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EBS؉ ) exhibited plasmid segregation that was as extensive in vivo as in vitro. These data suggest that AS and EBS do not contribute to upper or lower urinary tract colonization by E. faecalis and that growth in urine does not induce AS expression by strains carrying plasmids in the pCF10 family.Enterococcus, a leading cause of hospital-acquired infections, is associated specifically with urinary tract infection (UTI), device-related infections, bacteremia, and endocarditis (16). Putative virulence factors include gelatinase, cytolysin, capsule, hyaluronidase, the fsr quorum-sensing system, enterococcal surface protein (Esp), and aggregation substance (AS) (2, 3, 6, 8, 12, 14, 17-20, 24, 25, 27, 28, 30-32). A role in urovirulence has been directly demonstrated only for Esp (24), but AS also may conceivably have a role in UTI pathogenesis. AS is a plasmid-encoded enterococcal surface protein that interacts with enterococcal binding substance (EBS), its cognate receptor on other enterococci, to form mating complexes. Enterococci containing an AS-encoding sex plasmid express AS when stimulated by a peptide pheromone secreted from other enterococci, whereas most enterococci constitutively express EBS (7, 15). AS is epidemiologically associated with UTI (6), increases enterococcal adherence to cultured renal tubular cells (14), and protects Enterococcus faecalis from killing by polymorphonuclear leukocytes (19), an important urinary tract defense element. However, AS has not been directly assessed as a urovirulence factor. We therefore sought to determine whether the AS-EBS combination enhances urinary tract colonization by E. faecalis.Strains. Four derivatives of OG1SSp, a streptomycin-spectinomycin-resistant mutant of wild-type E. faecalis strain OG1 (4), were studied (Table 1). These included two transformants of OG1SSp, one with pCF500 (a derivative of wild-type pheromone plasmid pCF10 that, like pCF10, confers pheromoneinducible AS expression and, in addition, has a selectable erythromycin resistance marker) and the other with pINY1801, which contains a fragment of pCF10 cloned into shuttle vector pWM401 and constitutively expresses AS (4, 23). Also studied were INY3000, an EBS-deficient Tn916 mutant of OG1SSp (1, 29) and a transformant of INY3000 containing shuttle vector pWM401 (23,29).Mouse model. The mouse model of ascending unobstructed UTI has been described previously (13,21). Both dual-strain and single-strain bacterial challenges were used. Female CBA/J or Swiss Webster mice were inoculated perurethrally by an infusion pump with broth-grown bacteria. The absence of vesico-ureteral reflux was confirmed by immediate postinoculation kidney cultures. For colonization experiments, urine, bladder, and kidneys were harvested sterilely at 24 h, 48 h, or 5 days postinoculation and cultured quantitatively with appropriate media (13,21).The bacteria for inoculation were grown at 37°C in tryptic soy broth or Todd-Hewitt broth (THB) either to mid-log phase or overnight and then pelleted. For competition experiments,...

The aims of this retrospective study, conducted in 2017, were to explore dental students’ perceptions of their first standardized patient encounters and to assess the relationship between students’ self-evaluation and faculty members’ evaluation of students’ communication skills in those encounters. Data from a simulation training laboratory at one U.S. dental school were obtained for all 46 second-year students, who had a standardized patient communication learning session. The students had completed self-evaluations before and after a debriefing with a clinical psychology and/or social work faculty member and three or four student peers. The faculty members had also completed evaluations of the students’ communications skills. The results showed that the students found the standardized patient encounter helpful. The students rated “making an introduction” most positively. Students had a weighted Kappa agreement of 0.22 (p=0.024) with the faculty evaluations on their post-debriefing evaluation of overall communication skills, which was within the 0.21–0.40 range of fair agreement. This study found that, during their first standardized patient simulation exercise, the second-year students rated their overall communication skills in fair agreement with the faculty member after debriefing.

Introduction. The unknown effects of electronic cigarettes are public health concerns. One potential effect of electronic cigarette fluid constituents, such as nicotine, may influence sleep. The purpose of this study is to determine if there is an association between sleep duration and electronic cigarette use. Methods. A retrospective, cross-sectional study was conducted using National Health and Nutrition Examination Survey (NHANES) 2015-2016. Variables of interest included responses to questions concerning electronic cigarette use, hours of sleep, and other variables associated with sleep. Data analyses were conducted with the Rao-Scott chi square test and logistic regression. Results. This study was conducted on 2889 participants, aged 18-65 years, of whom 50.7% were female. Using a bivariate analyses of electronic cigarette usage and sleep duration, participants who never used an electronic cigarette were more likely to have appropriate sleep durations as compared with participants who were currently using electronic cigarettes (P<0.0001). After adjusting for sociodemographic variables and cigarette smoking, current electronic cigarette use was associated with higher odds of less sleep duration (adjusted odds ratio=1.82; 95% CI: 1.18, 2.79; P=0.0075). Conclusions. Participants currently using electronic cigarettes are more likely to have less sleep as compared to participants who have never used electronic cigarettes. Implications. With sleep time duration being a major factor for proper body function and repair, this study can serve as confirmation that the use of electronic cigarettes is not a harmless health behavior.

The endotracheal tube (ETT) is recognized as an independent factor for infection in intubated patients. The presence of biofilm contributes to the development of pneumonia. Standard culturing techniques are inadequate to detect many of the bacteria present in a biofilm. Delineation of the microbiota in the ETT is needed to further understand infections in ventilated patients. A prospective, observational study was performed at a university, Level I trauma center. Twenty ETT were collected at extubation. Bioluminal accretions were removed and quantified. DNA was extracted and 16S ribosomal RNA gene analysis performed using the Human Oral Microbe Identification Microarray. Twenty ETTwere evaluated. Mean age was 47.5 years (19–82). Five were smokers. Mean ventilator days was 3.6 ± 3.1. Mean intensive care unit days was 7.8 ± 6.3. In those ETT, 87 different bacterial species were identified. Mean number of bacterial species identified was 16 ± 9 (3–35). There was no relationship between duration of intubation and number of species ( P = 0.5). Nonsmokers had a greater variety of bacteria than smokers ( P = 0.03). Patients with pneumonia did not have a greater variety of bacteria ( P = 0.14). Parvimonas micra presence was associated with reintubation ( P = 0.01). The most common species in smokers were different from nonsmokers. There is a wide variety of bacteria present in an ETT, many of which cannot be cultured by standard means. Variation is not correlated to duration of intubation or accretion volume. Studies to evaluate these bacteria and their interaction with the biofilm may further delineate factors in development of infections.