bluuebunny/crossref_metadata_2025_split huggingface dataset:
Anxiety sensitivity as predictor of pain in patients undergoing restorative dental procedures
Authors: Klages Ulrich , Kianifard Simin , Ulusoy Özlem , Wehrbein Heinrich 
Published: March 2006

Abstract –  Objectives:  The personality disposition to anxiety sensitivity refers to beliefs about negative consequences of bodily arousal. The concept has recently been successfully applied in research on chronic pain conditions. The present study investigated whether anxiety sensitivity interacts with dental fear to increase expected and experienced pain during routine dental treatment.Methods:  Subjects were 97 patients undergoing dental procedures of excavation and filling. Anxiety dispositions were measured by the Anxiety Sensitivity Index and the Dental Anxiety Scale. Expected and experienced pain were assessed by affective and sensory verbal descriptor scales and a numerical rating scale measuring pain intensity.Results:  Dentally fearful patients scoring high in anxiety sensitivity both expected and experienced more pain than low scorers did. Significant interactions were found predicting expected affective and intense pain and experienced pain intensity.Conclusion:  The results lend support to the assumption that dentally fearful patients with a disposition to high anxiety sensitivity amplify pain anticipations when exposed to the critical situation. When dentally fearful patients are under treatment, their beliefs about negative consequences of bodily arousal may negatively influence their evaluation of treatment related pain.
Application of nonhomogenous Markov models for analyzing longitudinal caries risk
Authors: Kopycka‐Kędzierawski D. T. , Billings R. J. 
Published: March 2006

Abstract –  Objectives:  Markov modeling is a useful mathematical procedure for calculating probabilities of disease prognosis. Increasingly, Markov models are being applied in medical and health services research and also in social sciences research. The purpose of our study was to use the Markov process to determine time‐dependent transition probabilities for caries‐free children to convert to a caries‐active state and to assess the impact of salivary mutans streptococci (MS) levels on caries status.Methods:  Our analysis was based on data obtained from a 6‐year longitudinal study of risk factors associated with caries onset in children.Results:  Based on a two‐state Markov model, the probability that a caries‐free child would convert to a caries‐active state during the study ranged between 0.0046 and 0.0471. The highest probability of converting from a caries‐free state to a caries‐active state was 0.0471 at age 8.5 years.Conclusions:  In addition to standard statistical methods of analyzing longitudinal caries data, Markov models show promise for use in the analysis of caries risk.
Multilevel assessment of determinants of dental caries experience in Brazil
Authors: Antunes José Leopoldo Ferreira , Peres Marco Aurélio , Mello Tatiana Ribeiro de Campos , Waldman Eliseu Alves 
Published: March 2006

Abstract –  Objective:  To examine contextual and individual determinants of dental caries experience, documenting levels of the disease in Brazil. Methods:  The dental status of 34 550 12‐year‐old schoolchildren was informed by a country‐wide survey of oral health comprising 250 towns and performed in 2002–2003. Indices assessing dental caries experience were compared by sociodemographic characteristics of examined children (gender, ethnic group, localization and type of school), and geographic characteristics of participating towns [the human development index (HDI), and access to fluoridated tap water]. A multilevel model fitted the adjustment of untreated caries to individual and contextual covariates.Results:  Better‐off Brazilian regions presented an improved profile of dental health, besides having a less unequal distribution of restorative dental treatments between blacks and whites, rural and urban areas, and public and private schools. Girls [odds ratio (OR) = 1.1; 95% confidence interval (CI): 1.0–1.1], blacks (OR = 1.6; 95% CI: 1.5–1.7), and children studying in rural areas (OR = 1.9; 95% CI: 1.7–2.0) and public schools (OR = 1.7; 95% CI: 1.6–1.9) presented higher odds of having untreated decayed teeth. The multilevel model identified the fluoride status of tap water (β = −0.3), the proportion of households linked to the water network (β = −0.3), and the HDI (β = −0.2), as town‐level variables associated with caries levels.Conclusion:  Dental caries experience is prone to sociodemographic and geographic inequalities. The monitoring of contrasts in dental health outcomes is relevant for programming socially appropriate interventions aimed both at overall improvements and at the targeting of resources for groups of population presenting higher levels of needs.
Fibroblast growth factor‐2 expression during experimental oral carcinogenesis. Its possible role in the induction of pre‐malignant fibrosis
Authors: Raimondi A. R. , Molinolo A. A. , Itoiz M. E. 
Published: March 2006

Background:  The fibroblastic growth factor (FGF)‐2 has been shown to induce angiogenesis in several tumor types. To date, the activity of FGF during the development of oral pre‐cancerous lesions has not been analyzed. We herein evaluated the role of FGF‐2 in the pre‐cancerous and cancerous lesions in the hamster cheek pouch oral cancer model.Methods:  Expression of FGF‐2 and its receptors FGFR‐2 and FGFR‐3 was assessed by immunohistochemistry at different stages of the carcinogenesis protocol. Activity of FGF‐2 isoforms was analyzed by Western blots.Results:  Increase and abnormal localization of FGF‐2 expression was evident in cancerized epithelium before it was possible to detect morphologic alterations. The changes in FGF‐2 are concomitant with the evolution of subepithelial fibrosis. Immunolabeling of carcinomas was faint or completely negative. Increases of FGF‐2 activity are mainly due to the increase in the 18 kDa isoform. Receptors 2 and 3 of FGF are present in epithelium, fibroblasts, and vascular endothelia of control samples and in all stages of malignant transformation.Conclusions:  Our results would suggest a role for FGF‐2 in the epithelium–connective interactions and a deregulation of its expression in the early stages of oral cancerization. In pre‐cancerous tissue FGF‐2 would play a central role in the development of fibrosis and a more collateral role in the induction of angiogenesis. The data would indicate its involvement in the process via the 18 kDa isoform.
Salivary interleukin‐6 and tumor necrosis factor‐α in patients with recurrent aphthous ulceration
Authors: Boras V. Vučićević , Lukač J. , Brailo V. , Picek P. , Kordić D. , Žilić I. Alajbeg 
Published: March 2006

Background:  Recurrent apthous ulceration (RAU) is a well known oral disease which seems to be mediated principally by the immune system. However, it is still a matter of debate which part of the immune system is implicated in its pathogenesis as a reaction to the still unknown antigen. The aim of this study was to evaluate salivary cytokines, interleukin (IL)‐6, and tumor necrosis factor (TNF)‐α.Methods:  In 26 patients with minor RAU, age range of 23–49 years (mean 27.3 years), during both the acute phase and remission and in 26 healthy controls, age range of 22–64 years (mean 30.1 years), salivary IL‐6 and TNF‐α levels were determined by use of enzyme‐linked immunosorbent assay (ELISA). Statistical analysis was performed by use of descriptive statistics.Results:  Significant differences in salivary TNF‐α between healthy controls and patients with acute RAU and during the remission period were found (P < 0.001) as well as between patients with acute RAU and those during the remission period (P < 0.001). No differences in salivary IL‐6 between all three groups could be found.Conclusions:  We might conclude that elevated salivary TNF‐α levels during acute RAU and especially during the remission period are of importance in RAU, whereas salivary IL‐6 levels seem not to play a role in the RAU disease.
GSTM1 polymorphism and oral leukoplakia
Authors: Duarte Eliza Carla Barroso , da Silva Marina Sena Lopes , Gomez Marcus Vinícius , Gomez Ricardo Santiago 
Published: March 2006

Background:  Molecular epidemiological studies have now provided evidence that an individual susceptibility to cancer is mediated by genetic and environmental factors. Genetic polymorphisms have been described for enzymes involved in the metabolism of tobacco carcinogens and cancer risk is determined by the degree of expression and/or activity of enzymes involved in carcinogen activation or deactivation. The objective of this study was to investigate the GSTM1 null polymorphism and the risk for oral leukoplakia in individuals with tobacco‐smoking habit in a Brazilian population.Methods:  A total of 52 tobacco‐smoking patients with oral leukoplakia and 52 tobacco‐smoking controls were recruited in a Brazilian population. The GSTM1 genotypes were studied by polymerase chain reaction‐based methods.Results:  The frequency of the GSTM1 null genotype in the group with oral leukoplakia (57.7%) was statistically different from the controls (34.6%; OR: 2.57, 95% CI: 1.16–5.69, P < 0.05). The stratification of the samples according to the level of dysplasia showed increased prevalence of GSTM1 null genotype on lesions with moderate/severe histological dysplasia (68.2%) compared with the control group (31.9%). This difference was statistically significant (OR: 4.59, 95% CI: 1.29–16.33, P < 0.05).Conclusion:  In conclusion, the GSTM1 null genotype may increase the risk for oral leukoplakia development.
The role of histopathological characteristics in distinguishing amalgam‐associated oral lichenoid reactions and oral lichen planus
Authors: Thornhill Martin H. , Sankar Vidya , Xu Xiao‐Jun , Barrett A. William , High Alec S. , Odell Edward W. , Speight Paul M. , Farthing Paula M. 
Published: March 2006

Objectives:  To identify histological features that distinguish amalgam‐associated oral lichenoid reactions (AAOLR) from oral lichen planus (OLP).Methods:  Oral pathologists provided their opinion as to the possibility of distinguishing AAOLR and OLP histologically, the features important in distinguishing AAOLR from OLP and the diagnosis of 12 AAOLR and 12 OLP cases including the features that drew them to their conclusion.Results:  There was considerable variation between pathologists in their ability to distinguish the AAOLR and OLP cases. The sensitivity and specificity for histological diagnosis were 40% and 32% respectively. There were four features that were used most commonly to discriminate between AAOLR and OLP: an inflammatory infiltrate located deep to superficial infiltrate in some or all areas; a focal perivascular infiltrate; plasma cells in the connective tissue and neutrophils in the connective tissue. Each was independently predictive of AAOLR or OLP (P < 0.028).Conclusions:  This study confirms the uncertainty of the diagnostic histological differences between AAOLR and OLP. Distinguishing these conditions should not rely on histology alone, but should be based on a synthesis of all available information including history, examination, histopathology and skin patch testing.
Gene expression analysis by cDNA microarray in oral squamous cell carcinoma
Authors: Tomioka Hirofumi , Morita Kei‐ichi , Hasegawa Shogo , Omura Ken 
Published: March 2006

Background:  Oral squamous cell carcinoma (OSCC) is common type of human cancer, but little is known about the molecular mechanisms deciding on this malignancy. Comprehensive gene expression profiling is essential for understanding OSCC.Methods:  cDNA microarray was used to analyze expression patterns of 16 617 genes in nine OSCC patients.Results:  Forty‐seven genes with altered expression among all cases were extracted. The ontology of these 47 genes was classified into 10 categories. To validate the microarray data, the expression of genes, including TGFBI, FADD and DUSP1 was analyzed by reverse transcriptase‐polymerase chain reaction (RT‐PCR). By hierarchical clustering analysis, the nine cases were divided into two clusters.Conclusions:  The 47 genes are suggested as having a functional significance in oral squamous cell carcinogenesis. It is also suggested that the gene expression patterns by hierarchical clustering analysis can represent degrees of differentiation. The postoperative recovery was uneventful and patients free from tumor after surgery. In the future, on the occasion when the time comes that the number of cases accumulated for microarray increases and each case is observed more over a long‐term, these data of 5‐year survival rate will be added. Thereby, it will become possible to represent the malignancy of OSCC by these gene expression patterns.
A simple test for salivary gland hypofunction using Oral Schirmer's test
Authors: López‐Jornet Pia , Camacho‐Alonso Fabio , Bermejo‐Fenoll Ambrosio 
Published: March 2006

Objective: The objective of this study was to develop a test for detecting salivary gland hypofunction.Study Design: Oral Schirmer's test was performed by placing a strip of filter paper on the floor of the mouth and measuring the wetted length after 5 min. The control group consisted of 70 healthy patients, while another group consisted of 61 patients with Sjögren's Syndrome (SS) and a third group of 31 patients who suffered from xerostomia caused by other pathologies.Results: The mean saliva flow was 40.92 ± 22.28 mm/5 min in the control group, 27.25 ± 24.11 mm/5 min in patients with SS and 36.847 ± 23.4 mm/5 min in the third group. The differences between the control group and the other two groups were statistically different (P > 0.001).Conclusions: The whole saliva test was used to distinguish between healthy adults and subjects with hyposalivation.
The decline and fall of GRS 1915+105: the end is nigh?
Authors: Truss Michael , Done Chris 
Published: March 2006

Abstract
The Galactic microquasar GRS 1915+105 has been in a continuous state of outburst since 1992, over 20 times longer than any other black hole X-ray transient. Assuming that the outburst is powered via accretion of an irradiated gaseous disc, we calculate how the predicted outburst duration varies according to the efficiency of the self-irradiation mechanism. At least one current model leads to the conclusion that the end of the outburst is imminent. The timing of the decline of GRS 1915+105, whenever it arrives, will be an excellent discriminator of the self-irradiation mechanism in X-ray transients, allowing us to infer the fraction of the disc that is heated by the incident X-rays and the magnitude of the mass loss rate in the form of a wind.
Fast and Frugal Heuristics1
Authors: Bishop Michael A. 
Published: March 2006

AbstractA heuristic is a rule of thumb. In psychology, heuristics are relatively simple rules for making judgments. A fast heuristic is easy to use and allows one to make judgments quickly. A frugal heuristic relies on a small fraction of the available evidence in making judgments. Typically, fast and frugal heuristics (FFHs) have, or are claimed to have, a further property: They are very reliable, yielding judgments that are about as accurate in the long run as ideal non‐fast, non‐frugal rules. This paper introduces some well‐known examples of FFHs, raises some objections to the FFH program, and looks at the implications of those parts of the FFH program about which we can have some reasonable degree of confidence.
Sedolisins, a New Class of Secreted Proteases fromAspergillus fumigatuswith Endoprotease or Tripeptidyl-Peptidase Activity at Acidic pHs
Authors: Reichard Utz , Léchenne Barbara , Asif Abdul R. , Streit Frank , Grouzmann Eric , Jousson Olivier , Monod Michel 
Published: March 2006

ABSTRACTThe secreted proteolytic activity ofAspergillus fumigatusis of potential importance as a virulence factor and in the industrial hydrolysis of protein sources. TheA. fumigatusgenome contains sequences that could encode a five-member gene family that produces proteases in the sedolisin family (MEROPS S53). Four putative secreted sedolisins with a predicted 17- to 20-amino-acid signal sequence were identified and termed SedA to SedD. SedA produced heterologously inPichia pastoriswas an acidic endoprotease. Heterologously produced SedB, SedC, and SedD were tripeptidyl-peptidases (TPP) with a common specificity for tripeptide-p-nitroanilide substrates at acidic pHs. Purified SedB hydrolyzed the peptide Ala-Pro-Gly-Asp-Arg-Ile-Tyr-Val-His-Pro-Phe to Arg-Pro-Gly, Asp-Arg-Ile, and Tyr-Val-His-Pro-Phe, thereby confirming TPP activity of the enzyme. SedB, SedC, and SedD were detected by Western blotting in culture supernatants ofA. fumigatusgrown in a medium containing hemoglobin as the sole nitrogen source. A degradation product of SedA also was observed. A search for genes encoding sedolisin homologues in other fungal genomes indicates that sedolisin gene families are widespread among filamentous ascomycetes.
Transcriptional Analysis of the Toxin-Coding Plasmid pBtoxis from
Bacillus thuringiensis
subsp.
israelensis
Authors: Stein Claudia , Jones Gareth W. , Chalmers Tanya , Berry Colin 
Published: March 2006

ABSTRACT

In
Bacillus thuringiensis
subsp.
israelensis
all of the insecticidal toxins are encoded on a single, large plasmid, pBtoxis. Sequencing of this plasmid revealed 125 potential coding sequences, many of which have predicted functions in gene regulation and physiological processes, such as germination. As a first step in understanding the possible role of pBtoxis in its host bacterium, a survey of the transcription of genes with predicted functions was carried out. Whereas many coding sequences, including those previously identified as probable pseudogenes, were not transcribed, mRNA was detected for 29 of the 40 sequences surveyed. Several of these sequences, including eight with similarities to the sequences of known transcriptional regulators, may influence wider gene regulation and thus may alter the phenotype of the host bacterium.
Freeze-Thaw Tolerance and Clues to the Winter Survival of a Soil Community
Authors: Walker Virginia K. , Palmer Gerald R. , Voordouw Gerrit 
Published: March 2006

ABSTRACT

Although efforts have been made to sample microorganisms from polar regions and to investigate a few of the properties that facilitate survival at freezing or subzero temperatures, soil communities that overwinter in areas exposed to alternate freezing and thawing caused by Foehn or Chinook winds have been largely overlooked. We designed and constructed a cryocycler to automatically subject soil cultures to alternating freeze-thaw cycles. After 48 freeze-thaw cycles, control
Escherichia coli
and
Pseudomonas chlororaphis
isolates were no longer viable. Mixed cultures derived from soil samples collected from a Chinook zone showed that the population complexity and viability were reduced after 48 cycles. However, when bacteria that were still viable after the freeze-thaw treatments were used to obtain selected cultures, these cultures proved to be >1,000-fold more freeze-thaw tolerant than the original consortium. Single-colony isolates obtained from survivors after an additional 48 freeze-thaw cycles were putatively identified by 16S RNA gene fragment sequencing. Five different genera were recognized, and one of the cultures,
Chryseobacterium
sp. strain C14, inhibited ice recrystallization, a property characteristic of antifreeze proteins that prevents the growth of large, potentially damaging ice crystals at temperatures close to the melting temperature. This strain was also notable since cell-free medium derived from cultures of it appeared to enhance the multiple freeze-thaw survival of another isolate,
Enterococcus
sp. strain C8. The results of this study and the development of a cryocycler should allow further investigations into the biochemical and soil community adaptations to the rigors of a Chinook environment.
Characterization of Two Polyketide Synthase Genes Involved in Zearalenone Biosynthesis in
Gibberella zeae
Authors: Gaffoor Iffa , Trail Frances 
Published: March 2006

ABSTRACT

Zearalenone, a mycotoxin produced by several
Fusarium
spp., is most commonly found as a contaminant in stored grain and has chronic estrogenic effects on mammals. Zearalenone is a polyketide derived from the sequential condensation of multiple acetate units by a polyketide synthase (PKS), but the genetics of its biosynthesis are not understood. We cloned two genes, designated
ZEA1
and
ZEA2
, which encode polyketide synthases that participate in the biosynthesis of zearalenone by
Gibberella zeae
(anamorph
Fusarium graminearum
). Disruption of either gene resulted in the loss of zearalenone production under inducing conditions.
ZEA1
and
ZEA2
are transcribed divergently from a common promoter region. Quantitative PCR analysis of both PKS genes and six flanking genes supports the view that the two polyketide synthases make up the core biosynthetic unit for zearalenone biosynthesis. An appreciation of the genetics of zearalenone biosynthesis is needed to understand how zearalenone is synthesized under field conditions that result in the contamination of grain.
Control of Substrate Specificity by Active-Site Residues in Nitrobenzene Dioxygenase
Authors: Ju Kou-San , Parales Rebecca E. 
Published: March 2006

ABSTRACT

Nitrobenzene 1,2-dioxygenase from
Comamonas
sp. strain JS765 catalyzes the initial reaction in nitrobenzene degradation, forming catechol and nitrite. The enzyme also oxidizes the aromatic rings of mono- and dinitrotoluenes at the nitro-substituted carbon, but the basis for this specificity is not understood. In this study, site-directed mutagenesis was used to modify the active site of nitrobenzene dioxygenase, and the contribution of specific residues in controlling substrate specificity and enzyme performance was evaluated. The activities of six mutant enzymes indicated that the residues at positions 258, 293, and 350 in the α subunit are important for determining regiospecificity with nitroarene substrates and enantiospecificity with naphthalene. The results provide an explanation for the characteristic specificity with nitroarene substrates. Based on the structure of nitrobenzene dioxygenase, substitution of valine for the asparagine at position 258 should eliminate a hydrogen bond between the substrate nitro group and the amino group of asparagine. Up to 99% of the mononitrotoluene oxidation products formed by the N258V mutant were nitrobenzyl alcohols rather than catechols, supporting the importance of this hydrogen bond in positioning substrates in the active site for ring oxidation. Similar results were obtained with an I350F mutant, where the formation of the hydrogen bond appeared to be prevented by steric interference. The specificity of enzymes with substitutions at position 293 varied depending on the residue present. Compared to the wild type, the F293Q mutant was 2.5 times faster at oxidizing 2,6-dinitrotoluene while retaining a similar

K
m

for the substrate based on product formation rates and whole-cell kinetics.