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91.

Background

Dental caries is one of the primary causes of tooth loss among adults. It is estimated to affect a majority of Americans aged 55 and older, with a disproportionately higher burden in disadvantaged populations. Although a number of treatments are currently in use for caries prevention in adults, evidence for their efficacy and effectiveness is limited.

Methods/Design

The Prevention of Adult Caries Study (PACS) is a multicenter, placebo-controlled, double-blind, randomized clinical trial of the efficacy of a chlorhexidine (10% w/v) dental coating in preventing adult caries. Participants (n = 983) were recruited from four different dental delivery systems serving four diverse communities, including one American Indian population, and were randomized to receive either chlorhexidine or a placebo treatment. The primary outcome is the net caries increment (including non-cavitated lesions) from baseline to 13 months of follow-up. A cost-effectiveness analysis also will be considered.

Discussion

This new dental treatment, if efficacious and approved for use by the Food and Drug Administration (FDA), would become a new in-office, anti-microbial agent for the prevention of adult caries in the United States.

Trial Registration Number

NCT00357877  相似文献   
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Objectives: To assess the influence of clinical status on the association between total plasma bilirubin and unbound bilirubin on death or adverse neurodevelopmental outcomes at 18–22 months corrected age in extremely low birth weight infants. Method: Total plasma bilirubin and unbound bilirubin were measured in 1101 extremely low birth weight infants at 5 ± 1 days of age. Clinical criteria were used to classify infants as clinically stable or unstable. Survivors were examined at 18–22 months corrected age by certified examiners. Outcome variables were death or neurodevelopmental impairment, death or cerebral palsy, death or hearing loss, and death prior to follow‐up. For all outcomes, the interaction between bilirubin variables and clinical status was assessed in logistic regression analyses adjusted for multiple risk factors. Results: Regardless of clinical status, an increasing level of unbound bilirubin was associated with higher rates of death or neurodevelopmental impairment, death or cerebral palsy, death or hearing loss and death before follow‐up. Total plasma bilirubin values were directly associated with death or neurodevelopmental impairment, death or cerebral palsy, death or hearing loss, and death before follow‐up in unstable infants, but not in stable infants. An inverse association between total plasma bilirubin and death or cerebral palsy was found in stable infants. Conclusions: In extremely low birth weight infants, clinical status at 5 days of age affects the association between total plasma bilirubin and death or adverse neurodevelopmental outcomes at 18–22 months of corrected age. An increasing level of UB is associated a higher risk of death or adverse neurodevelopmental outcomes regardless of clinical status. Increasing levels of total plasma bilirubin are directly associated with increasing risk of death or adverse neurodevelopmental outcomes in unstable, but not in stable infants.  相似文献   
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BACKGROUND: The combination of genetic susceptibility and environmental factors induce allergic sensitization and subsequently local inflammation, resulting in atopic manifestations. OBJECTIVE: To examine whether immunological features reflecting sensitization (total and specific IgE levels, allergen-induced proliferative responses and skin tests) and markers of inflammation (plasma sE-selectin and blood eosinophils) are related to the clinical expression of atopy and whether they precede atopic disease in children up to 2 years of age. METHODS: The development of these markers during the first 2 years of life was studied prospectively in 133 newborns at high risk to develop atopic disease. RESULTS: The prevalence of atopic disease increased from 25% at 12 months to 32% at 24 months of age. The children with food allergy at 12 months, who all had atopic dermatitis (AD), turned out to have asthma-like disease in 40% and AD in 100% at the age of 24 months. Total IgE levels increased with time and from 12 months onward levels started to differ markedly between atopics and nonatopics. Food-specific IgE antibodies were significantly associated with AD (relative risk [RR] = 2.39), food (RR = 1.32) and upper-airway allergy (RR = 1.20), and house dust mite-specific IgE antibodies with upper-airway allergy (RR = 5.00). A positive skin test was significantly associated with AD (RR = 2.90) and food allergy (RR = 1.36). The inflammation markers investigated, were not related to the clinical expression or preceded atopic disease at 2 years of age in high-risk children. CONCLUSION: Positive skin tests and specific IgE to food or inhalant allergens were related to the clinical expression of different atopic diseases. The combination of AD and food allergy at 12 months reflected the strongest risk factor in this high risk cohort for the development of asthma-like disease at 24 months of age.  相似文献   
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A 59-year-old white woman with temporal arteritis developed progressive renal failure. Renal biopsy results showed focal and segmental necrotizing glomerulonephritis; furthermore, giant cells were present in the destructed vessel walls. Immunosuppressive therapy did not prevent terminal renal failure. This case shows that renal involvement may be a feature of temporal arteritis.  相似文献   
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