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1.
《European journal of medical genetics》2022,65(6):104495
Spondyloepimetaphyseal dysplasias (SEMDs) belong to a clinically and genetically heterogeneous group of inherited skeletal disorders defined by a defect in the growth and shape of vertebrae, epiphyses and metaphyses. Rhizomelic SEMD is characterized by a disproportionate small stature caused by severe shortening and deformation of the limbs’ proximal bones, with the cranio-facial sphere unaffected. We report a second individual, an 8-year-old girl, with autosomal recessive rhizomelic SEMD associated with a homozygous exonic missense variant, c.226G > A p.(Glu76Lys), in GNPNAT1 identified by trio genome sequencing. Our data corroborate the recent findings of Ain et al. and further delineate the clinical and radiographic features of this form of SEMD associated with rhizomelic dysplasia while outlining a potential hotspot in this newly described genetic disorder. 相似文献
2.
《Biomaterials》2015
The chemical composition, structure and surface characteristics of biomaterials/scaffold can affect the adsorption of proteins, and this in turn influences the subsequent cellular response and tissue regeneration. With magnesium/calcium phosphate cements (MCPC) as model, the effects of magnesium (Mg) on the initial adhesion and osteogenic differentiation of bone marrow stromal cells (BMSCs) as well as the underlying mechanism were investigated. A series of MCPCs with different magnesium phosphate cement (MPC) content (0∼20%) in calcium phosphate cement (CPC) were synthesized. MCPCs with moderate proportion of MPC (5% and 10%, referred to as 5MCPC and 10MCPC) were found to effectively modulate the orientation of the adsorbed fibronectin (Fn) to exhibit enhanced receptor binding affinity, and to up-regulate integrin α5β1 expression of BMSCs, especially for 5MCPC. As a result, the attachment, morphology, focal adhesion formation, actin filaments assembly and osteogenic differentiation of BMSCs on 5MCPC were strongly enhanced. Further in vivo experiments confirmed that 5MCPC induced promoted osteogenesis in comparison to ot her CPC/MCPCs. Our results also suggested that the Mg on the underlying substrates but not the dissolved Mg ions was the main contributor to the above positive effects. Based on these results, it can be inferred that the specific interaction of Fn and integrin α5β1 had predominant effect on the MCPC-induced enhanced cellular response of BMSCs. These results provide a new strategy to regulate BMSCs adhesion and osteogenic differentiation by adjusting the Mg/Ca content and distribution in CPC, guiding the development of osteoinductive scaffolds for bone tissue regeneration. 相似文献
3.
This study aimed to observe the therapeutic effects of magnesium lithospermate B on acute and chronic colitis induced by dextran sodiumsulfate (DSS) and the role of inflammasome complex (NOD-like receptor protein, NLRP; apoptosis-associated speck-like protein containing, ASC; caspase-1). Establishment of acute and chronic colitis models were by using 5% DSS oral administration in BALB/C male mice. Magnesium lithospermate B (240 mg/kg body weight) was given by subcutaneous injection. Samples were collected for biomarker assay, histological examination, immunohistochemical evaluation and western blot. There was obvious increase in TNF-α level and NLPR3, ASC, and caspase-1 expressions in acute and chronic colitis groups compared with the normal control. Significant decrease of the tumor necrosis factor-α level and the expressions of NLPR3, ASC, and caspase-1 were observed after treatment with magnesium lithospermate B. This study showed that magnesium lithospermate B could be used to treat acute and chronic colitis by inhibiting the activation of the NLRP3/ASC/Caspase-1 pathway. 相似文献
4.
《药学学报(英文版)》2020,10(7):1294-1308
A great challenge in multi-targeting drug discovery is to identify drug-like lead compounds with therapeutic advantages over single target inhibitors and drug combinations. Inspired by our previous efforts in designing antitumor evodiamine derivatives, herein selective histone deacetylase 1 (HDAC1) and topoisomerase 2 (TOP2) dual inhibitors were successfully identified, which showed potent in vitro and in vivo antitumor potency. Particularly, compound 30a was orally active and possessed excellent in vivo antitumor activity in the HCT116 xenograft model (TGI = 75.2%, 150 mg/kg, p.o.) without significant toxicity, which was more potent than HDAC inhibitor vorinostat, TOP inhibitor evodiamine and their combination. Taken together, this study highlights the therapeutic advantages of evodiamine-based HDAC1/TOP2 dual inhibitors and provides valuable leads for the development of novel multi-targeting antitumor agents. 相似文献
5.
目的探讨对妊娠高血压综合征患者给予硫酸镁联合硝苯地平以及酚妥拉明治疗的临床效果。方法抽取医院在2018年2月-2019年2月所接收的156例妊娠高血压综合征患者,将其按照数字随机表的方法分为单纯组和联合组,每组分别为78例。单纯组给予单纯的硫酸镁进行治疗,联合组在单纯组给予硝苯地平以及酚妥拉明进行联合治疗,比较患者的治疗效果。结果联合组的治疗有效率显著高于单纯组,治疗前血压水平差异无统计学意义(P>0.05),治疗后联合组的收缩压和舒张压水平均低于单纯组,P<0.05,两组差异有统计学意义。结论对妊娠高血压综合征患者给予硫酸镁联合硝苯地平和酚妥拉明进行联合治疗,有效改善患者的血压水平。 相似文献
6.
7.
目的 建立小鼠溃疡性结肠炎模型。方法 给小鼠自由饮用5%葡聚糖硫酸钠(DSS)溶液7d后,改为蒸馏水自由饮用10d,如此进行4个循环,每天观察症状。在第1个循环和第4个循环后剖杀小鼠,取出整段结肠行实体显微镜观察及切片组织学研究。结果 所观察的症状、实体显微镜像、组织学病理改变均与人类溃疡性结肠炎类似。结论 此模型制作方法简便,重复性良好,可应用于多种实验研究。 相似文献
8.
Platelet factor 4 ( PF4) is a negativehematopoietic factor.It can inhibit the prolifera-tion of endothelial cells and hematopoietic stem/progenitor cells,particularly megakaryoryocyticcells,reversibly[1] ,inhibit DNA synthesis,blockcell cycle progression during S phase and reducethe sensibility of normal hematopoietic stem/pro-genitor cells,but not some cancer or leukemia celllines,to cytotoxic drugs and ionizing radia-tion[2 - 3] ,and it also can cause a population in-crease of the stem cel… 相似文献
9.
Objective Based on the Helical Ventricular Myocardial Band (HVMB) theory proposed by Torrent-Guasp,the ventricular myocardial hand extends from the root of the pulmonary artery to the root of the aorta with two helical coils.This new theory is considered as a revolutionary concept for further understanding the global, three-dimensional and functional architecture of the ven- tricular myocardium. No repot had described techniques for disecting HVMB while keepin~ the integrity of the coronmy artery sys- tern. We explored techniques for dissecting HVMB in swine.Methads 33 fresh swine hearts were randomly divided intoll groups, 3 bearts in each. 160% barium sulfate (type I)suspmmion was injected into the coronary artery system. The coronary arteries were li- gated. The strial tissue was removed following puuing the hearts in boiling water then cooling for several hours. The superficial coro- nary vessels and fat tissue around the atrio-ventricular taxi inter-ventricular sulcus we~'e preserved. Some branches of the left anterior descending artery, distal segment, of posterior descending branch, and middle and distal segment of obtuse marginal branches were mu- tilated appropriately. HVMB dissection was completed with fingers in accordnce with Torrent Guasp' s technique. Results A contin- ued bundle of muscle, originated at the root of pulmonary artery and ended at the root of aorta, was unwrapped along the major dire- tion of the cardiac muscle fiber in all of the 33 hearts with spating of the coronary artery. The swine hearts' ventricular myocandium was cumosed of two loops, with basal loop firm the root of the pulmonart artery to the anterior papillary muscle and apical from the beginning of the anterior papillary muscle to the root tithe aorta. Each loop consisted of two segments: the right segment-coincid- ing with the right ventricular free wall and the left segment-coinciding with the basal d the left ventricular free wall. Posterior papillary muscle, which belongs to the descendant segment, denmrcated the border between the descendent and the ascendant of the HVMB's apical loop. Conclusion Although controversies about the theory of the HVMB remain, we have dissected the HVMB in the swine hearts' ventricular myocardium successfully with sparing of the coronary artery systems. This dissection procedure provides technical information for the studies of associated diseases based on the theory of HVMB. 相似文献
10.
Breuer J.; Moniz C.; Baldwin D.; Parsons V. 《Nephrology, dialysis, transplantation》1987,2(5):347-350
The effect of oral magnesium carbonate aluminium hydroxide onserum ionised calcium, total calcium, aluminium and magnesium,was assessed in 31 patients with chronic renal failure, duringand after one haemodialysis. The behaviour of ionised calcium and total calcium was the samein both groups. Each showed a slight fall during dialysis, whichwas not significant. Serum total calcium was 0.20.3 mmol/l(0.81.2 mg/dl) greater throughout the period of dialysisin the group taking aluminium hydroxide. Serum magnesium andaluminium were both lower in the group treated with magnesiumcarbonate. In the group taking magnesium carbonate, serum magnesium concentrationsfell markedly during dialysis, but otherwise were maintainedwithin the reference range by the use of a magnesium-free dialysate.These results show the effectiveness of magnesium carbonateoral phosphate-binding agents and zero magnesium dialysate inreducing serum aluminium without affecting the behaviour ofserum calcium fractions during dialysis. 相似文献