Association of distal hyperintense vessel sign and recurrent stroke in patients with symptomatic intracranial stenosis

ObjectiveThe distal hyperintense vessel sign (DHV) on fluid-attenuated inversion recovery magnetic resonance image (MRI) is an imaging biomarker of slow leptomeningeal collateral flow in the presence of large artery stenosis or occlusion reflecting impaired cerebral hemodynamics. In this study, we aim to investigate the significance of the DHV sign in patients with symptomatic ≥ 70% intracranial atherosclerotic stenosis.MethodsWe retrospectively reviewed patients with ischemic stroke or transient ischemic attack admitted to a single center from January 2010 to December 2017. Patients were included if they had symptomatic ≥ 70% atherosclerotic stenosis of the intracranial internal carotid artery or middle cerebral artery. The presence of the DHV sign was evaluated by blinded neuroradiologist and vascular neurologists. Recurrent ischemic stroke in the vascular territory of symptomatic intracranial artery was defined as new neurological deficits with associated neuroimaging findings during the follow up period.ResultsA total of 109 patients were included in the study, of which 55 had DHV sign. Average duration of follow up was 297 ± 326 days. Four patients were lost during follow up. Patients with the DHV sign had a higher rate of recurrent ischemic stroke (38%), compared to patients without the DHV sign (17%; p=0.018). In multivariate regression analysis, the presence of DHV sign was an independent predictor of recurrent ischemic stroke. A DHV score of ≥ 2 had a 63% sensitivity and 69% specificity for recurrent ischemic stroke.InterpretationIn patients with severe symptomatic intracranial atherosclerotic stenosis, those with a DHV sign on MRI are at higher risk of recurrent ischemic stroke.     

镫骨骨质缺损对听力传导影响的有限元分析

目的建立完善的鼓膜-听骨链模型,利用有限元初步探讨镫骨前、后脚骨质缺损对听力传导的影响。方法实验数据源于对一名无中耳病史的成年男性左侧颞骨进行Micro-CT扫描,在医学影像处理软件Mimics上进行三维重建,利用Geomagic形成需要的曲面,最后在SolidWorks上将成型的鼓膜-听骨链模型进行切割组装,建立正常听骨链模型以及镫骨前、后脚骨质缺损模型,利用模型分析骨质缺损对听力传导的影响。结果建立的鼓膜-听骨链模型镫骨足板频振曲线符合相关文献报道,在镫骨前、后脚骨质缺损病理模型下,曲线与正常中耳模型曲线接近。结论利用多软件综合处理,可建立可信度较高的中耳听骨链模型;有限元模拟分析结果显示,镫骨前、后脚缺损部分骨质,未对听力传导产生明显影响。     

Avoiding iatrogenic vascular injury in tibial external fixation with half pins. An in-vivo study based on CT angiography

BackgroundExternal fixation is an important tool in the management of variety of tibial fractures. Appropriate half pin insertion is important, to provide stable fixation without compromising the surgical field for definitive surgical procedures, and avoiding further damage to the important structures of the traumatized limb. There is paucity of literature about the optimal trajectories and safe corridors for half pins insertion based on in vivo studies. The available studies are based on anatomic atlases, cadaveric studies or half pin related complications.The aim of the current study is to present the findings of CT angiograms, in patients with external fixation of tibia, to enhance our understanding of optimal trajectories in safe corridors for half pins insertion.Material and methodsWe performed a retrospective study of patients with external fixators on the tibia, who had undergone CT angiogram as part of pre-operative planning for orthoplastic reconstructive procedures. The relationship between the tips of the fixator half pins and named vessels of the leg were analyzed, pins within 5 mm of a named vessel were considered to be a risk of causing iatrogenic injury.ResultsA total 51 patients, with in situ temporizing external fixators, with 134 half pins in different segments of the tibia were analyzed. More than 5 mm of penetration beyond the far cortex was noted in 47%, while in another 16% of pins penetration was more than 10 mm beyond the cortex. A tip to vessel distance (TVD) of 5 mm or less was noted in 28/134 (21%) of the pins, which highlights potential risk to the neurovascular bundles of the leg.ConclusionRisk of iatrogenic injury to neurovascular structures from half pin insertion can be reduced by meticulous use of fluoroscopy, by avoiding penetration beyond the far cortex, and avoiding exiting with half pins on the lateral surface in the distal 1/3rd of segment II of tibia. Moreover observing optimal trajectories and safe corridors for pin insertion, and selection of appropriate type of half pin can mitigate the risk to these structures.     

Myelodysplastic/myeloproliferative neoplasms: are morphology and immunophenotyping still relevant?

The term myelodysplastic/myeloproliferative neoplasm (MDS/MPN) refers to a group of clonal hematopoietic neoplasms with overlapping clinical, morphologic and genetic myelodysplastic and myeloproliferative features observed at the time of first presentation. Impaired hematopoiesis morphologically associated with evidence of myelodysplasia manifests clinically with cytopenia/s. Simultaneously, myeloproliferation is seen within the bone marrow and leads to cytosis in the peripheral blood.The diagnostic category of MDS/MPN encompasses a heterogeneous group of diseases which share similarities among them, but at the same time have distinct clinical and pathologic features and eventually diverse prognosis; such differences justify their separation in a classification scheme.In the era of genetic and genomic tests, their distinction from conventional myelodysplastic syndromes or myeloproliferative neoplasms still relies on close clinocopathological correlation, with evaluation of both peripheral blood and bone marrow samples being essential in this sense. A multiparametric integration of clinicopathologic data and cytogenetics and molecular genetics results is the preferred diagnostic approach.     

COPD患者相关炎性因子水平与其病情严重程度的相关性研究

探讨慢性阻塞性肺病(COPD)患者的可溶性髓系细胞触发受体-1(sTREM-1)、结缔组织生长因子(CTGF)、亲环素-A(CyPA)水平与其病情严重程度的相关性。ELISA检测COPD患者与健康人血清sTREM-1、CTGF、CyPA水平。结果显示,COPD患者sTREM-1、CTGF、CyPA水平高于健康人。随着肺功能分级的增加,COPD患者血清中sTREM-1、CTGF、CyPA水平也随之增加。sTREM-1、CTGF、CyPA水平与FEV1/FVC呈现显著负相关性(P＜0.05)。Logistic回归分析显示,sTREM-1、CTGF、CyPA水平是严重COPD的影响因素。结果说明,COPD患者血清sTREM-1、CTGF、CyPA水平显著升高,并且与患者肺功能指标显著相关,可用于判断COPD患者的病情严重程度。     

保留足趾的自体复合第2足趾关节移植治疗手指关节炎

目的 探讨保留足趾的自体复合第2足趾关节移植治疗手指关节炎的临床疗效.方法 2016年2月至2018年6月,共收治创伤性手指关节炎9例,其中男7例,女2例;年龄19~53岁,平均31.7岁;示指3例,中指6例;掌指关节(MP)关节炎4例,近侧指骨间关节(PIP)关节炎5例;均为创伤后继发的手指关节炎.采用游离带血供的自体复合第2足趾跖趾或趾骨间关节移植进行治疗,同时将受区废弃关节(7例)或切取自体髂骨移植(2例)修复供区骨缺损保留足趾长度,供区创面均直接关闭.术后观察手指和足趾骨折愈合情况、外形、移植关节活动度(ROM)、术后供区愈合情况和行走功能及相关并发症.结果 本组术后9例移植关节全部成活,1例足部供区行髂骨植骨微型钢板固定,术后1周伤口不愈合,考虑为内固定物排异反应,予拆除钢板改克氏针交叉固定,2周后创口顺利愈合.术后随访6~30个月,平均16.3个月.手指骨折平均愈合时间7~10周,平均8.3周,手指外观及功能良好.移植后的MP活动度为50°~75°,平均65.3°,PIP活动度为10°~85°,平均60.6°.根据中华医学会手外科学分会上肢部分功能评定试用标准评价手指功能:优5例,良3例,可1例,优良率为88.9%.足趾骨折平均愈合时间9~12周,平均10.2周,所有患者足趾外形良好,行走功能正常.2例取髂骨患者供区仅残留一条线形瘢痕,无疼痛、麻木等不适.结论 游离带血供的自体复合第2足趾关节移植治疗手指关节炎,同时应用受区废弃关节或切取自体髂骨移植修复供区骨缺损保留足趾,不仅能恢复手指关节的正常结构,使关节具有良好的功能,而且能保留足趾外形与功能,减少供区损伤,具有良好的治疗效果.     

Mesenchymal stem cells from orthodontic premolar teeth

BackgroundConsidering the limitations in isolating Bone Marrow Mesenchymal Stem Cells (BMSCs), alternate sources of Mesenchymal Stem Cells (MSCs) are being intensely investigated. This study evaluated dental pulp MSCs (DP-MSCs) isolated from orthodontically extracted premolar teeth from a bone tissue engineering perspective.MethodsMSCs isolated from premolar teeth pulp were cultured and studied using BMSCs as the control. Flow cytometry analysis was performed for the positive and negative MSC markers. Multilineage differentiation focusing on bone regeneration was evaluated by specific growth induction culturing media and by alkaline phosphatase (ALP) activity. Data were compared by repeated measurement analysis of variance and Student's t-test at a p value <0.05.ResultsProliferation rate, population doubling time, and colony formation of DP-MSCs were significantly higher (p < 0.001) than BMSCs. More than 85% of DP-MSCs expressed CD44, CD73, CD90, CD105, and CD166. Negative reaction was found for CD11b CD33, CD34, and CD45. Positive reaction was displayed by 7.2% of cells for early MSC marker, Stro-1. Both the cell populations differentiated into adipogenic, osteogenic, and chondrogenic lineages, with adequate ALP expression.ConclusionBecause DP-MSCs from orthodontic premolars hold a neural crest/ectomesenchymal ancestry, its prudent growth characteristics and multilineage differentiation open up exciting options in craniofacial tissue engineering.     

槽型鞘脑穿刺针的设计及动物实验初步结果

目的测试槽型鞘脑穿刺针用于实验动物脑组织穿刺的可操作性和安全性。 方法新西兰兔6只，麻醉后骨窗开颅显露双侧大脑半球，左侧大脑半球以传统脑穿刺针进行穿刺，右侧以槽型鞘脑穿刺针穿刺，完成穿刺、拔出穿刺针留置槽形鞘、置管后拔出槽形鞘等步骤。拔出穿刺针后穿刺道以苏木素染色，观察30 min后处死实验动物，提取脑组织，沿脑组织穿刺道制3 μm厚切片，常规HE染色，显微镜下观察脑组织穿刺道病理解剖学变化（脑组织破损及出血情况），评估损伤程度。 结果2种穿刺针穿刺操作后均会造成穿刺道局灶性脑挫裂伤，表现为穿刺道组织缺损、脑组织淤血、水肿。光镜下可见穿刺道脑组织破碎、细胞排列不规则、水肿的细胞体增大和细胞核固缩，穿刺道外围细胞结构正常。2种穿刺针针道脑组织病理特征差别不明显。 结论槽型鞘脑穿刺针穿刺操作简便，通过槽型鞘置入引流管方便，脑组织损伤程度与传统脑穿刺针无明显差别。