呼吸道感染患儿肺炎支原体和沙眼衣原体检测结果分析

目的了解呼吸道感染患儿肺炎支原体(MP)、沙眼衣原体(CT)的检出情况。方法应用荧光定量聚合酶链反应法对1 393例呼吸道感染患儿同时进行MP、CT检测。结果 MP、CT总检出率为30.4%,其中MP为21.8%,CT为9.3%,MP合并CT为0.65%。在季节分布上,夏季MP和CT检出率最高。在年龄分布上,大于或等于3岁组的患儿MP的检出率要明显高于其他年龄组,差异有统计学意义(P<0.05);小于1个月组患儿CT检出率要高于其他组,差异有统计学意义(P<0.05)。结论夏季易检出MP和CT;3岁以上患儿较其他年龄段患儿易检出MP;新生儿较其他年龄段患儿易检出CT。荧光定量聚合酶链反应法诊断支原体、衣原体感染快速、敏感,特异性高。     

Protective Immune Responses Elicited by Fusion Protein Containing PsaA and PspA Fragments

Streptococcus pneumoniae is an important pathogen accounting for a large number of deaths worldwide. Due to drawbacks of the current polysaccharide-based vaccine, the most promising way to generate an improved vaccine may be to utilize protection-eliciting pneumococcal proteins. Pneumococcal surface adhesin A (PsaA) and pneumococcal surface protein A (PspA) are two vaccine candidates which have been evaluated against S. pneumoniae infection in animal models or human clinical trials with encouraging results. In this study, the efficacy of the fusion protein PsaA–PspA, which includes PsaA part and PspA part, in inducing immunoprotective effects against fatal pneumococcal challenge was evaluated in an animal model. PspA part of PsaA–PspA fusion protein contains both family1 N-terminal region and family 2 N-terminal clade-defining region of PspA. Immunization with the PsaA–PspA fusion protein induced high levels of antibodies against both PsaA and PspA, which could bind to intact S. pneumoniae strains bearing different PspAs. Ex vivo stimulation of splenocytes from mice immunized with PsaA–PspA induced IL-17A secretion. Mice immunized with PsaA–PspA showed reduced S. pneumoniae levels in the blood and lungs compared with the PBS group after intranasal infection. Finally, mice immunized with PsaA–PspA fusion proteins were protected against fatal challenge with pneumococcal strains expressing different PspAs regardless of the challenge route. These results support the PsaA–PspA fusion protein as a promising vaccine strategy, as demonstrated by its ability to enhance the immune response and stimulate production of high titer antibodies against S. pneumoniae strains bearing heterologous PspAs, as well as confer protection against fatal challenge with PspA family 1 and family 2 strains.     

An unreported case of Streptococcus cristatus septic arthritis of wrist in a neonate

Septic Arthritis of the wrist is rare in the paediatric population due to its extraarticular metaphysis. We report here a case of wrist septic arthritis in a neonate caused by an uncommon causative organism, Streptococcus cristatus.A 15 days old male child was referred with the complaint of swelling and decreased movement of the left wrist for 5 days. Local examination revealed warm, tender, erythematous and fluctuant swelling over the dorso-ulnar aspect of the left wrist. Ultrasonography of the affected region was suggestive of focal fluid collection in the wrist and periosteal elevation of the distal ulna. Aspiration followed by arthrotomy of the wrist joint was performed and multiple holes were made in the distal ulnar metaphysis using 0.8mm k-wire. The pus culture was positive for Streptococcus cristatus, sensitive to vancomycin, which was given for a total of 4 weeks. At one year follow up the child had a full, painless range of motion with no functional deficit. Final follow up x rays of the left wrist were normal.Streptococcus cristatus strains are described as Gram-positive, catalase-negative cocci, approximately 1 μm in diameter growing in chains and were originally isolated from the human throat and oral cavities. Its association with bone and joint infections has not been described in the literature. To our knowledge, this is the first case of isolated septic arthritis of wrist in a 15 days old child caused by Streptococcus cristatus.To conclude, wrist septic arthritis in a neonate is a rare entity. With the advanced diagnostics, species-level identification of rare organism like Streptococcus cristatus is possible along with antibiotic sensitivity for appropriate therapy. Early surgical decompression and intravenous culture-directed antibiotics are the mainstays of management.     

The role of immune correlates of protection on the pathway to licensure,policy decision and use of group B Streptococcus vaccines for maternal immunization: considerations from World Health Organization consultations

The development of a group B Streptococcus (GBS) vaccine for maternal immunization constitutes a global public health priority, to prevent GBS-associated early life invasive disease, stillbirth, premature birth, maternal sepsis, adverse neurodevelopmental consequences, and to reduce perinatal antibiotic use. Sample size requirements for the conduct of a randomized placebo-controlled trial to assess vaccine efficacy against the most relevant clinical endpoints, under conditions of appropriate ethical standards of care, constitute a significant obstacle on the pathway to vaccine availability. Alternatively, indirect evidence of protection based on immunologic data from vaccine and sero-epidemiological studies, complemented by data from opsonophagocytic in vitro assays and animal models, could be considered as pivotal data for licensure, with subsequent confirmation of effectiveness against disease outcomes in post-licensure evaluations. Based on discussions initiated by the World Health Organization we present key considerations about the potential role of correlates of protection towards an accelerated pathway for GBS vaccine licensure and wide scale use. Priority activities to support progress to regulatory and policy decision are outlined.     

口服阿奇霉素与静脉滴注红霉素治疗小儿肺炎支原体感染的疗效比较

目的比较阿奇霉素口服、红霉素静脉滴注治疗小儿肺炎支原体感染的效果。方法 185例肺炎支原体感染患儿随机分为两组,常规组92例予以红霉素静脉滴注,实验组93例予以阿奇霉素口服,比较两组的临床疗效和不良反应。结果实验组的总有效率显著高于常规组(95.70%vs. 86.96%, P<0.05), X线症状消失时间、啰音消失时间、退热时间、咳嗽消失时间以及住院时长均显著少于常规组(P<0.05),不良反应发生率显著低于常规组(6.45%vs. 18.48%, P<0.05)。结论阿奇霉素口服治疗肺炎支原体感染的患儿效果明显优于红霉素静脉滴注,用药安全性较高。     

儿童肺炎支原体感染相关喘息临床治疗研究

[摘要]目的：探讨儿童肺炎支原体（MP）感染相关喘息的临床特征及治疗，进一步为临床诊治MP感染喘息儿童提供参考。方法：选取2岁以上MP感染及非感染喘息患儿各180例，MP感染组加用阿奇霉素治疗，所有随访病例急性发作时选用支气管扩张剂及布地奈德雾化治疗。两组病例按选用长期控制的药物不同分为三组（n=60）：即孟鲁司特组、孟鲁司特组+ICS组、对照组，比较治疗前和治疗6月后的临床指标。结果：（1）MP感染患儿：孟鲁司特组与对照组治疗后FeNO和EOS检测阳性病例数比较差异有统计学意义（P<0.05）；孟鲁司特+ICS组与对照组治疗后急性发作、肺部体征阳性例数、FeNO、IgE、EOS、过敏原、肺功能阳性例数比较差异有统计学意义（P<0.05）；孟鲁司特+ICS组与孟鲁司特组治疗后急性发作、肺部体征、FeNO检测阳性病例数比较差异有统计学意义（P<0.05）。（2）非MP感染患儿：孟鲁司特组与对照组治疗后肺功能检测阳性病例数比较差异有统计学意义（P<0.05）；孟鲁司特+ICS组与对照组治疗后急性发作、肺部体征阳性例数、FeNO、IgE、EOS、肺功能阳性例数比较差异有统计学意义（P<0.05）；孟鲁司特+ICS组与孟鲁司特组治疗后肺部体征阳性例数比较差异有统计学意义（P<0.05）。结论：目前常用的孟鲁司特或孟鲁司特+ICS的治疗方案对MP感染诱发喘息的治疗是有效的，孟鲁司特+ICS的联合治疗对MP感染后诱发喘息患儿治疗效果优于单用孟鲁司特。今后尚需进一步扩大样本量进行临床长期随访研究，以期能进一步明确MP感染导致儿童哮喘的发生机制以及对哮喘儿童的长期影响。     

Cas9 function and host genome sampling in Type II-A CRISPR–Cas adaptation

To acquire the ability to recognize and destroy virus and plasmid invaders, prokaryotic CRISPR–Cas systems capture fragments of DNA within the host CRISPR locus. Our results indicate that the process of adaptation by a Type II-A CRISPR–Cas system in Streptococcus thermophilus requires Cas1, Cas2, and Csn2. Surprisingly, we found that Cas9, previously identified as the nuclease responsible for ultimate invader destruction, is also essential for adaptation. Cas9 nuclease activity is dispensable for adaptation. In addition, our studies revealed extensive, unbiased acquisition of the self-targeting host genome sequence by the CRISPR–Cas system that is masked in the presence of active target destruction.     

中药对肺炎克雷伯菌的抗菌作用的研究进展

肺炎克雷伯菌,因其耐药谱广,耐药率高,其治疗问题已成为世界性难题。中药具有低耐药性、多作用靶位的广谱抗菌效果,因此进行中药治疗或与西药联合治疗是一种对抗多重耐药菌的新型手段。检索近年来中国知网、万方全文和Pubmed等数据库的文献,从肺炎克雷伯的耐药机制和中药抗肺炎克雷伯菌耐药性作用等研究成果,阐述中药复合制剂以及其有效成分在临床上用于治疗肺炎克雷伯菌引起的感染的疗效及作用机制。中药可以通过抑制β-内酰胺酶、对抗生物膜的形成、对抗内毒素的作用以及抑制外排泵等起到抗肺炎克雷伯菌作用。通过对中药的抗菌作用机制进行深入研究,有助于准确全面地评价药效,为今后抗生素的合理选择提供依据。     

肺炎衣原体感染与哮喘急性发作的相关性研究

目的探讨肺炎衣原体(CP)感染与哮喘急性发作相关性,以期提高临床诊治水平。方法选取2011年3月-2013年3月47例哮喘急性发作患者为哮喘急性发作组,另外选取同时期哮喘缓解期患者45例为哮喘缓解组和43名健康体检人员作为对照组,运用微量免疫荧光法测定血清CP特异性抗体IgA、IgM和IgG,观察3组在感染相关指标的变化。结果哮喘急性发作组和哮喘缓解组的CP-IgA、CP-IgG、CP-IgM阳性率相近,健康对照组与以上两组比较,差异有统计学意义(P<0.05),3组CP-IgA、CP-IgG、CP-IgM滴度两两比较,差异均有统计学意义(P<0.05);CP感染率哮喘急性发作组66.0%、哮喘缓解组68.9%、健康对照组仅为9.3%,哮喘急性发作组以急性感染为主,而哮喘缓解组患者中则有51.1%以慢性感染为主。结论急性CP感染是哮喘急性发作重要诱因,而慢性CP感染是支气管哮喘急性发作期和缓解期重要影响因素,参与了支气管哮喘发病机制和病理过程。     

Epidemiology of Serotype 1 Invasive Pneumococcal Disease,South Africa, 2003–2013

In South Africa, 7-valent pneumococcal conjugate vaccine (PCV) was introduced in April 2009 and replaced with 13-valent PCV in April 2011. We describe the epidemiology of serotype 1 Streptococcus pneumoniae disease during the pre- and post-PCV eras (2003–2013). Using laboratory-based invasive pneumococcal disease (IPD) surveillance, we calculated annual incidences, identified IPD clusters, and determined serotype 1–associated factors. Of 46,483 IPD cases, 4,544 (10%) were caused by serotype 1. Two clusters of serotype 1 infection were detected during 2003–2004 and 2008–2012, but incidence decreased after 2011. Among children <5 years of age, those who had non–serotype 1 IPD had shorter hospital stays, fewer cases of penicillin-nonsusceptible disease, and lower HIV prevalence and in-hospital death rates than did those with serotype 1 IPD; similar factors were noted for older patients. Serotype 1 IPD had distinctive clinical features in South Africa, and annual incidences fluctuated, with decreases noted after the introduction of PCV13.