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Introduction: Early childhood caries (ECC) is a complex oral disease that is prevalent in US children., Objectives: The purpose of this 2-y prospective cohort study was to examine baseline and time-dependent risk factors for ECC onset in initially caries-free preschool children., Methods: A cohort of 189 initially caries-free children aged 1 to 3 y was recruited. At each 6-mo study visit, children were examined using the ICDAS index; salivary samples were collected to assess mutans streptococci (MS), lactobacilli, Candida species, salivary cortisol (prior and after a stressor), and salivary IgA. Diet and oral health behavior were assessed from parent report. Child and family stress exposure was assessed from measures of psychological symptoms, stressful life event exposure, family organization and violence exposure, and social support. Sociodemographic factors were also considered. A Kaplan-Meier estimator of survival function of time to ECC and a Cox proportional hazards model were used to identify predictors of ECC onset., Results: Onset of ECC was associated with high salivary MS levels at baseline (log-rank test, P < 0.0001). Cox proportional hazards regression showed that the risk of dental caries significantly increased with salivary MS in log scale over the 6-mo period (hazard ratio, 1.08; P = 0.01). Other risk factors in the model did not reach statistical significance., Conclusion: Our results provide prospective evidence that an increase in salivary MS predicts ECC onset in young, initially caries-free children, confirming that a high salivary MS count likely plays a causal role in ECC onset, independent of covariates., Knowledge Transfer Statement: These results suggest that we must focus on reducing salivary MS counts in young children and preventing or delaying MS colonization in infants and young children determined to be at risk for ECC.

Emerging evidence suggests that women living with HIV (WLWH) may experience higher rates of anxiety than men living with HIV and women living without HIV. To date, relatively little knowledge exists on valid anxiety screening and diagnostic tools and how they are used among WLWH, specifically WLWH of reproductive age. Thus, the purpose of this scoping review was to describe what is known in the published literature about anxiety among WLWH and the tools used to measure and screen for anxiety in clinical and research contexts. The Arksey and O'Malley methodological framework was used to guide a scoping review of published articles in PsycINFO, Scopus, Sociological Abstracts, and PubMed databases. Twenty-one measures of anxiety were used across the 52 articles identified in the search. Most measures used were self-report. Inconsistencies in standardized screening tools and cutoff scores were observed across studies. Further, measures to assess anxiety varied among studies focused on WLWH. Based on the results from this review, there is a need for consistent, valid measures of anxiety to advance research and clinical practice to support the well-being of WLWH., (© 2023. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Background: Digital droplet PCR (ddPCR) is a relatively new technique used to detect molecular alterations with unprecedented precision and accuracy. It is particularly useful for detecting point mutations and copy number variation (CNV) in samples with small amounts of target DNA. This proof of principle study was conducted to see if ddPCR technology could be applied to cytology specimens to detect molecular alterations which may influence diagnostic decision making., Methods: A range of cytological specimens derived from bladder or pancreaticobiliary origin, with varying diagnoses but with an emphasis on abnormality, underwent ddPCR testing. DNA was manually extracted from Thinprep vials, cell blocks or direct fine needle aspiration smears. ddPCR was performed using two somatic point mutations TP53 R248W and TP53 R273H assays for both urine and pancreaticobiliary cytology specimens. Three CNV assays; CDKN2A, E2F3 and YWHAZ were applied to urine samples. SMAD4 and CDKN2A CNVs were applied to the pancreaticobiliary samples., Results: 16 of 21 urine specimens showed molecular alterations using ddPCR testing. 12 of those 16 cases were associated with malignant outcomes. The pancreaticobiliary specimens showed 14 of 37 specimens with molecular alterations, all of which were associated with carcinoma. We demonstrated an increasing percentage of molecular aberrations associated with increasing severity of cytological results., Conclusion: Our results have shown that ddPCR can identify both mutations and CNVs in urine and pancreaticobiliary cytology derived samples. Being able to detect these molecular alterations may reduce the number of equivocal results leading to more timely and informed patient management decisions., (© 2023 Commonwealth of Australia. Diagnostic Cytopathology © 2023 Wiley Periodicals LLC.)

Background: There is limited literature comparing the publications on ankle arthrodesis (AA) and total ankle arthroplasty (TAA) in the setting of hemophilic arthropathy. Our objective is to systematically review the existing literature and to assess ankle arthroplasty as an alternative to ankle arthrodesis in this patient population., Methods: This systematic review was conducted and presented according to the PRISMA statement standards. A search was conducted on March 7-10, 2023, using MEDLINE (via PubMed), Embase, Scopus, ClinicalTrials.gov, CINAHL Plus with Full Text, and the Cochrane Central Register of Controlled Studies. This search was restricted to full-text human studies published in English, and articles were screened by 2 masked reviewers. Systematic reviews, case reports with less than 3 subjects, letters to the editor, and conference abstracts were excluded. Two independent reviewers rated study quality using the MINORS tool., Results: Twenty-one of 1226 studies were included in this review. Thirteen articles reviewed the outcomes associated with AA in hemophilic arthropathy whereas 10 reviewed the outcomes associated with TAA. Two of our studies were comparative and reviewed the outcomes of both AA and TAA. Additionally, 3 included studies were prospective. Studies showed that the degree of improvement in American Orthopaedic Foot & Ankle Society hindfoot-ankle score, visual analog scale pain scores, and the mental and physical component summary scores of the 36-Item Short Form Health Survey were similar for both surgeries. Complication rates were also similar between the 2 surgeries. Additionally, studies showed a significant improvement in ROM after TAA., Conclusion: Although the level of evidence in this review varies and results should be interpreted with caution, the current literature suggests similar clinical outcomes and complication rates between TAA and AA in this patient population.

Purpose: Optimal postoperative pain management remains a significant problem despite the availability of multiple preoperative, intraoperative, and postoperative pain management interventions. Recent studies suggest that racialized minorities, female sex, and individuals of lower socioeconomic status (SES) are more likely to experience more severe pain and inadequate pain management postoperatively. Our systematic review aimed to determine race, sex, and SES differences in postoperative pain and postoperative pain management., Design: This study is a systematic review of literature., Methods: Using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) methodology, we systematically searched 5 databases: Cumulative Index to Nursing and Allied Health Literature (CINAHL), PubMed, Embase, Scopus, and Cochrane. We included primary source peer-reviewed articles published after 1990 that measured postoperative pain and race/ethnicity, sex/gender, or SES, which were published in English. Two pairs of reviewers independently screened each title, abstract, and article for inclusion. In cases of disagreement, a third reviewer broke the tie., Findings: A total of 464 articles were screened, of which 32 were included in this study. In most studies, Blacks/African American experience more severe postoperative pain than Whites/Caucasians. Whites were more likely to be prescribed opioids for pain management than Blacks, Hispanics, and Asians. Also, individuals of lower SES and females reported more postoperative pain. One study found no race/ethnic group differences in pain scores and opioid use after the implementation of the enhanced recovery after surgery (ERAS) protocol., Conclusions: Optimal postoperative pain relief continues to be a challenge for individuals who self-identify as racialized minorities, females, and those of lower SES. Standardization of care may help reduce disparities in postoperative pain management., (Copyright © 2022 American Society of PeriAnesthesia Nurses. Published by Elsevier Inc. All rights reserved.)

Nearly 30-50% of people living with HIV experience HIV-Associated Neurocognitive Disorder (HAND). HAND indicates performance at least one standard deviation below the normative mean on any two cognitive domains. This method for diagnosing or classifying cognitive impairment has utility, however, cognitive intraindividual variability provides a different way to understand cognitive impairment. Cognitive intraindividual variability refers to the scatter in cognitive performance within repeated measures of the same cognitive test (i.e., inconsistency) or across different cognitive tests (i.e., dispersion). Cognitive intraindividual variability is associated with cognitive impairment and cognitive decline in various clinical populations. This integrative review of 13 articles examined two types of cognitive intraindividual variability in people living with HIV, inconsistency and dispersion. Cognitive intraindividual variability appears to be a promising approach to detect subtle cognitive impairments that are not captured by traditional mean-based neuropsychological testing. Greater intraindividual variability in people living with HIV has been associated with: 1) poorer cognitive performance and cognitive decline, 2) cortical atrophy, both gray and white matter volume, 3) poorer everyday functioning (i.e., driving simulation performance), specifically medication adherence, and 4) even mortality. This inspires future directions for research. First, greater cognitive intraindividual variability may reflect a greater task demand on executive control to harness and regulate cognitive control over time. By improving executive functioning through cognitive training, it may reduce cognitive intraindividual variability which could slow down cognitive decline. Second, cognitive intraindividual variability may be reconsidered in prior cognitive intervention studies in which only mean-based cognitive outcomes were used. It is possible that such cognitive interventions may actually improve cognitive intraindividual variability, which could have clinical relevance., (© 2021. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Hygge is a Nordic practice and mindset of creating warmth and comfort from within to improve one's wellness. Hygge has not been explored well in the scientific literature, especially in the context of a chronic illness. This article describes the experiences of an adult woman with cystic fibrosis, a progressive, incurable genetic disease primarily affecting the respiratory and gastrointestinal tracts, as she uses hygge to cope with the daily challenges of her illness. She also uses hygge as a framework for an online support group she founded to encourage other women with CF in their quest for optimal physical and emotional health. Hygge offers practical self-care behaviors that have the potential to make positive impacts on quality of life across healthy communities and those with chronic conditions, especially in the current setting of a global pandemic., (© Copyright 2022 Creative Health Care Management.)

Background: An understanding of nurse well-being remains elusive, particularly in the current toxic health care environment. Therefore, a conceptual definition of nurse well-being is needed., Purpose: The purpose of this paper is to report results of a concept analysis of nurse well-being., Methods: Rodgers' Evolutionary Method of concept analysis was used to examine the attributes, antecedents, consequences, and related concepts of nurse well-being., Findings: Findings revealed varying levels of nurse well-being: individual, organizational and community. Individual attributes included happiness, satisfaction, optimism, compassion, gratitude, forgiveness, and sound body/spirit. Organizational/community attributes included teamwork, sense of mission, pride in work, and social integration. Antecedents reflected commonalities with Maslow's hierarchy of needs, ranging from basic human needs to self-actualization. Consequences included resilience, collegial relationships, continued growth and development, empowerment, purposeful work, and physical/mental health., Discussion: Standardized definitions of individual and organizational/community nurse well-being should guide future research and policy development. Organizations must build capacity for nurses' well-being and explore its connection to patient safety and quality outcomes., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Introduction: Early childhood caries (ECC) is a complex, multifactorial oral disease that is a major public health concern because it is prevalent, profoundly alters a child's quality of life, is difficult to treat effectively, and has a distressing tendency to recur following treatment., Objectives: The purpose of the study was to examine social, psychological, and behavioral predictors of salivary bacteria and yeast in young children at risk for ECC., Methods: A sample of 189 initially caries-free preschool children was assessed for child stress physiology from salivary cortisol, child and family stress exposure, diet, oral health behaviors, and sociodemographic risks. Multiple logistic regression analysis was implemented to examine the associations between these risk factors and cariogenic microorganisms: mutans streptococci (MS), lactobacilli (LB), and Candida species., Results: Higher baseline salivary cortisol (odds ratio [OR] = 6.26; 95% confidence level [CL], 1.69-23.16) and a blunted response to an acute laboratory stressor (OR = .56; 95% CL, .37-.83) were associated with an increased likelihood of elevated salivary MS (≥10 5 colony-forming units/mL) in caries-free children. Sociodemographic risk for cariogenic microorganisms was also found. Specifically, lower education attainment of the parent/primary caregiver was associated with children being more likely to carry salivary Candida species and elevated salivary MS; in addition, children from households with an unemployed parent/primary caregiver were more likely (OR = 3.13; 95% CL, 1.2-8.05) to carry salivary Candida species and more likely (OR = 3.03; 95% CL, 1.25-7.33) to carry elevated levels of MS and/or salivary Candida and/or LB., Conclusions: The impact of sociodemographic risk and stress physiology on cariogenic disease processes are evident prior to ECC onset. The findings provide novel data on the early onset of cariogenic processes in children and the importance of considering sociodemographic, psychosocial, and behavioral factors when judging ECC risk., Knowledge Transfer Statement: The findings provide valuable and novel findings that, pre-ECC onset, the caries disease process is explicable from a detailed assessment of behavioral, sociodemographic, and psychosocial stress variables.

Background: Lutein (L), zeaxanthin (Z), and meso-zeaxanthin (MZ) are collectively called macular pigment. MZ can be converted from L in the macula. In the recent decade, many studies have been performed to investigate the effects for taking carotenoids, especially L and Z or L, Z, and MZ, as diet supplements on human health., Objective: We examined if diet supplements of L + Z or L + Z + MZ have effects on cognitive function in adults., Methods: A systemic literature search was performed in March 2021 with the following keywords: lutein, zeaxanthin, meso-zeaxanthin, cognition, cognitive, and macular pigment. The searched databases included Medline EBSCOhost, Scopus, Elsevier, Cochrane Library, ProQuest, and ClinicalTrials.gov. Findings from eight clinical trials were presented as the strongest evidence on the studied topic., Results: Most studies have found that macular pigments (L + Z) in blood or macula are positively correlated with cognitive performance. As an index of the amount of macular pigments in the brain, macular pigment optical density is related to cognitive performance in adults. In addition, there is an inverse relationship between a higher amount of macular pigment in the blood and lower risk of mild cognitive impairments or Alzheimer's disease. Based on the findings from the clinical trials, diet supplements of L + Z or L + Z + MZ are associated with improved cognition in adults., Conclusion: The diet supplements of L + Z or L + Z+MZ are associated with better cognitive functioning, which may be via their beneficial effects on the vision.

Introduction: Older adults are more susceptible to a common respiratory infection: pneumonia. Nearly 1 million older adults per year are hospitalized for community-acquired pneumonia in the United States., Objective: To examine whether wearing removable dentures are associated with an increased risk of pneumonia incidence in a geriatric population., Methods: We conducted a retrospective cohort study among patients >65 y of age within a large academic health system (University of Rochester Medical Center). The medical and dental electronic records from 2010 to 2018 were reviewed and used for data collection. The exposure was removable denture wearing. The main outcome variables were the incidence of pneumonia and time to event of pneumonia. A Cox proportional hazards regression was used to examine the association between pneumonia onset and wearing removable dentures, adjusting for demographics, socioeconomic status, and medical and dental conditions., Results: A total of 2,364 patients were included, with 1,189 (50.29%) in the denture-wearing group and 1,175 (49.70%) in the non-denture wearing group. The annual pneumonia incidence rate per 100,000 persons was 1,191 in the denture-wearing group and 128 per 100,000 persons in the non-denture wearing group, with a crude incidence rate ratio of 9.33 (95% CI, 5.41 to 18.81; P < 0.0001). The mean ± SD age of the pneumonia onset was 78.0 ± 10.0 and 78.6 ± 9.0 y among denture-wearing and nonwearing groups ( P = 0.84). The time to event of pneumonia was associated with removable denture wearing (yes/no; hazard ratio, 7.68 [95% CI, 3.91 to 15.08]; P < 0.001) after adjusting for covariates., Conclusions: Wearing removable dentures was found to be a risk predictor for pneumonia incidence among the geriatric population even after accounting for other risk factors., Knowledge Transfer Statement: Wearing removable dentures was found to be a risk predictor of pneumonia incidence among older adults. Although the current study does not imply a causal relationship between denture wearing and pneumonia, clinicians and older patients could reference the study results when choosing dental prostheses to restore missing teeth.

Background: Global demand for standardized assessment of training needs and evaluation of professional continuing education programs across the healthcare workforce has led to various instrumentation efforts. The Hennessy-Hicks Training Needs Analysis (TNA) questionnaire is one of the most widely used validated tools. Endorsed by the World Health Organization, the tool informs the creation of tailored training to meet professional development needs. The purpose of this project was to describe TNA tool utilization across the globe and critically appraise the evidence of its impact in continuous professional development across disciplines and settings., Methods: A systematic integrative literature review of the state of the evidence across PubMed, Scopus, CINAHL, and Google Scholar databases was carried out. Full-text, peer reviewed articles and published dissertations/theses in English language that utilized the original, adapted or translated version of the TNA tool were included. Selected articles were appraised for type and level of evidence., Results: A total of 33 articles were synthesized using an inductive thematic approach, which revealed three overarching themes: individual, team/interprofessional, and organizational level training needs. Included articles represented 18 countries, with more than two thirds involving high-income countries, and one third middle-income countries. Four studies (12.1%) used the original English version instrument, 23 (69.7%) adapted the original version, and 6 (18.2%) translated and culturally adapted the tool. Twenty-three studies targeted needs at the individual level and utilized TNA to determine job roles and responsibilities. Thirteen articles represented the team/interprofessional theme, applying the TNA tool to compare training needs and perceptions among professional groups. Last, three articles used the tool to monitor the quality of care across an institution or healthcare system, demonstrating the organizational training needs theme., Conclusions: Overall evidence shows that the TNA survey is widely used as a clinical practice and educational quality improvement tool across continents. Translation, cultural adaptation, and psychometric testing within a variety of settings, populations, and countries consistently reveals training gaps and outcomes of targeted continuous professional development. Furthermore, it facilitates prioritization and allocation of limited educational resources based on the identified training needs. The TNA tool effectively addresses the "know-do" gap in global human resources for health by translating knowledge into action.

Streptococcus mutans is a well-known cause of dental caries, due to its acidogenicity, aciduricity, and ability to synthesize exopolysaccharides in dental plaques. Intriguingly, not all children who carry S. mutans manifest caries, even with similar characteristics in oral hygiene, diet, and other environmental factors. This phenomenon suggests that host susceptibility potentially plays a role in the development of dental caries; however, the association between host genetics, S. mutans, and dental caries remains unclear. Therefore, this study examined the influence of host gene-by-S. mutans interaction on dental caries. Genome-wide association analyses were conducted in 709 US children (<13 years old), using the dbGap database acquired from the center for oral health research in appalachia (COHRA) and the Iowa Head Start programmes (GEIRS). A generalized estimating equation was used to examine the gene-by-S. mutans interaction effects on the outcomes (decayed and missing/filled primary teeth due to caries). Sequentially, the COHRA and GEIRS data were used to identify potential interactions and replicate the findings. Three loci at the genes interleukin 32 (IL32), galactokinase 2 (GALK2), and CUGBP, Elav-like family member 4 (CELF4) were linked to S. mutans carriage, and there was a severity of caries at a suggestive significance level among COHRA children (P < 9 × 10 -5 ), and at a nominal significance level among GEIRS children (P = 0.047-0.001). The genetic risk score that combined the three loci also significantly interacted with S. mutans (P < 0.000 1). Functional analyses indicated that the identified genes are involved in the host immune response, galactose carbohydrate metabolism, and food-rewarding system, which could potentially be used to identify children at high risk for caries and to develop personalized caries prevention strategies.

Oral Candida albicans has been detected in children with early childhood caries (ECC) and has demonstrated cariogenic traits in animal models of the disease. Conversely, other studies found no positive correlation between C. albicans and caries experience in children, while suggesting it may have protective effects as a commensal organism. Thus, this study aimed to examine whether oral C. albicans is associated with ECC. Seven electronic databases were searched. The data from eligible studies were extracted, and the risk of bias was evaluated. A fixed effects model (Mantel-Haenszel estimate) was used for meta-analysis, and the summary effect measure was calculated by odds ratio (OR) and 95% confidence interval (CI). Fifteen cross-sectional studies were included for the qualitative assessment and 9 studies for meta-analysis. Twelve studies revealed higher oral C. albicans prevalence in ECC children than in caries-free children, while 2 studies indicated an equivalent prevalence. A pooled estimate, with OR = 6.51 and 95% CI = 4.94-8.57, indicated a significantly higher ECC experience in children with oral C. albicans than those without C. albicans (p < 0.01). The odds of experiencing ECC in children with C. albicans versus children without C. albicans were 5.26 for salivary, 6.69 for plaque, and 6.3 for oral swab samples. This systematic review indicates that children with oral C. albicans have >5 times higher odds of having ECC compared to those without C. albicans. Further prospective cohort studies are needed to determine whether C. albicans could be a risk factor for ECC, and whether it is dependent on different sample sources (saliva/plaque)., (© 2017 S. Karger AG, Basel.)

Characterization and quantification of tumour clonal populations over time via longitudinal sampling are essential components in understanding and predicting the response to therapeutic interventions. Computational methods for inferring tumour clonal composition from deep-targeted sequencing data are ubiquitous, however due to the lack of a ground truth biological data, evaluating their performance is difficult. In this work, we generate a benchmark data set that simulates tumour longitudinal growth and heterogeneity by in vitro mixing of cancer cell lines with known proportions. We apply four different algorithms to our ground truth data set and assess their performance in inferring clonal composition using different metrics. We also analyse the performance of these algorithms on breast tumour xenograft samples. We conclude that methods that can simultaneously analyse multiple samples while accounting for copy number alterations as a factor in allelic measurements exhibit the most accurate predictions. These results will inform future functional genomics oriented studies of model systems where time series measurements in the context of therapeutic interventions are becoming increasingly common. These studies will need computational models which accurately reflect the multi-factorial nature of allele measurement in cancer including, as we show here, segmental aneuploidies.

Unlabelled: Recent cross-sectional studies suggest that reduced ability to generate alkali via the urease pathway in dental plaque may be an important caries risk factor, but it has not been assessed prospectively., Objective: To evaluate the effect of plaque and saliva urease activity on the risk for developing new caries over a three-year period in children., Methods: A panel of 80 children, three to six years of age at recruitment, was followed prospectively for three years. Plaque urease activity, saliva urease activity and dental caries were measured every six months. Survival analysis methodology was used to evaluate the effect of urease on caries development during the study period adjusted for gender, age, baseline caries levels, sugar consumption, amount of plaque, and mutans streptococci levels., Results: The risk for developing new caries increased in a dose-responsive manner with increasing levels of urease activity in saliva (adjusted HR(Q4 vs. Q1): 4.98; 95% CI: 1.33, 18.69) and with decreasing urease activity in plaque (adjusted HR(Q4 vs. Q1): 0.29; 95% CI: 0.11, 0.76). Multiple measurements of urease activity were conducted to overcome the variability of urease activity in this study. Baseline caries and mutans streptococci in saliva were also important predictors of caries risk., Conclusions: Increased urease activity in saliva can be an indicator of increased caries risk in children, whilst increased urease activity in plaque may be associated with reduced caries risk. The reproducibility of urease measurements must be improved before these findings can be further tested and clinically applied., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

Unlabelled: Bacterial urease activity in dental plaque and in saliva generates ammonia, which can increase the plaque pH and can protect acid-sensitive oral bacteria. Recent cross-sectional studies suggest that reduced ability to generate ammonia from urea in dental plaque can be an important caries risk factor. In spite of this proposed important clinical role, there is currently no information available regarding important clinical aspects of oral ureolysis in children., Objective: The objective of this study was to evaluate the distribution and pattern of urease activity in the dental plaque and in the saliva of children during a three-year period, and to examine the relationship of urease with some important caries risk factors., Methods: A longitudinal study was conducted with repeated measures over a three-year period on a panel of 80 children, aged 3-6 years at recruitment. The dynamics of change in urease activity were described and associated with clinical, biological, and behavioural caries risk factors., Results: Urease activity in plaque showed a trend to remain stable during the study period and was negatively associated with sugar consumption (P<0.05). Urease activity in unstimulated saliva increased with age, and it was positively associated with the levels of mutans streptococci in saliva and with the educational level of the parents (P<0.05)., Conclusions: The results of this study reveal interesting and complex interactions between oral urease activity and some important caries risk factors. Urease activity in saliva could be an indicator of mutans infection in children., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

Objectives: This investigational study assessed the suppressive effect of 10 percent povidone iodine (PI) coupled with elimination of active carious lesions on salivary mutans streptococci (MS) populations in children with severe early childhood caries (S-ECC)., Methods: 77 children (38 females, 39 males) were treated for S- ECC in one session; a 0.2 ml PI solution was applied to the dentition after dental surgery was completed and immediately wiped off. The subjects aged from 2 to 5 years (mean = 3.78 years) at baseline. Whole nonstimulated saliva samples were obtained at baseline, 30 days, 60 days, and 90 days post dental surgery. Samples were placed on ice and processed within 2 hours. The MS level in each sample was expressed as colony forming units (CFUs) per ml of saliva., Results: Approximately 50 percent of subjects had a >95 percent reduction in CFU/ml of saliva at each time point after baseline. The percentages of subjects with a >50 percent reduction in MS level were 85 percent at 30 days, 83 percent at 60 days, 84 percent at 90 days. The median (25th, 75th percentiles) CFUs/ml of saliva counts were 8.40 x 10(5) (1.49 x 10(5), 5.00 x 10(6)) at baseline (n= 77), 4.12 x 10(4) (8.40 x 10(3), 1.89 x 10(5)) at 30 days (n = 74), 4.62 x 10(4) (7.00 x 10(3), 1.36 x 10(5)) at 60 days (n = 70), and 5.09 x 10(4) (1.16 x 10(4), 1.00 x 10(5)) at 90 days (n = 70). The changes from baseline to 30 days, 60 days, and 90 days were statistically significant (P < 0.0001)., Conclusions: PI coupled with dental surgery has a significant suppressive effect on salivary MS levels in the setting of S-ECC for at least 90 days. These data strongly suggest that treatment with PI may be an important adjunct to dental surgery for S-ECC.

Aim: To assess the relationship between clinical outcomes for children treated for Early Childhood Caries (ECC) and salivary mutans streptococci (MS) levels., Study Design and Methods: The study cohort consisted of 79 children (42 males, 37 females) treated for ECC, aged from 2.3 to 7.3 years at time of entry. Whole non-stimulated saliva samples were obtained from each subject prior to dental surgery and at 6 mths post dental surgery, by saturating a cotton swab in the saliva pooled in the floor of the mouth. Samples were placed into PBS on ice and processed within 2 hours. Samples were sonicated, serially diluted and plated onto MSB and SBA agar plates, then incubated 48 hours anaerobically; SBA plates were incubated an additional 24 hours aerobically. The MS level in each sample was expressed as a percentage of the total cultivable flora. The cohort was evaluated for new caries lesions at 6 months post dental surgery. Relapse was defined as the presence of new smooth surface caries lesions., Statistics: Comparisons between Relapse (R) and Non-Relapse (NR) groups with respect to mutans streptococci levels were performed using Wilcoxon tests. Within group comparisons were performed using Wilcoxon signed-rank tests., Results: 57 children (72%) returned for the 6 months examination and 21 of these subjects (37%) relapsed. No statistically significant difference in median salivary MS levels existed between the R (0.20%) and NR (0.033%) groups at baseline (p=0.647) or at 6 months post dental surgery (R=0.03%; NR=0.01%; p=0.273). A statistically significant difference between baseline and 6 months post dental surgery was noted in the median salivary MS level within the R group (p=0.0007) and within the NR group (P<0.0001)., Conclusions: The relapse rate (37%) was high and rapid for children treated for ECC. Dental surgery resulted in a statistically significant reduction in salivary MS reservoirs for children treated for ECC. However, this did not translate into acceptable clinical outcomes.

Aim: To assess the relationship between clinical outcomes for children treated for ECC and health locus of control., Study Design and Methods: The study cohort consisted of 79 children (42 males, 37 females) treated for ECC; age range was 2.3-7.3 years (mean 4.2 years) at the time of entry into the study. A questionnaire [developed by DeVellis et al., 1993] was administered to each child's parent(s) on the day of dental surgery. This questionnaire examined the expectation that healthcare outcomes in children are influenced by one of the following loci of control: Professional, Parent, Child, Media, Fate and Divine. The cohort was evaluated for new caries lesions at 6 months post dental surgery. Relapse was defined as the presence of new smooth surface caries lesions., Statistics: For each locus, the scores for the Relapse versus Non-relapse groups (returning patients) and the scores for the returning versus non-returning patients were compared using t-tests., Results: 57 children (72%) returned for follow-up and 21 of these 57 (37%) relapsed. No statistically significant difference for Relapse versus Non-relapse groups was indicated with respect to the scores for any locus parameter (p values ranged from 0.35 to 0.95). Returning parents (N=57) versus non- returning parents (N=22) exhibited statistically significant differences with respect to the Parent, Divine and Fate loci. Returning parents exhibited higher scores on the Parent locus (p=0.0392) and lower scores on the Fate (p=0.0024) and Divine (p=0.0031) loci., Conclusion: 1). The relapse rate (37%) was high and rapid for children treated for ECC; 2). no meaningful difference existed between the Relapse versus Non-relapse groups with respect to each health locus of control parameter; 3). parents who returned for follow-up care appeared to have an internal health locus of control while those who did not return had an external locus.

Cross-linked hemoglobin (alphaalpha-Hb) may be a useful red blood cell substitute if it can be administered safely. However, cell-free hemoglobin has inherent properties that may cause oxidant-mediated toxicity. We investigated whether alphaalpha-Hb induces oxidative or inflammatory responses that lead to liver damage. alphaalpha-Hb (0.5 or 1.0 gm/kg) was infused into rats, and indices of liver injury, inflammation, and oxidative stress were examined. Although focal hepatic necrosis was noted at 24 hours, plasma alanine aminotransferase activity was not increased and lesions were resolved by 48 hours. Modest neutrophil accumulation in hepatic vessels, but not sinusoids, occurred at 24 hours. Heme oxygenase-1 (HO-1) protein and activity were induced in a dose- and time-dependent manner, with maximal induction at 24 hours. Plasma tumor necrosis factor-alpha levels were not significantly increased. Additional cytokine- and oxidant-mediated events such as nuclear transcription factor-kappaB activation and nitric oxide synthase induction were not observed. These results suggest that alphaalpha-Hb-derived products such as heme and ferric iron (Fe3+), potent inducers of HO-1, are responsible for increasing HO-1. HO-1 induction may be a protective response by the liver to metabolize excess heme and Fe3+, thereby providing antioxidative products to counter the potentially damaging oxidants produced by Fe3+-catalyzed reactions.

Purpose: Intraoral fluoride-releasing (IFR) devices provide elevated levels of fluoride in the mouth for extended periods of time. However, retention and protection of the devices have posed major challenges for clinical applications. The objectives of this study were to develop new methods for retaining and protecting IFR devices in the mouth and to assess their effects on salivary fluoride levels and distribution in adolescents., Methods: Four different IFR systems (combinations of an IFR device and its retainer) were evaluated in four groups of 10 adolescents each, 12-15 years of age, for a period of six months. Each child wore two IFR systems of a given type affixed to the buccal surface of each permanent maxillary first molar. Unstimulated saliva samples were collected at each clinical examination and analyzed for fluoride., Results: A significant increase in salivary fluoride concentration from a baseline mean of 0.07-0.69 microgram/mL was observed on day 14 postinsertion. IFR system retention was 85% after 6 months and, of the systems retained, 100% were functional., Conclusions: These findings suggest that IFR devices can be successfully protected and retained in the mouth for prolonged periods of time.

This study did follow-up examinations of 84 Medicaid-eligible children with nursing caries after they received treatment for nursing caries utilizing general anesthesia. Results at six months suggest that parents are unresponsive to follow-up care and over half of the children seen had new smooth surface caries lesions. While results are preliminary, they suggest that major changes are needed in the tertiary care of children with nursing caries.

Regulation of induced nitric oxide synthase (NOS) in isolated rat hepatocytes is poorly understood. The specific protein tyrosine kinase inhibitor genistein was used to determine if NOS induction is dependent on protein tyrosine kinase activation. Genistein inhibited tumor necrosis factor-alpha (TNF-alpha)-stimulated induction of NOS activity and NOS protein in a dose-dependent manner. Genistein also impaired TNF-alpha-induced NOS mRNA accumulation, suggesting protein tyrosine kinase regulation of NOS induction occurred at the level of transcription-translation. Like TNF-alpha, genistein inhibited induction of NOS protein by a second proinflammatory cytokine, interleukin-1beta, suggesting similar activation mechanisms by proinflammatory cytokines. NOS induction by other stimuli, including phorbol 12-myristate 13-acetate and the superoxide-generating system xanthine/xanthine oxidase, was also inhibited by genistein. Finally, cytokine-stimulated protein tyrosine kinase activity in hepatocytes was demonstrated by increased tyrosine phosphorylation of five high molecular mass protein bands. Genistein inhibited this cytokine-induced phosphotyrosine increase. The commonality of genistein inhibition suggests that protein tyrosine kinase activity is critical for NOS induction by a variety of stimuli.

Hepatocytes exposed to the cytokines tumor necrosis factor alpha (TNFalpha) and interferon gamma (IFNgamma), in combination with a nontoxic dose of lead (Pb), exhibited significantly greater cytotoxicity compared to cytokine-treated hepatocytes after 24 hr treatment. Concentrations of Pb which interact with the cytokines to cause cytotoxicity stimulated hepatocytes cultured at this high cell density (63,830 cells/cm2) to undergo active DNA synthesis. DNA synthesis was also observed in hepatocytes plated at a low cell densities (21,276 cells/cm2) and these cells were sensitive to the toxic effects of the cytokines in the absence of Pb. Under conditions of active DNA synthesis, induced by either Pb or cell density, cytokine-induced toxicity appeared to be the result of extensive DNA fragmentation. Both DNA fragmentation and cytotoxicity were inhibited by treatment with an antioxidant mixture. Pb potentiated cytokine-induced oxidative stress within hepatocytes as indicated by decreased intracellular glutathione (GSH) and increased efflux of oxidized glutathione (GSSG) prior to cytotoxicity. The combination of cytokines and Pb also caused a significant decline in intracellular ATP concentrations prior to the onset of cytotoxicity. ATP concentrations were not altered by treatment with Pb or cytokines alone. Pb treatment did not alter total protein synthesis within hepatocytes. These results indicate that the cytotoxic interaction between Pb and the cytokines TNFalpha and IFNgamma may be mediated by oxidative DNA damage resulting from cytokine-induced oxidative stress and stimulation of mitogenic signals.

Xerostomia is the subjective sensation of dry mouth. Estimates on the occurrence of xerostomia in community-dwelling adults have ranged from 10% among persons over age 50 to 40% for persons over age 65. Virtually no data are available for persons under age 50. To begin to establish a database on the occurrence of xerostomia and factors associated with it, a cross-sectional assessment of self-reported symptoms and salivary function was conducted across a broad age-range of generally healthy community-dwelling adults. A convenience sample of 710 adults who ranged from 19 to 88 years of age was drawn from various sources in the greater-Rochester, New York area. Study volunteers were administered a standardized questionnaire on general and oral health, which included questions on the symptoms of xerostomia, and were provided an oral screening examination, which included measurement of unstimulated and stimulated whole saliva flow rates. Overall, the observed prevalence of xerostomia was 24% among females and 18% among males. While xerostomia was more commonly observed in women than men, this association was only clear after age 50. Xerostomia was associated with: use of medications with hyposalivatory side-effects; difficulty with dry foods; cracked lips; dry eyes; difficulty swallowing; and, among males, current cigarette smoking. Results indicated a tendency for salivary flow rates to be lower for older persons, particularly the stimulated flow rate. There was a tendency in the younger cohorts for flow rates to be lower among individuals who reported sensation of dry mouth than among those who did not. This tendency was not apparent among older persons, suggesting that younger persons may be more likely to experience symptoms of oral dryness when salivary flow was low while older persons may relate symptoms of dry mouth to a more complex constellation of factors where salivary flow is only one component. These findings need to be examined further.

Induction of hepatic nitric oxide synthase (NOS) by tumor necrosis factor-alpha (TNF alpha), interleukin-1 beta (IL-1 beta), interferon-gamma (IFN gamma), interleukin-6 (IL-6), and lipopolysaccharide was assessed as activity and immunoreactive protein. Hepatic NOS activity was cytosolic and had cofactor requirements consistent with inducible nitric oxide synthase (NOS2). NOS induction by TNF alpha was dose dependent from concentrations of 0.06 to 60 nM and was increased 2-3-fold by IFN gamma. NOS induction was reflective of total TNF alpha binding to hepatocyte receptors. Hepatocyte TNF alpha binding fit a biphasic curve with high affinity (K(d) = 1.4 nM, Bmax = 3157 sites) and low affinity (K(d) = 157 nM, Bmax = 204,948 sites) elements. NOS2 activity was induced by lipopolysaccharide, IL-1 beta, TNF alpha, and IFN gamma but not by IL-6. All cytokine stimuli were inhibited by antioxidants. Oxygen radical generation was directly measured as dichlorofluoroscein fluorescence in isolated mitochondria. Mitochondria from TNF alpha-treated hepatocytes generated more oxygen radicals than did controls. Antioxidants reduced mitochondrial generation of oxygen radicals. Activation of the transcription factor nuclear factor-kappa B by TNF alpha, IFN gamma, and IL-1 beta was assessed by gel shift analysis. Cytokine treatment increased nuclear factor-kappa B binding, and the addition of antioxidants or rotenone inhibited cytokine activation. Taken together, these data suggest that oxygen radicals, possibly generated by mitochondria, play a major role in NOS2 induction by cytokines.

In 1992, a simple and sensitive assay for detecting DNA-protein crosslinks was developed [1]. In an effort to facilitate the greater use of the assay, a number of studies were conducted to evaluate its reliability and reproducibility. During this work, the assay was used to assess whether various metals and other compounds could induce crosslinks in cultured human lymphocytes (Epstein-Barr virus-transformed Burkitt's Lymphoma cell line). Potassium permanganate, mercury chloride, lead nitrate, magnesium perchlorate, aluminum chloride, and cadmium chloride did not induce DNA-protein crosslinks at either cytotoxic or non-cytotoxic levels. Copper sulfate, arsenic trioxide, and potassium chromate induced DNA-protein crosslinks only at cytotoxic concentrations. Acute lethality of the cells was assessed immediately after exposure to metals by trypan blue exclusion while long-term lethality was assessed by cell proliferation and trypan blue exclusion following an incubation period of 5 days after exposure to the metal compound. All metals exhibited more toxicity in the long-term lethality assay compared to the short-term assay. The cultured human lymphocytes treated with various doses of lead acetate, cadmium chloride, arsenic trioxide and copper sulfate, as well as cis-platinum and chromate, were sent to four different laboratories to compare the reliability and reproducibility of the DNA-protein crosslink assay. Depending on the chemical studied, there were quantitative differences in the results observed among the various laboratories using the assay. However, all laboratories generally showed that cis-platinum, chromate, arsenic trioxide and copper sulfate induced DNA-protein crosslinks at levels that produced acute cytotoxicity, whereas cadmium chloride and lead acetate did not.

We explored the effects of cytokines on cytochrome P-450 (CYP) in rat hepatocyte primary cultures. CYP content and several CYP protein levels were assessed in hepatocytes treated with a cytokine combination consisting of tumor necrosis factor-alpha (TNF-alpha), interleukin-1 beta (IL-1 beta), and interferon-gamma (IFN gamma). The combination was found to depress CYP content by 69 +/- 6%. Protein levels of CYP forms 1A2, 2C11, 2B1/2, and 3A2 were assessed with immunoblotting. Treatment with the cytokine combination resulted in a decrease in each CYP enzyme, with CYP2B1/2 exhibiting the greatest loss, to 33 +/- 9% of untreated cells. The addition of inhibitors of nitric oxide synthase (NOS) significantly prevented the cytokine-mediated decrease in each CYP protein, indicating a role for nitric oxide (NO) in the down-regulation. Treatment of hepatocytes with the NO donor 1-hydroxy-2-oxo-3,3-bis(3-aminoethyl)-1-triazene (300 microM) caused a decrease in each CYP apoprotein, with CYP2B1/2 exhibiting the greatest decrease, to 33 +/- 8% of untreated cells. Decreases in CYP protein levels were observed in response to treatment with TNF alpha, IL-1 beta, or IL-6 alone. With IL-1 beta treatment, increased levels of NO production were accompanied by decreased levels of each CYP protein. With TNF alpha treatment, increased levels of NO production were accompanied by decreased levels of CYP2B1/2 and CYP3A2. The effects of IL-1 beta and TNF alpha were blocked by the inclusion of the NOS inhibitors. Conversely, IL-6 caused a decrease in each of the CYP enzymes but did not affect NO production. The results indicate a dissociation in vitro between NOS induction and CYP down-regulation for IL-6 treatment, whereas the down-regulation of CYP by TNF alpha and IL-1 beta in vitro is directly associated with NO production.

We determined the free-amino acid content of stimulated parotid (ductal) saliva from two groups of adult subjects whose caries experiences were markedly different. The levels of free arginine and free lysine in the parotid saliva of caries-free adults were significantly higher than those found in the parotid saliva of individuals with a history of dental decay. There was no correlation, however, between the levels of these amino acids and the DMFS score within the caries-susceptible groups. Microbial catabolism of dibasic amino acids contributes to the neutralization of plaque acids and may partially account for the higher resting plaque pH observed in caries-free subjects. Alternatively, the elevations observed in free levels of arginine and lysine may reflect a systemic alteration in amino acid metabolism which is common to the caries-free group of subjects.

Regulation of induced nitric oxide synthase in rat hepatocyte primary cultures was explored. Nitric oxide synthase (NOS) induction by tumor necrosis factor-alpha (TNF alpha) is synergized by interferon-gamma, and both NOS activity and gene expression are maximal by 10 h and maintained through 24 h. Glutathione depletion by diethylmaleate, which conjugates reduced glutathione, 1,3-bis(chloroethyl)-1-nitrosourea (BCNU), a glutathione reductase inhibitor, or buthionine sulfoxamine, a glutathione synthesis inhibitor, abolishes or reduces NOS induction in TNF alpha-treated hepatocytes, whereas N-acetylcysteine has little effect. Thus, reduced glutathione is critical to NOS mRNA induction and activity in TNF alpha-treated hepatocytes. NOS induction in TNF alpha-treated cells is reduced by rotenone, a mitochondrial complex 1 inhibitor. Concurrent treatment with TNF alpha and the antioxidant, Trolox, or the iron-chelating agent, desferrioxamine, also reduces NOS activity. Dithiothreitol, a thiol antioxidant, reduced TNF alpha induction of NOS. Trolox and BCNU, combined, blocked TNF alpha stimulation of NOS greater than either agent alone. These results suggest that TNF alpha increases mitochondrial production of reactive oxygen intermediates (ROI), which contributes to NOS induction. Hepatocytes exposed to extracellular ROI generation through a xanthine/xanthine oxidase superoxide-generating system expressed increased NOS activity and mRNA levels. NOS induction by superoxide also requires reduced glutathione since diethylmaleate blocks induction by xanthine/xanthine oxidase while N-acetylcysteine elevates NOS expression. Thus, the generation of ROI by cytokines or other physiological processes stimulates the induction of NOS and this process is regulated by cellular levels of reduced glutathione.

High concentrations of tumor necrosis factor alpha (TNF alpha) are cytotoxic to cultured hepatocytes. Impairment of energy metabolism and generation of an intracellular oxidant stress are important events in the pathogenesis of this toxicity (6). In the present study, we have examined the role of phospholipase A2 activation in TNF alpha-induced toxicity in mouse hepatocytes, since it has been reported to play a key role in TNF alpha cytolytic activity in other cell types. Recombinant murine TNF alpha (0.1 microgram/mL) caused a dose-dependent increase in PLA2 activity in cultured mouse hepatocytes. The increase in PLA2 activity was observed after only 0.5 hour of exposure (152 +/- 10% of control), and continued to increased over the first 4 hours of exposure (292 +/- 32%). However, TNF alpha-induced GSSG efflux and ATP depletion did not occur until after 2 hours of exposure. Furthermore, a small level of cytotoxicity was observed after a 24 hour incubation period. Putative PLA2 inhibitors, chlorpromazine (CPZ) and 4-bromophenacyl bromide (BPB), both prevented the TNF alpha-induced increase in PLA2 activity. They also reduced ATP depletion, GSSG efflux, and cytotoxicity. The PLA2 inhibitor, manoalide (a natural marine product), completely prevented PLA2 activation and cytotoxicity induced by TNF alpha. Pretreatment of hepatocytes with cycloheximide, to inhibit protein synthesis, increased TNF alpha-induced cytotoxicity. Cycloheximide pretreatment also potentiated PLA2 activation, ATP depletion, and GSSG efflux. CPZ and BPB both reduced the extent of PLA2 activation, ATP depletion, GSSG formation, and cytotoxicity in the cycloheximide pretreated cells exposed to TNF alpha. Taken together, these results demonstrate that TNF alpha activates PLA2, which occurs prior to other deleterious events in hepatocytes, and that inhibition of PLA2 activity reduces cell injury by TNF alpha. This suggests that PLA2 activation may lead to impairment of energy metabolism, an oxidant stress, and cytotoxicity in cells exposed to TNF alpha. Additionally, protein synthesis inhibition potentiates TNF alpha induction of PLA2 and toxicity, suggesting that there is a protein-synthesis-dependent protective mechanism in hepatocytes which ameliorates the effects induced by PLA2. These findings provide strong evidence that PLA2 activation plays an important role in the pathogenesis of toxicity induced by TNF alpha in cultured mouse hepatocytes.

Recombinant murine tumor necrosis factor (TNF-alpha) was labeled with 125I and used to determine the binding characteristics, internalization and intracellular degradation in cultured mouse hepatocytes. [125I]TNF-alpha bound specifically to hepatocytes and Scatchard analysis of the data indicated binding to both a low-affinity (Kd = 20 nM) high capacity (51225 sites/cell) component and high-affinity component (Kd = 4 pM), with low capacity (290 sites/cell). The extent of TNF-alpha binding to hepatocytes correlated closely with its biological activity in hepatocytes, as indexed by depletion of intracellular ATP. At concentrations lower than 0.06 nM there was minimal binding and no effect on cellular ATP, whereas maximal binding at concentrations greater than 45 nM caused 80% depletion (in comparison to controls) of hepatocyte ATP. Incubation at 37 degrees C resulted in rapid uptake, internalization and degradation of [125I]TNF-alpha. This was followed by release of degraded material from hepatocytes. Examination, by reverse transcriptase/polymerase chain reaction technology, of hepatocyte RNA extracted after the 4-hr adherence period revealed that mouse hepatocytes expressed mRNA for both TNF-alpha receptor 1 and TNF-alpha receptor 2, and that the relative abundance of TNF-alpha receptor 1 was approximately 7-fold greater than that for TNF-alpha receptor 2. Because it has been shown that these receptors have different affinities for TNF-alpha, this may explain the high- and low-affinity binding sites present on cultured mouse hepatocytes.

A case of a homicide and an attempted homicide during presumed sleepwalking is reported in which somnambulism was the legal defense and led to an acquittal. Other possible explanations including complex partial seizures, dissociative state, rapid eye movement sleep behavior disorder and volitional waking behavior are discussed. The evidence supporting the probability that this act occurred during an episode of somnambulism and sleep-related confusional arousal is reviewed and weighed. This evidence includes personal and family history of somnambulism and related disorders; neurological, psychiatric and psychological assessments; presence of possible precipitating factors; and polysomnographic data.

Interest among researchers in the diagnosis, aetiology, prevention, and treatment of root caries has increased substantially over the past two decades. However, there are some fundamental problems impeding the advancement of the field which remain to be addressed and resolved. A universally acceptable definition of root caries is not yet available. The relationship of root caries to coronal caries has not been established. The underlying disease process is still not clearly understood. The optimal utilisation of preventive/therapeutic agents for the treatment or prevention of root caries has not been determined. New treatment materials and preventive agents have not yet been tested in controlled clinical trials. These are a few of the issues and problems which we address in this paper.

Interferon-gamma (IFN-gamma) has been shown to exacerbate tumor necrosis factor alpha (TNF alpha)-induced hepatotoxicity in vivo as well as act synergistically with TNF alpha in a variety of biological actions. In the present study we have examined interactions of IFN-gamma with TNF alpha and the role of nitric oxide synthase (NOS) activity in the generation of an intracellular oxidant stress in isolated mouse hepatocytes. Exposure to either IFN-gamma or TNF alpha significantly increased NOS activity. In combination, TNF alpha and IFN-gamma markedly increased NOS activity beyond that expected for a merely additive effect. IFN-gamma potentiated TNF alpha-induced effects on the hepatocyte glutathione pool, increasing the extent of GSH depletion and GSSG efflux. Furthermore, IFN-gamma exacerbated TNF alpha-induced ATP depletion. Exposure to both TNF alpha and IFN-gamma resulted in significant cytotoxicity in hepatocytes, whereas neither cytokine alone produced any toxicity. TNF alpha-induced cytotoxicity in hepatocytes pretreated with 1,3-bis (chloroethyl)-1-nitrosourea (BCNU, a glutathione reductase inhibitor) was potentiated by IFN-gamma. TNF alpha/IFN-gamma-induced GSSG efflux was prevented when hepatocytes were treated with the antioxidant mannitol. Furthermore, mannitol reduced the extent of ATP depletion as well as cytotoxicity induced by TNF alpha and IFN-gamma in either BCNU- or non-BCNU-treated hepatocytes. In contrast, mannitol abolished cytotoxicity in BCNU-treated cells exposed to TNF alpha alone. Thus, mannitol provides significant protection against deleterious oxidative effects induced by IFN-gamma and TNF alpha. However, IFN-gamma also appears to potentiate the deleterious effects of TNF alpha, at least in part, by mechanisms other than an increase in oxygen radical generation. Using the methylated analog of arginine, NG-monomethyl-L-arginine, to inhibit NOS activity, it was demonstrated that TNF alpha/IFN-gamma-induced ATP depletion, GSSG efflux, and cytotoxicity were not dependent upon the stimulation of NOS. Furthermore, significant increases in NOS activity did not occur until after 4 hr of exposure to either cytokine, whereas GSSG efflux and ATP depletion occurred during the first 4 hr of incubation. Taken together, these results indicate that IFN-gamma acts synergistically with TNF alpha, resulting in the potentiation of an intracellular oxidative stress, inhibition of energy metabolism, and cytotoxicity. However, these events do not appear to be related to an increase in NOS activity.

Although the prevalence of dental caries is continuing to decline, it still affects a majority of the US population and can be a serious problem for those afflicted. The objective of this project was to develop and perfect a model for assessment of risk of dental caries onset in children. In the first study, reported herein, a set of clinical, microbiological, biochemical, and socio-demographic variables was identified that distinguished, with an acceptable level of sensitivity and specificity, between children who had no previous caries experience and children who had high caries levels. A total of 313 children--age 12-15 years, 140 from a fluoridated community and 173 from a fluoride-deficient community--was selected on the basis of previous caries experience, either zero DMFS or high DMFS (> or = 6 in the fluoridated or > or = 8 in the fluoride-deficient community). Clinical exams for DMFS, dental fluorosis, and plaque were conducted. Stimulated whole saliva was collected for analysis of mutans streptococci, lactobacilli, total viable flora, and fluoride concentration. A questionnaire was used for collection of demographic data as well as information on prior fluoride exposure, dietary habits, and oral hygiene practices. By means of discriminant analyses, with use of seven key clinical and laboratory variables, it was possible for zero-DMFS subjects to e classified correctly (specificity) in 77.6% of cases in the fluoridated community and in 86.1% of cases in the fluoride-deficient community. High-caries subjects were classified as such (sensitivity) in 79.3% and 88.1% of cases, respectively.

Our objective was to develop and perfect a model for the assessment of risk of dental caries onset in children. Even though dental caries prevalence in children is continuing to decline, there is still a significant minority for whom it is a problem. In this study, we sought to ascertain whether a set of variables selected in a previous cross-sectional study could be used to differentiate between caries-free six-year-olds who would or would not subsequently present with clinically-detectable caries. A total of 472 caries-free six-year-olds--286 from a fluoridated community and 186 from a fluoride-deficient community--was selected. Clinical examinations for DMFS, dental fluorosis, and plaque were conducted. Stimulated whole saliva was collected for analysis of mutants streptococci, lactobacilli, total viable flora, and fluoride, calcium, and phosphate concentrations. A questionnaire was used for collection of demographic data as well as information on prior fluoride exposure, dietary habits, and oral hygiene practices. By means of linear discriminant analyses, it was possible to predict correctly which children would develop caries within six to 12 months (sensitivity) in 82.8% of cases and which children would not develop caries during that period (specificity) in 82.4% of cases.

Catastrophic hyposalivation significantly increases susceptibility to dental caries in dentate individuals and may cause the expression or exacerbation of other oral diseases/disorders as well. The effect of subcatastrophic hyposalivation on susceptibility to caries or other diseases/disorders is less well understood. The aim of this study (part of a larger study on the prevalence of hyposalivation) was to determine the prevalence and to measure the association of oral pathologic conditions with unstimulated and stimulated whole saliva flow rates. Only 6.3% of all study participants had significantly diminished unstimulated (< 0.05 ml/min) and stimulated (< 0.50 ml/min) saliva flow rates. A total of 15 individuals were encountered with oral pathologic lesions and none of these lesions were associated with hyposalivation. Although the prevalence of coronal caries, root surface caries, abrasion, and erosion tended to increase as salivary flow decreased, when the effect of age was considered no significant differences were present. These data suggest that low saliva flow rates alone, at least from an epidemiologic perspective, do not have a clinically relevant effect on susceptibility to oral diseases/disorders.

Tumor necrosis factor alpha (TNF alpha) is a macrophage-derived cytokine which participates in homeostatic tissue repair. It is also a potentially useful antitumor agent. Liver toxicity, however, limits TNF alpha's clinical utility and suggests that it may play a role in liver toxicity of various etiologies. To determine the direct effects of TNF alpha on hepatocytes, in the absence of infiltrating leukocytes and other inflammatory mediators, an isolated mouse hepatocyte model has been used in the present study. Hepatocytes exposed to recombinant human TNF alpha (1-10 micrograms/ml) exhibited intracellular GSH depletion and GSSG efflux during the first 2 hr of exposure, but no cytotoxicity was observed. However, TNF alpha was toxic to hepatocytes pretreated with 1,3-bis(chloroethyl)-1-nitrosourea to inhibit GSSG-reductase activity. Furthermore, these cells exhibited a greater efflux of GSSG upon exposure to TNF alpha. TNF alpha also caused a marked decrease in cellular ATP concentrations, which occurred after initiation of effects on the glutathione pool. These findings indicate that high concentrations of TNF alpha induce an oxidant stress in isolated hepatocytes. The antioxidants mannitol and benzoate, as well as the iron chelator deferoxamine, reduced the extent of TNF alpha-induced oxidant effects in hepatocytes, which indicates that the oxidant stress may involve hydroxyl radical generation. Hepatocytes treated with ruthenium red or fructose were less susceptible to TNF alpha-induced ATP depletion, which suggests that mitochondrial calcium cycling may be involved in disruption to energy metabolism.

Plaque indices, numbers of mutans streptococci, lactobacilli and total viable flora in plaque and saliva were assessed as part of a large-scale cross-sectional study designed to determine the factors that are associated with high caries activity in children. Subjects, 12 to 15 years old, residing in areas where the water supplies were either fluoridated (n = 140) or fluoride-deficient (n = 173) were studied. Mutans streptococci and lactobacilli numbers in saliva were positively correlated with plaque index. Plaque indices were significantly higher in the high-caries group than in the zero-caries group of the fluoride-deficient community. In the fluoridated community, there was no difference in the plaque index between the zero- or high-caries groups. In each community, pooled dental plaque and saliva harbored fewer mutans streptococci and lactobacilli in the zero-caries than the high-caries group. Greater numbers of mutans streptococci were found in the dental plaque and saliva of the zero-caries subjects in the fluoridated community than in the fluoride-deficient community, suggesting that a greater caries challenge can coexist with zero-caries status in the fluoridated community.

The present study was undertaken to evaluate the effect of a twice-daily topical application of a 0.05% NaF mouthrinse on de- and remineralization in the oral cavities of subjects suffering from radiation-induced hyposalivation. Six subjects each wore a bonded intra-oral appliance containing a sound and a demineralized human enamel slab for four weeks. During that period, the subjects used 0.05% NaF rinses, twice daily, instead of the 1.1% NaF gel that had previously been a part of their preventive regimen. Salivary flow rates, plaque pH profiles following a 10% sucrose rinse, S. mutans and lactobacillus counts, fluoride clearance, and enamel microhardness were determined during the study. Sound enamel samples displayed no evidence of demineralization, and the previously demineralized enamel showed remineralization in the outer 50 microns in three of the six subjects. The results suggest that a twice-daily oral rinse with 0.05% NaF can prevent demineralization and enhance remineralization in subjects with radiation-induced hyposalivation.

A triple-blind clinical study was performed to measure the amount, rate and oral distribution of fluoride released from Fluoroshield, a commercially available, filled Bis-GMA type sealant containing 2% NaF and 1% adhesion promoter. The study also compared the retention of this sealant in vivo with its nonfluoride-containing analog, Prisma-Shield. One hundred forty-seven pairs of caries-free permanent first molars in 82 children, aged six to nine years, were sealed with the two sealant types. Samples of whole unstimulated saliva, as well as site-specific saliva samples, were collected from 20 randomly selected subjects and analyzed for fluoride content. Complete or partial coverage was observed for 274 of 275 teeth evaluated at six months and for all 199 teeth evaluated at 12 months. There were no statistically significant differences in retention between the two sealants at 6 to 12 months. The release of fluoride was intense, but of short duration. Mean whole saliva fluoride content was 2.9 ppm +/- 0.13 (S.E.), and site-specific saliva fluoride content was 11.4 ppm +/- 1.02 (S.E.) buccal to the fluoride-releasing sealant at 30 minutes; both values returned to baseline within 24 hours. It was concluded that the addition and subsequent release of fluoride in Fluroshield did not decrease its retentiveness.

The metabolism of bromobenzene has been examined in isolated hepatocytes and liver microsomes from phenobarbital-induced rats and in phenobarbital-induced rats in vivo. The metabolite profile produced upon incubation of isolated rat hepatocytes with bromobenzene differed with the hepatocyte concentration. At a low hepatocyte concentration (0.5 x 10(6) cells/ml), 4-bromophenol was the major metabolite, while at higher hepatocyte concentrations (2.0 and 5.0 x 10(6) cells/ml) bromobenzene-3,4-dihydrodiol was the major metabolite. 4-Bromophenol was the primary metabolite in incubations with rat liver microsomes. In vivo, 3- and 4-bromophenol were more predominant, with very little dihydrodiol formed. 4-Bromocatechol, a potentially toxic metabolite of bromobenzene, was formed in vivo as well as in isolated hepatocytes and microsomes. However, the mechanism of catechol formation differed, as determined by the retention of a deuterium label at the para position of bromobenzene. In microsomes, 4-bromophenol was the predominant precursor metabolite of 4-bromocatechol. In isolated hepatocytes, although the relative contribution of 4-bromophenol as the bromocatechol precursor differed with hepatocyte concentration, bromobenzene-3,4-dihydrodiol was the predominant precursor at all concentrations. In vivo, as in isolated hepatocytes, 4-bromocatechol was formed primarily via bromobenzene-3,4-dihydrodiol.

Myeloperoxidase (MPO) is an enzyme found in granulocytes of neutrophils, but not in mammalian tissues. Previous studies have directly correlated MPO activity with neutrophil accumulation in tissues. This study presents a method for determining MPO activity in liver. Neutrophil accumulation in rat liver was provoked by creating partial ischemia followed by reperfusion. Liver homogenates prepared by a standard procedure showed no MPO activity. The homogenate was applied to Sephadex G100 and DEAE Sepharose CL6B columns which separated MPO activity from inhibitory activity. The inhibitor was identified as catalase based upon its elution from the columns and removal with 3-amino- 1,2,4-triazole (AT), a catalase inhibitor. Based upon these findings, it was determined that full MPO activity can be assayed in unfractionated liver homogenates by first inactivating catalase with AT.

The metabolism and toxicity of formaldehyde (CH2O) in isolated rat hepatocytes was found to be dependent upon the intracellular concentration of glutathione (GSH). Using hepatocytes depleted of GSH by treatment with diethyl maleate (DEM), the rate of CH2O (5.0 mM) disappearance was significantly decreased. Formaldehyde decreased the concentration of GSH in hepatocytes, probably by the extrusion of the CH2O-GSH adduct, S-hydroxymethylglutathione. Formaldehyde toxicity was potentiated in cells pretreated with 1.0 mM DEM as measured by the loss of membrane integrity (NADH stimulation of lactate dehydrogenase (LDH) activity) and an increase in lipid peroxidation (formation of thiobarbituric acid-reactive compounds). This potentiation of toxicity was both CH2O concentration-dependent and time-dependent. There was an excellent correlation between the increase in lipid peroxidation and the decrease in cell viability. L-Methionine (1.0 mM) both protected the cells from toxicity caused by the combination of 8.0 mM CH2O and 1.0 mM DEM and increased the cellular GSH concentration. The antioxidants, ascorbate, butylated hydroxytoluene (BHT) and alpha-tocopherol (10, 25 and 125 microM), all exhibited dose-dependent protection against toxicity produced by 8.0 mM CH2O and 1.0 mM DEM. At toxic concentrations of CH2O (10.0-13.0 mM), administered by itself, lipid peroxidation did not increase concomitantly with the decrease in cell viability and the addition of antioxidants (125 microM) did not influence CH2O toxicity. These results suggest that CH2O toxicity in GSH-depleted hepatocytes may be mediated by free radicals as a result of the effect of CH2O on a critical cellular pool of GSH. However, cells with normal concentrations of GSH are damaged by CH2O by a different mechanism.