Body Fat Assessment Method Using CT Images with Separation Mask Algorithm

In recent years, the number of obese population in Korea has been growing up along with the economic development, environmental factors, and the change in life style. Considering the growth of obese population and the adverse effect of obesity on health, it is getting more important to prevent and diagnose the obesity with the quantitative measurement of body fat that has become an important indicator for obesity. In this study, we proposed a procedure for the automated fat assessment from computed tomography (CT) data using image processing technique. The proposed method was applied to a single-CT image as well as CT-volume data, and results were correlated to those of dual-energy X-ray absorptiometry (DEXA) that is known as the reliable method for evaluating body fat. Using single-CT images, correlation coefficients between DEXA and the automated assessment and DEXA and the manual assessment were 0.038 and 0.058, respectively (P > 0.05). Hence, there was no significant correlation between three methods using the proposed method with single-CT images. On the other hand, in case of CT-volume data, the above correlation coefficients were increased to 0.826, 0.812, and 0.805, respectively (P < 0.01). Thus, DEXA and the proposed methods with CT-volume data showed highly significant correlation with each other. The results suggest that the proposed automated assessment using CT-volume data is a reliable method for the evaluation of body fat. It is expected that the clinical application of the proposed procedure will be helpful to reduce the time for the quantitative evaluation of patient’s body fat.     

Heat transfer to deep tissue: the effect of body fat and heating modality

The purpose of this study was to quantify the thermal transfer characteristics of the skin in relation to body composition as assessed by the ability of water immersion and hot and cold packs with different thicknesses of towels layers to heat or cool deep tissue. Two sets of experiments were conducted to determine the interrelationships between body fat content and muscle temperature after immersion of the limb in water or the application of hot and cold packs. In the first series of experiments, subjects immersed their lower body in water at 42, 37, 34, 27, 24 and 0 °C for 20 minutes. Muscle temperature was measured in the skin above and in the belly of the quadriceps and medial gastrocnemius muscles by a thermistor on the skin and one implanted with a 20-gauge needle 25 mm below and perpendicular to the skin. To see the effect of circulation, a series was conducted with the circulation occluded. In the second series, hot or cold packs were used with different thicknesses of towel layers. The muscle temperature after immersion in water approached that of the packs within approximately 20 minutes. In contrast, when hot and cold packs were used with various thickness or towels ranging from 2 to 10 mm in thickness, the change in muscle temperature was much less and it was still changing at the end of a 20 minute period. Subjects with high body fat changed their deep tissue temperatures much more slowly with a time constant nearly double that of the thin subjects with all modalities. Even after water immersion, if the body fat exceeded 25% of the subject's weight, 20 min of immersion was not enough to either warm the muscle or cool it down substantially. Cold packs and hot packs were very ineffective in changing muscle temperature under these same conditions. Body fat plays a major role, as did limb blood flow in controlling the movement of heat across the limb.     

Use of a lipid emulsion in a patient with refractory hypotension caused by glyphosate-surfactant herbicide

Context. Circulatory shock is a major cause of mortality in glyphosate-surfactant herbicide (GlySH) poisoning, and this condition responds poorly to conventional therapies. We report a case of GlySH poisoning with shock that was refractory to vasopressors but responsive to intravenous fat emulsion (IFE). Case details.?A 52-year-old man was brought to the emergency department by ambulance. He was found unconscious in his living room along with an empty bottle of GlySH herbicide, which contained glyphosate, polyoxyethyleneamine (POEA) surfactant, and water. He was drowsy at presentation. His heart rate was 44 beats/min, his blood pressure could not be measured with an arm cuff, but he had a palpable femoral pulse. After about 2.5 h of supportive care after admission, he remained hypotensive, and his systolic blood pressure was 80 mmHg. A 500 mL bottle of 20% IFE product was prepared. As a bolus, 100 mL of IFE was injected, and the remaining 400 mL was then infused. His blood pressure was 100/60 mmHg 1 h after the bolus injection. At 5 h after IFE injection, his blood pressure reached 160/100 mmHg and vasopressors were tapered. Conclusion.?IFE should be considered in cases of refractory hemodynamic instability caused by GlySH after aggressive fluid and vasopressor support.     

富血小板纤维蛋白修复大鼠骨外露创面的实验研究

目的探讨富血小板纤维蛋白(PRF)治疗大鼠骨外露创面的疗效。方法取10~12周龄,250~300 g的雄性SD大鼠24只,应用随机数字表法将其分为3组,每组8只。将所有SD大鼠前头盖骨区域1.5 cm×1.5 cm皮肤全层切除及并去除颅骨表面的骨膜。PRF组创面覆盖PRF;脂肪移植组创面覆盖等量脂肪颗粒;对照组创面覆盖等量生理盐水。分别于第4、7和11天对创面换药。使用Image J软件对骨外露面积进行量化评估。应用HE染色和马松三色染色评估创面新生血管和胶原沉积情况。酶联免疫吸附实验检测创面肉芽组织生长因子水平。组间比较采用随机资料单因素方差分析。结果术后第4天时,PRF组大鼠骨外露比例为57.99%±11.29%;脂肪移植组骨外露比例为45.92%±9.55%;对照组骨外露比例为77.73%±5.57%。第7天时,PRF组大鼠骨外露比例为4.29%±2.28%;脂肪移植组骨外露比例为29.52%±6.33%;对照组骨外露比例为36.90%±8.43%。第11天时,仅PRF组的骨外露创面完全被肉芽组织覆盖,脂肪移植组及对照组均存在不同程度的骨外露,分别为10.15%±1.49%和21.69%±2.40%。PRF组在各时间点创面骨外露面积均显著低于对照组,差异具有统计学意义(P<0.01)。在第7天和第11天时,PRF组的骨外露比例显著低于脂肪移植组,但是在第4天时,脂肪移植组的骨外露比例却低于PRF组,差异均具有统计学意义(P<0.001)。第11天时,HE染色结果显示PRF组的新生微血管密度为(10.37%±0.49%)显著高于脂肪移植组(4.86%±0.83%)和对照组(2.91%±0.31%)(P<0.05),马松三色染色结果显示PRF组的胶原纤维最丰富。酶联免疫吸附实验结果提示第11天时PRF组的生长因子水平均明显升高,与脂肪移植组和对照组比较,差异均具有统计学意义(P<0.05)。结论PRF作为一种取材方便的治疗手段,对修复创面具有良好的疗效,可加快骨外露创面愈合。     

The adipogenic potential of various extracellular matrices under the influence of an angiogenic growth factor combination in a mouse tissue engineering chamber

The extracellular matrix (ECM) Matrigel™ has frequently and successfully been used to generate new adipose tissue experimentally, but is unsuitable for human application. This study sought to compare the adipogenic potential of a number of alternative, biologically derived or synthetic ECMs with potential for human application, with and without growth factors and a small fat autograft. Eight groups, with six severe combined immunodeficient (SCID) mice per group, were created with bilateral chambers (silicone tubes) implanted around the epigastric vascular pedicle, with one chamber/animal containing a 5 mg fat autograft. Two animal groups were created for each of four ECMs (Matrigel™, Myogel, Cymetra® and PuraMatrix™) which filled the bilateral chambers. One group/ECM had no growth factors added to chambers whilst the other group had growth factors (GFs) (vascular endothelial growth factor-A (VEGF-A) plus fibroblast growth factor-2 (FGF-2) plus platelet-derived growth factor-BB (PDGF-BB)) added to both chambers. At 6 weeks, chamber tissue was morphometrically assessed for percent and absolute adipose tissue volume. Overall, the triple GF regime significantly increased percent¹ and absolute^# adipose tissue volume (p < 0.0005^1#) compared to chambers without triple GF treatment. The fat autograft also significantly increased percent (p < 0.0005) and absolute (p < 0.011) adipose tissue volume. Cymetra® (human collagen) constructs yielded the largest total tissue and absolute adipose tissue volume. We found that the pro-angiogenic FGF-2, VEGF-A and PDGF-BB combination in ECMs of synthetic and biological origin produced an overall significantly increased adipose tissue volume at 6 weeks and may have clinical application, particularly with Cymetra.