磁共振波谱成像评估初发2型糖尿病患者骨髓脂肪含量

目的探讨磁共振波谱成像(MRS)定量评估初发2型糖尿病(T2DM)骨髓脂肪含量变化及其与胰岛素抵抗的相关性。方法初发T2DM患者及年龄匹配的正常对照组(n=32/组)行双能X线骨密度测定及股骨颈MRS扫描,分别获得骨密度(BMD)及骨髓脂肪分数(FF)。检查2组研究对象空腹血糖(FPG)、糖化血红蛋白(Hb A1c)、胰岛素(FINS)及血脂指标(TC、TG、HDL-C、LDL-C),利用稳态模式评估法评价胰岛素抵抗(HOMA-IR)。结果初发T2DM组BMD值与对照组无统计学差异。初发T2DM组FF值显著高于正常对照组(P0.001),校正糖代谢、脂代谢及BMD值,2组间FF值仍存在统计学差异(F值=16.763,P=0.012)。FF与HOMA-IR呈中度正相关性(r=0.683,P0.001),校正BMI,FF与HOMA-IR仍然存在正相关性(r=0.592,P=0.018)。结论初发T2DM患者骨髓脂肪增高,骨髓脂肪增多可能是胰岛素抵抗的影响因素之一。     

~1H-MRS评价绝经后2型糖尿病患者腰椎骨髓脂质变化

目的利用轻质子磁共振波谱技术(1 H-MRS)评价绝经后2型糖尿病(T2DM)腰椎骨髓脂质含量(MLC)变化规律。方法收集绝经后T2DM患者(n=30)及年龄匹配的健康受试者(n=20)行L3椎体1 H-MRS扫描以计算MLC值及双能X线骨密度测定仪测定L1~L4椎体骨密度(BMD)。测定受检者空腹血糖(FPG)、糖化血红蛋白(HbA1c)及胰岛素(FINS)水平。结果 T2DM组BMD(1.180±0.198)g/cm2与健康对照组BMD(1.113±0.187)g/cm2无统计学差异。T2DM组MLC(76.3±18.3)%明显高于正常受试者(65.7±14.0)%(P0.001),校正受试者T2DM病程、体质分数、FINS及BMD混杂因素,T2DM组MLC值仍高于健康受试者(P=0.020)。Logistic逐步回归分析表明,MLC是T2DM患者的负性影响因素(OR=2.031,P=0.008)。结论绝经后T2DM患者骨髓脂肪增高,1 H-MRS测定MLC可作为T2DM随诊方法之一。     

MRS评估骨关节炎患者骨髓脂肪含量的变化

目的探讨氢质子磁共振波谱成像(MRS)评估绝经后女性髋部骨关节炎(OA)患者骨髓脂肪分数(FF)的变化。方法收集绝经后髋部骨关节炎患者(n=31)及健康对照组(n=22)行腰3椎体MRS检查及骨密度测定,计算骨髓FF。测定骨代谢标记物总I型前胶原氨基端肽(PINP)及骨吸收标志物I型胶原羧基端肽β(β-CTX)。结果 OA患者骨密度、PINP及β-CTX均高于正常对照组,差异有统计学意义。OA患者骨髓FF(58.5%±6.3%)较正常对照组(50.2%±5.2%)增高14.2%(t=2.411,P0.001),校正骨密度值,组间骨髓FF仍存在统计学差异。OA组及健康对照组骨髓FF均与骨密度(r分别为-0.532、-0.497,P均0.001)存在负相关性,但与PINP及β-CTX无线性相关性。结论绝经后髋部OA骨量虽然并未明显下降,但OA存在骨髓脂肪增多,提示OA存在骨脆性增高。     

~1H-MRS与DWI在骨质疏松症中的初步应用

目的 探讨绝经后女性腰椎骨髓脂肪分数(fat fraction,FF)、表观扩散系数(apparent diffusion coefficient,ADC)值与骨密度(bone mineral densities,BMD)的关系.资料与方法 将行腰椎双能量X线吸收测定(dual X-rayabsorptionmetry,DXA)的60例绝经后女性根据T值分为3组:骨质正常组(T>-1.0)20例,骨质减少组(T=-1.0～-2.5)20例,骨质疏松组(T<-2.5)20例.所有研究对象均行氢质子磁共振波谱分析(~1H MR spectroscopy,~1H-MRS)、MR扩散加权成像(diffusion weighted imaging,DWI),分别测定L_3椎体FF和ADC值.采用组间t检验对不同骨质组间FF、ADC值差异进行统计学分析.采用Pearson相关分析3组间FF、ADC值与BMD的相关性. 结果骨质疏松组脂肪含量[(59.1±8.8)%,P=0.003]与骨质减少组脂肪含量[(54±7.6)%,P=0.039]均比骨质正常组[(49±9.1)%]高.骨质疏松组比骨质减少组椎体脂肪含量高(P=0.045).椎体骨髓ADC值与T值无相关性.所有绝经后女性患者FF值与T值呈负相关(r=-0.46,P<0.01),与ADC值间呈轻度负相关(r=-0.25,P<0.05),但骨质疏松组中FF值与ADC值间呈较明显负相关(r=-0.72,P<0.01).ADC值与T值无相关性(r=0.315,P>0.05).结论 绝经女性椎体骨髓脂肪含量随着BMD的减小而增大.MRS可作为BMD检查的辅助手段.MRS与DWI可以无创性了解骨质疏松症患者骨髓的生理、病理变化,单纯DWI并不能反映BMD的改变.     

磁共振波谱成像评价绝经前双侧卵巢切除术对骨髓脂肪的影响

目的探讨磁共振波谱成像(MRS)评估绝经前双侧卵巢切除术对腰椎骨髓脂肪的影响。方法收集32例接受子宫切除术和双侧卵巢切除术的患者(年龄47.4±2.8岁),分别在术前、术后第6个月、12个月行腰3椎体MRS扫描,测定骨髓脂肪分数(fat fraction,FF)。同时,定量CT测量L 3椎体松质骨容积骨密度(vBMD)。结果卵巢切除术后,腰椎vBMD呈现时序性降低而骨髓FF呈现急剧时序性增高。术后6个月骨髓FF及腰椎vBMD分别为(49.7±6.9)%、(134±22)mg/cc,FF急剧增加22.7%,而vBMD下降9.5%。术后12个月时骨髓FF及腰椎vBMD分别为(53.1±6.3)%、(128±24)mg/cc,分别较6个月时增高6.8%、降低4.5%。相关性分析示△vBMD6M-0M与△FF6M-0M(r=-0.801,P<0.001)、△vBMD12M-0M与△FF12M-0M(r=-0.769,P<0.001)以及△vBMD12M-6M与△FF12M-6M(r=-0.680,P<0.001)均存在负相关性。结论双侧卵巢切除术导致骨髓脂肪含量急剧增加,骨小梁密度减少。MRS测定卵巢切除术后骨髓脂肪或许可早于BMD探及骨髓分子生化成分变化。     

化学位移成像及MR波谱分析在体外水脂模型中对脂肪定量的研究

目的 评价化学位移成像(chemical shift imaging,CSI)和MRS两种方法在脂肪研究中的作用,为进一步活体实验提供定量标准.方法 在7.0 T MR成像仪上运用CSI和MRS方法对体外水脂模型进行水脂定量分析.体外水脂模型的脂肪含量从0～100%平均分成11个组,各组间浓度相差10%,分别应用水、脂肪选择性CSI和1H-MRS对体外水脂模型进行图像和波谱数据采集,对2种方法所得结果分别与实际水脂含量进行单样本t检验及相关分析并比较两种方法问的相关性.MRS计算100%油模型饱和脂肪酸(fraction of saturated fatty acids,FS)、不饱和脂肪酸(fraction of unsaturated fatty acids,FU)的相对含量及多聚不饱和程度(polyunsaturation degree,PUD).结果 CSI法测定实际脂肪含量为50%～100%的测量值分别为(48.0±1.0)%、(57.0±0.5)%、(67.3±0.6)%、(77.3 ±0.6)%、(83.3±0.6)%和(91.0±1.0)%;MRS测定实际脂肪含量为10%～60%的测量值分别为(8.3±0.6)%、(16.3±0.7)%、(27.7±0.6)%、(36.0±1.0)%、(43.5±0.6)%和(56.5±1.0)%,均轻度低估了脂肪含量,差异均有统计学意义(P值均<0.05).CSI与MRS计算的脂肪含量与实际脂肪含量间均呈线性相关(CSI:r=0.998,MRS:r=0.996;P值均<0.01);两种方法间也呈线性相关(r=0.992,P<0.01),两种方法定量脂肪含量差异无统计学意义(t=-0.125,P:0.903).MRS计算橄榄油的FS和FU相对含量分别为0.15和0.85,PUD为0.0325,与实际含量一致.结论 在7.0 T MR成像仪上,体外水脂模型证实CSI和MRS定量脂肪的准确性及在脂肪研究上的可行性.     

2型糖尿病患者大脑后扣带回谷氨酸代谢的磁共振波谱研究

目的 探讨2型糖尿病(T2DM)患者大脑后扣带回谷氨酸代谢变化及其与血糖的关系,以了解糖尿病脑病病理生理变化的物质基础.方法 连续收集15例T2DM患者和10例健康志愿者,采用TE-averaged PRESS序列行MRS检查,比较2组间大脑后扣带回谷氨酸(Glu)、N-乙酰天门冬氨酸(NAA)、乙酰胆碱(Cho)和肌酸(Cr)水平差异,分析代谢物与血糖水平之间的关系.结果 与对照组相比,T2DM组大脑后扣带回Cho (P=0.02)及Glu (P＜0.01)含量显著升高,NAA含量显著降低(P=0.03),而Cr在2组间无显著差异(P＞0.05).在对照组和T2DM组,糖化血红蛋白(HbA1c)与Glu之间呈显著正相关(r=0.692,P=0.000),而糖化血红蛋白与NAA呈显著的负相关(r=-0.628,P=0.001).结论 采用TE-averaged PRESS序列可测定T2DM患者大脑后扣带回脑区代谢物水平的变化,尤其是可以独立测量Glu含量,并发现Glu升高和NAA下降与高血糖有关.     

绝经后女性腰椎骨髓脂肪含量与腹内脂肪组分相关性研究

目的探讨绝经后妇女骨髓脂肪含量与内脏脂肪(VAT)、皮下脂肪组织(SAT)及其比值的相关性。方法绝经后健康女性受试者37例(年龄50~68岁)行L3椎体单体素磁共振波谱扫描获得椎体骨髓脂肪分数(FF),腹部(以L4为水平)横断位T1WI成像以定量VAT及SAT,并计算VAT/SAT。评价MRI两次重复扫描可重复性及不同观察者测量值的一致性,多元回归分析FF值的独立相关因素。结果 L3椎体FF值测量可重复性变异系数(CV)为2.86%,而SAT及VAT CV分别为1.45%、2.29%。不同观察者间测量SAT及VAT组内相关系数分别为0.962、0.935(P均0.001)。FF值与VAT(r=0.598)、SAT(r=-309)、VAT/SAT比值(r=492)、年龄(r=0.327)、绝经年数(r=0.401)、BMI(r=-0.332)存在一定相关性(P均0.05)。多元线性回归分析显示VAT(Sβ=0.417,P0.001)及VAT/SAT(Sβ=0.398,P=0.009)是FF值的独立负性相关因素。结论绝经后女性骨髓脂肪含量与内脏脂肪组织有关。     

T2*校正水脂分离MRI评价慢性肾脏病非透析患者骨髓脂肪含量变化

目的 探讨T2*校正水脂分离序列定量慢性肾脏病(CKD)非透析患者腰椎骨髓脂肪分数(MFF)及其与骨代谢指标的相关性.方法 78例CKD患者按肾小球滤过率(eGFR)分为5组,所有患者行T2*校正3D VIBE水脂分离扫描,计算MFF并评价2次重复扫描的精确性及不同观察者测量MFF的一致性.检测血钙、磷、碱性磷酸酶、骨钙素、甲状旁腺素及25(OH)D3.结果 MRI重复扫描MFF变异系数为2.37％,观察者间测定MFF组内相关系数(ICC)为0.901,2位观察者内ICC分别为0.959、0.948.MFF在各期CKD中均存在统计学差异,与血钙、磷、甲状旁腺素、碱性磷酸酶及骨钙素比较,MFF值变化出现较早.MFF与血磷(r=3.011,P=0.003)、甲状旁腺素水平(r=3.852,P＜0.001)呈正相关性,与血钙(r=-2.767,P=0.017)、25(OH)D3(r=-6.032,P＜0.001)、eGFR(r=-5.104,P＜0.001)呈负相关性.多元线性回归分析,25(OH)D3 (Sβ=-0.343)及eGFR(Sβ=-0.284,P均＜0.001)是MFF的独立影响因素.结论 CKD非透析患者存在骨髓脂肪浸润,T2*校正水脂分离MRI是定量CKD骨髓脂肪含量的有效手段.     

2型糖尿病病人脑白质高信号与情景记忆的相关性研究

目的探讨2型糖尿病(T2DM)病人脑白质高信号(WMH)与情景记忆的相关性。方法前瞻性收集T2DM病人132例[男56例,女76例,平均年龄(58.5±7.0)岁],无糖尿病对照120例[男43例,女77例,平均年龄(57.4±7.3)岁],均行MR数据采集和量表测试。采用改良Scheltens半定量评分法对脑深部WMH(dWMH)及脑室旁WMH(pvWMH)进行评分。采用独立样本t检验或Mann-Whitney U检验比较2组WMH评分、空腹血糖(FBG)、糖化血红蛋白(HbA1c)、Rey-Osterrieth复杂图形测验(ROCF)及Rey听觉词语学习测试(RAVLT)的差异,采用卡方检验比较2组间计数资料。采用Kappa检验分析2名医师间WMH评分的一致性。采用偏相关分析方法检测T2DM病人的WMH评分与ROCF及RAVLT评分的相关性。结果与对照组相比,T2DM组的FBG和HbA1c增高(P0.05),T2DM组RAVLT及ROCF评分均降低(P0.05);其余参数比较,其差异均无统计学意义(P0.05)。T2DM组dWMH评分与ROCF延迟回忆评分呈负相关(r=-0.204,P=0.021)。结论 T2DM病人情景记忆能力下降,并与WMH有关。WMH可能是识别T2DM病人情景记忆能力下降的影像标志物。     

Does vertebral bone marrow fat content correlate with abdominal adipose tissue,lumbar spine bone mineral density,and blood biomarkers in women with type 2 diabetes mellitus?

Purpose:

To compare vertebral bone marrow fat content quantified with proton MR spectroscopy (¹H‐MRS) with the volume of abdominal adipose tissue, lumbar spine volumetric bone mineral density (vBMD), and blood biomarkers in postmenopausal women with and without type 2 diabetes mellitus (T2DM).

Materials and Methods:

Thirteen postmenopausal women with T2DM and 13 age‐ and body mass index‐matched healthy controls were included in this study. All subjects underwent ¹H‐MRS of L1–L3 to quantify vertebral bone marrow fat content (FC) and unsaturated lipid fraction (ULF). Quantitative computed tomography (QCT) was performed to assess vBMD of L1–L3. The volumes of abdominal subcutaneous/visceral/total adipose tissue were determined from the QCT images and adjusted for abdominal body volume (SAT_adj/VAT_adj/TAT_adj). Fasting blood tests included plasma glucose and HbA1c.

Results:

Mean FC showed an inverse correlation with vBMD (r = ?0.452; P < 0.05) in the whole study population. While mean FC was similar in the diabetic women and healthy controls (69.3 ± 7.5% versus 67.5 ± 6.1%; P > 0.05), mean ULF was significantly lower in the diabetic group (6.7 ± 1.0% versus 7.9 ± 1.6%; P < 0.05). SAT_adj and TAT_adj correlated significantly with mean FC in the whole study population (r = 0.538 and r = 0.466; P < 0.05). In contrast to the control group, significant correlations of mean FC with VAT_adj and HbA1c were observed in the diabetic group (r = 0.642 and r = 0.825; P < 0.05).

Conclusion:

This study demonstrated that vertebral bone marrow fat content correlates significantly with SAT_adj, TAT_adj, and lumbar spine vBMD in postmenopausal women with and without T2DM, but with VAT_adj and HbA1c only in women with T2DM. J. Magn. Reson. Imaging 2012;35:117‐124. © 2011 Wiley Periodicals, Inc.

     

Quantification of hepatic steatosis with MRI: The effects of accurate fat spectral modeling

Purpose

To develop a chemical‐shift–based imaging method for fat quantification that accounts for the complex spectrum of fat, and to compare this method with MR spectroscopy (MRS). Quantitative noninvasive biomarkers of hepatic steatosis are urgently needed for the diagnosis and management of nonalcoholic fatty liver disease (NAFLD).

Materials and Methods

Hepatic steatosis was measured with “fat‐fraction” images in 31 patients using a multiecho chemical‐shift–based water‐fat separation method at 1.5T. Fat‐fraction images were reconstructed using a conventional signal model that considers fat as a single peak at –210 Hz relative to water (“single peak” reconstruction). Fat‐fraction images were also reconstructed from the same source images using two methods that account for the complex spectrum of fat; precalibrated and self‐calibrated “multipeak” reconstruction. Single‐voxel MRS that was coregistered with imaging was performed for comparison.

Results

Imaging and MRS demonstrated excellent correlation with single peak reconstruction (r² = 0.91), precalibrated multipeak reconstruction (r² = 0.94), and self‐calibrated multipeak reconstruction (r² = 0.91). However, precalibrated multipeak reconstruction demonstrated the best agreement with MRS, with a slope statistically equivalent to 1 (0.96 ± 0.04; P = 0.4), compared to self‐calibrated multipeak reconstruction (0.83 ± 0.05, P = 0.001) and single‐peak reconstruction (0.67 ± 0.04, P < 0.001).

Conclusion

Accurate spectral modeling is necessary for accurate quantification of hepatic steatosis with MRI. J. Magn. Reson. Imaging 2009;29:1332–1339. © 2009 Wiley‐Liss, Inc.     

2型糖尿病血糖控制水平与并发心血管疾病的风险研究

目的：探讨2型糖尿病（T2DM）患者血糖控制水平与并发心血管疾病风险的关系。方法：根据糖化血红蛋白（HbA1C）的含量将T2DM患者分成血糖控制良好组（HbA1C≤6.5%,n=62）和血糖控制不佳组（HbA1C〉6.5%,n=41）,分别对其脂蛋白（a）[LP（a）]、同型半胱氨酸（Hcy）、超敏C反应蛋白（hs-CRP）以及常规血脂项目进行检测。结果：血糖控制不佳组,其血清低密度脂蛋白胆固醇（LDL-C）、LP（a）、hs-CRP、Hcy均高于血糖控制良好组（P〈0.01或P〈0.05）,而高密度脂蛋白胆固醇（HDL-C）明显低于血糖控制良好组（P〈0.01）。结论：T2DM患者HbA1C水平越高,血糖控制越差,并发心血管疾病的风险就越高,因此,控制好血糖对预防或延缓T2DM患者并发心血管疾病具有重要意义。     

2型糖尿病患者合并脑梗死的相关危险因素分析

目的探讨2型糖尿病患者合并脑梗死的危险因素。方法收集448例2型糖尿病患者的临床资料,根据是否合并脑梗死将患者分为糖尿病脑梗死组和糖尿病非脑梗死组,比较可能诱发脑梗死的危险因素。结果 81例患者合并脑梗死占总数的18.1%。脑梗死组与非脑梗死组比较,年龄[(70.53±7.79)岁与(60.72±13.03)岁]、糖尿病病程[(130.25±85.77)月与(94.54±92.41)月]、踝肱指数[(0.90±0.23)与(0.98±0.19)]、尿素氮[(6.84±2.49)mmol/L与(6.17±2.21)mmol/L]、糖化血红蛋白[(9.09%±2.41)%与(8.24±1.77)%]及高血压(84.0%与59.1%)、冠心病(63.0%与43.1%)、糖尿病视网膜病变(35.8%与22.6%)、糖尿病肾病(50.6%与31.9%)、下肢动脉斑块(87.7%与70.3%)的合并率两组之间的差异均有统计学意义(P<0.05)。Logistic回归显示年龄(P=0.000)、糖化血红蛋白(P=0.027)与脑梗死的发生密切相关。结论年龄、糖化血红蛋白升高为影响2型糖尿病脑梗死的主要危险因素,积极控制血糖可减少脑梗死的发生。     

肥胖合并2型糖尿病患者胃旁路手术后相关指标的变化

 目的 探讨肥胖合并2型糖尿病患者腹腔镜胃旁路手术(LRYGB)后相关指标的变化。方法 回顾性分析2011-03至2012-02在原武警总医院普外科接受LRYGB的52例肥胖合并2型糖尿病患者的临床资料,分别在术前、术后3、6、12个月,采用人体成分分析仪检测全身脂肪总量和非脂肪总量变化,通过日本东芝公司80排螺旋CT+美国明维思公司校准体模和定量CT(QCT)分析软件,记录腹部总体脂肪体积(TAFV)、腹部内脏脂肪总体积(TVFV)和腹部皮下脂肪总体积(TSFV)的变化;同时测定相应时间点血清瘦素、脂联素(APN)及糖脂代谢指标,部分指标随访5年。结果 (1)术后12个月糖尿病达标率为86.5%,肥胖症治愈率为67.3%,术后各时间点空腹胰岛素(Fins)和HOMA-IR数值呈逐渐下降趋势,仅在术后12个月和术后5年明显下降,差异有统计学意义(P＜0.05)。与术前相比,在术后12个月三酰甘油(TG)、胆固醇(CH)下降明显,差异均有统计学意义(P＜0.05),术后5年TG略有升高,但与术前差异仍有统计学意义(P＜0.05)。(2)与术前相比,术后6、12个月和2年瘦素下降明显,差异均有统计学意义(P＜0.05);术后APN在术后3个月略有下降,然后呈逐渐升高趋势,在术后12个月和2年APN数值显著升高,差异均有统计学意义(P＜0.05)。(3)术后各时间点体重和BMI均呈下降趋势,术后5年下降明显,与术前比较,差异有统计学意义(P＜0.05)。术后非脂肪总量有下降趋势,但仅在术后5年时变化明显。与术前相比,术后6个月TVFV显著下降,术后12个月TSFV显著下降,术后5年TSFV和TVFV均显著下降,差异有统计学意义(P＜0.05)。结论 LRYGB术后腹部内脏脂肪较皮下脂肪减少更为显著,伴血清瘦素降低和APN增高。     

胰岛素治疗后糖尿病患者抑郁情绪变化与皮质醇水平的关系

目的观察胰岛素强化治疗前后糖尿病抑郁患者的情绪变化及与血清皮质醇水平的相关性。方法选择340例2型糖尿病(T2DM)患者,其中187例给予胰岛素强化治疗3个月,153例给予口服降糖药治疗,对入选患者治疗前后进行抑郁测定以及血糖、糖化血红蛋白(HbA1c)、血清皮质醇检测,并进行统计学处理。治疗期间空腹血糖控制在4.4～6.1 mmol/L,餐后2h血糖控制在4.4～8.0 mmol/L之间。结果胰岛素治疗前合并抑郁情绪及无抑郁情绪的糖尿病患者皮质醇水平分别为:(276.1±23.4)、(141.1±19.9)μg/L(P<0.01);胰岛素治疗后合并抑郁患者抑郁指数较治疗前明显降低,分别为(0.51±0.13)、(0.68±0.21)(P<0.01),皮质醇水平明显降低为(162.4±17.3)μg/L(P<0.01)。治疗前抑郁指数与皮质醇呈显著正相关(r=0.674,P<0.01);胰岛素组治疗后抑郁指数下降与皮质醇下降呈正相关(r=0.525,P<0.05)。而口服降糖药组治疗前后抑郁指数及皮质醇水平无明显变化。结论胰岛素治疗后T2DM患者抑郁情绪的改善与皮质醇水平相关。     

Body composition analysis of obesity and hepatic steatosis in mice by relaxation compensated fat fraction (RCFF) MRI

Purpose:

To develop and validate a quantitative magnetic resonance imaging (MRI) methodology for phenotyping animal models of obesity and fatty liver disease on 7T small animal MRI scanners.

Materials and Methods:

A new MRI acquisition and image analysis technique, relaxation‐compensated fat fraction (RCFF), was developed and validated by both magnetic resonance spectroscopy and histology. This new RCFF technique was then used to assess lipid biodistribution in two groups of mice on either a high‐fat (HFD) or low‐fat (LFD) diet.

Results:

RCFF demonstrated excellent correlation in phantom studies (R² = 0.99) and in vivo compared to histological evaluation of hepatic triglycerides (R² = 0.90). RCFF images provided robust fat fraction maps with consistent adipose tissue values (82% ± 3%). HFD mice exhibited significant increases in peritoneal and subcutaneous adipose tissue volumes in comparison to LFD controls (peritoneal: 6.4 ± 0.4 cm³ vs. 0.7 ± 0.2, P < 0.001; subcutaneous: 14.7 ± 2.0 cm³ vs. 1.2 ± 0.3 cm³, P < 0.001). Hepatic fat fractions were also significantly different between HFD and LFD mice (3.1% ± 1.7% LFD vs. 27.2% ± 5.4% HFD, P = 0.002).

Conclusion:

RCFF can be used to quantitatively assess adipose tissue volumes and hepatic fat fractions in rodent models at 7T. J. Magn. Reson. Imaging 2012;35:837–843. © 2011 Wiley Periodicals, Inc.     

The effect of rowing on endothelial function and insulin action in healthy controls and in patients with type 2 diabetes

Patients with type 2 diabetes (T2DM) have an increased risk for cardiovascular disease. We examined the effects of 8 weeks of home‐based rowing training (heart rate corresponding to 65–70% of VO_{2 peak}) on endothelial function and glucose clearance (local and systemic effects) in male subjects with T2DM (n=9) and matched controls (n=8). Before and after training (30 min every other day), all subjects underwent sequential graded brachial artery infusions of non‐insulin vasodilators (acetylcholine; sodium nitroprusside; adenosine). Forearm blood flow was improved by training in controls (without and with insulin: P=0.003 and 0.05, respectively) but not in subjects with T2DM. Likewise, whole body glucose clearance increased in response to training in controls (P=0.05) but not in T2DM. However, in both groups, the capacity for local forearm glucose extraction (controls: P=0.001; T2DM: P=0.002) and clearance (controls: P<0.001; T2DM: P=0.01) were positively affected by exercise. While the subjects with T2DM did not respond to the same degree as controls to 8 weeks of home‐based exercise, there are clear benefits as illustrated by improvements in local glucose disposal. Training of higher intensity or duration may be required in order to elicit a response similar to controls.     

2型糖尿病患者心外膜脂肪组织厚度与主动脉传播速度和颈动脉内-中膜厚度的相关性

 目的 探讨2型糖尿病(type 2 diabetes mellitus,T2DM)患者心外膜脂肪厚度(epicardial fat thickness,EFT)、主动脉传播速度(aortic velocity propagation,AVP)和颈动脉内-中膜厚度(carotid intima-media thickness,CIMT)之间的关联性。方法 选取2019-11至2020-06武警特色医学中心内分泌与血液科住院的年龄＞18岁未明确诊断冠心病的T2DM患者41例(T2DM组),同时选择37例非糖尿病患者(对照组),所有受试者均采用超声心动图测定EFT和AVP,用超声检查结果计算CIMT。结果 T2DM组EFT[(8.41±1.62)mm]、CIMT[ (0.93±0.21)mm]显著高于对照组[(6.32±2.19)mm、(0.53±0.11)mm],AVP[(28.21±16.03)mm)]显著低于对照组[(58.12±17.49)mm],差异均有统计学意义(P<0.05)。相关性分析显示, EFT和AVP呈显著负相关(r=-0.339,P=0.001),EFT与CIMT呈显著正相关(r=0.415,P<0.001),AVP与CIMT呈显著负相关(r=-0.629,P<0.001)。逐步线性回归分析显示,CIMT是EFT(β₁=3.255,95%CI:1.775~4.739,P=0.001)、AVP的独立预测因子(β₂=-30.868,95%CI:-45.805~-15.932,P<0.001)。ROC曲线分析显示,EFT 7.2 mm、CIMT 0.66 mm分别被确定为T2DM亚临床动脉粥样硬化的有效分界点,敏感性分别为75.8%和92.5%,特异性分别为71.1%和78.2%。结论 T2DM患者EFT、CIMT升高,AVP降低,且EFT、AVP分别与CIMT显著相关,EFT、CIMT可以作为评估T2DM患者亚临床动脉粥样硬化的可靠指标。