Early Anastomotic Repair in the Rat Intestine is Affected by Transient Preoperative Mesenteric Ischemia

Introduction  During bowel surgery, perioperative blood loss and hypotension can lead to transient intestinal ischemia. Recent preclinical studies reveal that the strength of intestinal anastomoses can be compromised after reperfusion. So far, this phenomenon has not been investigated in the very first days of healing when wound strength is lowest. Material and Method  Ischemia was induced in rats by clamping both the superior mesenteric artery and ileal branches for 30 min. Immediately after declamping, anastomoses were constructed in both terminal ileum and descending colon. The same was done in control groups after sham-ischemia. Anastomotic bursting pressure and breaking strength were measured immediately after operation (day 0) and after 1, 2, or 3 days. Anastomotic hydroxyproline content, gelatinase activity, and histology were analyzed. Results and Discussion  In ileal anastomoses, at day 1, both the breaking strength and bursting pressure were significantly (p < 0.05) lower in the ischemic group, while at day 2, this was the case for the bursting pressure only. In the colon, the bursting pressure in the ischemic group was lower at day 1. Anastomotic hydroxyproline content remained unchanged. Increased presence of the various gelatinase activities was found in ileum only at day 0 and in colon at days 1 and 2. Histological mucosal damage was found in ischemia–reperfusion groups. Conclusion  Transient mesenteric ischemia can negatively affect anastomotic strength during the very first days of healing, even if the tissue used for anastomotic construction looks vital.     

Opportunities for the replacement of animals in the study of nausea and vomiting

Nausea and vomiting are among the most common symptoms encountered in medicine as either symptoms of disease or side effects of treatments. Developing novel anti-emetics and identifying emetic liability in novel chemical entities rely on models that can recreate the complexity of these multi-system reflexes. Animal models (especially the ferret and dog) are the current gold standard; however, the selection of appropriate models is still a matter of debate, especially when studying the subjective human sensation of nausea. Furthermore, these studies are associated with animal suffering. Here, following a recent workshop held to review the utility of animal models in nausea and vomiting research, we discuss the limitations of some of the current models in the context of basic research, anti-emetic development and emetic liability detection. We provide suggestions for how these limitations may be overcome using non-animal alternatives, including greater use of human volunteers, in silico and in vitro techniques and lower organisms.     

一叶萩碱全合成的研究

以1,4-环己二酮为原料经与哌啶缩合、还原、乙酸汞环合、碱催化分子内缩合等11步反应完成了一叶萩碱的全合成。合成品的熔点及光谱数据与天然一叶萩碱的熔点及光谱数据一致。     

More effective blood transfusion policies in elective surgery by objective transfusion guidelines

The blood ordering practice in a general hospital was evaluated for 22 types of frequently scheduled elective surgical procedures. The following parameters were used: the C/T ratio (crossmatched/transfused ratio) for appraising the tendency to over-order in terms of frequency, the BOQ (blood ordering quotient) to establish whether the appropriate amount is ordered, and the transfusion probability to establish whether the risk accompanying the procedure warrants crossmatching blood. Using the results a list was compiled grouping the procedures as follows: 1. transfusion probability greater than 30%: type & screen and crossmatching of blood before the surgical procedure; 2. transfusion probability less than 30%: type & screen; 3. transfusion probability = 0%: no type & screen (remaining procedures). The number of units crossmatched for surgical procedures in the first group is in accordance with actual expected needs. Owing to the use of this list of expected haemotherapy requirements the number of patients for whom blood is crossmatched preoperatively has diminished from 76.5% to 29.8%. Furthermore, the C/T ratio has decreased from 3.33 to 1.45 with a practically unchanged transfusion probability (the mean for 22 types of surgical procedures). The number of crossmatches for these procedures has shown a 56% decrease. The use of the list of expected requirements has led to an annual saving of Dfl. 20,000-on laboratory expenses.