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A newborn with severe microcephaly and a history of parental consanguinity was referred for cytogenetic analysis and subsequently for genetic evaluation. While a 46,XY karyotype was eventually obtained, premature chromosome condensation was observed. A head MRI confirmed primary microcephaly. This combination of features focused clinical interest on the MCPH1 gene and directed genetic testing by sequence analysis and duplication/deletion studies disclosed a homozygous deletion of exons 1–11 of the MCPH1 gene. This case illustrates a strength of standard cytogenetic evaluation in directing molecular testing to a single target gene in this disorder, allowing much more rapid diagnosis at a substantial cost savings for this family.  相似文献   
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The vast majority of Alzheimer's disease (AD) are late-onset forms (LOAD) likely due to the interplay of environmental influences and individual genetic susceptibility. Epigenetic mechanisms, including DNA methylation, histone modifications and non-coding RNAs, constitute dynamic intracellular processes for translating environmental stimuli into modifications in gene expression. Over the past decade it has become increasingly clear that epigenetic mechanisms play a pivotal role in aging the pathogenesis of AD. Here, we provide a review of the major mechanisms for epigenetic modification and how they are reportedly altered in aging and AD. Moreover, we also consider how aberrant epigenetic modifications may lead to AD pathogenesis, and we review the therapeutic potential of epigenetic treatments for AD.  相似文献   
997.
Background: In China, chronic periodontitis (CP) is common in patients with type 2 diabetes mellitus (T2DM). The purpose of this study is to identify the sociodemographic characteristics associated with such patients and to assess the periodontal health status and subgingival microbiota of patients with CP and T2DM (T2DMCP) in the Chinese population. Methods: A total of 150 patients with T2DMCP and 306 patients with CP without any systemic disease completed questionnaires, underwent clinical periodontal examinations and participated in diabetes‐related parameter examinations. Subgingival plaques were obtained to determine the prevalence and amounts of selected oral bacterial species using polymerase chain reaction (PCR) and real‐time PCR, respectively. Results: The income level and mean body mass index (BMI) of the patients with T2DMCP were significantly higher than those of the patients with CP. Additionally, the patients with T2DMCP were more likely to be urban residents, and they had significantly more severe periodontitis than did the patients with CP. In the patients with T2DMCP, the prevalence and amounts of Treponema denticola and Tannerella forsythia were significantly higher than those in the patients with CP. Finally, compared with the patients with CP, the patients with T2DMCP had a significantly lower prevalence and amount of Prevotella intermedia. Conclusions: Compared with the patients with CP, the patients with T2DMCP were more likely to be urban residents and generally had higher incomes, higher mean BMI, and poorer periodontal health status. Higher levels of T. denticola and T. forsythia and lower levels of P. intermedia were identified in the subgingival plaque of the patients with T2DMCP.  相似文献   
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Reconstruction of defects of the lip caused by cancer with its requirements of a complicated anatomical structure, important physiological function, and acceptable cosmetic result, is a challenge for oral and maxillofacial and plastic surgeons. A method that combines rotation and advancement flaps was described by Yu in 1989 for the reconstruction of defects of the lower lip. In our department between January 1992 and December 2012, 8 patients had reverse Yu flaps for the reconstruction of upper lip defects and 56 patients had classic Yu flaps for lower lip defects. Patients with defects located laterally to the upper lips, ranging from ? to ½, had unilateral reverse Yu flaps, and bilateral procedures were done for defects of less than ? of the lips. However, if the defects were located in the centre of the upper lips, between ? and ½, they were treated with bilateral reverse Yu flaps. Patients with defects between? and ? of lower lips had unilateral Yu flaps, and if the defects were wider than ? of the lower lips, the procedure was bilateral. No flap failed and desirable functional and aesthetic outcomes were recorded in all cases. Here we report our experience with the Yu flap for the benefit of other surgeons.  相似文献   
1000.

Background

The aim of this study was to examine the quality and quantity of feedback and instruction from faculty members during an acute trauma surgery team training using a newly designed observational feedback instrument.

Methods

During the training, 11 operating teams, each consisting of 1 instructor coaching 2 trainees, were videotaped and audiotaped. Forty-five minutes of identical operating scenarios were reviewed and analyzed. Using a new observational feedback instrument, feedback and instruction, containing different levels of specific information related to technical and nontechnical skills, were noted.

Results

Instructors more often provided instruction (25.8 ± 10.6 times) than feedback (4.4 ± 3.5 times). Most feedback and instruction contained either nonspecific or less specific information and referred to technical skills. Instructors addressed communication skills more specifically.

Conclusions

Coaching by faculty members predominantly contained unspecific instructions regarding technical skills. The observational feedback instrument enabled scoring of the coaching activities.  相似文献   
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