Occurrence of malocclusion and need of orthodontic treatment in early mixed dentition

This study analyzed the occlusions of 489 children at the onset of the mixed dentition period (mean age 5.1 years, range 4.0-7.8 years). These children participate in an ongoing clinical trial that is investigating the effects of orthodontic intervention in the early mixed dentition. The aim was to report the occlusal findings at the baseline. The frequencies of mesial step, flush terminal plane, and distal step were 19.1%, 47.8%, and 33.1%, respectively. The canine relationship was Class I in 46.1%, Class II in 52.4%, and Class III in 1.5% of the sides examined. An asymmetrical canine relationship was found in 30.1% of the children, significantly more often on the right side than on the left (P <.001). Overjet ranged from -2 to +10 mm with a mean of 2.9 mm. Overbite ranged from -5 to +8 mm with a mean of 2.8 mm. Excessive (> or =4 mm) overjet was found in 26.7% and overbite in 33.8% of the children; in 15.5% of the children, both variables were 4 mm or more. Anterior crowding was detected in the maxillary arch in 11.6% and in the mandibular arch in 38.9% of the children. Girls showed mandibular crowding more often than boys (P <.01). A posterior crossbite was found in 7.5% of the children, unilaterally in 6.4% and bilaterally in 1.1%. Scissors-bite was detected in 1.1% and an anterior crossbite in 2.2% of the children. The mean maximal opening was 40.3 mm. Joint sounds were registered in 5.2% of the children. The prevalence of malocclusion was between 67.7% and 92.7%, depending on the values of unacceptable parameters used for each occlusal characteristic.     

The effect of a very low-calorie diet-induced weight loss on the severity of obstructive sleep apnoea and autonomic nervous function in obese patients with obstructive sleep apnoea syndrome

The aim of this study was to examine the effect of a very low-calorie diet (VLCD)-induced weight loss on the severity of obstructive sleep apnoea (OSA), blood pressure and cardiac autonomic regulation in obese patients with obstructive sleep apnoea syndrome (OSAS). A total of 15 overweight patients (14 men and one woman, body weight 114 ± 20 kg, age 52 ± 9 years, range 39–67 years) with OSAS were studied prospectively. They were advised to follow a 2·51–3·35 MJ (600–800 kcal) diet daily for a 3-month period. In the beginning of the study, the patients underwent nocturnal sleep studies, autonomic function tests and 24-h electrocardiograph (ECG) recording. In addition, 15 age-matched, normal-weight subjects were studied. They underwent the Valsalva test, the deep-breathing test and assessment of heart rate variability at rest. The sleep studies and autonomic function tests were repeated after the weight loss period. There was a significant reduction in weight (114 ± 20 kg to 105 ± 21 kg, P<0·001), the weight loss being 9·2 ± 4·0 kg (range 2·3–19·5 kg). This was associated with a significant improvement in the oxygen desaturation index (ODI4) during sleep (31 ± 20–19 ±18, P<0·001). Before the weight loss the OSAS patients had significantly higher blood pressure (150 ± 18 vs. 134 ± 20, P<0·05, for systolic blood pressure, 98 ± 10 vs. 85 ± 13, P<0·05, for diastolic blood pressure) and heart rate (67 ± 10 beats min^?1 vs. 60 ± 13, P<0·05) at rest than the control group. They had also lower baroreflex sensitivity (4·7 ± 2·8 ms mmHg^?1 vs. 10·8 ± 7·1 ms mmHg^?1, P<0·01). During the weight reduction, the blood pressure declined significantly, and the baroreflex sensitivity increased by 49%. In conclusion, our experience shows that weight loss with VLCD is an effective treatment for OSAS. Weight loss improved significantly sleep apnoea and had favourable effects on blood pressure and baroreflex sensitivity that may have prognostic implications.     

Muscle function in monozygotic female twin pairs discordant for hormone replacement therapy

Introduction: Postmenopausal monozygotic twin pairs discordant for hormone replacement therapy (HRT) provide an advantageous study design controlling for genetic background for elucidating the relationships between aging, sex hormone levels, muscle strength, contractile capacity, and fatigability. Methods: Thirteen postmenopausal monozygotic twin pairs discordant for HRT were measured for maximal voluntary torque (MVC) and twitch characteristics using electrical stimulation before and after intermittent dynamic plantarflexor exercise until exhaustion. Results: Peak twitch torque was 32% higher in HRT users than in their non‐HRT, genetically identical sisters (P = 0.002), but MVC did not differ. There were no differences in the activation level or twitch time characteristics between the co‐twins. Fatigue caused decreases in MVC (P = 0.001), twitch torque (P = 0.001), time to peak (P = 0.013), and half‐relaxation time (P = 0.001) similarly in HRT users and non–HRT users. Conclusion: In early postmenopausal women, involuntary but not voluntary force‐generating mechanisms of the plantarflexors are augmented by the use of HRT. Muscle Nerve, 2011     

Probiotic bacteria affect the composition of salivary pellicle and streptococcal adhesion in vitro

Introduction:  The use of probiotic bacteria is increasing worldwide and at least some of them can transiently colonize the oral cavity. Several studies have shown that probiotic bacteria, which are often thought of in relation only to intestinal health, can also affect the oral ecology, but the mechanisms for this are largely unknown. The aim of this study was to investigate in vitro if the probiotic bacteria used in commercial products affect the protein composition of the salivary pellicle and the adherence of other oral bacteria.
Methods:  Salivary pellicle on hydroxyapatite and the adhesion of two oral streptococci, Streptococcus mutans and Streptococcus gordonii , were used as a model.
Results:  Probiotic bacteria that bound to saliva-coated hydroxyapatite reduced the adhesion of S. mutans but the inhibitory effect on the adherence of S. gordonii was weaker. Salivary pellicle protein composition was modified by all the strains tested. The modifications in the pellicle affected the adherence of S. mutans but not of S. gordonii . Two of the proteins missing from the pellicles made of saliva-treated with the probiotic bacteria were identified as salivary agglutinin gp340 and salivary peroxidase. All bacterial strains bound salivary agglutinin gp340. The ability of the probiotic bacteria to degrade peroxidase was demonstrated with purified bovine lactoperoxidase and two of the probiotic strains.
Conclusion:  This in vitro study showed that probiotic strains used in commercial products may affect the oral ecology by specifically preventing the adherence of other bacteria and by modifying the protein composition of the salivary pellicle.     

Extracellular superoxide dismutase in pulmonary fibrosis

Disruption of the oxidant/antioxidant balance in the lung is thought to be a key step in the development of many airway pathologies. Hence, antioxidant enzymes play key roles in controlling or preventing pulmonary diseases related to oxidative stress. The superoxide dismutases (SOD) are a family of enzymes that play a pivotal role protecting tissues from damage by oxidant stress by scavenging superoxide anion, which prevents the formation of other more potent oxidants such as peroxynitrite and hydroxyl radical. Extracellular SOD (EC-SOD) is found predominantly in the extracellular matrix of tissues and is ideally situated to prevent cell and tissue damage initiated by extracellularly produced ROS. EC-SOD has been shown to be protective in several models of interstitial lung disease, including pulmonary fibrosis. In addition, alterations in EC-SOD expression are also present in human idiopathic pulmonary fibrosis (IPF). This review discusses EC-SOD regulation in response to pulmonary fibrosis in animals and humans and reviews possible mechanisms by which EC-SOD may protect against fibrosis.     

Decreased expression of antioxidant enzymes is associated with aggressive features in ependymomas

The purpose of this study was to investigate the relationship between antioxidant enzyme expression and clinicopathological features in 67 ependymal tumors. We included into the analysis antioxidant enzymes (AOEs) and related proteins, such as, manganese superoxide dismutase (MnSOD), gammaglutamylcysteine synthetase catalytic and regulatory subunits (GLCL-C and GLCL-R), thioredoxin (Trx) and thioredoxin reductase (TrxR). Their expression was studied in 46 primary (10 grade I, 30 grade II and 6 grade III) and 21 recurrent (3 grade I, 12 grade II and 6 grade III) tumors. Immunoreactivity for MnSOD was found in 87%, GLCL-C in 74%, GLCL-R in 89%, Trx in 72%, TrxR in 54%, of primary tumors. Lower GLCL-C and GLCL-R expression was associated with higher tumor grade (P = 0.047 and 0.049, respectively). MnSOD, GLCL-C and TrxR expressions were significantly higher in tumors located in the spinal cord compared to those in the brain (P = 0.044, 0.046 and 0.004, respectively). In the primary tumors Trx-positivity was found to correlate significantly with patient survival. In univariate survival analysis patients whose tumors did not express Trx had shorter survival (P = 0.045) and there was even more significant association (P = 0.011) when only adults were included in the analysis (in the total material median follow-up time of Trx-positive tumors was 9.7 years and of Trx-negative 5.4 years). The results indicate that AOEs have several biological functions in ependymal tumors. Trx had important prognostic value: all adults with Trx-positive tumors were alive at follow-up (median 7.8 years).     

Lactoperoxidase inhibits glucosyltransferases from Streptococcus mutans in vitro

This study examines the possible effect of the antimicrobial peroxidase system on the activity of streptococcal glucosyltransferases B, C and D (GtfB, GtfC and GtfD), either in solution (GtfB and GtfC) or when adsorbed to hydroxyapatite (GtfC and GtfD) at pH 6.5. The lactoperoxidase (LP) system (LP, H(2)O(2), SCN(-)) had no effect on the activity of dissolved GtfC, but the activity of dissolved GtfB was enhanced. The LP system, however, strongly inhibited the activities of both GtfC and GtfD in their adsorbed form. LP enzyme, without its substrates, inhibited all three Gtf enzymes: GtfB and GtfC in concentrations between 10 and 100 microg/ml in liquid phase and adsorbed GtfC and GtfD in concentrations between 25 and 50 microg/ml. This inhibition was in part abolished in liquid phase, but not in solid phase, if the substrates of LP were added. This study shows that the lactoperoxidase system can exert inhibitory activity against streptococcal Gtfs without generating oxidizing agents.     

COL1A1 Sp1 polymorphism associates with bone density in early puberty

Optimal acquisition of bone mass in puberty is a key determinant of the lifetime risk of osteoporosis and has a strong genetic basis. We investigated the relationship between the COL1A1 Sp1 polymorphism and BMD in early puberty, and how the genotypes relate to bone size and geometry as well as bone turnover and material properties in 247 10- to 13-year-old girls. Bone properties were measured using DXA, pQCT, and ultrasound. Also, serum P1NP, OC, B-ALP, and TRACP 5b were assessed. Our results showed that girls with the TT genotype had significantly lower BMC and BMD of the total body, lumbar spine, and proximal femur, as well as BUA at the calcaneus, than those with the GT and GG genotype. They also had significantly lower B-ALP, as well as P1NP/TRACP 5b and (OC + B-ALP)/TRACP 5b, compared to the others. These findings indicate that the COL1A1 polymorphism is associated with low bone properties in early puberty and suggest a possible physiological effect on collagen metabolism and bone turnover. This information may contribute to the identification of children at risk for suboptimal acquisition of peak bone mass and may ultimately be of value in the planning of early preventive strategies for osteoporosis.     

Antioxidant enzymes in oligodendroglial brain tumors: association with proliferation, apoptotic activity and survival

Summary Purpose of the study was to investigate the relationship between antioxidant enzyme expression and clinicopathological features in oligodendroglial tumors. The expression of antioxidant enzymes and related proteins (AOEs),␣manganese superoxide dismutase (MnSOD), thioredoxin (Trx), thioredoxin reductase (TrxR) and gammaglutamylcysteine synthetase catalytic and regulatory subunits (GLCL-C and GLCL-R), was studied in 85 oligodendroglial tumors. The material included 71 primary (43 grade II and 28 grade III) and 14 recurrent (6 grade II and 8 grade III) tumors. Fifty-seven cases were pure oligodendrogliomas and 28 were mixed oligoastrocytomas. Immunoreactivity for MnSOD was found in 89%, Trx in 29%, TrxR in 76%, GLCL-C in 70% and GLCL-R in 68% of cases. Increased Trx expression was associated with higher tumor grade, cell proliferation and apoptosis (P=0.006, P=0.001 and P=0.003, Mann–Whitney test). Pure oligodendrogliomas showed more intense staining than oligoastrocytomas, especially for MnSOD (P=0.002, Mann–Whitney test). In the total series Trx was associated with poor prognosis in univariate survival analysis (P=0.0343, log-rank test) and furthermore in Cox multivariate analysis (P=0.009) along with age (P=0.002). The results suggest that the expression of Trx has a correlation to patient outcome and that there may be some association between AOEs, like MnSOD and Trx, and clinicopathological features of oligodendrogliomas.