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81.
Natsuo Yasui Keiichi Ozono Masayo Yamagata Hidehiko Kawabata Hideki Yoshikawa 《American journal of medical genetics. Part A》2001,99(4):328-330
A 23‐year‐old man was diagnosed as having X‐linked spondyloepiphyseal dysplasia tarda (SEDT; MIM 313400) based on his disproportionately short trunk, short stature, characteristic radiological features of the spine (posterior hump, end plate sclerosis, and disc space narrowing) and the hips (short and thick femoral necks), and positive family history. This Japanese family was found to have an intragenic deletion flanking intron 2 and exon 3 of the SEDL gene that not only included the 5′ untranslated region but also the coding sequence for the first methionine through the 25th alanine. This mutation was present in the proband and his unaffected mother (a heterozygote), but not in an unaffected sister and an unaffected uncle. The nature of the mutation predicted that the SEDL protein (Sedlin) was not produced in the proband, indicating that loss of Sedlin caused SEDT. © 2001 Wiley‐Liss, Inc. 相似文献
82.
83.
Hidetoshi Taniguchi Ikuko Mohri Hitomi Okabe-Arahori Takahisa Kanekiyo Kuriko Kagitani-Shimono Kazuko Wada Yoshihiro Urade Masahiro Nakayama Keiichi Ozono Masako Taniike 《Neuroscience letters》2007
Lipocalin-type prostaglandin (PG) D synthase (L-PGDS) is up-regulated in oligodendrocytes (OLs) in mouse models for genetic neurological disorders including globoid cell leukodystrophy (twitcher) and GM1 and GM2 gangliosidoses and in the brain of patients with multiple sclerosis. Since L-PGDS-deficient twitcher mice undergo extensive neuronal death, we concluded that L-PGDS functions protectively against neuronal degeneration. In this study, we investigated whether L-PGDS is also up-regulated in acute and massive brain injury resulting from neonatal hypoxic-ischemic encephalopathy (HIE). Analysis of brains from human neonates who had died from HIE disclosed that the surviving neurons in the infarcted lesions expressed L-PGDS. Mouse models for neonatal HIE were made on postnatal day (PND) 7. Global infarction in the ipsilateral hemisphere was evident at 24 h after reoxygenation in this model. Intense L-PGDS immunoreactivity was already observed at 10 min after reoxygenation in apparently normal neurons in the cortex, and thereafter, in neurons adjacent to the infarcted area. Quantitative RT-PCR revealed that the L-PGDS mRNA level of the infarcted hemisphere was 33-fold higher than that of the sham-operated mouse brains at 1 h after reoxygenation and that it decreased to the normal level by 24 h thereafter. Furthermore, in both human and mouse brains, many of L-PGDS-positive cells were also immunoreactive for p53; and some of these expressed cleaved caspase-3. The expression of L-PGDS in degenerating neurons implies that L-PGDS functions as an early stress protein to protect against neuronal death in the HIE brain. 相似文献
84.
Margaux Serey‐Gaut Marcello Scala Bruno Reversade Lyse Ruaud Christelle Cabrol Francesco Musacchia Annalaura Torella Andrea Accogli Nathalie Escande‐Beillard Jean Langlais Gianluca Piatelli Alessandro Consales Vincenzo Nigro Valeria Capra Lionel Van Maldergem 《American journal of medical genetics. Part A》2020,182(6):1466-1472
The clinical and radiological spectrum of spondylocostal dysostosis syndromes encompasses distinctive costo‐vertebral anomalies. RIPPLY2 biallelic pathogenic variants were described in two distinct cervical spine malformation syndromes: Klippel–Feil syndrome and posterior cervical spine malformation. RIPPLY2 is involved in the determination of rostro‐caudal polarity and somite patterning during development. To date, only four cases have been reported. The current report aims at further delineating the posterior malformation in three new patients. Three patients from two unrelated families underwent clinical and radiological examination through X‐ray, 3D computed tomography and brain magnetic resonance imaging. After informed consent was obtained, family‐based whole exome sequencing (WES) was performed. Complex vertebral segmentation defects in the cervico‐thoracic spine were observed in all patients. WES led to the identification of the homozygous splicing variant c.240‐4T>G in all subjects. This variant is predicted to result in aberrant splicing of Exon 4. The current report highlights a subtype of cervical spine malformation with major atlo‐axoidal malformation compromising spinal cord integrity. This distinctive mutation‐specific pattern of malformation differs from Klippel–Feil syndrome and broadens the current classification, defining a sub‐type of RIPPLY2‐related skeletal disorder. Of note, the phenotype of one patient overlaps with oculo‐auriculo‐vertebral spectrum disorder. 相似文献
85.
Nobuhiko Okamoto Mashiro Nakayama Chie Narahara Han-suk Kim Masashi Fujioka Isao Imada Tatsuya Arai Soichiro Toda 《Journal of human genetics》1997,42(3):441-444
Summary Mevalonic acidemia is a rare metabolic disorder due to mevalonate kinase deficiency which affects the biosynthesis of cholesterol
and nonsterol isoprenes. We report the first case of Japan. The clinical course is characterized by intrauterine growth retardation,
postnatal growth failure, intractable diarrhea, liver dysfunctions and death at three months of age. Dysmorphic features including
triangular face, protrusion of forehead, hypertelorism, low set ears and micrognathism were noted. High mevalonic acid level
was found by GC/MS. 相似文献
86.
目的 探讨三氧化二砷(As2O3)对人肝癌SMMC-7721细胞的生长抑制与P27kipl第187位苏氨酸(P27Thr187)磷酸化的关系.方法 体外培养人肝癌细胞株SMMC-7721,2 μmol/L As2O3处理72 h,细胞计数法检测SMMC-7721生长,流式细胞仪检测细胞周期,核质分离、Western Blot及细胞免疫荧光技术检测P27、Thr187磷酸化的P27(p-P27T187)在SMMC-7721细胞中的表达及亚细胞定位.结果 2 ttmoVL As2O3明显抑制SMMC-7721的增殖,细胞周期阻滞在G2/M期.As2O3作用后P27蛋白总量增加,p-P27T187蛋白总量减少,并伴有Cdk2及cyclinE表达下降,同时P27发生从胞质向胞核的易位,p-P27T187核内表达减少.结论 As2O3可抑制P27T187的磷酸化,诱导P27在SMMCa721细胞核中的积聚. 相似文献
87.
Christopher J. Percival Jay Devine Benjamin C. Darwin Wei Liu Matthijs van Eede R. Mark Henkelman Benedikt Hallgrimsson 《Journal of anatomy》2019,234(6):917-935
Morphometric analysis of anatomical landmarks allows researchers to identify specific morphological differences between natural populations or experimental groups, but manually identifying landmarks is time‐consuming. We compare manually and automatically generated adult mouse skull landmarks and subsequent morphometric analyses to elucidate how switching from manual to automated landmarking will impact morphometric analysis results for large mouse (Mus musculus) samples (n = 1205) that represent a wide range of ‘normal’ phenotypic variation (62 genotypes). Other studies have suggested that the use of automated landmarking methods is feasible, but this study is the first to compare the utility of current automated approaches to manual landmarking for a large dataset that allows the quantification of intra‐ and inter‐strain variation. With this unique sample, we investigated how switching to a non‐linear image registration‐based automated landmarking method impacts estimated differences in genotype mean shape and shape variance‐covariance structure. In addition, we tested whether an initial registration of specimen images to genotype‐specific averages improves automatic landmark identification accuracy. Our results indicated that automated landmark placement was significantly different than manual landmark placement but that estimated skull shape covariation was correlated across methods. The addition of a preliminary genotype‐specific registration step as part of a two‐level procedure did not substantially improve on the accuracy of one‐level automatic landmark placement. The landmarks with the lowest automatic landmark accuracy are found in locations with poor image registration alignment. The most serious outliers within morphometric analysis of automated landmarks displayed instances of stochastic image registration error that are likely representative of errors common when applying image registration methods to micro‐computed tomography datasets that were initially collected with manual landmarking in mind. Additional efforts during specimen preparation and image acquisition can help reduce the number of registration errors and improve registration results. A reduction in skull shape variance estimates were noted for automated landmarking methods compared with manual landmarking. This partially reflects an underestimation of more extreme genotype shapes and loss of biological signal, but largely represents the fact that automated methods do not suffer from intra‐observer landmarking error. For appropriate samples and research questions, our image registration‐based automated landmarking method can eliminate the time required for manual landmarking and have a similar power to identify shape differences between inbred mouse genotypes. 相似文献
88.
安徽省有焦虑症状大学生的社会人口特征及社会心理分析 总被引:4,自引:0,他引:4
目的:了解安徽省大学生焦虑症状流行状况及其社会人口和社会心理影响因素。方法:对所有省属高校按专业分层,以校为整群抽样(每专业1校),抽取该校在校生的15%。采用无记名问卷调查,共获得有效问卷4178份。调查工具包括焦虑自评问卷(SAS)和青少年负性生活事件量表(ASLEC)。结果:6.94%的大学生存在焦虑,其中男生7.22%,女生为6.35%。理工学生焦虑检出率最高(10.08%),西医学生最低(3.59%)。卡方检验显示焦虑症状与社会人口特征中的出生地、年级、学习成绩、专业及父亲学历有关;与社会心理因素中的生活事件与生活经历,家庭环境中的大部分特征都有统计意义的相关性。多元逐步回归模型进一步发现焦虑症状受社会人口特征中理工类专业(OR=1.77,95%CI:1.30~2.41)和成绩差(OR=1.45,95%CI:1.09~1.93)的显著影响,同时也受社会心理因素中的负性生活事件(OR=4.76,95%CI:3.36~6.77)、消极社会经历(OR=3.35,95%CI:2.43~4.62)以及家庭环境特征中的亲密度(OR=0.65,95%CI:0.49~0.85)和情感表达(OR=0.71,95%CI:0.54~0.94)的显著影响。结论:大学生焦虑症状受社会人口特征及社会心理各方面的综合影响,大学生焦虑症状的预防需家庭、学校和社会的共同参与和促进。 相似文献
89.
苦参碱对人单核细胞内三磷酸腺苷结合盒转运体A1及胆固醇酯的影响 总被引:1,自引:0,他引:1
目的观察苦参碱对人单核细胞胆固醇和三磷酸腺苷结合盒转运体A1(ABCA1)表达的影响。方法用TBARS法检测细胞内MDA,油红O染色法检测泡沫细胞的形成,荧光分光光度法检测细胞内总胆固醇、游离胆固醇和胆固醇酯含量,RT-PCR和Western blot检测ABCA1mRNA与蛋白的表达。结果单核细胞经佛波脂(PMA)及ox-LDL共同孵育后,细胞内积聚的总胆固醇、游离胆固醇、胆固醇酯及脂质过氧化产物均明显增多(P<0.05),有大量泡沫细胞形成,而ABCA1蛋白、mRNA水平明显减少(P<0.05);苦参碱干预组显著缓解上述变化,细胞内胆固醇酯减少,ABCA1 mRNA、蛋白表达明显增加(P<0.05)。结论苦参碱可能通过增强ABCA1的表达和降低细胞内胆固醇聚积而发挥抗动脉粥样硬化的作用。 相似文献
90.
Haruo Hagiwara Nobuo Ohwada Takeo Aoki Takeshi Suzuki Kuniaki Takata 《Medical molecular morphology》2008,41(4):221-226
Stromal cells in the lamina propria of the human oviduct mucosa are unique cells that can differentiate into decidual cells
during ectopic pregnancy in the oviduct. The nature of stromal cells is still unknown. In the present study, we investigated
human oviductal stromal cells with transmission electron microscopy and immunohistochemistry and revealed that they had ultrastructural
features similar to myofibroblasts and expressed alpha-smooth muscle actin, a marker used to identify myofibroblasts. Primary
cilia were also one of the characteristic profiles of the stromal cells. These findings showed that the connective tissue-stromal
cells in the human oviduct mucosa are myofibroblasts. They are considered to play an important role in the transport of oocytes
by bringing about contraction of the mucosal folds. 相似文献