Combination effect of melatonin and dexamethasone on liver ischemia/reperfusion injury

OBJECTIVE

Liver failure following ischemia-reperfusion (I/R) injury is a major concern in liver surgery. The purpose of this study was to evaluate combination pretreatment with melatonin (MEL) and dexamethasone (DEX) on liver I/R model. Male Wistar rats (n = 60) were assigned to 5 groups of 12 animals each: (1) Sham: laparotomy without I/R; (2) I/R: hepatic I/R; (3) I/R+MEL: hepatic I/R+melatonin injected intraperitoneally (20 mg/kg); (4) I/R+DEX: hepatic I/R+ dexamethasone injected intravenously (10 mg/kg); (5) I/R+MEL+DEX: hepatic I/R+ melatonin injected intraperitoneally+dexamethasone injected intravenously. The liver was subjected to ischemia by clamping the portal triad for 30 minutes and then reperfused for 6 hours after ischemia by removing the clamps.

RESULTS

The levels of glutathione peroxidase (GPx) and superoxide dismutase (SOD) decreased after hepatic I/R in all groups. Levels of GPx and SOD were higher in I/R+MEL+DEX group compared to I/R, I/R+MEL and I/R+DEX groups and they were significantly higher in I/R+MEL group compared to I/R and I/R+DEX groups (p < 0.05). Levels of ALT, AST, TNF-α, hepatic tissue malondialdehyde (MDA), liver injury index, and apoptotic index increased after hepatic I/R. Levels of ALT, AST, tissue MDA, tissue injury index and apoptotic index were lower in I/R+MEL+DEX group compared to those in I/R, I/R+MEL and I/R+DEX groups, and in I/R+MEL they were significantly lower than in I/R+DEX group (p < 0.05). TNF-α level was lower in I/R+MEL+DEX group compared to other groups and it was significantly lower in I/R+DEX group than in I/R+MEL and I/R groups (p < 0.05).

CONCLUSION

Combination therapy with melatonin and dexamethasone had better results in decreasing the liver injury compared to when each of them was administered alone (Tab. 3, Ref. 58).

Repeated small bowel resection in a patient with Buerger's disease and intestinal involvement

Buerger's disease, also called thromboangiitis obliterans, is a recurrent and an uncommon vaso-occlusive inflammatory disease, which typically affects small and medium-sized arteries, veins and nerves of the upper and lower extremities. Mesenteric and multisystem involvement of two or more organs is extremely rare. Here we report the case of a 39-year-old male heavy smoker who had undergone four repetitive laparotomies and multiple small bowel resections for ischaemic involvement of Buerger's disease. He had below-the-knee amputation of the right leg and finger of the left hand because of that disease before bowel involvement. Histopathological findings revealed that the arteries and veins of the resected small intestine were occluded with organised thrombi. Inflammatory cell infiltration was recognised mainly in the intima of distal branches of mesenteric artery. These findings were compatible with previous findings in histopathological examinations of amputated extremities.

Schwannoma of stomach

Gastrointestinal mesenchymal tumours are a group of tumours originating from the mesenchymal stem cells of the gastrointestinal (GI) tract. Digestive tract Schwannomas are rare mesenchymal tumours occurring most frequently in the stomach. We report the case of a 40-year-old woman with gastric Schwannoma located at the posterior wall of the antrum.

Scalpel blade changer

Surgical knife has been extensively used in surgery for a number of years and is the most widely used surgical instrument in the world at present. Manual removal of the blade can be difficult, particularly when the scalpel is wet. Percutaneous injuries during changing the scalpel blade may lead to serious and potentially fatal infections from blood borne pathogens such as hepatitis B virus (HBV), hepatitis C (HCV), or human immunodeficiency virus (HIV) and others including cytomegalovirus, herpes simplex virus and parvovirus B19. In addition to the risk of illness and death after an exposure, psychological trauma and long-term disability are of great concern. Many devices have been developed in an effort to facilitate the removal of the blade from the scalpel, and to render the removal procedure less dangerous. But there is no device to both remove and install the blade at the same time. In particular, the present invention relates to a scalpel blade changer that enables a blade to be removed from a scalpel and retained in the remover and at the same time to install the blade on to the scalpel handle.

Lipoic acid prevents hepatic and intestinal damage induced by obstruction of the common bile duct in rats

INTRODUCTION

Cholestatic liver diseases are characterized by impaired hepatocellular secretion of bile, resulting in intracellular accumulation of bile acids which result in a shift in the oxidant/prooxidant balance in favor of increased free radical activity and injury of different tissues including liver and intestine. The aim of this research was to study protective effect of lipoic acid (LA) as a potent antioxidant in cholestsis induced hepatic and intestinal injury in rats.

MATERIALS AND METHODS

Forty five adult male Wistar rats were randomly assigned to four groups each containing fifteen rats as follows: sham operation (SO) (control), bile duct ligating (BDL), and BDL+LA (25 mg/kg). After fourteen days hepatic and intestinal tissue sampled and blood serum sampled for pathologic and biochemical studies.

RESULTS

Levels of SOD and GPx antioxidant enzymes were higher in BDL+LA group comparing to BDL group, levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST) and γ-glutamyltranspeptidase (GGT), and pathologic scores in liver and intestine were lower in BDL+LA group comparing to BDL group significantly, but there is no significant difference in concentrations of total bilirubin between groups.

CONCLUSIONS

Our results showed the protective potential of LA with liver and intestine damage. Despite improvements in operative technique and the development of potent, broad-spectrum antibiotics, biliary tract surgery in patients with obstructive jaundice is still associated with high morbidity and mortality rates In summary, our results show that BDL induced hepatic and intestinal injury were significantly attenuated by LA administration and the administration of LA could effectively diminish this damage.

Erythropoietin ameliorates oxidative stress and tissue injury following renal ischemia/reperfusion in rat kidney and lung

OBJECTIVE

To study the effect of erythropoietin (EPO) treatment on renal and lung injury following renal ischemia/reperfusion (I/R).

MATERIALS AND METHODS

Thirty male Wistar rats were assigned to three groups of 10 rats each. The first group was sham-operated, the second was subjected to renal I/R (30 min of ischemia followed by 24 h of reperfusion). The third group was subjected to renal I/R and treated with EPO in two doses: the first dose 1 h prior to ischemia (1,000 U/kg) and the second dose 6 h after ischemia (1,000 U/kg).

RESULTS

The renal and lung tissue injury index, tissue serum blood urea nitrogen and creatinine (Cr) were higher in the renal I/R group compared to the renal I/R + EPO group; the difference was statistically significant (p < 0.05). Kidney and lung tissue glutathione peroxidase and superoxide dismutase levels were higher in the renal I/R + EPO group than the renal I/R group; the difference was also statistically significant (p < 0.05).

CONCLUSION

The data showed that EPO pretreatment could be effective in reducing renal and lung injury following renal I/R and could improve the cellular antioxidant defense system. Hence EPO pretreatment may be effective for attenuating renal and lung injury after renal I/R-induced injury during surgical procedures, hypotension, renal transplantation and other conditions inducing renal I/R.

Improving hepatitis B vaccine efficacy in end-stage renal diseases patients and role of adjuvants

Hepatitis B virus (HBV) infection is a serious global health problem.The prevalence of viral hepatitis is higher in dialysis patients than in the general population because of the opportunity for exposure during the dialysis procedure. Immunization is the most effective way to prevent transmission of hepatitis B virus (HBV) and hence the development of acute or chronic hepatitis B. It is well established that patients with end-stage renal disease including dialysis-dependent patients, have an impaired immune response to hepatitis B vaccine. End stage renal diseases (ESRD) patients have lower seroconversion rates compared with the subjects with intact renal function. Moreover, even after the completion of vaccination schedule anti-hepatitis B (anti-HBs) titers of responder dialysis, patients are low and decline logarithmically with time. The impaired efficacy of HBV vaccine in patients with ESRD has been attributed to numerous factors such as immune compromise because of uremia and some other factors. One approach to improve the immunogenicity of existing HBV vaccines is adjuvantation, and it's very important to find more effective adjutants for improving HBV vaccine efficacy. In this paper we have a brief review on recently known new ways for improving HBV vaccine efficacy.

Comparison of 5 IU and 10 IU tuberculin test results in patients on chronic dialysis

Immunocompromised patients such as those with end-stage kidney failure under-going hemodialysis (HD) are at increased risk of developing tuberculosis (TB). For this reason, routine TB screening of HD patients with tuberculin test has been recommended. The Center for Disease Control and Prevention (CDC) has recommended that patients with chronic renal failure should undergo annual skin testing for TB with tuberculin [purified protein derivative (PPD)], with an induration of ≥10 mm at 48 h depicting a positive reaction. The aim of this study was to compare the results of two different doses of PPD in dialysis patients. This descriptive and comparative multicenter study was performed on 255 patients on chronic dialysis in Tabriz, Iran. These patients did not have the PPD test done within the preceding one year. Patients were divided into two groups randomly and conventional or double-dose tuberculin test was performed using the Mantoux technique with 5 IU (group 1) and 10 IU (group 2) of PPD. Results were interpreted 48-72 h after injection. Patients were divided into those with less than 10 mm and those with ≥10 mm duration. Mean age was 44.6 ± 15 years (M/F = 1.5/1). The mean duration on dialysis was 39 ± 7 months. There was no significant difference regarding the age, gender, dura-tion on dialysis, causes of chronic kidney disease, erythrocyte sedimentation rate, C-reactive protein and serum albumin between the two groups. The mean induration was 4.6 mm and 7.7 mm in groups 1 and 2, respectively. There was induration ≥10 mm in 19.6% and 25.5% of group 1 and 2, respectively, which showed a significant difference (P <0.05). In conclusion, because of the high frequency of TB in dialysis patients, an annual tuberculin test may be recommended. Our study showed that the double-dose tuberculin test may be a better substitute to the conventional test in dialysis patients.

Fracture of the alumina-bearing couple delta ceramic liner

The fracture rate of third-generation ceramic liners is greatly reduced compared with first- and second-generation liners because of improvements in the design and manufacturing process. Fractures of the alumina-bearing couple are rare for the same reason.This article describes a case of a fracture of an alumina-bearing couple delta ceramic liner without trauma history that was treated with ceramic-on-polyethylene revision total hip arthroplasty. A 57-year-old man was admitted to the hip ward because of an alumina-bearing couple delta ceramic liner fracture. He underwent hip replacement by anterior approach 18 months previously in the same center because of left hip primary osteoarthritis. He received a 54×36-mm modular press-fit cup ceramic alumina-bearing couple delta insert. Probable causes of such fractures are manufacture production failure and edge loading based on cup inclination, but in our patient, inacceptable range of motion, failure of the locking mechanism during implantation insertion, or cracking were possible causes of fracture.Although the fracture rate of third-generation alumina-bearing couples is low, we believe that it may not be possible to eliminate the actual risk of alumina head fracture. Patients should be informed about the potential for this complication before receiving an alumina-bearing couple.

Oxidative effect of methotrexate administration in spinal cord of rabbits

OBJECTIVE

To study the potential effect of Methotrexate (MTX) on lipid peroxidation and activity of glutathione peroxidase (GPx) and superoxide dismutase (SOD) two important endogenous anti-oxidant enzymes.

METHODS

Twenty healthy male Newzland rabbits weighting 1500-1800 g were divided into two groups. One group was considered as the MTX groups and the other was considered as control group. Rabbits had free access to food and tap water. Rabbits in MTX group received a single dose of MTX, 20 mg/kg intraperitoneally, a similar volume of saline was administered to control group. After 6 days rabbits were uteinized and spinal tissue excised for biochemical studies.

RESULTS

GPX and SOD activities in spinal tissue in rabbits of MTX group significantly reduced after MTX administration compared to control group(P = 0.002 vs 0.18). An increase in the tissue MDA level was seen in the MTX group, suggesting increased lipid peroxidation. Levels of MDA were significantly higher in MTX group compared to control group (P = 0.002).

CONCLUSION

Our data suggests that MTX treatment induces oxidative tissue damage on the spinal tissue, as assessed by increased lipid peroxidation and decreased GPX and SOD levels, so decreasing oxidative stress by anti-oxidant agents may play a key role in attenuating spinal cord injury.

Ameliorating effects of dexpanthenol in cerebral ischaemia reperfusion induced injury in rat brain

OBJECTIVE

To study the attenuating effect of Dexpanthenol (Dxp) provitamin B5 on neuronal damage after cerebral ischaemia/reperfusion.

METHODS

This was a randomized, controlled experimental study conducted at the Islamic Azad University, Tabriz, Iran, from April to September 2008. Male wistar rats were divided into 4 groups randomly (n=13): 1- sham group, Group 2 :two hours occlusion of middle cerebral artery (MCA) and 24 hours reperfusion. Group 3: two hours occlusion of MCA and 24 hours reperfusion + Dxp (250mg/kg) since 3 days before ischaemia. Group 4: two hours occlusion of MCA and 24 hours reperfusion which had received Dxp (500mg/kg) since 3 days before ischaemia. Glutathione (GSH) and malondialdehyde (MDA) levels were studied in brain tissue and numbers of cornu ammonis (CA1 and CA3) pyramidal neurons were studied with light microscopy.

RESULTS

The GSH levels were significantly higher in groups 3 and 4 as compared with group 2. In group 3 and group 4 animals, the MDA levels were significantly lower than in group 2 (P < 0.05). Numbers of CA1 and CA3 neurons were completely normal in appearance in the group 1. The surviving neurons in the CA1 and CA3 subfield were markedly decreased in number, in group 2 (P < 0.05).

CONCLUSION

Our pathologic and biochemical study has proven positive effect of Dxp on protection of cerebral tissue after I/R. The present findings correlate with previous studies on the protective effects of Dxp against cell and tissue injury by I/R.

Protective effect of pentoxyfilline in renal toxicity after methotrexate administration

INTRODUCTION

Nephrotoxicity is an important side-effect of treatment with Methotrexate (MTX). Pentoxifylline (PTX) is an anti-inflmmatory and anti-oxidant agent. We hypothesized that pentoxifylline may affords renal protection by downregulating TNF-alpha as well as by improving cellular anti-oxidant activity.

MATERIALS AND METHODS

Forty five male Wistar rats were assigned to 3 groups of 15 animals each: Group 1: control group (0.9% saline). Group 2: MTX; injected with 20 mg/kg MTX intraperitoneally (i.p.). Group 3: MTX + PTX injected i.p. MTX (20 mg/kg) + PTX (50 mg/kg) i.p. PTX was administered since 3 days before MTX administration and continued for 6 days. After 6 days rats were anesthetized and serum sampled and renal tissue removed for biochemical and histological evaluation.

RESULTS

Data showed that glutathione peroxidase (GPx), superoxide dismutase (SOD) activities were lower in PTX + MTX group comparing to MTX group significantly (p < 0.05). Renal tissue injury index and percent of TUNEL positive cells, renal tissue malondialdehyde (MDA) levels, serum BUN (Blood Urea Nitrogen), creatinine (Cr) and TNF-alpha levels were higher in MTX group comparing to MTX+PTX group significantly (p < 0.05).

CONCLUSIONS

In this study, the increased level of tissue MDA and serum TNF-alpha level together may be suggested that the underlying mechanism is related to direct toxicity of MTX rather than blockage in folate synthesis in kidneys. PTX administration also attenuated renal tissue injury and number of apoptic cells and suppressed the elevation of BUN and Cr levels. However, further studies are essential to elucidate the exact mechanisms of MTX-induced renal toxicity, and protection and the effect of PTX.

Scalpel safety and new scalpel blade remover

Percutaneous injuries to surgical staff carry a reciprocal risk for patients, with potential for infection transmission from provider to patient. The operating room is the highest-risk setting for this mode of transmission because open wounds are susceptible to contamination, and injury to the hands of surgical staff resulting in bleeding is not uncommon. The traditional scalpel (surgical knife) has been extensively used in surgery for a number of years and would be the most widely used surgical instrument in the world at present. A conventional surgical scalpel comprises a reusable, sterile handle having a tang at one end on which a replaceable slotted blade is mounted. The handle is intended to be used repeatedly, but the blade is normally discarded after each instance of use. Removal devices are designed to protect the user and downstream staff from accidental injury when removing a scalpel blade from a reusable handle. Passing tray and single-handed scalpel blade remover. It is a primary object of the present invention (Patent No. 62851- 40294) to reduce or substantially eliminate the risk of changing scalpel blades. It is a further object of the present invention to simplify the removal of a scalpel blade from its handle.

Evaluation of Copper, Zinc, Cu/Zn, and VEGF in Patients with AML in Iran

BACKGROUND

Copper and zinc are the elements with numerous physiological activities. Copper (Cu) has an important role in angiogenesis and acts by increasing Vascular Endothelial Growth Factor (VEGF). Serum levels of copper will be increased in cancer incidence, progression and recurrence. The aim of this study was to measure blood levels of copper, zinc, and the ratio of Cu /Zn, as well as VEGF levels before and after treatment of acute myeloid leukemia.

METHODS

Thirty patients who were recently diagnosed with Acute Myeloblastic Leukemia (AML) in Shahid Ghazi Tabatabai oncology hospital enrolled in this clinical trial. On the first day, blood samples were taken for copper, zinc, and VEGF assay and flowcytometry. Treatment protocol was (7×3) regimen. Blood samples were collected for evaluation of copper, zinc, and VEGF. They were sent to Biochemistry Laboratory in medicine faculty for analysis.

RESULTS

Amongst 30 AML patients, 14 (46.7%) were female and 16 (53.3%) were male. Patients of various ages ranged from 16 to 53 years, with a median age of 9.1±9.35 years. The mean serum level of copper, zinc, and mean Cu/Zn ratio before and after treatment showed significant difference (p<0.05) There was also significant difference between the mean VEGF level before and after treatment (p<0.05).

CONCLUSION

This study reveals that there is no significant relationship between copper, zinc serum levels, their ratio, and VEGF in AML patients. We hypothesize that increased serum copper is associated with increase of VEGF levels which can indicate the impact of copper in malignancies including AML.

Anti-oxidative effect of lipoic Acid in spinal cord ischemia/reperfusion

OBJECTIVE

Lipoic acid (LA) is an effective anti-oxidant agent that can scavenge free radicals in biological systems. The aim of this research was to study the probable protective effect of LA in spinal ischemic/reperfusion (I/R) injury.

MATERIALS AND METHODS

Thirty male Wistar rats, weighing 230-285 g, were assigned randomly into 3 groups (10 animals in each group): sham spinal I/R, and spinal I/R + LA. The spinal I/R + LA rats received LA 100 mg/kg subcutaneously 3 days prior to ischemia induction and 3 days after. The induction of ischemia lasted for 30 min.

RESULTS

At 72 h postoperatively, the neurological status was worse in the I/R group than the sham group (p < 0.05). The neurological status of animals in the LA-treated group appeared better than the I/R group (p < 0.05). In the I/R group, tissue glutathione peroxidase (GPx) and super oxide dismutase (SOD) activity were significantly less compared to the control group (p < 0.05). In the LA-treated group, tissue GPx and SOD levels were higher compared to the I/R group (p < 0.05).

CONCLUSIONS

LA pretreatment reduced neurologic injury in the rats, most probably by maintaining the oxidant/anti-oxidant ion balance during spinal cord ischemia. Reperfusion may have contributed to the protective effects seen in the LA pretreatment.

Are Doppler ultrasonography parameters symmetric between the right and left kidney?

Background:

Among numerous modalities applied for evaluation of kidney diseases, Doppler ultrasonography (DU) provides information about the hemodynamic status of the kidneys. Meanwhile, the variability in DU parameters of the right and left kidney is a matter of controversy. The aim of this study was to determine whether any difference exists between the DU indices of the right and left kidney.

Methods:

Retrospectively, we collected DU findings of 25 healthy potential renal transplant donors. All donors underwent renal DU and multidetector computed tomographic angiography before donor nephrectomy. DU indices, including peak systolic volume (PSV), resistive index (RI), pulsatility index (PI), end-diastolic volume (EDV), and acceleration time (AT), were recorded.

Results:

The median age of the donors was 27 (range 23–39) years. The median PSV, RI, EDV, and AT for the right kidney were 29 cm/sec, 0.59, 10.9 cm/sec, and 50 msec, respectively. For the left kidney, the median PSV, RI, EDV, and AT were, respectively, 26.8 cm/sec, 0.60, 10.6 cm/sec, and 43 msec. Among the DU indices, median PI of the right kidney was significantly different from that of the left kidney (1.02 versus 0.95, P = 0.01).

Conclusion:

In conclusion, the present study revealed that right kidney DU indices, except for PI, may not differ from those of the left kidney.

Simvastatin attenuates intestinal ischemia/reperfusion induced injury in rat

Ischaemia/reperfusion (I/R) injury is commonly seen in the field of intestine surgical interventions, shock, trauma, and many other clinical conditions. Simvastatin is known to have antioxidant and anti-inflammatory properties. This study investigated the effect of simvastatin administration in a warm intestinal I/R model on TNF-alpha, antioxidant enzymes and intestinal tissue morphology. Thirty-six male wistar rats underwent laparotomy under general anaesthesia. Simvastatin was administered from four days before ischaemia induction. The rats were divided in to three groups (n = 12): the sham group, the I/R group, and the I/R + simvastatin group. Intestinal ischaemia was induced by superior mesenteric artery ligation with microvascular clamps for 60 minutes, and after ischaemia, blood perfusion was released into the tissue and a reperfusion phase was started, which lasted for 3 hours. After 3 hours, the animals were sacrificed and serum and tissue obtained for biochemical and histological study. In the simvastatin treated group, intestinal tissue injury, TNF-alpha level, and tissue malondealdehyde levels were significantly lower than in the I/R group (p < 0.05). Glutathion peroxidase and superoxide dismutase levels were significantly higher in the simvastatin treated group than in the I/R group (p < 0.05). Simvastatin pretreatment reduced intestinal I/R injury and was associated with down- -regulation of serum TNF-alpha and tissue malondealdehyde level, and simvastatin administration maintained cellular antioxidant enzyme contents compared to the I/R group after 3 hours reperfusion time.

Simvastatin decreases hepatic ischaemia/reperfusion-induced liver and lung injury in rats

Liver failure is still a significant clinical problem after transplantation surgery, tissue resections (the Pringle manoeuvre) and haemorrhagic shock. The restoration of blood flow to an ischaemic region leads to tissue injury at a greater rate than the original ischaemic insult, an event termed "ischaemia-reperfusion injury" (I/R). Despite advances in surgical techniques, I/R still poses a problem of clinical importance. In this research, we studied the effect of simvastatin pretreatment on liver and lung injury induced by hepatic I/R. Rats were subjected to 30 min of ischaemia followed by 24 h of reperfusion. Simvastatin (10 mg/kg) was administered orally from three days before the operation. After the reperfusion time, serum ALT, AST, LDH and TNF a levels were studied and liver and lung tissues were stained with haematoxylin and eosin and TUNEL to detect apoptotic cells. Serum aminotransferase activity and LDH and TNFalpha levels were increased markedly by hepatic I/R, and these were suppressed significantly by simvastatin. The tissue injury index and the number of apoptotic cells via TUNEL staining in the liver and lungs were higher in the I/R group than in the I/R + simvastatin group. These results suggest that simvastatin ameliorates I/R-induced liver and lung tissue damage by inhibiting the level of inflammation and the apoptotic pathways. Simvastatin administration may therefore provide protection against the adverse effects of I/R injury in liver transplantation.