhood allergy: Challenges and opportunities

Allergic disease is still a serious global public health problem, affecting 30-40% of world population. The rapid increase in prevalence indicates gene-by-environment interaction, in which epigenetics may be the underlying mechanism. We reviewed recent epidemiological studies about the association between prenatal exposure to air pollution and childhood allergies. On the other hand, we reviewed the evidence that maternal exposure to air pollution caused epigenetic alterations that changed the gene expression or transcription in offspring. We further discussed the challenges of the global warming and COVID-19 to the childhood allergies especially in developing countries, and suggested the opportunities to prevention or control by early intervention, immunotherapy, and epigenetic therapy.

Protein nanopore reveals the renin-angiotensin system crosstalk with single-amino-acid resolution.

The discovery of crosstalk effects on the renin-angiotensin system (RAS) is limited by the lack of approaches to quantitatively monitor, in real time, multiple components with subtle differences and short half-lives. Here we report a nanopore framework to quantitatively determine the effect of the hidden crosstalk between angiotensin-converting enzyme (ACE) and angiotensin-converting enzyme 2 (ACE2) on RAS. By developing an engineered aerolysin nanopore capable of single-amino-acid resolution, we show that the ACE can be selectively inhibited by ACE2 to prevent cleavage of angiotensin I, even when the concentration of ACE is more than 30-fold higher than that of ACE2. We also show that the activity of ACE2 for cleaving angiotensin peptides is clearly suppressed by the spike protein of SARS-CoV-2. This leads to the relaxation of ACE and the increased probability of accumulation of the principal effector angiotensin II. The spike protein of the SARS-CoV-2 Delta variant is demonstrated to have a much greater impact on the crosstalk than the wild type.

Old Age is an Independent Risk Factor for Pneumonia Development in Patients with SARS-CoV-2 Omicron Variant Infection and a History of Inactivated Vaccine Injection.

Objective: Analyzing the risk factors for pneumonia development in breakthrough cases with a history of inactivated vaccine injection is important. The present study aimed to investigate the risk factors for pneumonia development during Omicron variant infection. Design and Methods: The clinical data were retrospectively collected from 187 patients who previously received inactivated vaccine and were infected by the Omicron variant. Results: Among the 187 patients, 73 had 2 doses of inactivated vaccine injection and the remaining 114 had 3 doses; 19 patients had pneumonia at admission. The univariate logistic analysis showed that age, baseline platelet count, D-dimer level, and CD8+ T lymphocyte count were associated with pneumonia development at admission. The multivariate analysis showed that only age was the independent risk factor for pneumonia development (odds ratio = 1.046, 95% confidence interval: 1.003-1.091, P = 0.04). With an optimal cutoff value of 46, 4.4% (4/91) patients in the age <46 years group and 15.63% (15/96) patients in the age ≥46 years group had pneumonia (χ 2 = 6.454, P = 0.01). Moreover, age negatively correlated with CD8+ T cell count, B cell count, and albumin and uric acid levels (all P < 0.01), while age positively correlated with the glucose level (P < 0.01). Conclusion: Old age was the only independent risk factor for pneumonia development in patients with Omicron variant infection and a history of inactivated vaccine injection.

SARS-CoV-2 omicron variant clearance delayed in breakthrough cases with elevated fasting blood glucose.

BACKGROUND: Omicron variant (B.1.1.529) is a dominant variant worldwide. However, the risk factors for Omicron variant clearance are yet unknown. The present study aimed to investigate the risk factors for early viral clearance of Omicron variant in patients with a history of inactivated vaccine injection. METHODS: Demographic, clinical, and epidemiological data from 187 patients were collected retrospectively during the Omicron variant wave. RESULTS: 73/187 and 114/187 patients were administered two and three doses of vaccine, respectively. The median duration of SARS-CoV-2 RNA positivity was 9 days, and the difference between patients with two and three vaccine injections was insignificant (P = 0.722). Fever was the most common symptom (125/187), and most patients (98.4%) had a fever for < 7 days. The RNA was undetectable in 65/187 patients on day 7. Univariable logistic analysis showed that baseline glucose, uric acid, lymphocytes count, platelet count, and CD4+ T lymphocyte count were associated with SARS-CoV-2 RNA-positivity on day 7. Multivariable analysis showed that glucose ≥ 6.1 mmol/L and CD4+T lymphocytes count were independent risk factors for RNA positivity on day 7. 163/187 patients had an undetectable RNA test on day 14, and uric acid was the only independent risk factor for RNA positivity. Moreover, baseline glucose was negatively correlated with uric acid and CD4+ and CD8+ T cell count, while uric acid was positively correlated with CD4+ and CD8+ T cell count. CONCLUSIONS: Omicron variant clearance was delayed in breakthrough cases with elevated fasting blood glucose, irrespective of the doses of inactivated vaccine.

Clinical characteristics and factors influencing development of a pulmonary fungal infection in patients with severe respiratory diseases

Objectives: To examine the clinical characteristics, drug resistance, and factors influencing development of a pulmonary fungal infection in patients with severe respiratory diseases in order to provide a reference for clinical treatment.

Accurate virus identification with interpretable Raman signatures by machine learning.

Rapid identification of newly emerging or circulating viruses is an important first step toward managing the public health response to potential outbreaks. A portable virus capture device, coupled with label-free Raman spectroscopy, holds the promise of fast detection by rapidly obtaining the Raman signature of a virus followed by a machine learning (ML) approach applied to recognize the virus based on its Raman spectrum, which is used as a fingerprint. We present such an ML approach for analyzing Raman spectra of human and avian viruses. A convolutional neural network (CNN) classifier specifically designed for spectral data achieves very high accuracy for a variety of virus type or subtype identification tasks. In particular, it achieves 99% accuracy for classifying influenza virus type A versus type B, 96% accuracy for classifying four subtypes of influenza A, 95% accuracy for differentiating enveloped and nonenveloped viruses, and 99% accuracy for differentiating avian coronavirus (infectious bronchitis virus [IBV]) from other avian viruses. Furthermore, interpretation of neural net responses in the trained CNN model using a full-gradient algorithm highlights Raman spectral ranges that are most important to virus identification. By correlating ML-selected salient Raman ranges with the signature ranges of known biomolecules and chemical functional groups­for example, amide, amino acid, and carboxylic acid­we verify that our ML model effectively recognizes the Raman signatures of proteins, lipids, and other vital functional groups present in different viruses and uses a weighted combination of these signatures to identify viruses.

Erratum to the effect of RAS blockers on the clinical characteristics of COVID-19 patients with hypertension.

[This corrects the article DOI: 10.21037/atm.2020.03.229.].

Prevalence and Associated Factors for Elevated Depressive Symptoms in 386,924 Primary Students during the COVID-19 Pandemic Normalization in China.

We aimed to assess the prevalence of elevated depressive symptoms and its associated factors during the coronavirus disease 2019 (COVID-19) pandemic among primary students in China. We included 386,924 students aged 6-12 years from three cities in Henan province, China, over the period 21-27 May 2021. The overall prevalence of depressive symptoms was 5.8%. Participants with high depressive symptoms were more likely to be senior urban primary students, and exhibited an insignificant increase in hand washing frequency, non-mask wearing behavior, higher error rates of cognition tests, and greater levels of worry and fear. The associated factors for high depressive symptoms were found to include age, sex, grade, location, worry level, fear level, cognitive status, and change in lifestyle after gaining knowledge about COVID-19. Our results suggest that governments need to focus on factors affecting the mental health of school-age children while combating COVID-19, as it would facilitate better decision making on the international and national level.

The impact of weather condition and social activity on COVID-19 transmission in the United States.

The coronavirus disease 2019 (COVID-19) has been first reported in December 2019 and rapidly spread worldwide. As other severe acute respiratory syndromes, it is a widely discussed topic whether seasonality affects the COVID-19 infection spreading. This study presents two different approaches to analyse the impact of social activity factors and weather variables on daily COVID-19 cases at county level over the Continental U.S. (CONUS). The first one is a traditional statistical method, i.e., Pearson correlation coefficient, whereas the second one is a machine learning algorithm, i.e., random forest regression model. The Pearson correlation is analysed to roughly test the relationship between COVID-19 cases and the weather variables or the social activity factor (i.e. social distance index). The random forest regression model investigates the feasibility of estimating the number of county-level daily confirmed COVID-19 cases by using different combinations of eight factors (county population, county population density, county social distance index, air temperature, specific humidity, shortwave radiation, precipitation, and wind speed). Results show that the number of daily confirmed COVID-19 cases is weakly correlated with the social distance index, air temperature and specific humidity through the Pearson correlation method. The random forest model shows that the estimation of COVID-19 cases is more accurate with adding weather variables as input data. Specifically, the most important factors for estimating daily COVID-19 cases are the population and population density, followed by the social distance index and the five weather variables, with temperature and specific humidity being more critical than shortwave radiation, wind speed, and precipitation. The validation process shows that the general values of correlation coefficients between the daily COVID-19 cases estimated by the random forest model and the observed ones are around 0.85.

Efficacy and Safety of Washed Microbiota Transplantation to Treat Patients with Mild-to-Severe COVID-19 and Suspected of Having Gut Microbiota Dysbiosis: Study Protocol for a Randomized Controlled Trial.

OBJECTIVE: Coronavirus disease 2019 (COVID-19) is often accompanied by gastrointestinal symptoms, which are related to gut microbiota dysbiosis (GMD). Whether washed microbiota transplantation (WMT) is an effective treatment for COVID-19 patients suspected of having GMD by restoring the gut microbiota is unknown. This study is designed to explore the efficacy and safety of WMT in COVID-19 patients suspected of having GMD. METHODS: This is a randomized, multicenter, single-blind prospective study. COVID-19 patients suspected of having GMD will be randomly divided to receive routine treatment only or to receive routine treatment and WMT. The frequency of WMT will be once a day for three consecutive days. Laboratory and imaging examinations will be performed at admission, 1 and 2 weeks after treatment, and on the day of discharge. Then a telephone follow-up will be conducted at 1st week, 2nd week, and 6th month after discharge. The clinical efficacy and safety of WMT in COVD-19 patients suspected of having GMD and the effects of WMT on the organ function, homeostasis, inflammatory response, intestinal mucosal barrier function, and immunity of the patients will be evaluated. RESULTS: By following the proposed protocol, WMT is expected to be efficacious and safe for the treatment of COVID-19 patients suspected of having GMD, and the therapeutic effect is expected to be associated with improvement of the intestinal mucosal barrier function, inflammatory response, and immunity. CONCLUSION: The findings from this study may offer a new approach for the prevention and treatment of COVID-19 patients suspected of having GMD.

Delayed SARS-CoV-2 Clearance in Patients with Obesity.

OBJECTIVE: The present study aimed to investigate the correlation between obesity and virus persistence in patients with COVID-19. DESIGN AND METHODS: A total of 57 patients with laboratory-confirmed COVID-19 were admitted to two clinical centers, and data were analyzed retrospectively. Among them, 18 patients with body mass index (BMI) ≥ 25 kg/m2 were diagnosed with obesity, and dynamics of viral replication were compared. RESULTS: Eighteen patients were diagnosed with obesity. The correlations between BMI and white blood cell, C-reactive protein, and cycle threshold (Ct) values of ORF1ab were not significant (all P > 0.05). On day 7 after admission, virus clearance was achieved in 13 (33.3%) patients with BMI < 25 kg/m2 and 5 (27.8%) patients with BMI ≥ 25 kg/m2 (χ2 = 0.176, P =0.68). On day 14, the RNA tests were negative in 37 (94.9%) patients with BMI < 25 kg/m2 and 13 (72.2%) patients with BMI ≥ 25 kg/m2 (χ2 = 5.865, P = 0.03). Multivariable analysis showed that only BMI ≥ 25 kg/m2 (P = 0.02) was the independent risk factor for virus clearance on day 14. CONCLUSION: Obesity may affect the clearance of SARS-CoV-2, and BMI should be assessed in patients with COVID-19, although they are not seriously ill.

The papain-like protease of coronaviruses cleaves ULK1 to disrupt host autophagy.

The ongoing pandemic of COVID-19 alongside the outbreaks of SARS in 2003 and MERS in 2012 underscore the significance to understand betacoronaviruses as a global health challenge. SARS-CoV-2, the etiological agent for COVID-19, has infected over 50 million individuals' worldwide with more than ∼1 million fatalities. Autophagy modulators have emerged as potential therapeutic candidates against SARS-CoV-2 but recent clinical setbacks urge for better understanding of viral subversion of autophagy. Using MHV-A59 as a model betacoronavirus, time-course infections revealed significant loss in the protein level of ULK1, a canonical autophagy-regulating kinase, and the concomitant appearance of a possible cleavage fragment. To investigate whether virus-encoded proteases target ULK1, we conducted in-vitro and cellular cleavage assays and identified ULK1 as a novel bona fide substrate of SARS-CoV-2 papain-like protease (PLpro). Mutagenesis studies discovered that ULK1 is cleaved at a conserved PLpro recognition sequence (LGGG) after G499, separating its N-terminal kinase domain from a C-terminal substrate recognition region. Over-expression of SARS-CoV-2 PLpro is sufficient to impair starvation-induced autophagy and disrupt formation of ULK1-ATG13 complex. Finally, we demonstrated a dual role for ULK1 in MHV-A59 replication, serving a pro-viral functions during early replication that is inactivated at late stages of infection. In conclusion, our study identified a new mechanism by which PLpro of betacoronaviruses induces viral pathogenesis by targeting cellular autophagy.

Treatment of COVID-19 patients suspected with gut microbiota dysbiosis with washed microbiota transplantation: study protocol for a randomized controlled trial (preprint)

BACKGROUND: Coronavirus disease 2019 (COVID-19) is often accompanied by gastrointestinal symptoms, which is related to gut microbiota dysbiosis (GMD). Whether washed microbiota transplantation (WMT) is effective in COVID-19 patients suspected with GMD by restoring gut microbiota is unknown. This study is designed to explore the efficacy and safety of WMT in COVID-19 patients suspected with GMD.METHODS: COVID-19 patients suspected with GMD will be randomly divided to receive routine treatment (group A) or receive routine treatment and WMT (group B). The frequency of WMT will be once a day for three consecutive days. Nucleic acid test, imaging examination, and tests related to organ functions, homeostasis, inflammatory response, intestinal barrier function and immunity will be performed at admission, 1, and 2 weeks after treatment and on the day of discharge. The clinical efficacy and safety of WMT in COVD-19 suspected with GMD and the effects of WMT on the organ function, homeostasis, inflammatory response, intestinal barrier function and immunity of the patients will be evaluated. The primary outcome will be the clinical efficacy, as reflected by the SARS-Cov-2 infection status, gastrointestinal symptoms and the recovery of the disease. The secondary outcomes will be the effects of WMT on the organ function, homeostasis, inflammatory response, intestinal barrier function and immunity of the patients, as well as occurrence of adverse events during WMT.DISCUSSION: In the proposed protocol, WMT is expected to be efficacious and safe for the treatment of COVID-19 patients suspected with GMD, and the therapeutic effect is expected to be associated with the improvement of intestinal barrier function, inflammatory response and immunity. Findings from this study may open up a new way for the prevention and treatment of COVID-19 suspected with GMD.TRIAL REGISTRATION: Chinese Clinical Trial Registry – URL: http://www.chictr.org.cn/index.aspx. Registration number: ChiCTR2000032737. Registered 9 May 2020.

Lactate dehydrogenase, an independent risk factor of severe COVID-19 patients: a retrospective and observational study.

BACKGROUND: The World Health Organization has declared coronavirus disease 2019 (COVID-19) a public health emergency of global concern. Updated analysis of cases might help identify the risk factors of illness severity. RESULTS: The median age was 63 years, and 44.9% were severe cases. Severe patients had higher APACHE II (8.5 vs. 4.0) and SOFA (2 vs. 1) scores on admission. Among all univariable parameters, lymphocytes, CRP, and LDH were significantly independent risk factors of COVID-19 severity. LDH was positively related both with APACHE II and SOFA scores, as well as P/F ratio and CT scores. LDH (AUC = 0.878) also had a maximum specificity (96.9%), with the cutoff value of 344.5. In addition, LDH was positively correlated with CRP, AST, BNP and cTnI, while negatively correlated with lymphocytes and its subsets. CONCLUSIONS: This study showed that LDH could be identified as a powerful predictive factor for early recognition of lung injury and severe COVID-19 cases. METHODS: We extracted data regarding 107 patients with confirmed COVID-19 from Renmin Hospital of Wuhan University. The degree of severity of COVID-19 patients (severe vs. non-severe) was defined at the time of admission according to American Thoracic Society guidelines for community acquired pneumonia.

Non-optimal effectiveness of convalescent plasma transfusion and hydroxychloroquine in treating COVID-19: a case report.

BACKGROUND: Convalescent plasma (CP) transfusion was reported to be effective in treating critically ill patients with COVID-19, and hydroxychloroquine could potently inhibit SARS-CoV-2 in vitro. Herein, we reported a case receiving combination therapy with CP transfusion and hydroxychloroquine for the first time. CASE PRESENTATION: Laboratory findings showed high lactic acid level (2.1 mmol/L) and C-reactive protein (CRP, 48.8 mg/L), and low white blood cell count (1.96 × 109/L) in a 65-year-old Chinese man, who was diagnosed with severe COVID-19. CP was intravenously given twice, and hydroxychloroquine was orally administrated for a week (0.2 g, three times a day). The lactic acid and C-reactive protein levels remained high (2.1 mmol/L and 73.23 mg/L, respectively), while the arterial oxyhemoglobin saturation decreased to 86% with a low oxygenation index (OI, 76 mmHg) on day 4 after CP transfusion. His temperature returned to normal and the OI ascended above 300 on day 11. Moreover, the RNA test remained positive in throat swab, and computed tomography revealed severe pulmonary lesions on day 11 after admission. CONCLUSION: These findings suggested that the effectiveness of combination therapy with CP and hydroxychloroquine may be non-optimal, and specific therapy needs to be explored.

The effect of RAS blockers on the clinical characteristics of COVID-19 patients with hypertension.

BACKGROUND: Coronavirus disease 2019 (COVID-19), caused by a novel coronavirus (designated as SARS-CoV-2) has become a pandemic worldwide. Based on the current reports, hypertension may be associated with increased risk of sever condition in hospitalized COVID-19 patients. Angiotensin-converting enzyme 2 (ACE2) was recently identified to functional receptor of SARS-CoV-2. Previous experimental data revealed ACE2 level was increased following treatment with ACE inhibitors (ACEIs) and angiotensin receptor blockers (ARBs). Currently doctors concern whether these commonly used renin-angiotensin system (RAS) blockers-ACEIs/ARBs may increase the severity of COVID-19. METHODS: We extracted data regarding 50 hospitalized hypertension patients with laboratory confirmed COVID-19 in the Renmin Hospital of Wuhan University from Feb 7 to Mar 03, 2020. These patients were grouped into RAS blockers group (Group A, n=20) and non-RAS blockers group (Group B, n=30) according to the basic blood pressure medications. All patients continued to use pre-admission antihypertensive drugs. Clinical severity (symptoms, laboratory and chest CT findings, etc.), clinical course, and short time outcome were analyzed after hospital admission. RESULTS: Ten (50%) and seventeen (56.7%) of the Group A and Group B participants were males (P=0.643), and the average age was 52.65±13.12 and 67.77±12.84 years (P=0.000), respectively. The blood pressure of both groups was under effective control. There was no significant difference in clinical severity, clinical course and in-hospital mortality between Group A and Group B. Serum cardiac troponin I (cTnI) (P=0.03), and N-terminal (NT)-pro hormone BNP (NT-proBNP) (P=0.04) showed significant lower level in Group A than in Group B. But the patients with more than 0.04ng/mL or elevated NT-proBNP level had no statistical significance between the two groups. In patients over 65 years or under 65 years, cTnI or NT-proBNP level showed no difference between the two groups. CONCLUSIONS: We observed there was no obvious difference in clinical characteristics between RAS blockers and non-RAS blockers groups. These data suggest ACEIs/ARBs may have few effects on increasing the clinical severe conditions of COVID-19.

Arbidol monotherapy is superior to lopinavir/ritonavir in treating COVID-19.

Lopinavir/ritonavir and arbidol have been previously used to treat acute respiratory syndrome- coronavirus 2 (SARS-CoV-2) replication in clinical practice; nevertheless, their effectiveness remains controversial. In this study, we evaluated the antiviral effects and safety of lopinavir/ritonavir and arbidol in patients with the 2019-nCoV disease (COVID-19). Fifty patients with laboratory-confirmed COVID-19 were divided into two groups: including lopinavir/ritonavir group (34 cases) and arbidol group (16 cases). Lopinavir/ritonavir group received 400 mg/100mg of Lopinavir/ritonavir, twice a day for a week, while the arbidol group was given 0.2 g arbidol, three times a day. Data from these patients were retrospectively analyzed. The cycle threshold values of open reading frame 1ab and nucleocapsid genes by RT-PCR assay were monitored during antiviral therapy. None of the patients developed severe pneumonia or ARDS. There was no difference in fever duration between the two groups (P=0.61). On day 14 after the admission, no viral load was detected in arbidol group, but the viral load was found in 15(44.1%) patients treated with lopinavir/ritonavir. Patients in the arbidol group had a shorter duration of positive RNA test compared to those in the lopinavir/ritonavir group (P<0.01). Moreover, no apparent side effects were found in both groups. In conclusion, our data indicate that arbidol monotherapy may be superior to lopinavir/ritonavir in treating COVID-19.

Clinical features and dynamics of viral load in imported and non-imported patients with COVID-19.

OBJECTIVES: To compare the clinical characteristics and the dynamics of viral load between imported and non-imported patients with COVID-19. DESIGN AND METHODS: Data from 51 laboratory-confirmed patients were retrospectively analyzed. RESULTS: The incubation period in the tertiary group was longer than that in the imported and secondary groups (both p < 0.05). Fever was the most common symptom at the onset of illness (73.33%, 58.82%, and 68.42%, respectively), and half of the patients had a low-grade temperature (<38.0 °C) with a short duration of fever (<7 days). CT scans showed that most patients in the three groups had bilateral pneumonia (80.00%, 76.47%, and 73.68%, respectively). Ct values detected in the tertiary patients were similar to those for the imported and secondary groups at the time of admission (both p > 0.05). For the tertiary group, the viral load was undetectable in half of the patients (52.63%) on day 7, and in all patients on day 14. For one third of the patients in the imported and secondary groups, the viral load remained positive on day 14 after the admission. CONCLUSIONS: COVID-19 can present as pneumonia with a low onset of symptoms, and the infectivity of SARS-CoV2 may gradually decrease in tertiary patients.