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81.
Fienitz T Schwarz F Ritter L Dreiseidler T Becker J Rothamel D 《Clinical oral implants research》2012,23(7):882-887
Objective: To assess the accuracy of cone‐beam computed tomography (CBCT) in terms of buccal bone‐wall configuration and peri‐implant bone defect regeneration after guided bone regeneration (GBR). Material and methods: Titanium implants were inserted into standardized box‐shaped defects in the mandible of 12 foxhounds. Defects of one side were augmented following the principle of GBR, while the other side was left untreated. Radiological evaluation was performed using CBCT and compared with histomorphometrical measurements of the respective site serving as a validation method. Results: Non‐augmented control sites providing a horizontal bone width (BW) of<0.5 mm revealed a significantly lower accuracy between the radiological and the histological evaluation of the buccal defect depth (1.93 ± 1.59 mm) compared with the group providing a BW of >0.5 mm (0.7 ± 0.7 mm) (P<0.05, Mann–Whitney U‐test). In GBR‐treated defects, the subgroup <0.5 mm (1.49 ± 1.29 mm) revealed a significantly higher difference between CBCT and histology compared with >0.5 mm (0.82 ± 1.07) (P>0.05, Mann–Whitney U‐test). However, a radiological discrimination between original bone, integrated and non‐integrated bone substitute material was not reliable. Additionally, it was found that a minimum buccal BW of 0.5 mm was necessary for the detection of bone in radiology. Conclusion: The evaluation of peri‐implant bone defect regeneration by means of CBCT is not accurate for sites providing a BW of <0.5 mm. Moreover, a safe assessment of the success of the GBR technique is not possible after the application of a radiopaque bone substitute material. To cite this article: Fienitz T, Schwarz F, Ritter L, Dreiseidler T, Becker J, Rothamel D. Accuracy of cone beam computed tomography in assessing peri‐implant bone defect regeneration: a histologically controlled study in dogs.Clin. Oral Impl. Res. 23 , 2012; 882–887.doi: 10.1111/j.1600‐0501.2011.02232.x 相似文献
82.
Freudlsperger C Kurth R Werner MK Hoffmann J Reinert S 《Oral and maxillofacial surgery》2012,16(1):79-82
Background
Although metastatic carcinoma is the most common malignant tumor of the bone, less than 1% of all metastatic bone lesions are presented in the maxillofacial area. As the mandibular body is the most frequent localization, metastasis to the mandibular condyle is extremely rare.Case report
This report describes a rare case of prostate carcinoma metastatic to the mandibular condyle in a 75-year old man, who was referred because of persistent pain in the temporomandibular joint (TMJ) region and a limitation of opening, initially misdiagnosed and treated as temporomandibular disorder (TMD). Histopathological examination confirmed the suspected metastasis of prostate carcinoma and local radiation therapy was performed.Discussion
TMD represent a diagnostic challenge and sometimes an interdisciplinary approach is required to prevent a delay of the correct treatment. Metastatic cancer should be included in the differential diagnosis of TMD, especially in patients with a malignant disease. 相似文献83.
84.
Milian M Teufel P Honegger J Gallwitz B Schnauder G Psaras T 《Clinical endocrinology》2012,76(6):851-860
Objective To develop a disease‐specific questionnaire for Cushing’s disease (CD), the Tuebingen Cushing’s disease quality of life inventory (Tuebingen CD‐25). Methods Sources for item generation consisted of technical literature, interviews with patients and the rating of neurosurgeons, endocrinologists and a neuropsychologist. A preliminary inventory with 64 items was handed out to 63 CD patients. Twenty‐eight patients filled out the questionnaire preoperative, the remaining 35 patients evaluated their health‐related quality of life (HRQoL) retrospectively. Item reduction and scale generation followed the principles of classical test theory. Validation was performed with the WHOQoL‐BREF. Results The final version of the Tuebingen CD‐25 contained 25 items, showed high reliability (Cronbach’s alpha = 0·93) and validity (r = ?0·65) and includes the subdomains Depression, Sexual Activity, Environment, Eating Behaviour, Bodily Restrictions and Cognition. The retrospective rating of the Tuebingen CD‐25 showed similar results compared to the pretreatment group. We found a non‐linear correlation between the Tuebingen CD‐25 scores and patients’ age, younger (21–30 years) and middle‐aged (51–60 years) patients having inferior HRQoL than patients between 31 and 50 years and older than 61 years. Preoperative 24 h urinary free cortisol (UFC) levels correlated significantly with the subscale Cognition and only marginally failed significance level for the subscale Eating Behaviour, while preoperative cortisol and ACTH levels did not correlate with any scale. Conclusion The Tuebingen CD‐25 is a valid and reliable instrument to evaluate HRQoL in CD. Based on impairment of HRQoL for the different subdimensions, specific support can be offered to the patients. 相似文献
85.
86.
Abdel-Wahab O Pardanani A Bernard OA Finazzi G Crispino JD Gisslinger H Kralovics R Odenike O Bhalla K Gupta V Barosi G Gotlib J Guglielmelli P Kiladjian JJ Noel P Cazzola M Vannucchi AM Hoffman R Barbui T Thiele J Van Etten RA Mughal T Tefferi A 《American journal of hematology》2012,87(5):562-568
Immediately after the annual scientific meeting of the American Society of Hematology (ASH), a select group of clinical and laboratory investigators in myeloproliferative neoplasms (MPN) is summoned to a post-ASH conference on chronic myeloid leukemia and the BCR-ABL1-negative MPN. The 6th such meeting occurred on December 13–14,2011, in La Jolla, California, USA, under the direction of its founder,Dr. Tariq Mughal. The current document is the first of two reports on this post-ASH event and summarizes the most recent preclinical and clinical advances in polycythemia vera, essential thrombocythemia,and primary myelofibrosis. 相似文献
87.
Tim Klucken Nina Alexander Jan Schweckendiek Christian J. Merz Sabine Kagerer Roman Osinsky Bertram Walter Dieter Vaitl Juergen Hennig Rudolf Stark 《Social cognitive and affective neuroscience》2013,8(3):318-325
Fear learning is a crucial process in the pathogeneses of psychiatric disorders, which highlights the need to identify specific factors contributing to interindividual variation. We hypothesized variation in the serotonin transporter gene (5-HTTLPR) and stressful life events (SLEs) to be associated with neural correlates of fear conditioning in a sample of healthy male adults (n = 47). Subjects were exposed to a differential fear conditioning paradigm after being preselected regarding 5-HTTLPR genotype and SLEs. Individual differences in brain activity as measured by functional magnetic resonance imaging (fMRI), skin conductance responses and preference ratings were assessed. We report significant variation in neural correlates of fear conditioning as a function of 5-HTTLPR genotype. Specifically, the conditioned stimulus (CS+) elicited elevated activity within the fear-network (amygdala, insula, thalamus, occipital cortex) in subjects carrying two copies of the 5-HTTLPR S′ allele. Moreover, our results revealed preliminary evidence for a significant gene-by-environment interaction, such as homozygous carriers of the 5-HTTLPR S′ allele with a history of SLEs demonstrated elevated reactivity to the CS+ in the occipital cortex and the insula. Our findings contribute to the current debate on 5-HTTLPR x SLEs interaction by investigating crucial alterations on an intermediate phenotype level which may convey an elevated vulnerability for the development of psychopathology. 相似文献
88.
Martin Grimm Michael Krimmel Dorothea Alexander Adelheid Munz Susanne Kluba Constanze Keutel Juergen Hoffmann Joachim Polligkeit Siegmar Reinert Sebastian Hoefert 《Clinical oral investigations》2013,17(3):949-955
Objectives
Overexpression of the histamine H1 receptor (H1R) has been described in a variety of tumor models, but experience in oral squamous cell carcinomas (OSCC) is not available. Current adjuvant treatment options for OSCC can be improved by the identification of new targets of therapy. Herein, we evaluated H1R expression in a large patient cohort of OSCC.Materials and methods
H1R immunoexpression was evaluated in 191 cases of OSCC and two OSCC cell lines BICR56 and BICR3. Scanned images were digitally analyzed using ImageJ and the immunomembrane plug-in. The combined score of computer-assisted semiquantitative analysis was correlated with manually counted percentages of tumor cells by Kendall’s tau (т) correlation coefficient. Disease-free survival times were estimated using the Kaplan–Meier method and were compared by using the log-rank test. Multivariate analyses were performed using the Cox proportional hazards model.Results
H1R was rarely expressed in OSCC but significantly related with advanced tumor stages (n?=?21/191, mean expression 63.5 % of cancer cells in positive tumor samples, 95 % confidence interval of the mean 53.5 to 73.6 %, p?=?0.006). Following univariate analysis, patients with H1R expression showed a significant poorer prognosis (p?=?0.0004). Multivariate analysis revealed H1R expression as an independent prognostic factor (p?=?0.0164). Expression of H1R in cancer cell lines was confirmed by specific staining of OSCC cell lines BICR56 and BICR3.Conclusion
This is the first study focusing on H1R expression showing a significant poorer DFS rate in the H1R+ patient cohort. Based on these data, H1R activation may promote carcinogenesis in OSCC.Clinical relevance
Investigation of H1R regulation and its antagonists shows a clear rationale for future supportive anticancer therapies in OSCCs. 相似文献89.
Monika Milian Juergen Honegger Christine Gerlach Tsambika Psaras 《Acta neurochirurgica》2013,155(9):1637-1645
Background
Reduced health-related quality of life (HRQoL) is a common complaint in patients suffering from pituitary tumors. Although successful tumor treatment has been reported to lead to an improvement in perceived HRQoL, the temporal gradient at which these improvements occur has not been fully addressed.Methods
Using three validated health-related questionnaires (SF-36, SCL-90-R, QLS-H), we assessed HRQoL in 106 adult patients harboring pituitary tumors (mean age 48.0?±?16.0 years) before as well as 3 and 12 months after initiation of treatment. The AcroQoL questionnaire was additionally applied in acromegalic patients.Results
There was a significant improvement in all but one scale (role-physical) of the SF-36 questionnaire and all but two scales (interpersonal sensitivity, paranoid ideation) of the SCL-90-R, the QLS-H score and the AcroQoL subscales within 3 months after surgical treatment. The trend to amelioration continued at the 12 month re-assessment, but did not reach statistical significance. Linear regression analyses revealed that younger age and male gender favor a more distinct improvement of HRQoL after treatment.Conclusions
HRQoL is considerably reduced before treatment for pituitary disease. Improvement is an early postoperative phenomenon and occurs within 3 months after treatment. Men and younger patients are more likely to improve within this time span. 相似文献90.
Oliver Klass Uwe M. Fischer Albert Antonyan Mafalda Bosse Juergen H. Fischer Wilhelm Bloch 《Journal of investigative surgery》2013,26(6):349-356
Cardiopulmonary bypass (CPB) and cardioplegic arrest are associated with pulmonary dysfunction. We sought to investigate whether pulmonary ischemia/reperfusion during standard CPB and cardioplegic arrest is associated with reactive oxygen species (ROS)-mediated pulmonary tissue injury and pneumocyte apoptosis induction, and whether ROS scavenging using N-acetylcysteine (NAC) attenuates these alterations. Twelve pigs (41 ± 8 kg) were randomized to receive either NAC (100 mg/kg prior to CPB; n = 7) or placebo (n = 5) and subjected to CPB and 60 min of cold (4°C) crystalloid cardioplegic arrest. We collected lung biopsies prior to CPB, at 60 min CPB, as well as at 30, 60, and 120 min post CPB. Lung specimens were immunocytochemically stained against nitrotyrosine, 8-isoprostaglandin-F2α, and 8-hydroxy-2′-deoxyguanosine (8-OH-dG) as indicators for ROS-mediated tissue injury and active caspase-3, an apoptosis signal pathway key enzyme. Oxidative stress markers were judged using a scale from 1 to 4 (low to intensive staining), and caspase-3-positive pneumocytes were counted per view field. In placebo, the number of caspase-3-positive pneumocytes significantly increased over time to reach a maximum at 120 min post CPB (p =. 03 vs baseline). NAC significantly prevented caspase-3 activation in pneumocytes (p =. 001 vs Placebo). Pneumocyte nitrotyrosine and 8-OH-dG staining significantly increased over time (p =. 003) in the placebo group, but decreased in the NAC group (p =. 004). In both groups staining for 8-isoprostaglandin-F2α showed no significant changes. This yields the conclusion that standard CPB and cardioplegic arrest initiate ROS-mediated tissue injury and apoptosis in pneumocytes that can be reduced by NAC. Thus, ROS scavenging using NAC may represent a novel approach to minimize lung injury associated with CPB. 相似文献