Experimental models of high-risk bowel anastomosis in rats:A systematic review

BACKGROUND Anastomotic leaks remain one of the most dreaded complications in gastrointestinal surgery causing significant morbidity,that negatively affect the patients’quality of life.Experimental studies play an important role in understanding the pathophysiological background of anastomotic healing and there are still many fields that require further investigation.Knowledge drawn from these studies can lead to interventions or techniques that can reduce the risk of anastomotic leak in patients with high-risk features.Despite the advances in experimental protocols and techniques,designing a high-quality study is still challenging for the investigators as there is a plethora of different models used.AIM To review current state of the art for experimental protocols in high-risk anastomosis in rats.METHODS This systematic review was performed according to The Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines.To identify eligible studies,a comprehensive literature search was performed in the electronic databases PubMed(MEDLINE)and Scopus,covering the period from conception until 18 October 2023.RESULTS From our search strategy 102 studies were included and were categorized based on the mechanism used to create a high-risk anastomosis.Methods of assessing anastomotic healing were extracted and were individually appraised.CONCLUSION Anastomotic healing studies have evolved over the last decades,but the findings are yet to be translated into human studies.There is a need for high-quality,well-designed studies that will help to the better understanding of the pathophysiology of anastomotic healing and the effects of various interventions.

A Method to Determine the Incident Wave Boundary Conditions and Its Application

When studying the harbor water tranquility, cases are often confronted as that the verification point is not located on the generation line or that the angle between the generation line and the isobath is so large that the differences of the wave climates along the generation line can not be ignored. For these cases, the incident boundary conditions are difficult to evaluate. In order to solve this problem, a combined wave model is developed in the present paper based on the Boussinesq equation and the wave action balance equation. Instead of the one-line wave generation method, a multi-line generation method is proposed for the combined model. Application of this method is given to a case that the harbor is designed with two entrances and the angle between the generation line and the isobath is large and the results are shown reasonable. We suggest that the wave generation method on multi-lines might also be introduced to the wave physical model as the replacement for the one-line generation method.

Effects of chimeric molecule of recombinant Dsg3EC_(1-2) with toxin PE40 on T and B lymphocytes in Pemphigus Vulgaris

Objective:To observe the effects of the recombinant chimeric toxin Dsg3EC 1-2PE40 on T and B lymphocytes isolated from Pemphigus Vulgaris (PV) patients to further study its biological therapeutic function for PV. Methods:Recombinant chimeric toxin Dsg3EC 1-2PE40 was first identified, expressed and purified, and then its effects on T and B lymphocytes of PV patients in vitro were detected and quantified by ELISPOT assay and MTT assay.Results:The purity of the expressed protein Dsg3EC 1-2PE40 was up to 80%. In ELISPOT assay, with Dsg3EC 1-2PE40, the overall number of B cells that produce anti-Dsg3 antibodies among PV patients was only about 60% of the comparable number with Dsg3EC 1-2. The proliferation of T cells of PV patients was inhibited markedly by Dsg3EC 1-2PE40. There was significant difference between the different groups with Dsg3EC 1-2PE40 and Dsg3EC 1-2.Conclusion:The recombinant chimeric toxin Dsg3EC 1-2PE40 decrease the number of B cells that produce anti-Dsg3 antibodies in PV patients and can inhibit or kill T cells of PV patients in vitro.

Comparison of Three Methods of Protein Extraction from Dermatophagoides Pteronyssinus for Two-dimensional Electrophoresis

Obiective To explore an effective method of Dermatophagoides pteronyssinus protein extraction suitable for two-dimensional electrophoresis （2-DE） analysis. Methods The extracts of Dermatophagoides pteronyssinus were prepared with Coca＇s solution, lysis buffer of 2-DE, and Trizol reagent, respectively. Bicinchoninic acid （BCA） assay was used to determine the total protein concentration of the samples. The efficiency of different protein extraction methods were evaluated with 2-DE analysis. Results The concentrations of extracted protein by methods of Coca＇s solution, lysis buffer, and Trizol reagent were 0.63 g/L, 0.90 g/L, and 0.80 g/L, respectively. The 2-DE analysis results showed that some protein spots in low molecular weight （LMW） range could be detected with the Coca＇s solution method. With the lysis buffer of 2-DE method, more protein spots in LMW range could be detected, while the medium molecular weight （MMW） protein spots were absent. Several MMW protein spots （174-178 kD and 133 kD） and more LMW protein spots were detected withTrizol reagent method. Conclusions Among Coca＇s solution, lysis buffer of 2-DE, and Trizol reagent, the concentration of extracted protein of Dermatophagoides pteronyssinus by lysis buffer of 2-DE is the highest. However, most protein components of Dermatophagoides pteronyssinus purified mite bodies can be extracted by Trizol reagent, which may generally reflect the whole profile of Dermatophagoides pteronyssinus allergens.

Paeonol Induces Vasodilatation in Rat Mesenteric Artery via Inhibiting Extracellular Ca^(2+) Influx and Intracellular Ca^(2+) Release

To investigate the vasodilative effect of paeonol in rat mesenteric artery and the mechanisms responsible for it. Methods： Rats were anaesthetized and sacrificed. The superior mesenteric artery was removed, dissected free of adherent tissue and cut into 2.0 mm long cylindrical segments. Isometric tension of artery rings was recorded by a myograph system in vitro. Concentration-relaxation curves of paeonol （17.8 μmol/L to 3.16 mmol/L） were recorded on artery rings precontracted by potassium chloride （KCI） and concentration-contraction curves of KCI, 5-hydroxytryptamine （5-HT）, noradrenaline （NA） or calcium chloride （CaCI2） were recorded in the presence of paeonol （10^-4.5, 10^-3.8, 10^-3.5 tool/L） respectively. And also, concentration- relaxation curves of paeonol were recorded in the presence of different potassium channel inhibitors and propranolol on rings precontracted with KCI respectively. To investigate the role of intracellular Ca2. release from Ca2. store, the contraction induced by NA （100μmol/L） and CaCI2 （2 mmol/L） in Ca^2＋ free medium was observed in the presence of paeonol respectively. Results： Paeonol relaxed artery rings precontracted by KCI in a concentration-dependent manner and the vasodilatation effect was not affected by endothelium denudation. Paeonol significant decreased the maximum contractions （Emax） induced by KCI, CaCl2, NA and 5-HT, as well as Emax induced by NA and CaCI2 in Ca^2＋-free medium, suggesting that paeonol dilated the artery via inhibiting the extracellular Ca2. influx mediated by voltage-dependent calcium channel, and receptor-mediated Ca^2＋-influx and release. Moreover, none of glibenclamide, tetraethylammonium, barium chlorded and propranolol affected the paeonol-induced vasodilatation, indicating that the vasodilatation was not contributed to ATP sensitive potassium channel, calcium-activated potassium channel, inwardly rectifying potassium channel, and β-adrenoceptor. Conclusion： Paeonol induces non-endothelium dependent-vasodilatation in rat mesenteric artery via inhibiting voltage-dependent calcium channel-mediated extracellular Ca^2＋ influx and receptor-mediated Ca^2＋ influx and release.