Predictors of immune persistence induced by two-dose BBIBP-CorV vaccine in high-risk occupational population.

BACKGROUND: The immune protection from infection may wane over time as neutralizing antibody levels decline. We aimed to develop a nomogram to predict long-term immune persistence induced by two-dose BBIBP-CorV vaccine and calculate the neutralizing antibody decline probability of individuals. METHODS: In the initial study, a total of 809 participants were recruited and randomly allocated (1:1:1) to vaccination group with three two-dose schedules on days 0 and 14, 0 and 21, or 0 and 28. The participants with neutralizing antibody titers of 16 or above on day 28 after the second dose were followed up at month 3, 6 and 10. Multivariable Cox proportional hazards regression model and nomogram model were used to identify predictors associated with maintaining of neutralizing antibody levels during 10 months after the second dose. RESULTS: A total of 744 participants followed up at day 28 after the second dose. The participants with age ≥ 50 (aHR = 3.556, 95 %CI: 1.141-4.884, P = 0.028) were associated with a high risk of response loss (titers < 16). The participants who were in 0-28 d group (aHR = 0.403, 95 %CI: 0.177-0.919, P = 0.031), had an influenza vaccination history (aHR = 0.468, 95 %CI: 0.267-0.921, P = 0.033) or were female (aHR = 0.542, 95 %CI: 0.269-0.935, P = 0.035) tended to maintain immune persistence during 10 months after the second dose. The nomogram was constructed and showed moderate discrimination[C-index:0.711 (95 %CI: 0.652-0.770); AUC: 0.731 (95 %CI: 0.663-0.792)] and good calibration. CONCLUSIONS: From 28 days to 10 months after receipt of the second dose of the BBIBP-CorV vaccine, neutralizing antibody levels were substantially decreased, especially among men, among persons 50 years of age or older, among persons with the 0-14 d group, and among persons without history of influenza vaccination. TRIAL REGISTRATION: Chinese Clinical Trial Registry, ChiCTR2100041705, ChiCTR2100041706.

Immune persistence induced by two-dose BBIBP-CorV vaccine with different intervals, and immunogenicity and safety of a homologous booster dose in high-risk occupational population.

BACKGROUND: The immune persistence of neutralizing antibodies elicited by BBIBP-CorV vaccines on day 0-14, 0-21 and 0-28 schedule, and the immunogenicity and safety of a homologous booster dose after different priming vaccination regimens is scarcely reported. METHODS: : Responders (GMT≥16) at day 28, after priming with the two-dose vaccine, were followed up at 3, 6, and 10 months. Eligible participants received a homologous booster dose at month 10 and were followed-up 28 days post-booster. RESULTS: The GMT of neutralizing antibodies in 0-28d-10 m and 0-21d-10 m group were significantly higher than 0-14d-10 m group from month 3 (71.6 & 64.2 vs 46.4, p < 0.001) to month 10 (32.4 & 28.8 vs 20.3, p < 0.001) after the second dose. On day 28 post-booster, a remarkable rebound in neutralizing antibodies (246.2, 277.5, and 288.6, respectively) was observed in the three groups. All adverse reactions were mild after booster injection. CONCLUSIONS: The priming two-dose BBIBP-CorV vaccine with 0-28 days and 0-21 days schedule could lead to a longer persistence of neutralizing antibody than the 0-14 days schedule. Regardless of the priming vaccination regimens, a homologous booster dose led to a strong rebound in neutralizing antibodies and might persist for at least 18 months.

Mass production of nitrogen and oxygen codoped carbon nanotubes by a delicately-designed Pechini method for supercapacitors and electrocatalysis.

Heteroatom-doped carbon nanotubes (CNTs) have great potential in various fields owing to their extraordinary electronic, structural, and mechanical properties. However, large-scale production of heteroatom-doped CNTs in a simple, economical, and highly efficient manner still remains challenging. Here, we report a modified Pechini method (MPM) for high-yield synthesis of N- and O-codoped CNTs (N,O-CNTs), by rapid pyrolysis of a NiCo-polymer precursor forming via a simple sol-gel process. The carbon source (i.e., citric acid) is inexpensive, and the NiCo-polymer material is the single precursor for the preparation of N,O-CNTs via a thermolysis process without the introduction of additional catalysts or carrier gas. Appropriate NiCo-organic coordination and controlled pyrolysis (i.e. heating rate, pyrolysis temperature, and holding time) are demonstrated to play vital roles in this MPM, which are critical for quick generation of small NiCo nanocatalysts with high catalytic activity and simultaneous formation of sufficient space inside the material. The growth mechanism is well studied. Benefitting from the hierarchically porous structure and the synergistic effect of N,O-codoping in the CNTs, the as-synthesized N,O-CNTs manifest excellent electrochemical performance in both supercapacitors and electrocatalysis. Density functional theory simulations show that N and O dopants could increase the densities of states of CNTs near the Fermi level and charge densities of adjacent C atoms, thus leading to improved electrochemical activity. We anticipate that this work will open up a new avenue for a high-yield and economical synthesis of heteroatom-doped CNTs for energy-related applications and beyond.

Up-regulation of nuclear factor E2-related factor 2 (Nrf2) represses the replication of SVCV.

Generation of reactive oxygen species (ROS) and failure to maintain an appropriate redox balance contribute to viral pathogenesis. Nuclear factor E2-related factor 2 (Nrf2) is an important transcription factor that plays a pivotal role in maintaining intracellular homoeostasis and coping with invasive pathogens by coordinately activating a series of cytoprotective genes. Previous studies indicated that the transcription and expression levels of Nrf2 were up-regulated in SVCV-infected EPC cells with the unknown mechanism(s). In this study, the interactions between the Nrf2-ARE signalling pathway and SVCV replication were investigated, which demonstrated that SVCV infection induced accumulation of ROS as well as protein carbonyl groups and 8-OHdG, accompanied by the up-regulation of Nrf2 and its downstream genes. At the same time, the activation of Nrf2 with D, l-sulforaphane (SFN) and CDDO-Me could repress the replication of SVCV, and knockdown of Nrf2 by siRNA could promote the replication of SVCV. Taken together, these observations indicate that the Nrf2-ARE signal pathway activates a passive defensive response upon SVCV infection. The conclusions presented here suggest that targeting the Nrf2 pathway has potential for combating SVCV infection.