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Akiko Hiraiwa Kou Matsui Yumi Nakayama Takao Komatsubara Shinichi Magara Yu Kobayashi Moemi Hojo Mitsuhiro Kato Toshiyuki Yamamoto Jun Tohyama 《Brain & development》2021,43(3):448-453
BackgroundPallister-Killian syndrome (PKS) is a rare disorder caused by the mosaic tetrasomy of chromosome 12p, and is characterized by facial dysmorphism, developmental delay, hypotonia and seizures.ResultsWe report a patient with PKS showing unique polymicrogyria with calcification. He had delayed development and dysmorphic facial features including frontal bossing, hypertelorism, and high arched palate at 6 months of age. Neuroimaging revealed unilateral polymicrogyria with spot calcifications, which predominantly affected the right perisylvian region. Chromosome G-banding showed the karyotype 46,XY, however, array-based comparative genomic hybridization analysis showed mosaic duplication of chromosome 12p, in which CCND2, which encodes cyclin D2 and is a downstream mediator of PI3K-AKT pathway, is located. Supernumerary chromosome of 12p was detected in 58% of buccal mucosa cells by the interphase fluorescence in situ hybridization analysis using chromosome 12 centromere-specific D12Z3 probe. The diagnosis of PKS was made based on distinctive clinical features of our patient and the results of cytogenetic analyses.ConclusionThis report is, to our knowledge, the first case of a patient with PKS who clearly demonstrates polymicrogyria colocalized with calcifications, as shown by CT scans and MRI, and suggests that a patient with PKS could show structural brain anomalies with calcification. We assume that somatic mosaicism of tetrasomy could cause asymmetrical polymicrogyria in our patient, and speculate that increased dosages of CCND2 at chromosome 12p might be involved in the abnormal neuronal migration in PKS. 相似文献
43.
S. Wang H. Li Z. Kou F. Ren Y. Jin L. Yang X. Dong M. Yang J. Zhao H. Liu N. Dong L. Jia X. Chen Y. Zhou S. Qiu R. Hao H. Song 《Clinical microbiology and infection》2021,27(3):443-450
ObjectivesUndetectable or low-level hepatitis B virus (HBV) DNA and drug resistance mutations in patients may increase the risk of HBV transmission or cause active viral replication and other clinical problems. Here, we established a highly sensitive and practical method for HBV and drug resistance detection using a polymerase chain reaction (PCR) -based CRISPR-Cas13a detection system (referred to as PCR-CRISPR) and evaluated its detection capability using clinical samples.MethodsSpecific CRISPR RNAs (crRNAs) are designed for HBV DNA detection and YMDD (tyrosine-methionine-aspartate-aspartate) variant identification. The HBV DNA was detected in 312 serum samples for HBV diagnosis using quantification PCR (qPCR) and PCR-CRISPR. Additionally, 424 serum samples for YMDD testing were detected by qPCR, direct sequencing, and our assay.ResultsUsing PCR-CRISPR, one copy per test of HBV DNA was detected with HBV-1 crRNA in 15 min after PCR amplification. Consistent results with qPCR were observed for 302 samples, while the remaining 10 samples with low-level HBV DNA were detectable by PCR-CRISPR and droplet digital PCR but not by qPCR. PCR-CRISPR diagnosed all 412 drug-resistant samples detected by the YMDD detection qPCR kit and direct sequencing, as well as the other 12 drug-resistant samples with low-level HBV DNA undetectable by qPCR and direct sequencing.ConclusionsWe developed a novel PCR-CRISPR method for highly sensitive and specific detection of HBV DNA and drug resistance mutations. One copy per test for HBV DNA and YMDD drug resistance mutations could be detected. This method has wide application prospects for the early detection of HBV infection, drug resistance monitoring and treatment guidance. 相似文献
44.
目的 探讨无托槽隐形矫治器设计平面导板,对上中切牙压低效率的影响及支抗前磨牙、磨牙的变化,以期对无托槽隐形矫治器设计平面导板矫治深覆(牙合)提供参考.方法 分别选取无托槽隐形矫治器设计平面导板和无平面导板矫治深覆(牙合)的病例各6例,两组均设计上中切牙不少于0.7mm的压低,通过前牙压低矫正深覆(牙合).前磨牙及磨牙作为支抗牙不设计移动.以腭穹窿为参照,重叠设计压低前后的数字化模型,比较两组上颌中切牙压低效率的差异,以及两组支抗前磨牙和磨牙的差异.结果 平面导板组上中切牙压低效率为33%,无平面导板组上中切牙压低效率为8%,二者的差异无统计学意义(P>0.05);平面导板组第一前磨牙、第二前磨牙、第一磨牙和第二磨牙分别伸长0.3、0.1、0.2和0.1mm;无平面导板组第一前磨牙、第二前磨牙、第一磨牙和第二磨牙分别压低0.0、0.2、0.1和0.1mm,两组的差异均有统计学意义(P<0.05);平面导板组和无平面导板组未设计移动的第一磨牙分别颊倾0.0mm和0.3mm,二者的差异有统计学意义(P<0.05).结论 无托槽隐形矫治器设计平面导板对上颌中切牙的压低无明显影响,但能有效伸长支抗前磨牙及磨牙,克服无托槽隐形矫治器"(牙合)垫效应"造成的后牙压低,并维持磨牙水平向的位置,对深覆(牙合)的矫正发挥一定作用. 相似文献
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46.
Yu-hui Kou Pei-xun Zhang Yan-hua Wang Bo Chen Na Han Feng Xue Hong-bo Zhang Xiao-feng Yin Bao-guo Jiang 《中国神经再生研究》2015,10(1):53-59
Multiple-bud regeneration, i.e., multiple amplification, has been shown to exist in peripheral nerve regeneration. Multiple buds grow towards the distal nerve stump during proximal nerve fiber regeneration. Our previous studies have verified the limit and validity of multiple amplification of peripheral nerve regeneration using small gap sleeve bridging of small donor nerves to repair large receptor nerves in rodents. The present study sought to observe multiple amplification of myelinated nerve fiber regeneration in the primate peripheral nerve. Rhesus monkey models of distal ulnar nerve defects were established and repaired using muscular branches of the right forearm pronator teres. Proximal muscular branches of the pronator teres were sutured into the distal ulnar nerve using the small gap sleeve bridging method. At 6 months after suture, two-finger flexion and mild wrist flexion were restored in the ulnar-sided injured limbs of rhesus monkey. Neurophysiological examination showed that motor nerve conduction velocity reached 22.63 ± 6.34 m/s on the affected side of rhesus monkey. Osmium tetroxide staining demonstrated that the number of myelinated nerve fibers was 1,657 ± 652 in the branches of pronator teres of donor, and 2,661 ± 843 in the repaired ulnar nerve. The rate of multiple amplification of regenerating myelinated nerve fibers was 1.61. These data showed that when muscular branches of the pronator teres were used to repair ulnar nerve in primates, effective regeneration was observed in regenerating nerve fibers, and functions of the injured ulnar nerve were restored to a certain extent. Moreover, multiple amplification was subsequently detected in ulnar nerve axons. 相似文献
47.
目的:检测胃癌组织中P27的表达及其与cyclin D_1、cyclin E表达的相关性,并探讨其意义.方法:临床病理资料齐全的胃癌蜡块标本54例,正常胃黏膜标本15例,采用SP免疫组化方法检测P27、cyclin D和cyclin E在其中的表达.结果:胃癌组织54例中有20例P27表达阳性(37.0%),正常胃组织中15例有11例P27呈阳性表达(73.3%),胃癌组织与正常胃组织相比,P27的表达有明显差异(P<0.05),胃癌组织中P27的表达与患者的性别、年龄及肿瘤大小,浸润深度,分化程度无相关性(P>0.05),而与TNM分期及有无淋巴结转移明显相关(P<0.05),P27的表达与cyclin D_1的表达呈负相关(r=-0.332),而与cyclin E的表达无明显相关性(p>0.05).结论:胃癌组织中P27表达与正常胃组织有显著差异,胃癌组织中P27蛋白表达与淋巴结转移及临床分期密切相关,与cyclin E的表达呈负相关. 相似文献
48.
脑外伤(traumatic brain injury,TBI)伴发精神障碍损伤机制正逐渐成为认知神经科学研究的焦点。目前对脑外伤后精神障碍的诊断主要依赖临床评估,具体发病机制知之甚少。最近基于影像学的研究发现脑外伤导致的病理改变并非传统观念认为的一过性损伤,其对脑网络功能及属性的破坏可能是终身的,这在一定程度上增加了阿尔茨海默病,创伤性脑病等远期后遗症的患病风险。作者拟对脑外伤出现精神障碍患者影像学改变的研究现状进行综述。 相似文献
49.
Evaluation of a Standardized Program for Training Practicing Anesthesiologists in Ultrasound‐Guided Regional Anesthesia Skills
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50.
Hong-Shi Li Jie Ke Gui-Zhi Zhao Li-An Wu Jun-Ping Kou Hong-Chen Liu 《中华医学杂志(英文版)》2015,128(14):1948-1955
Background:The pain caused by orthodontic treatment has been considered as tough problems in orthodontic practice.There is substantial literature on pain which has exactly effected on learning and memo... 相似文献