Safety and immunogenicity of a protein subunit COVID-19 vaccine (ZF2001) in healthy children and adolescents aged 3-17 years in China: a randomised, double-blind, placebo-controlled, phase 1 trial and an open-label, non-randomised, non-inferiority, phase 2 trial.

BACKGROUND: ZF2001 is a recombinant protein subunit vaccine against SARS-CoV-2 that has been approved for use in China, Colombia, Indonesia, and Uzbekistan in adults aged 18 years or older, but not yet in children and adolescents younger than 18 years. We aimed to evaluate the safety and immunogenicity of ZF2001 in children and adolescents aged 3-17 years in China. METHODS: The randomised, double-blind, placebo-controlled, phase 1 trial and the open-label, non-randomised, non-inferiority, phase 2 trial were done at the Xiangtan Center for Disease Control and Prevention (Hunan Province, China). Healthy children and adolescents aged 3-17 years, without a history of SARS-CoV-2 vaccination, without a history of COVID-19, without COVID-19 at the time of the study, and without contact with patients with confirmed or suspected COVID-19 were included in the phase 1 and phase 2 trials. In the phase 1 trial, participants were divided into three groups according to age (3-5 years, 6-11 years, and 12-17 years). Each group was randomly assigned (4:1), using block randomisation with five blocks, each with a block size of five, to receive three 25 µg doses of the vaccine, ZF2001, or placebo intramuscularly in the arm 30 days apart. The participants and investigators were masked to treatment allocation. In the phase 2 trial, participants received three 25 µg doses of ZF2001 30 days apart and remained stratified by age group. For phase 1, the primary endpoint was safety and the secondary endpoint was immunogenicity (humoral immune response on day 30 after the third vaccine dose: geometric mean titre [GMT] of prototype SARS-CoV-2 neutralising antibodies and seroconversion rate, and geometric mean concentration [GMC] of prototype SARS-CoV-2 receptor-binding domain [RBD]-binding IgG antibodies and seroconversion rate). For phase 2, the primary endpoint was the GMT of SARS-CoV-2 neutralising antibodies with seroconversion rate on day 14 after the third vaccine dose, and the secondary endpoints included the GMT of RBD-binding antibodies and seroconversion rate on day 14 after the third vaccine dose, the GMT of neutralising antibodies against the omicron BA.2 subvariant and seroconversion rate on day 14 after the third vaccine dose, and safety. Safety was analysed in participants who received at least one dose of the vaccine or placebo. Immunogenicity was analysed in the full-analysis set (ie, participants who received at least one dose and had antibody results) by intention to treat and in the per-protocol set (ie, participants who completed the whole vaccination course and had antibody results). Non-inferiority in the phase 2 trial (neutralising antibody titre of participants from this trial aged 3-17 years vs that of participants aged 18-59 years from a separate phase 3 trial) for clinical outcome assessment was based on the geometric mean ratio (GMR) and was considered met if the lower bound of the 95% CI for the GMR was 0·67 or greater. These trials are registered with ClinicalTrials.gov, NCT04961359 (phase 1) and NCT05109598 (phase 2). FINDINGS: Between July 10 and Sept 4, 2021, 75 children and adolescents were randomly assigned to receive ZF2001 (n=60) or placebo (n=15) in the phase 1 trial and were included in safety and immunogenicity analyses. Between Nov 5, 2021, and Feb 14, 2022, 400 participants (130 aged 3-7 years, 210 aged 6-11 years, and 60 aged 12-17 years) were included in the phase 2 trial and were included in the safety analysis; six participants were excluded from the immunogenicity analyses. 25 (42%) of 60 participants in the ZF2001 group and seven (47%) of 15 participants in the placebo group in phase 1, and 179 (45%) of 400 participants in phase 2, had adverse events within 30 days after the third vaccination, without a significant difference between groups in phase 1. Most adverse events were grade 1 or 2 (73 [97%] of 75 in the phase 1 trial, and 391 [98%] of 400 in the phase 2 trial). One participant in the phase 1 trial and three in the phase 2 trial who received ZF2001 had serious adverse events. One serious adverse event (acute allergic dermatitis) in the phase 2 trial was possibly related to the vaccine. In the phase 1 trial, on day 30 after the third dose, in the ZF2001 group, seroconversion of neutralising antibodies against SARS-CoV-2 was observed in 56 (93%; 95% CI 84-98) of 60 participants, with a GMT of 176·5 (95% CI 118·6-262·8), and seroconversion of RBD-binding antibodies was observed in all 60 (100%; 95% CI 94-100) participants, with a GMC of 47·7 IU/mL (95% CI 40·1-56·6). In the phase 2 trial, on day 14 after the third dose, seroconversion of neutralising antibodies against SARS-CoV-2 was seen in 392 (99%; 95% CI 98-100) participants, with a GMT of 245·4 (95% CI 220·0-273·7), and seroconversion of RBD-binding antibodies was observed in all 394 (100%; 99-100) participants, with a GMT of 8021 (7366-8734). On day 14 after the third dose, seroconversion of neutralising antibodies against the omicron subvariant BA.2 was observed in 375 (95%; 95% CI 93-97) of 394 participants, with a GMT of 42·9 (95% CI 37·9-48·5). For the non-inferiority comparison of participants aged 3-17 years with those aged 18-59 years for SARS-CoV-2 neutralising antibodies, the adjusted GMR was 8·6 (95% CI 7·0-10·4), with the lower bound of the GMR greater than 0·67. INTERPRETATION: ZF2001 is safe, well tolerated, and immunogenic in children and adolescents aged 3-17 years. Vaccine-elicited sera can neutralise the omicron BA.2 subvariant, but with reduced activity. The results support further studies of ZF2001 in children and adolescents. FUNDING: Anhui Zhifei Longcom Biopharmaceutical and the Excellent Young Scientist Program from National Natural Science Foundation of China. TRANSLATION: For the Chinese translation of the abstract see Supplementary Materials section.

Prevalence and Potential Risk Factors for Occupational Low Back Pain Among Male Military Pilots: A Study Based on Questionnaire and Physical Function Assessment.

Objectives: Low back pain (LBP) has negative implications for the military's combat effectiveness. This study was conducted to determine the prevalence and risk factors of LBP among pilots through a questionnaire and physical function assessments. Methods: Data on the demographic and occupational characteristics, health habits, physical activity, and musculoskeletal injuries of 217 male pilots (114 fighter, 48 helicopter, and 55 transport pilots) were collected using a self-reported questionnaire and physical function assessments. Results: LBP prevalence was 37.8% in the total cohort and 36.0, 45.8, and 34.5% among fighter, helicopter, and transport pilots, respectively. Multivariate regression analysis revealed that the risk factors significantly associated with LBP were neck pain [odds ratio (OR): 3.559, 95% confidence interval (CI): 1.827-6.934], transversus abdominis activation (OR: 0.346, 95% CI: 0.172-0.698), and hip external rotator strength (OR: 0.001, 95% CI: 0.000-0.563) in the total cohort; neck pain (OR: 3.586, 95% CI: 1.365-9.418), transversus abdominis activation (OR: 0.268, 95% CI: 0.094-0.765), hip external rotator strength (OR: 0.000, 95% CI: 0.000-0.949), and weekly flying hours (OR: 3.889, 95% CI: 1.490-10.149) in fighter pilots; irregular strength training (OR: 0.036, 95% CI: 0.003-0.507) and hip external rotator strength (OR: 0.000, 95% CI: 0.000-0.042) in helicopter pilots; and neck pain (OR: 6.417, 95% CI: 1.424-28.909) in transport pilots. Conclusions: High volume flight schedules and weak core muscle functions have significant negative effects on pilots' back health. LBP is commonly associated with high weekly flying hours, worsening neck pain, transversus abdominis insufficient activation, and reduced hip extensor/rotator strength. Risk factors vary among pilots of different aircraft. Thus, specific core muscle training would be especially important for military pilots.

Salmonella enteritidis Hcp distribute in the cytoplasm and regulate TNF signaling pathway in BHK-21 cells.

Hemolysin-coregulated protein (Hcp) of Salmonella enteritidis is known to be a structural and effector protein of the T6SS, but little is known about the role of Hcp in host cells. In this study, Hcp was expressed by plasmid pEGFP-N1-hcp in BHK-21 cells and the results showed that the subcellular localization of Hcp was predominantly in the cytoplasm of BHK-21 cells. When Hcp was over-expressed by transfecting plasmid pCI-neo-hcp in BHK-21 cells and mRNA sequencing was performed to analyze differentially expressed genes, the results showed a change in the expression levels of 307 mRNAs (fold change > 2, and p < 0.01). Amongst these, 125 mRNAs were up-regulated and 182 mRNAs were down-regulated. Kyoto encyclopedia of genes and genomes (KEGG) enrichment analysis showed that differentially expressed genes were enriched in tumor necrosis factor (TNF) signaling pathway, IL-17 signaling pathway, and cytokine-cytokine receptor interaction. Subsequently, we selected differentially expressed genes of TNF signaling pathway and verified the changes by real-time PCR. The results were consistent with the trend observed for the sequencing results. In conclusion, we demonstrated that Hcp of Salmonella enteritidis caused the change of mRNAs expression of TNF signaling pathway in the cytoplasm of BHK-21 cells.

Comparative proteomics reveals protective effect of resveratrol on a high-fat diet-induced damage to mice testis.

In recent years, resveratrol has been shown to protect against metabolic damage, including obesity-associated subfertility/infertility. In the present study, proteomic alterations in testicular tissues were investigated by tandem mass tag (TMT) in mice fed with a high-fat diet (HFD) without or with resveratrol supplementation (HFD+RSV). Serum testosterone levels, spermatozoa parameters and testicular histological morphology were assessed. Resveratrol treatment was shown to significantly reduce serum cholesterol, prevent the HFD-induced reductions in serum testosterone and spermatozoa parameters, and decrease the ultrastructural degeneration of testicular tissues. The comparative proteomics analysis revealed 58 differentially expressed proteins between the HFD and control groups and 38 differentially expressed proteins between the HFD and HFD+RSV groups. Gene ontology (GO) term enrichment and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis revealed that the most highly enriched differential proteins were correlated to spermatozoa function and cholesterol metabolism. The real-time RT-PCR and western blotting results confirmed the differential expression of the corresponding proteins related to spermatozoa function that were identified by proteomics. The present study provides new insight into the mechanisms of the beneficial effects of resveratrol, and may present it as a potential therapeutic strategy for obesity-associated male subfertility/infertility.Abbreviations:TMT: Tandem mass tag; HFD: High-fat diet; RSV: Resveratrol; GO: Gene ontology; Protein-proteinKEGG: Kyoto Encyclopedia of Genes and Genomes; RT-PCR: Reverse transcription-polymerase chain reaction; SDS-PAGE: Sodium dodecyl sulfate-polyacrylamide gel electrophoresis; PVDF: Polyvinylidene fluoride; ECL: Enhanced chemiluminescence; RIPA: Radio-immunoprecipitation assay; CTRL: Control; PPI: interaction; RIA: Radioimmunoassay; T: Testosterone; TG: Triglycerides; TC: Total cholesterol; LDL-c: Low-density lipoprotein cholesterol; HDL-c: High-density lipoprotein cholesterol; Crisp1: Cysteine-rich secretory protein 1; SIRT1: Sirtuin 1; GPx5: Glutathione peroxidase 5; Svs4: Seminal vesicle secretory protein 4; Tssk3: Testis-specific serine kinase 3; Pate4: Prostate and testis expressed 4; Sva: Seminal vesicle antigen; Lcn5: Lipocalin 5; Spinkl: Serine protease inhibitor, Kazal type-like.

Melatonin appears to protect against steroidogenic collapse in both mice fed with high-fat diet and H2 O2 -treated TM3 cells.

High-fat diets (HFDs) are detrimental to steroidogenesis and male fertility. This study aimed to investigate the protective effects of melatonin (MT) treatment on testicular dysfunction in mice fed with HFD. C57BL/6J male mice were randomly divided into three groups: CTRL, HFD and HFD + MT. MT treatment mitigated the increase in body weight and adipose tissue in HFD-fed mice. Serum levels of sex hormones were improved upon MT supplementation, and the expression of the testosterone synthesis proteins, StAR and P450scc was rescued as well. MT treatment significantly up-regulated the expression of SIRT1, SOD2, and GPx4 and down-regulated the expression of GRP78 and CHOP, indicating an attenuation of oxidative stress (OS) and endoplasmic reticulum (ER) stress. In TM3 cells, MT treatment protected against H2 O2 -induced steroidogenic collapse by improving mitochondrial function and attenuating OS and ER stress. These results indicate that MT treatment can improve steroidogenesis in mice fed with HFD and may have therapeutic value in the treatment of obesity-associated hypogonadism.