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Background: Diabetes mellitus (DM) induces cardiac and cerebral microvascular dysfunction via increased glycation, oxidative stress and endothelial activation. Liraglutide, a glucagon-like peptide-1 analogue, inhibited NOX2 and adhesion molecules in isolated endothelial cells. Here, we have studied how Liraglutide affects advanced glycation, NOX expression and inflammation of the cardiac, cerebral and renal microvasculature in diabetic rats., Methods: DM was induced in Sprague-Dawley rats (n = 15) via intraperitoneal streptozotocin (STZ) injection (60 mg/kg bodyweight). Ten control rats remained nondiabetic. From day 9 post-STZ injection, Liraglutide (200 μg/kg bodyweight; n = 7) or vehicle (n = 8) was injected subcutaneously daily until termination on day 29. The advanced glycation endproduct N-ε-(carboxymethyl)lysine (CML), NOX2, NOX4, ICAM-1 and VCAM-1 were subsequently immunohistochemically analysed and quantified to compare Liraglutide treatment with placebo., Results: In the heart, Liraglutide treatment significantly reduced the DM-increased scores/cm 2 for CML in both ventricles (from 253 ± 53 to 72 ± 12; p = .003) and atria (343 ± 29 to 122 ± 8; p = .0001) and for NOX2, ICAM-1 and VCAM-1, but not for NOX4. Also in the cerebrum and cerebellum of the brain, Liraglutide significantly reduced the scores/cm 2 for CML (to 60 ± 7 (p = .0005) and 47 ± 13 (p = .02), respectively), and for NOX2 and NOX4. In the kidney, the DM-induced expression of ICAM-1 and VCAM-1 was decreased in the blood vessels and glomeruli by Liraglutide treatment. Liraglutide did not affect blood glucose levels or bodyweight., Conclusions: Our study implies that Liraglutide protects the cardiac, cerebral and renal microvasculature against diabetes-induced dysfunction, independent of lowering blood glucose in a type 1 diabetes rat model., (© 2022 The Authors. European Journal of Clinical Investigation published by John Wiley & Sons Ltd on behalf of Stichting European Society for Clinical Investigation Journal Foundation.)

Background: Infections with potentially cardiotropic viruses are associated with the development of atrial fibrillation (AF). However, whether direct viral infection of the atria is involved in the pathogenesis of AF is unclear. We have therefore analysed the presence of cardiotropic viral genomes in AF patients., Methods: Samples of left atrial tissue were obtained from 50 AF patients (paroxysmal, n = 20; long-standing persistent/permanent, n = 30) during cardiac surgery and from autopsied control patients (n = 14). Herein, the presence of PVB19, EBV, CMV, HHV‑6, adenovirus and enterovirus genomes was determined by polymerase chain reaction. The densities of CD45+ and CD3+ cells and fibrosis in the atria were quantified by (immuno)histochemistry., Results: Of the tested viruses only the PVB19 genome was detected in the atria of 10% of patients, paroxysmal AF (2 of 20) and long-standing persistent/permanent AF (3 of 30). Conversely, in 50% of controls (7 of 14) PVB19 genome was found. No significant association was found between PVB19 and CD45+ and CD3+ cells, or between the presence of PVB19 and fibrosis, in either control or AF patients., Conclusion: The presence of viral genomes is not increased in the atria of AF patients. These results do not support an important role for viral infection of the atria in the pathogenesis of AF., (© 2022. The Author(s).)

Background: Burns induce a boost in local and systemic complement levels as well as immune cell infiltration in the burn wound, which may negatively affect wound healing., Objective: In this study, the effects of long-term treatment with complement inhibitor C1 esterase inhibitor (C1inh) on post-burn inflammation and wound healing parameters were analyzed in time up to 60 days post-burn., Methods: Burned pigs were treated either with or without C1inh up to 15 days post-burn. Burn wound biopsies and blood were collected at different time points up to 60 days post-burn. Thereafter, complement in blood as well as complement and immune cells in the wound, capillary leakage, necrosis, reepithelialization and wound contraction were quantified., Results: No significant differences in complement C3 blood levels were observed at any time point between C1inh-treated and control pigs. In the wound, complement C4 levels were significantly lower in the C1inh group than in controls at day 3-6 and 21-30 post-burn. Similarly, C3 levels, neutrophil and macrophage infiltration in the wound were, although not statistically significant, reduced in C1inh-treated pigs at day 9-14 post-burn. No differences in lymphocyte infiltration in the wound were found between C1inh and control pigs. C1inh-treated pigs also showed reduced capillary leakage. Despite these effects, no significant differences in the long-term wound healing parameters necrosis, reepithelialization and wound contraction were observed between C1inh and control pigs., Conclusion: In pigs, 15 days of C1inh treatment after burn, leads to a reduction in local inflammation and capillary leakage in the burn wound without affecting long-term wound healing parameters., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

Objective: Inflammation of the atria is an important factor in the pathogenesis of atrial fibrillation (AF). Whether the extent of atrial inflammation relates with clinical risk factors of AF, however, is largely unknown. This we have studied comparing patients with paroxysmal and long-standing persistent/permanent AF., Methods: Left atrial tissue was obtained from 50 AF patients (paroxysmal = 20, long-standing persistent/permanent = 30) that underwent a left atrial ablation procedure either or not in combination with coronary artery bypass grafting and/or valve surgery. Herein, the numbers of CD45+ and CD3+ inflammatory cells were quantified and correlated with the AF risk factors age, gender, diabetes, and blood CRP levels., Results: The numbers of CD45+ and CD3+ cells were significantly higher in the adipose tissue of the atria compared with the myocardium in all AF patients but did not differ between AF subtypes. The numbers of CD45+ and CD3+ cells did not relate significantly to gender or diabetes in any of the AF subtypes. However, the inflammatory infiltrates as well as CK-MB and CRP blood levels increased significantly with increasing age in long-standing persistent/permanent AF and a moderate positive correlation was found between the extent of atrial inflammation and the CRP blood levels in both AF subtypes., Conclusion: The extent of left atrial inflammation in AF patients was not related to the AF risk factors, diabetes and gender, but was associated with increasing age in patients with long-standing persistent/permanent AF. This may be indicative for a role of inflammation in the progression to long-standing persistent/permanent AF with increasing age.

IgG4 antibodies are unique to humans. IgG4 is associated with tolerance during immunotherapy in allergy, but also with pathology, as in pemphigus vulgaris and IgG4-related disease. Its induction is largely restricted to nonmicrobial antigens, and requires repeated or prolonged antigenic stimulation, for reasons poorly understood. An important aspect in generating high-affinity IgG antibodies is chemokine receptor-mediated migration of B cells into appropriate niches, such as germinal centers. Here, we show that compared to IgG1 B cells, circulating IgG4 B cells express lower levels of CXCR3, CXCR4, CXCR5, CCR6, and CCR7, chemokine receptors involved in GC reactions and generation of long-lived plasma cells. This phenotype was recapitulated by in vitro priming of naive B cells with an IgG4-inducing combination of T FH /T H2 cytokines. Consistent with these observations, we found a low abundance of IgG4 B cells in secondary lymphoid tissues in vivo, and the IgG4 antibody response is substantially more short-lived compared to other IgG subclasses in patient groups undergoing CD20 + B cell depletion therapy with rituximab. These results prompt the hypothesis that factors needed to form IgG4 B cells restrain at the same time the induction of a robust migratory phenotype that could support a long-lived IgG4 antibody response., (© 2020 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

In patients with burns, a massive inflammatory response is induced which negatively affects the healing process of the burn wound and additionally exerts systemic effects. An important factor herein is the complement system. Here we analyzed the effects of burns on complement and inflammatory cells both locally and systemically after burn in time in a pig burn wound model. In burned pigs, burn wound biopsies and blood were collected up to 60 days after burn. Complement in blood as well as complement and inflammatory cells in the burn wound and several organs were determined. In the blood, C3 was significantly increased after 9 to 60 days, whereas C4 after 21 to 30 days after burn. In the burn wound, C3 levels were significantly increased after 9 days and C4 after 3 days, whereafter both declined after 21 and 9 days, respectively. Neutrophils, macrophages, and lymphocytes were significantly increased in the burn wound after 3 days, all declined after 21 days after burn. In the heart, at 60 days after burn, an increase of neutrophils and macrophages was observed, mainly in the right atrium. In contrast to the heart, the inflammatory cell infiltrates in the lungs, liver, and kidney of burned pigs were lower than in control pigs. In pigs, following burn there is a prolonged increase in complement levels both in the burn wound and the blood and increased inflammatory cell infiltrate in the burn wound and the heart. However, complement levels in the burn wound and in the blood seem not to be correlated in time.

Background: Arterial blood pressure-induced shear stress causes endothelial cell apoptosis and inflammation in vein grafts after coronary artery bypass grafting. As the inflammatory protein type IIA secretory phospholipase A 2 (sPLA 2 -IIA) has been shown to progress atherosclerosis, we hypothesized a role for sPLA 2 -IIA herein., Methods: The effects of PX-18, an inhibitor of both sPLA 2 -IIA and apoptosis, on residual endothelium and the presence of sPLA 2 -IIA were studied in human saphenous vein segments (n = 6) perfused at arterial blood pressure with autologous blood for 6 hrs., Results: The presence of PX-18 in the perfusion blood induced a significant 20% reduction in endothelial cell loss compared to veins perfused without PX18, coinciding with significantly reduced sPLA 2 -IIA levels in the media of the vein graft wall. In addition, PX-18 significantly attenuated caspase-3 activation in human umbilical vein endothelial cells subjected to shear stress via mechanical stretch independent of sPLA 2 -IIA., Conclusions: In conclusion, PX-18 protects saphenous vein endothelial cells from arterial blood pressure-induced death, possibly also independent of sPLA 2 -IIA inhibition., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Objective: Although lymphocytic myocarditis (LM) clinically can mimic myocardial infarction (MI), they are regarded as distinct clinical entities. However, we observed a high prevalence (32%) of recent MI in patients diagnosed post-mortem with LM. To investigate if LM changes coronary atherosclerotic plaque, we analyzed in autopsied hearts the inflammatory infiltrate and stability in coronary atherosclerotic lesions in patients with LM and/or MI., Methods: The three main coronary arteries were isolated at autopsy of patients with LM, with MI of 3-6h old, with LM and MI of 3-6h old (LM+MI) and controls. In tissue sections of atherosclerotic plaque-containing coronary segments inflammatory infiltration, plaque stability, intraplaque hemorrhage and thrombi were determined via (immuno)histological criteria., Results: In tissue sections of those coronary segments the inflammatory infiltrate was found to be significantly increased in patients with LM, LM+MI and MI compared with controls. This inflammatory infiltrate consisted predominantly of macrophages and neutrophils in patients with only LM or MI, of lymphocytes in LM+MI and MI patients and of mast cells in LM+MI patients. Moreover, in LM+MI and MI patients this coincided with an increase of unstable plaques and thrombi. Finally, LM and especially MI and LM+MI patients showed significantly increased intraplaque hemorrhage., Conclusions: This study demonstrates prevalent co-occurrence of LM with a very recent MI at autopsy. Moreover, LM was associated with remodeling and inflammation of atherosclerotic plaques indicative of plaque destabilization pointing to coronary spasm, suggesting that preexistent LM, or its causes, may facilitate the development of MI., (Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.)

To diagnose lymphocytic myocarditis (LM), immunohistopathological examination of endomyocardial biopsies (EMBs) is used with a cutoff value of at least 14 leukocytes per mm 2 , composed of CD3- and CD68-positive cells. We hypothesized that a more common leukocyte marker, CD45, instead of CD3 could increase the diagnostic sensitivity. Hearts of mice with acute viral myocarditis (n = 9) and of controls (n = 7) and the EMB sampling area of the left ventricular posterior wall (LVPW) obtained from autopsied hearts of patients diagnosed with LM (n = 18) and controls (n = 6) were stained with anti-CD68, anti-CD3, and anti-CD45. When applying the threshold of at least 14 leukocytes per mm 2 , 33% of the mice would be diagnosed with LM with the use of CD3 + CD68 and 89% with the use of CD45 + CD68. In the EMB sampling area of autopsied hearts, using the cutoff value of at least 14 leukocytes per mm 2 , CD3 + CD68 could only confirm 17% of the diagnosis of LM, whereas CD45 + CD68 could confirm 50% of the LM cases. Moreover, we compared inflammation in the EMB sampling area of the LVPW to the remaining myocardium of the LVPW and observed a significant increase of CD45 + CD68 cells per mm 2 in patients with LM. In conclusion, the use of the common leukocyte marker CD45 increases the sensitivity of the diagnosis of LM. Furthermore, the inflammatory infiltrate in the EMB sampling area is significantly increased compared with the remaining LVPW, indicating that the sampling area constitutes the highest chance for histological diagnosis of LM., (Copyright © 2016 Elsevier Inc. All rights reserved.)

The complement system plays an important role in the inflammatory response subsequent to acute myocardial infarction (AMI). The aim of this study is to create a systematic overview of studies that have investigated therapeutic administration of complement inhibitors in both AMI animal models and human clinical trials. To enable extrapolation of observations from included animal studies toward post-AMI clinical trials, ex vivo studies on isolated hearts and proof-of-principle studies on inhibitor administration before experimental AMI induction were excluded. Positive therapeutic effects in AMI animal models have been described for cobra venom factor, soluble complement receptor 1, C1-esterase inhibitor (C1-inh), FUT-175, C1s-inhibitor, anti-C5, ADC-1004, clusterin, and glycosaminoglycans. Two types of complement inhibitors have been tested in clinical trials, being C1-inh and anti-C5. Pexelizumab (anti-C5) did not result in reproducible beneficial effects for AMI patients. Beneficial effects were reported in AMI patients for C1-inhibitor, albeit in small patient groups. In general, despite the absence of consistent positive effects in clinical trials thus far, the complement system remains a potentially interesting target for therapy in AMI patients. Based on the study designs of previous animal studies and clinical trials, we discuss several issues which require attention in the design of future studies: adjustment of clinical trial design to precise mechanism of action of administered inhibitor, optimizing the duration of therapy, and optimization of time point(s) on which therapeutic effects will be evaluated., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Background: Adipose-derived stromal cells (ASCs) are a promising new therapeutic option for patients with acute myocardial infarction (AMI). Previously, we found that ASCs coupled to antibody-targeted microbubbles (StemBells [StBs]) improved cardiac function when administered intravenously 7 days post-AMI in rats. In this study, we compared the efficacy of intravenous StB administration at different administration time points following AMI in rats., Methods: AMI, followed by reperfusion, was induced in four groups of male Wistar rats, which subsequently received an intravenous 1 × 10 6 StB bolus 1 day post-AMI (StB1; n = 8), 7 days post-AMI (StB7; n = 9), at both time points (StB1+7; n = 7) or neither (Control; n = 7). The effect onrdiac function was determined using echocardiography prior to AMI, 7 days post-AMI and 42 days post-AMI. The effect on infarct size and macrophages in the infarct core were determined (immuno)histochemically 42 days post-AMI., Results: At 42 days post-AMI, all three StB groups had a significantly improved fractional shortening compared with the control group. Between the StB-treated groups, the effects did not differ significantly at 42 days post-AMI. At 7 days post-AMI, the StB1 group had a significantly improved fractional shortening compared with the control and StB7 groups. No significant changes in infarct size or macrophage numbers were found compared with the control group for any StB group., Conclusions: StB administration resulted in long-term improvement of cardiac function, independent of the time point of administration. When administered at 1 day post-AMI, this improvement was already evident at 7 days post-AMI., (Copyright © 2017 International Society for Cellular Therapy. Published by Elsevier Inc. All rights reserved.)

Aims: Inflammation plays an important role in the pathogenesis of myocardial infarction (MI). Whether MI induces atrial inflammation is unknown however. Here, we analysed atrial inflammation in patients with MI and in rats with experimentally induced MI. The effect of the anti-inflammatory agent C1-esterase inhibitor (C1inh) on atrial inflammation in rats was also analysed., Methods: In the hearts of patients who died at different time points after MI (total n=24, mean age=60), neutrophils (myeloperoxidase-positive cells), lymphocytes (CD45-positive cells) and macrophages (CD68-positive cells) were quantified in the myocardium of the left and right atria and the infarcted left and non-infarcted right ventricles and compared with control patients (n=5, mean age=59). For the left and right atria, inflammatory cells were also quantified in the atrial adipose tissue. MI was induced in 17 rats, of which 10 were subsequently treated with C1inh for 6 days. Forty-two days post-MI, lymphocytes, macrophages and the endothelial inflammation marker N ε -(carboxymethyl)lysine (CML) were analysed in the myocardium of both the atria and ventricles., Results: In all investigated areas of the human hearts increased lymphocytes and macrophages were observed to a varying extent, especially between 6 h and 5 days following MI. Similarly, in rats MI resulted in an increase of inflammatory cells and CML in the atria. C1inh treatment decreased atrial inflammation., Conclusions: MI induces atrial inflammation in patients and in rats. C1inh treatment could counteract this MI-induced atrial inflammation in rats., (Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.)

Background: There is a clinical need for immunosuppressive therapy that can treat myocarditis patients in the presence of an active viral infection. In this study we therefore investigated the effects of colchicine, an immunosuppressive drug which has been used successfully as treatment for pericarditis patients, in a mouse model of coxsackievirus B3(CVB3)-induced myocarditis., Methods: Four groups of C3H mice were included: control mice (n=8), mice infected with CVB3 (1×10(5) PFU, n=10), mice with colchicine administration (2mg/kg i.p, n=5) and mice with combined CVB3 infection and colchicine administration (n=10). After three days, the heart, pancreas and spleen were harvested and evaluated using (immuno)histochemical analysis and CVB3 qPCR., Results: Mice were terminated at day 3 post-virus infection as colchicine treatment rapidly resulted in severe illness and mortality in CVB3-infected mice. Colchicine significantly decreased the number of macrophages in the heart in CVB3-infected mice (p<0.01) but significantly increased the number of neutrophils (p<0.01). In the pancreas, colchicine caused complete destruction of the acini in the CVB3-infected mice and also significantly decreased macrophage (p<0.01) and increased neutrophil numbers (p<0.01). In the spleen, colchicine treatment of CVB3-infected mice induced massive apoptosis in the white pulp and significantly inhibited the virus-induced increase of megakaryocytes in the spleen (p<0.001). Finally, we observed that colchicine significantly increased CVB3 levels in both the pancreas and the heart., Conclusions: Colchicine treatment in CVB3-induced myocarditis has a detrimental effect as it causes complete destruction of the exocrine pancreas and enhances viral load in both heart and pancreas., (Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.)

Successful stem cell therapy after acute myocardial infarction (AMI) is hindered by lack of engraftment of sufficient stem cells at the site of injury. We designed a novel technique to overcome this problem by assembling stem cell-microbubble complexes, named 'StemBells'. StemBells were assembled through binding of dual-targeted microbubbles (~3μm) to adipose-derived stem cells (ASCs) via a CD90 antibody. StemBells were targeted to the infarct area via an ICAM-1 antibody on the microbubbles. StemBells were characterized microscopically and by flow cytometry. The effect of ultrasound on directing StemBells towards the vessel wall was demonstrated in an in vitro flow model. In a rat AMI-reperfusion model, StemBells or ASCs were injected one week post-infarction. A pilot study demonstrated feasibility of intravenous StemBell injection, resulting in localization in ICAM-1-positive infarct area three hours post-injection. In a functional study five weeks after injection of StemBells cardiac function was significantly improved compared with controls, as monitored by 2D-echocardiography. This functional improvement neither coincided with a reduction in infarct size as determined by histochemical analysis, nor with a change in anti- and pro-inflammatory macrophages. In conclusion, the StemBell technique is a novel and feasible method, able to improve cardiac function post-AMI in rats., (Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.)

Introduction: Atrial fibrillation (AF) is a common complication in myocarditis. Atrial inflammation has been suggested to play an important role in the pathophysiology of AF. However, little is known about the occurrence of atrial inflammation in myocarditis patients. Here, we analyzed inflammatory cell numbers in the atria of myocarditis patients without symptomatic AF., Methods: Cardiac tissue was obtained postmortem from lymphocytic myocarditis patients (n=6), catecholamine-induced myocarditis patients (n=5), and control patients without pathological evidence of heart disease (n=5). Tissue sections of left and right ventricle and left and right atrium were stained for myeloperoxidase (neutrophilic granulocytes), CD45 (lymphocytes), and CD68 (macrophages). These cells were subsequently quantified in atrial and ventricular myocardium and atrial adipose tissue., Results: In lymphocytic myocarditis patients, a significant increase was observed for lymphocytes in the left atrial adipose tissue. In catecholamine-induced myocarditis patients, significant increases were found in the atria for all three inflammatory cell types. Infiltrating inflammatory cell numbers in the atrial myocardium correlated positively with those in the ventricles, especially in catecholamine-induced myocarditis patients., Conclusions: To a varying extent, atrial myocarditis occurs concurrently with ventricular myocarditis in patients diagnosed with myocarditis of different etiology. This provides a substrate that potentially predisposes myocarditis patients to the development of AF and subsequent complications such as sudden cardiac death and heart failure., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Background: Complement activation contributes significantly to inflammation-related damage in the heart after acute myocardial infarction. Knowledge on factors that regulate postinfraction complement activation is incomplete however. In this study, we investigated whether endogenous C1-inhibitor, a well-known inhibitor of complement activation, is expressed in the heart after acute myocardial infarction., Materials and Methods: C1-inhibitor and complement activation products C3d and C4d were analyzed immunohistochemically in the hearts of patients who died at different time intervals after acute myocardial infarction (n=28) and of control patients (n=8). To determine putative local C1-inhibitor production, cardiac transcript levels of the C1-inhibitor-encoding gene serping1 were determined in rats after induction of acute myocardial infarction (microarray). Additionally, C1-inhibitor expression was analyzed (fluorescence microscopy) in human endothelial cells and rat cardiomyoblasts in vitro., Results: C1-inhibitor was found predominantly in and on jeopardized cardiomyocytes in necrotic infarct cores between 12h and 5days old. C1-inhibitor protein expression coincided in time and colocalized with C3d and C4d. In the rat heart, serping1 transcript levels were increased from 2h up until 7days after acute myocardial infarction. Both endothelial cells and cardiomyoblasts showed increased intracellular expression of C1-inhibitor in response to ischemia in vitro (n=4)., Conclusions: These observations suggest that endogenous C1-inhibitor is likely involved in the regulation of complement activity in the myocardium following acute myocardial infarction. Observations in rat and in vitro suggest that C1-inhibitor is produced locally in the heart after acute myocardial infarction., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Background: Diagnosing lymphocytic myocarditis (LM) is challenging because of the large variation in clinical presentation and the limitations inherent in current diagnostic tools. The objective of this study was to analyze infiltration of inflammatory cells in quadriceps skeletal muscle of LM patients and investigate the potential diagnostic value of assaying infiltrating inflammatory cells., Methods: Quadriceps muscle tissue, obtained at autopsy from control patients (n = 9) and LM patients (n = 21), was analyzed using immunohistochemistry for infiltration of lymphocytes (CD45), macrophages (CD68), neutrophilic granulocytes (myeloperoxidase), and several lymphocyte subtypes (CD3, CD4, CD8, CD20) and using polymerase chain reaction for a panel of myocarditis-associated viruses. Additionally, quadriceps muscle from mice with acute coxsackievirus B3-induced myocarditis and control mice was analyzed for presence of lymphocytes and virus., Results: In quadriceps muscle of LM patients the number of infiltrating lymphocytes were significantly increased and LM was diagnosed with specificity of 100% and sensitivity of 71%. Parvovirus B19 was the primary virus found in our patient groups, found in quadriceps tissue of 3 LM patients (although it was also found in 1 control patient). In the mice, enteroviral RNA was present in the quadriceps muscle, although enteroviral capsid proteins and lymphocyte infiltration were found primarily in the adipose tissue within and directly adjacent to the myocyte tissue, rather than in the myocyte tissue itself., Conclusions: LM is associated with lymphocyte infiltration and viral presence in quadriceps muscle. This indicates that skeletal muscle biopsy/lymphocyte quantification might be a potential diagnostic tool for LM patients., (Copyright © 2014 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.)

Context: C1-esterase inhibitor (C1-inh) therapy is currently administered to patients with C1-inh deficiency through intravenous injections. The possibility of subcutaneous administration is currently being explored since this would alleviate need for hospitalization and increase mobility and well-being of patients. Recently, it was observed in pigs that C1-inh indeed can effectively be applied by subcutaneous injection. For studies on the effectiveness of C1-inh therapy for other indications than acquired and hereditary angioedema, rats are commonly used as model animal. For rats, however, subcutaneous C1-inh administration has never been investigated., Objective: To evaluate the efficacy of subcutaneous C1-inh administration in rats., Materials and Methods: Three boli of 100 U/kg human plasma-derived C1-inh were administered to Wistar rats on three consecutive days through subcutaneous injection or intravenous injection. Blood samples were collected from the tail veins 3, 4.5 or 6 h after C1-inh administration for measurement of C1-inh plasma levels. Antigen and activity levels of C1-inh of each plasma sample were determined by means of a specific ELISA., Results: For both C1-inh antigen and C1-inh activity, 21- to 119-fold higher plasma levels were measured after intravenous administration compared with subcutaneous administration. Subcutaneous administration also resulted in C1-inh plasma levels that were less stable and with decreased relative activity., Conclusion: These combined results indicate that in rats, subcutaneous injections in the present formulation are not effective as alternative administration route for C1-inh.

Serious abdominal injury as a result of a fall in a baby walker has not been previously reported. We present the case of a 13-month-old boy who developed intussusception following a fall down five stairs in a baby walker. Attempted hydrostatic reduction was unsuccessful. At operation, a bowel wall hematoma, serving as a lead point, was identified. This case adds another type of injury to the list of those previously associated with baby walker use.

Purpose: Fundoplication has been used successfully to treat gastroesophageal reflux in the pediatric population; however, the results are poorer in those children with neurological impairment. We propose an alternative approach to the needs of these special patients and report the use of esophagogastric disconnection to control reflux in children with profound neurological impairment., Methods: Between 1991 and 1997, 27 esohagogastric disconnections were performed. All patients were severely neurologically impaired with symptomatic gastroesophageal reflux confirmed by an upper gastrointestinal radiographic study. There were 16 boys and 11 girls with ages ranging from 6 months to 40 years. Three had undergone previous fundoplications that failed, whereas the remaining underwent esophagogastric disconnection as a primary antireflux procedure. Follow-up ranged from 1 month to 6.3 years (average, 2.8 years). The operative approach used a midline incision. The gastroesophageal junction was divided, and the gastric side was closed. A 30- to 40-cm jejunal limb was prepared for Roux-en-Y reconstruction and brought up to the esophagus in a retrocolic manner. Esophagojejunal and jejunojejunal anastomoses were then performed. A Stamm tube gastrostomy was placed, and the appendix was removed. A pyloroplasty and tube jejunostomy were performed when felt to be clinically indicated., Results: Gastroesophageal reflux symptoms resolved, and bolus feedings were tolerated by all patients. Oral feedings were tolerated except in those children limited by their swallowing abilities. Early postoperative complications occurred in eight patients (30%) with two (7%) requiring reoperation (esophageal leak and enterocolitis). Late reoperation was necessary in four patients (15%) for small bowel obstruction, paraesophagcal hernia, gastrostomy revision, and enterocolitis. There were no perioperative deaths, but three patients (11%) died of late surgical complications (two of small bowel obstructions, and one of improper reinsertion of a gastrostomy tube). Three other children died of unrelated causes., Conclusions: Esophagogastric disconnection effectively eliminates gastroesophageal reflux while allowing both bolus tube feedings and oral supplementation. This operation provides an alternative method of controlling gastroesophageal reflux in children with profound neurological impairment.

A study of 406 consecutive children operated upon for appendicitis from July 1982 to July 1987 was compared with a previously published study of 657 children with the same diagnosis operated upon between 1972 and 1982. This was done to determine if the methods of therapy continue to yield low complication rates and zero mortality rates. The routine use of antibiotic coverage for both aerobic and anaerobic bacteria in perforated appendicitis resulted in low complication rates, 3.2 per cent for major and 2.5 per cent for minor complications. Major complications included small intestinal obstruction and intra-abdominal abscess. Minor complications included wound infection and prolonged ileus. These rates are similar to those of the first investigation. The mortality rate continued to be zero. Complete peritoneal lavage was used in patients with generalized peritonitis or extensive localized peritonitis. Operative lysis of adhesions for small intestinal obstruction was required in four of these patients. This did not occur in patients with perforated appendicitis with abscess formation or more localized peritonitis who had no lavage. The technique rather than the disease process may be responsible for the complication.

The results of this study demonstrate that there is abnormal esophageal function in patients who have undergone repair of esophageal atresia. The diagnostic tests used may be too sensitive as the abnormalities demonstrated have little clinical relevance. In addition, there was an inverse relationship between signs and symptoms of esophageal dysfunction and the age of the child. The abnormalities are probably intrinsic and only secondarily affected by surgical treatment. Increased tension at the gastroesophageal junction is a likely factor in the production of gastroesophageal reflux. Esophageal dysfunction does not necessarily lead to detrimental gastroesophageal reflux with the sequela of repeated respiratory infections, failure to gain weight or esophageal stricture. Only patients who have such signs or symptoms need to undergo evaluation of esophageal function to determine if there is an abnormality. The results of the studies then document the need for an antireflux procedure.

Six hundred and fifty-one patients with appendicitis were reviewed and an over-all perforation rate of 36.5 per cent accompanied by a major complication rate of only 3.38 per cent and an over-all complication rate of 9.06 per cent was reported. This low complication rate despite a high level of perforation can be attributed to the use of antibiotic regimens effective against both aerobic and anaerobic organisms. A thorough irrigation and flushing of debris and exudate from the abdominal cavity of patients with ruptured appendicitis may improve these rates.

The return of stable premature infants to community hospitals from level III neonatal intensive care units is becoming more common. While these infants usually need only to gain weight, they are still at risk for significant neonatal problems. We report four cases of necrotizing enterocolitis (NEC) in nine stable, growing premature infants who weighed less than 1,300 g and returned to community hospitals. The onset of NEC was within 60 hours of transport, suggesting that transport and early feeding after transport may have been contributory to NEC.

Postoperative intussusception is a documented complication of pediatric surgical and pediatric urologic abdominal operations. In contrast to "primary" intussusception's triad of crampy abdominal pain, palpable abdominal mass, and "currant jelly" stools, postoperative intussusception is generally characterized by abdominal pain and vomiting. An abdominal mass is not usually palpable, and few children have bloody stools. Proper diagnosis and treatment may be delayed because of similar abdominal symptoms in children who may be receiving radiation and chemotherapy, or with prolonged ileus. Two children operated on for Wilms tumor demonstrate the need for awareness of this potential problem in the postoperative patient.

The initial pathologic diagnosis in an 11-month-old girl presenting with a suprarenal mass was true histiocytic lymphoma. The histiocytic nature of the cells was verified by ultrastructural, histochemical, and immunologic studies. The subsequent course featured widespread dissemination as both tumorous masses and diffuse tissue infiltrates, including extensive soft tissue, leptomeningeal, and bone marrow involvement, with a terminal histiomonocytic leukemic phase. Subsequently, this tumor was reclassified as malignant histiocytosis with atypical features, and this case exemplifies the difficulties in classifying some malignant histiomonocytic neoplasms. The overlapping clinical, pathologic, and theoretic features of true histiocytic lymphoma, malignant histiocytosis, and histiomonocytic leukemia are discussed in the context of this case.

The predominant electrolyte imbalance associated with enterourinary fistulas is hyperchloremic acidosis. The mechanism is the absorption of urinary electrolytes across the colonic mucosa. One of the genitourinary associated anomalies of a high imperforate anus is a rectourinary fistula. There have been 5 cases of hyperchloremic acidosis as a complication of an imperforate anus with a rectourinary fistula reported in the literature to date. An additional case is presented with a clinical analysis of the previously reported cases. The important factors in the development of hyperchloremic acidosis in patients with an imperforate anus are 1) the presence of a rectourinary fistula, 2) an initial diverting colostomy permitting a long segment of colonic mucosa for the absorption of urinary electrolytes, 3) distal urinary tract obstruction allowing significant volumes of urine to flow into the colonic segment and 4) the presence of urinary tract infection contributing to the urinary obstruction. Management should consist of vigorous electrolyte therapy, decreasing the retrograde flow of urine into the colon by temporary catheterization and early repair of the fistulous tract.

Two boys with acute urinary retention were found to have a persistent pelvic mass after bladder decompression. Evaluation in each disclosed a large pelvic abscess secondary to a ruptured appendix. The diagnosis of appendicitis may be difficult and appendiceal abscess presenting with acute urinary retention in children has been reported previously in only 7 instances. History, physical examination, laboratory studies, and radiographic and ultrasonic evaluations should lead to the correct diagnosis, and surgical intervention restores normal voiding.

Fifty-four neonates with necrotizing enterocolitis (NEC) were separated on basis of outcome. Of 35 factors compared between a high-risk and a low-risk group, only six were found to be statistically significant and useful in the development of a NEC score: number of days before beginning enteral feedings; blood pH; serum bicarbonate concentration; white blood cell differential; abdominal tenderness; and presence of portal vein gas. All laboratory values and physical and radiographic findings were from the initial presentation of NEC. Neonates with a score of 3 or more are at an increased risk of developing severe NEC with a greater than 50% mortality. The study suggests that enteral feedings should be withheld from neonates at risk of developing NEC for the first 12 days of life.

A 17-year-old male with Crohn's disease presented with persistent fever and right upper quadrant tenderness. Ultrasonography and abdominal computerized axial tomography (CAT scan) showed two large loculated abscess cavities in the right lobe of the liver. Surgical drainage and antibiotic therapy led to resolution of both cavities over a 5-month period. Unlike six previously reported patients, our patient had no evidence of pylephlebitis or mesenteric abscess formation at surgery. We speculate that his abscesses arose through seeding of mesenteric vessels and portal bacteremia.

Spontaneous, focal gastrointestinal perforation occurred in six very low birth weight infants. The first recognized clinical sign of perforation in five of the six infants was striking blue-black discoloration of the abdominal wall. In all cases the clinical and radiographic presentations, as well as the histologic findings, were distinct from those associated with necrotizing enterocolitis. All 4 infants who underwent exploratory laparotomy and repair had excellent surgical outcomes.

High resolution real-time ultrasound of two female infants showed normal ovaries located in the inguinal canal and demonstrated cysts within the solid ovarian tissue. As this appearance is quite distinct from that of the solid homogeneous testis, ultrasound can determine the nature of the gonad present.