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1.
《Vaccine》2022,40(27):3721-3726
We initiated a randomized, placebo-controlled, phase 1/2 trial to evaluate the safety and immunogenicity of the S-268019-b recombinant protein vaccine, scheduled as 2 intramuscular injections given 21 days apart, in 60 randomized healthy Japanese adults. We evaluated 2 regimens of the S-910823 antigen (5 μg [n = 24] and 10 μg [n = 24]) with an oil-in-water emulsion formulation and compared against placebo (n = 12). Reactogenicity was mild in most participants. No serious adverse events were noted. For both regimens, vaccination resulted in robust IgG and neutralizing antibody production at days 36 and 50 and predominant T-helper 1-mediated immune reaction, as evident through antigen-specific polyfunctional CD4+ T-cell responses with IFN-γ, IL-2, and IL-4 production on spike protein peptides stimulation. Based on the interim analysis, the S-268019-b vaccine is safe, produces neutralizing antibodies titer comparable with that in convalescent serum from COVID-19-recovered patients. However, further evaluation of the vaccine in a large clinical trial is warranted.  相似文献   
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《Vaccine》2022,40(7):1001-1009
Vaccination guidelines for dogs and cats indicate that core vaccines (for dogs, rabies, distemper, adenovirus, parvovirus; for cats, feline parvovirus, herpes virus-1, calicivirus) are essential to maintain health, and that non-core vaccines be administered according to a clinician’s assessment of a pet’s risk of exposure and susceptibility to infection. A reliance on individual risk assessment introduces the potential for between-practice inconsistencies in non-core vaccine recommendations. A study was initiated to determine non-core vaccination rates of dogs (Leptospira, Borrelia burgdorferi, Bordetella bronchiseptica, canine influenza virus) and cats (feline leukemia virus) in patients current for core vaccines in veterinary practices across the United States. Transactional data for 5,531,866 dogs (1,670 practices) and 1,914,373 cats (1,661 practices) were retrieved from practice management systems for the period November 1, 2016 through January 1, 2020, deidentified and normalized. Non-core vaccination status was evaluated in 2,798,875 dogs and 788,772 cats that were core-vaccine current. Nationally, median clinic vaccination rates for dogs were highest for leptospirosis (70.5%) and B. bronchiseptica (68.7%), and much lower for canine influenza (4.8%). In Lyme-endemic states, the median clinic borreliosis vaccination rate was 51.8%. Feline leukemia median clinic vaccination rates were low for adult cats (34.6%) and for kittens and 1-year old cats (36.8%). Individual clinic vaccination rates ranged from 0 to 100% for leptospirosis, B. bronchiseptica and feline leukemia, 0–96% for canine influenza, and 0–94% for borreliosis. Wide variation in non-core vaccination rates between clinics in similar geographies indicates that factors other than disease risk are driving the use of non-core vaccines in pet dogs and cats, highlighting a need for veterinary practices to address gaps in patient protection. Failure to implement effective non-core vaccination strategies leaves susceptible dogs and cats unprotected against vaccine-preventable diseases.  相似文献   
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《Vaccine》2016,34(39):4724-4731
Human papillomavirus (HPV) infection is the most common sexually transmitted disease worldwide. HPVs are oncogenic small double-stranded DNA viruses that are the primary causal agent of cervical cancer and other types of cancers, including in the anus, oropharynx, vagina, vulva, and penis. Prophylactic vaccination against HPV is an attractive strategy for preventing cervical cancer and some other types of cancers. However, there are few safe and effective vaccines against HPV infections. Current first-generation commercial HPV vaccines are expensive to produce and deliver.The goal of this study was to develop an alternate potent HPV recombinant L1-based vaccines by producing HPV virus-like particles into a vaccine that is currently used worldwide. Live attenuated measles virus (MV) vaccines have a well-established safety and efficacy record, and recombinant MV (rMV) produced by reverse genetics may be useful for generating candidate HPV vaccines to meet the needs of the developing world.We studied in non-human primate rMV-vectored HPV vaccine in parallel with a classical alum adjuvant recombinant HPV16L1 and 18L1 protein vaccine produced in Pichia pastoris. A combined prime-boost approach using both vaccines was evaluated, as well as immune interference due to pre-existing immunity against the MV.The humoral immune response induced by the MV, Pichia-expressed vaccine, and their combination as priming and boosting approaches was found to elicit HPV16L1 and 18L1 specific total IgG and neutralizing antibody titres. Pre-existing antibodies against measles did not prevent the immune response against HPV16L1 and 18L1.  相似文献   
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《Vaccine》2021,39(26):3498-3508
Adenovirus infections are a major cause of epidemic keratoconjunctivitis (EKC), which can lead to corneal subepithelial infiltrates and multifocal corneal opacity. In the current study, we investigated the use of an E1/E3-deleted adenovirus serotype 5 (Ad5) vector as a vaccine administered intramuscularly (IM) or intranasally (IN) against subsequent challenges with a luciferase-expressing Ad5 (Ad5-Luci) vector via eyedrop. We evaluated the adaptive immune response to Ad5 vector vaccination and confirmed a robust polyfunctional CD8 T cell response in splenic cells. Neutralizing Ad5 antibodies were also measured in the sera of vaccinated mice as well as Ad5 antibody in the eye wash solutions. Upon challenge with Ad5-Luci vector 8 weeks post the primary immunization, transduction was significantly reduced by > 70% in the vaccinated mice, which was slightly better in IM- vs. that in IN-vaccinated animals. Resistance to subsequent challenge was observed 10 months post primary IM vaccination, with sustained reduction up to 60% in the Ad5-Luci vector transduction. Passive immunization of naive mice with antisera from IM to vaccinated mice subsequently challenged with the Ad5-Luci vector resulted in approximately 40% loss in transduction efficiency. Furthermore, the mice that received IM immunization with or without CD8 T cell depletion showed > 40% and 70% reductions, respectively, in Ad8 genomic copies after Ad8 topical challenge. We conclude that Ad-vector vaccination successfully induced an adaptive immune response that prevented subsequent Ad transduction in the cornea and conjunctiva-associated tissues in a mouse model of adenovirus keratoconjunctivitis, and that both cellular and humoral immunity play an important role in preventing Ad transduction.  相似文献   
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《Vaccine》2019,37(31):4310-4317
ONRAB® is a human adenovirus rabies glycoprotein recombinant vaccine developed to control rabies in wildlife. To support licensing and widespread use of the vaccine, safety studies are needed to assess its potential residual impact on wildlife populations. We examined the persistence of the ONRAB® vaccine virus in captive rabies vector and non-target mammals. This research complements work on important rabies vector species (raccoon, striped skunk, and red fox) but also adds to previous findings with the addition of some non-target species (Virginia opossum, Norway rats, and cotton rats) and a prolonged period of post vaccination monitoring (41 days). Animals were directly inoculated orally with the vaccine and vaccine shedding was monitored using quantitative real-time PCR applied to oral and rectal swabs. ONRAB® DNA was detected in both oral and rectal swabs from 6 h to 3 days post-inoculation in most animals, followed by a resurgence of shedding between days 17 and 34 in some species. Overall, the duration over which ONRAB® DNA was detectable was shorter for non-target mammals, and by day 41, no animal had detectable DNA in either oral or rectal swabs. All target species, as well as cotton rats and laboratory-bred Norway rats, developed robust humoral immune responses as measured by competitive ELISA, with all individuals being seropositive at day 31. Similarly, opossums showed good response (89% seropositive; 8/9), whereas only one of nine wild caught Norway rats was seropositive at day 31. These results support findings of other safety studies suggesting that ONRAB® does not persist in vector and non-target mammals exposed to the vaccine. As such, we interpret these data to reflect a low risk of adverse effects to wild populations following distribution of ONRAB® to control sylvatic rabies.  相似文献   
8.
目的研究快速成型(RP)技术辅助下制作的个体化假体复合珊瑚羟基磷灰石(CHA)、重组人骨形成蛋白2(rhBMP-2)修复兔下颌骨缺损的成骨效果。 方法以27只新西兰大白兔为实验对象,随机数字表法平均分成3组(每组9只),全部建立下颌骨连续性缺损模型,并在兔下颌骨缺损区分别植入个体化假体+自体骨(A组)、个体化假体+CHA(B组)、个体化假体+CHA+rhBMP-2(C组)。分别于术后4、12、24周3个时间点处死动物取材,进行大体标本观察,以及骨钙素(OC)、Ⅰ型胶原(COL-1)的免疫组化观察,分别比较各组修复骨缺损的能力,并对实验数据进行重复测量设计资料的单因素方差分析。 结果术后24周各组实验兔外形均对称,通过OC及COL-1的吸光度检测,骨缺损区均有大量新骨形成,A组(0.537 ± 0.010)、C组(0.530 ± 0.010)可见大量骨小梁及编织骨结构,缺损区的新骨OC、COL-1的免疫组化观察基本一致,差异无统计学意义(t = 0.007,P>0.05);但A组强于B组(0.415 ± 0.009,t = 0.122,P<0.001);C组也强于B组(t = 0.121,P<0.001),差异均有统计学意义。 结论在兔下颌骨缺损修复中,通过RP技术和组织工程技术相结合,CHA复合rhBMP-2后成骨能力明显增强,成骨效能肯定,为后期的临床应用提供可靠的实验基础。  相似文献   
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Fetal activity parameters such as movements, heart rate and the related parameters are essential indicators of fetal wellbeing, and no device provides simultaneous access to and sufficient estimation of all of these parameters to evaluate fetal health. This work was aimed at collecting these parameters to automatically separate healthy from compromised fetuses. To achieve this goal, we first developed a multi-sensor–multi-gate Doppler system. Then we recorded multidimensional Doppler signals and estimated the fetal activity parameters via dedicated signal processing techniques. Finally, we combined these parameters into four sets of parameters (or four hyper-parameters) to determine the set of parameters that is able to separate healthy from other fetuses. To validate our system, a data set consisting of two groups of fetal signals (normal and compromised) was established and provided by physicians. From the estimated parameters, an instantaneous Manning-like score, referred to as the ultrasonic score, was calculated and was used together with movements, heart rate and the associated parameters in a classification process employing the support vector machine method. We investigated the influence of the sets of parameters and evaluated the performance of the support vector machine using the computation of sensibility, specificity, percentage of support vectors and total classification error. The sensitivity of the four sets ranged from 79% to 100%. Specificity was 100% for all sets. The total classification error ranged from 0% to 20%. The percentage of support vectors ranged from 33% to 49%. Overall, the best results were obtained with the set of parameters consisting of fetal movement, short-term variability, long-term variability, deceleration and ultrasound score. The sensitivity, specificity, percentage of support vectors and total classification error of this set were respectively 100%, 100%, 35% and 0%. This indicated our ability to separate the data into two sets (normal fetuses and pathologic fetuses), and the results highlight the excellent match with the clinical classification performed by the physicians. This work indicates the feasibility of detecting compromised fetuses and also represents an interesting method of close fetal monitoring during the entire pregnancy.  相似文献   
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