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F Yildiz

Publications and source records attributed to F Yildiz.

At least 37 records · Page 2Linked to original sources
PubMed2000

Paclitaxel exposure time determines the nature of the interaction with radiation in HeLa cells. the role of apoptosis.

The purpose of the present study was to investigate further the mechanisms underlying subadditive and superadditive interactions of radiation and paclitaxel treatments in vitro. The protocol studied was a fixed radiation treatment (7 Gy) followed either immediately or after a 10 h delay by paclitaxel treatment. Paclitaxel treatment was exposure to either a fixed dose of paclitaxel (10 nM) for varying time intervals up to 25 h, or varying doses of paclitaxel up to 20 nM for a fixed exposure time of 24 h. The cells used were HeLa. Cell survival was assessed by colony forming ability and apoptosis was measured by flow cytometry. The results show that when the paclitaxel exposure time was 24 h superadditive interactions were observed at all paclitaxel doses. A reasonable correlation between surviving fraction as measured by colony forming ability and apoptosis in the attached cells at the end of paclitaxel treatment was observed. The nature of the interaction of radiation and subsequent paclitaxel treatment is critically dependent on the duration of the paclitaxel treatment.

Antineoplastic Agents, Phytogenic↗
PubMed2000

Inhaled corticosteroids may reduce neutrophilic inflammation in patients with stable chronic obstructive pulmonary disease.

BACKGROUND: Although both inhaled and oral corticosteroids have anti-inflammatory effects causing improvement in clinical symptoms and spirometry in the treatment of asthma, the role of corticosteroids in the management of chronic obstructive pulmonary disease (COPD) is controversial. OBJECTIVE: To evaluate the effects of inhaled corticosteroids on sputum neutrophilia in clinically stable COPD patients. METHODS: In total, 18 patients were enrolled in the study. During 2 months, 9 patients in group A inhaled fluticasone propionate (FP) 500 microg 3 times daily. In group B 9 patients received placebo. All of the patients continued to inhale both salbutamol and ipratropium bromide. In 9 patients, sustained-released theophylline was also administered. Blood samples, spirometric tests, blood gas analyses, and either spontaneous or induced sputum cultures were evaluated on entry into the study, after a 2 months of treatment and following the 6-week washout period. RESULTS: After the 2-month FP treatment, no significant changes in the number of peripheral blood neutrophils, blood gas and spirometry data were observed in both groups. In group A, the total cell number and the number of neutrophils decreased from a mean of 3. 4 +/- 1.3 x 10(6) cells/g and 0.6 +/- 0.3 x 10(6) neutrophils/g on entry into study to 1.9 +/- 0.6 x 10(6) cells/g and 0.02 +/- 0.01 x 10(6) neutrophils/g after 8-week treatment with FP, returning to 3.3 +/- 1.1 x 10(6) cells/g and 0.5 +/- 0.3 x 10(6) neutrophils/g following the washout period. The percentages of neutrophils were 55. 6 and 77.9% in groups A and B after 2 months of FP treatment. There was no significant change in group B values during the study. CONCLUSION: These data suggest that neutrophilic inflammation in sputum may be decreased by inhaled corticosteroids in clinically stable COPD patients.

Administration, Inhalation↗
PubMed2000

Sirenomelia with esophageal atresia.

Sirenomelia, is a rare fatal condition characterized by fusion of the lower extremities. It has been suggested that sirenomelia is a severe form of caudal regression syndrome complex for which the pathogenesis is controversial. Our case is a sirenomelia associated with esophageal atresia and tracheoesophageal fistula. In the literature, it has been pointed out that the VATER association may represent a less severe form of sirenomelia but no sirenomelia case associated with esophageal atresia and tracheoesophageal fistula has been found. Finally, we detected a single large artery which diverts the blood of the embryo's caudal part to the placenta with the detailed autopsy especially with focusing on the abdominal vasculature. This vascular steal is thought to be the main pathogenic mechanism of the condition.

Abdomen↗
PubMed1999

Comparison of AJCC 1988 and 1997 classifications for nasopharyngeal carcinoma. American Joint Committee on Cancer.

PURPOSE: A comparison of American Joint Committee on Cancer (AJCC) 1988 and 1997 nasopharyngeal carcinoma (NPC) classifications was made in terms of patient distribution and efficacy in predicting prognosis. METHODS AND MATERIALS: Between 1993-1997, 90 patients (64 M, 26 F) with non-metastatic NPC were treated. The mean age was 42.02 (range: 9-82) years old. Histopathological diagnosis was WHO 2 and 3 in 83 (92.2%) patients. All patients were prospectively staged using AJCC 1988 and modified Ho's classifications (1989) and these data were stored in a computer database. Retrieval of this information enabled us to restage patients according to the AJCC 1997. Median follow-up was 38 months. RESULTS: According to the AJCC 1988 there were 2 (2.2%), 6 (6.7%), 13 (14.4%), and 69 (76.7%) patients in Stage I, II, III and IV, respectively. Same figures were 8 (8.8%), 21 (23.3%), 26 (28.9%), and 35 (38.8%), according to AJCC 1997. Three year overall survival (OS) rates were 100%, 100%, 67%, and 62% for patients Stage I, II, III, and IV according to the AJCC 1988 and 100%, 72%, 65%, and 55%, (I vs. IV; p = 0.03, I vs. III; p = 0.05) respectively, according to the AJCC 1997. Three year loco-regional relapse free survival (LRRFS) rates were 50%, 100%, 100%, and 83% (I vs. III; p = 0.03) for patients in Stage I, II, III, and IV according to the AJCC 1988. Same figures were 88%, 90%, 89%, and 85% according to the AJCC 1997. Three year distant metastasis free survival (DMFS) rates were 100%, 100%, 82%, and 67% for patients in Stage I, II, III, and IV according to the AJCC 1988. Same figures were 100%, 74%, 80%, and 57% (I vs. IV; p = 0.03) according to the AJCC 1997. We did not observe any significant difference in LRRFS among T stages for both staging system and the N stage was the primary determinant for DMFS in both systems. CONCLUSIONS: We observed a better patient distribution with AJCC 1997 comparing to AJCC 1988. The new classification also attained better statistical significances among stages in the OS and DMFS rates.

Adolescent↗
PubMed1999

Multifocal bone tuberculosis presenting as a breast mass: CT and MRI findings.

Chest wall involvement is an uncommon manifestation of musculoskeletal tuberculosis. We present computed tomography and magnetic resonance imaging findings in a case with multifocal musculoskeletal tuberculosis presenting as a breast mass. These radiological modalities are not diagnostic without histopathological confirmation, but they are valuable guides to surgery in defining the extent of disease involvement.

Adolescent↗
PubMed1999

Color stability of denture base acrylic resins in three food colorants.

STATEMENT OF PROBLEM: Three commonly used artificial dyes in food technology are erythrosine, tartrazine, and sunset yellow. PURPOSE: The color stability of 5 commercially available denture base acrylic resins (QC-20, Meliodent, Trevalon, Trevalon High, and Lucitone) was studied in vitro. METHODS: The specimens were exposed to 3% erythrosine, tartrazine, and sunset yellow solutions at 23 degrees C +/- 1 degrees C. Color changes were determined with a computer-controlled spectrophotometer. Five specimens from each material were processed, and initial color measurements were made after 1, 3, and 6 months of exposure to the staining solutions. Finally, the color stability was quantitatively measured again, and color differences (DeltaE) were calculated. RESULTS: For the observations made in 1, 3, and 6 months intervals, the specimens that exhibited the least color change were in the sunset yellow solution. The greatest color changes observed according to the National Bureau of Standards unit system were Lucitone (2.71) in erythrosine solution, Lucitone (2.54), QC-20 (1.71) in tartrazine solution, and QC-20 (1.66) in sunset yellow solution. The changes in the other acrylic resins in the 3 solutions were slight and at trace level. CONCLUSIONS: All materials tested were acceptable from the standpoint of color stability for long-term exposure to these food colorants.

Acrylic Resins↗
PubMed1999

Radiotherapy in the management of giant pituitary adenomas.

BACKGROUND AND PURPOSE: The description of giant pituitary adenoma is not clear yet. In this study we tried to identify which adenomas can be defined as giant pituitary adenomas when tumor control and progression free survival (PFS) are taken as end points and we also tried to evaluate prognostic factors other than tumor size. MATERIALS AND METHODS: Between January 1981 and December 1997, 74 patients with pituitary macroadenomas more than 2 cm in size were treated. Of these 30 had tumors of more than 4 cm, while 44 patients were with tumors of 2-4 cm. Two patients received primary radiotherapy, while 72 were treated postoperatively. In the postoperative group, 52 patients underwent immediate radiotherapy after surgery and 20 were treated with irradiation after regrowth or progression of the tumor after initial surgery. The mean and median tumor doses were 5518 and 5425 cGy, respectively. RESULTS: Overall primary tumor control rate was 84%. The local control rates among patients with tumors more than 4 cm and among patients with tumors 2-4 cm after radiotherapy were 73 and 91%, respectively. PFS was 65% for patients who had a tumor size of more than 4 cm and 87% for the patients with tumor size of 2-4 cm (P = 0.09). Young age (<20) and tumors of unclassified histology were the bad prognostic factors. Six months after radiotherapy normalisation or improvement in hormonal hypersecretion and visual field and acuity deficits were 82 and 63%, respectively. CONCLUSION: Tumors more than 4 cm in size may be more convenient for the definition of 'giant pituitary adenoma' when tumor control and PFS are taken as the end points.

Adenoma↗
PubMed1998

Establishment and characterization of a human glioblastoma multiforme cell line.

Cell lines provide a useful system for further understanding the biology of glioblastoma multiforme. In this study, a new glioblastoma multiforme cell line, GATAGM-96 (Gulhane Askeri Tip Akademisi-Gliblastoma Multiforme-96), was established from a tumor specimen removed from an 80-year-old male patient who underwent surgery for intracranial tumor. Morphologic examination, immunocytochemical staining, growth kinetics, and karyotypic characteristics of this cell line were studied. The cytoskeleton was positive for neuron-specific enolase, vimentin, and neurofilament, and it was negative for glial fibrillary acidic protein, S-100 protein, p53 protein, epidermal growth factor, and transforming growth factor alpha. Growth kinetic studies demonstrated an approximate population doubling time of 38 to 42 h and a colony forming efficiency of 83.3%. The karyotype of the cells demonstrated it as hyperdiploid, with a large subpopulation of polyploid cells. There were numerous structural and numerical chromosome aberrations; most of them were present as clonal events. The phenotypic and chromosomal features detailed on the GATAGM-96 cell line should make it a useful addition to the cell lines currently available for in vitro and in vivo studies of glioblastoma multiforme.

Aged↗
PubMed1998

The influence of dose per fraction on the pathogenesis of radiation nephropathy.

Both kidneys of male Wistar rats were irradiated with either a 10-Gy single dose or 26 Gy at a rate of 2 Gy per fraction per day. Serum blood urea nitrogen (BUN), creatinine and blood haematocrit levels were assessed prior to radiotherapy and at intervals of 8 weeks thereafter. A subset of animals from each dose group were killed at 4, 8, 16 and 24 weeks and both kidneys of each animal were examined by electron microscopy. In both dose groups a significant increase in BUN and creatinine levels, together with a decrease in haematocrit level, was observed at 16 weeks, and this was followed by an apparent improvement at 24 weeks. There was no statistical difference in these responses between the two groups. The morphological changes in both dose groups were essentially similar, but differed in severity. At 4 weeks after irradiation glomerular and proximal tubular injury were observed in both groups. A marked increase of glomerular and tubular injury in the 10-Gy dose group, without any apparent progression in the 26-Gy dose group, was detected at 8 weeks. By 16 weeks a noticeable improvement in both tubular and glomerular lesions (especially in the 10-Gy dose group) was observed. No apparent difference from the 16th week of evaluation was found at 24 weeks. These findings indicate that there is some recovery in kidney after irradiation, but the extent of the recovery process is somewhat limited.

Analysis of Variance↗
PubMed1997

Kaposi's sarcoma: the efficacy of a single fraction of 800 cGy.

BACKGROUND: Although Kaposi's sarcoma is the most common neoplasm in association with AIDS, classic Kaposi's sarcoma is rare. The best treatment modality is still unclear. METHODS: Between December 1993 and December 1995, 42 fields in 12 patients with Kaposi's sarcoma were treated at our department. Only 3 patients had a history of renal transplantation and immunosuppressive treatment. A single dose of 800 cGy with 4-6 MeV electron beams was delivered to all patients. RESULTS: Complete response rates at the 1st, 6th and 12th months after treatment were 45.2, 62 and 89.7%, respectively. Side effects included various degrees of hyperpigmentation and mild edema and fibrosis in 1 patient. CONCLUSION: Our results suggest that a single application of 800 cGy is as effective as a more protracted course of radiotherapy with a comparable complication rate.

Adult↗
PubMed1989

[Uvulopalatopharyngoplasty without complications: a Fujita complication].

In 17 illustrations, a modification of Fujita's technique of UPPP is presented. This operation consists of excising redundant velar tissues from the free margin of the soft palate, tonsillar pillars, and uvula without reducing the muscles of the velum. In addition, the uvula muscle is almost completely preserved. Seventy patients, with habitual snoring or with obstructive sleep apnea syndrome, who underwent this surgery were followed-up from six to 24 months and did not show any palatal insufficiency with air and liquid escape through the nose. Additional remarks are made concerning the difficulties encountered during intubation of 60 percent of patients with chronic rhonchopathy.

Follow-Up Studies↗
PubMed1984

Reduction of gastric acid secretion. The efficacy of pre-anaesthetic oral cimetidine in children.

Cimetidine 10 mg/kg orally was given at varying times from 60 to 240 minutes pre-operatively to 100 healthy children between the ages of 6 months and 14 years. Cimetidine proved to be most effective when given between 120 and 180 minutes before the induction of anaesthesia. All patients in this group had a gastric pH of more than 2.5 and the mean volume aspirated was also significantly lower than that in the control group. The average peak blood concentration after 10 mg/kg oral cimetidine in four healthy children was 3.25 micrograms/ml (range 1.20-4.80) and occurred 75 minutes after administration (range 60-120 minutes). In these patients the mean (SD) half-life of cimetidine was 138 (18) minutes. The reduction of gastric juice volume and acidity produced by 10 mg/kg oral cimetidine given 120-180 minutes prior to induction of anaesthesia has important clinical implications.

Adolescent↗
PubMed1983

Rectal and oral cimetidine for prophylaxis of aspiration pneumonitis in paediatric anaesthesia.

In a prospective randomized study, 60 children between 1 and 8 years of age in three groups received no premedication, 10 mg kg-1 cimetidine orally or 40 mg kg-1 cimetidine rectally for prophylaxis of acid aspiration syndrome 120-180 min before induction of anaesthesia. The pH of the stomach contents was above 2.5 in both cimetidine groups. The aspirated gastric volume was significantly reduced with rectal cimetidine compared to the other groups. Rectal cimetidine proved to be the more effective drug for prophylaxis of acid aspiration syndrome in paediatric anaesthesia.

Administration, Oral↗
PubMed1983

[Efficacy of cimetidine in the prevention of aspiration pneumonia in paediatric anaesthesia].

In a prospective controlled study 63% of 150 children without prophylaxis were at risk of aspiration pneumonia in case of aspiration or regurgitation. In a second trial 10 mg/kg cimetidine orally 120 to 180 minutes prior to induction of anaesthesia proved to be a very effective prophylaxis. In small children up to 15 kg rectal application of 40 mg/kg cimetidine was even more effective than 10 mg/kg orally in reducing gastric volume. Premedication with cimetidine may be a practicable method for reducing the risk of aspiration pneumonia in paediatric anaesthesia.

Adolescent↗
PubMed1983

[Preoperative phase of limited normovolemic hemodilution].

In 35 cases, the attempt is made to present hemodilution as an appropriate means of hepatitis prophylaxis and blood sparing in patients having to undergo selective orthopedic or oral surgery. Especially in hospitals which cannot afford the expensive methods of autotransfusion, this method which is easy to perform from the technical and practical point of view offers a possibility of markedly reducing the transfusion rate of whole blood. Taking into account possible contraindications, this method is to be considered in all patients undergoing selective surgery where the general condition of the patient is sufficient and a blood loss of 1000-1500 ml is not exceeded.

Adolescent↗