Fucoidan Promotes the Reconstruction of Skin Equivalents

In this study we investigated the effects of fucoidan on the proliferation of fibroblasts and the reconstruction of a skin equivalent (SE). Fucoidan significantly stimulated the proliferation of CCD-25Sk human fibroblasts and Western blot analysis demonstrated that fucoidan markedly increased the expression of cyclin D1 and decreased the expression of p27. Fucoidan was used to reconstruct SE. Immunohistochemical staining showed that the addition of fucoidan to dermal equivalents increased expression of proliferating cell nuclear antigen (PCNA) and p63. In addition, expression of α6-integrin was significantly increased by fucoidan, whereas expression of β1-integrin, type 1 collagen, elastin, fibronectin did not markedly change. These results suggest that fucoidan has positive effects on epidermal reconstruction and will therefore be beneficial in the reconstruction of SE.     

Predicting full thickness skin sensitization using a support vector machine

To assess the public’s propensity for allergic contact dermatitis (ACD), many alternatives to in vivo chemical screening have been developed which generally incorporate a small panel of cell surface and secreted dendritic cell biomarkers. However, given the underlying complexity of ACD, one cell type and limited cellular metrics may be insufficient to predict contact sensitizers accurately. To identify a molecular signature that can further characterize sensitization, we developed a novel system using RealSkin, a full thickness skin equivalent, in co-culture with MUTZ-3 derived Langerhan’s cells. This system was used to distinguish a model moderate pro-hapten isoeugenol (IE) and a model strong pre-hapten p-phenylenediamine (PPD) from irritant, salicylic acid (SA). Commonly evaluated metrics such as CD86, CD54, and IL-8 secretion were assessed, in concert with a 27-cytokine multi-plex screen and a functional chemotaxis assay. Data were analyzed with feature selection methods using ANOVA, hierarchical cluster analysis, and a support vector machine to identify the best molecular signature for sensitization. A panel consisting of IL-12, IL-9, VEGF, and IFN-γ predicted sensitization with over 90% accuracy using this co-culture system analysis. Thus, a multi-metric approach that has the potential to identify a molecular signature may be more predictive of contact sensitization.     

Physical Activity and Risk of Metabolic Phenotypes of Obesity: A Prospective Taiwanese Cohort Study in More Than 200,000 Adults

ObjectiveTo examine the association between physical activity (PA) and the risk for metabolically unhealthy obesity (MUO) or metabolically healthy obesity (MHO) in Asian adults.Patients and MethodsData were obtained from 205,745 healthy individuals 18 years or older. Individuals were classified as inactive, lower or upper insufficiently active, active, and high active. Metabolically unhealthy was defined as having 1 or more of the metabolic syndrome criteria, excluding the abdominal obesity criterion.ResultsThe percentages of metabolically healthy normal-weight (MHNW), metabolically healthy overweight (MHOW), MHO, and MUO in our cohort were 30.8% (63,408 of 205,745), 5.8% (12,002 of 205,745), 4.1% (8329 of 205,745), and 20.7% (42,564 of 205,745), respectively. During a mean follow-up of 6 (range, 0.5-19) years, among 63,408 MHNW participants, 1890 (3.0%) and 1174 (1.9%) developed MUO and MHO, respectively. Among 12,002 MHOW participants, 3404 (28.4%) developed MUO and 2734 (22.8%) developed MHO. A total of 5506 of 8329 (66.1%) participants moved from MHO to MUO, and 5675 of 42,564 (13.3%) moved from MUO to MHO. Compared with being inactive, MHNW individuals who were active or high active showed lower risk for MUO. Among those with MHOW, being high active was associated with reduced risk for MUO and MHO. Although among MHO participants, PA was not associated with incident MUO, being active or high active was linked to a greater likelihood of moving from MUO to MHO.ConclusionPA may prevent the development of both MHO and MUO. PA also helps increase the transition from MUO to MHO, which may contribute to reduce the subsequent development of type 2 diabetes mellitus and major cardiovascular disease complications.     

重混凝土屏蔽质子放疗机房的感生放射性估算

目的 估算肿瘤质子治疗时重混凝土屏蔽墙中铁元素因中子活化产生的感生放射性⁵⁶Mn及其水平。方法 采用Geant4程序构建某质子治疗机房的重混凝土屏蔽墙模型,模拟245 MeV的质子束照射水模体产生的次级中子,统计屏蔽墙内放射性核素⁵⁶Mn的分布。将屏蔽墙按每10 cm厚度分层,计算前3层屏蔽墙中放射性核素⁵⁶Mn产生的周围剂量当量率。结果 在最大的束流照射条件（1.872×10¹⁰个）下,前3层屏蔽墙内的放射性核素⁵⁶Mn个数分别为3.10×10⁸、1.60×10⁸和9.33×10⁸个;对治疗室内1 m远处产生的周围剂量当量率分别为2.13×10^-3、8.82×10^-4 和9.10×10^-4 μSv/h,总的周围剂量当量率为3.92×10^-3 μSv/h。结论 在质子治疗时,距离射束中心轴越近,屏蔽墙的感生放射性越强;屏蔽墙前端中子活化铁元素产生的感生放射性最强,感生放射性随着屏蔽墙厚度增大呈指数形式减小,应主要考虑质子治疗机房屏蔽墙前端产生的感生放射性。     

钳齿形貌对腹腔镜夹钳安全性的影响

目的:对比不同齿形腹腔镜夹钳的夹持效果,以确定其各自安全夹持组织的能力,为夹钳优化设计提供参考。方法:通过ANSYS有限元分析,对比梯形齿、钉形齿、直角楔形齿、等腰楔形齿4种齿形钳头压缩量和牵拉效果关系,并通过应变云图分析夹持能力不同的原因。以钳头夹持组织不损伤、不滑脱为判断标准,评价各齿形夹持能力。结果:直角楔形齿具有最优越的安全夹持能力,钉形齿最容易损伤组织,且其安全牵拉能力最差;梯形齿安全牵拉能力与等腰楔形齿相近,但等腰楔形齿安全压缩量更优。齿数对牵拉效果影响明显。结论:腹腔镜夹钳夹持能力取决于钳齿形貌和齿数,安全夹持性由最大应力和钳制能力共同决定。峰值应力大的齿形并不表示夹持能力强,牵拉能力应考虑钳制变形能力。