Retrograde perfusion in isolated perfused mouse lungs—Feasibility and effects on cytokine levels and pulmonary oedema formation

Retrograde lung vascular perfusion can appear in high‐risk surgeries. The present report is the first to study long‐term retrograde perfusion of isolated perfused mouse lungs (IPLs) and to use the tyrosine kinase ephB4 and its ligand ephrinB2 as potential markers for acute lung injury. Mouse lungs were subjected to anterograde or retrograde perfusion with normal‐pressure ventilation (NV) or high‐pressure ventilation (=overventilation, OV) for 4 hours. Outcome parameters were cytokine, ephrinB2 and ephB4 levels in perfusate samples and bronchoalveolar lavage (BAL), and the wet‐to‐dry ratio. Anterograde perfusion was feasible for 4 hours, while lungs receiving retrograde perfusion presented considerable collapse rates. Retrograde perfusion resulted in an increased wet‐to‐dry ratio when combined with high‐pressure ventilation; other physiological parameters were not affected. Cytokine levels in BAL and perfusate, as well as levels of soluble ephB4 in BAL were increased in OV, while soluble ephrinB2 BAL levels were increased in retrograde perfusion. BAL levels of ephrinB2 and ephB4 were also determined in vivo, including mice ventilated for 7 hours with normal‐volume ventilation (NVV) or high‐volume ventilation (HVV) with increased levels of ephB4 in HVV BAL compared to NVV. Retrograde perfusion in IPL is limited as a routine method to investigate effects due to collapse for yet unclear reasons. If successful, retrograde perfusion has an influence on pulmonary oedema formation. In BAL, ephrinB2 seems to be up‐regulated by flow reversal, while ephB4 is a marker for acute lung injury.     

Inferior mesenteric arteriovenous fistula: Case report and world-literature review

Arteriovenous fistulas between the inferior mesenteric artery and vein are rare, with only 26 primary and secondary cases described in the literature. Secondary fistulas occur following operations of the left hemicolon and manifest as abdominal pain, abdominal mass, gastrointestinal bleeding, colonic ischemia and portal hypertension. Symptom intensities are flow-dependent, and can range from minimal symptoms to severe heart failure due to left to right shunt. Diagnosis is usually established by radiological or intraoperative examination. Treatment options include embolization and/or surgical resection. Therapeutic decisions should be adapted to the unique characteristics of the fistula on an individual basis. A new case of a primary arteriovenous fistula is described and discussed along with a complete review of the literature. The patient in this report presented with signs and symptoms of colonic ischemia without portal hypertension. The optimal treatment for this patient required a combination of embolization and surgical operation. The characteristics of these rare inferior mesenteric arteriovenous fistulas are examined and some considerations concerning diagnostic and therapeutic strategies that should be followed are presented.     

Clinical and histopathological correlations of fecal calprotectin release in colorectal carcinoma

AIM:To determine calprotectin release before and after colorectal cancer operation and compare it to tumor and histopathological parameters.METHODS:The study was performed on patients with diagnosed colorectal cancer admitted for operation.Calprotectin was measured in a single stool sample before and three months after the operation using an enzymelinked immunosorbent assay(ELISA).Calprotectin levels greater than or equal to 50μg/g were considered positive.The compliance for collecting stool samples was assessed and the value of calprotectin was correlated to tumor and histopathological parameters of intra-and peri-tumoral inflammation.Surgical specimens were fixed in neutral buffered formalin and stained with hematoxylin and eosin.Staging was performed according to the Dukes classification system and the 7th edition tumor node metastasis classification system.Intra-and peri-tumoral inflammation was graded according to the Klintrup criteria.Immunohistochemical quantification was performed for MPO,CD45R0,TIA-1,CD3,CD4,CD8,CD57,and granzyme B.Statistical significance was measured using Wilcoxon signed rank test,Kruskal Wallis test and Spearman’s rank correlation coefficient as appropriate.RESULTS:Between March 2009 and May 2011,80 patients with colorectal cancer(46 men and 34 women,with mean age of 71±11.7 years old)were enrolled in the study.Twenty-six patients had rectal carcinoma,29 had left-side tumors,23 had right-side tumors,and2 had bilateral carcinoma.In total,71.2%of the patients had increased levels of calprotectin before the operation(median 205μg/g,range 50-2405μg/g)and experienced a significant decrease three months after the operation(46μg/g,range 10-384μg/g,P<0001).The compliance for collecting stool samples was 89.5%.Patients with T3 and T4 tumors had significantly higher values than those with T1 and T2 cancers(P=0.022).For all other tumor parameters(N,M,G,L,V,Pn)and location,no significant difference in calprotectin concentration was found.Furthermore,the calprotectin levels and histological grading of both peri-and intra-tumoral inflammation was not correlated.Additional testing with specific markers for lymphocytes and neutrophils also revealed no statistically significant correlation.CONCLUSION:Fecal calprotectin decreases significantly after colorectal cancer operation.Its value depends exclusively on the individual T-stage,but not on other tumor or histopathological parameters.     

Differences in Glycemic Variability Between Normoglycemic and Prediabetic Subjects

So far the criteria for NGT and abnormal glucose tolerance (AGT) are based on HbA1c and 75 g oGTT. We present data on GV and diurnal profiles in stratified cohorts with AGT versus controls. 28 NGT, 42 AGT (15 IGT, 11 IFG, 16 CGI) matched for age and BMI classified by 75 g oGTT underwent a CGM with test meal (TM). Diurnal profiles, glucose excursion after TM, and GV (SD, MAGE) were calculated for day 2 and 3. HbA1c, with its values of 5.5 ± 0.37% versus 5.65 ± 0.36%, was within normal range. Average interstitial glucose (AiG) was 5.84 ± 0.52 mmol/l) in NGT and 6.35 ± 0.65 mmol/l in AGT (P = .002). The 2 h incremental area under curve (iAUC) from TM until 2 h after TM was 1.94 ± 1.31 mmol/l*h versus 2.89 ( ± 1.75) mmol/l*h (P = .012), AiG 2 hours after TM was 5.99 ± 1.14 mmol/l*d versus 6.64 ± 1.30 mmol/l (P = .035). Peaks of AiG after TM were 7.69 ± 1.48 mmol/l*d versus 9.18 ± 1.67 mmol/l*d (P = .001). SD was significantly higher for AGT (1.12 ± 0.37 vs. 0.85 ± 0.32 mmol/l, P = .01) and MAGE 2.26 ± 0.84 vs. 1.60 ± 0.69 mmol/l, P = .005). In this comparative analysis NGT and AGT well matched for age, BMI, and comorbidities, CGM revealed significant differences in daytime AiG, pp glucose excursion and postprandial peaks. SD and MAGE was significantly higher for subjects with AGT. I Impaired glucose homeostasis a better characterizes degree of AGTe than HbA1c and 75 g OGTT.     

The Role of Sex Differences in Autophagy in the Heart During Coxsackievirus B3-Induced Myocarditis

Under normal conditions, autophagy maintains cardiomyocyte health and integrity through turnover of organelles. During stress, oxygen and nutrient deprivation, or microbial infection, autophagy prolongs cardiomyocyte survival. Sex differences in induction of cell death may to some extent explain the disparity between the sexes in many human diseases. However, sex differences in gene expression, which regulate cell death and autophagy, were so far not taken in consideration to explain the sex bias of viral myocarditis. Coxsackievirus B3 (CVB3)-induced myocarditis is a sex-biased disease, with females being substantially less susceptible than males and sex hormones largely determine this bias. CVB3 was shown to induce and subvert the autophagosome for its optimal viral RNA replication. Gene expression analysis on mouse and human, healthy and CVB3-infected, cardiac samples of both sexes, suggests sex differences in autophagy-related gene expression. This review discusses the aspects of sex bias in autophagy induction in cardiomyocytes.     

In vitro and in vivo Biocompatibility of Alginate Dialdehyde/Gelatin Hydrogels with and without Nanoscaled Bioactive Glass for Bone Tissue Engineering Applications

In addition to good mechanical properties needed for three-dimensional tissue engineering, the combination of alginate dialdehyde, gelatin and nano-scaled bioactive glass (45S5) is supposed to combine excellent cellular adhesion, proliferation and differentiation properties, good biocompatibility and predictable degradation rates. The goal of this study was to evaluate thein vitro and in vivo biocompatibility as a first step on the way to its use as a scaffold in bone tissue engineering. In vitro evaluation showed good cell adherence and proliferation of bone marrow derived mesenchymal stem cells seeded on covalently crosslinked alginate dialdehyde-gelatin (ADA-GEL) hydrogel films with and without 0.1% nano-Bioglass^®(nBG). Lactate dehydrogenase (LDH)- and mitochondrial activity significantly increased in both ADA-GEL and ADA-GEL-nBG groups compared to alginate. However, addition of 0.1% nBG seemed to have slight cytotoxic effect compared to ADA-GEL. In vivo implantation did not produce a significant inflammatory reaction, and ongoing degradation could be seen after four weeks. Ongoing vascularization was detected after four weeks. The good biocompatibility encourages future studies using ADA-GEL and nBG for bone tissue engineering application.