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991.
992.
Clinical Oral Investigations - The objective of the study was to assess the impact of periodontal crown lengthening surgery on clinical parameters at adjacent and non-adjacent sites compared to...  相似文献   
993.

Background

Historically, the complete removable denture is the last prosthetic procedure to switch to digital techniques whose advantages are mainly observed in the laboratory stages; however, it is not possible to measure the depressibility of the oral mucosa using optical cameras, thus conventional impression techniques are still necessary. This article describes the clinical and laboratory procedure and practitioners appraisal of the first fifteen digitally designed complete removable dental prostheses.

Methods

Several systems are now available including the Wieland® Digital Denture® which offers a complete procedure. This system is composed of a five axis-milling machine combined with a laboratory scanner and a design software application. Fifteen rehabilitations were carried out using the Wieland® system.

Results

The practitioner’s role is simplified by intraoral recording with a central point and a reduced number of sessions. The prosthesis laboratory requires considerable investment in learning and equipment, making it possible to obtain ideal mounting assemblies in accordance with the occluso-prosthetic concept of bilateral balanced occlusion. The absence of polymerization and therefore of base deformation risks reduce the equilibration step. Finally, the creation of templates as an alternative to the assembly of teeth on wax makes it possible to functionally validate (masticatory and phonatory) the future dentures. However, this procedure still presented some limitations in terms of scanning and software scope of applications.

Conclusion

Digital denture design software is relatively efficient and helps to standardize clinical results. However, to this date, improvements of the software are still required for a routine use.
  相似文献   
994.
In this study, we describe the phenotypic spectrum of distal hereditary motor neuropathy caused by mutations in the small heat shock proteins HSPB1 and HSPB8 and investigate the functional consequences of newly discovered variants. Among 510 unrelated patients with distal motor neuropathy, we identified mutations in HSPB1 (28 index patients/510; 5.5%) and HSPB8 (four index patients/510; 0.8%) genes. Patients have slowly progressive distal (100%) and proximal (13%) weakness in lower limbs (100%), mild lower limbs sensory involvement (31%), foot deformities (73%), progressive distal upper limb weakness (29%), mildly raised serum creatine kinase levels (100%), and central nervous system involvement (9%). We identified 12 HSPB1 and four HSPB8 mutations, including five and three not previously reported. Transmission was either dominant (78%), recessive (3%), or de novo (19%). Three missense mutations in HSPB1 (Pro7Ser, Gly53Asp, and Gln128Arg) cause hyperphosphorylation of neurofilaments, whereas the C‐terminal mutant Ser187Leu triggers protein aggregation. Two frameshift mutations (Leu58fs and Ala61fs) create a premature stop codon leading to proteasomal degradation. Two mutations in HSPB8 (Lys141Met/Asn) exhibited increased binding to Bag3. We demonstrate that HSPB1 and HSPB8 mutations are a major cause of inherited motor axonal neuropathy. Mutations lead to diverse functional outcomes further demonstrating the pleotropic character of small heat shock proteins.  相似文献   
995.
996.

Background

Cogan syndrome is mainly treated with steroids. We aimed to determine the place of DMARDs and biologic-targeted treatments.

Patients and methods

We conducted a French nationwide retrospective study of patients with Cogan syndrome (n = 40) and a literature review of cases (n = 22) and analyzed the efficacy of disease-modifying anti-rheumatic drugs (DMARDs) and tumor necrosis factor α (TNF-α) antagonists.

Results

We included 62 patients (31 females) (median age 37 years [range 2–76]. At diagnosis, 61 patients (98%) had vestibulo-auditory symptoms, particularly bilateral hearing loss in 41% and deafness in 31%. Ocular signs were present in 57 patients (92%), with interstitial keratitis in 31 (51%). The first-line treatment consisted of steroids alone (n = 43; 70%) or associated with other immunosuppressive drugs (n = 18; 30%). Overall, 13/43 (30%) and 4/18 (22%) patients with steroids alone and with associated immunosuppressive drugs, respectively (p = 0.8), showed vestibulo-auditory response; 32/39 (82%) and 15/19 (79%) ocular response; and 23/28 (82%) and 10/14 (71%) general response. Overall 61 patients had used a total of 126 lines of treatment, consisting of steroids alone (n = 51 lines), steroids with DMARDs (n = 65) and infliximab (n = 10). Vestibulo-auditory response was significantly more frequent with infliximab than DMARDs or steroids alone (80% vs 39% and 35%, respectively), whereas ocular, systemic and acute-phase reactant response rates were similar. Infliximab was the only significant predictor of vestibulo-auditory improvement (odds ratio 20.7 [95% confidence interval 1.65; 260], p = 0.019).

Conclusion

Infliximab could lead to vestibulo-auditory response in DMARDS and steroid-refractory Cogan syndrome, but prospective studies are necessary.  相似文献   
997.
998.
BACKGROUND: An attenuated immunodeficiency virus has been long considered innocuous. Nevertheless, converging data suggest that low levels of viral replication can still provoke AIDS. Pathogenesis of these attenuated infections is not understood. OBJECTIVES: To determine the pathogenicity of a long-term attenuated infection and to delineate T-cell dynamics during such an infection. METHODS: This is a cross-sectional study of 12 rhesus macaques infected with SIV Delta nef for 8 years. We evaluated apoptosis (annexin V), activation (HLA-DR, Ki67), and newly generated T cells (TCR excision circle: TREC). RESULTS: Infection with SIV Delta nef induced pathological CD4 T-cell depletion after 8 years of infection. Virus replication and CD8 T-cell activation positively correlated with the rate of disease progression. The frequency of TREC within CD8+CD45RA+ cells increased in SIV Delta nef-infected animals compared to age-matched non-infected controls. Moreover, in the cohort of infected animals, TREC+CD45RA+CD4+ T-cell counts correlated strongly with non-progression to AIDS. The animal with the lowest rate of disease progression exhibited a 115-fold increase in TREC+CD45RA+CD4+ T-cell counts compared to age-matched non-infected controls. In contrast, the animal showing the fastest rate of progression to AIDS displayed 600-fold lower TREC+CD45RA+CD4+ T-cell counts compared to age-matched non-infected controls. CONCLUSIONS: Our results suggest that the thymus plays a major role in the pathogenesis of an attenuated SIV infection and that a sustained thymic output could maintain CD4 T-cell homeostasis in the context of low viral loads.  相似文献   
999.
1000.
Haemostatis has not previously been studied in patients with neurofibromatosis 1 (NF-1), despite case reports of an association with von Willebrand disease and reported excessive bleeding in those undergoing surgery for neurofibromas. Platelets from NF-1 patients ( n = 28) were tested for aggregation and ATP release with agonists including ADP, arachidonic acid, thrombin and collagen. Mepacrine staining of platelets and three different assays for von Willebrand factor (VWF) were also performed.
In response to collagen as the platelet agonist, tested at both 2 and 1 μg/ml, NF-1 patients had an attenuated rate of aggregation ( P < 0.007), aggregation lag phase ( P < 0.005) and ATP release ( P < 0.045), as well as requiring higher collagen concentrations to attain threshold aggregation response ( P = 0.041). Normal platelets resuspended in selected NF-1 plasma exhibited significantly reduced platelet aggregation and release compared to controls, which was not corrected by mixing 1:1 with normal plasma. Collagen binding activity was reduced in NF-1 patients compared with controls (127% v 161%, P = 0.05).
As a group, patients with NF-1 display defective platelet function characterized by in vitro evidence of impaired responsiveness to collagen. It is suggested that a plasma factor, present in a significant proportion of NF-1 patients, may interfere with the ability of collagen to interact with other proteins such as von Willebrand factor and the platelet collagen receptor.  相似文献   
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