Amoeboid organism solves complex nutritional challenges

A fundamental question in nutritional biology is how distributed systems maintain an optimal supply of multiple nutrients essential for life and reproduction. In the case of animals, the nutritional requirements of the cells within the body are coordinated by the brain in neural and chemical dialogue with sensory systems and peripheral organs. At the level of an insect society, the requirements for the entire colony are met by the foraging efforts of a minority of workers responding to cues emanating from the brood. Both examples involve components specialized to deal with nutrient supply and demand (brains and peripheral organs, foragers and brood). However, some of the most species-rich, largest, and ecologically significant heterotrophic organisms on earth, such as the vast mycelial networks of fungi, comprise distributed networks without specialized centers: How do these organisms coordinate the search for multiple nutrients? We address this question in the acellular slime mold Physarum polycephalum and show that this extraordinary organism can make complex nutritional decisions, despite lacking a coordination center and comprising only a single vast multinucleate cell. We show that a single slime mold is able to grow to contact patches of different nutrient quality in the precise proportions necessary to compose an optimal diet. That such organisms have the capacity to maintain the balance of carbon- and nitrogen-based nutrients by selective foraging has considerable implications not only for our understanding of nutrient balancing in distributed systems but for the functional ecology of soils, nutrient cycling, and carbon sequestration.     

无细胞真皮基质在特重烧伤晚期整形中的应用

目的　提高大面积特重烧伤后期缺乏自体供皮来源整形患者的治疗效果 ,改善移植皮肤的形态和功能。方法　应用自制无细胞真皮基质与自体刃厚皮片复合移植 ,修复烧伤瘢痕松解整形的创面以改善功能形态。结果　 1 2例患者应用本方法治疗 ,1例因感染致部分植皮坏死 ,其余均完全成活 ,未见排异反应 ,与单纯自体薄皮片移植对比观察 ,愈后表皮平坦光滑 ,质地柔软 ,皮肤可捏起 ,色泽较正常皮肤略深 ,较刃厚皮移植满意 ,功能良好 ,与全厚或中厚皮片移植相似 ,优于薄的断层皮片或刃厚皮片。结论　无细胞真皮基质与自体薄皮片复合是比较理想的修复材料     

兔无细胞真皮基质的研制

目的：探讨制备兔无细胞真皮基质（ADM）的最佳方法。方法：选用三种不同的去表皮处理液，即高渗NaCl溶液，dispaseⅡ分离酶和嗜热蛋白酶（thermolysin)，结合去污剂0.5%十二烷基硫酸钠（SDS）处理，分别制备兔ADM，并对其进行组织学检测。结果：高渗NaCl-SDS制备的兔ADM尚有少量表皮残留，乳白色中夹杂浅黄色，组织学观察可见真皮中有较多细胞碎屑，而经dispaseⅡ-SDS和thernolysin-SDS制备的兔ADM表皮完全去除，呈乳白色，组织学观察发现真皮中已不见任何细胞成分，胶原纤维排列规则。电镜观察，上述三种方法制备的兔ADM基底膜结构均完整。结论 由dispaseⅡ-SDS法和thermolysin-SDS法制备的兔ADM达到了完全去细胞化，符合制备要求。     

血管内皮细胞联合同种异体神经移植修复长距离大鼠坐骨神经缺损

目的:探讨血管内皮细胞(EC)联合去细胞同种异体神经移植修复长距离大鼠坐骨神经缺损的效果。方法:80只雌性Sprague-Dawley大鼠,20只取双侧1.5cm长坐骨神经,Hudson优化法制备去细胞同种异体神经(ANA);60只均于右侧建立1.5cm长坐骨神经缺损模型,随机分为反转吻合坐骨神经的自体神经(ANG)移植组、ANA移植组及ANA+EC移植组(n=20)。术后1、2、4、12周,每组各取5只进行测试,指标包括:坐骨神经功能指数(SFI)、电生理检查[动作电位潜伏延迟率(LDR)、神经传导速度恢复率(NCVRR)和复合肌动作电位恢复率(CMAPRR)]、最大强直收缩力恢复率(MTFRR)、腓肠肌湿重恢复率(MWRR)、微血管增生率(MVDPR),术后12周甲苯胺蓝染色下测量神经纤维数量、髓鞘厚度、G ratio,并行电镜观察。结果:术后早期,ANA+EC移植组大鼠SFI、MVDPR较ANA移植组改善明显(P0.05);术后晚期,ANA+EC移植组大鼠CMAPRR、MTFRR、MWRR较ANA移植组恢复更佳(P0.05);术后12周时,ANA+EC移植组再生神经数量和形态更接近ANG移植组。结论:对于长距离坐骨神经缺损的大鼠模型,使用载血管内皮细胞的去细胞同种异体神经进行神经移植修复,早期肌肉功能优于单独使用去细胞同种异体神经,晚期神经纤维的数量和质量更接近于自体神经移植。     

Comparison of two different surgical approaches to increase peri‐implant mucosal thickness: A randomized controlled clinical trial

1 Background

Current evidence supports the positive effect of adequate peri‐implant mucosal thickness (PMT) on both marginal bone level stability and esthetic outcomes. While the subepithelial connective tissue graft (sCTG) has been traditionally considered as the gold standard for peri‐implant mucosal augmentation, acellular dermal matrix (ADM) may be a valid alternative. The primary aim of this randomized clinical trial was to determine the clinical efficacy of ADM in the augmentation of PMT as compared to an autologous sCTG.

2 Methods

Patients who could benefit from peri‐implant mucosal augmentation at the time of implant placement were recruited. Participants were randomized to the control (simultaneous sCTG) or test (simultaneous ADM) group. The primary outcome in this study was changes in PMT between baseline and 16 weeks later. Keratinized mucosal width (KMW) changes, modified wound healing index (MWHI) variations and patient‐reported outcome measures (PROMs) were recorded, as well.

3 Results

A total of 20 participants were recruited per an a priori power analysis. There were no statistically significant differences between groups at baseline for any of the parameters analyzed. The gain in PMT at 1 mm, 3 mm, and 5 mm from the expected mucosal margin was 0.44 ± 2.04 mm, 1.20 ± 1.48 mm, and 1.20 ± 0.89 mm in the sCTG group, and 0.05 ± 1.57 mm, 0.85 ± 1.29 mm, and 1.45 ± 1.17 mm in the ADM group. No statistically significant differences in terms of PMT, KMW, and MWHI changes were observed between groups. The perceived discomfort was higher at 2 and 4 weeks for patients in the sCTG group.

4 Conclusion

ADM produces similar outcomes to sCTG in terms of mucosal augmentation at the time of implant placement.     

自体微粒皮与异体脱细胞微粒真皮混合移植对大鼠创面纤维连接蛋白和层粘连蛋白表达的影响

目的 探讨自体微粒皮与异体脱细胞微粒真皮混合移植对创面愈合的影响,并对有关机制做进一步研究.方法 Wistar大鼠作为供体,SD大鼠为受体,在SD大鼠背部建立全层皮肤损伤模型.90只SD大鼠分为5组,每组18只,第1组为自体微粒皮组;第2组为异体脱细胞微粒真皮移植组;第3、4、5组为混合移植组.混合移植组中自异体微粒皮的面积比例分别为:1∶1、1∶0.5、1∶0.25.术后第2、3、4周分别测量每组创面的愈合率,采集创面标本,做HE染色,检测纤维连接蛋白(FN)和层粘连蛋白(LN)、进行组间比较.结果 混合移植组与自体微粒皮移植组比较,混合移植组创面愈合率及FN、LN均高于自体微粒皮组,其中1∶0.25混合移植组最高,差异有统计学意义(P＜0.05或P＜0.01).结论 混合移植创面愈合率高于自体微粒皮移植,且自体微粒皮与异体脱细胞微粒真皮混合移植的面积比例按1∶0.25效果最佳,这可能与创面纤维连接蛋白和层粘连蛋白升高有关.     

异体脱细胞真皮基质与自体皮片复合移植的临床应用

目的:探讨异体脱细胞真皮基质与自体皮片复合移植修复大面积深度烧伤及瘢痕切除后皮肤缺损创面及其愈合后皮肤的外形和功能。方法:应用异体脱细胞真皮基质与自体刃厚皮片组成复合皮移植,以自体刃厚皮片移植作为对照,采用一步移植法治疗切痂后大面积深度烧伤创面及瘢痕切除后皮肤缺损共56例患者60处创面,观察术后皮片的成活情况、外形及功能恢复情况并随访。结果:60处创面全部愈合,移植皮片生长良好,瘢痕增生不明显,未见明显挛缩,皮肤弹性较好。在6～12个月的观察期内,自体刃厚皮片与异体脱细胞真皮基质复合移植后,功能和形态优于单纯自体刃厚皮片移植;随访2年复合移植未发现明显的排异反应。结论:异体脱细胞真皮基质与自体皮片复合移植修复大面积深度烧伤及瘢痕切除后皮肤缺损创面愈合良好,无瘢痕增生,皮肤外观功能满意,无排异反应。     

Factors associated with human papillomavirus vaccine-series initiation and healthcare provider recommendation in US adolescent females: 2007 National Survey of Children's Health

Objective

To identify factors associated with initiation of the human papillomavirus vaccine series and parental report of a healthcare provider recommendation of the human papillomavirus vaccine in adolescent females.

Design

Cross-sectional analysis of 2007 National Survey of Children's Health.

Participants

Parents of 12–17 year-old US adolescent females.

Main outcome measures

Associations of sociodemographic and healthcare factors with initiation of the human papillomavirus vaccine series and parental report of a healthcare provider recommendation of the human papillomavirus vaccine.

Results

Data were analyzed for 16,139 adolescent females. Almost 20% of adolescent females initiated the HPV vaccine series. Significantly higher proportions of adolescent females who initiated the human papillomavirus vaccine series vs. those who did not initiate the human papillomavirus vaccine series had a parental report of their healthcare provider recommending the human papillomavirus vaccine (84% vs. 20%). In multivariable analyses, adolescent females who were American Indian/Alaska Native, were multiracial, received the meningococcal vaccine, received the tetanus/tetanus–diphtheria/tetanus–diphtheria–acellular pertussis vaccine, or were poor had higher adjusted odds of initiating the human papillomavirus vaccine series; parental report of a healthcare provider recommendation of the human papillomavirus vaccine was associated with about 18 times the adjusted odds of initiating the human papillomavirus vaccine series. In separate multivariable analyses, adolescent females who were African-American and uninsured had lower adjusted odds of a parental report of a healthcare provider recommendation of the human papillomavirus vaccine.

Conclusion

Parental report of a healthcare provider recommendation is significantly associated with human papillomavirus vaccine-series initiation. African-American race/ethnicity and uninsurance were associated with lower odds of a parental report of a healthcare provider recommendation of the human papillomavirus vaccine. Routine healthcare provider recommendation of human papillomavirus vaccination might improve adolescent females’ human papillomavirus vaccination rates.     

自体微粒皮与异体脱细胞微粒真皮混合移植对大鼠创面MMP1、MMP10表达的影响

目的探讨自体微粒皮与异体脱细胞微粒真皮混合移植对创面愈合的影响与机制。方法实验用雄性wistar大鼠做为异体脱细胞真皮的供体,雌性SD大鼠作为受体,在其背部建立全层皮肤损伤模型,90只SD大鼠分为5组,每组18只,1、2组分别为自体微粒皮与脱细胞微粒真皮移植组,3、4、5组为自体微粒皮与异体脱细胞微粒真皮混合移植组,自体微粒皮与异体脱细胞微粒真皮的面积比例分别为:1:1、1:0.5、1:0.25,术后2、3、4周分别测量每组创面的愈合率,同时采集创面标本,做HE染色,并作MMP1、MMP10检测,进行组间比较。结果混合移植组创面愈合率均高于自体微粒皮组,其中1:0:25混合移植组升高最明显,差异有统计学意义(P﹤0.01);混合移植组与自体微粒皮移植组比较MMP1、MMP10除1:1混合移植组第4周外都有明显升高(P﹤0.05或P﹤0.01),且1:0.25混合移植组升高最明显。结论自体微粒皮与脱细胞微粒真皮混合移植创面愈合率高于自体微粒皮移植,且自体微粒皮与脱细胞微粒真皮混合移植的面积比例按1:0.25混合移植效果最佳,这可能与创面MMP1、MMP10升高有关。     

不同试剂脱除猪胸主动脉壁细胞的对比研究

目的:用不同方法去除猪胸主动脉壁细胞,并比较去细胞效果,为组织工程瓣膜或带瓣管道提供良好的实验材料。方法:采用十二烷基硫酸钠、胆脂酸钠、曲拉通（TritonX100）制备猪胸主动脉脱细胞基质。将实验分为十二烷基硫酸钠组、胆脂酸钠、曲拉通组和空白对照组。标本进行大体、光镜、电镜观察,力学性能的检测并做比较。结果:胆脂酸钠无法完全脱除主动脉壁内细胞,十二烷基硫酸钠和曲拉通都能完全脱除猪胸主动脉细胞,曲拉通较好地保持了胶原纤维和弹性纤维的原有排列和分布,并有较好的力学性能。后两者脱细胞时间无显著差别。结论:曲拉通可以成功用于制备大血管脱细胞基质,为组织工程瓣膜或带瓣管道的研究提供材料。