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Oral squamous cell carcinomas (OSCCs) develop in genetically altered epithelium in the mucosal lining, also coined as fields, which are mostly not visible but occasionally present as white oral leukoplakia (OL) lesions. We developed a noninvasive genetic assay using next-generation sequencing (NGS) on brushed cells to detect the presence of genetically altered fields, including those that are not macroscopically visible. The assay demonstrated high accuracy in OL patients when brush samples were compared with biopsies as gold standard. In a cohort of Fanconi anemia patients, detection of mutations in prospectively collected oral brushes predicted oral cancer also when visible abnormalities were absent. We further provide insight in the molecular landscape of OL with frequent changes of TP53, FAT1 and NOTCH1. NGS analysis of noninvasively collected samples offers a highly accurate method to detect genetically altered fields in the oral cavity, and predicts development of OSCC in high-risk individuals. Noninvasive genetic screening can be employed to screen high-risk populations for cancer and precancer, map the extension of OL lesions beyond what is visible, map the oral cavity for precancerous changes even when visible abnormalities are absent, test accuracy of promising imaging modalities, monitor interventions and determine genetic progression as well as the natural history of the disease in the human patient.  相似文献   
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地鳖中的纤溶活性蛋白是从地鳖中提取的具有抗栓及抗肿瘤作用的有效成分,其口服易被上消化道酶分解从而限制了应用。采用恒流泵滴制法开发地鳖纤溶活性蛋白时间/pH依赖口服结肠靶向微囊(EnpolypHaga fibrinolytic protein oral colon targeting microcapsules, CTM-EFP)。采用单因素实验和正交实验相结合的方法寻找到包封率为60.17 % ± 2.72 %、载药量为15.50 % ± 0.44 % 的最佳配方。扫描电子显微镜(SEM)显示微囊呈球形、表面光滑,在人工肠液中24 h的累积释放度为99.53 % ± 0.69 %,在人工胃液中24 h累积释放度为7.43 ± 1.04 %,通过时间/pH依赖达到结肠靶向作用。CTM-EFP在人工肠液中的体外释放曲线符合Korsmeyer方程,提示地鳖纤溶活性蛋白(EnpolypHaga fibrinolytic protein, EFP)是通过扩散和侵蚀机制结合释放的。CTM-EFP为EFP的口服给药提供了一种新的剂型,为EFP应用于临床提供参考。  相似文献   
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ObjectivesMap regional lymph node metastases for lateralized oral cavity squamous cell carcinoma (OCSCC) and evaluate factors associated with regional metastases and recurrence.Materials and methodsRetrospective cohort study of 715 patients with lateralized OCSCC surgically treated in 1997–2011. Analysis was performed using log-rank, Kaplan-Meier, and multivariable logistic and Cox regression.ResultsRegional metastases were identified in ipsilateral levels IIA (24%), IB (18%), III (13%), V (9%), IV (7%), IA (2%) and IIB (1%) and the contralateral neck (3%). Lymphovascular invasion (LVI) (Hazard Ratio [HR] 2.2, 95% Confidence Interval [CI] 1.2–3.9) and T category (T3 vs. T1: HR 4.1, 95% CI 1.9–9.3; T4 vs. T1: HR 2.3, 95% CI 1.2–4.3) were associated with regional metastases. Most (71%) isolated regional metastatic recurrences were in undissected levels of the neck, including 58% in levels IV and V. Tumors of the hard palate (HR 4.3, 95% CI 1.2–16.1), upper alveolus (HR 3.2, 95% CI 1.0–4.7) or with LVI (HR 2.0, 95% CI 1.0–3.9) were associated with isolated regional recurrence. For upper alveolar/hard palate tumors, depth of invasion (DOI) ≥4 mm (P = .003) and LVI (P = .04) were associated with regional metastases.ConclusionsFor lateralized OCSCC, elective neck dissection of level IIB or the contralateral neck may rarely be needed, but additional surgical or radiation treatment of levels IV and V may be considered based on patient risk factors, including T category 3–4 or LVI. For upper alveolar/hard palate tumors, DOI ≥4 mm is an appropriate threshold for elective neck dissection.  相似文献   
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IntroductionThis study was designed to assess whether a dental caries management protocol combining a single application of 38% silver diamine fluoride (SDF) with comprehensive oral health education will successfully divert high-risk children from dental treatment under dental general anaesthesia (DGA), arrest active caries in primary teeth, and improve parent-reported child oral health–related quality of life (OHRQoL).MethodsChildren aged 2 to 10 years, who attended two public dental agencies in Victoria, Australia, and were unable to tolerate restorative treatments in the clinic setting, elected to participate in either a 38% SDF intervention protocol or, alternatively, referral for DGA. Follow-up examinations were completed at 6 months to assess caries progression, decayed missing filled tooth index, PUFA index (pulpal involvement, ulceration, fistula, abscess), DGA referral rates, and OHRQoL (Early Childhood Oral Health Impact Scale [ECOHIS]).ResultsOf the total sample, 89.5% of children (n = 102) [mean (SD) age, 4.1 (1.0) years] with 401 active carious lesions elected to participate in the 38% SDF protocol; 10.5% (n = 12) of parents opted for referral for treatment under DGA. The proportion of active caries subsequently arrested at follow-up (number of arrested lesions/number of lesions treated) was 0.78 (95% CI, 0.69 to 0.87). There was an 88% reduction in referrals for DGA in eligible children over the 6-month period. The 38% SDF intervention group showed a significant improvement in ECOHIS scores at follow-up (P < .001).DiscussionAdoption of the 38% SDF intervention protocol resulted in a significant reduction in the rate of preventable dental hospitalisations. Most parents opted against referral for DGA. Parent-reported OHRQoL for children improved significantly.  相似文献   
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Patients undergoing sentinel node biopsy (SLNB) for early oral squamous cell carcinoma (OSCC) who harbour occult metastases (pN+ve) may be at greater risk of mortality due to prolonged overall treatment times than those identified as pN+ve on elective neck dissection (ELND). A retrospective comparative survival analysis was therefore undertaken to test this hypothesis. Patients were identified from the South Glasgow multidisciplinary team (MDT) database. Group 1 comprised 38 patients identified as pN+ve, or who were false negative, on sentinel lymph node biopsy (SLNB). Group 2 comprised 146 patients staged pN+ve on ELND. The groups were compared with the Kaplan Meier method and Cox proportional hazards model. In addition, a matched-pair analysis was performed. A unique and specifically designed algorithm was deployed to optimise the pairings. No difference in disease-specific or overall survival was found between the groups. Patients undergoing SLNB as the initial neck staging modality in early OSCC and are identified as pN+ve do not appear to be at a survival disadvantage compared with those staged with ELND.  相似文献   
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Increasing trend in oral cancer (0.6% per year) and its related mortality has been reported worldwide since 2010. The United States alone reports an increase of 57% within the past 10 years. This emphasizes the need not only for designing strategies of prevention and planning but also for an effective treatment regime for the various oral cancers. Cancers of the lips, tongue, cheeks, floor of the mouth, and hard palate have been primarily classified under the category of oral cancers. If left undiagnosed, these cancers can be life threatening. Amongst these, the most undesignated and understudied cancer type is the lip carcinoma, which is either categorized under oral cancer or/as well as skin cancer or head and neck cancer. However, lip cancer corresponds to 25–30% of all diagnosed oral cancers. Though the etiology of lip cancer is not yet fully understood, numerous risk factors involved in its development are now being studied. The cells in the lip region are continuously exposed to various DNA damaging agents from endogenous as well as exogenous sources. Flaws in DNA repair mechanisms involved in eliminating these damages may be linked to the origin of carcinogenesis. Accumulation of DNA damage and defect in repair mechanisms may play a role in lip carcinogenesis and progression. This literature review is an exhaustive compilation of the research work performed on the role of DNA damage and repair responses in lip carcinoma which will pave a path for researchers to identify predictive DNA repair biomarker/s for lip cancer, and its diagnosis, prevention, and treatment.  相似文献   
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