膝关节置换术后骨密度变化的研究进展

目的总结膝关节置换术后骨密度的变化及其诊断方式、影响因素和药物防治研究进展。方法查阅近年国内外有关文献，对骨密度评估测量方式的优缺点、膝关节置换术后骨密度的变化趋势及其影响因素，以及药物防治疗效差异进行总结。结果膝关节置换术后全身骨密度及假体周围平均骨密度总体呈下降趋势，与检测时患者体位、年龄、体质量、日常活动、假体固定方式、假体设计以及假体材料等因素密切相关。狄诺塞麦、双膦酸盐和特立帕肽等药物能够减少膝关节置换术后骨密度降低程度。结论膝关节置换术后骨密度呈下降趋势，但发生机制尚不明确，与多种因素相关。目前，抑制骨吸收药物对于膝关节置换术后骨密度降低有一定效果，但远期疗效有待进一步探究。     

改性壳聚糖基导电复合材料神经导管的体内降解及组织相容性观察

目的探讨改性壳聚糖基导电复合材料神经导管的体内降解及组织相容性，以期为组织工程神经构建提供新的支架材料。方法采用微乳液聚合法合成纳米聚吡咯（polypyrrole，PPy），与壳聚糖共混后注入定制的成管模型，冷冻干燥及脱酸后，制成改性纳米 PPy/壳聚糖复合材料导管（记作 CP 导管）；再经不同程度乙酰化（乙酰化反应时间分别为 30、60、90 min）改性，制备不同乙酰度的 CP 导管（记作 CAP1、CAP2、CAP3 导管）。各导管予红外光谱、扫描电镜进行表征，使用四探针电导仪测定电导率。取 30 只雌性 SD 大鼠，于背部左、右侧各制备 4 个皮下筋膜隧道，分别植入上述导管。术后 2、4、6、8、10、12 周取材，大体观察导管形态及完整性、扫描电镜观察导管微观结构、测量导管降解率，以观察导管体内降解性能；行 HE 染色及抗巨噬细胞免疫荧光染色，观察导管体内组织相容性。结果经表征证实乙酰化改性后的各导管 1 562 cm^–1左右的酰胺Ⅱ谱带增强，表示壳聚糖乙酰化改性成功。各导管均具备导电性能，组间电导率差异无统计学意义（P>0.05）。扫描电镜观察示各导管表面相对光滑、结构致密，无明显差异。导管植入体内后，随时间延长均出现一定程度塌陷，其中 CAP3 导管尤为明显；亦出现不同程度质量丢失，且乙酰化度越高，质量变化越大（P<0.05）。扫描电镜观察示植入 12 周后材料出现较多孔隙，且随着乙酰化度增加，孔隙呈增大趋势。组织学观察显示术后早期各导管均有较多巨噬细胞、淋巴细胞浸润，随着植入时间延长，淋巴细胞有所减少、成纤维细胞增多、胶原纤维增生明显。 结论不同乙酰度的改性壳聚糖基导电复合材料神经导管均有较好的体内生物相容性、可导电、可降解，且降解性与乙酰度相关，有望为组织工程神经构建提供一种新的支架材料。     

计算流体力学在组织工程中的应用进展

目的综述计算流体力学（computational fluid dynamics，CFD）在组织工程中的应用进展。方法广泛查阅 CFD 应用于组织工程的相关文献，主要对 CFD 用于生物反应器设计改良或优化、模拟体外组织再生过程中的流体动力学和细胞生长动力学等方面进行综述。结果CFD 的模拟预测能力可为生物反应器的设计优化和体外组织工程组织培养提供重要的指导作用，且结合实验研究能进一步提高模型预测结果的准确性。结论CFD 作为新兴和有效的研究工具，已在组织工程中展现出独特优势并取得显著进展，但更全面、准确地模拟组织再生全过程仍需进一步研究。     

Early-rectal Cancer Treatment: A Decision-tree Making Based on Systematic Review and Meta-analysis

Local excision (LE) has arisen as an alternative to total mesorectal excision for the treatment of early rectal cancer. Despite a decreased morbidity, there are still concerns about LE outcomes.This systematic-review and meta-analysis design is based on the “PICO” process, aiming to answer to three questions related to LE as primary treatment for early-rectal cancer, the optimal method for LE, and the potential role for completion treatment in high-risk histology tumors and outcomes of salvage surgery.The results revealed that reported overall survival (OS) and disease-specific survival (DSS) were 71%–91.7% and 80%–94% for LE, in contrast to 92.3%–94.3% and 94.4%–97% for radical surgery. Additional analysis of National Database studies revealed lower OS with LE (HR: 1.26; 95%CI, 1.09–1.45) and DSS (HR: 1.19; 95%CI, 1.01–1.41) after LE. Furthermore, patients receiving LE were significantly more prone develop local recurrence (RR: 3.44, 95%CI, 2.50–4.74). Analysis of available transanal surgical platforms was performed, finding no significant differences among them but reduced local recurrence compared to traditional transanal LE (OR:0.24;95%CI, 0.15–0.4). Finally, we found poor survival outcomes for patients undergoing salvage surgery, favoring completion treatment (chemoradiotherapy or surgery) when high-risk histology is present.In conclusion, LE could be considered adequate provided a full-thickness specimen can be achieved that the patient is informed about risk for potential requirement of completion treatment. Early-rectal cancer cases should be discussed in a multidisciplinary team, and patient's preferences must be considered in the decision-making process.     

Prevalence and mortality of patients with palliative needs in an acute respiratory setting

IntroductionNECPAL is a tool for identification of patients with advanced chronic disease in need of palliative care. The main objective of the study is to know the prevalence of patients with palliative needs in an acute respiratory ward in a Spanish tertiary hospital using NECPAL. A second objective of the study is to know the annual mortality rate of these patients.Materials and methodsCross sectional study and prospective monitoring of a cohort identified as palliative patients with the NECPAL tool for 12 months. Patient identification was performed in patients admitted to the respiratory ward of our hospital for longer than 3 days. We have assessed the annual vital status (deceased or not deceased) of patients and have recorded demographics, clinical and functional data, as well as the use of healthcare resources.ResultsWe monitored a cohort of 363 patients. Of them, 87 patients (24.3%) (IC 95% 19–30) were identified as NECPAL positive. 60% of patients (n = 64) died within 12 months of their admission. There was no significant difference in the mortality ratio of oncologic versus non oncologic patients. In a multivariable analysis, mortality was associated with demand by patients or relatives for palliative care and with the presence of specific disease progression markers or indicators.Conclusionsprevalence of patients with palliative needs in acute respiratory wards is high (one out of four patients). 60% of the patients identified as NECPAL positive in our cohort died in the first 12 months. Training of healthcare professionals as well as availability of appropriate resources are indispensable factors to improve care of this population.     

Associations and community health workers: analysis and time trends over ten years of training-action

ObjectiveTo analyse the profile of the persons and associations that participated in the course, quantify peer education activities and analyse their evolution.MethodA quantitative study using an analysis of the course records from 2009 to 2018 was designed for this purpose inside mihsalud program designed to promote health amongst persons in vulnerable situations in the city of Valencia (Spain). It offers a yearly training-action course of community health workers (CHW) that is attended by persons who have been proposed by associations. The associations were defined according to their population (immigrant, local or intercultural) and the CHWs according to gender, country of birth, year of course, association and continuity after training. Means and confidence intervals were calculated at 95% and a bivariate analysis was conducted in order to compare the activities that took place in 2009 to 2013 with those of 2014 to 2018. The time trends were analysed by applying linear regression models that included the different years studied as the dependent variable.Results201 CHW of 31 nationalities were trained, 81.6% (95% confidence interval [95% CI]: 75.5-86.7] were women. Eighty-two associations participated, 51.2% (95% CI: 39.9-62.4] worked with culturally diverse populations. Participation by associations (p = .017) and CHWs (p = .377) increased in a statistically significant manner over the years. After the course, 35.3% (95% CI: 28.7-42.4] of the CHWs continued to collaborate voluntarily in the associations.ConclusionsThe results of the CHW training-action course improve over time given that a significant increase in participation by associations and women can be seen, along with a greater number of activities completed during the training. One effect of this is that CHWs are contracted or carry out voluntary activities in the associations.