Oya Evirgen

The phrenico-esophageal ligament: an anatomical study

The phrenico-esophageal ligament (PEL), which is claimed by some to be an important anti-reflux barrier, has been accepted as an important structure by some surgeons dealing with the surgical treatment of hiatal hernias. However, the characteristics of its anatomical structure and the physiological importance of this ligament is still a subject of discussion. The aim of this study was to define this anatomic structure and to point out the clinical importance of the PEL. This study has been carried out on samples taken from 2 fresh and 12 fixed cadavers. The PEL was observed to be derived from the transversalis and endothoracic fascia attaching the esophagus to the diaphragmatic crura at the region of the esophageal hiatus. While the transversalis fascia covered the inferior surface of the diaphragm, it was observed to divide into upper and lower leaflets when it approached the esophageal hiatus. The endothoracic fascia turned superiorly at the level of esophageal hiatus and attached on to the esophagus by uniting with the upper leaflet of the transversalis fascia in 11 of the specimens. In three of the specimens, it attached on the esophagus at a higher level than the transversalis fascia. The histologic sections of our study revealed that the PEL is formed by collagen and elastic fibers composed of fibroblasts and blood vessels. Since the PEL is a strong structure that firmly attached to the esophageal wall and surrounded the upper part of the distal esophagus like a skirt, it is reasonable that it may play an important role in the gastroesophageal sphincteric mechanism. Histological evidence for decrease in collagen fibers with age and the loose arrangement of the elastic fibers due to this decrement might decrease the resistance and the elasticity of the PEL. This situation may explain the predisposition to hiatal hernias seen with increased in age.

Does Decorin Protect Neuronal Tissue via Its Antioxidant and Antiinflammatory Activity from Traumatic Brain Injury: An Experimental Study.

BACKGROUND The development of secondary brain injury via oxidative stress after traumatic brain injury (TBI) is well known. Decorin (DC) inactivates transforming growth factor β1, complement system, and tumor necrosis factor α, which are related to oxidative stress and apoptosis. Consequently, the aim of the present study was to evaluate the role of DC on TBI. METHODS A total of 24 male rats were used and divided into 4 groups as follows; control, trauma, DC, and methylprednisolone (MP). The trauma, DC, and MP groups were subjected to closed-head contusive weight-drop injuries. Rats received treatment with intraperitoneal saline, DC, or MP, respectively. All the animals were killed at the 24th hour after trauma and brain tissues were extracted. The oxidant/antioxidant parameters (malondialdehyde, glutathione peroxidase, superoxide dismutase, and NO) and caspase 3 in the cerebral tissue were analyzed, and histomorphologic evaluation of the cerebral tissue was performed. RESULTS Levels of malondialdehyde, NO, and activity of caspase 3 were significantly reduced, and in addition glutathione peroxidase and superoxide dismutase levels were increased in the DC and MP groups compared with the trauma group. The pathology scores and the percentage of degenerated neurons were statistically lower in the DC and MP groups than in the trauma group. CONCLUSIONS The results of the present study showed that DC inactivates transforming growth factor β1 and protects the brain tissue and neuronal cells after TBI.

Therapeutic evaluation of interleukin 1-beta antagonist Anakinra against traumatic brain injury in rats

BACKGROUND The aim of this study was to evaluate the therapeutic efficiency of Anakinra, an IL-1ß antagonist with anti-inflammatory effects, in an experimental model of traumatic brain injury (TBI). METHODS Fifty-four rats underwent TBI after a weighted object was dropped onto a metal disc secured to their skulls. Animals were randomized into 3 main groups: control (n=18), TBI + saline (n=18; six animals per time-point) with samples obtained at the first, sixth and twenty-fourth h postoperatively, and TBI + Anakinra (n=18; six animals per time-point) with brain samples obtained at the first, sixth and twenty-fourth h postoperatively. Brain tissue and blood serum were extracted for the analysis of IL-1ß, malondialdehyde, glutathione peroxidase, superoxide dismutase, and catalase levels. Tissue sections were evaluated histopathologically under a light microscope. RESULTS After trauma, tissue and serum IL-1ß levels were significantly elevated and after Anakinra administration, these levels substantially decreased. Glutathione peroxidase, superoxide dismutase, and catalase activity decreased following TBI and Anakinra administration proved effective in increasing the activity of these antioxidant enzymes. Histopathological analysis confirmed that Anakinra might protect the brain tissue and nerve cells from injury. CONCLUSION Results demonstrate that Anakinra reduces the development of inflammation and tissue injury events associated with TBI.

The faith of ilioinguinal nerve after preserving, cutting, or ligating it: an experimental study of mesh placement on inguinal floor.

BACKGROUND Postherniorrhaphy chronic pain may be related to the trauma to the regional nerves or prosthetic mesh. This study was aimed to search the objective findings of prosthetic mesh placement on the ilioinguinal nerve in three different nerve treatment patterns with two different mesh types. MATERIALS AND METHODS Thirty New Zealand rabbits were used. Bilateral ilioinguinal nerves were identified. A 2×1 cm standard polypropylene mesh was laid on the nerve on right side, whereas a same sized lightweight polypropylene was applied on the left after three different nerve treatments were carried out. The nerve was completely preserved in the first group [G1], cut by scissors without a further process in the second [G2], and proximal cut end was ligated with 5/0 polyglactin. Three months after the surgery, bilateral nerve samples were taken from the contiguous nerve segment for light microscopy and electron microscopy. RESULTS Nerve protection could not prevent microscopic changes entirely. Prosthetic mesh itself seemed to cause histopathologic changes. Overall incidence of histopathologic changes in light microscopy, without taking the nerve treatment pattern into account, was somewhat lower at standard mesh side than that of lightweight mesh side. However this difference did not reach the level of significance (P=0.39). When three groups were evaluated in respect to overall nerve damage without paying attention to mesh type, the highest damage rate was observed in G3 (cut and ligate). When each group was compared separately within itself for histopathologic changes, no differences were observed between heavy and light mesh sides in any group. When the microscopic changes were compared in respect to the different nerve treatment patterns on heavyweight mesh side, the rates were 12.5%, 12.5%, and 33.3%, respectively. On lightweight mesh side, all three groups exhibited similar microscopic finding rates, 37.5%, 25.0%, and 33.3%, respectively. Protection of the nerve resulted in virtually zero neuroma formation after two types of mesh use. Surgical trauma to the nerve was observed to have an obvious potential for neuroma formation. Mesh type did not affect the overall neuroma rate within the whole subject pool; both groups displayed same 40% overall neuroma development rate. The neuroma incidence was in 43.8% G2 and 72.2% in G3, however the difference did not attain level of significance (P=0.09). The highest rate was observed when a lightweight mesh was used after dividing and ligating the nerve. CONCLUSIONS Light mesh could not provide a protection in subjects whose nerves were injured during surgery. Ligation of the cut end of the nerve also could not be helpful. Nerve protection still seems to be the best way for a nerve-related complaint-free postoperative period. The merit of nerve end implantation into the muscle should also be reconsidered.

Fibrin Sealant Effects on the Ilioinguinal Nerve

ABSTRACT Background: Chronic pain after mesh repair for inguinal hernia may be related to the trauma to the regional nerves by direct compression with sutures, staples, or tacks during mesh fixation. Fibrin sealant (FS) has been recommended to eliminate this risk. In this experimental study, the effects of FS on the ilioinguinal nerve when a mesh was applied was searched. Materials and Methods: Fifteen New Zealand rabbits were used in three groups. In Group 1, a 2×1 cm, standard monofilament, pure polypropylene mesh was laid over ilioinguinal nerve. In Group 2, 0.5 ml FS was applied on the nerve without using an onlay mesh. In Group 3, a 2×1 cm mesh was laid onlay and secured with 0.5 ml FS with no fixating suture. Three months after surgery bilateral nerve samples were taken from the contiguous nerve segment for microscopic study. Results: Group 1 showed prominent findings with regard to all parameters. There were significant differences between Group 1 and Group 2 in respect of fibrosis, lymphocyte, and edema scores, and foreignbody reaction. The values of Group 3, where the mesh was secured by the application of FS with no suture, were roughly placed in between Group 1 and Group 2. Prominent fibrosis and increased collagen proliferation in peripheral area of mesh was seen in Group 1 subjects, whereas a mild fibroblastic activity among mesh fibers in Group 3 subjects. Conclusions: FS has no negative effect on ilioinguinal nerve. FS application may protect the nerve from the harmful effects of polypropylene mesh in inguinal hernia repair.

Potential neuroprotective effect of Anakinra in spinal cord injury in an in vivo experimental animal model

Objective: To evaluate the therapeutic effects of inhibiting interleukin-1 beta (IL-1β) in vivo using Anakinra in an experimental model of spinal cord injury (SCI). Methods: All experimental procedures were performed in the animal laboratory of Ankara Education and Research Hospital, Ankara, Turkey between August 2012 and May 2014. The SCI was induced by applying vascular clips to the dura via a 4-level T5-T8 laminectomy. Fifty-four rats were randomized into the following groups: controls (n = 18), SCI + saline (n = 18), and SCI + Anakinra (n = 18). Spinal cord samples were obtained from animals in both SCI groups at one, 6, and 24 hours after surgery (n = 6 for each time point). Spinal cord tissue and serum were extracted, and the levels of IL-1β, malondialdehyde, glutathione peroxidase, superoxide dismutase, and catalase were analyzed. Furthermore, histopathological evaluation of the tissues was performed. Results: The SCI in rats caused severe injury characterized by edema, neutrophil infiltration, and cytokine production followed by recruitment of other inflammatory cells, lipid peroxidation, and increased oxidative stress. After SCI, tissue and serum IL-1β levels were significantly increased, but were significantly decreased by Anakinra administration. Following trauma, glutathione peroxidase, superoxide dismutase, and catalase levels were decreased; however, Anakinra increased the activity of these antioxidant enzymes. Malondialdehyde levels were increased after trauma, but were unaffected by Anakinra. Histopathological analysis showed that Anakinra effectively protected the spinal cord tissue from injury. Conclusion: Treatment with Anakinra reduces inflammation and other tissue injury events associated with SCI.

The histopathological and ultrastructural effects of the topical application of bacitracin on the cerebral cortex in rats.

AIM Bacitracin is one of the most frequently used agents for the topical irrigation of the cerebral cortex. The aim of this study is to investigate whether bacitracin has histopathological and ultrastructural effects when applied topically to the cerebral cortex. MATERIAL AND METHODS Twenty-eight rats were randomly assigned to four groups. Except the control group, each rat underwent left frontoparietal craniectomy with dural removal. Then, in the sham group a piece of dry absorbable gelatin sponge was placed over the left hemisphere; in the saline group a gelatin sponge soaked in normal saline; and in the bacitracin group a gelatin sponge soaked in 500 units bacitracin was used. After 48 hours, brain tissues were extracted for histopathological and electron microscopic analyses. RESULTS Among the four groups dark stained neurons were found to be statistically higher in number in the bacitracin group compared with the control, sham and saline groups. Electron microscopic evaluation revealed that, in the bacitracin group, almost all cytoplasmic organelles were poorly preserved. CONCLUSION Topical application of the bacitracin on to the cerebral cortex caused histopathological and ultrastructural changes in the neural tissue. These changes may be an evidence for the neurotoxic effects of bacitracin.

The Protective effect of Omeprazole Against Traumatic Brain Injury: An Experimental Study

BACKGROUND The development of secondary brain injury via oxidative stress after traumatic brain injury (TBI) is a well-known entity. Consequently, the aim of the present study was to evaluate the role of omeprazole (OM) on rat model of TBI. METHODS A total of 24 male rats were used and divided into 4 groups as follows; control, trauma, OM, and methylprednisolone (MP). The trauma, OM, and MP groups were subjected to closed-head contusive weight-drop injuries. Rats received treatment with saline, OM, or MP, respectively. All the animals were sacrificed at 24 hours after trauma and brain tissues were extracted. The oxidant/antioxidant parameters (malondialdehyde, glutathione peroxidase, superoxide dismutase, nitric oxide) and caspase-3 in the cerebral tissue were analyzed, and histomorphologic evaluation of the cerebral tissue was performed. RESULTS Levels of MDA and activity of caspase-3 were significantly reduced in the OM and MP groups compared with the trauma group. Glutathione peroxidase and superoxide dismutase levels were increased both in the OM and MP groups compared with the trauma group. The pathology scores were statistically lower in the OM and MP groups than the trauma group. CONCLUSIONS The results of the present study showed that OM was as effective as MP in protecting brain from oxidative stress, and apoptosis in the early phase of TBI.

Stereologic and ultrastructural comparison of human and rat amniotic membrane wrapping for rat sciatic nerve repair

In this study we aimed to examine the effects on wound healing and nerve regeneration of human and rat amniotic membrane wraps around primary epineural anastomosis areas after a peripheral nerve transection injury in rats. We randomized 25 male adult rats with induced peripheral transection injuries into 5 groups (control, transection injury, primary epineural anastomosis [PEA] after injury, PEA with a human amniotic membrane [hAM] wrap, and PEA with a rat amniotic membrane [rAM] wrap groups and treated their injuries accordingly. We took tissue samples from the anastomosis regions, 12 weeks after the experiment, and analyzed them stereologically and ultrastructurally. We performed a statistical analysis with the recovered stereological counts and the measurement data. Our results showed that the use of amniotic membranes for allografts (between same species) instead of xenografts (between different species), along with microsurgery, provides a suitable microenvironment during the healing process with less immunological reaction on the injured site and supports axonal regeneration.

The effect of intra-articular levobupivacaine on shoulder cartilage at different doses - experimental study

BACKGROUND AND OBJECTIVES In this study it was aimed to examine the histological and morphometric effects on cartilage structure of intra-articular application of levobupivacaine to the shoulder joint. METHODS In twenty New Zealand adult male rabbits, 35 shoulders were used for the study and prepared in 5 groups of 7. These groups were defined as Groups L1, L2, L3 and L4 which were right shoulders administered with 0.25% and 0.5% levobupivacaine, Group C which were left shoulders as the control group and Groups S1 and S2 which were left shoulders administered with 0.9% saline. On the 2nd and 15th days the animals were killed, the glenohumeral joints were evaluated macroscopically then cartilage samples were taken. These samples were evaluated with Mankin score, and histomorphometrically by measuring the thickness of the cartilage between the superficial cartilage layer and the tidemark and the thickness of calcified cartilage between the tidemark and the subchondral bone. RESULTS Macroscopically, on the 15th day the joint fluid was seen to have reduced in all the groups. After microscopic evaluation, the highest Mankin score (mean: 3.14±2.1/14) was in the L4 group (15th day 0.5% levobupivacaine) and was found to be statistically significant (p<0.05). No statistically significant difference was determined between the other groups. CONCLUSIONS Histologically, as the highest Mankin score was in the L4 group, this indicates that in a single intra-articular injection of levobupivacaine a low concentration should be selected. LEVEL OF EVIDENCE Level 5, animal study.