Mesenteric lymph reperfusion may exacerbate brain injury in a rat model of superior mesenteric artery occlusion shock

BACKGROUND：The intestinal lymphatic pathway and intestinal ischemia/reperfusion are mainly involved in mesenteric lymph duct ligation or drainage; moreover,intervention by reducing the lymph liquid reflux might relieve lung and other organ dysfunction induced by intestinal ischemia/reperfusion; however,research addressing mesenteric lymph reperfusion （MLR） and brain injury has not yet to be reported.OBJECTIVE：To observe the effect of MLR on brain tissue in a rat model of superior mesenteric artery occlusion （SMAO） shock,and to explore the molecular mechanism of MLR.DESIGN,TIME AND SETTING：A randomized,controlled,animal experiment at a neuro-pathophysiology level was performed at the Institute of Microcirculation,Hebei North University; Department of Pathophysiology,Basic Medical College; Department of Pathology,the First Hospital of Hebei North University between December 2007 and March 2009.MATERIALS：Adenosine triphosphate （ATP） standard was provided by the National Institute for the Control of Pharmaceutical and Biological Products; lactic acid （LA）,superoxide dismutase （SOD）,malonaldehyde （MDA）,nitrogen monoxidum （NO）,nitric oxide synthase （NOS）,myeloperoxidase （MPO） and ATPase assay kits were provided by Nanjing Jiancheng Bioengineering Institute,China.METHODS：A total of 24 male Wistar rats were randomly divided into four groups.In the sham-surgery group （n = 6）,both the mesenteric lymph duct and the superior mesenteric artery were not blocked; in the MLR group （n = 6）,the mesenteric lymph duct was occluded for 1 hour followed by 2-hour reperfusion; in the SMAO group （n = 6）,the superior mesenteric artery was occluded for 1 hour followed by 2-hour reperfusion; in the MLR ＋ SMAO group （n = 6）,both the mesenteric lymph duct and superior mesenteric artery were occluded for 1 hour followed by 2-hour reperfusion.MAIN OUTCOME MEASURES：Mean arterial blood pressure prior to and following ischemia/reperfusion; brain tissue morphology levels of LA,MDA,SOD,NO,NOS,MPO,ATPase and ATP following reperfusion.RESULTS：MLR did not cause changes in mean arterial blood pressure,brain tissue morphology,LA,MDA,NO,ATP,SOD,NOS,MPO and ATPase.However,SMAO caused a rapid decrease and gradual increase of mean arterial blood pressure.Neuronal necrosis,degeneration and swelling were observed in brain tissue.Contents of MDA,NO,LA and ATP as well as activities of NOS and MPO were significantly increased （P〈 0.05）,but activities of SOD and Na＋-K＋-ATPase were significantly decreased （P 〈 0.05）.MLR aggravated neuronal damage in a rat model of SMAO shock.Following MLR,mean arterial blood pressure was significantly decreased （P 〈 0.05）,contents of MDA and NO as well as activities of NOS and MPO were significantly increased （P 〈0.05）,but activities of Ca2＋-ATPase,Mg2＋-ATPase and Ca2＋-Mg2＋-ATPase as well as ATP content were significantly decreased （P〈 0.05）.CONCLUSION：MLR aggravates brain injury in a rat model of SMAO shock,which correlates with oxygen-derived free radical injury,NO synthesis and release,sequestration of neutrophilic granulocytes,decreasing activity of cell membrane pumps and energy metabolism dysfunction.Pathogenesis of the intestinal lymphatic pathway should be thoroughly investigated to prevent ischemia/reperfusion injury.

Influence of mesenteric lymph reperfusion on neurotransmitter expression in brain tissue of a superior mesenteric artery occlusion shock rat model

BACKGROUND： Previous studies have shown that mesenteric lymph reperfusion （MLR） exacerbates brain injury in a rat model of superior mesenteric artery occlusion （SMAO） shock. However, little is known about the influence of MLR on neurotransmitter expression in brain tissue. OBJECTIVE： To observe the effect of MLR on brain tissue injury by measuring monoamine and cholinergic neurotransmitter levels. DESIGN, TIME AND SETTING： A randomized, controlled, animal experiment was performed at the Institute of Microcirculation, Hebei North University, China; Research Room of Microcirculation and Laboratory of Biochemistry, Department of Pathophysiology, Basic Medical College, Hebei North University between December 2007 and March 2009. MATERIALS： Choline acetyltransferase （CHAT） and acetylcholine esterase （ACHE） kits were provided by Nanjing Jiancheng Bioengineering Institute, China; dopamine （DA） and noradrenalin （NE） standards were provided by the National Institute for the Control of Pharmaceutical and Biological Products; HP1100 chromatograph of liquid was provided by Agllent, USA. METHODS： A total of 24 male, Wistar rats were randomly assigned to 4 groups： sham-surgery, MLR SMAO, and MLR ＋ SMAO groups, with 6 rats in each group. In the MLR or SMAO groups, the mesenteric lymph duct or superior mesenteric artery was blocked for 1 hour. In the MLR ＋ SMAO group, the mesenteric lymph duct and superior mesenteric artery were occluded for 1 hour, followed by 2-hour repeffusion. ChAT and AChE levels were measured using the synthesized and hydrolyzed acetylcholine method, respectively. Liquid chromatography was employed to quantitatively analyze DA and NE levels, using relative retention time and the external standard method. MAIN OUTCOME MEASURES： CHAT, ACHE, DA, and NE levels. RESULTS： AChE levels were significantly increased, but ChAT levels were significantly decreased in the MLR and MLR ＋ SMAO groups following 2-hour repeffusion （P〈 0.01）. However, AChE activity in the MLR ＋ SMAO group was greater than in the MLR group （P 〈 0.05）. DA and NE levels were significantly decreased in the SMAO and MLR ＋ SMAO groups （P〈 0.01）, while DA levels in the MLR ＋ SMAO group were less than in the SMAO group （P 〈 0.05）. CONCLUSION： MLR exacerbated brain injury in a rat model of SMAO shock, which correlated with the intestinal lymphatic pathway. MLR decreased DA levels, but increased AChE activity, in a rat model of SMAO shock.

Endoscopy-based early enterostomy closure for superior mesenteric arterial occlusion

AIM:To evaluate the efficacy of endoscopic examination of blood flow and edema in the remnant bowel.METHODS:We retrospectively studied 15 patients who underwent massive bowel resection with enterostomy for superior mesenteric arterial occlusion (SMAO); the patients were divided into a delayed closure group (D group) and an early closure group (E group).RESULTS:The mean duration from initial operation to enterostomy closure was significantly shorter in the E group (18.3 ± 2.1 d) than in the D group (34.3 ± 5.9 d) (P < 0.0001). The duration of hospitalization after surgery was significantly shorter in the E group (33 ± 2.2 d) than in the D group (51 ± 8.9 d) (P < 0.0002).CONCLUSION:Endoscopic examination of blood flow and edema in the remnant bowel is useful to assess the feasibility of early closure of enterostomy in SMAO cases.

Superior mesenteric vein thrombosis induced by influenza infection:A case report

BACKGROUND Among the various types and causes of mesenteric ischemia,superior mesenteric vein(SMV)thrombosis is a rare and ambiguous disease.If a patient presents with SMV thrombosis,past medical history should be reviewed,and the patient should be screened for underlying disease.SMV thrombosis may also occur due to systemic infection.In this report,we describe a case of SMV thrombosis complicated by influenza B infection.CASE SUMMARY A 64-year-old male visited the hospital with general weakness,muscle aches,fever,and abdominal pain.The patient underwent computed tomography(CT)and was diagnosed with SMV thrombosis.Since the patient’s muscle pain and fever could not be explained by the SMV thrombosis,the clinician performed a test for influenza,which produced a positive result for influenza B.The patient had a thrombus in the SMV only,with no invasion of the portal or splenic veins,and was clinically stable.Anticoagulation treatment was prescribed without surgery or other procedures.The follow-up CT scan showed improvement,and the patient was subsequently discharged with continued oral anticoagulant treatment.CONCLUSION This case provides evidence that influenza may be a possible risk factor for SMV thrombosis.If unexplained abdominal pain is accompanied by an influenza infection,examination of an abdominal CT scan may be necessary to screen for possible SMV thrombosis.

Arterial complication of irreversible electroporation procedure for locally advanced pancreatic cancer

Irreversible electroporation(IRE) is a non-thermal ablation technique used especially in locally advanced pancreatic carcinomas that are considered surgically unresectable.We present the first case of acute superior mesenteric artery(SMA) occlusion secondary to pancreatic IRE procedure that has not been reported before in the literature.A 66-year-old man underwent neoadjuvant chemoradiotherapy for locally advanced pancreatic ductal adenocarcinoma.IRE procedure was applied to the patient during laparotomy under general anesthesia.After finishing the procedure,an acute intestinal ischemia was detected.A conventional vascular angiography was performed and a metallic stent was successfully placed to the SMA and blood flow was maintained.It is important to be careful in such cases of tumor involvement of SMA when evaluating for IRE procedure of pancreatic tumor.

Enterocolic phlebitis:a rare cause of bowel ischemia and review of the literature

Enterocolic phlebitis(EP)is a rare cause of bowel ischemia due to isolated venulitis of the bowel wall and mesentery without arterial involvement.EP is often misdiagnosed as inflammatory bowel disease,carcinoma,or diverticulitis due to non-specific symptoms as well as non-specific clinical and radiologicalfindings.While unresponsive to pharmacotherapy,surgical resection of the affected bowel appears to be the only successful therapy with a very low recurrence rate.Etiology of EP remains unknown.We report a case of EP with rare presentation in the left hemicolon and unusual histologicalfindings emphasizing the heterogeneity of this cause of enterocolic ischemia.The review and comparison of the three enti-ties—EP,mesenteric inflammatory veno-occlusive disease(MIVOD),and idiopathic myointimal hyperplasia of mesenteric veins(IMHMV),all describing patterns of bowel ischemia due to isolated pathology of mesenteric veins—reveal that the current terminology is unclear.EP and MIVOD are very similar and may be considered the same disease.IMHMV,though,differs in localization,symptom duration,and histologicalfindings but also shares features with EP and MIVOD.Further studies and harmonized terminology are inevitable for better understanding of the disease,prevention of unnecessary pharmacotherapy,and reduction in time to diagnosis.