MR脂肪抑制技术在肌肉骨骼系统的临床应用进展

肌肉骨骼系统磁共振成像(MRI)常应用脂肪抑制技术，抑制背景脂肪信号，清楚显示病变及其信号特征，减少伪影，提高图像质量。本文综述了脂肪抑制技术在肌肉骨骼系统疾病诊断中的应用进展。     

Coronal oblique turbo STIR imaging of the sacrum and sacroiliac joints at routine MR imaging of the lumbar spine

The objective of the study was to evaluate the clinical impact of coronal oblique imaging of the lumbrosacral junction and the sacrum at initial presentation for MR imaging of the lumbar spine in patients presenting with low back pain or sciatic pain. Two hundred and sixty consecutive patients attending for MRI of the lumbar spine underwent simultaneous coronal oblique turbo short tau inversion recovery (STIR; TR 2500, TE 40, TI 150, echo train length 7, number of scan acquisitions 2) imaging of the sacrum and the sacroiliac joints with a field of view of 30-cm and 3-mm slices (acquisition time 3 min and 20 s). Images were reviewed by two experienced radiologists to determine the cause of back pain, with and without images of the sacrum and sacroiliac joints. The added value of the additional sequence was assessed. Correlation was made with surgery, response to nerve root injection or clinical follow-up at 3 months. Subgroup analysis was performed to determine if patient stratification according to sex or symptoms would be useful. In total, in 19 of 260 patients (7.3%), abnormalities were identified at coronal STIR imaging. In 7 of 260 patients (2.7%), pathology was identified in the sacrum thought to account for back pain, altering the diagnosis made on the standard sequences. These diagnoses were sacroiliitis (n=2), sacral stress fracture (n=1), degenerative sacroiliac joints (n=1), degenerative accessory articulation between the lumbar spine and the sacrum (n=1), Tarlov cyst of nerve root (n=1) and retroverted uterus causing sciatic pain (n=1). Patient stratification according to sex or the presence or absence of sciatic symptoms was not useful in predicting the added benefit of the additional sequence. Routine coronal STIR imaging of the sacrum as part of lumbar spine MRI improves assessment of patients presenting with low back pain or sciatica in only a small number of patients.     

Changes in serum lipoproteins in humans following the infusion of a fat emulsion containing medium- and long-chain triglycerides

Abstract. A fat emulsion containing equal parts of medium-chain triglycerides (MCT) and long-chain triglycerides (LCT) and emulsified with egg phospholipids (Lipofundin MCT 10%®) was compared with LCT emulsions (Intralipid 10%®, egg phospholipids; Lipofundin S 10%®, soya phospholipids) in six volunteers, using 4-h periods of infusion and doses of 0·15 g kg^-1 body h^-1. At the end of infusion very low density lipoprotein (VLDL) triglyceride concentrations were highest with Intralipid, marginally less with Lipofundin MCT and lowest with Lipofundin S. With Lipofundin MCT infusion the proportions of free mediumchain fatty acids in serum reached 30%. In VLDL the ratios triglycerides/apolipoprotein B and triglycerides/phospholipids rose most after Lipofundin MCT and least after Lipofundin S. With Lipofundin MCT and Intralipid, surface components in low density lipoproteins (LDL) are lessened in relation to the internal components; this does not occur with Lipofundin S. High density lipoprotein (HDL) subfractions are influenced in identical directions by all fat emulsions with exception of a single increase of phospholipids in (HDL₃) after Lipofundin MCT.     

MR脂肪定量技术在腰椎椎体骨髓脂肪含量评估中的研究进展

骨髓是人体内重要的造血和免疫器官,其内脂肪含量的变化对于疾病的精准诊断和疾病严重程度的分级至关重要。由于MRI对软组织和脂肪组织等具有较好的分辨力,因而对骨髓脂肪含量的定量评估起着不可替代的作用。就扩散加权成像、磁共振波谱成像、化学位移成像以及水脂分离技术等MR脂肪定量技术在腰椎椎体骨髓脂肪含量定量评估方面的应用及研究进展予以综述。     

Human acute pancreatitis: Its pathogenesis in the light of immunocytochemical and ultrastructural findings in acinar cells

Summary Human acute pancreatitis results from an autodigestive process frequently associated with alcohol abuse, gall stone disease and shock. Peripancreatic fat necrosis was identified as one of the earliest visible lesions, whereas acinar cell necrosis and haemorrhage were regarded as secondary changes. To examine the alterations in acinar cells in more detail, their enzyme content and fine structural features were studied immunocytochemically using antisera against -amylase, lipase, trypsin, chymotrypsin and pancreatic stone protein, and electronmicroscopically in pancreatic tissues from patients with severe acute pancreatitis. Peripheral acinar cells in the immediate vicinity of fat necrosis were found to be heavily degranulated, while acinar cells at some distance of necrosis fully retained their enzyme content. Other frequent changes of the acinar cells included cuboidal transformation, loss of microvilli, increased occurrence of autophagosomes, and formation of enlarged acinar lumina. As there was no apparent cell membrane leakage or rupture of duct lumina, it is concluded that the acinar cells adjacent to fat necrosis release their granules by undirected basolateral extrusion. The findings thus suggest that one of the basic defects in acute pancreatitis is the uncontrolled release of enzymes from peripheral acinar cells into the interstitial space which, in turn, presumably by the action of lipase, leads to autodigestive fat necrosis.Dedicated to Prof. Dr. G. Seifert on the occasion of his 65th birthdayPresented in part at the Second International Symposium on the Classification of Pancreatitis, Marseille, 1984, and at the Meeting of the European Pancreatic Club, Manchester, 1985     

Superovulation with urinary human follicle-stimulating hormone: correlations with body mass index and body fat distribution

Our objective was to i nvestigate the relationship between body mass index (BMI), waist/hip ratio (WHR), follicle-stimulating hormone (FSH) dose, length of stimulation and clinical outcome in infertile women with and without polycystic ovary syndrome (PCOS) undergoing controlled ovarian hyper stimulation.

Controlled ovarian hyperstimulation was induced in 60 women for a total of 111 cycles (48% in PCOS patients) with urinary human FSH (u-hFSH).

A significant correlation between BMI, u-hFSH dose and duration of stimulation was found in PCOS and non-PCOS patients with WHR < 0.8. These correlations were not present in PCOS patients with WHR > 0.8. Pregnant patients received significantly less ampules ofu-hFSH.

From our data we suggest a controlled ovarian hyperstimulation protocol, for obese non-PCOS patients and obese PCOS patients with WHR < 0.8, starting with a double dose of u-FSH.     

肝细胞生长因子基因转染骨髓间充质干细胞对脂肪颗粒移植存活率的影响

目的研究携带人肝细胞生长因子基因的重组腺病毒（Ad—HGF）修饰骨髓间充质干细胞（MSCs）对大鼠脂肪颗粒移植存活率的影响。方法用携带绿色荧光蛋白的重组腺病毒（Ad-GFP）、Ad—HGF转染雄性Wistar大鼠MSCs,测定转染效率与感染上清中肝细胞生长因子（HGF）的表达。用雌性Wistar大鼠150只,随机分为5组：空白对照组（A组）、Ad—HGF组（B组）、MSCs组（C组）、Ad—GFP感染MSCs组（D组）和Ad—HGF感染MSCs组（E组）,每组30只。各组均匀振动5分钟,将颗粒脂肪移植于自体背部皮下;移植后3、5、7、14、28、60d,每组各取5只大鼠脱颈处死,取出移植物;测体积、HE、Masson染色观察病理改变,免疫组织化学法测定组织中HGF表达和血管生成。结果积分吸光度＝100时,Ad—GFP转染MSCs效率可达89．6％;移植后3、5、7、14d,E组移植物中HGF的表达高于其他各组（P〈0．05）;移植后5、7、14、28、60d,E组血管数量也多于其他各组（P〈0．05）;28d和60d时,E组脂肪颗粒体积保持率明显好于其他4组（P〈0．05）。结论携带HGF基因的MSCs在移植物中能够持续表达HGF,有效地减少脂肪颗粒移植后的吸收,从而提高移植颗粒脂肪的存活率。     

影响移植后的脂肪颗粒活性因素

目的观察碱性成纤维细胞生长因子（bFGF）、血管内皮细胞生长因子（VEGF）、表皮细胞生长因子（EGF）、胰岛素及自体真皮颗粒对培养及移植的脂肪颗粒活性的影响因素。方法通过对培养中的幼鼠脂肪细胞,分别添加bFGF、VEGF、EGF、胰岛素及自体真皮颗粒,四甲基偶氮唑盐（MTT）法测定各组脂肪细胞活性,分析其作用效果;通过对移植体的大体观察、质量测定、HE染色、微血管数量及免疫组织化学染色等,比较各组添加物对脂肪组织活性的影响。结果除真皮颗粒组及对照组外,各实验组在不同时间点的最佳脂肪细胞活性浓度基本一致,且其细胞活性均高于对照组（P〈0．05）。动物实验中对照组可见较大区域坏死灶、囊样脂肪池。实验组脂肪细胞大小不一,存在大量的小体积脂肪细胞;除胰岛素组外,各实验组移植物残余质量及各组微血管密度均明显高于对照组,但随移植时间的延长差异逐渐缩小。结论bFGF、VEGF、EGF及胰岛素均能不同程度提高脂肪细胞活性,bFGF、VEGF、EGF及自体真皮颗粒均能不同程度地提高脂肪颗粒移植后的移植物质量,改善脂肪组织的血运重建。     

湿热内蕴型轻度脂肪肝CT定量测定与血脂的相关性研究

目的:依据CT定量测定的结果,分析湿热内蕴型弥漫型轻度脂肪肝的肝脾CT值比值和血脂的变化,初步探讨两者在病程进展中的相关性。方法:60例门诊及住院患者经上腹部CT平扫及中医辨证分型,诊断为湿热内蕴型轻度脂肪肝;分别测量肝、脾CT值,计算肝脾CT值比值;同时检查血脂,包括总胆固醇(TC)、甘油三酯(TG)和高密度脂蛋白胆固醇(HDL-C)。将肝脾CT值的比值分为3个等级,即0.9～1.0(含1.0)、0.8～0.9(含0.9)、0.7～0.8(含0.8),常规统计学描述各等级肝脾CT值的比值及血脂(包括均数、标准差、标准误、95%CI和均数分布图),并进一步行组间方差分析(α=0.05)。结果:3个等级肝脾CT值的比值之间差异有统计学意义(P0.01),3个等级的TC、TG值之间差异无统计学意义;第1等级与第2、3等级的HDL-C值之间差异有统计学意义(P=0.003,P=0.008,P0.01),而第2、3等级之间差异无统计学意义(P=0.936)。结论:①CT定量测定较为准确地反映了肝内脂肪浸润的程度;②湿热内蕴型轻度脂肪肝的肝脾CT值比值在0.9以下时,血清HDL-C含量降低,间接提示肝内脂肪聚集有增加趋势,在临床治疗和随访中对此类患者应予以重视。     

兔延迟术后脂肪瓣内间充质干细胞增殖的实验研究

目的 探讨采用脂肪瓣延迟术等缺血缺氧的方法,促使脂肪来源的兔间充质干细胞(ASCs)增殖的可能性.方法 以兔为动物模型,在一侧腹股沟处形成脂肪瓣.21 d后取出瓣内脂肪组织及对侧正常脂肪组织,消化过筛离心,收集离心后沉淀物中的细胞,用流式细胞仪检测细胞的表面标记,计算细胞CD29、CD44、CD14和CD45的表达率并进行组间比较.结果 脂肪瓣延迟术后,瓣内细胞CD29和CD44的表达率增加,分别为74.06%和90.74%,未经处理的对侧脂肪组织分别为62.88%和77.54%,差异有统计学意义(P<0.05);瓣内细胞CD14和CD45的表达率减少,分别为57.66%和4.84%,未经处理的对侧脂肪组织分别为72.10%和75.82%,差异有统计学意义(P<0.05或P<0.01).结论 脂肪瓣延迟术等缺血缺氧的方法,可促进ASCs的增殖,是用瓣内组织移植后取得更好效果的机制之一;对脂肪组织先进行缺血预处理再移植,可能为一个临床脂肪移植的新方法.