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Helen A. Fletcher Rachel Tanner Robert S. Wallis Joel Meyer Zita-Rose Manjaly Stephanie Harris Iman Satti Richard F. Silver Dan Hoft Beate Kampmann K. Barry Walker Hazel M. Dockrell Uli Fruth Lew Barker Michael J. Brennan Helen McShane 《Clinical and Vaccine Immunology : CVI》2013,20(11):1683-1689
Despite the widespread use of the Mycobacterium bovis BCG vaccine, there are more than 9 million new cases of tuberculosis (TB) every year, and there is an urgent need for better TB vaccines. TB vaccine candidates are selected for evaluation based in part on the detection of an antigen-specific gamma interferon (IFN-γ) response. The measurement of mycobacterial growth in blood specimens obtained from subjects immunized with investigational TB vaccines may be a better in vitro correlate of in vivo vaccine efficacy. We performed a clinical study with 30 United Kingdom adults who were followed for 6 months to evaluate the abilities of both a whole-blood- and a novel peripheral blood mononuclear cell (PBMC)-based mycobacterial growth inhibition assay to measure a response to primary vaccination and revaccination with BCG. Using cryopreserved PBMCs, we observed a significant improvement in mycobacterial growth inhibition following primary vaccination but no improvement in growth inhibition following revaccination with BCG (P < 0.05). Mycobacterial growth inhibition following primary BCG vaccination was not correlated with purified protein derivative (PPD) antigen-specific IFN-γ enzyme-linked immunospot (ELISPOT) responses. We demonstrate that a mycobacterial growth inhibition assay can detect improved capacity to control growth following primary immunization, but not revaccination, with BCG. This is the first study to demonstrate that an in vitro growth inhibition assay can identify a difference in vaccine responses by comparing both primary and secondary BCG vaccinations, suggesting that in vitro growth inhibition assays may serve as better surrogates of clinical efficacy than the assays currently used for the assessment of candidate TB vaccines. 相似文献
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Aude-Marine Paepegaey Matthew L. Barker David W. Bartlett Miten Mistry Nicola X. West Nicola Hellin Louise J. Brown Philip G. Bellamy 《Dental materials》2013
Objectives
To compare three instruments for their ability to quantify enamel loss after acid erosion.Methods
6 randomized parallel groups of bovine enamel samples were subjected to citric acid (higher acidity) or orange juice (lower acidity) erosion and remineralisation in a cycling model. Two protected shoulders were created on each of the samples using tape, to serve as reference for analysis. The time of exposure to each acid was varied, along with presence or absence of agitation. After treatment, samples were measured on 3 instruments capable of measuring step height: a contact profilometer (CP); a non-contact profilometer (NCP); and a confocal laser scanning microscope (CLSM) by three different examiners. Additionally, 3D (volume) step height was also measured using the CLSM.Results
Increasing acid concentration and exposure time resulted in greater erosion, as did agitation of samples while in acid solution. All instruments/methods identified the same statistically significant (p < 0.05) pair-wise differences between the treatments groups. Further, all four methods exhibited strong agreement (Intra-class correlation ≥ 0.96) in erosion level and were highly correlated, with correlations of 0.99 or higher in all cases.Significance
All instruments/methods used in this study produced very similar conclusions with regard to ranking of enamel loss, with data showing very high agreement between instruments. All instruments were found to be equally suited to the measurement of enamel erosion. 相似文献214.
Halvorson SA Ricker MA Barker AF Patton PE Harrison RA Hunter AJ 《Journal of general internal medicine》2012,27(5):603-607
Thoracic endometriosis syndrome is a well-described, rare manifestation of endometriosis. We present a case of a 35-year old
woman undergoing controlled ovarian stimulation prior to in vitro fertilization (IVF) who developed bilateral hemorrhagic
pleural effusions. She was initially diagnosed with ovarian hyperstimulation syndrome, a complication of infertility therapy;
however, she was later found to have occult thoracic endometriosis. We describe ovarian hyperstimulation syndrome and review
the manifestations of thoracic endometriosis syndrome. Although endometriosis is a hormone-dependent disease, the rate of
IVF complications related to endometriosis is low. 相似文献
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In March 2010, the Patient Protection and Affordable Care Act as well as its amendments were signed into law. This sweeping legislation was aimed at controlling spiraling healthcare costs and redressing significant disparities in healthcare access and quality. Cancer diagnoses and their treatments constitute a large component of rising healthcare expenditures and, not surprisingly, the legislation will have a significant influence on cancer care in the USA. Because genitourinary malignancies represent an impressive 25% of all cancer diagnoses per year, this legislation could have a profound impact on urologic oncology. To this end, we will present key components of this landmark legislation, including the proposed expansion to Medicaid coverage, the projected role of Accountable Care Organizations, the expected creation of quality reporting systems, the formation of an independent Patient-Centered Outcomes Research Institute, and enhanced regulation on physician-owned practices. We will specifically address the anticipated effect of these changes on urologic cancer care. Briefly, the legal ramifications and current barriers to the statutes will be examined. 相似文献
219.
Jennifer L. Cleveland Misty Foster Laurie Barker G. Gordon Brown Nancy Lenfestey Linda Lux Tammy J. Corley Arthur J. Bonito 《Journal of the American Dental Association (1939)》2012,143(10):1127-1138
Background and OverviewThe authors set out to identify factors associated with implementation by U.S. dentists of four practices first recommended in the Centers for Disease Control and Prevention's Guidelines for Infection Control in Dental Health-Care Settings—2003.MethodsIn 2008, the authors surveyed a stratified random sample of 6,825 U.S. dentists. The response rate was 49 percent. The authors gathered data regarding dentists' demographic and practice characteristics, attitudes toward infection control, sources of instruction regarding the guidelines and knowledge about the need to use sterile water for surgical procedures. Then they assessed the impact of those factors on the implementation of four recommendations: having an infection control coordinator, maintaining dental unit water quality, documenting percutaneous injuries and using safer medical devices, such as safer syringes and scalpels. The authors conducted bivariate analyses and proportional odds modeling.ResultsResponding dentists in 34 percent of practices had implemented none or one of the four recommendations, 40 percent had implemented two of the recommendations and 26 percent had implemented three or four of the recommendations. The likelihood of implementation was higher among dentists who acknowledged the importance of infection control, had practiced dentistry for less than 30 years, had received more continuing dental education credits in infection control, correctly identified more surgical procedures that require the use of sterile water, worked in larger practices and had at least three sources of instruction regarding the guidelines. Dentists with practices in the South Atlantic, Middle Atlantic or East South Central U.S. Census divisions were less likely to have complied.ConclusionsImplementation of the four recommendations varied among U.S. dentists. Strategies targeted at raising awareness of the importance of infection control, increasing continuing education requirements and developing multiple modes of instruction may increase implementation of current and future Centers for Disease Control and Prevention guidelines.The findings and conclusions in this report are those of the authors and do not necessarily represent the official position of the Centers for Disease Control and Prevention, Atlanta.The authors thank Jon Ruesch, who when this study was conducted was the director, Survey Center, American Dental Association, Chicago, for his effort in the collection of the data for this research project. Mr. Ruesch is now retired. 相似文献
220.
Adams SH Rowe CR Gansky SA Cheng NF Barker JC Hyde S 《Journal of public health dentistry》2012,72(3):252-260
Our prior research focused on parental treatment acceptability (TA) and treatment preferences (TPs) for preventive dental treatments for young Hispanic children. We adapted the interview for administration to parents of young African‐American children. Objective: In a sample of African‐American parents, determine parental TA and TP for five dental treatments to prevent early childhood caries. Methods: Interviewed 48 parents/caregivers of African‐American children attending Head Start, assessing TA and TP for three treatments for children: toothbrushing (TB) with fluoride toothpaste, fluoride varnish (FV), and xylitol in food (XF); and two treatments for mothers: xylitol gum (XG) and chlorhexidine (CHX) rinse. The interview included verbal information, illustrated treatment cards, photos/video clips, and samples. Parents provided TA of each treatment (one to five scale), TP between each of 10 pairs of the five treatments, and open‐ended reasons for their preferences. TPs were summed (zero to four) to create overall preference. Results: All treatments were acceptable (means 4.4‐4.9). TB was more acceptable than FV and XF (P < 0.05). Summed TP revealed a strong preference for TB (mean 3.1) above other treatments (all P < 0.01). Primary reasons for preferring TB were the following: promotes healthy habits; child focused; and effectiveness. Conclusions: All treatments were acceptable, however, parents/guardians strongly preferred TB. Parents' emphasis on healthy habits and child‐focused treatment supports efforts for oral health education programs in early childhood settings. Some parents expressed concerns about FV, XF, and CHX. Results may be useful in planning prevention programs for young children in African‐American communities. 相似文献