The reversing effect of ondansetron on bupivacaine-induced sciatic nerve block.

Background and Aims: This experimental study was designed to test the hypothesis that ondansetron, a selective 5-HT3 receptor antagonist, would decrease the duration of motor, sensory, and proprioception blockade in a dose-dependent fashion in a bupivacaine-induced sciatic nerve blockade. Materials and Methods: Forty-nine male Wistar Albino rats who underwent unilateral sciatic nerve block were divided into seven groups with an equal number in each group. Group B: only perineural block (PB), Group BO200: PB and perineural 200 µg ondansetron, Group BO400: PB and perineural 400 µg ondansetron, Group BO800: PB and perineural 800 µg ondansetron, Group BO800IP: PB and intraperitoneal 800 µg ondansetron, Group O800: only perineural 800 µg ondansetron, Group S: sham-operated. The rats' motor, sensory, and proprioception functions were evaluated by a blinded investigator every 10 min until they returned to normal function. The recovery times of the motor, sensory, and proprioception functions were recorded and compared. All sciatic nerves were removed and examined by electron microscopy for neurotoxic signs. Results: In which sciatic nerve block was formed with bupivacaine, the duration of the motor, sensory, and proprioception functions blockade was decreased, and the duration to return to normal functions was significantly shortened at Group BO800 (p < 0.05). According to electron microscopy results, perineural 200 µg, 400 µg, and 800 µg ondansetron were not neurotoxic. Conclusion: This is the first study showing that perineural ondansetron administration (800 µg dose) reverses the effect of the local anesthetics and shortens the duration of the motor, sensory, and proprioception functions blockade.

Revisiting the relationship between the submandibular duct, lingual nerve and hypoglossal nerve.

BACKGROUND: The aim of the study was to evaluate the relations between submandibular duct, lingual nerve and hypoglossal nerve for making a reassessment of this area in fresh frozen specimens. Also, the distance between the angle of the mandible and the vertical line drawn from the point where submandibular duct crossed lingual nerve to the base of the mandible was measured to determine a new landmark for neck surgeons. MATERIALS AND METHODS: Fourteen fresh frozen head and neck specimens were dissected and evaluated. A marginal mandibular incision was made from the mastoid process to the chin. RESULTS: In 8 cases, lingual nerve was crossing the submandibular duct superiorly; in 5 cases, lingual nerve was crossing the duct infero-medially and in 1 case it was parallel to the duct. In 1 case, lingual nerve subdivided into anterior and posterior branches. In 2 cases, 2 parallel submandibular ducts were found and the lingual nerve was crossing the upper duct from superior. In 1 case, lingual nerve was crossing the duct infero-medially and then it was subdividing into branches superior to mylohyoid. In 12 cases, the course of hypoglossal nerve was classical. In 1 case, hypoglossal nerve crossed the submandibular duct medially and coursed parallel to the tendon of posterior belly of digastric. And in another case, hypoglossal nerve crossed the inferior branch of submandibular duct medially. The other structures in this area were as usual. CONCLUSIONS: The main factor for reducing nerve damage during surgery is the understanding of the anatomy of this area.

Morphology of cranial sutures and radiologic evaluation of the variations of intersutural bones.

BACKGROUND: As far as our literature searches showed us, morphological characteristics of cranium such as sutures, sutural bones and fontanelles had been examined in the skulls in the museums and dry specimens until now. As a modern method, three-dimensional virtual reconstruction of cranial bones by using multidetector computed tomography-computed tomography angiography (MDCT-CTA) can display in vivo morphological characteristics. In our study, we aimed to determine the presence and incidence of these morphological characteristics that can be clinically significant in our population, by using radiologic methods. MATERIALS AND METHODS: We examined head and neck regions of 185 patients via MDCT-CTA. We evaluated radiologically detectable variations of the metopic sutures, lambda, bregma, asterion and pterion, which can be very easily confused with fractures. Additionally, the differences between the genders and incidence of coexistence of these variations were evaluated. RESULTS: According to our study, the incidence of persistent metopic suture was 8.1% and the incidence of lambda variations was 5.9%. Variations were most commonly encountered on the left asterion, and least commonly on the bregma and left pterion. In the evaluation of the coexistence of the parameters and combinations, the Wormian bones located at the right and left asterions were detected. There were no statistically significant differences between genders. CONCLUSIONS: Variations of the sutures and sutural bones can be easily misdiagnosed with the fractures of related bony regions in unconscious patients with multiple traumas. During surgical interventions in these patients, surgeons must take this fact into consideration in order to make differential diagnosis of fractures and intersutural bone variations.

Quantitative analysis of the terminal branches of facial nerve in fresh frozen head and neck specimens.

BACKGROUND: The first aim of this study was the quantification of nerve fibres found in terminal branches of facial nerve and the second aim was the ultrastructural analysis of these terminal branches in order to observe their ultrastructural differences, if present. In the examination of literature; we could not find any studies related to this subject. MATERIALS AND METHODS: Four fresh frozen head and neck specimens were used and the dissections were done bilaterally. Therefore; totally 8 samples were examined. The samples were prepared according to routine transmission electron microscopic tissue preparation technique. The semi-thin sections were examined under light microscope by camera lucida. In every sample, the quantitative analysis was performed in 5 different areas in an area of 0.01 mm2 and statistical analysis was done. Secondly; the ultrastructural appearance of these terminal branches were examined under transmission electron microscope. RESULTS: In the quantitative analysis of terminal branches of facial nerve in an area of 0.01 mm2; the least number of nerve fibres were found in temporal branches and the highest number were detected in cervical branches. In transmission electron microscopic examination, no significant difference was found in between these branches. In the statistical analysis; statistically significant differences were obtained in between the temporal and buccal, marginal mandibular, cervical branches; zygomatic and marginal mandibular, cervical branches; buccal and marginal mandibular, cervical branches; marginal mandibular and cervical branches. CONCLUSIONS: These numerical data will have an importance during the nerve repair process of terminal branches of facial nerve in various injuries.

Protective effect of dexamethasone on fetal rat skin in experimental intrauterine ischaemia/reperfusion injury.

BACKGROUND: Perinatal asphyxia is an important cause of injury to fetal tissues such as the brain, heart, liver and gastrointestinal system. Fetal skin has also been shown to be vulnerable to intrauterine injury after intrauterine ischaemia/reperfusion (I/R) injury. AIM: To examine the effect of dexamethasone on fetal skin in intrauterine I/R injury in rats. METHODS: The response of rat fetal skin to I/R injury and maternal dexamethasone treatment were assessed by determining thiobarbituric acid reactive substances (TBARS), and myeloperoxidase (MPO) and nitric oxide (NO) metabolites. We also examined the ultrastructural changes of fetal skin. Bilateral utero-ovarian artery clamping was performed to produce ischaemia for 30 min in rats at day 19 of pregnancy, and reperfusion was achieved by removing the clamps for 60 min before fetal tissue was collected. The treatment group was given dexamethasone intraperitoneally 20 min before I/R was performed. RESULTS: TBARS, MPO and NO all increased significantly in fetal rat skin after I/R injury. Levels of TBARS, MPO and NO were significantly lower in the dexamethasone-treated group than in the I/R-only group. I/R injury produced ultrastructural damage in the epidermis. Oedema and mitochondrial damage were less severe in the dexamethasone-treated group. CONCLUSIONS: Maternal treatment with dexamethasone may have a protective effect on fetal skin in cases of I/R injury.

A combined anatomical variation of inferior epigastric vessels.

During the routine gross anatomical dissection of the right inguinal region of a 45-year-old male cadaver, a variation was observed both in the inferior epigastric artery and the inferior epigastric vein. In this case, the right inferior epigastric artery originated from the femoral artery 13 mm inferior to the inguinal ligament. Additionally, in this cadaver, the single right inferior epigastric vein drained into femoral vein 8 mm inferior to the inguinal ligament. The distal origin of the inferior epigastric artery from the femoral artery and the lower drainage of the single inferior epigastric vein to the femoral vein must be taken into consideration by surgeons.

Concomitant trastuzumab with thoracic radiotherapy: a morphological and functional study.

BACKGROUND: The purpose of this study is to elucidate if there is an additive or supra-additive toxic effects of radiotherapy (RT) and trastuzumab (T) on vascular structures when used concomitantly. METHODS: Female Wistar albino rats were treated with either 8 or 15 Gy of thoracic RT. T was applied i.p. with a dose of 6 mg/kg 2 h before RT. Four rats in each arm were killed at 6th h, 21st and 70th days after irradiation and thoracic aorta of each animal was dissected for electron microscopy. In addition, functional studies for evaluating the relaxation and contraction were carried out 21 days after RT. RESULTS: Only 15-Gy RT dose groups showed significant difference in terms of functional deterioration as more contraction than the others (P < 0.05) without any difference between RT and RT + T. However, T produced additional deficit in relaxation when added to RT, which was considered near significant (P: 0.0502). Electron microscopy showed endothelial and subendotelial damage signs in 15-Gy dose groups. T + 15-Gy arm showed more pronounced endothelial cell damage than 15-Gy RT-only arm, 70 days after RT. CONCLUSION: T and high-dose RT may lead to vascular damage that seems at least additive.

A case of individual variation of the rhomboid muscles.

During the routine gross anatomic dissection of a Turkish male cadaver; a variation of rhomboid muscles was observed on the left side. There were two rhomboid minors and three rhomboid majors coursing under the trapezius muscle. The origins of the upper and lower rhomboid minor muscles were C5, C6 and C7 vertebrae, respectively. Their insertions were to medial border of scapula, to upper part and to lower part of the spine of scapula, respectively. The origins of the upper, middle and lower rhomboid majors were C7, T1-T3 and T4-T5 vertebrae, respectively. Their insertions were to the 2/3 most inferior part of the medial border of scapula, from superior to inferior in sequence. In the examination of the literature, we could not observe such a variation of these muscles. In surgical procedures these types of variations have a clinical importance for intrathoracic muscle flap transfers and in cases with the paralysis of trapezius muscle.

Evaluation of the anatomical measurements of the temporomandibular joint by cone-beam computed tomography.

BACKGROUND: To examine the detailed anatomy of the normal temporomandibular joint (TMJ) in a large series of patients divided into different age groups. MATERIALS AND METHODS: Cone-beam computed tomography images of 100 patients included in the study. Morphometric analysis regarding mandibular con- dyle and mandibular fossa, articular tubercle and the zygomatic arch was done. The volumetric and surface measurements of mandibular condyles (total tissue volume [TV], total bone volume [BV], bone surface area [BS] and percentage of bony tissue of the mandibular condyle [BV/TV]) were also measured. RESULTS: Statistical analysis was performed and statistically significant differences according to the side of the joint, sex, and age groups were reported. Additionally, correlations between aging and all of these parameters were also determined. CONCLUSIONS: TV, BV, BS and BV/TV parameters according to side, age, and sex groups were defined for normal TMJ which may help to understand the onset and progress of TMJ disorders.

Hacettepe cartilage slicer: a novel cartilage slicer and its performance test results.

OBJECTIVE: This study investigated the performance of a cartilage slicer device referred to as the 'Hacettepe cartilage slicer'. METHODS: Forty-one cartilage pieces were harvested from eight fresh frozen human ears and measured in thickness with a digital micrometer. These pieces were randomly sliced using four different thickness settings and two different types of blades. The thicknesses of the slices and remaining pieces were measured also. Scanning electron microscopy was utilised to determine the surface smoothness of the slices. RESULTS: Thickness results showed a proportional increase with the increasing thickness setting, with a ±0.1 mm margin of error. The measurements showed that over 95 per cent of the slices' structural integrity was preserved. Although both blades provided satisfactory results, scanning electron microscopy revealed that the slices cut with a single bevel blade had superior surface smoothness. CONCLUSION: To our knowledge, the current study is the first to evaluate the performance of a cartilage slicer device. Based on the thickness results, the Hacettepe cartilage slicer fulfilled its design goals: to consistently produce slices at the intended thickness with a ±0.1 mm tolerance, and to preserve over 95.3 per cent of cartilage thickness thereby ensuring undamaged, strong cartilage slices.

Amelioration of radiation-induced lung injury by halofuginone: An experimental study in Wistar-Albino rats.

To evaluate effects of halofuginone (H) on radiation-induced lung injury (RILI), 60 rats were divided into six groups: Group (G) 1 control, G2 radiotherapy (RT) only, G3 and G4 2. 5 and 5 µg H and G5 and G6 RT + 2.5 and 5 µg H groups, respectively. A single dose of 12 Gy RT was given to both lungs. H was applied intraperitoneally with daily doses, until animals were killed at 6 and 16 weeks after RT. At 6th and 16th weeks of RT, five rats from each group were killed. Lung tissues were dissected for light and electron microscopy. Chronic inflammation, fibrosis and transforming growth factor-beta (TGF)-ß scores of all study groups were significantly different at 6th and 16th week ( p < 0.001). Chronic inflammation, fibrosis and TGF-ß scores of G2 were higher than G5 and G6 at 6th and 16th weeks of RT. At 16th week, fibrosis and TGF-ß scores of G5 were higher than G6 ( p = 0.040 and 0.028, respectively). Electron microscopical findings also supported these results. Therefore, H may ameliorate RILI. The effect of the H was more prominent at higher dose and after long-term follow-up. These findings should be clarified with further studies.

Assessment of concomitant versus sequential trastuzumab on radiation-induced cardiovascular toxicity.

There are limited data regarding effect of trastuzumab on radiation-induced cardiovascular toxicity when used sequentially or concomitantly. This experimental study aims to investigate effect of trastuzumab on radiation-induced cardiovascular toxicity with respect to the treatment sequence. One hundred and eight female Wistar albino rats were divided into six groups (G): G1 was control, G2 was trastuzumab, and G3 was radiotherapy (RT); G4 and G6 were sequential RT and trastuzumab; and G5 was concomitant RT and trastuzumab groups, respectively. Rats were killed at 6th h, 21st and 70th days after RT; thoracic aorta and heart samples were obtained. Transthoracic echocardiography and functional studies evaluating relaxation of thoracic aorta were performed. Subendothelial edema scores of thoracic aorta samples at 21st and 70th days were higher in RT groups (G3, G4, G5, and G6) ( p < 0.001). There was a deterioration of relaxation responses of thoracic aorta samples in RT groups ( p < 0.001). Cardiac fibrosis (CF) scores revealed detrimental effect of RT beginning from 6th h and trastuzumab from 21st day. RT groups showed further deterioration of CF at 70th day. Ejection fraction, left ventricular mass, and fractional shortening were significantly decreased in G4, G5, and G6. Trastuzumab may increase pathological damage in cardiovascular structures when used with RT regardless of timing.

Electron microscopic examination of effects of bogma raki and walnut on cochlea: an experimental study.

Illegal alcohol beverages known as bogma raki in our country are consumed widely in our region. The studies investigating the relationship between alcohol consumption and hearing ability report different results. In this study, we aimed to investigate the toxic effects of bogma raki that contains neurotoxic substances on cochlea by electron microscopy. To the best of our knowledge, this study is the first in the literature. A total of 48 Wistar male albino rats (aged 12-16 weeks and weighing 200-240 g) were used in the study. The rats were divided into 4 groups with 12 animals in each group. The groups include control, bogma raki, walnut, and walnut + bogma raki groups. Bogma raki (30% v/v, 9.2 ml kg(-1) day(-1)) is added to drinking water of rats in bogma raki group (n = 12) for 4 weeks. Walnut group rats (n = 12) are fed with standard rat food and walnut without limitation (10 g kg(-1) day(-1)). Bogma raki + walnut group rats (n = 12) are fed with standard rat food and walnut and bogma raki is added to drinking water. The cochleas were dissected and removed en bloc and examined by electron microscopy. Perineuronal oedema around neurons of spiral ganglion and hairy cells of organ of Corti were present in the bogma raki group, walnut group and bogma raki + walnut group under electron microscopic examination. Comparing these three groups, there were no differences in the ultrastructural pathological changes. In the ultrastructural examination of the myelinated axons forming cochlear nerve, no ultrastructural pathology was detected in all the groups.

Early protective effects of Iloprost after experimental spinal cord injury.

This investigation was undertaken to study the early protective effects of Iloprost, a stable analogue of prostacyclin, after spinal cord injury in rabbit. Sixteen adult male rabbits (New Zealand Albino) were injured by application of epidural aneurysm clip. Eight rabbits received an intravenous (i.v.) infusion of 30 micrograms kg-1 Iloprost, and eight rabbits received an infusion of saline (SF). Treatment with Iloprost started immediately after spinal cord injury and continued for one hour. Evoked potentials were recorded for each rabbit at one, 15, and 60 minutes after the spinal cord injury. Twenty-four hours later, all the rabbits were deeply anesthetized and spinal cords were removed for histopathological examinations. There was no meaningful statistical difference between cortical somatosensorial evoked potentials (CSEP) of the saline and Iloprost group. However, light and electron microscopic studies showed that the Iloprost treated group had moderate protection of myelin and axons; and limited edema. These results suggest that intravenous Iloprost treatment after spinal cord injury has a highly protective effect without any side effects.

Effects of iloprost on vasospasm after experimental spinal cord injury: an electron and light microscopic study.

It has been increasingly reported that traumatic and ischemic insults to the spinal cord may produce tissue damage through both direct and indirect mechanisms. In spite of many theories about post-traumatic spinal cord injury, there is still no satisfactory account of the exact mechanism. Vasospasm may be related to the trauma and release of vasoconstrictor or vasoactive amines. This study aims at studying the possible protective mechanisms of iloprost, a stable analogue of prostacyclin, after spinal cord injury on the rabbit. Forty-two adult male rabbits (New Zealand albino) were inflicted injuries by epidural application of an aneurysm clip to the spinal cord. Twenty-one rabbits received an i.v. infusion of 25 microg kg(-1) x h(-1) iloprost. The remaining twenty-one rabbits received an i.v. infusion of saline as the control group. Intravenous treatment started immediately after the infliction of the spinal cord injury and lasted for 1 h. Iloprost treatment had no side effects on the general physiological parameters in the rabbits. Control and iloprost treatment groups were divided into three sub-groups. The first group of animals was deeply anesthetized and spinal cords were removed 15 min after treatment. Second and third group animals were sacrificed in the 3rd and 24th hours respectively. All spinal cords were removed for light and electron microscopic examination. The width of anteriolar smooth muscle cells and the ultrastructural analysis of sulcal arterioles and venules in the ventral median fissure of spinal cords treated by iloprost revealed less thickening in all groups especially on the 24th hour group (p < 0.01), but less thickening was observed on the 3rd hour group. Iloprost-treated groups had limited edema and moderate protection of myelin and axons. These results suggest that iloprost treatment after spinal cord injury has a highly protective effect, and the possible protective effect of iloprost is resolution of vasospasm due to spinal cord injury.

The effect of povidone iodine on the corneal endothelium.

PURPOSE: Povidone iodine has been proven to be a valuable antiseptic solution in preparing the eye for surgery and is an alternative to postoperative topical antibiotics. No study has addressed the intraocular toxicity of povidone iodine after injection into the anterior chamber. We investigated the potential toxicity of povidone iodine on the corneal endothelium after injections into the anterior chamber in a rabbit model. METHODS: In this study we used 24 eyes of 12 albino rabbits. The eyes were divided into the following three groups according to the drugs tested: group A, 5% povidone iodine; group B, 10% povidone iodine; group C, balanced salt solution. The injected eyes were evaluated by biomicroscopy, specular microscopy, corneal pachymetry, and transmission and scanning electron microscopy. RESULTS: Corneal edema was observed in all eyes of groups A and B. In groups A and C, the endothelial cell morphology was not significantly changed and the mean endothelial cell count of the eyes did not change significantly (p = 0.5054). There was no significant difference in corneal thickness between groups A and C (p = 0.3823), but there was a significant difference between groups B and C ( = 0.0002). Transmission and scanning electron microscopy results were normal in group C but not in groups A and B. CONCLUSION: Povidone iodine in both 5% and 10% concentrations demonstrates severe toxicity when one drop of either concentration is placed directly in the anterior chamber. When povidone iodine is used in preparing the eye for intraocular surgery and as an alternative to postoperative antibiotics, the inadvertent leakage of povidone iodine into the anterior chamber must definitely be prevented.

Chitosan films and hydrogels of chlorhexidine gluconate for oral mucosal delivery.

Topical delivery of antimicrobial agents is the most widely accepted approach aimed at prolonging active drug concentrations in the oral cavity. As most antifungals do not posses inherent ability to bind to the oral mucosa, this is best achieved through improved formulations. Chitosan, a partially deacetylated chitin, which is a biologically safe biopolymer, prolongs the adhesion time of oral gels and drug release from them. Chitosan also inhibits the adhesion of Candida albicans to human buccal cells and has antifungal activity. The antifungal agent, chlorhexidine gluconate (Chx), also reduces C. albicans adhesion to oral mucosal cells. The aim of this study was to design a formulation containing chitosan for local delivery of Chx to the oral cavity. Gels (at 1 or 2% concentration) or film forms of chitosan were prepared containing 0.1 or 0.2% Chx and their in vitro release properties were studied. The antifungal activity of chitosan itself as well as the various formulations containing Chx was also examined. Release of Chx from gels was maintained for 3 h. A prolonged release was observed with film formulations. No lag-time was observed in release of Chx from either gels or films. The highest antifungal activity was obtained with 2% chitosan gel containing 0.1% Chx.

The early protective effects of L-arginine and Ng-nitro-L-arginine methyl ester after experimental acute spinal cord injury. A light and electron microscopic study.

The purpose of this study was to investigate the early protective effects of L-arginine and Ng-nitro-L-arginine methyl ester (L-NAME) after acute spinal cord injury. Acute spinal cord injury was performed by epidural application of an aneurysm clip at thoracic (T) 7 - 11 level. L-arginine at a dose of 750 microg/kg/min was administered 10 min before acute spinal cord injury and continued for 30 min to 10 animals (Group II). L-NAME at a dose of 250 microg/kg/min was administered 10 min before acute spinal cord injury and continued for 30 min to 10 animals (Group III). No drug was administered to 10 animals after acute spinal cord injury (Group I). Light and electron microscopic analysis were performed in all of the groups. Oedema of perineural, axoplasm or white matter in the L-arginine-treated group was less than in Group I and Group III. Thickening in the walls of the arterioles and venules in the L-arginine-treated group was much milder than in Group I and Group III. Degeneration of myelinated axons in the L-arginine-treated group was milder than in the control group. But there was no different between Group II and Group III.

Fine structure of the human coccygeal body: a light and electron microscopic study.

There is only limited data on the microscopic structure of the coccygeal body in classical textbooks. Although there are several articles describing the light microscopic structure of the organ, the data presented are rather conflicting especially when comparing glomus tumors and normal coccygeal bodies. We therefore examined the pericoccygeal soft tissues histologically with the aim of obtaining further evidence. At the light microscopic examination, coccygeal bodies were distinguished as sections of several blood vessels encapsulated by a connective tissue capsule. Small arteries within the coccygeal bodies had an unusual endothelial lining, resembling pseudostratified epithelium or neuro-epithelium. We observed increased numbers of glomus cells in a few samples. A highly tortuous course run by the small arteries was observed in the serial sections. At their electron microscopic examination, endothelial cells exhibited the features of columnar epithelial cells, though some appeared to be vacuole rich. The basal surface of the cells showed basal infoldings, but not as extensive as those of absorptive cells. External lamina, subplasmalemmal vesicles, bundles of microfilaments, groups of membrane bound organelles including mitochondria and endoplasmic reticulum were observed in glomus cells. In conclusion, it is rather difficult to use the term tumor for the coccygeal bodies when relying solely on the number of cells observed, because some segments of the coccygeal bodies were rich in glomus cells. It is more likely that the coccygeal bodies show variability in different individuals. The characteristics of the endothelium of the small arteries in coccygeal bodies needs to be examined in a wider range of specimens in order to be validated as a unique entity.