Increased risk of atrial fibrillation among elderly Norwegian men with a history of long‐term endurance sport practice

Atrial fibrillation (AF) is the most common cardiac arrhythmia. The prevalence increases with increasing age. In middle‐aged men, endurance sport practice is associated with increased risk of AF but there are few studies among elderly people. The aim of this study was to investigate the role of long‐term endurance sport practice as a risk factor for AF in elderly men. A cross‐sectional study compared 509 men aged 65–90 years who participated in a long‐distance cross‐country ski race with 1768 men aged 65–87 years from the general population. Long‐term endurance sport practice was the main exposure. Self‐reported AF and covariates were assessed by questionnaires. Risk differences (RDs) for AF were estimated by using a linear regression model. After multivariable adjustment, a history of endurance sport practice gave an added risk for AF of 6.0 percent points (pp) (95% confidence interval 0.8–11.1). Light and moderate leisure‐time physical activity during the last 12 months reduced the risk with 3.7 and 4.3 pp, respectively, but the RDs were not statistically significant. This study suggests that elderly men with a history of long‐term endurance sport practice have an increased risk of AF compared with elderly men in the general population.     

Regional variations in intramyocellular lipid concentration correlate with muscle fiber type distribution in rat tibialis anterior muscle.

1H MR spectroscopy (MRS) has proved to be a valuable noninvasive tool to measure intramyocellular lipids (IMCL) in research focused on insulin resistance and type II diabetes in both humans and rodents. An important determinant of IMCL is the muscle fiber type, since oxidative type I fibers can contain up to three times more IMCL than glycolytic type II muscle fibers. Because these different muscle fiber types are inhomogeneously distributed in rodent muscle, in the present study we investigated the distribution of IMCL within the rat tibialis anterior muscle (TA) in vivo using single-voxel 1H MRS along with the muscle fiber distribution in the TA ex vivo determined from immunohistological assays. IMCL levels in the TA differed by up to a factor of 3 depending on the position of the voxel. The distribution of IMCL over the TA cross section was not random, but emerged in a pattern similar to the distribution of the predominantly oxidative muscle fiber types. Dietary interventions, such as high-fat feeding and 15 hr of fasting, did not significantly change this typical fiber type-dependent pattern of IMCL content. These results stress the importance of voxel positioning when single-voxel 1H MRS is used to study IMCL in rodent muscle.     

Evaluation of in-stent stenosis by magnetic resonance phase-velocity mapping in nickel-titanium stents

PURPOSE: To evaluate different grades of in-stent stenosis in a nickel-titanium stent with MRI. MATERIALS AND METHODS: Magnetic resonance phase velocity mapping (MR-PVM) was used to measure flow velocity through a 9-mm NiTi stent with three different degrees of stenosis in a phantom study. The tested stenotic geometries were 1) axisymmetric 75%, 2) axisymmetric 90%, and 3) asymmetric 50%. The MR-PVM data were subsequently compared with the velocities from computational fluid dynamic (CFD) simulations of identical conditions. RESULTS: Good quantitative agreement in velocity distribution for the 50% and 75% stenoses was observed. The agreement was poor for the 90% stenosis, most likely due to turbulence and the high-velocity gradients found in the small luminal area relative to the pixel resolution in our imaging settings. CONCLUSION: The accuracy of the MRI velocities inside the stented area renders MRI a modality that may be used to assess moderate to severe in-stent restenosis (ISR) in medium-sized vascular stents in peripheral vessels, such as the iliac, carotid, and femoral arteries. Advances in MR instrumentation may provide sufficient resolution to obtain adequate velocity information from smaller vessels, such as the coronary arteries, and allow MRI to substitute for invasive and expensive catheterization procedures currently in clinical use.     

Sentinel Lymph Node Detection in Breast Cancer Patients by Real‐Time Virtual Sonography Constructed With Three‐Dimensional Computed Tomography‐Lymphography

Abstract: Ultrasonography (US) is one tool for preoperative diagnosis of lymph node metastases in breast cancer. However, US cannot detect true sentinel lymph nodes (SLNs). We identified SLNs in 60 clinically node‐negative breast cancer patients using a real‐time virtual sonography (RVS) system to display in real time a virtual multi‐planar reconstruction obtained from computed tomography (CT) volume data corresponding to the same cross‐sectional image from US. CT volume data were obtained from our original three‐dimensional CT lymphography (3DCT‐LG), which accurately detects SLNs in breast cancer. SLN metastases were assessed by shape and visibility of the hilum. All patients underwent SLN biopsy and SLN metastases were examined pathologically. In all 60 patients, we were able to detect the same SLNs visualized by 3DCT‐LG. Suspicious SLN metastases were identified in seven of the 60 patients, and four of seven patients were pathologically positive. Positive predictive value was 57%. The remaining 53 patients displayed non‐suspect SLNs in which absence of metastasis from the SLN was confirmed histologically. Overall accuracy was 95%. This is a first attempt at preoperatively identifying SLNs using US guided by the RVS system in breast cancer patients. Although evaluation of SLN metastases was unsatisfactory, this method may be useful for preoperative fine‐needle aspiration cytology for diagnosis of SLN metastases.     

慢性束缚应激对小鼠认知功能及海马不同亚区星形胶质细胞的影响

目的 探讨慢性束缚应激(CRS)对小鼠认知功能的影响,观察海马不同亚区(CA1、CA3和DG区)星形胶质细胞(AS)的激活情况,明确慢性应激对海马的损伤是否存在特异性靶点.方法 雄性KM小鼠24只按体质量随机分为对照组和应激组,每组各12只.采用慢性束缚方法建立小鼠CRS模型,利用新异物体识别实验(NORT)和Morris水迷宫(MWM)评测其认知功能,HE染色观察细胞的形态结构变化,免疫组织化学染色法对海马CA1、CA3和DG区AS标志物胶质纤维酸性蛋白(GFAP)进行染色,采用显微镜和图像分析软件对海马上述亚区AS进行计数并分析GFAP的表达.结果 与对照组相比,应激组小鼠NORT及MWM实验的成绩均显著下降(P＜0.05),海马神经元形态结构损伤,CA1和CA3区AS细胞数及GFAP表达均显著增加(P＜0.05),DG区两者均无显著变化(P＞0.05).结论 CRS能够导致小鼠认知功能障碍,海马CA1、CA3区AS的活化可能是其机制之一.     

Therapeutic Effectiveness of Sustained Low‐Efficiency Hemodialysis Plus Hemoperfusion and Continuous Hemofiltration Plus Hemoperfusion for Acute Severe Organophosphate Poisoning

There is no report on the effects of sustained low‐efficiency dialysis (SLED) plus hemoperfusion (HP) (SLED + HP) in patients with acute severe organophosphate (OP) poisoning (ASOPP). This study was designed to compare the therapeutic effectiveness between SLED + HP and continuous hemofiltration (CHF) plus HP (CHF + HP) in patients with ASOPP. In order to assess the two treatment methods, 56 patients with ASOPP were divided into CHF + HP group and SLED + HP group. The biochemical indicators, in‐hospital duration, hemodynamic parameters, Acute Physiology, and Chronic Health Evaluation (APACHE II) score, and survival and mortality rates were compared. In both groups after treatment, the levels of serum creatine kinase isozyme MB, creatine kinase, creatinine, glutamic‐oxalacetic transaminease, and glutamate‐pyruvate transaminase, and the APACHE II scores on the first, second, and seventh day decreased (P < 0.05), whereas the levels of serum acetylcholinesterase increased. The two groups showed no statistical differences in in‐hospital duration, biochemical indicators, APACHE II score, hemodynamic parameters, survival rate, or the mortality rate (P > 0.05). In conclusion, SLED has similar hemodynamic stability to CHF and the two treatment methods have similar effects on ASOPP patients. More importantly, SLED plus HP is relatively economical and convenient for patients with ASOPP in clinical practice.     

剑花中所含中性洗涤剂纤维对大鼠血清胆固醇的影响

采用动物喂养试验，观察了剑花中所含中性洗涤剂纤维（ＮＤＦ）对大鼠血清胆固醇的影响。结果表明，高脂纤维组大鼠ＴＣ（５８．７１±７．５）明显低于高脂对照组（８１．２６±１８．７７，Ｐ＜０．０１）；两组ＨＤＬ－Ｃ／ＴＣ（０．４１９０±０．０８８６和０．４８７７±０．０９２６）比较无显著性差异（Ｐ＞００５）．提示剑花中ＮＤＦ有效地降低血清总胆固醇，剑花ＮＤＦ对大鼠摄食量及体重的变化无影响。     

肌纤维转化生长因子- β信号激活与急性肌损伤炎症反应的相关性研究

目的:探讨肢体创伤后急性肌损伤炎症反应过程中肌纤维自身转化生长因子- β(TGF- β)信号对肌内炎症的影响。 方法:取野生C57BL/6小鼠（野生小鼠组）、肌纤维条件性TGF- β受体Ⅱ敲除小鼠（敲除小鼠组)各16只。肌毒素腓肠肌内注射诱导小鼠急性肌损伤。比较两组小鼠在注...