Room-temperature-storable chemiluminescence freeze-drying mixes for detection of SARS-CoV-2 neutralizing antibody

As the vaccine was successfully developed, the spread of the epidemic (COVID-19) was effectively controlled. But there are still thousands of people affected COVID-19 after being vaccinated. Neutralizing activity has become a critical method for quantifying neutralizing antibody against SARS-CoV-2. However, limited to the strict conditions of cold chain transportation, the neutralizing activity test has not been widely promoted. In this study, a room-temperature-storable chemiluminescence freeze-drying mixes for SARS-CoV-2 neutralizing antibody detection was developed to decrease the cost of lyophilization step for promoting its application in third world countries. Several freeze concentrated solutions were used to protect the antigen bioactivity. The mixes can be stored at room temperature over 12 months and still exhibited great accuracy and precision. Thus, the proposed room-temperature-storable chemiluminescence freeze-drying mixes offers a cheap and stable storage method for SARS-CoV-2 neutralizing antibody detection and shows a great potential for promoting the neutralizing activity test.

The prevalence of functional gastrointestinal disorders related symptoms and the association with working place among healthcare workers who were in the fighting against COVID-19 in regional China.

Objectives: To investigate the prevalence of functional gastrointestinal disorders (FGIDs) related symptoms among healthcare workers (HWs) who were in the fighting against COVID-19 in Nanjing of China, and further to examine the association between working place and FGIDs-related symptoms among HWs during the period of COVID-19 epidemic. Methods: An online anonymous survey was conducted among those HWs without history of FGIDs, who took part in the fighting against the COVID-19 epidemic between July and September of 2021 in Nanjing, China. All the 15 FGIDs-related symptoms included in the Rome IV diagnostic questionnaire for adults were investigated in this study. The outcome variable was the presence of FGIDs-related symptoms ("Yes" or "No"), while the independent measure was participants' working place ("in-ward" or "out-ward"). Logistics regression models were applied to calculate odds ratios (ORs) and 95% confidence intervals (CIs) to assess the association of working place with FGIDs-related symptoms among those healthcare workers. Results: Totally, 336 eligible participants completed the survey. The prevalence of FGIDs-related symptoms was 48.8% (95%CI = 43.4%, 54.3%) among overall participants, with 40.7% (95%CI = 33.14%, 48.71%) and 56.3% (95%CI = 48.59%, 63.73%) for in-ward and out-ward HWs, respectively. Compared to their in-ward counterparts, those out-ward HWs were at a 1.88-fold likelihood (95%CI = 1.22, 2.89) to experience FGIDs-related symptoms during the period of fighting against the COVID-19 epidemic. After adjustment for potential confounders, such a positive association attenuated but still remained significant. Conclusions: A high prevalence of FGIDs-related symptoms was observed among those HWs who were without history of FGIDs during the fighting against COVID-19, and out-ward HWs were at a significantly higher risk to experience FGIDs-related symptoms relative to their in-ward counterparts in regional China. It has important implications that particular attention shall be paid to functional gastrointestinal issues for healthcare workers, especially those who are at uncertain risks of infectious diseases, when they participate in response to public health emergencies in future.

A longitudinal study of humoral immune responses induced by a 3-dose inactivated COVID-19 vaccine in an observational, prospective cohort.

BACKGROUND: To determine the dynamic SARS-CoV-2 specific antibody levels induced by 3 doses of an inactivated COVID-19 vaccine, CoronaVac. An observational, prospective cohort study was performed with 93 healthy healthcare workers from a tertiary hospital in Nanjing, China. Serum SARS-CoV-2 specific IgM, IgG, and neutralizing antibodies (NAb) were measured at different time points among participants who received 3 doses of inactivated COVID-19 vaccine. RESULTS: 91.3% (85/93) and 100% (72/72) participants showed positive both for SARS-CoV-2 specific IgG and NAb after 2-dose CoronaVac and after 3-dose CoronaVac, respectively. Anti-SARS-CoV-2 IgG responses reached 91.21 (55.66-152.06) AU/mL, and surrogate NAb was 47.60 (25.96-100.81) IU/mL on day 14 after the second dose. Anti-SARS-CoV-2 IgG responses reached 218.29 (167.53-292.16) AU/mL and surrogate NAb was 445.54 (171.54-810.90) IU/mL on day 14 after the third dose. Additionally, SARS-CoV-2 specific surrogate neutralizing antibody titers were highly correlated with serum neutralization activities against Ancestral, Omicron, and Delta strains. Moreover, significantly higher SARS-CoV-2 IgG responses, but not NAb responses, were found in individuals with breakthrough infection when compared to that of 3-dose CoronaVac recipients. CONCLUSIONS: CoronaVac elicited robust SARS-CoV-2 specific humoral responses. Surrogate NAb assay might substitute for pseudovirus neutralization assay. Monitoring SARS-CoV-2 antibody responses induced by vaccination would provide important guidance for the optimization of COVID-19 vaccines.

The Third dose of CoronVac vaccination induces broad and potent adaptive immune responses that recognize SARS-CoV-2 Delta and Omicron variants.

The waning humoral immunity and emerging contagious severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants resulted in the necessity of the booster vaccination of coronavirus disease 2019 (COVID-19). The inactivated vaccine, CoronaVac, is the most widely supplied COVID-19 vaccine globally. Whether the CoronaVac booster elicited adaptive responses that cross-recognize SARS-CoV-2 variants of concern (VoCs) among 77 healthy subjects receiving the third dose of CoronaVac were explored. After the boost, remarkable elevated spike-specific IgG and IgA responses, as well as boosted neutralization activities, were observed, despite 3.0-fold and 5.9-fold reduced neutralization activities against Delta and Omicron strains compared to that of the ancestral strain. Furthermore, the booster dose induced potent B cells and memory B cells that cross-bound receptor-binding domain (RBD) proteins derived from VoCs, while Delta and Omicron RBD-specific memory B cell recognitions were reduced by 2.7-fold and 4.2-fold compared to that of ancestral strain, respectively. Consistently, spike-specific circulating follicular helper T cells (cTfh) significantly increased and remained stable after the boost, with a predominant expansion towards cTfh17 subpopulations. Moreover, SARS-CoV-2-specific CD4+ and CD8+ T cells peaked and sustained after the booster. Notably, CD4+ and CD8+ T cell recognition of VoC spike was largely preserved compared to the ancestral strain. Individuals without generating Delta or Omicron neutralization activities had comparable levels of CD4+ and CD8+ T cells responses as those with detectable neutralizing activities. Our study demonstrated that the CoronaVac booster induced broad and potent adaptive immune responses that could be effective in controlling SARS-CoV-2 Delta and Omicron variants.

Effect of liver injury on prognosis and treatment of hospitalized patients with COVID-19 pneumonia.

BACKGROUND: Liver injury is common in patients with coronavirus disease 2019 (COVID-19), although its effect on patient outcomes has not been well studied. This study aimed to evaluate the effect of liver injury on the prognosis and treatment of patients with COVID-19 pneumonia. METHODS: In this retrospective, single-center study, data on 109 hospitalized patients with COVID-19 pneumonia were extracted and analyzed. The primary composite end-point event was the use of mechanical ventilation or death. RESULTS: At admission, of the 109 patients enrolled, 56 patients (51.4%) were diagnosed with severe disease, and 39 (35.8%) presented with liver injury, which mainly manifested as elevated levels of alanine aminotransferase (ALT) or aspartate aminotransferase (AST) accompanied simultaneously by an increase in the level of γ-glutamyl transferase. A primary composite end-point event occurred in 21 patients (19.3%). Liver injury was more prevalent in patients with severe disease than in those with non-severe disease (46.4% vs. 24.5%, P=0.017). However, there was no significant difference found between severe and non-severe patients in the use of mechanical ventilation, mortality, hospital stay, or use and dosage of glucocorticoids between individuals with and without liver injury (all P>0.05). The degree of disease severity (OR =7.833, 95% CI, 1.834-31.212, P=0.005) and presence of any coexisting illness (OR =4.736, 95% CI, 1.305-17.186, P=0.018) were predictable risk factors for primary composite end-point events, whereas liver injury had no significance in this aspect (OR =0.549, 95% CI, 0.477-5.156, P=0.459). CONCLUSIONS: Liver injury was more common in severe cases of COVID-19 pneumonia than in non-severe cases. However, liver injury had no negative effect on the prognosis and treatment of COVID-19 pneumonia.

Resumption of Endodontic Practices in COVID-19 Hardest-Hit Area of China: A Web-based Survey.

INTRODUCTION: The purpose of this study was to investigate the resumption of endodontic practices in Hubei Province, China 1 month after the end of the lockdown. METHODS: A Web-based survey was sent to 1069 active endodontic specialists and general dentists who provided endodontic care in Hubei Province from May 7 to May 9, 2020. The survey consisted of 18 questions on demographics, the current situation of endodontic practice for the participants, and concerns regarding contracting or spreading the virus in newly opened endodontic practices. RESULTS: A total of 322 participants completed the survey. Most respondents (62%) were from Wuhan. Almost 83% of the respondents have resumed their endodontic practice partially or fully. Most respondents in practice (99%) would take measures to screen patients before treatment including paid screening measures. More than 93% of the respondents reported having taken special measures for routine endodontic treatment at this stage, with the most common measure taken being wearing an N95 mask. The rubber dam was recognized as efficient in preventing infection by most respondents. Many respondents were concerned about contracting coronavirus disease 2019 (COVID-19) as a result of routine endodontic practice at this stage, and respondents with more than 11 years of endodontic experience were significantly less concerned about infection compared with those with fewer than 5 years of experience (P < .05). CONCLUSIONS: There is a fear of contracting/spreading COVID-19 among endodontic clinicians, the fear is negatively associated with years of practice, and most clinicians believe that rubber dam isolation can protect them and their patients from COVID-19.

The value of high-flow nasal cannula oxygen therapy in treating novel coronavirus pneumonia.

OBJECTIVE: This study aimed to investigate the value of high-flow nasal cannula (HNFC) oxygen therapy in treating patients with severe novel coronavirus pneumonia (COVID-19). METHODS: The clinical data of 22 patients with severe COVID-19 were collected. The heart rate (HR), respiratory rate (RR) and oxygenation index (PO2 /FiO2 ) at 0, 6, 24 and 72 hours after treatment were compared between the HFNC oxygen therapy group and the conventional oxygen therapy (COT) group. In addition, the white blood cell (WBC) count, lymphocyte (L) count, C-reactive protein (CRP) and procalcitonin (PCT) were compared before and at 72 hours after oxygen therapy treatment. RESULTS: The differences at 0 hours between the two groups were not statistically significant. Compared with COT group,in the HFNC oxygen therapy group, HR, RR and PaO2 /FiO2 were better at 6 hours after treatment, PaO2 /FiO2 was better at 24 and 72 hours. After 72 hours, L and CRP had improved in the HFNC oxygen therapy group compared with the COT group, but the differences in WBC and PCT were not statistically significant. The length of stay in the intensive care unit (ICU) and the total length of hospitalization was shorter in the HFNC oxygen therapy group than in the COT group. CONCLUSION: Compared with COT, early application of HFNC oxygen therapy in patients with severe COVID-19 can improve oxygenation and RR, and HFNC oxygen therapy can improve the infection indexes of patients and reduce the length of stay in the ICU of patients. Therefore, it has high clinical application value.

Characteristics of Endodontic Emergencies during Coronavirus Disease 2019 Outbreak in Wuhan.

INTRODUCTION: In late 2019, an outbreak of a new coronavirus named severe acute respiratory syndrome coronavirus 2 was detected in Wuhan, China. A great percentage of patients with this disease developed symptoms of dry cough, malaise, and a high fever. During this time, several patients requiring assessment and treatment of endodontic emergencies were directed to the School and Hospital of Stomatology at Wuhan University, Wuhan, China. We examined the characteristics of these patients. METHODS: A total of 96 patients with a mean age of 42.24 ± 18.32 years visited the general and emergency department of the School and Hospital of Stomatology at Wuhan University because of endodontic emergencies during the peak period of February 22 to March 2, 2020. Patient information was collected and organized by date of visit, sex, age, and systemic disease history. Body temperature was measured and acquired for each patient, a coronavirus disease 2019 (COVID-19) epidemiologic investigation questionnaire was given to each patient, an endodontic diagnosis was determined for the offending tooth, and a verbal numerical rating scale (VNRS) was used to record pain levels. RESULTS: Of the total patient visits during this period, 50.26% of visits were for endodontic treatment. No patients had a fever (>37.2°C). One patient with a confirmed COVID-19 history was admitted after recovery. Three admitted patients had been exposed to confirmed or suspected COVID-19 patients. Twelve admitted patients (12.5%) with a mean age of 62.42 ± 13.77 years had a history of systemic diseases. The most common age group for endodontic emergencies was 45-64 years (30.21%), and patients of this group showed a significantly higher mean VNRS score compared with that of the 6- to 19-year age group and the 20- to 34-year age group (P < .05). The majority of endodontic emergency diagnoses were diseases of symptomatic irreversible pulpitis (53.10%). Patients who were diagnosed with symptomatic irreversible pulpitis, symptomatic apical periodontitis, and acute apical abscess showed a significantly higher mean VNRS score than that of other groups (P < .05). CONCLUSIONS: Endodontic emergencies, with symptomatic irreversible pulpitis being the most common, consist of a much higher proportion of dental emergencies in a COVID-19 high-risk area than normally. Vital pulp therapy can advantageously reduce treatment time, resulting in a reduced risk of infection for vital pulp cases. Rubber dams, personal protective equipment, and patient screening are of great importance during the COVID-19 outbreak in protecting clinicians.