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Bilge Bilgic

Publications and source records attributed to Bilge Bilgic.

18 recordsLinked to original sources
PubMed2006

Effects of lipopolysaccharide on blood-brain barrier permeability during pentylenetetrazole-induced epileptic seizures in rats.

We investigated the effects of lipopolysachharide (LPS) on functional and structural properties of the blood-brain barrier (BBB) during pentylenetetrazole (PTZ)-induced epileptic seizures in rats. Arterial blood pressure was significantly elevated during epileptic seizures irrespective of LPS pretreatment. Plasma levels of interleukin (IL)-1, interleukin (IL)-6, nitric oxide (NO) and malondialdehyde (MDA) increased while catalase concentrations decreased in animals treated with LPS, PTZ and LPS plus PTZ. The significantly increased BBB permeability to Evans blue (EB) dye in the cerebral cortex, diencephalon and cerebellum regions of rats by PTZ-induced seizures was markedly reduced upon LPS pretreatment. Immunoreactivity for tight junction proteins, zonula occludens-1 and occludin, did not change in brain vessels of animals treated with PTZ and LPS plus PTZ. Glial fibrillary acidic protein immunoreactivity was increased in LPS, but not in PTZ and LPS plus PTZ. These results indicate that LPS pretreatment reduces the passage of EB dye bound to albumin into the brain, at least partly, by increasing plasma NO and IL-6 levels during PTZ-induced epileptic seizures. We suggest that LPS may provide protective effects on the BBB integrity during epileptic seizures through transcellular pathway, since the paracellular route remained unaffected by LPS and LPS plus PTZ.

Animals↗
PubMed2006

Retrospective study of 23 pathologically proven cases of central nervous system tuberculomas.

INTRODUCTION: Extrapulmonary manifestations of tuberculosis involving the central nervous system (CNS) due to haematogenous spread are not a rare entity. It presents as meningitis or tuberculoma. Tuberculoma is a granulomatous inflammatory process mimicking a neoplasm radiologically, so usually a biopsy is performed. MATERIAL AND RESULTS: Our study consisted of 23 pathologically proven cases of tuberculomas between 1988 and 2003. Patients were discussed clinically, radiologically and histologically. Headache, fever, weight loss and weakness are the most common clinical manifestations. Our patient's ages vary from 3 to 67 years with a mean of 31.8 years. Ninety-five percent of patients had bad social, economic and nutritional conditions. None of them were infected by human immunodeficiency virus (HIV). All patients had similar contrast-enhancing lesions radiologically. The majority of tuberculomas were located supratentorially. Only one patient presented two foci of (cerebral and cerebellar) tuberculomas. Nineteen tuberculomas were intracerebral; two were located in the cerebellum and one was intramedullary. Among those lesions, one cavernous sinus tuberculoma and one sellar tuberculoma were identified. Only two patients underwent stereotactic biopsy and 21 patients underwent surgical excision. Histopathologic examination revealed granulomatous inflammation with central caseous necrosis in all patients. DISCUSSION: Diagnosis of tuberculoma can be difficult, and in most of our cases, the clinical diagnosis was 'neoplasm'. For this reason, clinicians must always be aware of it and consider it in the differential diagnosis of central nervous system mass lesions.

Adolescent↗
PubMed2005

Time-dependent changes in failure loads of 3 biceps tenodesis techniques: in vivo study in a sheep model.

BACKGROUND: Failure load of the tendon-fixation material-bone unit has a crucial importance for the rehabilitation protocol after tenodesis procedures. PURPOSE: To investigate and compare the time-dependent changes in fixation strengths of 3 proximal biceps tenodesis techniques. STUDY DESIGN: Controlled laboratory study. METHODS: Two intraosseous techniques (suture sling and tenodesis screw) and 1 extraosseous technique (2 suture anchors) were investigated. Biceps tenodesis was performed on 45 shoulders of 26 sheep, 15 shoulders for each technique. Twelve similar cadaveric sheep shoulders (4 for each technique) provided the day 0 results. Sheep were sacrificed at 3, 6, and 9 weeks, and specimens were tested for the failure load of the tenodeses. RESULTS: All 3 tenodesis techniques were found to have similar failure loads at all time intervals tested. All 3 curves remained below the failure load of the intact tendon (862 +/- 96 N) and above their day 0 results for the study period; similarly, at each time interval, results tended to be better compared to the previous test. The tenodesis screw group exhibited significantly higher failure loads at week 3 (419 +/- 53 N) compared to day 0 values (164 +/- 45 N) (P = .009). The same level of significance was observed at week 6 in the remaining 2 groups. CONCLUSION: Tenodesis of the biceps tendon on the proximal humerus at an extra-articular site does not weaken after surgery. The tenodesis screw group had a significantly higher increase in the fixation strength within the first 3 weeks. CLINICAL RELEVANCE: No significant differences could be found between the failure loads of all 3 investigated tenodeses for the first 9 weeks.

Absorbable Implants↗
PubMed2005

Effects of atorvastatin on blood-brain barrier permeability during L-NAME hypertension followed by angiotensin-II in rats.

Recent studies suggest that 3-hydroxy-3 methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors, statins, can have direct effects on blood vessels beyond their cholesterol-lowering effects. We investigated the effects of atorvastatin on the functional and structural properties of blood-brain barrier (BBB) and the activity of astrocytes during the N(omega)-nitro-L-arginine methyl ester (L-NAME) hypertension followed by angiotensin (ANG) II. We found that decreases in concentration of serum catalase and plasma nitric oxide (NO) induced by L-NAME were significantly ameliorated by atorvastatin, whereas L-NAME-induced serum malondialdehyde and cholesterol concentration increases were significantly reduced by atorvastatin. The content of Evans blue (EB) dye significantly increased in cerebellum, left cerebral cortex and diencephalon regions but atorvastatin markedly reduced the increased BBB permeability to EB in the brain regions of animals treated with L-NAME and L-NAME plus ANG II. Brain vessels of L-NAME-treated animals showed a considerable loss of immunoreactivity of tight junction proteins, zonula occludens (ZO)-1 and occludin. Immunoreactivity for ZO-1 and occludin increased in animals treated with atorvastatin and L-NAME plus atorvastatin. Glial fibrillary acidic protein (GFAP) immunoreactivity was seen in few astrocytes in the brain sections of L-NAME, but immunoreactivity for GFAP increased in L-NAME plus atorvastatin-treated animals. We suggest that long-term L-NAME treatment may affect BBB permeability through disruption of tight junction proteins, at least partly, via decreased NO concentration and increased oxidant capacity; the improvement of BBB integrity and astrocytic activity would be more closely associated with the action of atorvastatin favoring the increase in anti-oxidant capacity and expression of tight junction proteins and GFAP.

Angiotensin II↗
PubMed2005

Diffuse thoracic lymphangiomatosis with disseminated intravascular coagulation in a child.

An 8.5-year-old girl who presented with chronic cough and hemoptysis underwent a CT scan of the chest showing diffuse mediastinal and parenchymal infiltration and pleural effusion, and laboratory findings showed disseminated intravascular coagulation. Disseminated lymphangiomatosis was diagnosed after an open-lung biopsy. She was treated by systemic steroids, interferon, tamoxifen, chemotherapy, and radiation but died of respiratory failure and disseminated intravascular coagulation 2 years after the diagnosis. This patient represents a rare presentation of diffuse pulmonary lymphangiomatosis together with disseminated intravascular coagulation, involving both the mediastinum and pulmonary parenchyma, in a child.

Adrenal Cortex Hormones↗
PubMed2004

Effects of lipopolysaccharide on the radiation-induced changes in the blood-brain barrier and the astrocytes.

The use of radiation to improve the efficacy of chemotherapy on malignant brain tumors is also known to cause side effects on vascular endothelial cells and astrocytes in normal parts of the brain. We investigated the effects of lipopolysaccharide (LPS) on the functional and structural properties of blood-brain barrier (BBB) and the activity of astrocytes during whole-brain irradiation in rats. The permeability of the BBB to Evans blue (EB) dye significantly increased in the cerebral cortex, diencephalon and cerebellum regions of rats exposed to irradiation (P<0.01). In contrast, the BBB permeability in irradiated rats was significantly reduced by LPS (P<0.05). Tumor necrosis factor-alpha (TNF-alpha) levels were increased following LPS, irradiation and irradiation plus LPS (P<0.05, P<0.01). Irradiated brain vessels showed a considerable loss of staining intensity of tight junction proteins Zonula occludens-1 (ZO-1) and occludin. Staining for Zonula occludens-1 and occludin was intensive in animals treated with LPS and irradiation plus LPS. Glial fibrillary acidic protein (GFAP) immunoreactivity was seen in very few astrocytes of irradiated brains. However, this staining showed an increased positive intensity in the brain sections of LPS-treated as well as of irradiation plus LPS-treated animals. These results indicate that LPS reduces the passage of exogenous vascular tracer EB-binding albumin into the brain, at least partly, by increasing the expression of tight junction proteins and GFAP, following the irradiation. We suggest that irradiation may affect paracellular permeability through disruption of tight junction proteins, Zonula occludens-1 and occludin, and LPS could provide beneficial effects on the BBB integrity and the astrocytes against irradiation damage.

Animals↗
PubMed2004

The negative effect of hyperbaric oxygen therapy at the acute phase of electrochemical esophageal burn induced by button battery ingestion.

OBJECTIVE: Ingestion of button battery, if lodges in esophagus, causes mucosal destruction in esophagus and may damage surrounding tissues due to electrochemical reactions which may lead to esophagus perforation, tracheosefageal fistula and other serious problems. We designed an experimental study to test the effect of hyperbaric oxygen therapy on battery induced electrochemical tissue damage in the esophagus of a rabbit model and possible change with duration of contact time. METHODS: Button batteries were inserted in esophagus of 40 rabbits which were divided into four groups. Groups 1 and 2 had 15 min of duration of contact time of battery in esophagus, while Groups 3 and 4 had 30 min. Groups 1 and 3 had hyperbaric oxygen therapy for 3 days; Groups 2 and 4 did not. At the end of 3rd day all animals were sacrified and samples were taken from the esophagus for determination of malondialdehyde levels and for histopathological examination to compare: mucosal destruction, muscular layer involvement, perforation and tracheal involvement between groups. RESULTS: Malondialdehyde levels, mucosal destruction, muscular layer involvement, perforation and tracheal involvement were significantly higher in groups which had 30 min of contact time compared to groups which had 15 min. The same assessments were significantly higher in Group 1 (15 min of contact time with hyperbaric oxygen therapy) compared to Group 2 (15 min of contact time without hyperbaric oxygen therapy). However, the difference between Group 3 (30 min of contact time with hyperbaric oxygen therapy) and Group 4 (30 min of contact time, no hyperbaric oxygen therapy) was not significant. CONCLUSION: Our study demonstrated that if contact time is 15 min HBO had an additive adverse effect to electrochemically burned esophagus by increasing free radicals and eventually tissue damage. However, if the contact time is 30 min its adverse effect is shielded by huge electrochemical destruction due to long contact time.

Acute Disease↗
PubMed2004

Reactions of connective tissue to mineral trioxide aggregate and amalgam.

The purpose of this study was to evaluate the subcutaneous connective tissue reactions to ProRoot, mineral trioxide aggregate (MTA; Dentsply), and Oralloy, high-copper amalgam (Coltene). These materials were placed in polyethylene tubes and implanted into dorsal connective tissue of Wistar albino rats, and tissue biopsies were collected and histologically examined 7, 15, 30, 60, and 90 days after the implantation procedure. The presence of inflammation, predominant cell type, calcification, and thickness of fibrous connective tissue were recorded. Scores were defined as follows: 0, none or few inflammatory cells, no reaction; 1, < 25 cells, mild reaction; 2, 25 to 125 cells, moderate reaction; 3, > or = 125 cells, severe reaction. Fibrous capsule was categorized as "thin" when thickness was < 150 microm and "thick" at > 150 microm. Necrosis and formation of calcification were recorded. Both materials were well tolerated by the tissues in a 90-day evaluation period. One notable finding is the presence of dystrophic calcification in connective tissue adjacent to MTA; this finding is consistent with the hypothesis of hard tissue induction by this material.

Aluminum Compounds↗
PubMed2003

Synovial sarcoma: a rare tumor of larynx.

Synovial sarcoma is a soft tissue sarcoma of unknown histogenesis and occurs predominantly in the lower extremities of young adults. The head and neck is a relative rare location. There are about 10 cases with laryngeal localization in the literature. We present a 24 year-old male with an endolaryngeal mass. Incisional biopsy and the hemilaryngectomy material revealed a biphasic synovial sarcoma. One year later a local recurrence occurred. Tumor excision and neck dissection were performed. Radiotherapy was added. Six months later lung metastases was discovered on thoracic CT. The patient received chemotherapy for 6 courses. The metastases responded well to chemotherapy and the patient is now alive without tumor on radiological and clinical examination after 3.5 years of follow-up.

Adult↗
PubMed2003

Malignant peripheral nerve sheath tumors associated with neurofibromatosis type 1.

We report 4 cases of malignant peripheral nerve sheath tumors (MPNST) with neurofibromatosis type 1 (NF1). Mean age was 29.5. Two of them had a family history. Three of them were male. All of them had enlarging mass and pain in the background of neurofibromas. Locations were popliteal, thigh and forearm. The masses were greater than 5 cm in diameter in each case. In two cases the mass was showing continuity with a nerve. One patient had a nonossifying fibroma as well as a MPNST. Wide excision and radiotherapy were applied to three of the patients. One of them did not take any therapy after surgical resection. Two of the patients died of lung metastases after a mean period of 12.5 months. In a majority of NF1 patients MPNST emerges from a preexisting neurofibroma. The patients with NF1 are at greatest risk for developing sarcomas, so they should be followed closely.

Adult↗
PubMed2003

Glioblastoma with lymph node metastases.

Metastatic spread of malignant astrocytomas is rare and documented in very few patients with this tumor. Both pathologists and clinicians may confront more of these cases as the patients live longer. We present a 40-year-old-man with glioblastoma multiforme metastasizing to the supraclavicular lymph node after surgery. The tumor was located at the parietal convexity and several lymphadenopathies occured after surgery.

Adult↗
PubMed2003

Skull Base Plasmacytoma in a Patient with Light Chain Myeloma.

Skull base involvement of plasmacytoma is reported in a patient with light chain myeloma. A 39-year-old man was admitted after experiencing paresthesia on the left side of the face and left arm, intermittent diplopia, and hoarseness for 2 years. Cranial magnetic resonance imaging revealed a large midline mass extending from the middle and posterior skull base into the upper two cervical vertebrae. An extramedullary plasmacytoma associated with light chain multiple myeloma was diagnosed after biopsy of the mass and laboratory investigations. The imaging findings and clinical features associated with this rare site of extramedullary plasmacytoma involvement are reported.

Case Reports↗
PubMedDate not supplied

The effect of short- versus long-term administration of alpha tocopherol on the survival of random flaps in experimental diabetes mellitus.

The effects of short- versus long-term alpha tocopherol administration on oxidative stress and survival of dorsal random flaps were studied in diabetic rats. Seven groups, with 20 rats in each, were constructed: (1) control, (2) noncontrolled diabetes, (3) noncontrolled diabetes+short-term alpha tocopherol, (4) noncontrolled diabetes+long-term alpha tocopherol, (5) insulin treatment, (6) insulin+short-term alpha tocopherol, and (7) insulin+long-term alpha tocopherol. After 3 months of diabetes, dorsal McFarlane flaps were raised. Flap viability and free-radical measurements with histopathological examination were investigated. Mean flap survival in Groups I to VII were 84.0+/-2.2%, 55.0+/-2.4%, 57.0+/-2.5%, 57.8+/-3.7%, 64.1+/-4.1%, 70.0+/-4.9%, and 77.0+/-6.6%, respectively. Free-radical concentration, as assessed with luminol- and lucigenin-enhanced chemiluminiscence, was inversely correlated with flap survival. The results for viability and free-radical concentrations were significant between Groups 1, 2, 5, 6, and 7. Random flaps in diabetic animals showed significantly greater necrosis compared with controls. Among the diabetic animals, group receiving combination of insulin and long-term alpha tocopherol treatment had the greatest flap viability and least tissue free-radical concentration. Histopathological studies showed a hyalinization of arterioles in diabetics with long-term alpha tocopherol treatment protecting the vessel wall. In conclusion, random flaps in experimental diabetes mellitus show greater tissue oxidative stress and necrosis, which is only partially corrected with insulin treatment. Long-term antioxidant supplementation as an adjunct to insulin further lowers the oxidative stress, protects vessel structure and function, and therefore increases flap survival.

Animals↗
PubMedDate not supplied

An intrasellar germinoma with normal cerebrospinal fluid beta-HCG concentrations misdiagnosed as hypophysitis.

A patient with an intrasellar germinoma leading to pituitary stalk thickening is reported. The patient, a 24-year old woman, presented with hyperprolactinemia, secondary hypothyroidism, and hypogonadotropic hypogonadism with no evidence of diabetes insipidus. Cerebrospinal fluid (CSF) examination revealed an increased number of lymphocytes and histiocytes. Although beta-HCG concentration was normal (<2 mIU/mL) in the CSF, increased beta-HCG concentration was detected in the serum. Systemic glucocorticoid treatment led to a decrease in CSF cell count, but no regression of the sellar mass was noted. A diagnostic biopsy was performed and showed an intrasellar germinoma. The patient underwent conventional radiotherapy. Complete resolution of the mass lesion and normalization of beta-HCG concentration in the serum were observed three months after radiotherapy. The presence of intrasellar mass lesion in association with pituitary stalk thickening may cause difficulties in the differential diagnosis. Histopathological examination is essential in equivocal cases in order to reach accurate diagnosis and apply the most appropriate therapy.

Adult↗
PubMedDate not supplied

A previously unreported etiology of trigger toe.

Trigger toe is a rare entity, with only a few cases reported in the literature. It is usually seen in ballet dancers as a result of compression of the flexor hallucis longus tendon in the tarsal tunnel beneath the medial malleolus. We report a case of trigger toe due to a constricting lesion on the extensor hallucis longus tendon.

Constriction, Pathologic↗
PubMedDate not supplied

Histomorphometric evaluation and clinical assessment of endosseous implants in iliac bone grafts with shortened healing periods.

PURPOSE: In the present study solid monocortical hipbone onlay grafts of the maxilla were analyzed histologically after a healing period of 3 months. The clinical success of the implants placed in the grafted bone was evaluated. MATERIALS AND METHODS: Nineteen patients underwent augmentation with avascular iliac bone. A 2-stage procedure was performed with a 3-month healing period between graft and implant placement. At implant placement bone biopsy samples were taken at the proposed implant sites. RESULTS: Of the 117 implants placed, 1 was not osseointegrated at the time of abutment connection. No implants were lost after loading during an observation period of up to 3 years. Clinical appearance of the augmented bone after 3 months showed a dense cortical layer with good blood perfusion. Histologic specimens were analyzed quantitatively and showed an average of 43.2% newly formed bone. DISCUSSION: Histomorphometry showed that the amount of newly formed bone after 3 months was comparable to that found after a healing period of 4.5 months. The clinical success of the implants placed after the shortened healing period was comparable to that found in nonaugmented bone. CONCLUSION: This study showed that after avascular iliac bone grafting, 3 months of revascularization was sufficient to ensure the secure placement of dental implants in second-stage surgery for this patient population.

Adolescent↗