Pre-existing immunity to SARS-CoV-2 associates with strong T cell responses induced by inactivated COVID-19 vaccines.

Individuals with a recent common cold coronavirus infection, which leads to pre-existing immunity against SARS-CoV-2, displayed a less severe course of COVID-19. However, the relationship between pre-existing immunity against SARS-CoV-2 and the inactivated-vaccine-induced immune response is still unknown. Here, 31 healthcare workers who received standard two doses of inactivated COVID-19 vaccines (Weeks 0 and 4, respectively) were enrolled, vaccine-induced neutralization and T cell responses were detected, and the correlation between the pre-existing SARS-CoV-2-specific immunity was analyzed. We found the SARS-CoV-2-specific antibodies, pseudovirus neutralization test (pVNT) titers, and spike-specific interferon gamma (IFN-γ) production in CD4+ and CD8+ T cells were significantly elevated after two doses of inactivated vaccines. Interestingly, the pVNT titers after the second dose of vaccination displayed no significant correlation with the pre-existing SARS-CoV-2-specific antibodies or B cells, nor the pre-existing spike-specific CD4+ T cells. Notably, the spike-specific T cell response after the second dose of vaccination was positively correlated with the pre-existing receptor binding domain (RBD)-specific B cells and CD4+ T cells, which were documented by the frequencies of RBD-binding B cells, the breadth of RBD-specific B cell epitopes, and the frequency of IFN-γ-expressing RBD-specific CD4+ T cells. Overall, the inactivated-vaccine-induced T cell responses, not the inactivated-vaccine-induced neutralization, closely correlated with pre-existing immunity to SARS-CoV-2. Our results provide a better understanding of inactivated-vaccine-induced immunity and help predict the immunogenicity induced by inactivated vaccines in individuals.

The Causal Relationship between the Morning Chronotype and the Gut Microbiota: A Bidirectional Two-Sample Mendelian Randomization Study.

BACKGROUND: Numerous observational studies have documented an association between the circadian rhythm and the composition of the gut microbiota. However, the bidirectional causal effect of the morning chronotype on the gut microbiota is unknown. METHODS: A two-sample Mendelian randomization study was performed, using the summary statistics of the morning chronotype from the European Consortium and those of the gut microbiota from the largest available genome-wide association study meta-analysis, conducted by the MiBioGen consortium. The inverse variance-weighted (IVW), weighted mode, weighted median, MR-Egger regression, and simple mode methods were used to examine the causal association between the morning chronotype and the gut microbiota. A reverse Mendelian randomization analysis was conducted on the gut microbiota, which was identified as causally linked to the morning chronotype in the initial Mendelian randomization analysis. Cochran's Q statistics were employed to assess the heterogeneity of the instrumental variables. RESULTS: Inverse variance-weighted estimates suggested that the morning chronotype had a protective effect on Family Bacteroidaceae (ß = -0.072; 95% CI: -0.143, -0.001; p = 0.047), Genus Parabacteroides (ß = -0.112; 95% CI: -0.184, -0.039; p = 0.002), and Genus Bacteroides (ß = -0.072; 95% CI: -0.143, -0.001; p = 0.047). In addition, the gut microbiota (Family Bacteroidaceae (OR = 0.925; 95% CI: 0.857, 0.999; p = 0.047), Genus Parabacteroides (OR = 0.915; 95% CI: 0.858, 0.975; p = 0.007), and Genus Bacteroides (OR = 0.925; 95% CI: 0.857, 0.999; p = 0.047)) demonstrated positive effects on the morning chronotype. No significant heterogeneity in the instrumental variables, or in horizontal pleiotropy, was found. CONCLUSION: This two-sample Mendelian randomization study found that Family Bacteroidaceae, Genus Parabacteroides, and Genus Bacteroides were causally associated with the morning chronotype. Further randomized controlled trials are needed to clarify the effects of the gut microbiota on the morning chronotype, as well as their specific protective mechanisms.

Defect reconstruction from magnetic flux leakage measurements employing modified cuckoo search algorithm.

Accurate and efficient estimation for defect profile of magnetic flux leakage (MFL) signals is important for nondestructive evaluation in industry. To improve the accuracy of defect profile reconstruction, an improved reconstruction method based on modified cuckoo search (CS), called MCS, is proposed in this paper. Firstly, a novel single-dimension updating evolution strategy is proposed to avoid the interference between multiple dimensions, which can make full use of the appropriate nest position in the historical search. Secondly, an adaptive multi-strategy difference evolution is introduced into the evolution process to improve the diversity and efficiency of CS algorithm. The proportion factor of each strategy in multi-strategy difference evolution is adjusted dynamically according to the value of the objective fitness. Finally, various MFL signals are selected to verify the effectiveness of the proposed MCS algorithm. The experiment results illustrate that the proposed method has high performance on the quality of the solution and robustness for noise.

Low-temperature plasma radiofrequency ablation in phantom limb pain: A case report.

Phantom limb pain (PLP) and phantom limb sensations are common complications postamputation. PLP is defined as persistent painful sensations perceived in the missing portion of the amputated limb. Low-temperature plasma radiofrequency ablation (coblation) technology is a relatively new technology that has shown promise in treating neuropathic pain. This report illustrates the use of coblation technology on cervical nerve roots for PLP. Coblation of the cervical nerve root was performed. Three 17G puncture trocars were placed near the C5-C6, C6-C7, and C7-T1 intervertebral foramen with computed tomography (CT) guidance. Then, a coblation needle attached to low-temperature plasma multifunctional operation system was placed near the C8 nerve root through the puncture trocars. To locate the target nerve, single stimulation (lasting for 5 s, at 1 intensity) in "cut" and "coagulation" model was given to serve as a sensory stimulation test. The stimulation induced radiating pain of the stimulated nerve away from the stimulation site to confirm our target nerve. The needle location was redirected based on the reproduction of the patient's symptoms with minimal intensity. A CT-guided cervical nerve root coblation was performed to obtain longer PLP relief. The patient reported pain relief in PLP after the operation. At 1-, 3-, and 6-month postoperative review, PLP relief was achieved. Overall activity was improved and there was necessarily need for pain medications. However, the doses of medicine significantly decreased. The analgesic effect was stable during the 6-month follow-up period. Our report demonstrates that coblation technology is successful treatment for PLP in this case. It will supply us a novel navigation in PLP treatments. Meanwhile, this finding still needs additional study for confirmation.