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991.
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J Oral Pathol Med (2012) 41 : 372–378 Objectives: A precancerous condition is a lesion that, if left untreated, leads to cancer or can be induced to become malignant. In the oral region, leukoplakia is a lesion that has been regarded as precancerous. In cases of oral carcinoma, we have frequently noticed that a type of leukoplakia histologically demonstrating hyper‐orthokeratosis and mild atypia (ortho‐keratotic dysplasia; OKD) is often associated with carcinoma, either synchronously or metachronously. Therefore, we consider OKD‐type leukoplakia to be a true precancerous lesion. Materials and Methods: In an attempt to clarify the relationship between OKD as a precancerous condition in the oral mucosa and telomere length, we estimated telomere lengths in this type of leukoplakia using quantitative fluorescence in situ hybridization, and also quantified the frequency of anaphase–telophase bridges (ATBs) in comparison with squamous cell carcinoma in situ (CIS) and the background tissues of CIS and OKD. Results: Ortho‐keratotic dysplasia was frequently associated with squamous cell carcinoma (45.0%) and showed significantly shorter telomeres than normal control epithelium, CIS, or the background of CIS or OKD. The frequency of ATBs was much higher in OKD than in control epithelium or CIS. Conclusion: Ortho‐keratotic dysplasia appears to be frequently associated with carcinoma, chromosomal instability, and excessively shortened telomeres, not only in the lesion itself but also in the surrounding background. Therefore, when this type of leukoplakia is recognized in the oral region, strict follow‐up for oral squamous cell carcinoma is necessary, focusing not only on the areas of leukoplakia, but also the surrounding background.  相似文献   
993.
采用免疫组化ABC法检测源自10例颈淋巴清扫患者的正常下颌下腺组织AQP3、7、9蛋白的表达。AQP3在浆液性腺泡和黏液性腺泡细胞均有表达,分布于腺泡细胞的基底膜和侧膜,在浆液性腺泡细胞中的表达明显高于黏液性腺泡细胞,导管系统未见AQP3表达;AQP7在极少数肌上皮细胞有表达;AQP9在部分浆液性腺泡腔、混合性腺泡腔以及部分闰管管腔和浆液性半月体上有表达。  相似文献   
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Concrescence is a rare developmental anomaly with an overall incidence of 0.8% in the permanent dentition. While many case reports describe the treatment of concrescence with extraction, there are few reports of non-surgical root canal treatment (NSRCT), due to the atypical root form, canal morphology, and technical difficulties involved in concrescence. This unique case report describes a technical modification of NSRCT that can retain joined posterior maxillary teeth to maintain natural posterior occlusion without surgical intervention or dental implants, thereby avoiding the risk of damage to a large portion of the alveolar bone near the maxillary sinus.  相似文献   
996.
BackgroundThe diagnostic assessment of the level of difficulty in treating patients who need prosthodontic care is useful to establish a medico-economically efficient system with primary care dentists and prosthodontic specialists.Materials and methodsA multi-axis assessment protocol was established using the newly established treatment difficulty indices. The protocol contains Axis I: oral physiological conditions (e.g., teeth damage and/or missing teeth); Axis II: general health and sociological conditions (e.g., medical disorders); Axis III: oral health-related quality of life (OHRQOL; e.g., oral health impact profile: OHIP); and Axis IV: psychological health (e.g., mood, anxiety, somatoform disorders). A preliminary study on the test–retest consistency of the protocol was conducted to check the levels of reliability of the indices prior to a large-scale, multi-center cohort study on the validity of the protocol.ResultsThe test–retest consistency in terms of the oral physiological condition (Axis I) after data reduction was 0.63 for patients with teeth problems, 0.95 for partially edentulous patients, and 0.62 for edentulous patients. The reliability for general health and sociological conditions (Axis II), OHRQOL (Axis III), and psychological health (Axis IV) were 0.88, 0.74, and 0.61, respectively. These values reflect either “sufficient agreement” or “excellent agreement” in accordance with the criteria established by Landis and Koch (1977) [1].ConclusionThis protocol is the first multi-axis assessment scheme introduced for prosthodontic treatment with sufficient reliability. This new system is therefore expected to have a significant impact on future dental diagnostic nomenclature systems.  相似文献   
997.
Primary anaplastic large cell lymphoma (ALCL) of skeletal muscle is very rare. We report a case of ALCL arising from the left psoas muscle. A 14-year-old girl presented with a large left inguinal tumor. She complained of a 2-month history of left leg pain, which had been exacerbated upon leg extension, and she had become aware of a rapidly growing left inguinal tumor 3 weeks before admission. CT scan and MRI revealed a large tumor arising from the left major psoas muscle and protruding into the inguinal region. In view of the tumor's location and the patient's age, soft tissue tumors such as rhabdomyosarcoma and primitive neuroectodermal tumor were initially considered. However, histopathological examination yielded a diagnosis of anaplastic lymphoma kinase-positive ALCL. The serum level of soluble interleukin-2 receptor was markedly elevated at 50,414 U/ml, and this also strongly suggested ALCL. Although rarely reported, ALCL is an important entity to consider in the differential diagnosis of skeletal muscle tumors in children and young adults.  相似文献   
998.
Mixed-lineage leukemia (MLL)/AF4-positive acute lymphoblastic leukemia (ALL) is a common type of leukemia in infants, which is associated with a high relapse rate and poor prognosis. IL24 selectively induces apoptosis in cancer cells and exerts immunomodulatory and antiangiogenic effects. We examined the effects of adeno-associated virus type 8 (AAV8) vector-mediated muscle-directed systemic gene therapy in MLL/AF4-positive ALL using IL24. In a series of in vitro studies, we examined the effects of AAV8-IL24-transduced C2C12 cell-conditioned medium. We also examined the effects of AAV8-IL24 in MLL/AF4 transgenic mice. The results revealed the effects of AAV8-IL24 in MLL/AF4-positive ALL both in vitro and in vivo. With regard to the mechanism of therapy using AAV8-IL24 in MLL/AF4-positive ALL, we demonstrated the antiangiogenicity and effects on the ER stress pathway and unreported pathways through inhibition of S100A6 and HOXA9, which is specific to MLL/AF4-positive ALL. Inhibition of S100A6 by IL24 was dependent on TNF-α and induced acetylation of p53 followed by activation of the caspase 8-caspase 3 apoptotic pathway. Inhibition of HOXA9 by IL24, which was independent of TNF-α, induced MEIS1 activation followed by activation of the caspase 8-caspase 3 apoptotic pathway. Thus, gene therapy using AAV8-IL24 is a promising treatment for MLL/AF4-positive ALL.  相似文献   
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