Pilot GWAS of caries in African-Americans shows genetic heterogeneity.

BACKGROUND: Dental caries is the most common chronic disease in the US and disproportionately affects racial/ethnic minorities. Caries is heritable, and though genetic heterogeneity exists between ancestries for a substantial portion of loci associated with complex disease, a genome-wide association study (GWAS) of caries specifically in African Americans has not been performed previously. METHODS: We performed exploratory GWAS of dental caries in 109 African American adults (age > 18) and 96 children (age 3-12) from the Center for Oral Health Research in Appalachia (COHRA1 cohort). Caries phenotypes (DMFS, DMFT, dft, and dfs indices) assessed by dental exams were tested for association with 5 million genotyped or imputed single nucleotide polymorphisms (SNPs), separately in the two age groups. The GWAS was performed using linear regression with adjustment for age, sex, and two principal components of ancestry. A maximum of 1 million adaptive permutations were run to determine empirical significance. RESULTS: No loci met the threshold for genome-wide significance, though some of the strongest signals were near genes previously implicated in caries such as antimicrobial peptide DEFB1 (rs2515501; p = 4.54 × 10- 6) and TUFT1 (rs11805632; p = 5.15 × 10- 6). Effect estimates of lead SNPs at suggestive loci were compared between African Americans and Caucasians (adults N = 918; children N = 983). Significant (p < 5 × 10- 8) genetic heterogeneity for caries risk was found between racial groups for 50% of the suggestive loci in children, and 12-18% of the suggestive loci in adults. CONCLUSIONS: The genetic heterogeneity results suggest that there may be differences in the contributions of genetic variants to caries across racial groups, and highlight the critical need for the inclusion of minorities in subsequent and larger genetic studies of caries in order to meet the goals of precision medicine and to reduce oral health disparities.

Genome-wide association study of primary dentition pit-and-fissure and smooth surface caries.

Dental caries continues to be the most common chronic disease in children today. Despite the substantial involvement of genetics in the process of caries development, the specific genes contributing to dental caries remain largely unknown. We performed separate genome-wide association studies of smooth and pit-and-fissure tooth surface caries experience in the primary dentitions of self-reported white children in two samples from Iowa and rural Appalachia. In total, 1,006 children (ages 3-12 years) were included for smooth surface analysis, and 979 children (ages 4-14 years) for pit-and-fissure surface analysis. Associations were tested for more than 1.2 million single nucleotide polymorphisms, either genotyped or imputed. We detected genome-wide significant signals in KPNA4 (p value = 2.0E-9), and suggestive signals in ITGAL (p value = 2.1E-7) and PLUNC family genes (p value = 2.0E-6), thus nominating these novel loci as putative caries susceptibility genes. We also replicated associations observed in previous studies for MPPED2 (p value = 6.9E-6), AJAP1 (p value = 1.6E-6) and RPS6KA2 (p value = 7.3E-6). Replication of these associations in additional samples, as well as experimental studies to determine the biological functions of associated genetic variants, are warranted. Ultimately, efforts such as this may lead to a better understanding of caries etiology, and could eventually facilitate the development of new interventions and preventive measures.

The impact of colonization by multidrug resistant bacteria on graft survival, risk of infection, and mortality in recipients of solid organ transplant: systematic review and meta-analysis.

BACKGROUND: The Global increase in colonization by multidrug-resistant (MDR) bacteria poses a significant concern. The precise impact of MDR colonization in solid organ transplant recipients (SOTR) remains not well established. OBJECTIVES: To assess the impact of MDR colonization on SOTR's mortality, infection, or graft loss. METHODS AND DATA SOURCES: Data from PROSPERO, OVID Medline, OVID EMBASE, Wiley Cochrane Library, ProQuest Dissertations, Theses Global, and SCOPUS were systematically reviewed, spanning from inception until 20 March 2023. The study protocol was registered with PROSPERO (CRD42022290011) and followed the PRISMA guidelines. STUDY ELIGIBILITY CRITERIA, PARTICIPANTS, INTERVENTIONS, AND ASSESSMENT OF RISK OF BIAS: Cohorts and case-control studies that reported on adult SOTR colonized by Methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant enterococci (VRE), extended-spectrum ß-lactamase (ESBL) or carbapenem-resistant Enterobacteriaceae. (CRE), or MDR-pseudomonas, and compared to noncolonized, were included. Two reviewers assessed eligibility, conducted a risk of bias evaluation using the Newcastle-Ottawa Scale, and rated certainty of evidence using the GRADE approach. METHODS OF DATA SYNTHESIS: We employed RevMan for a meta-analysis, using random-effects models to compute pooled odds ratios (OR) and 95% confidence intervals (CI). Statistical heterogeneity was determined using the I2 statistic. RESULTS: 15,202 SOTR (33 cohort, six case-control studies) were included, where liver transplant and VRE colonization (25 and 14 studies) were predominant. MDR colonization significantly increased posttransplant 1-year mortality (OR, 2.35; 95% CI, 1.63-3.38) and mixed infections (OR, 10.74; 95% CI, 7.56-12.26) across transplant types (p < 0.001 and I2 = 58%), but no detected impact on graft loss (p 0.41, I2 = 0). Subgroup analysis indicated a higher association between CRE or ESBL colonization with outcomes (CRE: death OR, 3.94; mixed infections OR, 24.8; ESBL: mixed infections OR, 10.3; no mortality data) compared to MRSA (Death: OR, 2.25; mixed infection: OR, 7.75) or VRE colonization (Death: p 0.20, mixed infections: OR, 5.71). CONCLUSIONS: MDR colonization in SOTR, particularly CRE, is associated with increased mortality. Despite the low certainty of the evidence, actions to prevent MDR colonization in transplant candidates are warranted.

The Relationships of Dentition, Use of Dental Prothesis and Oral Health Problems with Frailty, Disability and Diet Quality: Results from Population-Based Studies of Older Adults from the UK and USA.

OBJECTIVES: This study examined the relationships of dental status, use and types of dental prothesis and oral health problems, individually and combined, with diet quality, frailty and disability in two population-based studies of older adults. DESIGN: Cross-sectional study. SETTING AND PARTICIPANTS: Men form the British Regional Heart Study (BRHS) (aged 85±4 years in 2018; n=1013) and Men and Women from the Health, Aging, and Body Composition (HABC) Study (aged 75±3 years in 1998-99; n=1975). MEASUREMENTS: Physical and dental examinations and questionnaires were collected with data available for dental status, oral problems related to eating, diet quality, Fried frailty phenotype, disability based on mobility limitations, and activities of daily living (ADL). The associations of dental status and oral health problems, individually and combined, with risk of frailty and disability were quantified. The relationship with diet quality was also assessed. RESULTS: In the BRHS, but not HABC Study, impaired natural dentition without the use of dentures was associated with frailty independently. This relationship was only established in the same group in those with oral problems (OR=3.24; 95% CI: 1.30-8.03). In the HABC Study, functional dentition with oral health problems was associated with greater risk of frailty (OR=2.21; 95% CI: 1.18-4.15). In both studies those who wore a full or partial denture in one or more jaw who reported oral problems were more likely to have disability. There was no association with diet quality in these groups. CONCLUSION: Older adults with impaired dentition even who use dentures who experience self-report oral problems related to eating may be at increased risk of frailty and disability. Further research is needed to establish whether improving oral problems could potentially reduce the occurrence of frailty and disability.

Genetic susceptibility to dental caries on pit and fissure and smooth surfaces.

Carious lesions are distributed nonuniformly across tooth surfaces of the complete dentition, suggesting that the effects of risk factors may be surface-specific. Whether genes differentially affect caries risk across tooth surfaces is unknown. We investigated the role of genetics on two classes of tooth surfaces, pit and fissure surfaces (PFS) and smooth surfaces (SMS), in more than 2,600 subjects from 740 families. Participants were examined for surface-level evidence of dental caries, and caries scores for permanent and/or primary teeth were generated separately for PFS and SMS. Heritability estimates (h(2), i.e. the proportion of trait variation due to genes) of PFS and SMS caries scores were obtained using likelihood methods. The genetic correlations between PFS and SMS caries scores were calculated to assess the degree to which traits covary due to common genetic effects. Overall, the heritability of caries scores was similar for PFS (h(2) = 19-53%; p < 0.001) and SMS (h(2) = 17-42%; p < 0.001). Heritability of caries scores for both PFS and SMS in the primary dentition was greater than in the permanent dentition and total dentition. With one exception, the genetic correlation between PFS and SMS caries scores was not significantly different from 100%, indicating that (mostly) common genes are involved in the risk of caries for both surface types. Genetic correlation for the primary dentition dfs (decay + filled surfaces) was significantly less than 100% (p < 0.001), indicating that genetic factors may exert differential effects on caries risk in PFS versus SMS in the primary dentition.

Plaque Microbiome in Caries-Active and Caries-Free Teeth by Dentition.

OBJECTIVE: Describe associations between dental caries and dental plaque microbiome, by dentition and family membership. METHODS: This cross-sectional analysis included 584 participants in the Center for Oral Health Research in Appalachia Cohort 1 (COHRA1). We sequenced the 16S ribosomal RNA gene (V4 region) of frozen supragingival plaque, collected 10 y prior, from 185 caries-active (enamel and dentinal) and 565 caries-free (no lesions) teeth using the Illumina MiSeq platform. Sequences were filtered using the R DADA2 package and assigned taxonomy using the Human Oral Microbiome Database. RESULTS: Microbiomes of caries-active and caries-free teeth were most similar in primary dentition and least similar in permanent dentition, but caries-active teeth were significantly less diverse than caries-free teeth in all dentition types. Streptococcus mutans had greater relative abundance in caries-active than caries-free teeth in all dentition types (P < 0.01), as did Veillonella dispar in primary and mixed dentition (P < 0.01). Fusobacterium sp. HMT 203 had significantly higher relative abundance in caries-free than caries-active teeth in all dentition types (P < 0.01). In a linear mixed model adjusted for confounders, the relative abundance of S. mutans was significantly greater in plaque from caries-active than caries-free teeth (P < 0.001), and the relative abundance of Fusobacterium sp. HMT 203 was significantly lower in plaque from caries-active than caries-free teeth (P < 0.001). Adding an effect for family improved model fit for Fusobacterium sp. HMT 203 but notS. mutans. CONCLUSIONS: The diversity of supragingival plaque composition from caries-active and caries-free teeth changed with dentition, but S. mutans was positively and Fusobacterium sp. HMT 203 was negatively associated with caries regardless of dentition. There was a strong effect of family on the associations of Fusobacterium sp. HMT 203 with the caries-free state, but this was not true for S. mutans and the caries-active state. KNOWLEDGE TRANSFER STATEMENT: Patients' and dentists' concerns about transmission of bacteria within families causing caries should be tempered by the evidence that some shared bacteria may contribute to good oral health.

Genome-wide Scan of Dental Fear and Anxiety Nominates Novel Genes.

Dental care-related fear and anxiety (DFA) is prevalent, affects oral health care utilization, and is related to poor oral health and decreased quality of life. In addition to learned and cultural factors, genetics is hypothesized to contribute to DFA. Therefore, we performed a genome-wide association study to identify genetic variants contributing to DFA. Adult and adolescent participants were from 4 cohorts (3 from the US-based Center for Oral Health Research in Appalachia, n = 1,144, 1,164, and 535, and the UK-based Avon Longitudinal Study of Parents and Children [ALSPAC], n = 2,078). Two self-report instruments were used to assess DFA: the Dental Fear Survey (US cohorts) and Corah's Dental Anxiety Scale (ALSPAC). Genome-wide scans were performed for the DFA total scores and subscale scores (avoidance, physiological arousal, fear of dental treatment-specific stimuli), adjusting for age, sex, educational attainment, recruitment site, and genetic ancestry. Results across cohorts were combined using meta-analysis. Heritability estimates for DFA total and subscale scores were similar across cohorts and ranged from 23% to 59%. The meta-analysis revealed 3 significant (P < 5E-8) associations between genetic loci and 2 DFA subscales: physiological arousal and avoidance. Nearby genes included NTSR1 (P = 3.05E-8), DMRTA1 (P = 4.40E-8), and FAM84A (P = 7.72E-9). Of these, NTSR1, which was associated with the avoidance subscale, mediates neurotensin function, and its deficiency may lead to altered fear memory in mice. Gene enrichment analyses indicated that loci associated with the DFA total score and physiological arousal subscale score were enriched for genes associated with severe and persistent mental health (e.g., schizophrenia) and neurocognitive (e.g., autism) disorders. Heritability analysis indicated that DFA is partly explained by genetic factors, and our association results suggested shared genetic underpinnings with other psychological conditions.

Global oral health inequalities: task group--implementation and delivery of oral health strategies.

This paper reviews the shortcomings of present approaches to reduce oral diseases and inequalities, details the importance of social determinants, and links that to research needs and policies on implementation of strategies to reduce oral health inequalities. Inequalities in health are not narrowing. Attention is therefore being directed at determinants of major health conditions and the extent to which those common determinants vary within, between, and among groups, because if inequalities in health vary across groups, then so must underlying causes. Tackling inequalities in health requires strategies tailored to determinants and needs of each group along the social gradient. Approaches focusing mainly on downstream lifestyle and behavioral factors have limited success in reducing health inequalities. They fail to address social determinants, for changing people's behaviors requires changing their environment. There is a dearth of oral health research on social determinants that cause health-compromising behaviors and on risk factors common to some chronic diseases. The gap between what is known and implemented by other health disciplines and the dental fraternity needs addressing. To re-orient oral health research, practice, and policy toward a 'social determinants' model, a closer collaboration between and integration of dental and general health research is needed. Here, we suggest a research agenda that should lead to reductions in global inequalities in oral health.

Pneumocystis jirovecii: a review with a focus on prevention and treatment.

Introduction: Pneumocystis jirovecii (PJ) is an opportunistic fungal pathogen that can cause severe pneumonia in immunocompromised hosts. Risk factors for Pneumocystis jirovecii pneumonia (PJP) include HIV, organ transplant, malignancy, certain inflammatory or rheumatologic conditions, and associated therapies and conditions that result in cell-mediated immune deficiency. Clinical signs of PJP are nonspecific and definitive diagnosis requires direct detection of the organism in lower respiratory secretions or tissue. First-line therapy for prophylaxis and treatment remains trimethoprim-sulfamethoxazole (TMP-SMX), though intolerance or allergy, and rarely treatment failure, may necessitate alternate therapeutics, such as dapsone, pentamidine, atovaquone, clindamycin, primaquine and most recently, echinocandins as adjunctive therapy. In people living with HIV (PLWH), adjunctive corticosteroid use in treatment has shown a mortality benefit.Areas covered: This review article covers the epidemiology, pathophysiology, diagnosis, microbiology, prophylaxis indications, prophylactic therapies, and treatments.Expert opinion: TMP-SMX has been first-line therapy for treating and preventing pneumocystis for decades. However, its adverse effects are not uncommon, particularly during treatment. Second-line therapies may be better tolerated, but often sacrifice efficacy. Echinocandins show some promise for new combination therapies; however, further studies are needed to define optimal antimicrobial therapy for PJP as well as the role of corticosteroids in those without HIV.

Opposition to Early Dental Visit by Dentists: A Qualitative Study on Mothers' Social Networks.

OBJECTIVES: To examine whether information that mothers received from dentists in their social network was consistent with professional recommendations for the first dental visit at age 1 y. METHODS: We performed a cross-sectional qualitative study on mothers in Pennsylvania and West Virginia from 2018 to 2020 to explore how their social networks influence their children's dental service utilization. In-person, semistructured interviews were conducted with 126 mothers of children ages 3 to 5 y. Qualitative data were transcribed, coded, and analyzed using NVivo 12. Two investigators analyzed data using grounded theory and the constant comparative method. RESULTS: Over half of mothers reported a professional relationship with a dentist as part of their social network on children's oral health. Mothers described the following themes: 1) mothers contacted dentists in their social network for child dental information and to schedule their child's first dental visit, 2) mothers described dentists' justifications for the timing of the first dental visit older than age 1 y, 3) mothers described the impact of the dentist declining to see her child, and 4) after the dentist declined to see her child, some mothers did not comply with the dentist's recommendation of delayed child dental visits because they were given alternative information that encouraged early dental visits. CONCLUSIONS: Our findings indicate a need for dentists to reinforce mothers' dental-seeking behavior for young children and adhere to recommendations on the age 1 dental visit. KNOWLEDGE TRANSFER STATEMENT: Qualitative data on mothers' social networks show that dentists play a key role in access to early dental visits, particularly when dentists decline to see the mother's child for visits.

Genes and their effects on dental caries may differ between primary and permanent dentitions.

The importance of genetic factors in the genesis of dental caries of both primary and permanent dentitions is well established; however, the degree to which genes contribute to the development of dental caries, and whether these genes differ between primary and permanent dentitions, is largely unknown. Using family-based likelihood methods, we assessed the heritability of caries-related phenotypes for both children and adults in 2,600 participants from 740 families. We found that caries phenotypes in the primary dentition were highly heritable, with genes accounting for 54-70% of variation in caries scores. The heritability of caries scores in the permanent dentition was also substantial (35-55%, all p < 0.01), although this was lower than analogous phenotypes in the primary dentition. Assessment of the genetic correlation between primary and permanent caries scores indicated that 18% of the covariation in these traits was due to common genetic factors (p < 0.01). Therefore, dental caries in primary and permanent teeth may be partly attributable to different suites of genes or genes with differential effects. Sex and age explained much of the phenotypic variation in permanent, but not primary, dentition. Further, including pre-cavitated white-spot lesions in the phenotype definition substantially increased the heritability estimates for dental caries. In conclusion, our results show that dental caries are heritable, and suggest that genes affecting susceptibility to caries in the primary dentition may differ from those in permanent teeth. Moreover, metrics for quantifying caries that incorporate white-spot lesions may serve as better phenotypes in genetic studies of the causes of tooth decay.

Nonrestorative Treatments for Caries: Systematic Review and Network Meta-analysis.

The goal of nonrestorative or non- and microinvasive caries treatment (fluoride- and nonfluoride-based interventions) is to manage the caries disease process at a lesion level and minimize the loss of sound tooth structure. The purpose of this systematic review and network meta-analysis was to summarize the available evidence on nonrestorative treatments for the outcomes of 1) arrest or reversal of noncavitated and cavitated carious lesions on primary and permanent teeth and 2) adverse events. We included parallel and split-mouth randomized controlled trials where patients were followed for any length of time. Studies were identified with MEDLINE and Embase via Ovid, Cochrane CENTRAL, and Cochrane Database of Systematic Reviews. Pairs of reviewers independently conducted the selection of studies, data extraction, risk-of-bias assessments, and assessment of the certainty in the evidence with the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach. Data were synthesized with a random effects model and a frequentist approach. Forty-four trials (48 reports) were eligible, which included 7,378 participants and assessed the effect of 22 interventions in arresting or reversing noncavitated or cavitated carious lesions. Four network meta-analyses suggested that sealants + 5% sodium fluoride (NaF) varnish, resin infiltration + 5% NaF varnish, and 5,000-ppm F (1.1% NaF) toothpaste or gel were the most effective for arresting or reversing noncavitated occlusal, approximal, and noncavitated and cavitated root carious lesions on primary and/or permanent teeth, respectively (low- to moderate-certainty evidence). Study-level data indicated that 5% NaF varnish was the most effective for arresting or reversing noncavitated facial/lingual carious lesions (low certainty) and that 38% silver diamine fluoride solution applied biannually was the most effective for arresting advanced cavitated carious lesions on any coronal surface (moderate to high certainty). Preventing the onset of caries is the ultimate goal of a caries management plan. However, if the disease is present, there is a variety of effective interventions to treat carious lesions nonrestoratively.

Microbial acid production (Clinpro Cario L-Pop) and dental caries in infants and children.

OBJECTIVE: The purpose of this study was to evaluate the diagnostic utility of the Clinpro Cario-L-Pop test as it relates to dental caries rates and severity in infants and children. METHOD AND MATERIALS: The study population was comprised of 771 infants and children who were on average 5.2 years of age (range of 1.5 to 8 years of age). Examiners conducted dental caries clinical examination using established criteria. In addition, lesion severity was determined be measuring its depth. An indicator swab was applied to the tongue dorsum until completely moistened with saliva. The indicator swab was processed according to the manufacturer's instructions, and acid production was assessed with the aid of a color chart. RESULTS: Twenty-three percent of children were caries free, and 7% (n = 50) of participants were categorized as having low production of lactic acid (scores 1 to 3), 17% (n = 135) moderate production of lactic acid (scores 4 to 6), and 76% (n = 586) high production of lactic acid (scores 7 to 9). There was a tendency for moderate and high lactic acid formers to exhibit higher surface-based caries prevalence rates, higher rates for deep dentinal lesions, and increased lesion severity. There was a linear increase of white spot surface-based lesions from low to high lactic acid formers and for initial dentinal lesions. Clinpro Cario-L-Pop test results, when controlling for age and gender, significantly distinguished caries-free participants from those exhibiting any form of decay. CONCLUSION: These results suggest that Clinpro Cario-L-Pop test was useful in explaining elevated frequency and severity of dental caries in spite of the high levels of decay and of microbial acid production observed in this population.

Bayesian Analysis of the Association between Family-Level Factors and Siblings' Dental Caries.

We conducted a Bayesian analysis of the association between family-level socioeconomic status and smoking and the prevalence of dental caries among siblings (children from infant to 14 y) among children living in rural and urban Northern Appalachia using data from the Center for Oral Health Research in Appalachia (COHRA). The observed proportion of siblings sharing caries was significantly different from predicted assuming siblings' caries status was independent. Using a Bayesian hierarchical model, we found the inclusion of a household factor significantly improved the goodness of fit. Other findings showed an inverse association between parental education and siblings' caries and a positive association between households with smokers and siblings' caries. Our study strengthens existing evidence suggesting that increased parental education and decreased parental cigarette smoking are associated with reduced childhood caries in the household. Our results also demonstrate the value of a Bayesian approach, which allows us to include household as a random effect, thereby providing more accurate estimates than obtained using generalized linear mixed models.

Genetic Association of MMP10, MMP14, and MMP16 with Dental Caries.

Matrix metalloproteinases (MMPs), which degrade extracellular proteins as part of a variety of physiological processes, and their inhibitors have been implicated in the dental caries process. Here we investigated 28 genetic variants spanning the MMP10, MMP14, and MMP16 genes to detect association with dental caries experience in 13 age- and race-stratified (n = 3,587) samples from 6 parent studies. Analyses were performed separately for each sample, and results were combined across samples by meta-analysis. Two SNPs (rs2046315 and rs10429371) upstream of MMP16 were significantly associated with caries in an individual sample of white adults and via meta-analysis across 8 adult samples after gene-wise adjustment for multiple comparisons. Noteworthy is SNP rs2046315 (p = 8.14 × 10-8) association with caries in white adults. This SNP was originally nominated in a genome-wide-association study (GWAS) of dental caries in a sample of white adults and yielded associations in a subsequent GWAS of surface level caries in white adults as well. Therefore, in our study, we were able to recapture the association between rs2046315 and dental caries in white adults. Although we did not strengthen evidence that MMPs 10, 14, and 16 influence caries risk, MMP16 is still a likely candidate gene to pursue.

Association of immunoreactive hepatocyte growth factor with poor survival in resectable non-small cell lung cancer.

We have shown previously that hepatocyte growth factor (HGF), which is produced by lung fibroblasts, is a potent mitogen and motogen for both normal and neoplastic bronchial epithelium, and that expression of the HGF receptor, the c-met proto-oncogene protein, is uniformly found in the human bronchial epithelium and in non-small cell lung carcinomas (NSCLCs; P. Singh-Kaw et al., Am. J. Physiol., 268: L1012-L1020, 1995). Yamashita et al. have reported an association of HGF with poor survival in invasive ductal carcinoma of the breast (Cancer Res., 54: 1630-1633, 1994). There are few prognostic markers for lung cancer, and the high recurrence rate for stage I lung cancer suggests the frequent presence of undetectable tumor burden in such patients. Criteria are needed to evaluate these patients for risk of recurrence. We have now evaluated whether HGF present in resectable lung tumors has prognostic significance. In this study, 56 primary NSCLCs, mainly adenocarcinomas, were examined for presence of HGF by quantitative Western blot. These tumors consisted of tissue from 34 stage I patients, 9 stage II patients, and 13 stage IIIa patients who underwent curative resection for primary NSCLC. Extracts of whole tumor tissue were analyzed after separation of proteins by electrophoresis and transfer of proteins to nitrocellulose membranes. Immunoreactive (ir)-HGF was visualized by reaction with a polyclonal anti-HGF antiserum and quantitated by densitometry. Lung tumor content of ir-HGF varied widely among individuals. Median ir-HGF content in tumor extracts was 15.3 ng/40 microg of tumor protein; mean ir-HGF was 27.2 ng/40 microg of tumor protein. The median and mean ir-HGF were both significantly higher in tumor tissue from patients who suffered a recurrence during the follow-up period compared with those with no evidence or residual disease; this was true of all patients (P = 0.0001) and stage I patients analyzed separately (P = 0.002). Analysis of survival curves indicated that ir-HGF levels higher than the median were associated with poor overall survival (P < 0.03). Univariate analysis showed three factors related to poor overall survival in this set of patients: ir-HGF, tumor (T) status (a measure of primary tumor size and extent), and age. Nodal (N) status and stage were only marginally related to overall survival, most likely because the majority of the patients in the study were stage I. N status, stage, and T status were related to disease-free survival, however. Multivariate Cox analysis showed that ir-HGF, T status, and age independently had a negative impact on overall survival. ir-HGF was a strong independent negative prognostic indicator (P = 0.0001) with a relative risk of 1.022 per unit of ir-HGF (ng/40 microg of protein). This demonstrates that, in this group of patients, the relative risk of ir-HGF content increased continuously as ir-HGF increased, and exceeded 10 at units of ir-HGF of 100 or more. In comparison, in this group of patients, the relative risk of a T status greater than 1 was 4.75 and that of age greater than 65 was 3.95. The combined negative effect of a T status greater than 1 and elevated ir-HGF on survival was also highly pronounced (P < 0.005). In addition, elevated ir-HGF had a negative impact on survival when patients were stratified by stage or N status. Stage I patients with high ir-HGF values had a worse outcome than stage II or stage IIIa patients with low ir-HGF values. Elevated ir-HGF was strongly associated with poor outcome for resectable NSCLC patients as a group, and also identified stage I patients with poor outcome, indicating that it could be a useful indicator of risk of relapse and death in patients who have early lung cancer. The impact of elevated ir-HGF was especially prominent in patients whose T status was greater than 1, suggesting that patients with both risk factors who are stag

A new definition for oral health developed by the FDI World Dental Federation opens the door to a universal definition of oral health.

This article first published as an editorial in the Journal of the American Dental Association presents the FDI World Dental Federation's universal definition of oral health. This new definition was approved in September 2016 and developed as as part of the FDI's advocacy and strategic plan - Vision 2020.

Fear of Pain Mediates the Association between MC1R Genotype and Dental Fear.

Fear of pain is experienced in acute and chronic pain populations, as well as in the general population, and it affects numerous aspects of the orofacial pain experience, including pain intensity, pain-related disability, and pain behavior (e.g., avoidance). A related but separate construct-dental fear-is also experienced in the general population, and it influences dental treatment-seeking behavior and oral and systemic health. Minimal work has addressed the role of genetics in the etiologies of fear of pain and dental fear. Limited available data suggest that variants of the melanocortin 1 receptor (MC1R) gene may predict greater levels of dental fear. The MC1R gene also may be etiologically important for fear of pain. This study aimed to replicate the finding that MC1R variant status predicts dental fear and to determine, for the first time, whether MC1R variant status predicts fear of pain. Participants were 817 Caucasian participants (62.5% female; mean ± SD age: 34.7 ± 8.7 y) taking part in a cross-sectional project that identified determinants of oral diseases at the community, family, and individual levels. Participants were genotyped for single-nucleotide polymorphisms on MC1R and completed self-report measures of fear of pain and dental fear. Presence of MC1R variant alleles predicted higher levels of dental fear and fear of pain. Importantly, fear of pain mediated the relation between MC1R variant status and dental fear (B = 1.60, 95% confidence interval: 0.281 to 3.056). MC1R variants may influence orofacial pain perception and, in turn, predispose individuals to develop fears about pain. Such fears influence the pain experience and associated pain behaviors, as well as fears about dental treatment. This study provides support for genetic contributions to the development/maintenance of fear of pain and dental fear, and it offers directions for future research to identify potential targets for intervention in the treatment of fear of pain and dental fear.

Longitudinal analysis of heritability for dental caries traits.

The role of genetic and environmental factors on dental caries progression in young children was determined. A detailed caries assessment was performed in 2 examinations on 314 pairs of twins initially 1.5 to 8 years old. Surface-based caries prevalence rates (SBCPR) and lesion severity (LSI) were computed. Heritability estimates were calculated by SOLAR software. Analyses were performed on all ages combined and by age group (1.5-< 4; 4-6; > 6). Overall heritability estimates (H) of net increments SBCPRs were H = 30.0 (p < 0.0001), and were greatest for the youngest (H = 30.0) and oldest groups (H = 46.3). Overall LSI heritability estimates [H = 36.1 (p < 0.0001)] were also greatest for the youngest (H = 51.2) and oldest groups (H = 50.6). Similar findings were found for net increments of occlusal surfaces and deep dentinal lesions SBCPRs (H = 46.4-56.2). These findings are consistent with a significant genetic contribution to dental caries progression and severity in both emerging primary and permanent dentitions.

Detection of K-ras mutations in lung carcinomas: relationship to prognosis.

The K-ras mutation is one of the most common genetic alterations found in human lung cancer. To evaluate the prognostic value of ras gene alterations in lung cancer in a U.S. population, we have screened 173 human lung tumors, which included 127 adenocarcinomas, 37 squamous carcinomas, and 9 adenosquamous carcinomas, for mutations in the K-ras gene using the combination of the PCR and denaturing gradient gel electrophoresis. Forty-three tumors contained K-ras mutations. Of these, 41 were identified among the adenocarcinomas (32%), 1 among the squamous carcinomas (2.7%), and 1 among the adenosquamous carcinomas (11%). Forty of these mutations were found in codon 12 and consisted of 24 G to T transversions, 12 G to A transitions, 2 G to C transversions, and 1 double GG to TT mutation. Two other G to T transversions were found in codon 13, and 1 A to C transversion was found in codon 61. The data showed that gender did not seem to affect the incidence and the types of the K-ras mutations or amino acid changes. Examination of the mutations in adenocarcinomas in relation to overall survival showed no difference in adenocarcinomas with K-ras mutations compared with K-ras-negative adenocarcinomas. However, the substitution of the wild-type GGT (glycine) at codon 12 with a GTT (valine) or a CGT (arginine) showed a strong trend (P = 0.07) toward a poorer prognosis compared with wild-type or other amino acid substitutions. Substitution of the wild-type glycine for aspartate (GAT) showed a strong trend (P = 0.06) for a better outcome than the valine or arginine substitution. Although these trends will require larger patient populations for verification, these data suggest that the prognostic significance of K-ras mutations may depend on the amino acid substitution in the p21(ras) protein.