Bacterial translocation as a source of Dacron-graft contamination in experimental aortic operation: the importance of controlling SIRS

Foregut Erosion Related to Biomedical Implants: A Scoping Review

Introduction: Biomedical devices implanted transabdominally have gained popularity over the past 50 years in the treatment of gastroesophageal reflux disease, paraesophageal hiatal hernia, and morbid obesity. Device-related foregut erosions (FEs) represent a challenging event that demands special attention owing to the potential of severe postoperative complications and death. Purpose: The aim was to provide an overview of full-thickness foregut injury leading to erosion associated with four types of biomedical devices. Methods: The study was conducted using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews (PRISMA-ScR). PubMed, EMBASE, and Web of Science databases were queried until December 31, 2023. Eligible studies included all articles reporting data, management, and outcomes on device-related FE. Results: Overall, 132 articless were included for a total of 1292 patients suffering from device-related FE. Four different devices were included: the Angelchik antireflux prosthesis (AAP) (n = 25), nonabsorbable mesh for crural repair (n = 60), adjustable gastric banding (n = 1156), and magnetic sphincter augmentation device (n = 51). The elapsed time from device implant to erosion ranged from 1 to 480 months. Most commonly reported symptoms were dysphagia and epigastric pain, while acute presentation was reported rarely and mainly for gastric banding. The technique for device removal evolved from more invasive open approaches toward minimally invasive and endoscopic techniques. Esophagectomy and gastrectomy were mostly reported for nonabsorbable mesh FE. Overall mortality was .17%. Conclusions: Device-related FE is rare but may occur many years after AAP, nonabsorbable mesh, adjustable gastric banding, and magnetic sphincter augmentation implant. FE-related mortality is infrequent, however, increased postoperative morbidity and the need for esophagogastric resection were observed for nonabsorbable mesh-reinforced cruroplasty.

Molsidomine alleviates acetic acid-induced colitis in rats by reducing oxidative stress, inflammation and apoptosis

Ulcerative colitis (UC) is a subcategory of intestinal inflammatory bowel disease characterized by up-regulation of proinflammatory cytokines and oxidative stress. The current study was designed to assess the probable protective effect of the nitric oxide (NO) donor, molsidomine, in experimental colitis model in rats. Rats were haphazardly classified into four groups: control, acetic acid, acetic acid + molsidomine (1 mg/kg) and acetic acid + molsidomine (2 mg/kg). Molsidomine (1 and 2 mg/kg/day) was administered by intra-peritoneal injection for 7 days prior to induction of UC. On the 8th day, colitis was induced by intra-rectal instillation of 2 ml of (4% v/v) acetic acid in normal saline using a pediatric plastic catheter. The rats were sacrificed 1 day following colitis induction, blood samples were obtained; colons and livers were isolated then underwent macroscopic, biochemical, histopathological and immunohistochemical examination. Pretreatment with molsidomine significantly reduced disease activity index, colon mass index, colonic macroscopic and histological damage. Besides, molsidomine significantly reduced the serum levels of alanine transaminase (ALT) (58.7 ± 8.9 & 59.7 ± 8 vs 288.75 ± 31.4 in AA group) and aspartate transaminase (AST) (196.2 ± 37.4 & 204 ± 30 vs 392.7 ± 35.6 in AA group). Moreover, molsidomine effectively decreased malondialdehyde (MDA) and total nitrate/nitrite (NOx) contents, and up regulated the enzymatic activity of superoxide dismutase (SOD) and glutathione level (GSH) in colonic and hepatic tissues. With regard to anti-inflammatory mechanisms, molsidomine suppressed tumor necrosis factor-alpha (TNF-α) (792.5 ± 16.7 & 448 ± 12.1 vs 1352.5 ± 45.8 in AA group) in colonic tissues and (701 ± 19 & 442.5 ± 22.5 vs 1501 ± 26 in AA group) in hepatic tissues as well as nuclear transcription factor kappa B (NF-kB/p65) levels (416.2 ± 4.1 & 185.5 ± 14.2 vs 659.2 ± 11.5 in AA group) in colonic tissues and (358 ± 6.2 & 163.5 ± 9.6 vs 732.5 ± 5.5 in AA group) in hepatic tissues. In addition, molsidomine significantly decreased inducible nitric oxide synthase (iNOS) levels (8.1 ± 0.1 & 4.9 ± 0.1 vs 16 ± 0.1 in AA group) in colonic tissues and (8.6 ± 0.3 & 6.1 ± 0.1 vs 17.8 ± 0.1 in AA group) in hepatic tissues, and myeloperoxidase (MPO) contents (10.5 ± 0.4 & 6.6 ± 0.3 vs 20.9 ± 0.6 in AA group) in colonic tissues and (13.1 ± 0.2 & 6.3 ± 0.06 vs 23.9 ± 1.4 in AA group) in hepatic tissues at p > 0.05. Furthermore, it suppressed apoptosis by reducing expression of Caspase 3 and Bax in colonic and hepatic tissues. Therefore, molsidomine might be a promising candidate for the treatment of UC.

Pulmonary Vasodilation by Intravenous Infusion of Organic Mononitrites Of 1,2-Propanediol in Acute Pulmonary Hypertension Induced by Aortic Cross Clamping and Reperfusion: A Comparison With Nitroglycerin in Anesthetized Pigs

INTRODUCTION

Suprarenal aortic cross clamping (SRACC) and reperfusion may cause acute pulmonary hypertension and multiple organ failure.

HYPOTHESIS

The organic mononitrites of 1,2-propanediol (PDNO), an nitric oxide donor with a very short half-life, are a more efficient pulmonary vasodilator and attenuator of end-organ damage and inflammation without significant side effects compared with nitroglycerin and inorganic nitrite in a porcine SRACC model.

METHODS

Anesthetized and instrumented domestic pigs were randomized to either of four IV infusions until the end of the experiment (n = 10 per group): saline (control), PDNO (45 nmol kg min), nitroglycerin (44 nmol kg min), or inorganic nitrite (a dose corresponding to PDNO). Thereafter, all animals were subjected to 90 min of SRACC and 10 h of reperfusion and protocolized resuscitation. Hemodynamic and respiratory variables as well as blood samples were collected and analysed.

RESULTS

During reperfusion, mean pulmonary arterial pressure and pulmonary vascular resistance were significantly lower, and stroke volume was significantly higher in the PDNO group compared with the control, nitroglycerin, and inorganic nitrite groups. In parallel, mean arterial pressure, arterial oxygenation, and fraction of methaemoglobin were similar in all groups. The serum concentration of creatinine and tumor necrosis factor alpha were lower in the PDNO group compared with the control group during reperfusion.

CONCLUSIONS

PDNO was an effective pulmonary vasodilator and appeared superior to nitroglycerin and inorganic nitrite, without causing significant systemic hypotension, impaired arterial oxygenation, or methaemoglobin formation in an animal model of SRACC and reperfusion. Also, PDNO may have kidney-protective effects and anti-inflammatory properties.

Current progress of research on intestinal bacterial translocation

Under normal conditions, the intestinal flora and the body are in dynamic equilibrium. When the barrier function of the intestinal tract is damaged due to various reasons, changes in the number and proportion of bacteria or spatial displacement result in bacterial translocation (BT), which ultimately leads to multiple organ dysfunction syndrome (MODS). Endogenous infections and endotoxemia caused by intestinal flora and endotoxin translocation are the origins of inflammatory responses, and the intestinal tract is the organ in which MODS both initiates and targets. Only by ensuring the integrity of the intestinal mucosal barrier can intestinal BT be effectively prevented. Elimination of the primary disease and maintaining blood and oxygen supply to the intestine is the most basic treatment. Early initiation of the intestinal tract, establishment of enteral nutrition, and selective digestive decontamination are also highly effective treatments. Early diagnosis, intervention, or prevention of BT may be a new avenue or important connection in the treatment of various diseases. The mechanism of BT, detection techniques, prevention and treatment, and its interaction with parenteral diseases were reviewed.

Cardiotrophin-1 attenuates experimental colitis in mice

Cardiotrophin-1 (CT-1) holds potent anti-inflammatory, cytoprotective, and anti-apoptotic effects in the liver, kidneys, and heart. In the present study, the role of endogenous CT-1 and the effect of exogenous CT-1 were evaluated in experimental ulcerative colitis. Colitis was induced in CT-1 knockout and wild-type (WT) mice by administration of dextran sulphate sodium (DSS) in the drinking water during 7 days. CT-1 knockout mice showed higher colon damage and disease severity than WT mice. In addition, CT-1 (200 µg/kg/day, iv) or vehicle (as control) was administered during 3 days to WT, colitic mice, starting on day 4 after initiation of DSS. Disease activity index (DAI), inflammatory markers (tumor necrosis factor α (TNF-α), INFγ, IL-17, IL-10, inducible nitric oxide synthase (iNOS)), colon damage, apoptosis (cleaved caspase 3), nuclear factor κB (NFκB) and STAT-3 activation, and bacterial translocation were measured. Compared with mice treated with DSS, mice also treated with exogenous CT-1 showed lower colon damage, DAI, plasma levels of TNFα, colon expression of TNF-α, INFγ, IL-17, iNOS and cleaved caspase 3, higher NFκB and signal transducer and activator of transcription 3 (STAT3) pathways activation, and absence of bacterial translocation. We conclude that endogenous CT-1 plays a role in the defense and repair response of the colon against ulcerative lesions through an anti-inflammatory and anti-apoptotic effect. Supplementation with exogenous CT-1 ameliorates disease symptoms, which opens a potentially new therapeutic strategy for ulcerative colitis.

The Influence of Carbon Dioxide Pneumoperitoneum on Systemic Inflammatory Response Syndrome and Bacterial Translocation in Patients With Bacterial Peritonitis Caused by Acute Appendicitis

OBJECTIVE

To explore the influence of carbon dioxide pneumoperitoneum (CDP) on system inflammatory response syndrome (SIRS) and bacterial translocation (BT) in patients with bacterial peritonitis (BP) caused by acute appendicitis (AA).

METHODS

Eighty-six consecutive subjects were randomly divided into the laparoscopy and laparotomy groups (n = 44 and n = 42, respectively). The levels of white blood cells (WBC), C-reactive protein (CRP), tumor necrosis factor α (TNF-α), and interleukin 6 (IL-6) of the 2 groups were tested preoperatively and at days 1, 2, and 4 after surgery. Blood and secretion culture was performed to verify whether septicemia or incision infection occurred, respectively. And the abdominal ultrasound or computed tomography scanning was used to diagnose peritoneal abscess for the suspected patients. The essential risk factors related to the aggravation of SIRS were analyzed through analysis of variance and binary logistic regression.

RESULTS

The postoperative blood levels of WBC, CRP, TNF-α, and IL-6 on day 4 in the laparoscopy group were significantly lower than those in the control group (all Ps < .05). The differences in incidence rates of septicemia and peritoneal abscess between the CDP and control groups were not statistically significant ( P > .05). Nevertheless, the incision infection rate in the laparoscopy group was apparently lower than that in the control group (4.55% vs 19.04%, P = .047). Analysis of variance and binary logistic regression showed that the non-pneumoperitoneum, pathological type of appendicitis, and multidrug resistant infections were the 3 major risk factors for SIRS (the P values were .001, .019, and .012, respectively).

CONCLUSION

It was found that CDP is safe for BP and could be a potential protective factor to mitigate BP effectively, indicating that the performance of laparoscopy operation under CDP is feasible to control SIRS; at the same time, CDP would not raise the incidence rate of BT.

Comparative study of bacterial translocation control with nitric oxide donors and COX2 inhibitor

OBJECTIVE AND DESIGN

To evaluate the beneficial effects of exogenous NO and an inhibitor of the COX2, and their action levels in a model of SIRS/bacterial translocation (BT) induced by Zymosan A(®).

MATERIAL AND METHODS

Ninety Wistar rats were submitted to different treatments, and after 12h and 24h they were anaesthetized in order to collect blood, mesenteric lymph nodes, and kidney for subsequent biochemical analyses and microbiological examinations.

TREATMENTS

A nitric oxide donor, Molsidomine(®), was compared with a COX2 inhibitor, Celecoxib(®).

METHODS

Zymosan A(®) was administered to Wistar rats. The animals were divided into 6 groups: one group for survival study, Group (1) No manipulation (BASAL); Group (2) vehicle of Zymosan A(®) given intraperitoneally (SHAM); Group I (control), with Zymosan A(®) (0.6g/kg) intraperitoneally; Group II (Molsidomine), with Molsidomine(®) (4mg/kg) through the penis dorsal vein, 30min prior to administration of the Zy(®) (0.6g/kg); Group III (Celecoxib), with Celecoxib(®) (400mg/kg) orally through a stomach tube, 6h prior to administration of the Zy (0.6g/kg).

DETERMINATIONS

The parameters survival, bacterial translocation, renal function, neutrophil accumulation, oxygen free radicals (OFR), detoxifying enzymes, and cytokines were measured at different times after Zymosan administration.

RESULTS

The model established induced a mortality rate of 100% and generated BT and systemic inflammatory response syndrome (SIRS) in all samples. It also significantly increased all variables, with p<.001 for MPO and all pro-inflammatory cytokines, and p<.01 for all OFR. Treatment with Molsidomine reduced mortality to 0%, decreased BT, MPO, pro-inflammatory cytokines and OFR (p<.001) significantly and increased IL-10 and IL-6 production. Moreover, the Celecoxib(®) showed a lower capacity for SIRS regulation.

CONCLUSIONS

The exogenous administration of NO prevented BT and controlled SIRS. Therefore these results suggest that Molsidomine could be used as a therapeutic strategy to protect against BT.

Surgery, wound healing, and metastasis: recent insights and clinical implications

BACKGROUND

Surgery-induced acceleration of tumour growth has been observed since several centuries.

METHODS

We reviewed recent insights from in vitro data, animal experimentation, and clinical studies on how surgery-induced wound healing or resection of a primary cancer influences the tumour-host ecosystem in patients harbouring minimal residual or metastatic disease.

RESULTS

Most of the growth factors, chemokines, and cytokines orchestrating surgical wound healing promote tumour growth, invasion, or angiogenesis. In addition, resection of a primary tumour may accelerate synchronous metastatic growth. In the clinical setting, indirect evidence supports the relevance of the above findings. Randomized clinical trials are underway comparing resection versus observation in metastatic breast and colon cancer with asymptomatic primary tumours.

CONCLUSIONS

In depth knowledge of how surgical intervention alters the tumour-host-metastasis communicating ecosystems could have important implications for clinical decision making in patients with synchronous metastatic disease and for the design and timing of multimodality treatment strategies.

Up-regulation of the Apo/Fas (CD95) complex on neutrophils harvested during cardiac surgery: distinct findings in patients operated on with or without the use of cardiopulmonary bypass

Aims: In a group of patients undergoing cardiac surgery performed both with (“on-pump”) and without the use (“offpump”) of cardiopulmonary bypass (CPB), we studied the changes of neutrophil membrane apoptosis-inducing complex Apo/Fas.

Methods: Expression of Apo/Fas (CD95) on leukocytes was evaluated by flow cytometry.

Results: In “on-pump” patients, we found an increase in the expression of CD95 median intensity fluorescence (MFI) on granulocytes from a baseline level median=56, (Q 1=45.5, Q3=64) to a median=88, (Q1=62, Q 3=109.5; p<0.01) at the 3rd postoperative day and median=74, (Q1=63, Q3=84.5; p<0.01) at the 7th postoperative day. In “off-pump” patients, granulocyte CD95 MFI was median=55, (Q1=51, Q3=84) before surgery. The significant increase was found on the 3rd postoperative day only; median=90, (Q 1=66; Q3=98; p<0.05). A similar pattern in the CD95 expression was also found if percentage changes of granulocyte CD95 MFI were followed. Moreover, the significantly increased Apo/Fas expression expressed as a percentage change of CD95 MFI was found in “on-pump” patients compared to “off-pump” patients, both at the 3rd postoperative day (p<0.05) and at the 7th postoperative day (p<0.01).

Conclusions: This is the first direct evidence of increasing densities of the Apo/Fas complex on neutrophils in cardiac surgical patients.

Mesenteric microcirculatory dysfunctions and translocation of indigenous bacteria in a rat model of strangulated small bowel obstruction

PURPOSE

Bacterial translocation has been shown to occur in critically ill patients after extensive trauma, shock, sepsis, or thermal injury. The present study investigates mesenteric microcirculatory dysfunctions, the bacterial translocation phenomenon, and hemodynamic/metabolic disturbances in a rat model of intestinal obstruction and ischemia.

METHODS

Anesthetized (pentobarbital 50 mg/kg, i.p.) male Wistar rats (250-350 g) were submitted to intestinal obstruction or laparotomy without intestinal obstruction (Sham) and were evaluated 24 hours later. Bacterial translocation was assessed by bacterial culture of the mesenteric lymph nodes (MLN), liver, spleen, and blood. Leukocyte-endothelial interactions in the mesenteric microcirculation were assessed by intravital microscopy, and P-selectin and intercellular adhesion molecule (ICAM)-1 expressions were quantified by immunohistochemistry. Hematocrit, blood gases, lactate, glucose, white blood cells, serum urea, creatinine, bilirubin, and hepatic enzymes were measured.

RESULTS

About 86% of intestinal obstruction rats presented positive cultures for E. coli in samples of the mesenteric lymph nodes, liver, and spleen, and 57% had positive hemocultures. In comparison to the Sham rats, intestinal obstruction induced neutrophilia and increased the number of rolling (approximately 2-fold), adherent (approximately 5-fold), and migrated leukocytes (approximately 11-fold); this increase was accompanied by an increased expression of P-selectin (approximately 2-fold) and intercellular adhesion molecule-1 (approximately 2-fold) in the mesenteric microcirculation. Intestinal obstruction rats exhibited decreased PaCO2, alkalosis, hyperlactatemia, and hyperglycemia, and increased blood potassium, hepatic enzyme activity, serum urea, creatinine, and bilirubin. A high mortality rate was observed after intestinal obstruction (83% at 72 h vs. 0% in Sham rats).

CONCLUSION

Intestinal obstruction and ischemia in rats is a relevant model for the in vivo study of mesenteric microcirculatory dysfunction and the occurrence of bacterial translocation. This model parallels the events implicated in multiple organ dysfunction (MOD) and death.

Emergency surgery of the abdominal aorta in a porcine model: two sequential experiments

The aim of this study was to design an aggressive nonlethal animal model that would simulate surgical treatment of the abdominal aorta with a view to studying the systemic inflammatory response. Fourteen pigs were subjected to two sequential experiments. Experiment A was performed to determine the response to two degrees of hemorrhage: (A1) 40% bleeding; and (A2) 60% bleeding over 15 minutes followed by midline laparotomy and aortic dissection. Experiment B included two methods of aortic repair: (B1) aortic resection and replacement with a prosthesis; and (B2) aortic bypass without aortic resection. In the latter two groups, suprarenal aortic cross-clamping was placed for 30 minutes after a 40% hemorrhage. We analyzed various inflammatory markers and mortality. The 40% bleeding (vs. 60%) elicited a smaller decrease in mean arterial pressure (110 +/- 6 vs. 89 +/- 9 mmHg) but did not cause irreversible shock or mortality. After the 40% hemorrhage, the B1 aortic repair caused two cases of paraplegia. We have developed a model to study the combined effect of bleeding and aortic cross-clamping.