Intensity and duration of in‐vitro antibacterial activity of different adhesives used in orthodontics

This work investigated the antibacterial activity of 14 bonding agents to predict their ability to inhibit white‐spot development during orthodontic treatment. Standardized, sterilized disks of each material were continuously rinsed (for up to 180 d) in a flow of sterile saline. At predetermined time points, the residual ability of each material to inhibit bacterial growth (determined by measuring the size of inhibition halos around disks placed onto appropriate culture media seeded with Streptococcus gordonii DSM6777, Streptococcus sanguinis DSM20567, Streptococcus mutans DSM20523, or Lactobacillus acidophilus DSM20079) and biofilm formation (determined by measuring the numbers of bacteria adherent to disks following incubation in appropriate broths) was tested in triplicate and compared with the baseline activities of freshly prepared materials. Overall antibacterial and anti‐biofilm activities, adjusted for exposure time and strain of bacteria, were assessed. The decrease of antibacterial activity was faster (30–60 d) and complete for fluoride‐enriched materials, but slower (90 d) and partial for antimicrobial‐containing materials (benzalkonium chloride, zinc oxide, chlorexidine, or MDPB). Materials enriched with benzalkonium chloride, chlorexidine, or MDPB showed the highest antibacterial activities. Anti‐biofilm assays yielded similar results. These data could be helpful for clinicians in the choice of the best performing bonding agent also in light of duration of the clinical application.     

进行性斑状色素减少症发病机制初步探讨

目的探讨进行性斑状色素减少症(progressive macular hypomelanosis,PMH)患者皮损中分离出的痤疮丙酸杆菌对人角质形成细胞(human keratinocytes,HaCaT)细胞分泌干扰素(interferon,IFN)-γ、白细胞介素(interleukin,IL)-6、肿瘤坏死因子(tumor necrosis factor,TNF)-α的影响。方法体外培养HaCaT细胞株,分别加入分离自PMH的痤疮丙酸杆菌、痤疮丙酸杆菌标准菌株(NCTC737),酶联免疫吸附试验(enzyme-linked immunosorbent assay,ELISA)方法测定细胞上清液中IFN-γ、IL-6、TNF-α的分泌量。结果 PMH患者中分离的痤疮丙酸杆菌与角质形成细胞HaCaT细胞株共培养后,能促进角质形成细胞分泌IFN-γ和IL-6,与空白组比较,有明显升高,差异有统计学意义(P0.05);与痤疮丙酸杆菌标准菌株NCTC737相比也升高,差异有统计学意义(P0.05)。结论进行性斑状色素减少症皮损中分离出的痤疮丙酸杆菌可刺激HaCaT细胞分泌IFN-γ、IL-6、TNF-α,提示可能是皮损色素减退的原因之一。     

Transmission of Brucellosis from Elk to Cattle and Bison,Greater Yellowstone Area,USA, 2002–2012

Bovine brucellosis has been nearly eliminated from livestock in the United States. Bison and elk in the Greater Yellowstone Area remain reservoirs for the disease. During 1990–2002, no known cases occurred in Greater Yellowstone Area livestock. Since then, 17 transmission events from wildlife to livestock have been investigated.     

Three Outbreak-causing Neisseria meningitidis Serogroup C Clones,Brazil

During 2003–2012, 8 clusters of meningococcal disease were identified in Rio de Janeiro State, Brazil, all caused by serogroup C Neisseria meningitidis. The isolates were assigned to 3 clonal complexes (cc): cc11, cc32, and cc103. These hyperinvasive disease lineages were associated with endemic disease, outbreaks, and high case-fatality rates.     

Dendritic cell-based active specific immunotherapy for malignant glioma

Recent advances in genetic modification technology show that lactic acid bacteria can constitutively produce functional, eukaryote-derived proteins without any apparent negative effect on bacterial growth and physiology. These bacteria appear capable of surviving and of being physiologically active at the mucosal surfaces of higher eukaryotes. Studies in animal models also suggest that these findings could have a major impact in human medicine. Alongside conceptual proofs, the development of a robust system for biological containment will allow for the examination of genetically modified lactic acid bacteria as vectors of therapeutic protein delivery in human healthcare.     

微生物检验泌尿系统的病原菌结果研究

目的探究微生物检验泌尿系统病原菌的结果。方法选取2019年6月至2020年3月本院泌尿科收治的120例泌尿系统感染患者为研究对象。使用实验室微生物检测其泌尿系统的病原菌,比较泌尿系统病原菌的类型与药敏试验结果。结果120株病原菌中革兰阴性菌65株(54.17%),革兰阳性菌30株(25.00%),假丝酵母菌25株(20.83%)。革兰阴性菌中大部分为大肠埃希菌(76.92%);革兰阳性菌中大部分为鸟肠球菌(40.00%);假丝酵母菌中大部分为白假丝酵母菌(52.00%);通过药敏试验发现,对亚胺培南与阿米卡星敏感度较高的是大肠埃希菌,对头孢他啶、阿莫西林与舒巴坦敏感度较高的是鸟肠球菌;对头孢呋辛、替考拉宁和青霉素G敏感度较高的是白假丝酵母菌。结论泌尿系统感染疾病的主要致病菌是革兰阴性菌和革兰阳性菌,因此,在对有泌尿系统感染症状患者的临床诊断与治疗过程中应对患者的病原菌实施实验室微生物检测,从而选择合适的抗菌药物。     

Epidemiology of Primary Multidrug-Resistant Tuberculosis,Vladimir Region,Russia

We studied the epidemiology of drug-resistant tuberculosis (TB) in Vladimir Region, Russia, in 2012. Most cases of multidrug-resistant TB (MDR TB) were caused by transmission of drug-resistant strains, and >33% were in patients referred for testing after mass radiographic screening. Early diagnosis of drug resistance is essential for preventing transmission of MDR TB.     

Influence of Humans on Evolution and Mobilization of Environmental Antibiotic Resistome

The clinical failure of antimicrobial drugs that were previously effective in controlling infectious disease is a tragedy of increasing magnitude that gravely affects human health. This resistance by pathogens is often the endpoint of an evolutionary process that began billions of years ago in non–disease-causing microorganisms. This environmental resistome, its mobilization, and the conditions that facilitate its entry into human pathogens are at the heart of the current public health crisis in antibiotic resistance. Understanding the origins, evolution, and mechanisms of transfer of resistance elements is vital to our ability to adequately address this public health issue.