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Degradation of the hybrid layer created in dentin by dentin adhesives is caused by enzyme activities present within the dentin matrix that destroy unprotected collagen fibrils. The aim of the present study was to evaluate the effect of a one‐step self‐etch adhesive system on dentinal matrix metalloproteinases 2 and 4 (MMP‐2 and MMP‐9, respectively) using in situ zymography and an enzymatic activity assay. The null hypothesis tested was that there are no differences in the activities of dentinal MMPs before and after treatment with a one‐step adhesive system. The MMP‐2 and MMP‐9 activities in dentin treated with the one‐step adhesive, Adper Easy Bond, were quantified using an enzymatic activity assay system. The MMP activities within the hybrid layer created by the one‐step adhesive tested were also evaluated using in situ zymography. The enzymatic assay revealed an increase in MMP‐2 and MMP‐9 activities after treatment with adhesive. In situ zymography indicated that gelatinolytic activity is present within the hybrid layer created with the one‐step self‐etch adhesive. The host‐derived gelatinases were localized within the hybrid layer and remained active after the bonding procedure. It is concluded that the one‐step self‐etch adhesive investigated activates endogenous MMP‐2 and MMP‐9 with the dentin matrix, which may cause collagen degradation over time.  相似文献   
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This publication describes the history of minimal intervention dentistry (MID) for managing dental caries and presents evidence for various carious lesion detection devices, for preventive measures, for restorative and non‐restorative therapies as well as for repairing rather than replacing defective restorations. It is a follow‐up to the FDI World Dental Federation publication on MID, of 2000. The dental profession currently is faced with an enormous task of how to manage the high burden of consequences of the caries process amongst the world population. If it is to manage carious lesion development and its progression, it should move away from the ‘surgical’ care approach and fully embrace the MID approach. The chance for MID to be successful is thought to be increased tremendously if dental caries is not considered an infectious but instead a behavioural disease with a bacterial component. Controlling the two main carious lesion development related behaviours, i.e. intake and frequency of fermentable sugars, to not more than five times daily and removing/disturbing dental plaque from all tooth surfaces using an effective fluoridated toothpaste twice daily, are the ingredients for reducing the burden of dental caries in many communities in the world. FDI's policy of reducing the need for restorative therapy by placing an even greater emphasis on caries prevention than is currently done, is therefore, worth pursuing.  相似文献   
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Lipofilling is a well-established technique in reconstructive plastic surgery. It is used primarily in recontouring of the body and face to correct post-traumatic and congenital defects. The regenerative properties of adipose tissue have allowed the use of the lipofilling technique for the treatment of burn sequelae and irradiated breast to improve tissue quality and elasticity. We report on the case of a patient treated with radiation therapy for a nasopharyngeal carcinoma who presented with severe postradiation dysphagia. The lipofilling technique was successfully used to improve abnormal swallowing. The technical details and functional outcomes are discussed.  相似文献   
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BackgroundIn the phase III MDS-005 study of patients with lower-risk, non-del(5q) myelodysplastic syndromes, lenalidomide was associated with a higher rate of ≥ 8 weeks red blood cell transfusion independence (RBC-TI) compared with placebo, but also with a higher risk of hematologic adverse events (AEs).Patients and MethodsThis analysis evaluated the ratio of clinical benefit-risk in patients treated with lenalidomide or placebo, and assessed the effect of lenalidomide dose reductions on response. Clinical benefit was a composite endpoint defined as RBC-TI, transfusion reduction ≥ 4 units packed red blood cells, hemoglobin increase ≥ 1.5 g/dL, or cytogenetic response.ResultsThe rate of clinical benefit was higher with lenalidomide than with placebo (31.9% vs. 3.8%). The ratio of response (RBC-TI and clinical benefit) to risk (hematologic AEs) favored lenalidomide over placebo. Patients who underwent ≥ 1 lenalidomide dose reduction had a longer duration of treatment, received a higher cumulative dose, and were more likely to experience clinical benefit versus patients without dose reductions.ConclusionDespite the occurrence of hematologic AEs, the overall benefit-risk profile supported lenalidomide treatment. Appropriate management of hematologic AEs by dose reductions may help patients with myelodysplastic syndromes to remain on treatment and achieve clinical benefit.  相似文献   
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Helicobacter pylori(H.pylori)has been found in the oral cavity and stomach,and its infection is one of the most frequent worldwide.We reviewed the literature and conducted a Topic Highlight,which identified studies reporting an association between H.pylori-infection in the oral cavity and H.pylori-positive stomach bacterium.This work was designed to determine whether H.pylori is the etiologic agent in periodontal disease,recurrent aphthous stomatitis(RAS),squamous cell carcinoma,burning and halitosis.Record selection focused on the highest quality studies and meta-analyses.We selected 48 articles reporting on the association between saliva and plaque and H.pylori-infection.In order to assess periodontal disease data,we included 12 clinical trials and 1 meta-analysis.We evaluated 13 published articles that addressed the potential association with RAS,and 6 with squamous cell carcinoma.Fourteen publications focused on our questions on burning and halitosis.There is a close relation between H.pylori infection in the oral cavity and the stomach.The mouth is the first extra-gastric reservoir.Regarding the role of H.pylori in the etiology of squamous cell carcinoma,no evidence is still available.  相似文献   
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IntroductionSilicosis is a chronic progressive disease caused by inhalation of crystalline silica. Most cases develop in underground mine workers and in subjects involved in the extraction of natural stone (slate and granite). In view of the progressive emergence of new cases of silicosis in artificial quartz conglomerate workers, we performed a study to analyze the characteristics of silicosis produced by this new agent in Spain.MethodsThe study consisted of a series of 96 cases of silicosis diagnosed according to international criteria during the period 2010-2017. We analyzed clinical, radiological, pathological and functional characteristics.ResultsMean age of participants was 45 years; 55% had simple silicosis and 45% had complicated silicosis. Ten patients were diagnosed with accelerated silicosis, with a mean age of 33 years. Mean time of exposure to conglomerates was 15 years, and 77% had not used appropriate protection measures. Half of the patients were asymptomatic and presented different classic forms on chest X-ray and chest high-resolution computed tomography, along with ground-glass images. No lung function changes were recorded.ConclusionsSilicosis in artificial quartz conglomerate workers occurs in a young, actively employed population, a considerable percentage of whom present an accelerated form. They have few symptoms and no functional limitations. Protection measures are scarce. It is important to characterize these features to provide early diagnosis and implement the necessary preventive measures.  相似文献   
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