Assessment of oral ciprofloxacin impaired gut barrier integrity on gut bacteria in mice

Gut bacteria and gut barrier plays important roles in body homeostasis. Ciprofloxacin (CPFX) is widely used to treat bacterial infections. However, whether high dosage of CPFX has side effects on gut barrier integrity is still unclear. Our results indicated that the High CPFX treatment (1 mg/ml) caused weight loss, nervousness, anorexia, and increased apoptosis cells in gut, but less influence was observed in the Low CPFX group (0.2 mg/ml). Meanwhile, the High CPFX treatment impaired tight junction molecules Ocln/ZO-1 level and down-regulated antibacterial genes expression (reg3γ, pla2g2α and defb1). Further, the High CPFX treatment increased pro-inflammatory cytokine IL-1β in intestinal tract, decreased IL-17A of duodenum but increased IL-17A of colon at day 37. In addition, the gut bacterial diversity and richness behaved significantly loss regarding CPFX treatment, especially in the High CPFX group during the experiment. Indole exhibited sharply decline in both Low and High CPFX groups at day 7, and the High CPFX mice needed longer time on restoring indole level. Meanwhile, CPFX treatment strongly decreased the concentrations of butyric acid and valeric acid at day 1. Correlation analysis indicated that the linked patterns between the key bacteria (families Bacteroidales_S247, Ruminococcaceae and Desulfovibrionaceae) and metabolites (indole and butyric acid) were disturbed via the CPFX treatment. In conclusion, the High CPFX treatment impaired the gut barrier with the evidence of reduced expression of tight junction proteins, increased apoptosis cells and inflammatory cells, decreased the bacterial diversity and composition, which suggesting a proper antibiotic-dosage use should be carefully considered in disease treatment.     

母亲龋易感性与婴儿口腔微生物多样性关系的纵向探究

目的通过检查有龋及无龋母亲的口腔卫生状况,并通过随访收集其婴儿1个月(1月龄)及6个月(6月龄)的唾液样本测序分析,观察母亲患龋情况对其婴儿口腔微生物多样性的影响。方法通过筛查收集1月龄婴儿的唾液样本;于首次采样时记录母亲的口腔卫生状况,根据母亲患龋情况将婴儿分为母亲有龋组(简称有龋组)和母亲无龋组(简称无龋组),跟踪随访至婴儿6个月时再次收集唾液样本。通过高通量测序的方法,分析婴儿不同月龄微生物多样性的变化。结果本研究随访受试者10例(男6例,女4例),其中有龋组7例,无龋组3例,各组间的微生物群落多样性Shannon指数均无显著性差异(P>0.05)。无龋组婴儿1月龄至6月龄时微生物群落的物种组成有较大变化;有龋组婴儿在1月龄和6月龄时组内各样本间物种组成均差异较大;1月龄时两组微生物群落较相似,而至6月龄时两组婴儿唾液的物种组成已开始发生变化。结论有龋组婴儿口腔内菌群多样性总体高于无龋组,在1月龄至6月龄间婴儿口腔内微生物物种的多样性及丰度均有了不同程度的提高。     

The relationship between nasal and conjunctival cultures of antimicrobial-resistant isolates of methicillin-resistant Staphylococcus aureus

PurposeNasal screening is performed to avoid the complications of postoperative surgical site infections (SSI), especially those due to antimicrobial-resistant species such as methicillin-resistant Staphylococcus aureus (MRSA). This study examined the relationship between bacterial isolates from the conjunctiva and the nasal cavity.MethodsAll patients were diagnosed with ocular surface infections, and the organisms in the conjunctiva and the nasal cavity were isolated. We investigated the relationship of the following antimicrobial-resistant bacteria between the conjunctiva and the nose: MRSA, methicillin-resistant CNS (MRCNS), levofloxacin-resistant (LVFX-R) Corynebacterium spp. Data were analyzed using Fisher’s exact test, and the odds ratio was examined.ResultsThis study included 188 eyes of 188 subjects (87 males and 101 females; mean age 58.5 years, range 11–97 years). MRSA (4 eyes), MRCNS (29 eyes), and LVFX-R Corynebacterium spp. (41 eyes) were identified from the conjunctiva, and MRSA (6 eyes), MRCNS (38 eyes), and LVFX-R Corynebacterium spp. (41 eyes) were identified from the nasal cavity. There was a significant relationship detected between the conjunctiva and the nose for MRSA, MRCNS, and LVFX-R Corynebacterium spp. MRSA displayed high sensitivity (0.750, 95% confidence interval [CI]; 0.301 to 0.987) and specificity (0.984, 95% CI; 0.953 to 0.996) in nasal cavity cultures, and the odds ratio was 181.00 times (95% CI; 18.41 to 2320).ConclusionThis study showed a significant relationship between conjunctival and nasal cultures of MRSA, MRCNS, and LVFX-R Corynebacterium spp., suggesting that nasal cavity culture is a potentially useful screening method for detecting resistant bacteria, especially MRSA, in the conjunctiva.     

应用噬菌体控制假单胞菌的研究进展

假单胞菌属细菌中的部分菌株是动植物和人类的致病菌，也是食品的腐败菌，会导致动植物和人类的高死亡率和严重的食品安全事故。噬菌体作为一种细菌性病毒，特异性高、自我增殖快且无副作用。这些特性使其成为了解决细菌性问题的新思路和新方法。本文就利用噬菌体防控假单胞菌属致病菌和腐败菌在食品、水产、植物、医疗等方面的研究和应用进行综述，以便为后期的深入研究提供一定的参考。     

氨基糖苷类抗生素的发展历程

抗生素的定义，首先来自于20世纪40年代链霉素的发现。在随后的几十年中，其他氨基糖苷类抗生素家族被大量发现并广泛应用，一度成为抗革兰阴性菌感染的首选抗生素。但由于其毒副作用较大，并且细菌对其不断产生耐药性，加上其他结构类别的新型抗生素的不断发现，使其一度几乎退出历史舞台。然而随着多重耐药细菌引起的感染率急剧上升，人们开始关注氨基糖苷类抗生素作为几种重要的治疗革兰阴性病原体的方案之一，并且发掘了其在治疗感染性疾病、艾滋病和遗传性疾病的潜力，使这个“老牌”抗生素重焕生机。     

84例产褥感染的临床特点及常见致病微生物耐药性分析

目的 研究产褥感染的危险因素及常见致病微生物耐药情况，为临床治疗提供参考。方法 回顾性分析我院2017 年1 月～2019 年12 月发生的84 例产褥感染病例的临床资料，与同时期未发生产褥感染的200 例产妇进行对照研究，分析产褥感染的影响因素，并对分离获得的致病微生物进行耐药性分析。结果 感染组妊娠糖尿病、产钳助产、宫口开全后中转剖宫产患者的分布率高于对照组，差异有统计学意义（P＜0.05）；经多因素Logistic 回归分析，妊娠糖尿病是产褥感染的独立影响因素（P＜0.05）。本研究中共检出致病微生物40 株，其中革兰阴性菌13 株（占32.50%），革兰阳性菌10 株（占25.00%），支原体16 株（占40.00%），衣原体1 株（占2.50%），革兰阴性菌中以大肠埃希菌最常见，对二代头孢菌素类抗生素耐药率20%。革兰阳性菌以金黄色葡萄球菌最常见，对青霉素及头孢菌素耐药率高，未发现对亚胺培南及万古霉素耐药。结论 产钳助产、妊娠糖尿病、宫口开全后中转剖宫产是产褥感染可能的危险因素，其中，妊娠糖尿病是产褥感染的独立危险因素。目前临床常见致病微生物谱及耐药率未发生明显变化。     

Association between commensal bacteria and opportunistic pathogens in the dental plaque of elderly individuals

Opportunistic infections in the oral cavity of the elderly may increase the incidence of systemic disease. The objective of this study was to investigate the differences in the oral bacterial flora between dependent elderly (inpatients) and independent elderly (community-dwelling residents). After multiple variables were taken into account, inpatients had significantly lower detection rates than community-dwelling residents for alpha-streptococci (p < 0.001) and Neisseria (p 0.004), and higher detection rates for Pseudomonas aeruginosa (p 0.024), methicillin-resistant Staphylococcus aureus (MRSA) (p 0.011) and Actinomyces spp. (p 0.005). Among inpatients, the requirement for a high degree of care was related negatively to detection of alpha-streptococci, but was related significantly to detection of P. aeruginosa (p 0.018) or MRSA (p 0.004). Tube-fed inpatients had a significantly lower detection rate for alpha-streptococci (p 0.041) and a higher detection rate for P. aeruginosa (p 0.004) than those who did not require tube feeding. Inpatients with a history of antibiotic use had a significantly lower detection rate for alpha-streptococci (p 0.049) and a higher detection rate for MRSA (p 0.007) than those without a history of antibiotic use. The detection rates for P. aeruginosa or MRSA in inpatients without alpha-streptococci were higher than in inpatients with alpha-streptococci after controlling for age and gender (P. aeruginosa, p 0.006; MRSA, p 0.001). Overall, detection of alpha-streptococci had an inverse correlation with the detection of P. aeruginosa and MRSA in the oral cavity and is likely to be an indicator of pathogenic bacterial infection.