Comparison of electromagnetic field stimulation on the healing of small and large intestinal anastomoses

Nayci, Ali/0000-0002-0534-1205WOS: 000170453000023PubMed: 11535860PURPOSE: Magnetic fields have been shown to affect biologic processes. Accordingly, an experimental study was designed to investigate the effect of electromagnetic field stimulation on intestinal healing and to compare small and large intestinal anastomoses. METHODS: An ileal or a colonic anastomosis was constructed in rats. Beginning the day after surgery, randomly assigned groups were exposed to sinusoidal electromagnetic field stimulation of 10.76-mT intensity and 50-Hz frequency, with 2-hour-on/10-hour-off cycles. After seven days, intestinal anastomoses were assessed for hydroxyproline content and breaking strength. Statistical comparison between each experimental and control group yielded significance (P g/mg (P = 0.0249) and in colon from 1.526 +/- 0.11 to 1.922 +/- 0.11 mug/mg (P = 0.0135). Breaking strength also increased significantly in ileum from 0.213 +/- 0.01 to 0.255 +/- 0.01 MPa (P = 0.001) and in colon from 0.227 +/- 0.01 to 0.270 +/- 0.01 MPa (P = 0.006). CONCLUSIONS: Electromagnetic field stimulation provided a significant gain in anastomotic healing in both small and large intestine. There were no apparent differences detected between the healing of small and large intestinal anastomoses except for slight differences in the tune sequences of events and magnitude. The study demonstrated a significant increase in both biochemical and mechanical parameters. Additional investigations are needed to determine optimal conditions and promote selective biologic responses

The role of the spleen on colonic anastomotic healing

Comelekoglu, Ulku/0000-0001-8060-6333; Nayci, Ali/0000-0002-0534-1205WOS: 000184490200007PubMed: 12893499The role of the spleen on wound healing remains unclear. This study investigates the effect of splenectomy on the healing of colonic anastomoses. Twenty-six Wistar rats were assigned into four groups: sham, splenectomy, anastomoses, and splenectomy and anastomoses. The rats underwent a standardized left colonic resection and primary anastomoses, and/or splenectomy. Bursting pressure and hydroxyproline content were used to evaluate anastomotic healing, five days postoperatively. No differences were found in the bursting pressure and hydroxyproline content between the groups. The present results indicate that splenectomy has no negative effect on the healing of colonic anastomoses in rats

Effect of electromagnetic fields and early postoperative 5-fluorouracil on the healing of colonic anastomoses

Nayci, Ali/0000-0002-0534-1205WOS: 000181357100008PubMed: 12548416Background and aims: Studies have indicated a deleterious effect of perioperative 5-fluorouracil (5-FU) administration on the healing of intestinal anastomoses. This study examined the effect of early postoperative 5-FU on the healing of colonic anastomoses and investigated the effect of electromagnetic fields (EMF) on colonic anastomotic repair under normal physiological conditions and in the presence of 5-FU therapy in a rat model. Materials and methods: Forty male Wistar rats were randomly assigned into four groups and underwent a standardized left colonic resection and anastomoses. The animals then served as control or received intraperitoneal 5-FU (20 mg/kg per day, 5 days), EMF stimulation (10.76 mT, 50 Hz; 2-h on/10-h off cycles, 7 days) or both, starting on the day of surgery. After 7 days anastomotic healing was assessed by measurement of hydroxyproline content and breaking strength. Results: Hydroxyproline content increased in EMF exposed group (1.53+/-0.11 to 1.92+/-0.11 mug/mg) and in EMF + 5-FU group (1.53+/-0.11 to 1.89+/-0.12 mug/mg). Breaking strength also increased in the EMF group (0.23+/-0.02 to 0.27+/-0.01 MPa) and in the EMF + 5-FU group (0.23+/-0.02 to 0.28+/-0.01 MPa. No differences were found in hydroxyproline content or breaking strength between the 5-FU group and controls. Conclusion: Early postoperative 5-FU administration did not impair the healing of colonic anastomoses in rats. Additionally, EMF stimulation provided a significant gain in colonic anastomotic strength, in rat intestines in control animals and in animals exposed to 5-FU

Intestinal ischemia-reperfusion induced diaphragm contractility dysfunction: Electrophysiological and ultrastructural study in a neonatal rat model

PubMedID: 26411723Aim To evaluate the remote effect of intestinal ischemia reperfusion (IR) injury mediated by tumor necrosis factor alpha (TNF-?) on diaphragm contractility functions and whether administration of NAC may counteract the possible detrimental effects in an experimental neonatal rat model. Methods 40 Wistar rat pups were randomized into four groups; ten animals in each. Intestinal ischemia was conducted by obstructing mesentery of intestines by a silk loop. In the control group; only laparotomy was performed. After 1 h ischemia, reperfusion was conducted for 1 h in 1 h group, 24 h for 24 h group and 24 h for 24 h + NAC group but administration of NAC (150 mg/kg/day) intraperitoneally twice a day was performed. Inflammatory response was evaluated by tissue TNF-? level and contractility functions by mechanic activity studies of the diaphragm. Electrophysiology of the diaphragm and the phrenic nerve was conducted to determine neuropathy or myopathy and transmission electron microscopy was performed to evaluate ultrastructural changes in the phrenic nerve. Results Diaphragm tissue TNF-? level significantly increased in 1 h and 24 h groups (P = 0.004, P = 0.0001; respectively). Diaphragm mechanic activation force and duration significantly decreased at 1 h and 24 h (P = 0.004, P = 0.02 and P = 0.0001, P = 0.0001; respectively). NAC administration significantly prevented decrease in the maximal contraction and the duration (P < 0.001). Phrenic nerve compound action potential (CMAP) amplitude significantly decreased in 1 h group (P < 0.0001) and NAC administration significantly prevented this decrease when compared with 24 h group (P < 0.001). In diaphragmatic needle electromyography, the duration of motor unit potentials (MUP) was prolonged significantly when compared with control group. Contractility and electrophysiological studies were indicating primarily neuropathy in diaphragm dysfunction. Histopathology revealed axonal and myelin degeneration in the 1 h and 24 h group, but less injury in the NAC administered group. Conclusions Intestinal IR induced elevation of TNF-? level in the diaphragm. Impairment in the diaphragm contractility and neuropathic changes in the phrenic nerve occurred even in the first hour of reperfusion. NAC administration prevented these detrimental effects. © 2016 Elsevier Inc. All rights reserved

Trapidil, an inhibitor for phosphodiesterase and platelet-derived-growth factor, ameliorates corrosive esophageal burn in rats

WOS: 000232286600004PubMed: 16210831Corrosive esophageal burn is a common health problem in the pediatric age group and causes serious esophageal injuries. The medical treatment In acute phase of corrosive esophageal injury is of particular importance for prevention of esophageal stricture. We therefore aimed to investigate the possible beneficial effect of trapidil (triazolopyrimidine), an inhibitor for phosphodiesterase and platelet-derived-growth-factor, during acute phase of esophageal corrosive injury. Wistar albino rats were randomly allocated to untreated, treated, and sham-operated groups (n = 10 for each group). Corrosive esophageal burn was generated with 10% NaOH solution. The rats were left untreated (untreated group) or treated with trapidil as a single dose of 40 mg/kg intraperitoneally after one hour of the injury (treated group). Abdominal esophageal segment was isolated and tied in sham-control group. The studied esophageal segment was removed from each animal after 24 hours. Malondialdehyde (MDA) and nitric oxide (NO) levels were measured in the esophageal tissues. The ulcer depth was graded by histopathologic examination. MDA and NO levels were significantly higher in the untreated group than in the treated group. Namely, trapidil treatment significantly decreased MDA and NO levels in the injured tissues, the levels of which are similar to those in the tissues of control animals. The grades of ulcer depth were significantly improved in the treated group. These results indicate that the reactive oxygen radicals increase in the early phase of corrosive esophagitis and cause tissue damage. We suggest that trapidil treatment may be useful in acute phase of corrosive esophageal injury