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11.
12.
《Saudi Pharmaceutical Journal》2022,30(5):595-604
Anthrax is a zoonotic infection caused by the gram-positive, aerobic, spore-forming bacterium Bacillus anthracis. Depending on the origin of the infection, serious health problems or mortality is possible. The virulence of B. anthracis is reliant on three pathogenic factors, which are secreted upon infection: protective antigen (PA), lethal factor (LF), and edema factor (EF). Systemic illness results from LF and EF entering cells through the formation of a complex with the heptameric form of PA, bound to the membrane of infected cells through its receptor. The currently available anthrax vaccines have multiple drawbacks, and recombinant PA is considered a promising second-generation vaccine candidate. However, the inherent chemical instability of PA through Asn deamidation at multiple sites prevents its use after long-term storage owing to loss of potency. Moreover, there is a distinct possibility of B. anthracis being used as a bioweapon; thus, the developed vaccine should remain efficacious and stable over the long-term. Second-generation anthrax vaccines with appropriate adjuvant formulations for enhanced immunogenicity and safety are desired. In this article, using protein engineering approaches, we have reviewed the stabilization of anthrax vaccine candidates that are currently licensed or under preclinical and clinical trials. We have also proposed a formulation to enhance recombinant PA vaccine potency via adjuvant formulation. 相似文献
13.
《Vaccine》2022,40(32):4296-4300
Advanced computational methodologies suggested SARS-CoV-2, nonstructural proteins ORF1AB, ORF3a, as the source of immunodominant peptides for T cell presentation. T cell immunity is long-lasting and compatible with COVID-19 pathology. Based on the supporting clinical data, nonstructural SARS-CoV-2 protein vaccines could provide global immunity against COVID-19. 相似文献
14.
《Advances in medical sciences》2022,67(2):262-268
PurposeEpidermal hyperplasia and the involvement of immune cells characterize the clinical picture of psoriasis. Among the several factors involved, attention has been focused on sirtuin 1 (SIRT1) - a deacetylase endowed with a variety of functions including the control of metabolic and inflammatory processes-, and on nicotinamide phosphoribosyltransferase (NAMPT), important for SIRT1 activation and involved in inflammatory events. The aim of the study was to analyze changes of SIRT1 and NAMPT expression in psoriatic skin.Patients and methodsSamples from healthy controls and psoriatic patients were subjected to immunohistochemical analysis.ResultsA strong downregulation of SIRT1 expression was observed in skin samples from psoriatic patients compared to healthy controls. This was accompanied by a parallel reduction of adenosine monophosphate-activated kinase (AMPK) expression and, more strikingly, by the disappearance of cells immunolabeled for its active, phosphorylated form (pAMPK). In both cases, analysis of the distribution of immunopositive cells revealed a shift towards reduced intensity of staining. In contrast, NAMPT expression was upregulated in psoriatic samples in line with its pro-inflammatory role. This was again more visible with an intensity-based distribution analysis that evidenced a shift towards more intensely immunostained cell populations.ConclusionsThe present data correlate in the same samples the expression of SIRT1, pAMPK/AMPK and NAMPT in psoriasis and open the way for novel pharmacological targets in the treatment of the disease. 相似文献
15.
- DNA is the sequence that codes for proteins.
- Messenger RNA is transcribed from the DNA sequence of genes and translated into protein.
- It can be difficult to predict how a change in the DNA sequence will affect messenger RNA and protein quantity and quality.
- DNA translocation changes can cause the joining of sequences from two different genes or different parts of the same gene.
- DNA sequencing is often used clinically to predict how DNA changes might affect proteins.
- Alternatively, RNA sequencing can be used as a more direct measure of the effect of DNA changes on the protein products.
- This sequencing is important for identifying changes in cancer that may indicate response to targeted therapy, prognosis, or diagnosis.
16.
《Saudi Pharmaceutical Journal》2022,30(11):1572-1588
Non-alcoholic fatty liver disease (NAFLD) is one of the most common complications of a metabolic syndrome caused by excessive accumulation of fat in the liver. Orthosiphon stamineus also known as Orthosiphon aristatus is a medicinal plant with possible potential beneficial effects on various metabolic disorders. This study aims to investigate the in vitro inhibitory effects of O. stamineus on hepatic fat accumulation and to further use the computational systems pharmacology approach to identify the pharmacokinetic properties of the bioactive compounds of O. stamineus and to predict their molecular mechanisms against NAFLD. Methods: The effects of an ethanolic extract of O. stamineus leaves on cytotoxicity, fat accumulation and antioxidant activity were assessed using HepG2 cells. The bioactive compounds of O. stamineus were identified using LC/MS and two bioinformatics databases, namely the Traditional Chinese Medicine Integrated Database (TCMID) and the Bioinformatics Analysis Tool for the Molecular Mechanism of Traditional Chinese Medicine (BATMAN-TCM). Pathway enrichment analysis was performed on the predicted targets of the bioactive compounds to provide a systematic overview of the molecular mechanism of action, while molecular docking was used to validate the predicted targets. Results: A total of 27 bioactive compounds corresponding to 50 potential NAFLD-related targets were identified. O. stamineus exerts its anti-NAFLD effects by modulating a variety of cellular processes, including oxidative stress, mitochondrial β-oxidation, inflammatory signalling pathways, insulin signalling, and fatty acid homeostasis pathways. O. stamineus is significantly targeting many oxidative stress regulators, including JNK, mammalian target of rapamycin (mTOR), NFKB1, PPAR, and AKT1. Molecular docking analysis confirmed the expected high affinity for the potential targets, while the in vitro assay indicates the ability of O. stamineus to inhibit hepatic fat accumulation. Conclusion: Using the computational systems pharmacology approach, the potentially beneficial effect of O. stamineus in NAFLD was indicated through the combination of multiple compounds, multiple targets, and multicellular components. 相似文献
17.
《Vaccine》2022,40(6):934-944
Respiratory Syncytial Virus (RSV) remains a leading cause of severe respiratory disease for which no licensed vaccine is available. We have previously described the derivation of an RSV Fusion protein (F) stabilized in its prefusion conformation (preF) as vaccine immunogen and demonstrated superior immunogenicity in naive mice of preF versus wild type RSV F protein, both as protein and when expressed from an Ad26 vaccine vector. Here we address the question if there are qualitative differences between the two vaccine platforms for induction of protective immunity. In naïve mice, both Ad26.RSV.preF and preF protein induced humoral responses, whereas cellular responses were only elicited by Ad26.RSV.preF. In RSV pre-exposed mice, a single dose of either vaccine induced cellular responses and strong humoral responses. Ad26-induced RSV-specific cellular immune responses were detected systemically and locally in the lungs. Both vaccines showed protective efficacy in the cotton rat model, but Ad26.RSV.preF conferred protection at lower virus neutralizing titers in comparison to RSV preF protein. Factors that may contribute to the protective capacity of Ad26.RSV.preF elicited immunity are the induced IgG2a antibodies that are able to engage Fcγ receptors mediating Antibody Dependent Cellular Cytotoxicity (ADCC), and the induction of systemic and lung resident RSV specific CD8 + T cells. These data demonstrate qualitative improvement of immune responses elicited by an adenoviral vector based vaccine encoding the RSV preF antigen compared to the subunit vaccine in small animal models which may inform RSV vaccine development. 相似文献
18.
Ochratoxin A (OTA) is a mycotoxin that mainly causes nephrotoxicity. The single nephrotoxicity of OTA exposure on glomeruli or renal tubule had been well documented, however, the comparison toxicity between it is still unclear. Here, C57BL/6 mice and two types of nephrocyte were treated with concentration-gradient OTA to explore its differentiation nephrotoxicity. Results showed that OTA induced nephrotoxicity in vivo and in vitro, manifested as the deteriorative kidney function in mice and the cut-down cell viability in nephrocyte. Besides, results of murine kidney pathological section and IC50 of two types nephrocyte indicated that OTA-induced toxicity in renal tubule was higher than its in glomeruli. In addition, OTA exposure induced autophagy signaling differentiation expression. It revealed that autophagy was implicated in OTA-induced differential nephrotoxicity in glomeruli and renal tubule. Altogether, we proved that OTA induces a differentiation nephrotoxicity in glomeruli and renal tubule, and it is related to autophagy differential regulation. 相似文献
19.
目的 探讨S100蛋白(S100 protein,S100)水平联合Rotterdam计算机X线断层扫描(Computed tomography,CT)评分、格拉斯哥昏迷评分(Glasgow coma scale,GCS)在创伤性颅脑损伤(Traumatic brain injury,TBI)病情和预后不良评估中的价值。方法 回顾性分析106例TBI患者的临床资料,比较不同病情TBI患者血清S100水平、Rotterdam-CT评分,分析血清S100水平与Rotterdam-CT评分、GCS评分的相关性; 根据患者预后情况分为预后良好组和预后不良组,比较2组性别、年龄、血清S100水平、Rotterdam-CT评分、GCS评分等临床资料,多因素logistic回归分析TBI患者预后不良的相关因素; 分析S100蛋白水平、GCS评分、Rotterdam-CT评分及三者联合应用对TBI患者预后不良的预测价值。结果 轻度组、中度组、重度组血清S100水平、Rotterdam-CT评分逐渐增高(P<0.01),TBI患者血清S100水平与GCS评分(r=0.396,P=0.001)、Rotterdam-CT评分(r=0.289,P=0.002)均呈正相关; 2组血氧饱和度、GCS评分、呼吸频率、Rotterdam-CT评分、S100蛋白水平、入院时昏迷占比等指标有明显差异(P<0.05或P<0.01); 多因素logistic回归分析显示呼吸频率、血氧饱和度、入院时昏迷占比、GCS评分、Rotterdam-CT评分、S100蛋白水平均为TBI患者预后不良的相关危险因素; 受试者工作特征曲线(Receiver operator characteristic curve,ROC)显示S100蛋白水平、GCS评分、Rotterdam-CT评分对TBI患者预后不良均有一定的预测价值,三项指标联合应用曲线下面积(Area of the under curve,AUC)值大于各单项指标预测。结论 S100蛋白水平、GCS评分、Rotterdam-CT评分是TBI患者预后不良的相关危险因素,S100蛋白水平联合GCS评分、Rotterdam-CT评分在TBI患者预后不良评估中具有较高的临床价值。 相似文献
20.