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991.
Background: Fibroblasts are now seen as active components of the immune response because these cells express Toll‐like receptors (TLRs), recognize pathogen‐associated molecular patterns, and mediate the production of cytokines and chemokines during inflammation. The innate host response to lipopolysaccharide (LPS) from Porphyromonas gingivalis is unusual inasmuch as different studies have reported that it can be an agonist for Toll‐like receptor 2 (TLR2) and an antagonist or agonist for Toll‐like receptor 4 (TLR4). This study investigates and compares whether signaling through TLR2 or TLR4 could affect the secretion of interleukin (IL)‐6, IL‐8, and stromal derived factor‐1 (SDF‐1/CXCL12) in both human gingival fibroblasts (HGF) and human periodontal ligament fibroblasts (HPDLF). Methods: After small interfering RNA‐mediated silencing of TLR2 and TLR4, HGF and HPDLF from the same donors were stimulated with P. gingivalis LPS or with two synthetic ligands of TLR2, Pam2CSK4 and Pam3CSK4, for 6 hours. IL‐6, IL‐8, and CXCL12 mRNA expression and protein secretion were evaluated by quantitative polymerase chain reaction and enzyme‐linked immunosorbent assay, respectively. Results: TLR2 mRNA expression was upregulated in HGF but not in HPDLF by all the stimuli applied. Knockdown of TLR2 decreased IL‐6 and IL‐8 in response to P. gingivalis LPS, or Pam2CSK4 and Pam3CSK4, in a similar manner in both fibroblasts subpopulations. Conversely, CXCL12 remained unchanged by TLR2 or TLR4 silencing. Conclusion: These results suggest that signaling through TLR2 by gingival and periodontal ligament fibroblasts can control the secretion of IL‐6 and IL‐8, which contribute to periodontal pathogenesis, but do not interfere with CXCL12 levels, an important chemokine in the repair process.  相似文献   
992.
Background: Anatomic variations of the maxillary sinus determine the degree of difficulty in performing sinus augmentation. Whereas some variations, e.g., the septum and morphology of the sinus, have been extensively studied, the structure of the medial wall has never been investigated. The aims of this study are to measure the location and angulation of the palatonasal recess (PNR) on the medial wall and identify risk sites that are related to the shape of the PNR. Methods: Cone‐beam computed tomography (CBCT) scans were screened from the University of Michigan School of Dentistry database. Edentulous sites with <10 mm between the floor of the maxillary sinus and the alveolar crest were selected. The residual ridge height (RH), the distance between the PNR and the alveolar crest, and the angulation of the PNR were measured on the selected sagittal planes. The percentage of sites (risk sites) with recesses that were <90°and <15 mm from the alveolar crest was calculated. The PNR location and angulation were compared among premolar and molar edentulous sites. Results: Two hundred seventy‐four sites were studied. The mean ± SE PNR location was 14.2 ± 2.8 mm, 13.1 ± 2.2 mm, and 12.5 ± 2.5 mm for the second premolar, first molar, and second molar sites, respectively, with significant differences between the second premolar and second molar sites. The mean PNR angulation was 109.8° ± 25.3°, 121.6° ± 22.1°, and 144.9° ± 23.1° in the corresponding sites, with significant differences among the site groups. The respective percentages of risk sites were 15%, 8.2%, and 2.4% in the second premolar, first molar, and second molar sites. Conclusions: Maxillary sinuses with acute‐angled PNRs might present a challenge for performing sinus augmentation. Therefore, this anatomic structure should be carefully evaluated.  相似文献   
993.
Background: This meta‐analysis of prospective clinical trials was conducted to determine the effects of dental implant length and width on implant survival rate of short (<10 mm) implants. Methods: An electronic search of the PubMed database for relevant studies published in English from November 1998 to March 2012 was performed. Selected studies were randomized clinical trials, human clinical trials, or prospective trials with a clear aim of investigating the success or survival rate of short (<10 mm) implants. Results: Eight studies fulfilled the inclusion criteria and were subsequently analyzed. A total of 525 short (<10 mm) dental implants were analyzed, of which 253 were 3.5 mm in diameter (48.19%), 151 were 4.0 mm (28.76%), 90 were 4.1 mm (17.14%), 21 were 4.8 mm (4%), and 10 were 5.1 mm (1.9%). All implants included in this meta‐analysis had a follow‐up period of 12 to 72 months. The included studies reported on the survival rate and diameter of the implants. Six of the studies used “short implants” (7 to 9 mm), and the remaining were classified as “extra‐short implants” (≤6 mm). Five‐year estimated failure rates were 1.61% and 2.92%, respectively, for extra‐short and short implants (z = ?3.49, P <0.001, 95% confidence interval = 0.51% to 4.10%). Furthermore, it was found that the wider the implant, the higher the failure rate (estimated failure rate = 2.36%, 95% confidence interval = 1.07% to 5.23%). Conclusions: Neither implant length nor width seemed to significantly affect the survival rate of short implants (<10 mm). Nonetheless, further well‐designed randomized clinical trials are needed to confirm these findings.  相似文献   
994.
995.
This study aimed to examine perceptions of the working alliance in a sample of Spanish patients and therapists. The alliance was measured after the third and tenth psychotherapy sessions using patient and therapist versions of the Spanish adaptation of the Working Alliance Inventory (WAI). After both sessions, correlations between the patients’ and therapists’ ratings, both of total alliance and of the various dimensions of the alliance, were moderate at best. Moreover, after the third psychotherapy session, patients’ scores for the total alliance and the Goal and Task subscales were significantly higher than the scores from their therapists in these dimensions. Following the tenth session, patient ratings exceeded those of their therapists only on the Task subscale. Finally, in contrast to the ratings of patients, therapists’ alliance ratings increased significantly between the third and tenth sessions of psychotherapy. Certain recommendations are presented to improve the study of patient and therapist perceptions of the working alliance and to increase the convergence between them with regard to this central treatment variable.  相似文献   
996.
Although lesional, neuroimaging, and brain stimulation studies have provided an insight into the neural mechanisms of judgement and decision-making, all these works focused on the cerebral cortex, without investigating the role of subcortical structures such as the basal ganglia. Besides being an effective therapeutic tool, deep brain stimulation (DBS) allows local field potential (LFP) recordings through the stimulation electrodes thus providing a physiological "window" on human subcortical structures. In this study we assessed whether subthalamic nucleus LFP oscillations are modulated by processing of moral conflictual, moral nonconflictual, and neutral statements. To do so, in 16 patients with Parkinson's disease (8 men) bilaterally implanted with subthalamic nucleus (STN) electrodes for DBS, we recorded STN LFPs 4 days after surgery during a moral decision task. During the task, recordings from the STN showed changes in LFP oscillations. Whereas the 14--30 Hz band (beta) changed during the movement executed to perform the task, the 5--13 Hz band (low-frequency) changed when subjects evaluated the content of statements. Low-frequency band power increased significantly more during conflictual than during nonconflictual or neutral sentences. We conclude that STN responds specifically to conflictual moral stimuli, and could be involved in conflictual decisions of all kinds, not only those for moral judgment. LFP oscillations provide novel direct evidence that the neural processing of conflictual decision-making spreads beyond the cortex to the basal ganglia and encompasses a specific subcortical conflict-dependent component.  相似文献   
997.
Down syndrome (DS) is the most frequent live-born autosomal aneuploidy in humans. Scanty data on the craniofacial phenotype of African subjects with DS have been published so far. We wanted to detail the morphologic characteristics of the ears in north Sudanese subjects with DS. The three-dimensional coordinates of 13 soft-tissue landmarks on the ears were obtained using a laser scanner in 64 north Sudanese subjects with DS aged 4 to 34 years and in 682 sex- and age-matched control subjects. From the landmarks, left and right linear distances (ear width and length), ratios (ear width-to-ear length), areas (ear area), angles (angle of the auricle vs the facial midplane), and the three-dimensional symmetry index were calculated. Distances, angles, areas, and ratios were computed. Subject and reference data were compared by computing z scores and calculating Student t tests. Ear width, length, and area were significantly (Student t test, P < 0.001) smaller in the subjects with DS than in the reference subjects. On the right side of the face, the subjects with DS had larger ear width-to-ear length ratios and larger angles of the auricle versus the facial midplane than the reference subjects. The three-dimensional symmetry index was significantly larger in the reference subjects. In conclusion, ear dimensions, position, and shape significantly differed in subjects with DS when compared with sex-, age-, and ethnic group-matched control subjects.  相似文献   
998.
The case report describes the multidisciplinary treatment of a 25-year-old male patient with a Class III malocclusion. Anterior and bilateral posterior crossbites were present. To correct the posterior crossbite a surgically assisted rapid maxillary expansion was performed. The significant three dimensional skeletal discrepancy was solved in a second phase with a surgical advancement of the maxilla. Functional and aesthetic occlusion in an improved facial profile was achieved with an interdisciplinary treatment that included orthodontic treatment, maxillofacial and periodontal surgery, and direct composite restorations.  相似文献   
999.
1000.
The selection of T lymphocytes in the thymus and their activation upon the encounter with foreign antigens in the periphery require the aggregation and signals of the Tcell receptor (TcR)/CD3 complex and several surface molecules termed coreceptors (notably CD4 or CD8 and CD45). The spatial arrangement and interactions of the different molecules in the resulting multimolecular recognition structure are mostly unknown. Here we report, from studies on a healthy human CD3γ deficiency, that the lack of the CD3γ component of the TcR/CD3 complex is associated with a long-term severe defect of peripheral blood CD4+CD45RA+ and CD8+ lymphocytes, whereas CD4+CD45RO+, B and natural killer lymphocytes are unaffected. These results suggest that the CD3y site of the TcR/CD3 complex is required for the peripheral representation of certain Tcell types.  相似文献   
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