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Öğe Biocompatibility of vitallium as ossicular reconstruction material in the middle ear: experimental animal study(TAYLOR & FRANCIS AS, 2005) Ulku, CH; Avunduk, MC; Uyar, Y; Arbag, HConclusion. Although long-term data will be necessary for confirmation, the result of this preliminary study indicates that vitallium may be a good alternative material for ossicular replacement prostheses in the middle ear. Objectives. To investigate the biocompatibility of vitallium (Co-Cr-Mo) as ossicular reconstruction material in the rabbit middle ear, and to compare the results with those obtained with titanium, well known as a highly biocompatible material, and non-implanted control groups. Material and methods. Eighteen female New Zealand White rabbits were anesthetized. The tympanomeatal flap was elevated and 12 vitallium and 12 titanium implants were placed in the bulla away from the ossicles in 24 middle ears. Six rabbits were used as non-implanted controls. All animals were sacrificed under general anesthesia on the 180th day after implantation. The temporal bones were removed, fixed in 10% buffered paraformaldehyde and decalcified for a week in EDTA. Tissue samples were then prepared using an Autotechnicon and embedded in paraffin. Sections (30-mum thick) were cut with a microtome, stained with hematoxylin-eosin, von Gieson's stain and fibroblast growth factor (FGF) and examined under a light microscope. The numbers of lymphocytes, collagen fibers and FGF-positive cells were determined in all three groups. Results. There was no significant difference in the numbers of collagen fibers between the groups (P > 0.05). No significant differences were found in the numbers of lymphocytes and FGF-positive cells between the titanium and vitallium groups (p > 0.05). The differences in the numbers of lymphocytes and FGF-positive cells between the control and other groups were found to be significant (p < 0.05).Öğe Cadmium and iron accumulation in rat lens after cigarette smoke exposure and the effect of vitamin E (alpha-tocopherol) treatment(TAYLOR & FRANCIS INC, 1999) Avunduk, AM; Yardimci, S; Avunduk, MC; Kurnaz, LPurpose. Cadmium accumulation in the lens has been implicated in cataractogenesis of chronic smokers. This study was planned to evaluate whether or not in vivo cigarette smoke exposure causes cadmium accumulation in rat lens, and possible protective effect and mechanism of alpha-tocopherol (vitamin E) treatment on cataractogenesis. Methods. 28 male Wistar rats were randomly divided into four equal groups. Group 3 and 4 rats were exposed to cigarette smoke over ninety consecutive days, and Group 1 and 2 rats were treated in a similar fashion but exposed only to room air. Additionally, vitamin E was given to Group 2 and 4 rats. Results. Significantly higher iron levels were observed in the lenses of Group 3 rats compared to other groups. With respect to cadmium, Group 3 and 4 rats had significantly higher levels compared to Group 1 and 2 rats. Although vitamin E treatment prevented iron accumulation in Group 4 rats, it had no effect on cadmium concentrations. Distinct histopathological changes observed in Group 3 rats were not present in Group 4 rats. Conclusion. Our study demonstrates that in vivo cigarette smoke exposure causes accumulation of cadmium in rat lens and IM vitamin E treatment does not affect this accumulation. The protective effect of vitamin E treatment on smoke exposed rat lens seems to be mediated by blockage of iron accumulation in the lens.Öğe Cataractous changes in rat lens following cigarette smoke exposure is prevented by parenteral deferoxamine therapy(AMER MEDICAL ASSOC, 1999) Avunduk, AM; Yardimci, S; Avunduk, MC; Kurnaz, LObjectives: To test whether iron accumulation in the lens following cigarette smoke exposure is the principal mechanism in smoke-related cataractogenesis and to assess the possible protective effect of deferoxamine mesylate treatment against lenticular degeneration with in vivo exposure to cigarette smoke. Methods: Thirty-two male Wistar rats were randomly divided into 4 equal groups. Groups 3 and 4 rats were exposed to cigarette smoke for I hour each day for 90 consecutive days, and groups 1 and 2 rats were treated in a similar manner but exposed only to room air. In addition, deferoxamine was given subcutaneously to groups 2 and 4 rats. Both eyes of all the animals were then enucleated and 1 eye prepared for histopathological examination. The fellow eye was used to measure iron, calcium, zinc, and cop-per levels. Results: Significantly higher iron and calcium and lower zinc levels were observed in the lenses of group 3 rats compared with those in the other groups. Similar comparisons performed between groups 1 and 2, 1 and 4, and 2 and 4 did not show any significant difference. Copper concentrations did not differ between groups. Distinct histopathological changes in the anterior lens epithelium, such as hyperplasia, hypertrophy, and epithelial multilayering, and the presence of swollen epithelial cells overlying the posterior lens capsule, observed in group 3 rats, were not present in the other groups. Conclusions: Cataractogenesis following cigarette smoke exposure in rats was associated with the accumulation of iron, and concurrent deferoxamine therapy prevented such cataract formation. Clinical Relevance: Our results may apply to human cataract formation associated with cigarette smoking, so such pathogenesis may be prevented by concurrent parenteral deferoxamine treatment Clinical studies are needed, however, to determine the value of this suggestion.Öğe Determination of operation time in colorectal diseases: Preoperative chemotherapy application(ACADEMIC PRESS INC ELSEVIER SCIENCE, 2005) Sahin, M; Erikoglu, M; Ozer, S; Tekin, A; Boz, S; Golcuk, M; Avunduk, MCBackground. Our aim was to determine the time it takes for wound healing to return to normal in cases where patients have undergone preoperative chemotherapy. Materials and methods. Eighty-four Wistar-albino rats were included in the study. Twelve of them were placed in the control group (Group 1), with no further drug administration. Another 12 rats were placed in a sham group (Group 11) and were peritoneally injected with 1 cc of isotonic saline solution 5 days a month, for a period of 6 months. The remaining 60 rats were placed in five chemotherapy groups (Groups III-VII) and were administered 20 mg/kg 5-fluorouracil through peritoneal injection, 5 days a month for a period of 6 months. At the end of the sixth cure, 12 rats from the control (Group 1), sham (Group II), and chemotherapy groups (Group III) were operated on, and an intestinal transsection. was applied to the rectosigmoid junction, followed by one-by-one anastomosis using 5/0 vicryl. Other groups (Groups IV-VI) with chemotherapy treatment were operated on at 1-week intervals and subjected to the same procedure. The subjects were reoperated on on the eleventh day. A full-layer 4 x 4 cm piece was removed from the abdominal wall containing the previous incision line at the middle, for tensile strength pressure measurements. In addition, a 4 cm colon segment was removed for bursting pressure measurements. Plasma albumin and tissue hydroxyproline levels were measured, and fibroblast numbers were counted in the sections prepared from the abdominal wall. Results. The control and sham groups were found to be similar to each other with respect to all parameters measured (P > 0.05). Significant reductions were observed in all parameters in the early chemotherapy groups compared with the control and sham groups (P <0.05). All parameters measured in Groups V, VI, and VII were found to be similar to those in the control and sham groups (P <0.05). Conclusion. Wound healing is impaired in rats with chemotherapy, but following the second week after the chemotherapy, disrupted parameters return to their normal levels. (C) 2005 Elsevier Inc. All rights reserved.Öğe The effects of dimethyl sulfoxide on liver damage caused by ischemia-reperfusion(ELSEVIER SCIENCE INC, 2004) Sahin, M; Avsar, FM; Ozel, H; Topaloglu, S; Yilmaz, B; Pasaoglu, H; Avunduk, MCIntroduction. The aim of this study was to investigate the effects of dimethyl sulfoxide on liver damage caused by ischemia-reperfusion after portal vein clamping. Material and methods. Forty New Zealand rabbits were divided into three groups with the portal veins of all the rabbits except the sham group clamped for 30 minutes: group I, sham procedure; group II, control group; and group III, 500 mg/kg DMSO. The drug was administered IM in the left inguinal region 30 minutes before the operation. Blood samples (5 mL) were taken from the animals at 15, 30, and 45 minutes. At the end of the experiment 1 g of liver tissue samples were obtained. Malondialdhyde (MDA), nitric oxide (NO), AST, ALT, and LDH plasma levels were measured in the blood samples. Liver tissue samples stained with hematoxylin eosin were examined under light microscopy for histopathological changes. Finding. The liver enzymes in both clamping groups increased significantly compared with the sham group (P < .01). Enzyme levels of the DMSO group decreased significantly compared to the control clamping group (P < .05). Similar to the enzyme changes, MDA and NO levels increased in the portal vein clamping versus the sham group and decreased in the drug-administered group versus the control clamped group (P < .03). The severity of histopathological changes was less in the DMSO group than in the clamped controls. Conclusion. DMSO decreased the severity of liver damage after portal vein clamping.Öğe Effects of gender on the severity of sepsis(SPRINGER, 2005) Erikoglu, M; Sahin, M; Ozer, S; Avunduk, MCPurpose. To investigate the differences between male and female rats and the effects of sex hormones on tissue changes in the lung and liver in a sepsis model. Methods. Sixty Sprague-Dawley rats were divided into six groups of ten. Groups 1 and 2 were the control male and female groups, respectively, subjected only to sepsis; groups 3 and 4 were the male and female groups, respectively, subjected to sepsis, then given 0.04 mg/kg estrogen + progesterone (E-P) intramuscularly (i.m.); and groups 5 and 6 were the male and female groups, respectively, subjected to sepsis, then given 0.5 mg/kg testosterone ( T) i.m. The rats were killed and the histopathological changes in the lung and liver were examined, and plasma endotoxin levels were measured. Results. Histopathological examination revealed less congestion, portal inflammation, and focal necrosis of the liver, and less congestion, edema, and emphysematous and inflammatory changes in the lung in the E-P groups than in the other groups. Moreover, signs of systemic endotoxemia in plasma were proportionally less in the female rats and in the E-P groups than in the male rats and the T groups. Conclusion. Female rats subjected to sepsis showed less liver and lung tissue damage and less systemic endotoxemia than male rats, because of the effects of female sex hormones.Öğe Electron-microscopic alterations of the peritoneum after both cold and heated carbon dioxide pneumoperitoneum(ACADEMIC PRESS INC ELSEVIER SCIENCE, 2005) Erikoglu, M; Yol, S; Avunduk, MC; Erdemli, E; Can, ABackground. Carbon-dioxide (CO2) is used universally as an insufflation agent to create a laparoscopic pneumoperitoneum. In this study, we aimed to examine the electron and light microscopic alterations of the peritoneum after both cold-dry and heated-humidified CO, pneumoperitoneum. Materials and methods. Thirty male Sprague-Dawley rats were used in this study. The rats were separated into three groups each comprising 10 rats. Group-I: (Control group): Gas insufflation was not applied to these animals. Group-II: These animals received standard cold-dry (21 degrees C, 2% relative humidity) CO2. Group-III: These animals received heated-humidified (40 degrees C, 98% relative humidity) CO2. In groups II and III, peritoneal gas was emptied 2 h after pneumoperitoneum. application. All rats were killed after 12 h. Peritoneal samples were examined both by scanning electron and light microscopy by two different pathologists who were not aware of the groups. Results. According to light microscopic examination; in group II and III, cellular response (increased lymphocyte) was significantly higher than the control group (P < 0.01). Similarly, in group II cellular response was significantly higher than group Ill. (P < 0.01). There was no difference in increased capillarity among all groups. (P > 0.05). According to scanning electron microscopic examination, in group I, normal peritoneum was covered by a sheet of flat mesothelial cells densely covered with microvilli. No intercellulary clefts and no free basal lamina were detected. In group II, drastic alterations of the surface layer were seen. The mesothelial cells had extreme desquamation, and the basal membrane was clearly visible. In group III, the mesothelial cells had bulged up to the surface layer and retracted. Intercellulary clefts become visible, but the basal lamina was not seen. Conclusions. Electron and light microscopic examination revealed that heated-humidified CO results in less peritoneal alteration than cold-dry CO2. Accordingly, we believe that heated-humidified CO2 is more suitable for pneumoperitoneum. application in laparoscopic surgery especially in selected cases. (c) 2005 EIsevier Inc. All rights reserved.Öğe Etanercept treatment in the endotoxin-induced uveitis of rats(ACADEMIC PRESS LTD- ELSEVIER SCIENCE LTD, 2004) Avunduk, MC; Avunduk, AM; Oztekin, E; Baltaci, AK; Ozyazgan, Y; Mogolkoc, RThis study was conducted to investigate therapeutic value of a soluble tumor necrosis factor-alpha (TNF-alpha) receptor, etanercept, in a rat model of endotoxin-induced uveitis (EIU). Forty-two inbred male Lewis rats were divided into seven equal groups. 200 mug of Escherichia coli 055:1355 lipopolysaccharide, (LPS) was injected in one hind footpad of the Groups 2, 3, 4, 5, 6, and 7 rats. Group 5, 6, and 7 rats also received subcutaneous etanercept 24 hr prior to LPS injection at a dose of 0(.)4 mg kg(-1). Group 1 rats were used as controls. Eight, 24, and 48 hr after treatment clinical uvetis scores (miosis, iris hyperemia, and hypopyon) were assessed by a masked observer and the rats were euthanized. Neutrophil leukocytes, CD8 +, CD4 +, and CD45RO + cells in the anterior uveal tissue were counted either after hematoxylin-eosin or monoclonal antibody staining. TNF-alpha. levels were also measured in the aqueous humor samples by an ELISA method. Etanercept treatment significantly improved clinical uveitis scores at all examination points compared to the LPS injected animals. The improvement was almost complete expect for the miosis score, since no significant difference was detected between the controls and LPS + Etanercept treated animals at all examination points. Cell counts were also at significantly lower levels in LPS + Etanercept treated animals at all examination points, except for CD8 + and CD45RO + cell counts at 24 hr examination point. There was no significant difference between the controls and LPS + Etanercept treated animals at all examination points as with CD4 + and CD45RO + cell counts at 48 hr. Our data showed that etanercept had a definite effect on the treatment of EIU. Further studies should clarify its efficacy on clinical uveitis conditions. (C) 2004 Elsevier Ltd. All rights reserved.Öğe Glomangioma of the middle ear(TAYLOR & FRANCIS LTD, 2004) Uyar, Y; Ulku, CH; Koral, H; Avunduk, MC; Atici, SSA 62-year-old female was admitted to our clinic in October 1999 with a 6-year history of hearing loss, tinnitus and otorrhea in the right ear. Physical examination showed a polypoid mass arising from the right middle ear and extending into the external auditory canal. Serohemorrhagic otorrhea was also observed. Serious hemorrhage occurred while taking a biopsy. The histopathologic diagnosis was a glomangioma. MRI demonstrated a hypervascular mass (10x15 mm(2)) completely filling the right middle ear. Preoperative embolization of the ascending pharyngeal artery was carried out. The tumor was completely resected via a transmastoid approach. No complications were observed postoperatively. At the most recent follow-up examination, 72 months after the operation, no sign of disease was present. The modified radical mastoidectomy approach used in this case proved to be a safe and efficacious method for removing the glomangioma.Öğe Hyperphosphatemic tumoral calcinosis(LIPPINCOTT WILLIAMS & WILKINS, 2000) Savaci, N; Avunduk, MC; Tosun, Z; Hosnuter, M[Abstract not Available]Öğe Iatrogenic epidermal inclusion cyst of the parapharyngeal space: Unusual complication of ear surgery(THIEME MEDICAL PUBL INC, 2004) Ulku, CH; Uyar, Y; Kocaogullar, Y; Avunduk, MCA 46-year-old man presented with a 12-month history of a slow-growing mass at the right anterior temporal and superior parotid region. He had a history of chronic otitis media and had undergone a modified radical mastoidectomy for cholesteatoma 5 years earlier. Physical examination revealed a sinus tract and diffuse soft tissue mass measuring 4 cm in diameter spread throughout the region of the right anterior temporal and superior parotid areas. Magnetic resonance imaging (MRI) showed three separate masses, including contrast material in the right superior parotid region and lateral skull base. The patient underwent a preauricular infratemporal approach. Six months later, a sinus tract recurred at the inferior border of the right zygomatic arch. MRI showed multiple masses in the right prestyloid parapharyngeal space, which were resected through a transparotid approach. The histopathologic diagnosis was an epidermal inclusion cyst (EIC). One year after the operation the patient was in good health and there was no sign of disease. EICs are rare tumors that are seen when epidermal elements are included in the dermis, which can follow trauma. EICs are unusual in the parapharyngeal space. Thus, until they become clinically observable, primary benign growths may not be recognized in this region. EICs must be considered in the differential diagnosis of growths in the parapharyngeal space, particularly among patients with a prior history of tympanomastoid surgery on the tumor side.Öğe Increased expression of epidermal growth factor receptors in the tracheal epithelia after topical mitomycin-C in rabbits(ELSEVIER SCI LTD, 2005) Arbag, H; Avunduk, MC; Ozer, B; Ozturk, K; Ulku, CHThe aim is to examine histopathological changes and expression of epidermal growth factor receptor (EGFR) in tracheal epithelia caused by application of topical mitomycin-C (MMC) in rabbit model after the tracheotomy procedure. The conventional tracheotomy was performed in 16 rabbits. They were randomly divided into two equal groups. The first group was applied MMC at a concentration of 0.4 mg/ml around tracheotomy for 5 min, and the other group was not taken a treatment as a control. The animals were sacrificed at the end of 4 weeks. Their tracheas were evaluated with H&E and Masson's trichrome histochemically, and with antiepidermal growth factor receptor immunohistochemically. Results showed that there was no significant difference between MMC and control group for inflammatory cells (P = 0.09). The numbers of fibroblasts and subepithelial tissue thickness in the group exposed to MMC were significantly lower than the control group (P < 0.05). In contrast, the percentage of EGFR in the application of MMC group was significantly higher than the control croup (P < 0.05). The application of topical MMC on airway epithelia after tracheotomy showed significant elevation in the levels of epithelial EGFR expression compared to controls in a rabbit model. The activation of epithelial EGFR may facilitate epithelial healing, but further studies are needed to assess the effect of topical MMC on respiratory epithelia. (c) 2004 Elsevier Ireland Ltd. All rights reserved.Öğe Inferior laryngeal paraganglioma presenting as plunging goiter(OXFORD UNIV PRESS INC, 2004) Aribas, OK; Kanat, F; Avunduk, MCParagangliomas are uncommon slow-growing neuroendocrine tumors that may arise from the extra-adrenal paraganglia. Paragangliomas of the inferior and superior laryngeal paraganglia are known as laryngeal paraganglioma. Inferior laryngeal paraganglioma, which is also called subglottic paraganglioma, is very seldomly observed. To our knowledge only 24 patients with subglottic paraganglioma have been found. We present a 77-year-old mate patient who has been previously followed-up for cervical goiter, which has a progressive enlargement into the mediastinum, causing severe tracheal obstruction. The tumor was completely and easily resected via median sternotomy with collar incision and finally diagnosed as inferior laryngeal paraganglioma. The present case is the first subglottic laryngeal paraganglioma descending into the visceral compartment of the mediastinum in the literature. (C) 2003 Elsevier B.V. All rights reserved.Öğe Periodontal treatment of two siblings with juvenile hyaline fibromatosis(BLACKWELL PUBLISHING, 2005) Hakki, SS; Ataoglu, T; Avunduk, MC; Erdemli, E; Gunhan, O; Rahman, NBackground and Aim: Juvenile hyaline fibromatosis (JHF) is an autosomal recessive disease that presents with multiple subcutaneous nodular tumours, gingival fibromatosis, flexion contractures of the joint and hyaline material accumulation in extracellular area. Recently, the causative gene for JHF, capillary morphogenesis protein 2 (CMG2) was identified. In this case report, periodontal status, treatment and follow-up together with histopathologic evaluation of gingival tissue specimens and mutation screening of two JHF cases are presented. Case Reports: A 10-year-old female (case 1) and her 3-year-old brother (case 2) were first examined in our department with a complaint of gingival hyperplasia in 1991. Symptoms of the disease were detected in two of four siblings in the family. Several gingivectomy operations were carried out over 11 years with hygiene motivation and initial phase therapy. After the last gingivectomy operation in 2002, the patients were reviewed frequently. Results and Conclusions: Although there was linear marginal gingival inflammation, no remarkable enlargement was noted at last appointment. Histopathological findings showed increased amounts of subepithelial nodular connective tissue, thinned epithelial mucosa, separated inter-cellular bridges and decreased numbers of connective tissue cells in gingival tissue samples. Electron microscopic examinations supported the histopathological findings. Mutation screening of CMG2 demonstrated that the siblings were homozygous for a pathogenic missense mutation, V386F. Our clinical findings demonstrate that gingivectomy is useful and frequent periodontal visits are important for maintaining oral hygiene and decreasing growth rate of gingiva in JHF.Öğe Prevention of lens damage associated with cigarette smoke exposure in rats by alpha-tocopherol (Vitamin E) treatment(ASSOC RESEARCH VISION OPHTHALMOLOGY INC, 1999) Avunduk, AM; Yardimci, S; Avunduk, MC; Kurnaz, L; Aydin, A; Kockar, MC; Delibasi, TPURPOSE. TO evaluate the possible protective effect and mechanism of cu-tocopherol (vitamin E) treatment on lens degeneration associated with in vivo exposure to cigarette smoke and to further clarify the role of iron in cigarette smoke-generated lens damage. METHODS. Twenty-eight male Wistar rats were randomly divided into four equal groups. Rats in groups 3 and 4 were exposed to cigarette smoke for 1 hour each day over 90 consecutive days, and rats in groups 1 and 2 were treated in similar fashion but only exposed to room air. Additionally, vitamin E was given to the rats in groups 2 and 4 via intramuscular route. At the end of the study, both eyes of ail the animals were enucleated; one eye was prepared for histopathologic examination, and the fellow eye was used for the measurement of iron and calcium levels. RESULTS, Significantly higher iron and calcium levels were observed in the lenses of group 3 rats than in other groups. Similar comparisons performed between groups 1 and 2, groups 1 and 4, and groups 2 and 4 did not show any significant difference. Distinct histopathologic changes in the anterior lens epithelium, such as hyperplasia, hypertrophy, epithelial multilayering, and the presence of epithelial cells over posterior lens capsule, observed in group 3 rats were not present in other groups. CONCLUSIONS. Cataractogenesis after cigarette smoke exposure was associated with an accumulation of iron and calcium in the rat lens, and vitamin E supplementation protected such accumulations and cataractogenesis.Öğe Pure squamous cell carcinoma after intravesical BCG treatment - A case report(KARGER, 2005) Yurdakul, T; Avunduk, MC; Piskin, MMBesides the commonly seen side effects of intravesical BCG instillations, very rare complications have been reported including new tumor formation other than transitional cell carcinoma of the bladder. Here we report the first case of pure squamous cell carcinoma formation in a BCG-treated patient with pure transitional cell carcinoma. Copyright (C) 2005 S. Karger AG, Basel.
