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11.
Early life adversity impacts on a range of emotional, cognitive, and psychological processes. A recent theoretical model suggests that at least some of these effects are due to accelerated maturation of specific physiological systems and/or neural circuits. For example, maternal separation (MS), a model of early life adversity in rodents, accelerates maturation of memory systems, and here we examined its impact on maturation of perineuronal nets (PNNs) and parvalbumin (PV)-containing inhibitory interneurons. PNNs are specialized extracellular matrix structures suggested to be involved in stabilizing long-term memories and in the closure of a sensitive period in memory development. PV-containing inhibitory interneurons are the type of cell that PNNs preferentially surround, and are also thought to be involved in memory. In Experiment 1, with male rats, there was an increase in PNNs in both the amygdala and prefrontal cortex with age from infancy to juvenility. Contrary to prediction, MS had no impact on either PNN or PV expression. The same pattern was observed in female rats in Experiment 2. Taken together, these data show that the early maturation of memory in MS infants is not due to an accelerated maturation of PNNs or PV-containing cells in either the amygdala or prefrontal cortex.  相似文献   
12.
目的:探讨血清p53抗体异常高水平对消化道肿瘤的早期诊断的价值。方法:选取2016年3月至2019年3月来我院检查确诊为消化道肿瘤的患者80例为消化道肿瘤组,选取来我院健康体检的67例健康志愿者为健康对照组。通过酶联免疫吸附实验检测血清中人体抑癌基因p53及其抗体水平;通过RT-qPCR检测血清中细胞凋亡相关基因Bcl-2、Bax和Caspase-3蛋白表达量。采用Pearson相关性分析明确消化道肿瘤p53、p53抗体水平和Bcl-2、Bax、Caspase-3蛋白表达水平的关系。结果:消化道肿瘤组p53水平降低,p53抗体水平异常升高(P<0.05)。与健康对照组相比,消化道肿瘤组Bcl-2表达量增加,Bax和Caspase-3蛋白表达量降低(P<0.05)。消化道肿瘤p53水平与Bcl-2蛋白表达水平呈负相关关系,与Bax、Caspase-3蛋白表达水平均呈正相关关系;p53抗体水平和Bcl-2蛋白表达水平呈正相关关系,与Bax、Caspase-3蛋白表达水平均呈负相关关系(P<0.05)。结论:消化道肿瘤患者血清p53抗体异常高水平,可作为临床辅助诊断消化道肿瘤的可靠指标之一。  相似文献   
13.
《Vaccine》2021,39(45):6601-6613
AKS-452 is a biologically-engineered vaccine comprising an Fc fusion protein of the SARS-CoV-2 viral spike protein receptor binding domain antigen (Ag) and human IgG1 Fc (SP/RBD-Fc) in clinical development for the induction and augmentation of neutralizing IgG titers against SARS-CoV-2 viral infection to address the COVID-19 pandemic. The Fc moiety is designed to enhance immunogenicity by increasing uptake via Fc-receptors (FcγR) on Ag-presenting cells (APCs) and prolonging exposure due to neonatal Fc receptor (FcRn) recycling. AKS-452 induced approximately 20-fold greater neutralizing IgG titers in mice relative to those induced by SP/RBD without the Fc moiety and induced comparable long-term neutralizing titers with a single dose vs. two doses. To further enhance immunogenicity, AKS-452 was evaluated in formulations containing a panel of adjuvants in which the water-in-oil adjuvant, Montanide™ ISA 720, enhanced neutralizing IgG titers by approximately 7-fold after one and two doses in mice, including the neutralization of live SARS-CoV-2 virus infection of VERO-E6 cells. Furthermore, ISA 720-adjuvanted AKS-452 was immunogenic in rabbits and non-human primates (NHPs) and protected from infection and clinical symptoms with live SARS-CoV-2 virus in NHPs (USA-WA1/2020 viral strain) and the K18 human ACE2-trangenic (K18-huACE2-Tg) mouse (South African B.1.351 viral variant). These preclinical studies support the initiation of Phase I clinical studies with adjuvanted AKS-452 with the expectation that this room-temperature stable, Fc-fusion subunit vaccine can be rapidly and inexpensively manufactured to provide billions of doses per year especially in regions where the cold-chain is difficult to maintain.  相似文献   
14.
Since the 1990s, oral rabies vaccination (ORV) has been used successfully to halt the westward spread of the raccoon rabies virus (RV) variant from the eastern continental USA. Elimination of raccoon RV from the eastern USA has proven challenging across targeted raccoon (Procyon lotor) and striped skunk (Mephitis mephitis) populations impacted by raccoon RV. Field trial evaluations of the Ontario Rabies Vaccine Bait (ONRAB) were initiated to expand ORV products available to meet the rabies management goal of raccoon RV elimination. This study describes the continuation of a 2011 trial in West Virginia. Our objective was to evaluate raccoon and skunk response to ORV occurring in West Virginia for an additional two years (2012–2013) at 75 baits/km2 followed by three years (2014–2016) of evaluation at 300 baits/km2. We measured the change in rabies virus-neutralizing antibody (RVNA) seroprevalence in targeted wildlife populations by comparing levels pre- and post-ORV during each year of study. The increase in bait density from 75/km2 to 300/km2 corresponded to an increase in average post-ORV seroprevalence for raccoon and skunk populations. Raccoon population RVNA levels increased from 53% (300/565, 95% CI: 50–57%) to 82.0% (596/727, 95% CI: 79–85%) during this study, and skunk population RVNA levels increased from 11% (8/72, 95% CI: 6–20%) to 39% (51/130, 95% CI: 31–48%). The RVNA seroprevalence pre-ORV demonstrated an increasing trend across study years for both bait densities and species, indicating that multiple years of ORV may be necessary to achieve and maintain RVNA seroprevalence in target wildlife populations for the control and elimination of raccoon RV in the eastern USA.  相似文献   
15.
《Vaccine》2021,39(14):1933-1942
The genetic and antigenic drift associated with the high pathogenicity avian influenza (HPAI) viruses of Goose/Guangdong (Gs/GD) lineage and the emergence of vaccine-resistant field viruses underscores the need for a broadly protective H5 influenza A vaccine. Here, we tested experimental vector herpesvirus of turkey (vHVT)-H5 vaccines containing either wild-type clade 2.3.4.4A-derived H5 inserts or computationally optimized broadly reactive antigen (COBRA) inserts with challenge by homologous and genetically divergent H5 HPAI Gs/GD lineage viruses in chickens. Direct assessment of protection was confirmed for all the tested constructs, which provided clinical protection against the homologous and heterologous H5 HPAI Gs/GD challenge viruses and significantly decreased oropharyngeal shedding titers compared to the sham vaccine. The cross reactivity was assessed by hemagglutinin inhibition (HI) and focus reduction assay against a panel of phylogenetically and antigenically diverse H5 strains. The COBRA-derived H5 inserts elicited antibody responses against antigenically diverse strains, while the wild-type-derived H5 vaccines elicited protection mostly against close antigenically related clades 2.3.4.4A and 2.3.4.4D viruses. In conclusion, the HVT vector, a widely used replicating vaccine platform in poultry, with H5 insert provides clinical protection and significant reduction of viral shedding against homologous and heterologous challenge. In addition, the COBRA-derived inserts have the potential to be used against antigenically distinct co-circulating viruses and future drift variants.  相似文献   
16.
《Vaccine》2022,40(8):1128-1134
BackgroundOver the last 2 decades, Haemophilus influenzae type a (Hia) has emerged as a significant cause of invasive disease in some geographic regions and populations. Recognition of the importance of Hia in the etiology of serious disease, particularly in young children, prompted the development of a new protein-capsular polysaccharide conjugate vaccine, similar in design to a vaccine against H. influenzae type b. At present, understanding of Hia immunology is incomplete; the immunological correlate of protection against invasive disease is unknown.MethodsOur objective was to study Hia antibody in children of various ages residing in a Canadian province with low incidence rates of invasive disease. The enzyme-linked immunosorbent assays were performed to quantify plasma IgG and IgM specific to Hia capsular polysaccharide in 133 children (3 months to 16 years).ResultsBoth anti-Hia IgG and IgM concentrations increased with age and were significantly higher in older children; a positive correlation between age and concentrations of Hia antibody was found. IgM antibody concentrations were significantly higher than IgG, with mean IgM concentrations over 10 times larger than IgG across all age groups.ConclusionsThe steady rise of naturally acquired, Hia-specific IgG and IgM concentrations in a pediatric population with low incidence rates of invasive Hia disease suggests the exposure to some cross-reactive environmental antigens as a major source of the antibody. However, the carriage rates of Hia in the region are unknown and further seroepidemiological studies are warranted. Although natural antibody may protect certain population groups against invasive disease, immunization of younger children will be essential to prevent serious infections if Hia continues to spread across North America.  相似文献   
17.
《Molecular therapy》2022,30(5):1952-1965
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18.
《Vaccine》2022,40(33):4889-4896
BackgroundDuring the COVID-19 pandemic, the number of hepatitis B virus (HBV) vaccinations among men who have sex with men (MSM) has been considerably lower than before the pandemic. Moreover, less frequent HBV testing and a reduction in numbers of sex partners have been reported. We assessed the impact of these COVID-19-related changes on HBV transmission among MSM in the Netherlands.MethodsWe estimated the changes in sexual activity, HBV testing, and HBV vaccination among MSM during the pandemic from Dutch data. We used a deterministic compartmental model and investigated scenarios with small or large declines in sexual activity, testing, and vaccination for the current phase of the pandemic (without available data). We examined the increase in HBV vaccinations needed to prevent further increase in HBV incidence.ResultsWith a decrease in numbers of sex partners of 15–25% during the first lockdown and 5% during the second lockdown, we found a decline of 6.6% in HBV incidence in 2020, despite a >70% reduction in HBV testing and vaccination during the first lockdown. With numbers of sex partners rebounding close to pre-pandemic level in 2021, and a reduction of 15% in testing and 30% in vaccination in 2021, we found an increase of 1.4% in incidence in 2021 and 3.1% in 2026. With these changes, an increase of ≥60% in HBV vaccinations in 2022 would be needed to bring the HBV incidence in 2023 back to the level that it would have had if the COVID-19-related changes had not occurred.ConclusionsDespite reductions in sexual activity during the COVID-19 pandemic, the decrease in HBV vaccinations may result in a small increase in HBV incidence after 2021, which may persist for years. It is important to restore the vaccination level and limit further increase in HBV transmission among MSM.  相似文献   
19.
20.
《Vaccine》2022,40(24):3380-3388
BackgroundWe evaluated the safety and immunogenicity of NVX-CoV2373, a recombinant SARS-CoV-2 nanoparticle vaccine, in healthy Japanese participants.MethodsThis phase 1/2, randomized, observer-blind, placebo-controlled trial conducted in Japan (two sites), enrolled healthy Japanese adults aged ≥ 20 years with no history/risk of SARS-CoV-2 infection and no prior exposure to other approved/investigational SARS-CoV-2 vaccines or treatments. Participants were stratified by age (< 65 or ≥ 65 years) and randomized to receive two doses of either NVX-CoV2373 (5 μg SARS-CoV-2 rS; 50 μg Matrix-M1) or placebo, 21 days apart. Primary outcomes were safety and immunogenicity assessed by serum IgG antibody levels against SARS-CoV-2 rS protein on day 36. Herein, we report the primary data analysis at 4 weeks after the second dose, ahead of 12-month follow-up completion (data cut-off: 8 May 2021).ResultsBetween 12 February 2021 and 17 March 2021, 326 subjects were screened, and 200 participants enrolled and randomized: NVX-CoV2373, n = 150; placebo, n = 50. Solicited adverse events (AEs) through 7 days after each injection occurred in 121/150 (80.7%) and 11/50 (22.0%) participants in the NVX-CoV2373 and placebo arms, respectively. In the NVX-CoV2373 arm, tenderness and injection site pain were the most frequently reported solicited AEs after each vaccination, irrespective of age. Robust immune responses occurred with NVX-CoV2373 (n = 150) by day 36: IgG geometric mean fold rise (95% confidence interval) 259 (219, 306); seroconversion rate 100% (97.6, 100). No such response occurred with placebo (n = 49).ConclusionTwo doses of NVX-CoV2373 given with a 21-day interval demonstrated acceptable safety and induced robust anti-SARS-CoV-2 immune responses in healthy Japanese adults. Funding: Takeda Pharmaceutical Company Limited and Japan Agency for Medical Research and Development (AMED). ClinicalTrials.gov identifier: NCT04712110.  相似文献   
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