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21.
On 31 December 2019, the Wuhan Municipal Committee of Health and Healthcare (Hubei Province, China) reported that there were 27 cases of pneumonia of unknown origin with symptoms starting on the 8 December. There were 7 serious cases with common exposure in market with shellfish, fish, and live animals, in the city of Wuhan. On 7 January 2020, the Chinese authorities identified that the agent causing the outbreak was a new type of virus of the Coronaviridae family, temporarily called «new coronavirus», 2019-nCoV. On January 30th, 2020, the World Health Organisation (WHO) declared the outbreak an International Emergency. On 11 February 2020 the WHO assigned it the name of SARS-CoV2 and COVID-19 (SARS-CoV2 and COVID-19).The Ministry of Health summoned the Specialties Societies to prepare a clinical protocol for the management of COVID-19. The Spanish Paediatric Association appointed a Working Group of the Societies of Paediatric Infectious Diseases and Paediatric Intensive Care to prepare the present recommendations with the evidence available at the time of preparing them.  相似文献   
22.
《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   
23.
彭瑶  胡立  蒲虹 《中国热带医学》2019,19(7):696-699
目的 分析HBV患者YKL-40、CA19-9、GP73水平差异及与患者病情轻重程度的相关性,探讨HBV患者病情的判定指标。方法 选取2015年5月—2018年5月收治的100例HBV患者,其中慢性HBV感染组40例、慢性乙型肝炎组36例、HBV相关肝硬化组24例,同期选择我院健康体检的健康者50例作为健康对照组;检测患者血中YKL-40、CA19-9、GP73水平;分析HBV感染患者血清YKL-40、CA19-9、GP73水平与病情轻重程度的相关性。结果 慢性HBV感染、慢性乙型肝炎及HBV相关肝硬化患者血中YKL-40水平分别为(36.38±4.19)ng/mL 、(49.02±4.32)ng/mL、(65.14±5.21)ng/mL ,CA19-9分别为(12.03±1.03)KU/L、(13.84±0.98)KU/L、(16.94±0.81)KU/L,GP73分别为(47.22±5.38)ng/mL 、(98.53±10.24)ng/mL 、(229.85±12.19)ng/mL,均明显高于对照组的(28.19±3.27)ng/mL 、(7.34±0.92)KU/L 、(30.93±3.89)ng/mL,均P=0.000 0。随着慢性HBV感染者、慢性乙型肝炎患者和不同HBV相关肝硬化患者肝脏炎症及纤维化程度加重,患者血中YKL-40、CA19-9和GP73也随之显著增加,均P=0.000 0;YKL-40、CA19-9和GP73均是影响HBV感染患者体内炎症坏死及肝脏纤维化的独立性影响因素,差异有统计学意义(P<0.05)。结论 HBV感染患者血清中YKL-40、CA19-9、GP73水平是HBV感染患者病情轻重程度的独立性影响因素。  相似文献   
24.
Tuberculosis (TB) remains one of a major health problem worldwide. Tuberculosis vaccine research has made an extraordinary progress over the past few years. However, there is still no replacement for the Bacillus Calmette‐Guérin vaccine, the only TB vaccine licensed for human use. Therefore, the discovery and development of new TB vaccines remains a priority. This article discusses current strategies used to diversify TB vaccines and includes discussion of the status of efforts to improve protection against Mycobacterium tuberculosis (M tb) infection or TB disease by developing new and safe TB vaccines. This article also highlights the current research efforts in immune‐enhancing approaches to improve vaccination efficacy. The development of more effective TB vaccines might have significant impact on global TB control.  相似文献   
25.
关节假体周围感染(periprosthetic joint infection,PJI)是人工关节置换术后可能发生的一种严重并发症,其导致的严重后果,无论对于医生还是患者来说,都很难接受。目前,由于多种不确定因素的存在,PJI诊断的准确性较低。传统的血清学检查、影像学检查有一定的价值,但是易受全身情况的影响,导致特异性不高。为了正确诊断关节假体周围感染,不同学科的研究人员采用各种不同的方法进行了大量的诊断研究,并取得了丰富的成果。近年来,关节滑液炎性标志物检测、分子生物学方法等被研究证实具有较高的敏感性和特异性。因此,关节滑液CRP、-防御素、白细胞酯酶、PCR技术等被广泛研究,期望能从中找到诊断关节假体周围感染的特异性指标,提高临床诊断的准确性。  相似文献   
26.
27.
《Immunity》2022,55(7):1316-1326.e4
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28.
Bacterial keratitis continues to be one of the leading causes of corneal blindness in the developed as well as the developing world, despite swift progress since the dawn of the “anti-biotic era”. Although, we have expeditiously developed our understanding about the different causative organisms and associated pathology leading to keratitis, extensive gaps in knowledge continue to dampen the efforts required for early and accurate diagnosis, and management in these patients, resulting in poor clinical outcomes. The ability of the causative bacteria to subdue the therapeutic challenge stems from their large genome encoding complex regulatory networks, variety of unique virulence factors, and rapid secretion of tissue damaging proteases and toxins.In this review article, we provide an overview of the established diagnostic techniques and therapeutics for keratitis caused by various bacteria. We extensively report the recent in-roads through novel tools for accurately diagnosing mono- and poly-bacterial corneal infections. Furthermore, we outline the recent progress by our groups and others in understanding the sub-cellular genomic changes that lead to antibiotic resistance in these organisms. Finally, we discuss in detail, the novel therapies and drug delivery systems in development for the efficacious management of bacterial keratitis.  相似文献   
29.
30.
《Vaccine》2016,34(48):5912-5915
Immunochromatography (ICG) is highly used in clinical settings for rotavirus (RV) diagnosis. The specificity of the tests differs by brand type and is not 100%, therefore its use when the prevalence of the disease is low (i.e. in vaccinated children) may result in a proportion of false positive diagnoses.In some areas, vaccine effectiveness studies or surveillance is done using ICG. Our objective was to estimate the validity of ICG test in vaccinated children, and estimate the number of false positive results in the Valencian Region of Spain, where all RV infections are diagnosed using ICG and are not confirmed by PCR.Population based registries were used to identify all results from the RV antigen tests performed between January 2008 and June 2012 in children under 37 months. Hospitalization and vaccination status of the patients were obtained by linking different databases through a unique identification number. The Positive Predictive Value of the ICG test depending on the vaccination status of the child, hospitalization and the rotavirus season was estimated by a Bayesian model of latent classes.Of the 48,833 tests with valid results, 9429 were done in vaccinated children, and of those 3963 (42%) during the rotavirus season. The prevalence of positive results in vaccinated varied from 2.9 to 21.4% of the tests depending on the hospitalization and seasonality. The estimated PPV also varied from 27.1 to 84.6% when stratified by these two parameters. Globally it is calculated that approximately 267 out of the 520 (51.3%) positives in vaccinated children were false positive tests.The large percentage of false positives, due to an excessive number of tests in vaccinated and out of the RV season, if interpreted as vaccine failures, can cause a loss of confidence in the vaccine and lower the estimates of vaccine effectiveness.  相似文献   
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