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1.
《Vaccine》2022,40(32):4440-4452
Coronavirus disease 2019 (COVID-19) is an acute respiratory illness caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The prevention of SARS-CoV-2 transmission has become a global priority. Previously, we showed that a protein subunit vaccine that was developed based on the fusion of the SARS-CoV-2 receptor-binding domain (RBD) to the Fc portion of human IgG1 (RBD-Fc), produced in Nicotiana benthamiana, and adjuvanted with alum, namely, Baiya SARS-CoV-2 Vax 1, induced potent immunological responses in both mice and cynomolgus monkeys. Hence, this study evaluated the protective efficacy, safety, and toxicity of Baiya SARS-CoV-2 Vax 1 in K18-hACE2 mice, monkeys and Wistar rats. Two doses of vaccine were administered three weeks apart on Days 0 and 21. The administration of the vaccine to K18-hACE2 mice reduced viral loads in the lungs and brains of the vaccinated animals and protected the mice against challenge with SARS-CoV-2. In monkeys, the results of safety pharmacology tests, general clinical observations, and a core battery of studies of three vital systems, namely, the central nervous, cardiovascular, and respiratory systems, did not reveal any safety concerns. The toxicology study of the vaccine in rats showed no vaccine-related pathological changes, and all the animals remained healthy under the conditions of this study. Furthermore, the vaccine did not cause any abnormal toxicity in rats and was clinically tolerated even at the highest tested concentration. In addition, general health status, body temperature, local toxicity at the administration site, hematology, and blood chemistry parameters were also monitored. Overall, this work presents the results of the first systematic study of the safety profile of a plant-derived vaccine, Baiya SARS-CoV-2 Vax 1; this approach can be considered a viable strategy for the development of vaccines against COVID-19. 相似文献
2.
【摘要】 报道临床症状不典型的家族性黑棘皮病1家系。先证者女,4岁,自1周岁时,颈部、腹部出现黑色斑片,近年来逐渐扩大至唇周、躯干前部。腹部皮肤全反式共聚焦显微镜检查可见乳头环下延扭曲及沟壑结构,乳头环内可见中高折光颗粒结构。先证者父亲及祖母既往有类似病史,但随着年龄增长色素沉着自发性消退,仅有局部皮纹增粗。采集先证者及父母、祖母外周血,对先证者外周血DNA行Panel靶向测序,结果显示,先证者存在FGFR3基因14号外显子c.1949A>C(p.Lys650Thr)错义突变,Sanger测序验证证实先证者及其父亲和祖母均存在此突变。诊断:家族性黑棘皮病。 相似文献
3.
The objective of this study was to determine whether the development of tolerance to CP 55,940, a potent cannabinoid agonist, was due to changes in the receptor or second messenger system. ICR mice treated with CP 55,940 (2 mg/kg) twice a day for 6 and one-half days developed a high degree of tolerance to the pharmacological effects of CP 55,940. The ability of CP 55,940 to produce motor hypoactivity, hypothermia and immobility was reduced 163-, 97- and 19-fold, respectively. Evaluation of 3H-CP 55,940 binding to rat brain membranes indicated no difference in receptor affinity between the vehicle- and CP 55,940-treated animals. However, these binding studies revealed a 50% decrease in receptor number in the cerebellum of the CP 55,940-tolerant mice. Although cAMP is generally considered to be the second messenger for cannabinoid receptors, little difference was observed in the inhibitory effects of CP 55,940 on adenylyl cyclase activity in cerebellum between vehicle and drug-treated mice. However, there was an increase in receptor mRNA which suggests a compensation for receptor loss. There are several possible explanations for these results. There may be sufficient spare receptors such that CP 55,940-tolerant mice are capable of producing a maximal effect on the second messenger system. On the other hand, one could conclude that cannabinoid receptor down-regulation does not account for the development of tolerance to all of the effects of CP 55,940 in mice. 相似文献
4.
前列腺带性结构及其雄激素、雌激素、表皮生长因子受体分布特征的研究 总被引:2,自引:0,他引:2
为了探讨雄激素受体(AR)、雌激素受体(ER)、孕激素受体(PR)和表皮生长因子受体(EGFR)在前列腺带性结构中的分布,应用单饱和剂量测定法,分别测定了前列腺移行带、外周带组织中AR、ER、PR和EGFR的含量。结果表明,在11例前列腺增生症(BPH)患者22份标本中,移行带和周围带AR全部阳性;尽管AR浓度个体差异很大,但是两带之间仍有密切相关性(P<0001);周围带AR浓度高于移行带,两带AR浓度均高于PR、ER;PR和ER在前列腺带性结构上没有明显差异。EGFR在移行带明显高于周围带。研究证实了AR、ER、PR,EGFR在前列腺移行带和周围带上的分布特征。 相似文献
5.
Groups of male CF-1 mice received 3 and 10 µmol/kg diazepam, lorazepam, and oxazepam intravenously. Between 1 min and 24 h after injection, benzodiazepine concentrations were determined by gas chromatography (GLC) in plasma and in one brain hemisphere; in the other hemisphere, ex vivo benzodiazepine receptor occupancy was measured using3H-flunitrazepam displacement. Based on GLC data, diazepam entered brain rapidly, and was also cleared rapidly, yielding desmethyldiazepam and oxazepam as metabolites in plasma and brain. However, lorazepam and oxazepam entered brain slowly, with brain:plasma equilibrium achieved at 30–60 min; thereafter, the drugs were eliminated from plasma and brain in parallel. The time course and extent of ex vivo occupancy were highly consistent with GLC data (for diazepam, GLC levels were expressed as the sum of diazepam, desmethyldiazepam, and oxazepam, with metabolite concentrations, normalized for molecular weight and for in vitro benzodiazepine receptor affinity.) Between-method correlations were 0.95 or higher. Thus benzodiazepine receptor occupancy is highly dependent on benzodiazepine concentrations in brain. Differences in the time-course of onset and duration of pharmacologic activity between the highly lipophilic benzodiazepine diazepam and the less lipophilic hydroxylated derivatives lorazepam and oxazepam are largely explained by differences in systemic kinetics and in the rate of uptake into brain.Supported in part by grants MH-34223, DA-05258, and AG-00106 from the United States Public Health Service 相似文献
6.
压力性尿失禁的病因学研究 总被引:4,自引:0,他引:4
目的 绝经后压力性尿失禁 (SUI)患者补充雌激素的临床疗效尚有争议。本研究通过对血雌二醇 (E2 )浓度及子宫韧带的雌激素受体 (ER)的观察 ,分析雌激素与SUI和盆底组织膨出 (POP)发生的关系。方法 绝经前、后对照组、POP组和绝经后SUI组共 5组 73例子宫全切患者 ,免疫组化方法测定主韧带、宫骶韧带ER含量。结果 ( 1)绝经前POP组血E2 浓度 ( 4 7.2 9pg ml± 38.30pg ml)、韧带ER值明显低于绝经前对照组 (E2 73.83pg ml± 5 2 .72pg ml;ER主韧带9.5 8%± 2 .39% ,ER宫骶韧带11.6 4 %±2 .6 8% ) ,差异非常显著 (P <0 .0 1)。 ( 2 )绝经后韧带ER值 :对照组 (ER主韧带10 .89%± 2 .5 4 % ,ER宫骶韧带13.0 9%± 3.0 3% )、POP组 (ER主韧带11.85 %± 2 .89% ,ER宫骶韧带13.2 1%± 3.4 6 % )及SUI组 (ER主韧带9.6 4 %± 5 .0 1% ,ER宫骶韧带11.12 %± 6 .13% )之间无显著差异 ( P >0 .0 5 )。 ( 3)绝经前、后对照组韧带ER值无显著差异 (P >0 .0 5 )。绝经前对照组月经增生期、分泌期韧带ER值无显著差异 (P >0 .0 5 )。血E2 浓度与韧带ER值无相关性。 ( 4 )绝经后对照组绝经时间与主韧带ER值成正相关 ,与宫骶韧带ER值无相关性。绝经后POP组和SUI组主韧带、宫骶韧带ER值与绝经时间成正相关。 ( 5 )各组研究对? 相似文献
7.
花生凝集素受体在鼻息肉组织中的表达及意义 总被引:1,自引:1,他引:0
目的 :探讨花生凝集素受体在鼻息肉组织中的表达及意义。方法 :将 2 4例鼻息肉标本及 15例正常鼻窦黏膜标本行凝集素亲合组织化学ABC法染色。结果 :正常鼻息肉黏膜染色基本阴性 ,鼻息肉呈弱染色。N -PNA(预先经神经氨酸酶处理后再进行PNA染色 )染色均显著加深。结论 :从正常鼻窦黏膜到鼻息肉 ,花生凝集素受体的表达发生改变 ,该种改变在鼻息肉的病理机制中可能起着重要作用 相似文献
8.
雷帕霉素对炎性反应状态下肾小球系膜细胞内脂质稳态的影响 总被引:2,自引:1,他引:1
Objective To investigate the effect of rapamycin on cholesterol homeostasis of glomerular mesangial cells and the underlying mechanism. Methods Glomerular mesangial cell line (HMCL) cells were cultured and divided into control group, IL-1β group and different concentration rapamycin groups. Intracellular cholesterol accumulation was observed and measured by oil O staining and HPLC. Real-time quantitative PCR and Western blot were used to detect the mRNA and protein expression of LDLR, PPARγ, LXRα, ABCA1 in HMCL after the treatment with IL-1β and rapamycin. Results Rapamycin had no significant influence on intracellular cholesterol concentration under normal condition. IL-1β significantly increased the intracellular cholesterol concentration by 143% of control (P<0.05), and 10, 50, 100 ?滋g/L rapamycin could significantly inhibit the effect of IL-1β (87%, 116%, 96% of control respectively, all P<0.05). Rapamycin could suppress the increased expression of LDLR caused by IL-1β on both mRNA and protein level in a dose-dependent manner(P<0.01). Rapamycin dose-dependently up-regulated the reduced mRNA and protein expression of ABCA1, the decreased mRNA expression of PPARγ and LXRα induced by IL-1β as well (P<0.01). Conclusion Rapamycin may contribute to the maintenance of intracellular cholesterol homeostasis in glomerular mesangial cells under inflammatory state by both reducing cholesterol uptake and promoting cholesterol efflux. 相似文献
9.
目的 观察重组人骨形成蛋白2(recombined human bone morphogenetic protein2,rhBMP-2)异位诱导成骨过程中神经生长因子(nerve growth factor,NGF)及其高亲和力受体(tyrosine kinasere ceptor A,TrkA)的表达,探讨NGF在BMP骨诱导中的作用。方法ICR小鼠36只,随机分为实验组和对照组,每组18只,均制备右侧股后部肌袋异位成骨模型。实验组植入含rhBMP-2胶原复合物,对照组仅植入相同体积的胶原海绵。分别于术后7、14和21d取材,行大体、组织学、免疫组织化学观察及RT-PCR检测。结果大体观察实验组术后7d,右股后部可扪及较硬肿块;术后14、21d,肿块硬度增加。对照组各时间点未发现肿块。组织学观察实验组中rhBMP-2胶原复合物具有良好的诱导成骨能力,免疫组织化学结果显示骨诱导材料植入后7d,NGF于成纤维细胞、成软骨细胞、软骨细胞、肥大软骨细胞和成骨细胞中均有阳性表达;14d,NGF阳性表达局限于部分成骨细胞、幼稚骨细胞和成骨样细胞,同时在骨髓中单核巨噬细胞、多核巨噬细胞和破骨细胞中有明显表达;21d,只有少量成骨样细胞和破骨细胞以及骨髓中多核巨噬细胞有NGF表达;TrkA免疫组织化学染色与NGF的表达基本一致。对照组术后各时间点未见成骨现象。实验组NGFmRNA的RT-PCR检测显示,术后7dNGF的mRNA表达最高,14d表达下降,21d只有微量表达。结论rhBMP-2复合物是一种有效的诱导成骨材料。在外源性BMP诱导成骨过程中有明显的NGF及其高亲和力受体TrkA的表达,NGF可以通过直接和间接的方式参与BMP的诱导成骨过程。 相似文献
10.
作者分别用差速离心法及蔗糖梯度离心法制备胎盘微绒毛膜(PMM),用受体放射分析法研究了PMM的转铁蛋白受体(TfB),结果表明:两种方法制备的PMM均可用于受体分析,但差速离心法更为简便。测定60例产妇PMM的TfR,其数目为3.53±1.98×10~(12)个位点/mg膜蛋白,最大结合容量为6.33±4.21×10~(-12)mol/mg膜蛋白,Kd值为4.95±3.39×10~(-9)mol/L。受体结合反应体系最适实验条件为,膜蛋白浓度每管50μg,标记物浓度每管50 000cpm,孵育30分钟,B/F分离的聚乙二醇浓度为12%(W/V)。对TfR的特性研究表明:TfR与转铁蛋白的结合具有高度亲和力、高度特异性及可饱和性。 相似文献