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H Aydin

Publications and source records attributed to H Aydin.

At least 19 recordsLinked to original sources
PubMed2001

Patterns of failure following CT-based 3-D irradiation for malignant glioma.

BACKGROUND: This retrospective study was undertaken to analyze the patterns of failure in patients with malignant glioma after localized irradiation. PATIENTS AND MATERIALS: Recurrence patterns of 46 patients with malignant glioma (glioblastoma: 24, anaplastic astrocytoma: 15, anaplastic oligodendroglioma: 5, unclassified malignant glioma: 2) were studied using CT/MR scans and radiotherapy plan-plots. All patients were operated before and a total dose of 5,940 cGy was given after CT assisted and individually configurated 3-D planning using 7-15 slices at an in between distance of 5 mm. The target volume included a 2-3 cm margin beyond the tumor indicated by preoperative CT scan. The following parameters were analyzed: tumor size and type, size of perifocal edema and whether the edema was fully included into treatment volume and finally the location of the recurrent tumor. The maximal distance between primary tumor and recurrent tumor was measured and also the distance from the border of the primary tumor to the distant border of edema for a visual analysis. RESULTS: Local limited volume irradiation was sufficient since 73.9% of recurrences occurred within 2 cm distance from primary tumor and 93.5% of recurrences occurred completely within 3 cm distance from primary tumor. Regarding the distance between primary tumor and recurrent tumor and the time interval until appearance of recurrent tumor it was not of importance if perifocal edema was included completely into treatment volume or not. CONCLUSION: Limited volume irradiation of malignant glioma with a target volume 3 cm beyond that indicated by preoperative CT scan seems to be sufficient, since 93.5% of recurrences were completely within 3 cm distance from the margin of the tumor. Improvement of the results with larger treatment volumes are unlikely. Complete irradiation of perifocal edema was not found to be necessary.

Adolescent↗
PubMed2001

Morphological examination of the effects of defibrotide on experimentally induced bladder injury and its relation to interstitial cystitis.

This morphological study aims to investigate the effects of defibrotide, a deoxyribonucleic acid derivative drug with cytoprotective, immunosuppressive and vasorelaxant effects, on protamine sulfate induced bladder injury. Wistar albino female rats were catheterized and intravesically infused with phosphate buffered solution (control group) or, either protamine sulfate (bladder injury group) or protamine sulfate+defibrotide (bladder injury+defibrotide group) dissolved in phosphate buffered solution. The morphology of the urinary bladder was investigated using light and electron microscopy. The number of mast cells in the mucosa, mucosal alterations, intercellular junctions, surface topography and the glycosaminoglycan (GAG) layer as well as microvillus formation on the luminal surface were evaluated. In the bladder injury group, ulcerated areas, irregularity of the GAG layer, increased number of mast cells, vacuole formation, dilated perinuclear cistern, formation of pleomorphic and uniform microvilli and dilatations in the intercellular spaces in the urothelium were observed. In the bladder injury+defibrotide group a relatively normal urothelial topography, GAG layer and a few mast cells in the mucosa, some dilatations between the intercellular areas, less uniform microvilli, regular perinuclear cistern and tight junctions were observed. These results show that defibrotide can inhibit PS induced bladder damage.

Animals↗
PubMed2000

A new interference nail fixation for anterior cruciate ligament soft tissue grafts.

We present a new device for femoral and tibial fixation in anterior cruciate ligament reconstruction using soft tissue. We evaluated the method biomechanically in pullout tests using human cadaver knee joints. Fixation strengths ranged from 300 +/- 60 to 600 +/- 50 N (mean 400 +/- 50 N). This corresponds to loads in the graft during aggressive rehabilitation although cadaveric specimens were used. With respect to primary fixation strength this implant is a reasonable alternative for anterior cruciate ligament graft fixation.

Aged↗
PubMed2000

An unusual indication for surgical treatment of iliac artery aneurysm treated with stented graft previously.

A 70-year-old man was seen with an iliac artery aneurysm and this was treated by an intraluminal graft-stent device introduced through the femoral artery. After the procedure, patency of the artery was proved to be good with control angiography but the mass effect of the aneurysmal sac on the gastrointestinal system did not disappear and we replaced the aneurysmatic segment with a collagen coated graft. The patient then recovered without any complications and gastrointestinal symptoms.

Aged↗
PubMed1999

Treatment of osteochondral defects with tendon autografts in a dog knee model.

Tendon autograft was used for the treatment of osteochondral defects induced experimentally in dogs' knees. Osteochondral defects were created on the femoral condyles in both knees of five dogs. The tendon was harvested from the anterior cruris, and a knot was tied in the middle. Then two tunnels were bored in the medial condyle. The free ends of the tendon were individually inserted into the tunnels and pulled from the openings on the medial recessus side so that the knot itself sat within the osteochondral defect. The lateral condyle was left untreated for comparison. At 24 weeks postoperatively, the dogs were killed and macroscopical and histological examinations were performed. A congruous articular surface had formed, and the grafted tendon was bonded into the defect. The tendon was not degraded, and was covered with reparative tissue as seen microscopically. Despite weight-bearing being allowed in the early stages after the operation, no sign of degradation was noted in the tendon.

Animals↗
PubMed1999

Hydatid disease and massive cardiac involvement.

Cardiac hydatid cysts are rare and represent 0.5-2% of all cases. Cardiac localization of hydatid cysts usually occurs in adults. Diagnosis is difficult because of the long latency between infection and manifestation of the disease, and also symptoms are nonspecific. We present a case study of 13-year-old girl with lots of hydatid cysts localized in the neighbourhood of the inferior vena cava right atrium and the superior vena cava right pulmonary artery aorta and posterior portion of the left atrium and the left ventricle, and the intramyocardium of the posterior wall of the left ventricle. An abdominal computed tomography scan showed a solitary cyst in the right posterior lobe of the liver. Following albendazole therapy for 3 weeks, she was operated on without cardiopulmonary bypass. Numerous alive and dead cysts were removed. Hepatic cysts were drained by percutaneous ultrasonography guided aspiration technique after surgery. On the 8th postoperative day, she was discharged while she was still on albendazole therapy.

Adolescent↗
PubMed1999

Cardiopulmonary bypass technique for treatment of renal cell carcinoma extending into the vena cava.

Cardiopulmonary bypass (CPB) is a unique technique used widely for renal cell carcinoma patients showing inferior vena cava invasion. We used a modification of CPB technique for 2 patients. These patients were managed with CPB without cross clamping and so without cold potassium cardioplegia. The primary tumor was a renal cell carcinoma propagating into the inferior vena cava and going into the right atrium as a thrombus in both patients. As a surgical procedure the urology team did nephrectomy and then with our clinical techniques we used CPB to cool the patients to 20 degrees C and decreased the flow to 500 ml/min/m2. The heart went into spontaneous ventricular fibrillation without using cross clamping and cardioplegia. Then we did atrial and inferior vena caval thrombectomy in a bloodless and visible operation field within a safe time interval. The aim of using this technique is to prevent myocardial injury and to protect the brain from hypoxia by using this low flow technique. This method can be used safely for the management of renal cell carcinomas and for some retroperitoneal malignancies associated with vena caval and atrial involvement.

Carcinoma, Renal Cell↗
PubMed1998

Anomalous digital nerve loop: a case report.

In this case, a digital nerve loop was observed during the dissection of the digital nerves to the third web space; the common digital artery was passing through this loop. This rare case is presented and its importance is discussed.

Adult↗
PubMed1998

Simultaneous radiochemotherapy versus radiotherapy alone in advanced head and neck cancer: a randomized multicenter study.

PURPOSE: A prospective randomized multicenter trial was performed to evaluate the contribution of simultaneously administered chemotherapy (CT) and radiotherapy (RT) in previously untreated patients with unresectable stage III/IV head and neck cancer. PATIENTS AND METHODS: Patients with locoregionally advanced head and neck cancer were treated either with RT alone (arm A) or simultaneous RT plus CT (RCT; arm B). RT was identical in both arms and administered in three courses with 13 fractions of 1.8 Gy each twice daily. During one course, from day 3 to 11, 23.4 Gy was delivered. In arm B, cisplatin (CDDP) 60 mg/m2, fluorouracil (5-FU) 350 mg/m2 by intravenous (i.v.) bolus, and leucovorin (LV) 50 mg/m2 by i.v. bolus were given on day 2, and 5-FU 350 mg/m2/24 hour by continuous infusion and LV 100 mg/m2/24 hours by continuous infusion were given from day 2 to 5. Treatment was repeated on days 22 and 44; a total RT dose of 70.2 Gy was administered. Treatment breaks were scheduled from days 12 to 21 and days 34 to 43. RESULTS: From 1989 to 1993, 298 patients were enrolled and 270 patients were assessable. Acute mucositis grade 3 or 4 was more frequent in arm B (38%) than in arm A (16%) (P < .001). Total treatment time was significantly longer in arm B than in arm A (P < .001) due to prolonged breaks. According to hematologic toxicity, scheduled drug doses were given in 74% of patients for the second course and 46% for the third course. The 3-year overall survival rate was 24% in arm A and 48% in arm B (P < .0003). The 3-year locoregional control rate was 17% in arm A and 36% in arm B (P < .004). Both arms showed similar distant failure patterns (arm A, 13 of 140; arm B, 12 of 130). Serious late side effects were not significantly different between treatment arms (arm A, 6.4%; arm B, 10%; not significant). CONCLUSION: Concomitant CT offered improved disease control and survival in advanced head and neck cancer patients. Due to increased acute toxicity, more supportive care is demanded when CT is given simultaneously. Increased total treatment time does not exert a negative impact on outcome in this combined modality regimen.

Adult↗
PubMed1997

Augmentation of vincristine cytotoxicity by megestrol acetate.

PURPOSE: To determine the effect of a semisynthetic progesterone, megestrol acetate (MA), on the cytotoxicity of various chemotherapeutic agents including vincristine, doxorubicin, actinomycin-D, taxol, vinblastine and colchicine in cell lines with or without P-gp expression. METHODS: Three cell lines with high P-gp expression (two colon cancer and one leukemia), and a control cell line with no P-gp expression were exposed to chemotherapeutic agents in the presence or absence of MA and drug sensitivity was determined using the MTT colorimetric assay. P-gp-170 expression was detected by flow cytometry using JSB-1 monoclonal antibody and the functionality of MDR expression was tested by rhodamine-123 uptake studies. In vitro drug accumulation studies were performed using [3H]-vincristine. The results were subjected to paired t-test analysis and 95% confidence intervals were determined in cytotoxicity tests. RESULTS: MA augmented the cytotoxicity of vincristine, but not doxorubicin, actinomycin-D, taxol, vinblastine or colchicine in the three P-gp-expressing cell lines, whereas verapamil augmented the cytotoxicity of doxorubicin and vincristine. MA did not augment the cytotoxicity of vincristine in the P-gp-negative HUT-102 cell line. CONCLUSION: MA augmented vincristine cytotoxicity in P-gp-expressing cell lines. However, this phenomenon did not occur with the other classic MDR drugs. Therefore, the augmentation of vincristine cytotoxicity by MA can be explained either by involvement of a different mechanism that coexists with the mdr-1 phenotype or by the presence of a different affinity or binding site on the P-gp molecule for MA compared to that for the other classic MDR drugs and verapamil.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed1995

[Reconstruction of the distal lower extremity defects with distal pedicled fasciocutaneous flaps].

Soft-tissue coverage of defects in the distal lower extremity has its limitations because of minimal blood supply to the skin and the thin muscle layer. Split-thickness skin grafting is impossible in cases of defects of tendons or bones. Local flaps are applicable only for smaller defects. With the cross-leg flaps, it is necessary to immobilize the patient for a long time. Special microsurgical technique and knowledge are needed for the free flaps. Fasciocutaneous flaps of the lower extremity after Donski and Fodgestam are simpler and safer than the other methods. From 1987 to 1992, this method was successfully used on 15 patients in the Department of Plastic Surgery of Sişli Etfal Hospital in Istanbul. In the two-thirds of those patients, accidents were the cause of the defects. The advantages of this methods are: simpler technique, larger flap-surface, earlier mobilisation of patients, better adaptation of the flap to its neighbourhood regarding colour and thickness.

Adolescent↗
PubMed1994

Leiomyosarcoma of the base of the tongue treated with radiotherapy: a case report.

Soft tissue sarcomas of the oral cavity are uncommon malignancies; those of smooth-muscle origin are extremely rare. The world literature reveals about 80 leiomyomas and 26 cases of leiomyosarcoma. Only 4 of the cases with leiomyosarcoma occurred in the tongue. This report of leiomyosarcoma of the base and dorsum of the tongue adds 1 case which was primarily treated with irradiation and achieved an excellent response. A 1.5-year follow-up after radiation-therapy is included and a review of the literature is presented.

Aged↗