Improved outcome of chronic Pseudomonas aeruginosa lung infection is associated with induction of a Th1-dominated cytokine response

Repeated challenge with antigen is involved in the pathogenesis of a variety of pulmonary diseases. Patients with cystic fibrosis (CF) experience recurrent pulmonary colonization with Pseudomonas aeruginosa before establishment of chronic lung infection. To mimic recurrent lung infections in CF patients, the lungs of susceptible BALB/c mice were re-infected with P. aeruginosa 14 days after the initial infection. Singly-infected BALB/c mice, as well as non-infected mice, were used as controls. Decreased mortality and milder lung inflammation in re-infected BALB/c mice, as well as a tendency for improved clearance of bacteria, was observed when compared with singly-infected mice. The improved outcome in re-infected mice correlated with changes in CD4 cell numbers. Surface expression of LFA-1 on pulmonary CD4 cells was increased in re-infected compared with singly-infected mice. Moreover, resistance to re-infection was paralleled by a shift towards a Th1-dominated response and increased IL-12 production. No significant increase in serum IgG was observed in the re-infected mice. In conclusion, these results indicate a protective role for a Th1-dominated response, independent of antibody production, in chronic P. aeruginosa lung infection in CF.     

临床分离4364株细菌的分布特征和耐药性变迁分析

目的了解2003—2005年分离的4364株细菌的分布特征及耐药性变迁，为合理使用抗菌药物提供依据。方法大多数分离细菌的鉴定和药敏试验利用BD Phoenix仪，少数利用手工鉴定和K-B法药敏试验。数据分析用WHONET5．0软件。结果葡萄球菌对万古霉素和替考拉宁的敏感率一直为100％，对其他抗菌药物的耐药率大多逐年上升，甲氧西林耐药率也逐年上升，金黄色葡萄球菌从40．8％上升到61．6％，表皮葡萄球菌从69．7％上升到79．8％。G^-杆菌合计，大多数抗菌药物的耐药率逐年升高，耐药率一直低于30％的为美洛培南、亚安培南、头孢哌酮／舒巴坦、哌拉西林-他唑巴坦和头孢他啶。大肠埃希菌和肺炎克雷伯菌体外产ESBLs的检出率一直居高不下，为29．5％～45．5％。结论本院肠杆菌科产ESBLs比例、葡萄球菌甲氧西林耐药率和非发酵菌碳青霉烯类耐药率均较高，应加强抗菌药物的合理使用和采取有效的隔离措施以降低耐药率及多重耐药菌的扩散。     

Pneumonien bei akuten Leukämien

Summary Acute leukaemia was complicated by pneumonia in 38 (34.8%) of 109 patients treated between 1979 and 1983; in 39.5% of the patients pneumonia occurred more than once. In 23 patients (60.5%) pneumonia occurred during cytostatic therapy, and 25 patients (65.8%) had less than 1000 mm² granulocytes. Antibiotic therapy had no or only little effect in 70%. A total of 21 patients (55.3%) died of pneumonia. In 15 patients a direct relationship could be seen between pneumonia and the bacterial spectrum in the sputum. A prevalence of gram-negative bacteria was found (24 of 40 bacteria isolated, especially Enterobacteriaceae (19). Fungi were cultivated in 10 cases. Each of the typical pneumonia bacteria was only seen once respectively. It is most important that therapy begin immediately, even before the bacteria have been identified. Only then is there hope that the survival time of patients with acute leukaemia can be influenced.

     

革兰阴性杆菌去阻遏持续高产AmpC酶检测及耐药性分析

目的:了解近期临床分离的30株革兰氏阴性杆菌去阻遏持续高产AmpC酶情况及对15种抗菌药物的耐药性,并对三种AmpC酶检测方法进行比较,为临床提供常规检测和用药的参考。方法:用头孢西丁药敏法、表型筛选法和三维实验法分别检测AmpC酶,用纸片扩散法进行体外药敏实验。结果:头孢西丁药敏法、表型筛选法和三维实验法的AmpC酶检出率分别为56.7%、13.3%、10.0%,头孢西丁药敏实验与三维实验相比,存在较高假阳性率82.4%,表型筛选法与三维实验符合率达96.7%;17株耐头孢西丁菌株的药敏实验显示出严重的多重耐药,对青霉素类及加β-内酰胺酶抑制剂克拉维酸的复合药物、氨基糖苷类均呈高比例耐药,对加β-内酰胺酶抑制剂舒巴坦和他唑巴坦的头孢菌素类较为敏感,而对亚安培南和头孢肶肟的敏感率达100%。结论:表型筛选法操作简单省时,且准确率高,适合临床推广使用;治疗产AmpC酶菌感染以亚安培南和第四代头孢菌素头孢肶肟较优。     

基因芯片技术检测环境中常见致病菌的初步研究

目的：为了快速，准确地检测环境中存在的致病菌，建立一种采用基因芯片技术对环境中常见致病检测和鉴定的实验方法。方法：采用合成后点样的方法把自行设计合成的一系列寡核苷酸探针固定在经过醛基化修饰的显微镜载玻片上，制成用于致病菌检测的基因芯片。结果：在相同的条件下，扩增了涉及12个菌属的151株细菌的165rDNA基因片段并与基因芯片杂交，经Scan-Array3000芯片阅读仪扫描得到特异性的交杂图，归纳这些杂交图，得到一套属（种）特异的典型杂交图谱。待检的样品菌与基因芯片进行杂交，得到的杂交结果与典型图谱比对即可判断出样品的种类。用这样的方法对从实际样品中分离的细菌进行检测，准确率表达了96．2％（25／26）。结论：该项技术的建立为今后更大规模的检测研究奠定了基础，可以推广应用于感染性疾病诊断，环境监测，食品卫生监督，商品检验检疫等领域。     

Segmentation of Bacteria Image Based on Level Set Method

In biology ferment engineering, accurate statistics of the quantity of bacteria is one of the most important subjects. In this paper, the quantity of bacteria which was observed traditionally manuauy can be detected automatically. Image acquisition and processing system is designed to accomplish image preprocessing, image segmentation and statistics of the quantity of bacteria. Segmentation of bacteria images is successfully realized by means of a region-based level set method and then the quantity of bacteria is computed precisely, which plays an important role in optimizing the growth conditions of bacteria.     

Comparative in vitro activity of BAY 12-8039 and five other antimicrobial agents against anaerobic bacteria

The in vitro activity of BAY 12-8039 against 360 anaerobic clinical isolates was determined by the agar dilution method and compared to that of five other antimicrobial agents. BAY 12-8039 and imipenem were the most active agents tested. The following MIC90 values were determined for BAY 12-8039Peptostreptococcus spp. (50 isolates), 1 mg/l;Propionibacterium acnes (30 isolates), 0.25 mg/l;Clostridium perfringens (30 isolates), 0.5 mg/l;Clostridium difficile (50 isolates), 2 mg/l;Bacteroides fragilis (50 isolates), 1 mg/l;non- fragilis Bacteroides, Porphyromonas, andPrevotella spp. (100 isolates), 2 mg/l; andFusobacterium spp. (50 isolates), 0.25 mg/l. The results of the present study show that BAY 12-8039 may be useful in the treatment and prophylaxis of anaerobic infections.     

Production of IL-12, IL-23 and IL-27p28 by bone marrow-derived conventional dendritic cells rather than macrophages after LPS/TLR4-dependent induction by Salmonella Enteritidis

Induction of the interleukin-12 (IL-12) cytokine family comprising IL-12, IL-23, IL-27, and IL-12p40 by intracellular pathogens is required for orchestration of cell-mediated immune responses. Macrophages (MΦ) have been shown to be a source of IL-12 following TLR4-dependent activation by Salmonella (S.). In this study another antigen-presenting cell type, the conventional dendritic cell (cDC), was analyzed and its cytokine responses compared with those of MΦ. We generated bone marrow-derived conventional dendritic cells (BMDC) and macrophages (BMMΦ) by incubating murine bone marrow cells with supernatants containing granulocyte/macrophage colony-stimulating factor (GM-CSF) or macrophage colony-stimulating factor (M-CSF), respectively. Stimulation of BMDC and BMMΦ with S. enterica serovar Enteritidis (SE) or LPS resulted in the release of IL-12 and IL-23 by BMDC but not by BMMΦ. Furthermore, BMDC secreted approx. 20-fold more IL-12p40 and IL-27p28 than BMMΦ. However, BMDC and BMMΦ produced similar levels of IL-10. Using BMDC originating from wild-type (wt), TLR2^def and TLR4^def mice, we show that in BMDC the induction of IL-12, IL-23, and IL-27p28 by SE is dependent on TLR4, whereas low-level production of p40 is also mediated by pattern recognition receptors (PRR) other than TLR4. Interestingly, LPS- and SE-provoked responses of BMDC were remarkably similar indicating that LPS is the primary danger molecule of SE. Taken together, our results point to cDC rather than MΦ as the major producers of the IL-12 family members during in vitro infection with SE. The mechanisms of recognition of SE, however, appear to be the same for cDC and MΦ     

Microbiology of subgingival plaque from children with localized prepubertal periodontitis

Localized prepubertal periodontitis has been described as a host-defect mediated form of bacterially induced periodontitis, with an early onset and rapid progression around a few teeth in children prior to puberty. To further our understanding of the etiology of this disease, we have examined the microbiological components of subgingival dental plaque in 9 children with localized prepubertal periodontitis to determine if patterns of putative pathogens existed, and have compared these results with those obtained from 4 children with no periodontitis. Subgingival plaque samples were plated onto a selective medium for Actinobacillus actinomycetemcomitans and onto a non-selective medium for anaerobes, and the predominant cultivable microbiota of 2 sites per child was determined. The subgingival microbiota of children with localized prepubertal periodontitis clearly differs from non-diseased children in the detection of high levels of several suspected pathogens, including A. actinomycetemcomitans, Bacteroides intermedius, Eikenella corrodens, and Capnocytophaga sputigena. These putative pathogens were found in various combinations. These findings suggest that localized prepubertal periodontitis is associated with specific subgingival bacteria which are generally not found in children without periodontitis.     

2016—2019年瓦房店地区公共场所公共用品用具卫生状况分析

目的 分析大连市瓦房店地区在2016—2019年公共场所公共用具卫生状况,为卫生监督管理提供依据。方法 按照国家双随机抽检要求,2016—2019年在大连市瓦房店地区内抽查公共场所共计352家,进行微生物指标监测和分析。结果 2016—2019年共抽检公共用品用具1 057份,微生物指标合格率92.62%(978/1 057),四年间合格率差异有统计学意义(χ2=7.98,P=0.046),以2018年最高,为94.61%(158/167);不同种类公共用品用具微生物指标合格率差异有统计学意义(χ2=18.55,P<0.001),其中毛巾最低,为87.34%(276/316);不同公共场所微生物指标合格率差异有统计学意义(χ2=10.42,P=0.003),以沐浴场所微生物指标合格率最低,为50.00(3/6)。结论 大连市瓦房店地区公共场所公共用品用具的卫生状况整体良好,沐浴场所以及毛巾类样品超标严重,需要加强消毒管理。