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1.
目的 对3例怀疑M蛋白相关性杆状体肌病患者进行肌肉病理检查、M蛋白筛查明确诊断,提高对这一罕见疾病的认识并探讨对此疾病的诊疗方案。 方法 报道3例M蛋白相关性杆状体肌病,结合文献复习对病例特点进行总结。 结果 3例患者均表现为进行性加重的肌肉无力症状,完善肌肉活检诊断为杆状体肌病,合并M蛋白,给予行自体造血干细胞移植治疗有效。 结论 散发的晚发型成人杆状体肌病是一种罕见的、亚急性进展的肌病,常合并M蛋白,针对清除M蛋白的治疗是有效的。  相似文献   
2.
覃凡  李宗平  陈旭  杨旭  夏芹 《西部医学》2022,34(7):1065-1068
目的 探讨高血压性脑出血(HICH)患者血糖波动对其微创碎吸术后血清同型半胱氨酸(Hcy)、血尿酸(UA)水平的影响。方法 选取2018年1月~2020年10月在本院接受微创碎吸术减压治疗的HICH患者125例进行回顾性研究,根据患者是否存在应激性高血糖症(SHG)分为两组,其中61例存在SHG的患者为SHG组,不存在SHG的64例患者为对照组,对比两组患者术后相关参数。结果 两组患者的一般资料比较无统计学差异(均P>0.05),SHG组患者术前血糖高于对照组(P<0.05);SHG组患者住院时间和抗生素应用时间均长于对照组(P<0.05),术前血肿量大于对照组(P<0.05),术后肺炎发生率、6个月死亡率高于对照组(P<0.05),两组患者手术时间、术后再次出血、颅内感染发生率无统计学差异(P>0.05);术后1、3 d的Hcy、UA浓度高于对照组(P<0.05)。结论 高血压性脑出血患者术前存在应激性高血糖症时,其术后预后较差、恢复时间较长,并发症发生率也高于血糖正常者,血清Hcy、UA浓度在短时间内较高,应密切观察患者围术期血清指标,以预测患者病情变化趋势,及时采取预防措施。  相似文献   
3.
BackgroundFour-factor prothrombin complex concentrate 4F-PCC is the standard of care for warfarin reversal in patients with major bleed or requiring urgent surgery. Although the 4F-PCC dose is weight and international normalized ratio (INR) based, for practical purposes, a fixed-dose approach has been explored, especially for rapid reversal. We report our experience using two different fixed-dose 4F-PCC for warfarin reversal in patients presenting with intracranial hemorrhage (ICH).Study design and methodsWe completed a retrospective chart review comparing high (4000 units) versus low (2000 units) dose 4F-PCC by evaluating patient characteristics, laboratory data, and pre-and post-4F-PCC brain imaging.ResultsThere was no significant difference between patient characteristics or INR correction (≤1.5) between the two groups. Eighty percent (12/15) of patients who received the low dose 4F-PCC had either improved or stable brain imaging as compared to 88% (14/16) of patients who received the high dose PCC. When the eight patients (4 from each arm of the study) who required neurosurgery were excluded, only two patients in each arm had worse imaging after 4F-PCC.ConclusionThere was no significant difference between the INR correction and the brain imaging changes in patients with an ICH who received either the high or the low fixed-dose 4F-PCC for warfarin reversal.  相似文献   
4.
目的 观察7.0T MR T2* mapping与T2 mapping检测急性心肌梗死(AMI)再灌注模型大鼠心肌内出血(IMH)的图像质量及其价值。方法 以42只SD大鼠制备AMI再灌注模型,于其后2 d及7 d采集左心室7.0T MR T2* mapping与T2 mapping,获得后处理T2* map与T2 map图;之后处死大鼠,取心脏进行病理检查,评估IMH。观察IMH大鼠各序列原始图像的信噪比(SNR)、对比噪声比(CNR)、图像质量评分及T2* map与T2 map图像的信号均一性。以病理结果为标准,分析2个序列图像检出IMH的效能。结果 造模后2 d (9只)和7 d (16只)后,共25只大鼠造模成功并检出IMH (IMH组),10只存在AMI但无IMH,6只无心肌梗死(无心肌梗死组),另1只在扫描过程中死亡;2 d和7 d IMH组心脏T2 mapping原始图像的SNR>T2* mapping原始图像(P均=0.001),而CNR差异均无统计学意义(P均>0.05)。造模后2 d,IMH组心脏T2 mapping原始图像质量评分(3.90±0.30)高于T2* mapping (3.80±0.40,t=3.67,P<0.01);造模后7 d,T2 mapping原始图像质量评分(3.60±0.50)与T2* mapping差异无统计学意义(3.50±0.50,t=1.65,P=0.10)。IMH组T2 map与T2* map图像的出血心肌及远端心肌的变异系数(COV)差异均无统计学意义(P均>0.05),提示信号均一性无明显差异。T2 mapping及T2* mapping检出IMH的敏感度分别为88.00%(22/25)及96.00%(24/25)。结论 7.0T MR T2* mapping图像信号均一性、SNR及图像质量略低于T2 mapping,二者CNR相当,均可用于检测AMI再灌注大鼠模型IMH。  相似文献   
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6.
Since their inception in the 1960s–70s, mesenchymal stem/stromal cells (MSCs) have gained interest because of their differentiation potential, anti-inflammatory effects, and immune-modulating properties. Both cell-based and cell-free MSC treatments show healing capacity in injured tissues. Cell-based treatment comprises MSCs and all secreted products, whereas cell-free treatments include only the secreted products. MSCs are therapeutically administered to many damaged organs owing to their efficacy. Specifically, the eye is a unique organ system to study the effects of MSCs, as treatment is easily applied and measured owing to its external location. The eye holds an immune-privileged status, wherein inflammation and immune responses are innately down-regulated. As excessive inflammation in the cornea often leads to fibrosis and irreversible corneal hazing, many studies have investigated the anti-inflammatory and immune-modulating capacities of MSCs. Decades of research suggest that MSCs modulate the immune response by secreting cytokines, growth factors, and extracellular matrix proteins that inhibit the infiltration of inflammatory cells following injury and promote a healing phenotype via M2 macrophage polarization. MSCs have also shown trans-differentiation potential into cornea-specific cell types during the wound healing process, such as corneal epithelial, stromal, or endothelial cells. This review discusses recent investigations of MSC treatment in the cornea, focusing on therapeutic efficacy, mechanisms, and future directions.  相似文献   
7.
目的 探究核因子E2相关因子2/谷胱甘肽过氧化物酶4(Nrf2-GPX4)介导的铁死亡通路参与右美托咪定(Dex)对脑出血(ICH)大鼠发挥神经保护作用的机制。方法 将100只SD大鼠按随机数字表法分为Sham组、ICH组(模型组)、Dex-L组(Dex 50 μg/kg)、Dex-H组(Dex 100 μg/kg)、Dex-H+ML385组(Nrf2抑制剂ML385,30 mg/kg),每组20只。除Sham组外,其余组通过自体血注射法建立ICH模型;Dex-L组、Dex-H组及Dex-H+ML385组于术前30 min腹腔注射相应Dex或ML385,Sham组和ICH组则注射等量的生理盐水。术后2 h Zea Longa评分评定大鼠神经功能损伤。试剂盒检测血肿周围脑组织谷胱甘肽(GSH)、丙二醛(MDA)、铁离子含量;称质量检测大鼠血肿周围脑含水量;HE染色、Nissl染色、普鲁士蓝染色分别观察血肿周围脑组织病理学、神经细胞损伤及铁沉积情况;Western blot检测脑组织GPX4、胱氨酸/谷氨酸逆向转运蛋白(xCT)、Nrf2表达。结果 相较于Sham组,神经功能缺损评分、MDA、铁离子含量、脑含水量、脑组织病理损伤、铁沉积在ICH组明显增加,GSH含量、神经细胞数、GPX4、xCT、Nrf2表达水平明显减少(均P<0.05);相较于ICH组,神经功能缺损评分、MDA、铁离子含量、脑含水量、脑组织病理损伤、铁沉积在Dex-L组与Dex-H组依次明显降低,GSH含量、神经细胞数、GPX4、xCT、Nrf2表达水平明显增加(均P<0.05);ML385可逆转Dex-H对神经功能、铁沉积、脑损伤的改善。结论 Dex通过激活Nrf2-GPX4通路来抑制铁死亡,从而对ICH大鼠发挥神经保护的作用。  相似文献   
8.
Obesogens are a subset of endocrine disruptor chemicals (EDCs) that cause obesity. The typical EDC 4-nonylphenol (4-NP) has been identified as an obesogen. However, the in vitro effects of 4-NP on adipogenesis remain unclear. In this study, 3T3-L1 preadipocytes and C3H/10T1/2 mesenchymal stem cells (MSCs) were used to investigate the influence of 4-NP on adipogenesis. The differentiation protocols for 3T3-L1 preadipocytes and C3H/10T1/2 MSCs took 8 and 12 days, respectively, beginning at Day 0. In differentiated 3T3-L1 preadipocytes, 20 μM 4-NP decreased cell viability on Days 4 and 8. Exposure to 4-NP inhibited triglyceride (TG) accumulation and adipogenic marker expression on Days 0–8, but the inhibitory effects were weaker on Days 2–8. The protein expression of pSTAT3 or STAT3 decreased on Days 0–8 and 2–8. Conversely, 4-NP promoted TG accumulation and the adipogenic marker expression in C3H/10T1/2 adipocytes. The opposing effects were attributed to physiological differences between the two cell lines. The 3T3-L1 preadipocytes are dependent on mitotic clonal expansion (MCE) to drive differentiation, while C3H/10T1/2MSCs and human preadipocytes are not. Additionally, 4-NP downregulated β-catenin expression in C3H/10T1/2 adipocytes. Accordingly, we hypothesized that 4-NP promotes adipogenesis. The role of the canonical Wnt pathway in the promotion of adipogenesis by 4-NP requires further validation. This study provides new insights into the mechanisms and appropriate risk management of 4-NP.  相似文献   
9.
《Immunobiology》2022,227(3):152211
ObjectiveThe present study was intended to investigate the role of embryonic stem cell-derived exosomes (ESC-Exos) in Müller cell retrodifferentiation and their specific mechanism.MethodsFollowing co-incubation of the extracted ESC-Exos and Müller cells, their effects on the retrodifferentiation and proliferation of Müller cells were measured by EdU staining, immunofluorescence, and western blot. ESCs transfected with small interfering RNA of BDNF were co-incubated with Müller cells to determine Müller cell proliferation and retrodifferentiation. β-catenin expression in the nucleus and GSK-3β phosphorylation were measured to determine the role of the Wnt pathway in Müller cells. The function of the retina in RCS rats was observed using flash electroretinogram.ResultsCo-incubation of ESCs with Müller cells or overexpression of BDNF contributed to Müller cell retrodifferentiation and proliferation, as evidenced by increased cell proliferation, fluorescence intensities of proliferation markers and retinal stem cell markers, and expression of BDNF and β-catenin, and suppressed GSK-3β phosphorylation. However, co-incubation with ESCs silencing BDNF or treatment with GW4869 inhibited the proliferation and retrodifferentiation of retinal Müller cells. In addition, exosome injection increased BDNF, BrdU, PH3, SOX2, and Pax6 expression, enhanced β-catenin expression in the nucleus, diminished GSK-3β, and improved retinal degeneration in RCS rats.ConclusionESC-Exos accelerated Müller cell retrodifferentiation and proliferation through Wnt pathway activation by delivering BDNF protein to Müller cells.  相似文献   
10.
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