Nicotine is a potent extracellular polysaccharide inducer in Fusobacterium nucleatum biofilms

The purpose of this in vitro study was to analyze the influence of nicotine on the extracellular polysaccharides in Fusobacterium nucleatum biofilm. Methods: F. nucleatum (ATCC 10953) biofilms supplemented with different concentrations of nicotine (0, 0.5, 1, 2, 4, and 8 mg/mL) were grown in two different BHI broth conditions [no sucrose and 1% sucrose]. Extracellular polysaccharides assay, pH measurements, and a spectrophotometric assay were performed. Data were submitted for ANOVA and Tukey honestly significant difference analyses (HSD) tests (α =.05). Results: Extracellular polysaccharides synthesis was influenced by an interaction between nicotine concentrations and growth medium solution containing sucrose (P<.05). The pH values declined in the sucrose-exposed biofilm were greater than in the group exposed only to nicotine (P<.05). The biofilm exposed to sucrose and nicotine had a higher total biofilm growth (P<.05) than the nicotine-treated biofilm without sucrose. Conclusions: Regardless of sucrose exposure, biofilms exposed to different nicotine concentrations influenced the amount of extracellular polysaccharides

A new material to prevent urethral damage after implantation of artificial devices: an experimental study

ABSTRACT Objective To validate the application of the bacterial cellulose (BC) membrane as a protecting barrier to the urethra. Materials and Methods Forty female Wistar rats (four groups of 10): Group 1 (sham), the urethra was dissected as in previous groups and nothing applied around; Group 2, received a 0.7cm strip of the BC applied around the urethra just below the bladder neck; Group 3, received a silicon strip with the same dimensions as in group 2; Group 4, had a combination of 2 and 3 groups being the silicon strip applied over the cellulosic material. Half of the animals in each group were killed at 4 and 8 months. Bladder and urethra were fixed in formalin for histological analysis. Results Inflammatory infiltrates were more intense at 4 months at lymphonodes (80% Grade 2), statistically different in the group 2 compared with groups 1 (p=0.0044) and 3 (p=0.0154). At 8 months, all samples were classified as grade 1 indicating a less intense inflammatory reaction in all groups. In group 2, at 8 months, there was a reduction in epithelial thickness (30±1μm) when com-pared to groups 1 (p=0.0001) and 3 (p<0.0001). Angiogenesis was present in groups 2 and 4 and absent in group 3. In BC implant, at 4 and 8 months, it was significant when comparing groups 4 with 1 (p=0.0159). Conclusion BC membrane was well integrated to the urethral wall promoting tissue remodeling and strengthening based on morphometric and histological results and may be a future option to prevent urethral damage.

Detection of capsular serotype and virulence gene of Klebsiella pneumonia with hypermucoviscosity phenotype / 中华检验医学杂志

Objective To detect the hypermucoviscosity phenotype , capsular serotype and virulence gene of Klebsiella pneumonia (K.pneumonia) from various kinds of clinical specimens and understand the characteristics of different K.pneumonia causing infections.Methods A retrospective study was conducted through collection of 178 K.pneumonia isolates from blood, sputum, bronchoalveolar lavage fluid , urine, normally sterilized fluid , puncture fluid from liver abscess and other abscesses between January 2010 and December 2012 in General Hospital of Chinese PLA.String test was carried out for detection of hypermucoviscosity phenotype.Capsular serotype and virulence gene ( rmpA) were checked by polymerase chain reaction.Analysis was made according to the hypermucoviscosity , capsular serotype , rmpA gene , as well as the sources of K.pneumoniae.Statistic data was analyzed by contingency table analysis and χ2 test.Results Eighty-three out of 178 ( 46.6%) strains of K.pneumonia were hypermucoviscous with positive string test, the positive rate of virulence gene rmpA was 92.8%(77/83).K1/K2/K57 capsular serotypes were the predominant serotypes in the group of puncture fluid from liver abscess and other abscesses (75.0%,27/36)than the group of blood (32.4%,12/37), urine(21.7%,5/23) and normally sterilized fluid(25.0%,5/20), and also more than in the group of sputum , bronchoalveolar lavage fluid (50.0%,22/44),χ2 =21.19,P<0.01.The positive rate of string test in the group of puncture fluid from liver abscess and other abscesses (77.8%, 28/36)was significantly higher than the group of blood (29.7%, 11/37), urine (30.4%, 7/23), or normally sterilized fluid (25.0%, 5/20),χ2 =27.90,P<0.01.The positive rate of rmpA gene in the isolates from puncture fluid of liver abscess and other abscesses was higher than other groups.Conclusions As the pathogens of various kinds of infections , mainly abscess and respiratory infection, hypermucoviscous strains of K.pneumonia were of great clinical significance.Capsular serotype K57, as well as K1 and K2, possessed hypermucoviscosity and hypervirulence in China.

Clinical Implications of Pneumococcal Serotypes: Invasive Disease Potential, Clinical Presentations, and Antibiotic Resistance

Streptococcus pneumoniae can asymptomatically colonize the nasopharynx and cause a diverse range of illnesses. This clinical spectrum from colonization to invasive pneumococcal disease (IPD) appears to depend on the pneumococcal capsular serotype rather than the genetic background. According to a literature review, serotypes 1, 4, 5, 7F, 8, 12F, 14, 18C, and 19A are more likely to cause IPD. Although serotypes 1 and 19A are the predominant causes of invasive pneumococcal pneumonia, serotype 14 remains one of the most common etiologic agents of non-bacteremic pneumonia in adults, even after 7-valent pneumococcal conjugate vaccine (PCV7) introduction. Serotypes 1, 3, and 19A pneumococci are likely to cause empyema and hemolytic uremic syndrome. Serotype 1 pneumococcal meningitis is prevalent in the African meningitis belt, with a high fatality rate. In contrast to the capsule type, genotype is more closely associated with antibiotic resistance. CC320/271 strains expressing serotype 19A are multidrug-resistant (MDR) and prevalent worldwide in the era of PCV7. Several clones of MDR serotype 6C pneumococci emerged, and a MDR 6D clone (ST282) has been identified in Korea. Since the pneumococcal epidemiology of capsule types varies geographically and temporally, a nationwide serosurveillance system is vital to establishing appropriate vaccination strategies for each country.

Influences of Lyciun Barbarian Polysaccharide, Astragalus Polysaccharide, Polysaccharide of Acanthopanax Senticosus and Polysaccharide of Lipopolysaccharide on the Induction of LAK Cells in vitro / 第二军医大学学报

Effects of Lycium barbarian polysaccharide (LBP), Astragalus polysaccharide (APS), polysaccharide of Acanthopanax senticosus (PAS) and polysaccharide of lipopolysaccharide (PS) on cytotoxicities of LAK cells from splenocytes of C57BL/6 mices were observed with 18 h 125IUdR release assay. Our study demonstrated that the polysaccharides alone were shown to induce no cytotoxicities. When combined with rIL-2, all of 4 kinds of the polysaccharides augrnented LAK activities in dose-dependent manner. The augmentations reached the maximum at 0.01-0.1 mg ? ml-1 LBP, 0.01 mg ? ml-1 APS and PAS, 0.01 mg ? ml-1 PS. They were found to increase LAK activities in short range of rIL-2 concentrations (250-1000U? ml-1). If the polysaccharides were used beyond the suitable concentrations, they were shown to inhibit LAK cell activities.