Tooth-wear patterns in adolescents with normal occlusion and Class II Division 2 malocclusion

Introduction: In this study, we investigated tooth-wear patterns in adolescents with either normal occlusion or Class II Division 2 malocclusion. Methods: The sample consisted of dental casts from 165 subjects that were divided into 2 groups: 115 normal occlusion subjects (mean age, 14.3 years) and 50 complete Class II Division 2 subjects (mean age, 13.9 years). Dental wear was assessed by using a modified version of the tooth wear index. The 2 groups were compared with the Mann-Whitney test for the frequency and severity of wear on each surface of each group of teeth. The level of statistical significance was set at 5%. Results: The normal occlusion group statistically had greater tooth wear on the incisal surfaces of the maxillary lateral incisors and the incisal surfaces of the maxillary canines than did the Class II Division 2 malocclusion group. The malocclusion group showed statistically greater tooth wear on the labial surfaces of the mandibular lateral incisors, the occlusal surfaces of the maxillary premolars and first molars, the occlusal surfaces of the mandibular premolars, the palatal surfaces of the maxillary second premolars, and the buccal surfaces of the mandibular premolars and first molars than did the normal occlusion group. Conclusions: Subjects with normal occlusion and those with complete Class II Division 2 malocclusions have different tooth-wear patterns. Tooth wear on the malocclusion subjects should not be considered pathologic but, rather, the consequence of different interocclusal arrangements. (Am J Orthod Dentofacial Orthop 2010;137:730.e1-730.e5)

Tooth-wear patterns in subjects with Class II Division 1 malocclusion and normal occlusion

Introduction: The aim of this study was to investigate the prevalence of tooth wear in adolescents with Class II malocclusion, compared with those with normal occlusion. Methods: The sample consisted of dental casts obtained from 310 subjects, divided into 3 groups: group 1, 110 subjects with normal occlusion (mean age, 13.51 years); group 2, 100 complete Class II Division 1 patients (mean age, 13.44 years); and group 3, 100 half-cusp Class II Division 1 patients (mean age, 13.17 years). Dental wear was assessed by using a modified version of the tooth-wear index. The 3 groups were compared by means of the Kruskal-Wallis and Dunn tests, considering the frequency and the severity of wear on each surface of each group of teeth. The level of statistical significance was set at 5%. Results: The normal occlusion group had statistically greater tooth wear on the palatal surfaces of the maxillary central incisors and the incisal surfaces of the maxillary canines than the corresponding surfaces in both Class II malocclusion groups. The complete and half-cusp Class II Division 1 malocclusion groups had statistically greater tooth wear on the occlusal surfaces of the maxillary second premolar and first molar, the occlusal surfaces of the mandibular premolars, and the buccal surfaces of the mandibular posterior teeth compared with the normal occlusion group. The half-cusp Class II Division 1 malocclusion group had significantly greater tooth wear on the incisal surfaces of the mandibular incisors compared with the complete Class II Division 1 malocclusion group. Conclusions: Subjects with normal occlusion and complete or half-cusp Class II Division 1 malocclusions have different tooth-wear patterns. Tooth wear on the malocclusion subjects should not be considered pathologic but rather consequent to the different interocclusal tooth arrangement. (Am J Orthod Dentofacial Orthop 2010; 137: 14. e1-14.e7)

Evaluation of distances between the mandibular teeth and the alveolar process in Brazilians with normal occlusion

Introduction: The aims of this study were to evaluate the distances between the mandibular permanent teeth and the alveolar process in Brazilians with normal occlusion and to compare them with normal American values. Methods: We used 59 mandibular casts from untreated subjects who had permanent dentition and the 6 keys to normal occlusion. A computer program was used to calculate the distances between the dental reference points and the alveolar process for each tooth. The mean values were then compared to the normal values by applying the Student t test at a significance level of 0.05. Results: The results showed a progressive increase of these distances from the anterior region (incisors) to the posterior region (molars), from 0.00 to 2.49 mm. All measurements had statistically significant differences from the American sample, except for the values for canines and first premolars. Conclusions: Brazilians with normal occlusion have more lingual crown positions for the incisors, second premolars, and molars compared with Americans with normal occlusion. Although these findings were statistically significant, they are unlikely to be clinically significant. (Am J Orthod Dentofacial Orthop 2010; 137: 308.e1-308.e4)

Effect of 2% Chlorhexidine Digluconate on the Bond Strength to Normal Versus Caries-affected Dentin

This study evaluated the effect of 2% chlorhexidine digluconate (CHX) used as a therapeutic primer on the long-term bond strengths of two etch-and-rinse adhesives to normal (ND) and caries-affected (CAD) dentin. Forty extracted human molars with coronal carious lesions, surrounded by normal dentin, were selected for this study. The flat surfaces of two types of dentin (ND and CAD) were prepared with a water-cooled high-speed diamond disc, then acidetched, rinsed and air-dried. In the control groups, the dentin was re-hydrated with distilled water, blot-dried and bonded with a three-step (Scotchbond Multi-Purpose-MP) or two-step (Single Bond 2-SB) etch-and-rinse adhesive. In the experimental groups, the dentin was rehydrated with 2% CHX (60 seconds), blot-dried and bonded with the same adhesives. Resin composite build-ups were made. The specimens were prepared for microtensile bond testing in accordance with the non-trimming technique, then tested either immediately or after six-months storage in artificial saliva. The data were analyzed by ANOVA/Bonferroni tests (alpha=0.05). CHX did not affect the immediate bond strength to ND or CAD (p>0.05). CHX treatment significantly lowered the loss of bond strength after six months as seen in the control bonds for ND (p<0.05), but it did not alter the bond strength of CAD (p>0.05). The application of NIP on CHX-treated ND or CAD produced bonds that did not change over six months of storage.

Growth hormone binding protein in normal and aneuploid pregnancy: a paradoxical decrease in trisomy 18

Objective To explore whether abnormalities in growth hormone binding protein (GHBP) may underlie the growth restriction associated with fetal aneuploidy. Design A retrospective casecontrol study. Setting Monash Medical Centre, Clayton, Victoria, Australia. Population Twenty-one trisomy 18, and 30 trisomy 21 pregnancies, and 170 chromosomally normal pregnancies at 15-18 weeks of gestation representing three to five controls per case matched for source, gestation and duration of storage. Methods GHBP was measured using a ligand immunofunctional assay. Results In the chromosomally normal pregnancies GHBP levels decreased slightly but significantly across the narrow gestational window studied. Compared with controls, levels of GHBP, expressed as median (95% CI) multiples of the median (MoM), in the trisomy 21 pregnancies were similar, 1.0 (0.92-1.39) MoM and 1.27 (1.04-1.50) MoM, respectively; P = 0.061 (Mann-Whitney CI test) but were significantly reduced in the trisomy 18 pregnancies, 0.68 (0.51-0.84) MoM; P = 0.0014 (Mann-Whitney U test). Conclusions These data suggest that decreased levels of maternal growth hormone binding protein, and by implication growth hormone receptor complement, may underlie the early severe growth restriction that is characteristic of trisomy 18.

Deletion of 8p: a report of a child with normal intelligence

The case is presented of a female infant with a distal deletion of 8p (8p23.1 --> pter) whose development was monitored over a 5-year period from 12 months of age. Although previous literature has suggested that 8p deletion is associated with mild to moderate intellectual disability, the child reported here has normal intelligence. Despite initial delays in gross motor and language skills, cognitive development (assessed with the Bayley Scales of Infant Development) and intellectual ability (measured on the Stanford-Binet Intelligence Scale) were within average range. It is argued that the small number of previous case reports may have created a misleading impression of intellectual development in individuals with distal deletions of 8p.

The ratio of messenger RNA levels of receptor activator of nuclear factor kappa B ligand to osteoprotegerin correlates with bone remodeling indices in normal human cancellous bone but not in osteoarthritis

skeletal disease. Bone remodeling is initiated by osteoclastic resorption followed by osteoblastic formation of new bone. Receptor activator of nuclear factor KB ligand (RANKL) is a newly described regulator of osteoclast formation and function, the activity of which appears to be a balance between interaction with its receptor RANK and with an antagonist binding protein osteoprotegerin (OPG). Therefore, we have examined the relationship between the expression of RANKL, RANK, and OPG and indices of bone structure and turnover in human cancellous bone from the proximal femur. Bone samples were obtained from individuals with osteoarthritis (OA) at joint replacement surgery and from autopsy controls. Histomorphometric analysis of these samples showed that eroded surface (ES/BS) and osteoid surface (OS/BS) were positively associated in both control (p < 0.001) and OA (p < 0.02), indicating that the processes of bone resorption and bone formation remain coupled in OA, as they are in controls. RANKL, OPG, and RANK messenger RNA, (mRNA) were abundant in human cancellous bone, with significant differences between control and OA individuals. In coplotting the molecular and histomorphometric data, strong associations were found between the ratio of RANKL/OPG mRNA and the indices of bone turnover (RANKL/OPG vs. ES/BS: r = 0.93, p < 0.001; RANKL/OPG vs. OS/BS: r = 0.80, p < 0.001). These relationships were not evident in trabecular bone from severe OA, suggesting that bone turnover may be regulated differently in this disease. We propose that the effective concentration of RANKL is related causally to bone turnover.

Determination of reference values for glucose tolerance, insulin tolerance, and insulin sensitivity tests in clinically normal cats

Objective-To determine reference values and test variability for glucose tolerance tests (GTT), insulin tolerance tests (ITT), and insulin sensitivity tests (IST) in cats, Animals-32 clinically normal cats. Procedure-GTT, ITT, and IST were performed on consecutive days. Tolerance intervals tie, reference values) were calculated as means +/- 2.397 SD for plasma glucose and insulin concentrations, half-life of glucose (T-1/2glucose), rate constants for glucose disappearance (K-glucose and K-itt), and insulin sensitivity index (S-l). Tests were repeated after 6 weeks in 8 cats to determine test variability. Results-Reference values for T-1/2glucose, K-glucose, and fasting plasma glucose and insulin concentrations during GTT were 45 to 74 minutes, 0.93 to 1.54 %/min, 37 to 104 mg/dl, and 2.8 to 20.6 muU/ml, respectively. Mean values did not differ between the 2 tests. Coefficients of variation for T-1/2glucose, K-glucose, and fasting plasma glucose and insulin concentrations were 20, 20, 11, and 23%, respectively. Reference values for K-itt were 1.14 to 7.3%/min, and for S-l were 0.57 to 10.99 x 10(-4) min/muU/ml. Mean values did not differ between the 2 tests performed 6 weeks apart, Coefficients of variation for K-itt and S-l were 60 and 47%, respectively. Conclusions and Clinical Relevance-GTT, ITT, and IST can be performed in cats, using standard protocols. Knowledge of reference values and test variability will enable researchers to better interpret test results for assessment of glucose tolerance, pancreatic beta -cell function, and insulin sensitivity in cats.

A soluble form of CD83 is released from activated dendritic cells and B lymphocytes, and is detectable in normal human sera

CD83 is an inducible glycoprotein expressed predominantly by dendritic cells (DC) and B lymphocytes. Expression of membrane CD83 (mCD83) is widely used as a marker of differentiated/ activated DC but its function and ligand(s) are presently unknown. We report the existence of a soluble form of CD83 (sCD83). Using both a sCD83-specific ELISA and Western blotting, we could demonstrate the release of sCD83 by mCD83(+) B cell and Hodgkin's disease-derived cell lines, but not mCD83(-) cells. Inhibition of de novo protein synthesis did not affect the release of sCD83 during short-term (2 h) culture of cell lines although mCD83 expression was significantly reduced, suggesting sCD83 is generated by the release of mCD83. Isolated tonsillar B lymphocytes and monocyte-derived DC, which are mCD83(low), released only low levels of sCD83 during culture. However, the differentiation/activation of these populations both up-regulated mCD83 and increased sCD83 release significantly. Analysis of sera from normal donors demonstrated the presence of low levels (121 +/- 3.6 pg/ml) of circulating sCD83. Further studies utilizing purified sCD83 and the analysis of sCD83 levels in disease may provide clues to the function and ligand(s) of CD83.

Detection and description of non-linear interdependence in normal multichannel human EEG data

Objectives: This study examines human scalp electroencephalographic (EEG) data for evidence of non-linear interdependence between posterior channels. The spectral and phase properties of those epochs of EEG exhibiting non-linear interdependence are studied. Methods: Scalp EEG data was collected from 40 healthy subjects. A technique for the detection of non-linear interdependence was applied to 2.048 s segments of posterior bipolar electrode data. Amplitude-adjusted phase-randomized surrogate data was used to statistically determine which EEG epochs exhibited non-linear interdependence. Results: Statistically significant evidence of non-linear interactions were evident in 2.9% (eyes open) to 4.8% (eyes closed) of the epochs. In the eyes-open recordings, these epochs exhibited a peak in the spectral and cross-spectral density functions at about 10 Hz. Two types of EEG epochs are evident in the eyes-closed recordings; one type exhibits a peak in the spectral density and cross-spectrum at 8 Hz. The other type has increased spectral and cross-spectral power across faster frequencies. Epochs identified as exhibiting non-linear interdependence display a tendency towards phase interdependencies across and between a broad range of frequencies. Conclusions: Non-linear interdependence is detectable in a small number of multichannel EEG epochs, and makes a contribution to the alpha rhythm. Non-linear interdependence produces spatially distributed activity that exhibits phase synchronization between oscillations present at different frequencies. The possible physiological significance of these findings are discussed with reference to the dynamical properties of neural systems and the role of synchronous activity in the neocortex. (C) 2002 Elsevier Science Ireland Ltd. All rights reserved.

Nuclear RelB(+) cells are found in normal lymphoid organs and in peripheral tissue in the context of inflammation, but not under normal resting conditions

Differentiated dendritic cells (DC) have been identified by the presence of nuclear RelB (nRelB) and HLA-DR, and the absence of CD20 or high levels of CD68, in lymph nodes and active rheumatoid arthritis synovial tissue. The current studies aimed to identify conditions in which nRelB is expressed in human tissues, by single and double immunohistochemistry of formalin-fixed peripheral and lymphoid tissue. Normal peripheral tissue did not contain nRelB(+) cells. nRelB(+) DC were located only in T- or B-cell areas of lymphoid tissue associated with normal organs or peripheral tissues, including tonsil, colon, spleen and thymus, or in association with T cells in inflamed peripheral tissue. Inflamed sites included skin delayed-type hypersensitivity reaction, and a wide range of tissues affected by autoimmune disease. Nuclear RelB(+) -HLA-DR- follicular DC were located in B-cell follicles in lymphoid organs and in lymphoid-like follicles of some tissues affected by autoimmune disease. Lymphoid tissue T-cell areas also contained nRelB(-) -HLA-DR+ cells, some of which expressed CD123 and/or CD68. Nuclear RelB(+) cells are found in normal lymphoid organs and in peripheral tissue in the context of inflammation, but not under normal resting conditions.

Bishadowing and hyperbolicity

Shadowing of a dynamical system is often used to justify the validity of computer simulations of the system, and in numerical calculations an inverse form of the shadowing concept is also of some interest. In this paper we characterize the notion of shadowing in terms of stability, and express the notion of hyperbolicity using the concept of inverse shadowing.