Understanding influencing attributes of COVID-19 vaccine preference and willingness-to-pay among Chinese and American middle-aged and elderly adults: A discrete choice experiment and propensity score matching study

Background and objective

COVID-19 has imposed burdens on public health systems globally. Owing to the urgency of vaccination, this study aimed at comparing the differences in preference and willingness to pay of COVID-19 vaccine among Chinese and American middle-aged and elderly adults.

Methods

A cross-sectional survey containing demographic questions, rating their acceptance of COVID-19 vaccination with and without recommendations from friends, family members or employers (the social cues referred to in our study), and a discrete choice experiment understanding COVID-19 vaccine preference and willingness to pay was conducted to collect data. Propensity score matching was utilized to adjust confounding factors of baseline characteristics and the relative importance of respondents' preference for each attribute and its level was estimated using a conditional logit model. Then, willingness to pay was calculated.

Results

In total, 3,494 (2,311 and 1,183 from China and the United States, respectively) completed the questionnaire, among which 3,444 questionnaires were effective. After propensity score matching, 1,604 respondents with 802 from the US and 802 from China were included. Under the influence of the social cues, Chinese respondents' vaccine acceptance decreased from 71.70 to 70.70%, while American respondents' vaccine acceptance increased from 74.69 to 75.81%. The discrete choice experiment showed that American respondents regarded the efficacy of COVID-19 vaccine as the most important attribute, whereas Chinese respondents attached the highest importance to the cost of vaccination. But overall, the COVID-19 vaccine with the higher efficacy, the milder adverse effect, the lower cost, and the longer duration will promote the preference of the public in both countries. Additionally, the public were willing to spend the most money for a reduction in COVID-19 vaccine adverse effect from moderate to very mild (37.476USD for the United States, 140.503USD for China), followed by paying for the 1% improvement in its efficacy and paying for the one-month extension of its duration.

Conclusion

Given the impact of social cues on vaccine acceptance, Chinese government should promote reasonable vaccine-related information to improve national vaccination acceptance. Meanwhile, considering the influence of COVID-19 attributes on public preference and willingness to pay, regulating the vaccine pricing, improving the efficacy of the vaccine, reducing its adverse effect, and prolonging the duration of the vaccine works will contribute to vaccine uptake.

[Fibroblasts overpressing WNT2b cause impairment of intestinal mucosal barrier]

OBJECTIVE

To investigate the mechanism by which fibroblasts with high WNT2b expression causes intestinal mucosa barrier disruption and promote the progression of inflammatory bowel disease (IBD).

METHODS

Caco-2 cells were treated with 20% fibroblast conditioned medium or co-cultured with fibroblasts highly expressing WNT2b, with the cells without treatment with the conditioned medium and cells co-cultured with wild-type fibroblasts as the control groups. The changes in barrier permeability of Caco-2 cells were assessed by measuring transmembrane resistance and Lucifer Yellow permeability. In Caco-2 cells co-cultured with WNT2b-overexpressing or control intestinal fibroblasts, nuclear entry of β-catenin was detected with immunofluorescence assay, and the expressions of tight junction proteins ZO-1 and E-cadherin were detected with Western blotting. In a C57 mouse model of dextran sulfate sodium (DSS)-induced IBD-like enteritis, the therapeutic effect of intraperitoneal injection of salinomycin (5 mg/kg, an inhibitor of WNT/β-catenin signaling pathway) was evaluated by observing the changes in intestinal inflammation and detecting the expressions of tight junction proteins.

RESULTS

In the coculture system, WNT2b overexpression in the fibroblasts significantly promoted nuclear entry of β-catenin (P < 0.01) and decreased the expressions of tight junction proteins in Caco-2 cells; knockdown of FZD4 expression in Caco-2 cells obviously reversed this effect. In DSS-treated mice, salinomycin treatment significantly reduced intestinal inflammation and increased the expressions of tight junction proteins in the intestinal mucosa.

CONCLUSION

Intestinal fibroblasts overexpressing WNT2b causes impairment of intestinal mucosal barrier function and can be a potential target for treatment of IBD.

Uniaxial cyclic stretch enhances osteogenic differentiation of OPLL-derived primary cells via YAP-Wnt/β-catenin axis

The pathogenesis of posterior longitudinal ligament ossification (OPLL) remains inadequately understood. Mechanical stimulation is one of the important pathogenic factors in OPLL. As one of the mechanical stimulation transduction signals, the yes-associated protein (YAP) interacts with the Wnt/β-catenin signalling pathway, which plays an important role in osteogenic differentiation. This study aimed to demonstrate the role of YAP-Wnt/β-catenin axis in cell differentiation induced by mechanical stress. Primary cells extracted from posterior longitudinal ligament tissues from OPLL or non-OPLL patients were subjected to sinusoidal uniaxial cyclic stretch (5 %, 0.5 Hz, 3 d). The expression of runt-related transcription factor 2, collagen I, osterix, osteocalcin and alkaline phosphatase were compared between the static and the experimental groups. In addition, the cytoskeleton was detected using phalloidin staining while YAP phosphorylation states and nuclear location were identified using immunofluorescence. The results showed that mechanical stretching loading increased the expression of osteogenic genes and proteins in the OPLL group, while it had no significant effect on the control group. When OPLL cells were stretched, YAP exhibited an obvious nuclear translocation and the Wnt/β-catenin pathway was activated. Knocking down YAP or β-catenin could weaken the impact upon osteogenic differentiation induced by mechanical stimulation. YAP-mediated mechanical stimulation promoted osteogenic differentiation of OPLL cells through Wnt/β-catenin pathway and this progress was independent of the Hippo pathway.

The J-shape Association between Total Bilirubin and Stroke in Older Patients with Obstructive Sleep Apnea Syndrome: A Multicenter Study

OBJECTIVES

To explore the relationship between total bilirubin (TBil) and stroke risk in older patients with obstructive sleep apnea syndrome (OSAS).

METHODS

A total of 1,007 patients with OSAS without stroke history aged ≥ 60 years and with complete serum TBil records were enrolled in this study. The median follow-up was 42 months. Participants were divided into four groups based on the quartile of the baseline serum TBil concentration. Multivariate Cox proportional hazards analysis and restricted cubic spline (RCS) were used to investigate the association of TBil with the incidence of new-onset stroke.

RESULTS

The PRIMARY part: the third quantile TBil level group had the lowest prevalence of stroke among the four groups. The RCS functions depicted a J-type curve relationship between TBil (3.3-33.3 µmol/L) and stroke (nonlinear P < 0.05). When the TBil level was in the range of 3.3 to 11.5 µmol/L, the possible protective influence of bilirubin against stroke in patients with OSAS enhanced with an increasing TBil level. However, when the TBil level exceeded 11.5 µmol/L and gradually increased, the effect of TBil on stroke risk became more and more pronounced. The SECONDARY part: for every 1 µmol/L increase in TBil levels in the range of 11.5 to 33.3 µmol/L, the risk of stroke in patients with OSAS increased by 16.2% (P < 0.001). In addition, there was a higher risk in women with OSAS (hazard ratio (HR)=1.292, 95% confidence interval (95%CI): 1.093-1.528; P = 0.003). Moreover, an increased TBil level alone was significantly associated with stroke in subjects aged < 75 years (HR: 1.190, 95%CI: 1.069-1.324), patients with mild-to-moderate OSAS (HR: 1.215, 95%CI: 1.083-1.364), and individuals without atrial fibrillation (AF) (HR: 1.179, 95%CI: 1.083-1.285) within a TBil level in the range of 11.5 to 33.3 µmol/L.

CONCLUSIONS

Both lower and higher bilirubin levels may increase the risk of stroke in older persons with OSAS, and there was a J-type dose-response relationship. The risk of stroke was lowest when the TBil level was approximately 11.5 µmol/L.

Portable diagnostic package for Thomson scattering and optical emission spectroscopy on Princeton field-reversed configuration 2 (PFRC 2)

An Advanced Research Projects Agency-Energy funded diagnostic system has been deployed to the Princeton field-reversed configuration 2 (PFRC-2) device, located at Princeton Plasma Physics Laboratory. The Portable Diagnostic Package (PDP), designed at Oak Ridge National Laboratory, allows for the measurement of Thomson Scattering (TS) for electron density and temperature and Optical Emission Spectroscopy (OES) for ion temperature, impurity density, and ion velocity. A tunable spectrometer on the PDP with three gratings provides the flexibility to measure low (1 eV) and high (1000 eV) electron temperature ranges from TS. Additionally, using a second spectrometer, the OES diagnostic can survey light emission from various ion excitation levels for wide wavelength ranges. The electron density (<2 × 10¹⁹ m^-3) of plasmas generated in PFRC-2 has been below the PDP TS discrimination threshold, which has made TS signal detection challenging against a high-background of laser stray light. The laser stray light was iteratively reduced by making modifications to the entrance and exit geometry on PFRC-2. Rayleigh scattering experiments on PFRC have yielded the TS discrimination sensitivity to be >1 × 10²⁰ m^-3 for the PDP. A recently implemented narrow-band notch spectral filter that masks the second harmonic 532 nm Nd:YAG laser wavelength has increased the system's TS light discrimination sensitivity 65 times compared to the instance when the notch filter was not implemented. The hardware implementation including design changes to the flight tubes and Brewster windows will be discussed, along with results from Rayleigh and rotational Raman scattering sensitivity analyses, which were used to establish a quantitative figure of merit on the system performance. The Raman scattering calibration with the notch filter has improved the PDP electron density threshold to 1 ± 0.5 × 10¹⁸ m^-3.

Implementation of a portable diagnostic system for Thomson scattering measurements on an electrothermal arc source

To fulfill the increasing needs of diagnostic support for researchers in plasma technology, a portable diagnostic package (PDP) equipped for both laser Thomson scattering (TS) and optical emission spectroscopy has been designed and constructed at Oak Ridge National Laboratory (ORNL), aiming to measure the temperature and number density of electrons and temperatures of ions in plasma devices. The PDP has been initially implemented on a high density and low temperature electrothermal arc source (ET-arc) at ORNL to test its TS capability. TS from the plasmas in the ET-arc has been obtained using the PDP. The electron temperature and number density were determined from TS spectra. These results were then compared to measurements from previous studies on the ET-arc. The TS diagnostic measured 0.8 ± 0.1, 1.3 ± 0.2, and 0.7 ± 0.1 eV and (4.4 ± 0.5) × 10²¹, (5.9 ± 0.7) × 10²¹, and (4.3 ± 0.5) x 10²¹ m^-3, respectively, from three lines of sight that transect the plasma column.

P11.75.B Survival benefit of radiotherapy and surgery in patients with lung cancer brain metastases with poor prognosis factors

Background

Radiotherapy and surgery are the standard treatments for lung cancer brain metastases (BMs). However, limitted studies focused on the treatments for patients with lung cancer BMs with poor prognosis factors. The purpose of this study was to investigate the effects of radiotherapy and surgery in patients with lung cancer BMs with poor prognosis factors, providing reference for clinical strategies.

Material and Methods

We analyzed retrospectively 714 patients with lung cancer BMs. A 1:1 propensity score matching (PSM) was performed to balance potential confounders. Analyses of overall survival (OS) and risk factors for OS were assessed by log-rank test and Cox proportional hazard model.

Results

Age ≥65 years, Karnofsky Performance Scale (KPS) score ≤70, anaplastic large-cell lymphoma kinase (ALK)/epidermal growth factor receptor (EGFR) wild type, extracranial metastases, non-surgery and non-radiotherapy led to poor prognosis. Patients were stratified according to these factors. Radiotherapy and surgery showed no survival benefit in patients with aged ≥65 years or pretreatment KPS score ≤70 before and after PSM. Before PSM, whole brain radiotherapy (WBRT) improved the OS and predicted good prognosis in patients with ALK/EGFR wild type or extracranial metastases. WBRT also predicted good prognosis in patients with non-surgery. Stereotactic radiosurgery (SRS) improved the OS and predicted good prognosis in patients with ALK/EGFR wild type or non-surgery. WBRT plus SRS improved the OS and predicted good prognosis in patients with extracranial metastases or non-surgery. WBRT plus SRS also predicted good prognosis in patients with ALK/EGFR wild type. Surgery improved the OS and predicted good prognosis in patients with non-radiotherapy. After PSM, SRS improved the OS and predicted good prognosis in patients with non-surgery. WBRT plus SRS improved the OS and predicted good prognosis in patients with non-surgery or extracranial metastases. WBRT plus SRS also predicted good prognosis in patients with ALK/EGFR wild type. Surgery improved the OS of patients with non-radiotherapy. We defined that the treatment would provide significant survival benefit if it both prolonged the OS and predicted good prognosis. Meanwhile, the results after PSM were more convincing than the results before PSM.

Conclusion

Radiotherapy has significant survival benefit in patients with lung cancer BMs with poor prognosis factors, including patients with ALK/EGFR wild type or extracranial metastases or non-surgery. Surgery only has significant survival benefit in patients with non-radiotherapy.

The Preferences for Attributes of Initial COVID-19 Diagnosis in the US and China during the Pandemic: A Discrete Choice Experiment with Propensity Score Matching

Background

China and the United States play critical leading roles in the global effort to contain the COVID-19 virus. Therefore, their population’s preferences for initial diagnosis were compared to provide policy and clinical insights.

Objective

We aim to quantify and compare the public’s preferences for medical management of fever and the attributes of initial diagnosis in the case of presenting symptoms during the COVID-19 pandemic in China and the United States.

Methods

We conducted a cross-sectional study from January to March 2021 in China and the United States using an online discrete choice experiment (DCE) questionnaire distributed through Amazon Mechanical Turk (MTurk; in the United States) and recruited volunteers (in China). Propensity score matching (PSM) was used to match the 2 groups of respondents from China and the United States to minimize confounding effects. In addition, the respondents’ preferences for different diagnosis options were evaluated using a mixed logit model (MXL) and latent class models (LCMs). Moreover, demographic data were collected and compared using the chi-square test, Fisher test, and Mann-Whitney U test.

Results

A total of 9112 respondents (5411, 59.4%, from China and 3701, 40.6%, from the United States) who completed our survey were included in our analysis. After PSM, 1240 (22.9%) respondents from China and 1240 (33.5%) from the United States were matched for sex, age, educational level, occupation, and annual salary levels. The segmented sizes of 3 classes of respondents from China were 870 (70.2%), 270 (21.8%), and 100 (8.0%), respectively. Meanwhile, the US respondents’ segmented sizes were 269 (21.7%), 139 (11.2%), and 832 (67.1%), respectively. Respondents from China attached the greatest importance to the type of medical institution (weighted importance=40.0%), while those from the United States valued the waiting time (weighted importance=31.5%) the most. Respondents from China preferred the emergency department (coefficient=0.973, reference level: online consultation) and fever clinic (a special clinic for the treatment of fever patients for the prevention and control of acute infectious diseases in China; coefficient=0.974, reference level: online consultation), while those from the United States preferred private clinics (general practices; coefficient=0.543, reference level: online consultation). Additionally, shorter waiting times, COVID-19 nucleic acid testing arrangements, higher reimbursement rates, and lower costs were always preferred.

Conclusions

Improvements in the availability of COVID-19 testing and medical professional skills and increased designated health care facilities may help boost potential health care seeking during COVID-19 and prevent unrecognized community spreading of SARS-CoV-2 in China and the United States. Moreover, to better prevent future waves of pandemics, identify undiagnosed patients, and encourage those undiagnosed to seek health care services to curb the pandemic, the hierarchical diagnosis and treatment system needs improvement in China, and the United States should focus on reducing diagnosis costs and raising the reimbursement rate of medical insurance.

Selective effects of perinatal estrogen on proliferation and new neurons in hippocampus and piriform cortex of rats at weaning

BACKGROUND

A recent report links heightened prenatal amniotic estrogen levels to an increased risk of autism spectrum disorder (ASD). In this study, we examined the developmental effects of perinatal estrogen treatment on stem cell activity in weaned rats.

METHODS

Sprague-Dawley rats received ethinyl estradiol (EE2, 10µg/kg/day) or vehicle orally from gestational day 6 until parturition. Offspring were then treated with the same daily dose from postnatal days (PNDs) 1-21. The effects of perinatal estrogen treatment on stem cell activities in the subgranular zone (SGZ) of the hippocampus and the piriform cortex were evaluated in male and female rat pups.

RESULTS

EE₂ treatment increased the total Ki67-immunoreactive (Ki67-ir) cell counts in the SGZ of males and females (p<0.05). However, no treatment or sex differences were detectable in the density of the doublecortin (DCX)-immunoreactive (DCX-ir) deposits in the hippocampus. In the piriform cortex, no treatment or sex differences were detected in Ki67-ir cell counts. However, the EE₂ treatment significantly reduced the DCX-ir cell count in male, but not female rats (male EE₂ group=29₂±22/mm², male vehicle group=402±19/mm², female EE² group=34₂±15/mm², female vehicle group=331±9/mm²).

CONCLUSIONS

Perinatal estrogen treatment increased hippocampal Ki67-ir cell counts in both sexes and selectively reduced DCX-ir cell counts in the piriform cortex of males. These data suggest that exposure to abnormally high levels of estrogens early in life may have an impact on neural cell development. Alterations in development so early in life may have long-term cognitive impact.

[The efficacy and prognostic factors of immunotherapy in advanced non-small cell lung cancer patients with different driver gene mutations]

Objective: To explore the efficacy and prognostic factors of immunotherapy in advanced non-small cell lung cancer (NSCLC) patients with different driver gene mutations. Methods: Medical records of advanced NSCLC patients who harbored driver gene mutations (EGFR, KRAS, ALK and etc.) and received PD-1 inhibitors in Henan Cancer Hospital from April 2016 to May 2021 were collected. Treatment patterns, progression free survival (PFS), overall survival (OS) and prognostic factors of patients with driver gene mutations were estimated. Results: A total of 120 patients were included. There were 70 males and 50 females, with a median age [M(Q₁,Q₃)] of 57 (50, 65) years. Of these, 52 patients harbored KRAS mutations, 42 patients harbored EGFR mutations, 16 patients harbored ERBB2 mutations, 5 patients harbored MET mutations or amplifications, 5 patients harbored ROS-1 mutations, 2 patients harbored BRAF mutations, and the last 2 patients harbored ALK and RET mutations, respectively. The PFS and OS [M (95%CI)] were 6.4 (5.1-7.8) and 31.2 (22.0-40.3) months in 120 participated patients. Patients with KRAS mutations showed the greatest survival benefit from Immune checkpoint inhibitors (ICIs) with the PFS of 9.7 (4.8-14.6) months and OS of 31.2 (19.4-50.6) months. They mostly received the first-line (34.6%, 18/52) and second-line (38.5%, 20/52) ICIs. The PFS and OS of EGFR mutant patients were 3.9 (1.8-6.1) months and 18.0 (12.1-23.8) months, respectively. They tended to receive ICIs after resistance to EGFR-tyrosine kinase inhibitors (TKIs), and the proportion of second-, third-, fourth or further-line drugs was 38.1% (16/42), 11.9% (5/42), and 47.6% (20/42), respectively. PD-L1 expression level (negative vs ≥50% positive: HR=3.710, 95%CI: 1.372-10.031, P=0.010; 1%-49% positive vs ≥50% positive: HR=2.738, 95%CI: 0.841-8.912, P=0.094), age (every additional year: HR=0.957, 95%CI: 0.933-0.982, P=0.001) and different driver mutations status (EGFR vs KRAS: HR=2.676, 95%CI: 1.317-5.436, P=0.006; ERBB2 vs KRAS: HR=3.411, 95%CI: 1.493-7.792, P=0.004; other mutations vs KRAS: HR=0.727, 95%CI: 0.322-1.643, P=0.444) were prognostic factors for PFS. While PD-L1 expression level (negative vs ≥50% positive: HR=2.305, 95%CI: 0.748-7.103, P=0.146; 1%-49% positive vs ≥50% positive: HR=1.286, 95%CI: 0.337-4.913, P=0.713), and treatment lines of ICIs (first-line vs ≥ third-line: HR=0.322, 95%CI: 0.114-0.914, P=0.033; second-line vs ≥ third-line: HR=0.375, 95%CI: 0.178-0.789, P=0.010) were prognostic factors for OS. Conclusions: KRAS mutant NSCLC patients mostly receive ICIs at the front line, and have best survival benefits from immunotherapy. While EGFR mutant NSCLC patients tend to receive ICIs at the back line, and obtain reasonable survival benefits. PD-L1 expression level, age, and different driver mutations status are prognostic factors for PFS, and PD-L1 expression level and treatment lines of ICIs are prognostic factors for OS.

The Construct Structures of Psychological and Behavioral Responses to COVID-19 Pandemic in Pregnant Women

AIM

The present study aimed to investigate the construct structure behind the psychosocial response, behavioral response, prenatal depression, and post-traumatic stress disorder (PTSD) in pregnant women during the COVID-19 pandemic in China.

METHOD

The validated Chinese version of the Edinburgh Postnatal Depression Scale (EPDS), PTSD CheckList (PCL)-6, and two newly established scales for COVID-19-related psychological and behavioral responses were used. Structural equation modeling (SEM) analysis was applied to evaluate the structural relationships of psychological and behavioral responses during the COVID-19 pandemic.

RESULTS

Of the 1,908 mothers who completed the questionnaires, 1,099 met the criteria for perinatal depression, and 287 were positively screened for PTSD, where 264 women exceed the cut-off points for both. Pregnant women with full-time or part-time jobs tended to have the lowest scores of EPDS (10.07 ± 5.11, P < 0.001) and stress levels (23.85 ± 7.96, P = 0.004), yet they were more likely to change their behavior in accordance with the COVID-19 outbreak (13.35 ± 3.42, P = 0.025). The structural model fit the data (χ² = 43.260, p < 0.001) and resulted in satisfactory fit indices (CFI = 0.984, TLI = 0.959, RMSEA = 0.072, and χ²/df = 10.815), all path loadings were significant (p < 0.05). The SEM indicates that the level of QoL was attributable to the occurrence of PND, leading to PTSD, and COVID-19 related behavioral and psychological responses.

CONCLUSION

The inter-relationships between the COVID-19-related psychosocial and behavioral responses have been assessed, indicating that the pandemic increased the burden of perinatal depression. Psychoeducation, as well as other psychological interventions, may be needed to alleviate the COVID-19-based anxiety and increase their engagement in protective behaviors.