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《Vaccine》2022,40(16):2370-2378
Porcine reproductive and respiratory syndrome virus (PRRSV) and Mycoplasma hyopneumoniae (M. hyopneumoniae, Mhp) are two of the most common pathogens involved in the porcine respiratory disease complex (PRDC) resulting in significant economic losses worldwide. Vaccination is the most effective approach to disease prevention. Since PRRSV and Mhp co-infections are very common, an efficient dual vaccine against these pathogens is required for the global swine industry. Compared with traditional vaccines, multi-epitope vaccines have several advantages, they are comparatively easy to produce and construct, are chemically stable, and do not have an infectious potential. In this study, to develop a safe and effective vaccine, B cell and T cell epitopes of PRRSV-GP5, PRRSV-M, Mhp-P46, and Mhp-P65 protein had been screened to construct a recombinant epitope protein rEP-PM that has good hydrophilicity, strong antigenicity, and high surface accessibility, and each epitope is independent and complete. After immunization in mice, rEP-PM could induce the production of high levels of antibodies, and it had good immunoreactivity with anti-rEP-PM, anti-PRRSV, and anti-Mhp antibodies. The anti-rEP-PM antibody specifically recognizes proteins from PRRSV and Mhp. Moreover, rEP-PM induced a Th1-dominant cellular immune response in mice. Our results showed that the rEP-PM protein could be a potential candidate for the development of a safe and effective multi-epitope peptide combined vaccine to control PRRSV and Mhp infections.  相似文献   
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目的制备具有表面金壳以聚乳酸羟基乙酸(PLGA)为载体包载全氟溴辛烷(PFOB)和四氧化三铁(SPIOs)的纳米粒子,用于探究其体外超声显像和磁共振成像能力和光热杀伤肿瘤细胞效果。方法采用单乳化水包油(O/W)溶剂挥发法制备PFOB-SPIOs@PLGA纳米粒子,金种子生长法形成纳米粒子表面金壳制备;对其进行表征;通过CCK-8法评估纳米粒子的细胞毒性情况;采用超声和磁共振成像仪器观察纳米粒子的体外成像效果;近红外激光照射纳米粒子溶液观测升温效果;AM单染在激光共聚焦下观察光热杀伤肿瘤细胞效果。结果成功制备了PFOB-SPIOs@PLGA@Au纳米粒子,纳米粒子平均粒径(347±65.8)nm,粒径均一,分散性好;磁共振测得r2值为(465.23±30.39)mM-1s-1,具有体外磁共振T2成像效果;具有体外超声成像效果;近红外激光照射纳米粒子溶液10min最高温度可达45.2℃;CCK-8法检测纳米粒子对各组细胞存活率无明显影响。结论成功制备了粒径均一的PFOB-SPIOs@PLGA@Au纳米粒子,该纳米粒子具有较好的超声和磁共振T2体外成像效果和体外升温效果,且无明显细胞毒性。  相似文献   
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Hericium novae-zealandiae is a native mushroom consumed by indigenous Māori people in New Zealand. The lipophilic mycochemicals of the mushroom were isolated using a normal column chromatography combined with a preparative HPLC. Structural characterisation based on spectroscopic methods, namely UV, MS, NMR and single crystal XRD have identified three lipophilic compounds as hericene B (a compound unique to Hericium), ergosterol and ergosterol peroxide. Following this, an HPLC-DAD method was developed and validated to quantify the hericene B and ergosterol. The method showed excellent selectivity, linearity, precision, accuracy and robustness. The content of hericene B was determined as 28.53 mg/g by dry weight of H. novae-zealandiae (approximately 3%). This discovery indicates the potential utilisation of H. novae-zealandiae as a natural source of hericene B. Current research revealed for the first time, the lipophilic constituents of H. novae-zealandiae and the method development for quantification of hericene B in the above species.  相似文献   
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《Vaccine》2020,38(52):8362-8370
BackgroundCommunity-acquired pneumonia (CAP) is one of the major global health problems worldwide. However, the epidemiological information of CAP is limited in China. This study aimed to estimate the incidence rate of CAP and describe the epidemiologic characteristics among the Chinese population.MethodsWe conducted a retrospective analysis of CAP incidence using the Chinese Urban Basic Medical Insurance database of 23 provinces in 2016, which covered 427.52 million urban beneficiaries of all age groups in Mainland China. CAP episodes were identified using a diagnosis-term-derived algorithm, and multiple CAP records of one single person within 90 continuous days were considered as one single episode. The incidence rates were calculated and described by sex, age, region, and season.ResultsA total of 1.42 million patients were identified as having one or more CAP episodes, and finally a sum of 1.48 million CAP episodes were counted. The overall incidence of CAP was 7.13 (95% CI: 6.11–8.15) per 1000 person-years, in males 7.32 (95% CI: 6.28–8.35) and females 6.93 (95% CI: 5.92–7.94) per 1000 person-years, respectively. The incidence varied by age with a U-shaped curve peaking in children aged < 5 years old [65.80 (95% CI: 62.52–69.08)] and elderly population aged ≥ 80 years old [14.98 (95% CI: 13.63–16.34)]. The incidence varied markedly by regions. Furthermore, the rate showed a clear seasonal trend, which peaked in spring, decreased in summer and autumn, and re-ascended in winter.ConclusionThis study reveals a relatively high level of CAP incidence in China. These findings provide baseline data for establishing effective prevention strategies, targeted at susceptible populations, regions, and seasons in China.  相似文献   
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