六安市手足口病1311例临床分析

目的：探讨手足口病的临床特征、流行病学特点及主要预防治疗方法。方法：回顾性分析六安市人民医院儿科2008年5月-2008年10月在手足口病防治期间共收治的手足口病患儿1311例的流行病学特点、临床表现、实验室检查及治疗效果。结果：1311例手足口患者并发神经系统损害56例,并发心肌损害466例,肝功能损害2例,并发肺炎2例。治愈1291例,好转20例,无死亡病例。结论：手足口病一般病情较轻,重症患儿多见于3岁以下婴幼儿,早期发现并给予大剂量甲强龙及丙球治疗效果良好。     

广西壮族自治区1996年脊髓灰质炎疫情分析

广西壮族自治区１９９６年临床诊断脊髓灰质炎（脊灰）６例，其中因发病６０天后仍残留麻痹诊断５例，失访诊断１例。６例均为２岁以下儿童；未服脊灰疫苗者２例，免疫１～２次者３例。临床诊断６例脊灰均采集了粪便标本，其中病毒分离阴性１例，脊灰Ⅰ、Ⅱ、Ⅲ型病毒各１例（经国家脊灰实验室鉴定均为疫苗株病毒），非脊灰肠道病毒２例。１９９３～１９９６年未发现脊灰野病毒引起的麻痹病例。     

Differences in replication capacity between enterovirus 71 isolates obtained from patients with encephalitis and those obtained from patients with herpangina in Taiwan

The cellular-tropism and biological characteristics of enterovirus 71 (EV71) isolates in Taiwan (TW) were studied. Growth curve experiments were conducted using cell lines that were possibly exhibited pathogenesis, and RT-PCR and sequencing tests were undertaken to amplify the 5' non-coding region (5'-NCR). The encephalitis isolate EV71 TW98NTU2078 was PBMC-tropic, temperature-resistant (Tr) at 40 degrees C, and easier to replicate in HTB-14 (astrocytoma) than the herpangina isolate EV71 TW98NTU1186 (The viral yields were 100-fold higher than those of the herpangina isolate EV71 TW98NTU1186 at 96 hr post infection.). The herpangina isolate EV71 TW98NTU1186 was non-PBMC-tropic, and temperature-sensitive (Ts) at 40 degrees C. The replication of EV71 TW98NTU1186 in HTB-14 was lower. No EV71 isolate infected HTB-37 (human colon adenocarcinoma cells). The encephalitis EV71 isolate exhibited better replication and transmission in PBMCs and astrocytes than did the EV71 isolate without CNS involvement.     

Fibroblast-stimulating lipopeptide-1 as a potential mucosal adjuvant enhances mucosal and systemic immune responses to enterovirus 71 vaccine

To prevent viral infection at the site of entry, mucosal vaccines are potent tools for inducing IgA secretion for defense. Because Toll-like receptor (TLR) ligands serve as strong adjuvants, two ligands that mimic the structure of mycoplasmal and bacterial lipopeptides represent interesting vaccine candidates. Pam3CSK4, a synthetic triacylated lipopeptide, interacts with TLR2/1. Because fibroblast-stimulating lipopeptide-1 (FSL-1), a synthetic diacylated lipopeptide, is recognized by TLR2/6, we targeted the potential immuno-inducibility of Pam3CSK4 and FSL-1 as adjuvants of an enterovirus 71 (EV71) mucosal vaccine. Naïve BALB/c mice were used for intranasal immunization three times over a 3-week interval, with results showing that EV71-specific IgG and IgA in serum, nasal washes, bronchoalveolar lavage fluid, and feces from the EV71 + FSL-1 group were significantly higher than levels observed in mice treated with EV71 + Pam3CSK4, EV71 alone, or the control group treated with phosphate-buffered saline. Furthermore, we observed more EV71-specific IgG and IgA-producing cells in treatments using EV71 formulated with FSL-1. Additionally, T cell-proliferative responses and interferon-γ and interleukin-17 secretion were significantly increased when inactivated EV71 was formulated using FSL-1. Moreover, serum from immunized mice was capable of neutralizing the infectivity of EV71 (C2 genotype) and was able to cross-neutralize the B4 and B5 genotypes of EV71. Our data suggested that FSL-1 could be used as an efficient adjuvant for intranasal EV71-vaccine immunization.     

Virus inactivation of plasma-derived proteins by pasteurization in the presence of guanidine hydrochloride

BACKGROUND: Viruses, among them parvovirus B19 and other small, nonenveloped viruses, may be present in human blood and may contaminate plasma-derived therapeutics. Efficient inactivation or removal of such viruses, especially parvoviruses, represents a current problem and corresponding technologies are under investigation. In this report, such a technology is described. STUDY DESIGN AND METHODS: A recently developed pasteurization of human apolipoprotein A-I (apoA-I), which is performed at 60 degrees C for 10 hours in the presence of guanidine hydrochloride (GdnHCl), was validated by using a series of model viruses, including members of the families parvoviridae and picornaviridae. The model viruses were spiked into the apoA-I- and GdnHCl-containing solutions, and virus inactivation was evaluated by infectivity assays in cell cultures. The mechanism of virus inactivation was studied by virus sedimentation analysis using the picornavirus model. RESULTS: All viruses tested were inactivated to levels below the limit of detection, although different inactivation kinetics were obtained for the different viruses. The mechanism of virus inactivation by this pasteurization was disassembly of the virus particles into single proteins or small noninfectious viral subunits. CONCLUSION: The pasteurization validated in this report has the potential to inactivate a wide range of transfusion-relevant viruses including parvoviruses and picornaviruses.     

Nucleobase but not Sugar Fidelity is Maintained in the Sabin I RNA-Dependent RNA Polymerase

The Sabin I poliovirus live, attenuated vaccine strain encodes for four amino acid changes (i.e., D53N, Y73H, K250E, and T362I) in the RNA-dependent RNA polymerase (RdRp). We have previously shown that the T362I substitution leads to a lower fidelity RdRp, and viruses encoding this variant are attenuated in a mouse model of poliovirus. Given these results, it was surprising that the nucleotide incorporation rate and nucleobase fidelity of the Sabin I RdRp is similar to that of wild-type enzyme, although the Sabin I RdRp is less selective against nucleotides with modified sugar groups. We suggest that the other Sabin amino acid changes (i.e., D53N, Y73H, K250E) help to re-establish nucleotide incorporation rates and nucleotide discrimination near wild-type levels, which may be a requirement for the propagation of the virus and its efficacy as a vaccine strain. These results also suggest that the nucleobase fidelity of the Sabin I RdRp likely does not contribute to viral attenuation.     

Glucose-6-Phosphate Dehydrogenase Enhances Antiviral Response through Downregulation of NADPH Sensor HSCARG and Upregulation of NF-κB Signaling

Glucose-6-phosphate dehydrogenase (G6PD)-deficient cells are highly susceptible to viral infection. This study examined the mechanism underlying this phenomenon by measuring the expression of antiviral genes—tumor necrosis factor alpha (TNF-α) and GTPase myxovirus resistance 1 (MX1)—in G6PD-knockdown cells upon human coronavirus 229E (HCoV-229E) and enterovirus 71 (EV71) infection. Molecular analysis revealed that the promoter activities of TNF-α and MX1 were downregulated in G6PD-knockdown cells, and that the IκB degradation and DNA binding activity of NF-κB were decreased. The HSCARG protein, a nicotinamide adenine dinucleotide phosphate (NADPH) sensor and negative regulator of NF-κB, was upregulated in G6PD-knockdown cells with decreased NADPH/NADP⁺ ratio. Treatment of G6PD-knockdown cells with siRNA against HSCARG enhanced the DNA binding activity of NF-κB and the expression of TNF-α and MX1, but suppressed the expression of viral genes; however, the overexpression of HSCARG inhibited the antiviral response. Exogenous G6PD or IDH1 expression inhibited the expression of HSCARG, resulting in increased expression of TNF-α and MX1 and reduced viral gene expression upon virus infection. Our findings suggest that the increased susceptibility of the G6PD-knockdown cells to viral infection was due to impaired NF-κB signaling and antiviral response mediated by HSCARG.     

Enterovirus D68 detection in respiratory specimens: Association with severe disease

Molecular techniques increased the number of documented respiratory infections. In a substantial number of cases the causative agent remains undetected. Since August 2014, an increase in Enterovirus(EV)‐D68 infections was reported. We aimed to investigate epidemiology and clinical relevance of EV‐D68. From June to December 2014 and from September to December 2015, 803 and 847 respiratory specimens, respectively, were tested for respiratory viruses with a multiplex RT‐PCR. This multiplex RT‐PCR does not detect EV‐D68. Therefore, 457 (2014) and 343 (2015) specimens with negative results were submitted to an EV‐specific‐RT‐PCR. EV‐positive specimens were tested with an EV‐D68‐specific‐RT‐PCR and genotyped. Eleven specimens of 2014 tested positive in the EV‐specific‐RT‐PCR and of these seven were positive in the EV‐D68‐specific‐RT‐PCR. Typing confirmed these as EV‐D68. Median age of EV‐D68‐positive patients was 3 years (1 month‐91 years). Common symptoms included fever (n = 6, 86%), respiratory distress (n = 5, 71%), and cough (n = 4, 57%). All EV‐D68‐positive patients were admitted to hospital, 4 (57%) were admitted to intensive care units and 6 (86%) received oxygen. One patient suffered from acute flaccid paralysis. Seven specimens of 2015 were positive in the EV‐specific‐RT‐PCR but negative in the EV‐D68‐specific‐RT‐PCR. In conclusion, use of an EV‐specific‐RT‐PCR allowed us to detect EV‐D68 circulation in autumn 2014 that was not detected by the multiplex RT‐PCR and was associated with severe disease.