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Contiguous ABCD1 DXS1357E deletion syndrome (CADDS) is a contiguous deletion syndrome involving the ABCD1 and DXS1357E/BAP31 genes on Xq28. Although ABCD1 is responsible for X‐linked adrenoleukodystrophy (X‐ALD), its phenotype differs from that of CADDS, which manifests with many features of Zellweger syndrome (ZS), including severe growth and developmental retardation, liver dysfunction, cholestasis and early infantile death. We report here the fourth case of CADDS, in which a boy had dysmorphic features, including a flat orbital edge, hypoplastic nose, micrognathia, inguinal hernia, micropenis, cryptorchidism and club feet, all of which are shared by ZS. The patient achieved no developmental milestones and died of pneumonia at 8 months. Biochemical studies demonstrated abnormal metabolism of very long chain fatty acids, which was higher than that seen in X‐ALD. Immunocytochemistry and Western blot showed the absence of ALD protein (ALDP) despite the presence of other peroxisomal proteins. Pathological studies disclosed a small brain with hypomyelination and secondary hypoxic‐ischemic changes. Neuronal heterotopia in the white matter and leptomeningeal glioneuronal heterotopia indicated a neuronal migration disorder. The liver showed fibrosis and cholestasis. The thymus and adrenal glands were hypoplastic. Array comparative genomic hybridization (CGH) analysis suggested that the deletion was a genomic rearrangement in the 90‐kb span starting in DXS1357E/BACP31 exon 4 and included ABCD1, PLXNB3, SRPK3, IDH3G and SSR4, ending in PDZD4 exon 8. Thus, the absence of ALDP, when combined with defects in the B‐cell antigen receptor associated protein 31 (BAP31) and other factors, severely affects VLCFA metabolism on peroxisomal functions and produces ZS‐like pathology.  相似文献   
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目的:研究鸟胞内分枝杆菌复合群(MAC)MAV3104基因编码蛋白与药物外排的关系。方法以MAC 标准株基因组为模板,扩增 MAV3104基因,构建 pMV261-MAV3104c 重组质粒;测序正确后,转化重组质粒到大肠杆菌 DH5并在 MAC 标准株中诱导表达,Western Blot 鉴定 MAV3104表达;按照 CLSIM24-A2的操作要求检测 MAC标准株对克拉霉素的敏感性及外排泵抑制试验。结果经基因测序及 Western Blot 蛋白表达验证重组质粒构建成功;MAV3104过表达能提高鸟分枝杆菌对克拉霉素的 MIC,且硫利达嗪能抑制该作用;MAV3104过表达也能提高胞内分枝杆菌对克拉霉素的 MIC,但硫利达嗪对其没有抑制效应。结论 MAV3104转运蛋白介导的药物外排在鸟分枝杆菌耐克拉霉素中起重要作用。  相似文献   
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Background

Atopic dermatitis is a chronic and severe pruritic skin disease. Interlukin-31 (IL-31) has been recently demonstrated to be one of the key pruritogens in atopic dermatitis. However, the mechanisms underlying IL-31-induced itching remains unclear. In our previous study, we have shown that thromboxane (TX) A2 is involved in itch-associated responses in mice with atopy-like skin diseases.

Methods

IL-31 was given intradermally into the rostral back of ICR mice and the hind-paw scratching to the injection site were counted. Expression of TX synthase and IL-31 receptors were analyzed using immunohistochemical staining or RT-PCR in mouse skin or primary cultures of mouse keratinocytes. The concentration of TXB2, a metabolite of TXA2, in the skin and the culture medium of primary cultures of mouse keratinocytes was measured using enzyme immunoassay. The concentration of intracellular Ca2+ ions in mouse keratinocytes was measured using the calcium imaging method.

Results

An intradermal injection of IL-31 elicited scratching, an itch-related response, in mice. The scratching was inhibited by TP TXA2 receptor antagonist DCHCH. The distribution of TX synthase and IL-31RA receptor was mainly epidermal keratinocytes in the skin. The primary cultures of keratinocytes expressed the mRNAs of TX synthase and IL-31 receptors. IL-31 increased the concentration of TXB2, which was inhibited by TX synthase inhibitor sodium ozagrel and EGTA, in the skin and the culture medium of primary cultures of keratinocytes. IL-31 increased the concentration of intracellular Ca2+ ions in mouse keratinocytes.

Conclusion

It is suggested that IL-31 elicits itch-associated responses through TXA2 produced from keratinocytes.  相似文献   
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目的探讨miR-363-5p靶向三结构域蛋白14(TRIM14)对3种乳腺癌细胞系凋亡的影响。 方法采用实时荧光定量PCR法比较不同化疗药物诱导3种乳腺癌细胞(MCF-7、MDA-MB-435、MCF-12A)中miR-363-5p和TRIM14 mRNA表达水平,采用免疫组化法检测不同亚型乳腺癌组织TRIM14表达情况。采用Western blotting检测TRIM14蛋白表达。采用流式细胞术检测细胞凋亡情况。应用生物信息学方法预测miR-363-5p与TRIM14的结合位点,通过干扰miR-363-5p和TRIM14研究miR-363-5p对3种乳腺癌细胞中TRIM14的调控作用。Pearson相关分析各亚型乳腺癌组织中miR-363-5p与TRIM14的相关性。 结果3种化疗药物均能促进细胞凋亡,化疗药物处理3种亚型乳腺癌细胞后miR-363-5p表达上升,TRIM14 mRNA表达下降。荧光素酶报告基因实验发现TRIM14是miR-363-5p的靶基因。过表达miR-363-5p后,3种亚型乳腺癌细胞凋亡率上升,TRIM14蛋白和mRNA下降。敲低TRIM14后3种亚型乳腺癌细胞凋亡率上升,过表达TRIM14后3种亚型乳腺癌细胞凋亡率下降。3种亚型乳腺癌组织miR-363-5p与TRIM14表达呈负相关。 结论化疗药物诱导3种亚型乳腺癌细胞后miR-363-5p表达上升,miR-363-5p靶向抑制TRIM14表达,促进3种乳腺癌细胞系凋亡。  相似文献   
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