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991.

Background

Adolescence is a period of life marked by important changes: physical growth and development, emotional changes, the search for one’s own identity and an evolving role in society. Most of these changes will have an impact on health, also with respect of the oral cavity.

Aims

This contribution aims to give an overview of the problems faced by the adolescent (in general and more specifically related to the oral cavity) and the challenges for the dental professional (specific oral problems, challenge of communicating with adolescent patients). The main aim is to provide some useful hints for the follow-up of adolescent patients in everyday dental practice.

Results

Specific oral health concerns in adolescents will include changes in caries risk, dental erosion, trauma, periodontal disease, tooth positioning and malocclusion, emergence of wisdom teeth and so on. On top of this, adolescents are interested in tooth whitening and oral piercings, and they will experiment with tobacco, alcohol and drugs. All of these can further endanger oral health. The dental professional will be faced with a variety of these problems and will need to provide preventive and therapeutic solutions adapted to the specific situation of the adolescent. This necessitates some insight into the world of the adolescent of today. This is especially true since it is known that oral health-related behaviours (e.g. brushing habits, smoking and so on) developed during adolescence are carried over into adulthood and continue to influence (oral) health later in life. This underlines the need for intervention in this age group. However, in this period of life everything is questioned and communication between adolescents and adults is often dramatic. Although the specific effectiveness of following up adolescent patients is recognised, it is remarkable how poor dental literature is with regard to this topic.  相似文献   
992.
The voltage-gated potassium channel Kv1.5 is one of the key regulators of membrane potential repolarization in human atrial myocytes and is considered a potential drug target to treat atrial fibrillation. In this study we sought to determine molecular mechanism of action of DPO-1, a diphenylphosphine oxide derivative recently shown to terminate experimental atrial arrhythmia without affecting ventricular refractory period. In addition, we provided similar analysis for additional two small molecule blockers, representing different structural classes: cyclohexanones (PAC) and nor-triterpenoids (correolide). To rapidly identify the residues within the Kv1.5 channel critical for blocking activity of these molecules, two functional high-throughput ion channel assays were employed together with site-directed mutagenesis. Our study revealed that the residues critical for blocking activity of for DPO-1 include T480, localized at the outer mouth of the pore, and two residues along S6 helix: V505 and I508. The overlapping site was identified for PAC and included residues T480 and V505. In contrast to DPO-1, the I508A mutation resulted in only a modest reduction in the block of Kv1.5 by PAC (9-fold). Correolide, the largest molecule examined, made widespread interactions along the entire length of the pore (from T480 to V516). In summary, we have identified multiple residues involved in forming high affinity binding site for Kv1.5 blockers. Similar approaches of high-throughput ion channel technologies, combined with site-directed mutagenesis, may allow for parallel, rapid and accurate analysis of ion channel interactions with multiple compounds and could facilitate the design of more potent and selective ion channel blockers.  相似文献   
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Although acute lung injury contributes significantly to critical illness, resolution often occurs spontaneously via activation of incompletely understood pathways. We recently found that mechanical ventilation of mice increases the level of pulmonary adenosine, and that mice deficient for extracellular adenosine generation show increased pulmonary edema and inflammation after ventilator-induced lung injury (VILI). Here, we profiled the response to VILI in mice with genetic deletions of each of the 4 adenosine receptors (ARs) and found that deletion of the A2BAR gene was specifically associated with reduced survival time and increased pulmonary albumin leakage after injury. In WT mice, treatment with an A2BAR-selective antagonist resulted in enhanced pulmonary inflammation, edema, and attenuated gas exchange, while an A2BAR agonist attenuated VILI. In bone marrow–chimeric A2BAR mice, although the pulmonary inflammatory response involved A2BAR signaling from bone marrow–derived cells, A2BARs located on the lung tissue attenuated VILI-induced albumin leakage and pulmonary edema. Furthermore, measurement of alveolar fluid clearance (AFC) demonstrated that A2BAR signaling enhanced amiloride-sensitive fluid transport and elevation of pulmonary cAMP levels following VILI, suggesting that A2BAR agonist treatment protects by drying out the lungs. Similar enhancement of pulmonary cAMP and AFC were also observed after β-adrenergic stimulation, a pathway known to promote AFC. Taken together, these studies reveal a role for A2BAR signaling in attenuating VILI and implicate this receptor as a potential therapeutic target during acute lung injury.  相似文献   
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BACKGROUND: The 7-item Generalized Anxiety Disorder Scale (GAD-7) is a practical self-report anxiety questionnaire that proved valid in primary care. However, the GAD-7 was not yet validated in the general population and thus far, normative data are not available. OBJECTIVES: To investigate reliability, construct validity, and factorial validity of the GAD-7 in the general population and to generate normative data. RESEARCH DESIGN: Nationally representative face-to-face household survey conducted in Germany between May 5 and June 8, 2006. SUBJECTS: Five thousand thirty subjects (53.6% female) with a mean age (SD) of 48.4 (18.0) years. MEASURES: The survey questionnaire included the GAD-7, the 2-item depression module from the Patient Health Questionnaire (PHQ-2), the Rosenberg Self-Esteem Scale, and demographic characteristics. RESULTS: Confirmatory factor analyses substantiated the 1-dimensional structure of the GAD-7 and its factorial invariance for gender and age. Internal consistency was identical across all subgroups (alpha = 0.89). Intercorrelations with the PHQ-2 and the Rosenberg Self-Esteem Scale were r = 0.64 (P < 0.001) and r = -0.43 (P < 0.001), respectively. As expected, women had significantly higher mean (SD) GAD-7 anxiety scores compared with men [3.2 (3.5) vs. 2.7 (3.2); P < 0.001]. Normative data for the GAD-7 were generated for both genders and different age levels. Approximately 5% of subjects had GAD-7 scores of 10 or greater, and 1% had GAD-7 scores of 15 or greater. CONCLUSIONS: Evidence supports reliability and validity of the GAD-7 as a measure of anxiety in the general population. The normative data provided in this study can be used to compare a subject's GAD-7 score with those determined from a general population reference group.  相似文献   
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Galloway-Mowat syndrome (GMS) is a rare autosomal recessive disorder characterized by early onset nephrotic syndrome and microcephaly with various anomalies of the central nervous system. GMS likely represents a heterogeneous group of disorders with hitherto unknown genetic etiology. The clinical phenotype to some extent overlaps that of Pierson syndrome (PS), which comprises congenital nephrotic syndrome and distinct ocular abnormalities but which may also include neurodevelopmental deficits and microcephaly. PS is caused by mutations of LAMB2, the gene encoding laminin beta2. We hypothesized that GMS might be allelic to PS or be caused by defects in proteins that interact with laminin beta2. In a cohort of 18 patients with GMS or a GMS-like phenotype we therefore analyzed the genes encoding laminin beta2 (LAMB2), laminin alpha5 (LAMA5), alpha3-integrin (ITGA3), beta1-integrin (ITGB1) and alpha-actinin-4 (ACTN4), but we failed to find causative mutations in these genes. We inferred that LAMA5, ITGA3, ITGB1, and ACTN4 are not directly involved in the pathogenesis of GMS. We excluded LAMB2 as a candidate gene for GMS. Further studies are required, including linkage analysis in families with GMS to identify genes underlying this disease.  相似文献   
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