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71.
Bacterial conjugate vaccines are based on the principle of coupling immunogenic bacterial capsular polysaccharides to a carrier protein to facilitate the induction of memory T-cell responses. Following the success of Haemophilus influenzae type b conjugate vaccines in the 1980s, conjugate vaccines for Streptococcus pneumoniae and Neisseria meningitidis infections were developed and proven to be effective in protecting children against invasive disease. In this review, the use of conjugate vaccines in human newborns is discussed. Neonatal Haemophilus influenzae type b and pneumococcal conjugate vaccination schedules have been trialed and proven to be safe, with the majority of studies demonstrating no evidence for the induction of immune tolerance. Whether their neonatal administration also results in an earlier induction of clinical protection in the first 2–3 critical months of life is still to be demonstrated.  相似文献   
72.
A three-year-old boy presented with community-acquired pneumonia complicated by empyema. Streptococcus pyogenes (group A streptococcus) was identified on culture of the pleural fluid. The patient improved with antibiotic therapy and drainage of the empyema.During his convalescence, the patient developed persistent fever, lethargy and anorexia. His inflammatory markers were elevated, and repeat cultures were negative. Although the patient had none of the classical mucocutaneous features of Kawasaki disease, an echocardiogram was performed, which revealed coronary artery dilation.The patient was diagnosed with incomplete Kawasaki disease and treated with intravenous immunoglobulin and high-dose acetylsalicylic acid. The fever subsided within 48 h.To the authors’ knowledge, the present report is the first report of Kawasaki disease associated with complicated S pyogenes pneumonia. It emphasizes the importance of considering incomplete Kawasaki disease among children with persistent fever, the role of echocardiography in diagnosis, and the potential link between Kawasaki disease and superantigen-producing organisms such as S pyogenes.  相似文献   
73.
目的 Dpr蛋白是与细菌毒力密切相关的铁离子结合蛋白,从Dpr蛋白潜在的相互作用蛋白网络出发,通过生物信息学手段分析这些蛋白发挥的功能以及参与的生物过程,揭示Dpr 蛋白在化脓链球菌(Streptococcus pyogenes)中发挥作用的新机制。方法 表达和纯化融合蛋白(GST-Dpr);通过 GST-Pull down 和质谱联用的方式,筛选化脓链球菌中与 Dpr 蛋白相互作用的蛋白。结果 三次独立重复实验共同鉴定到 26 个相互作用蛋白;基于String分析构建各蛋白间的相互作用网络发现,这些相互作用蛋白中有 15 个蛋白与 Dpr 存在直接或间接的联系;利用生物信息学手段分析这些相互作用蛋白的分子功能以及可能参与的生物学途径,发现它们大多能够结合金属离子,主要参与碳代谢、丙酮酸代谢、糖代谢以及糖异生等生物过程。结论 Dpr蛋白可能通过与本研究中鉴定的GAPDH、AccD、Eno、RpsB 和 Fus等蛋白相互作用来共同完成相关的生物学功能。通过建立的Dpr蛋白相互作用蛋白网络,为全面阐述 Dpr 蛋白在细菌定植和毒力方面的功能提供了重要的理论基础和新思路。  相似文献   
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Kahlke V  Fischer A  Schröder J 《Infection》2000,28(2):114-115
Summary A peritonitis cause by an ascending infection is a rare complication postpartum. A 37-year-old women presented with a secondary peritonitis due to Streptococcus pneumoniae. The patient had given birth to a healthy boy 4 weeks before and showed no symptoms of a bronchitis on admission. A operation was performed after the patient developed an acute abdomen, showing a diffuse peritonitis. High vaginal swabs and blood cultures taken on admission were positive for S. pneumoniae as well as the specimen taken during the operation. Thus we concluded that this was a case of an ascending infection. After antibiotic therapy with penicillin the patient could be discharged 8 days after the operation. Received: July 6, 1999 · Accepted: January 5, 2000  相似文献   
77.
目的 研究白芍粗提物及其主要成分芍药苷对变异链球菌的作用。 方法 采用醇提法制取白芍粗提物,通过高效液相色谱法测定白芍粗提物的主要活性成分,分别观察白芍粗提物及其主要成分芍药苷在不同药物浓度下对变异链球菌的粘附、产酸、合成水不溶性胞外多糖以及葡聚糖转移酶(GTF)比活力等方面的影响。 结果 白芍粗提物及芍药苷对变异链球菌的体外生长最小抑菌浓度(MIC)分别为3.130和1.770 mg/mL,当两者的浓度分别为≥1.565和≥0.885 mg/mL时,有明显的抑制变异链球菌粘附、合成水不溶性胞外多糖和GTF比活力的作用(P<0.05); 当白芍粗提物浓度为3.130 mg/mL时,有明显的抑制变异链球菌产酸的作用(P<0.05),而不同浓度的芍药苷对变异链球菌产酸均无影响(P>0.05)。不同浓度白芍粗提物组和芍药苷组的水不溶性胞外多糖含量和GTF比活力之间均呈正向直线相关。 结论 白芍粗提物可抑制变异链球菌的粘附、产酸、合成水不溶性胞外多糖和GTF活性,其主要活性成分芍药苷可抑制变异链球菌的粘附、合成水不溶性胞外多糖和GTF活性,但不影响变异链球菌的产酸活动。  相似文献   
78.
Introduction: Central nervous system infection continues to be an important cause of mortality and morbidity worldwide. Our incomplete knowledge on the pathogenesis of how meningitis-causing pathogens cause CNS infection and emergence of antimicrobial resistance has contributed to the mortality and morbidity. An early empiric antibiotic treatment is critical for the management of patients with bacterial meningitis, but early recognition of bacterial meningitis continues to be a challenge.

Areas covered: This review gives an overview on current therapeutic strategies for CNS infection with a focus on recent literature since 2010 on bacterial meningitis. Bacterial meningitis is a medical emergency, requiring early recognition and treatment. The selection of appropriate empiric antimicrobial regimen, after incorporating the epidemiology of bacterial meningitis, impact of vaccination, emergence of antimicrobial-resistant bacteria, role of adjunctive therapy and the current knowledge on the pathogenesis of meningitis and associated neuronal injury are covered.

Expert opinion: Prompt treatment of bacterial meningitis with an appropriate antibiotic is essential. Optimal antimicrobial treatment of bacterial meningitis requires bactericidal agents able to penetrate the blood–brain barrier, with efficacy in cerebrospinal fluid. Emergence of CNS-infecting pathogens with resistance to conventional antibiotics has been increasingly recognized, but development of new antibiotics has been limited. More complete understanding of the microbial and host factors that are involved in the pathogenesis of bacterial meningitis and associated neurologic sequelae is likely to help in developing new strategies for the prevention and therapy of bacterial meningitis.  相似文献   

79.
Differentiated HL-60 is an effector cell widely used for the opsonophagocytic-killing assay (OPKA) to measure efficacy of pneumococcal vaccines. We investigated the correlation between phenotypic expression of immunoreceptors and phagocytic ability of HL-60 cells differentiated with N,N-dimethylformamide (DMF), all-trans retinoic acid (ATRA), or 1α, 25-dihydroxyvitamin D3 (VitD3) for 5 days. Phenotypic change was examined by flow cytometry with specific antibodies to CD11c, CD14, CD18, CD32, and CD64. Apoptosis was determined by flow cytometry using 7-aminoactinomycin D. Function was evaluated by a standard OPKA against serotype 19F and chemiluminescence-based respiratory burst assay. The expression of CD11c and CD14 gradually increased upon exposure to all three agents, while CD14 expression increased abruptly after VitD3. The expression of CD18, CD32, and CD64 increased during differentiation with all three agents. Apoptosis remained less than 10% until day 3 but increased after differentiation by DMF or ATRA. Differentiation with ATRA or VitD3 increased the respiratory burst after day 4. DMF differentiation showed a high OPKA titer at day 1 which sustained thereafter while ATRA or VitD3-differentiated cells gradually increased. Pearson analysis between the phenotypic changes and OPKA titers suggests that CD11c might be a useful differentiation marker for HL-60 cells for use in pneumococcal OPKA.

Graphical Abstract

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80.
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