A new aspect of in vitro antimicrobial leukocyte- and platelet-rich plasma activity based on flow cytometry assessment

The current literature suggests that the antibacterial effect of leukocyte- and platelet-rich plasma (L-PRP) is directly related to platelet and leukocyte concentrations. The aim of this study was twofold: first, to evaluate the antimicrobial effect of L-PRP against selected bacterial strains in vitro, and second, to correlate this effect with leukocyte and platelet content in the final concentration. Blood was collected from 20 healthy males, and L-PRP, acellular plasma (AP), and autologous thrombin were consecutively prepared. Flow cytometry analysis of the blood, L-PRP, and AP was performed. The L-PRP gel, liquid L-PRP, and thrombin samples were tested in vitro for their antibacterial properties against seven selected bacterial strains using the Kirby–Bauer disk-diffusion method. There was notable antimicrobial activity against selected bacterial strains. No statistically significant correlations between antimicrobial activities and the platelet concentration in L-PRP were observed. Statistically significant positive correlations between selected leukocyte subtypes and antimicrobial activity were noted. A negative correlation was found between elevated monocyte count and antimicrobial activity of L-PRP against one bacterial strain studied. L-PRP possesses antimicrobial activity and can be potentially useful in the fight against certain postoperative infections. The bactericidal effect of L-PRP is caused by leukocytes, and there exists a relationship among selected leukocyte subtypes and L-PRP antimicrobial activity.     

脊柱化脓性感染动物模型的建立及应用进展

手术部位感染是脊柱手术后常见且非常严重的并发症,严重影响患者的身体健康。尽管手术操作无菌细致,及时给予适当的全身抗生素,但手术部位感染率仍然很高[1-2]。据报道,我国脊柱手术感染的风险从0.5%~7.8%不等[3-4]。糖尿病、肥胖、高血压等疾病显著增加脊柱术后感染,感染后治疗的费用可达10多万美元[5],大大增加了患者的经济负担。     

反复粪便培养金黄色葡萄球菌阳性老年患者口服万古霉素效果评价

目的 通过探讨肠道非急性感染期反复粪便培养金黄色葡萄球菌阳性的老年患者口服万古霉素的效果，为此类患者提供一种潜在的治疗方案。方法 前瞻性分析吉林大学第一医院干部病房2015 年9 月～2018 年12 月收治的186 例肠道非急性感染期反复粪便培养金黄色葡萄球菌阳性的老年患者。根据是否口服万古霉素治疗分为万古组和对照组。收集两组患者的一般临床资料，比较两组患者试验前后万古霉素血药浓度、血常规、降钙素原（PCT）、C 反应蛋白（CRP），试验期间粪便培养结果、体温、抗生素使用情况。结果 试验治疗期间，万古组便培养转阴率高于对照组，差异有统计学意义（P＜0.05）；万古组发热率（29.75%）低于对照组的34.77%，差异有高度统计学意义（P＜0.01）；万古组抗生素使用率（4.49%）低于对照组的19.23%，差异有高度统计学意义（P＜0.01）。试验前两组白细胞、中性粒细胞计数、中性粒细胞比例、PCT、CRP 比较，差异无统计学意义（P＞0.05）；试验后万古组白细胞、中性粒细胞计数、中性粒细胞比例、CRP 低于对照组，差异有高度统计学意义（P＜0.01）。试验后万古组白细胞、中性粒细胞计数、中性粒细胞比例、CRP 低于试验前，差异有高度统计学意义（P＜0.01）。结论 口服万古霉素可能提高肠道非急性感染期反复粪便培养金黄色葡萄球菌阳性的老年患者粪便转阴率，减少发热及抗生素的应用，降低炎症细胞水平，可能是此类患者一种潜在的临床治疗方案。     

Therapeutics and delivery vehicles for local treatment of osteomyelitis

Osteomyelitis, or the infection of the bone, presents a major complication in orthopedics and may lead to prolonged hospital visits, implant failure, and in more extreme cases, amputation of affected limbs. Typical treatment for this disease involves surgical debridement followed by long-term, systemic antibiotic administration, which contributes to the development of antibiotic-resistant bacteria and has limited ability to eradicate challenging biofilm-forming pathogens including Staphylococcus aureus—the most common cause of osteomyelitis. Local delivery of high doses of antibiotics via traditional bone cement can reduce systemic side effects of an antibiotic. Nonetheless, growing concerns over burst release (then subtherapeutic dose) of antibiotics, along with microbial colonization of the nondegradable cement biomaterial, further exacerbate antibiotic resistance and highlight the need to engineer alternative antimicrobial therapeutics and local delivery vehicles with increased efficacy against, in particular, biofilm-forming, antibiotic-resistant bacteria. Furthermore, limited guidance exists regarding both standardized formulation protocols and validated assays to predict efficacy of a therapeutic against multiple strains of bacteria. Ideally, antimicrobial strategies would be highly specific while exhibiting a broad spectrum of bactericidal activity. With a focus on S. aureus infection, this review addresses the efficacy of novel therapeutics and local delivery vehicles, as alternatives to the traditional antibiotic regimens. The aim of this review is to discuss these components with regards to long bone osteomyelitis and to encourage positive directions for future research efforts.     

Antibacterial activities of the leaf extracts of Eugenia uniflora Linn. (Synonym Stenocalyx michelli Linn.) Myrtaceae

The aqueous, organic, and volatile oil extracts of leaves of Eugenia uniflora Linn. Family Myrtaceae were investigated for antibacterial properties using agar dilution techniques. The aqueous extract was the most active against the organisms compared to the organic and volatile oil extracts. The extracts were found to inhibit Gram positive Staphylococcus aureus and Bacillus subtilis and Gram negative Escherichia coli and Shigella dysentcriae. Pseudomonas aeruginosa, Klebsiella pneumoniac, and Salmonella typhi were not inhibited.     

仙草消毒液杀灭微生物效果与毒性的试验观察

仙草消毒液为含 3 0 %乙醇的植物消毒剂 ,其中包括五味子、细辛、丁香等成分 ,p H6.0 1。为了解其杀灭微生物效果及其毒性 ,进行了载体定量杀菌试验及毒性试验。结果 ,1∶ 1的水稀释液对金黄色葡萄球菌作用2分钟 ,1∶ 2的稀释液对金黄色葡萄球菌作用 8分钟 ,以其原液对白色念珠菌作用 2 min,平均杀灭率均大于99.90 %。小牛血清对其杀灭效果有影响 ,原液经 5 4℃存放 14天 ,杀菌效果无明显变化。以其原液对雌、雄小鼠经口 LD50 >5 0 0 0 mg/Kg,对大耳白兔一次眼、皮肤刺激试验平均积分指数为 0 ,微核试验阴性 ,蓄积毒性试验为弱蓄积毒性     

压电基因传感器阵列检测MRSA的实验研究

目的：探讨以压电传感阵列技术检测耐甲氧西林葡萄球菌的可行性。方法：收集临床64株葡萄球菌标本，对其耐药标志基因mecA基因和金黄色葡萄球菌特有基因femA增后应用压电传感器阵列进行检测，并以PCR电泳检测作参照，与目前采用的常规药物敏感试验进行对比分析。结果：传感器分析与PCR电泳分析结果完全一致，而此两种方法与常规培养加药敏法比较。结果略有差异。所有64株葡萄球菌中，2株耐甲氧西林金黄色葡萄球菌（MRSA）的mecA为阴性，2株甲氧西林敏感金黄色葡萄球菌（MSSA)的mecA为阳性，1株耐甲氧西林凝固酶性葡萄球菌（MRCNS）的mecA为阴性；2株甲氧西林敏感凝固酶阴性葡萄球菌（MSCNS）的mecA为阳性。结论：以压电传感阵列技术同时检测femA基因和mecA基因，既可鉴定出是否为金黄色葡萄球菌，又可判断其耐药类型，能为危重病人感染MRSA时的诊断和治疗提供依据。     

荧光原位杂交法快速鉴定血培养阳性葡萄球菌的临床应用

目的快速鉴定血培养中的金黄色葡萄球菌和凝固酶阴性葡萄球菌(CoNS),结合临床快速判定是否为污染菌。方法采用荧光原位杂交法鉴定血培养中的金黄色葡萄球菌和CoNS,杂交结果若为CoNS,根据临床资料进行判断,并与文献推荐的污染判断法进行结果比较。结果探针的特异性经由标准菌株和临床分离菌株证实。金黄色葡萄球菌探针的特异性和敏感性均为100%,GoNS探针的特异性和敏感性分别为100%和95.5%。179株CoNS中117株判断为污染菌,污染率为68%,与文献推荐的污染判断方法一致。结论荧光原位杂交法适用于血培养中的金黄色葡萄球菌和CoNS的快速鉴定,以排除CoNS污染。     

In vitro anti‐adhesive activity of green tea extract against pathogen adhesion

Camellia sinensis polysaccharide has been reported to possess anti‐adhesive activity against pathogens. The present study was designed to investigate whether hot water extracts obtained from green tea leaves might inhibit pathogen adhesion to human or mouse cell lines. Green tea extract‐4 (CSI‐4) with the maximum yield of 4% (w/v) is composed of a major proportion of carbohydrates containing 40% uronic acids, but lack of catechins. It showed strong inhibitory activities against hemagglutination mediated by pathogens Helicobacter pylori, Propionibacterium acnes and Staphylococcus aureus with the minimum inhibitory concentrations of 0.01‐0.5 mg/mL. CSI‐4 further demonstrated an inhibitory effect on the adhesion of these pathogens to host cell lines with the IC₅₀ values (50% inhibition of adhesion) of 0.14–2.3 mg/mL. It exhibited the highest activity against P. acnes, but no inhibitory effects were observed against Lactobacillus acidophilus, Bifidobacterium bifidum, Escherichia coli, or Staphylococcus epidermidis. Our results suggest that CSI‐4 may exert a selective anti‐adhesive effect against certain pathogenic bacteria with no adverse effects against beneficial or commensal bacteria. Copyright © 2008 John Wiley & Sons, Ltd.