玻璃化保存工程化组织产品的实验与技术

目的:总结近年来玻璃化保存技术的新进展和多种工程化组织玻璃化保存的实验研究。探讨影响工程化组织低温保存的主要因素、评价指标等,以期指导玻璃化保存工程化组织的实验研究。资料来源:应用计算机检索Medline,EBSCO,ScienceDirect Onsite以及google scholar引擎中1980-02/2006-05关于细胞和组织低温保存的文献,检索词“tissue engineering,engineered tissue,cryopreservation,vitrification,ice-free cryopreservation,vitreous cryopreservation”,检索词被分别组合进行检索,限定文献语言种类为English。同时计算机检索万方数据库1980-02/2006-05关于细胞和组织低温保存的文献,检索词“组织工程,工程化组织,冻存,玻璃化保存”,限定文献语言种类为中文。资料选择:对资料进行初审,选出与研究关系密切的文献。纳入标准:研究对象为动物或人,包括基础与临床研究内容。重点选取与玻璃化保存技术基本原理相关以及具体的工程化构建物玻璃化保存相关的文献。排除标准:关于配子,胚胎和植物,食品等的玻璃化保存文章。资料提炼:共检索到122篇关于细胞和组织低温保存的文献,其中与本实验关系密切的文献17篇,间接相关的文献42篇,最终纳入31篇符合标准的文献。资料综合:组织工程产业化要求长期而稳定的保存包含活细胞的工程化组织产品,以及产品中细胞与材料的黏附。相对于传统的低温冻存技术而言,玻璃化保存因在保存过程中无细胞内外冰晶形成,可以改善复温后的细胞活力,并能保护细胞和支架材料之间的黏附。本文从近年来玻璃化保存技术的新进展和多种工程化组织玻璃化保存的实验研究进行综述,分析了玻璃化保存液要求高浓度,对细胞有非特异毒性损伤,对悬浮单细胞的玻璃化保存能得到较高的细胞存活,而与支架材料结合的种子细胞存活除受到冻存试剂和流程的影响外还受到自身结构的影响。结论:玻璃化保存是较好的生物系统保存方法,可以为工程化组织产品提供可靠的保存,但急需发现新的低毒高效的玻璃化试剂以及优化保存流程。     

Factors predicting the use of therapeutic hypothermia and survival in unconscious out-of-hospital cardiac arrest patients admitted to the ICU

Introduction

Therapeutic hypothermia (TH) after out-of-hospital cardiac arrest (OHCA) was adopted early in Norway. Since 2004 the general recommendation has been to cool all unconscious OHCA patients treated in the intensive care unit (ICU), but the decision to cool individual patients was left to the responsible physician. We assessed factors that were associated with use of TH and predicted survival.

Method

We conducted a retrospective observational study of prospectively collected cardiac arrest and ICU registry data from 2004 to 2008 at three university hospitals.

Results

A total of 715 unconscious patients older than 18 years of age, who suffered OHCA of both cardiac and non-cardiac causes, were included. With an overall TH use of 70%, the survival to discharge was 42%, with 90% of the survivors having a favourable cerebral outcome. Known positive prognostic factors such as witnessed arrest, bystander cardio pulmonary resuscitation (CPR), shockable rhythm and cardiac origin were all positive predictors of TH use and survival. On the other side, increasing age predicted a lower utilisation of TH: Odds Ratio (OR), 0.96 (95% CI, 0.94 to 0.97); as well as a lower survival: OR 0.96 (95% CI, 0.94 to 0.97). Female gender was also associated with a lower use of TH: OR 0.65 (95% CI, 0.43 to 0.97); and a poorer survival: OR 0.57 (95% CI, 0.36 to 0.92). After correcting for other prognostic factors, use of TH remained an independent predictor of improved survival with OR 1.91 (95% CI 1.18-3.06; P <0.001). Analysing subgroups divided after initial rhythm, these effects remained unchanged for patients with shockable rhythm, but not for patients with non-shockable rhythm where use of TH and female gender lost their predictive value.

Conclusions

Although TH was used in the majority of unconscious OHCA patients admitted to the ICU, actual use varied significantly between subgroups. Increasing age predicted both a decreased utilisation of TH as well as lower survival. Further, in patients with a shockable rhythm female gender predicted both a lower use of TH and poorer survival. Our results indicate an underutilisation of TH in some subgroups. Hence, more research on factors affecting TH use and the associated outcomes in subgroups of post-resuscitation patients is needed.     

International comparative field study of N8 evaluating factor VIII assay performance

Summary. Discrepancies between the one‐stage clotting assay and the chromogenic method, and also among different variations of each method, have been a significant challenge for one B‐domain deleted FVIII product. N8 is a B‐domain truncated FVIII product developed by Novo Nordisk. The comparison of N8 and Advate^® was performed in an international, multicentre, randomized and blinded field study of simulated postinfusion samples. Overall, Advate^® and N8 performed similarly in the one‐stage assay. In the one‐stage clotting assay, the measured mean FVIII levels of Advate^® vs. N8 were 0.046/0.047, 0.24/0.24, 0.58/0.60 and 0.82/0.83 IU mL^?1 for the target values of 0.03, 0.2, 0.6 and 0.9 IU mL^?1, respectively. In the chromogenic assays, the concentration estimates showed a tendency towards higher N8 values as compared with Advate^®; the measured FVIII levels of Advate^® vs. N8 were 0.030/0.032, 0.22/0.24, 0.65/0.74 and 0.98/1.08 IU mL^?1 for the target values of 0.03, 0.2, 0.6 and 0.9 IU mL^?1, respectively. In the one‐stage assays, the measured values were above 150% of target at the lowest concentration, decreasing to around 90% of target at the highest concentration. In contrast, the chromogenic assays were close to target at the lowest concentration and consistently above target at the three highest concentrations. Therefore, the ratio of chromogenic/one‐stage potencies was concentration dependent, ranging from 0.66 to 1.30. The SSC plasma standard was similar in both. Assay variability was similar for both compounds. The results show that N8 can be reliably measured in plasma without the need for a separate N8 standard.     

Endoscopic ultrasonography and computed tomography scanning for preoperative staging of colonic cancer

Purpose

With an increasing demand for more accurate preoperative staging methods for colon cancer, we aimed to compare preoperative tumour (T)- and nodal (N)-stage in patients with left-sided colon cancer by endoscopic ultrasonography (EUS) and computed tomography (CT) with post-operative histology as gold standard.

Methods

A total of 44 patients were prospectively recruited at Herlev and Roskilde University Hospitals during November 2014–January 2016. Thirty-five patients were included in the final analysis and underwent EUS, CT and surgery within 2 weeks. Diagnostic values were evaluated for “low risk” (T1+T2+T3 with ≤5 mm extramural invasion) and “high risk” (T3 with >5 mm of extramural spread + T4) colonic cancer.

Results

Sensitivity and specificity in “low risk” colonic cancer evaluated with EUS was 0.90 [0.74;0.98] and 0.75 [0.19;0.99] and with CT 0.96 [0.80;0.99] and 0.25 [<0.01;0.81]. EUS and CT were poor in predicting N0 or N+ disease.

Conclusions

The sensitivity of EUS and CT were good and comparable regarding T-stage evaluation, while EUS had a significantly higher specificity in the evaluation of “low risk” tumours. The results obtained for “high risk” colonic cancer were difficult to evaluate due to small patient numbers. EUS could be considered as a supplement to CT scans in selecting patients for neoadjuvant therapies, or local transmural treatment, in the future.

Trial registration

NCT02324023

     

An Unusual Cause of Vaginal Bleeding and Abdominal Pain -Prolapsed Ureterocele

EDITORIAL COMMENT: The editor has never seen a urinary tract vulval mass like this. However, in 1963 at the Austin Hospital, Melbourne, he saw and unfortunately failed to photograph, a pink vulval mass in a woman with paraplegia who had turned her bladder inside out and passed it per urethra like an intussusception. The nature of the mass became apparent when urine spurted from the ureteric orifices. This woman was managed by a urologist by ureteric transplantation into an ileal loop.     

First Antenatal Visit Haematocrit and Pregnancy Induced Hypertension

First antenatal visit haematocrit values during the first and second trimesters were retrospectively collected from 546 nulliparas with singleton pregnancies. The results were analysed for correlation with development of pregnancy induced hypertension (PIH) later in pregnancy. It was found that women with higher haematocrit values, especially over 0.40, had an increased risk of developing PIH. However, there appeared to be no absolute level of haematocrit which had sufficient discriminative value to be useful in clinical practice.