Biomedical subjects
Publications and source records attributed to S Ozkan.
Anetoderma is a rare disorder of cutaneous atrophy with loss of dermal elastic tissue. Secondary anetoderma is seen after a variety of dermatoses. We describe a 33-year-old woman with secondary anetoderma after generalized granuloma annulare lesions that were most pronounced on sun-exposed areas.
PURPOSE: To examine the use of optical coherence tomography (OCT) in evaluating anatomical changes after laser in situ keratomileusis (LASIK) and complications related to the interface and corneal flap. SETTING: Istanbul University Eye Research Center and Department of Ophthalmology, Cerrahpasa Medical School, Istanbul, Turkey. METHODS: Eleven eyes of 11 patients who had myopic LASIK were included in the study. Mean age of the 7 men and 4 women was 29.4 years +/- 6.9 (SD). Cases analyzed included uneventful LASIK (4 eyes), epithelial ingrowth (5 eyes), and flap striae (2 eyes). Corneas were examined by OCT (Humphrey Systems). RESULTS: Optical coherence tomography resolved corneal flap and residual stromal layers in all cases. The mean thickness of the corneal flap and residual stroma was 138.2 +/- 16.5 microm and 321.7 +/- 32.1 microm, respectively. Interface between the corneal flap and residual stroma was shown by OCT. Optical coherence tomography revealed that the eye with flap striae had flap displacement undetected by biomicroscopy. Epithelial ingrowth was shown as a highly reflective area. CONCLUSION: Optical coherence tomography appears to be a promising method for evaluating anatomical changes in the cornea after LASIK.
A 23-year-old woman had bilateral myopic laser in situ keratomileusis (LASIK). Two months postoperatively, she reported decreased visual acuity. Biomicroscopic examination revealed a corneal epithelial iron ring around the central keratectasia on both corneas. The appearance of the ring pattern was similar to the iron deposits of the Fleischer ring of keratoconus.
PURPOSE: To evaluate the reproducibility of flap thickness during laser in situ keratomileusis (LASIK) and to analyze the effect of preoperative central corneal thickness and corneal keratometric power on flap thickness. SETTING: Department of Ophthalmology, Cerrahpasa Medical School, Istanbul, Turkey. METHODS: One hundred forty eyes with a mean preoperative pachymetry of 554.4 microm +/- 36.3 (SD) and a mean keratometry of 43.5 +/- 1.9 diopters had LASIK using the Hansatome automated microkeratome (Bausch & Lomb Surgical) and a 193 nm argon-fluoride excimer laser (Summit SVS Apex Plus). The 180 microm microkeratome plate was used in all procedures. Corneal thickness was measured with an ultrasonic pachymeter (Advent, Mentor O&O Inc.) before and during the flap procedure, and the difference was taken as flap thickness. The data were analyzed using a 1-tailed t test and Pearson correlation coefficient. RESULTS: The mean flap thickness was 120. 8 +/- 26.3 microm. There was a low correlation between baseline central corneal thickness and corneal flap thickness (P =.6, r = 0. 046). There was no correlation between preoperative keratometry and flap thickness (P =.01, r = 0.203). CONCLUSIONS: The Hansatome microkeratome does not always produce a corneal flap of the intended thickness. Factors other than keratometry and pachymetry must affect flap thickness.
BACKGROUND: Borrelia burgdorferi (Bb) infection has been implicated in the development of morphea and lichen sclerosus; however, conflicting results have been reported with different investigational methods from different regions. We looked for evidence of Bb in patients with morphea and lichen sclerosus by polymerase chain reaction (PCR) analysis of of skin biopsy samples. METHODS: Formalin-fixed, paraffin-embedded skin biopsy samples from 10 patients with morphea and 12 patients with lichen sclerosus were investigated by PCR analysis for the presence of Bb. RESULTS: The presence of Bb DNA was demonstrated in three of 10 patients with morphea and six of 12 patients with lichen sclerosus by nested PCR. CONCLUSIONS: The data obtained in this study suggest that Bb may play a role in the etiopathogenesis of both morphea and lichen sclerosus at least in the western parts of Turkey.
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OBJECTIVE: To identify the risk factors for falling after stroke, to establish the relation with lesion localisation, and to evaluate the incidence of falling. METHODS: The falling history and the mood of 293 patients with stroke were investigated by a standard questionnaire. Other information (time since stroke, risk factors, and CT) about patients was obtained from their hospital records. RESULTS: Increasing age, depression, and heart disease were significant risk factors for falling (heart disease had a negative influence). A right hemispheric infarct was significantly more common among the falling group. CONCLUSION: This study suggests clues for possible modifications of the management of patients with stroke during the recovery period.
A 73-year-old man with porokeratosis palmaris, plantaris et disseminata is presented. He had punctate, guttate and annular hyperkeratotic papular lesions widespread on his body with thorn-like hyperkeratosis on the palms and soles. Lesional skin did not show mutations of TP53 exons 5-6, 7, 8.
BACKGROUND: Myocardial involvement in Behçet's disease has been reported to be relatively rare. OBJECTIVE: To evaluate myocardial involvement noninvasively in patients with Behçet's disease by measuring signal-averaged electrocardiography (SAECG), QT dispersion and heart rate variability (HRV). PATIENTS AND METHODS: The study group comprised 28 eligible patients (16 male, mean age 37+/-13 years) of 33 patients with Behçet's disease, and 25 age- and sex-matched control subjects. RESULTS: The echocardiographic left ventricular measurements were within normal limits and similar in both groups except the E/A ratio, which was significantly lower in patients with the disease than in control patients. Minimal pericardial effusion was detected in four patients. Considering the SAECG recordings, values of root mean square voltage in the last 40 ms were 30+/-18 microV and 38+/-18 microV in patients with Behçet's disease and in the control group, respectively. The number of cases with a value less than 20 microV was seven (25%) and one (4%) in the same groups, respectively. Both QT dispersion and the corrected QT interval dispersion were significantly increased in patients with Behçet's disease compared with the control patients (50.2+/-16.6 versus 20.4+/-18.8, P<0.01). Although all HRV measures appeared to be decreased in the Behçet's group, only the standard deviation of all filtered RR intervals in the entire 24 h ECG recordings and the percentage of differences between adjacent filtered RR intervals that are greater than 50 ms for the whole analysis values differed significantly between the groups (P<0.05). No significant difference was observed in frequency domain parameters. In the Holter ECG recording, grade 2 or greater premature ventricular complexes were observed in seven patients from the Behçet's group (25%) but in only one subject from the control group (4%) (P<0.05). CONCLUSIONS: Patients with Behçet's disease appeared to have significantly increased QT dispersion, a left ventricular diastolic dysfunction pattern in echocardiography, a high incidence of positive late potentials and more complex ventricular arrhythmias, suggesting myocardial involvement and the existence of an arrhythmogenic substrate, whereas the HRV measures do not suggest a clear autonomic abnormality in Behçet's disease.
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The aetiology of Ménière's disease still remains unknown and its therapy is therefore empirical. As a result of immunological abnormalities demonstrated, steroids are commonly used in Ménière's disease. The place of topical steroids is still controversial. In this investigation topical dexamethasone is applied for three months through a ventilation tube in patients with intractable vertigo. The results showed that this treatment controls vertigo in 72 per cent of cases. No patient was worse than before treatment. Only in 17 per cent of the patients was there an increase in hearing level. When compared to the reports which used only tympanostomy tubes, this procedure seems to have a placebo effect with minimal harmful effects. It appears that transtympanic dexamethasone application is a good alternative to vestibular nerve section. Topical treatment may be sufficient in most patients. Systemic treatment may be used in patients where topical treatment fails.
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1. Heterozygous naked neck (Na/na+) birds and their normally feathered counterparts (na+/na+) were fed from 0 to 7 weeks on 3 diets differing in methionine concentrations. From 0 to 3 and 3 to 7 weeks, respectively, the concentrations were: low containing 4.3 and 3.3 g/kg; optimum containing 5.0 and 3.8 g/kg and; high with 5.7 and 4.4 g/kg under spring (optimum ambient temperature) and summer conditions (high ambient temperature). Performance, carcase characteristics and breast meat chemical composition were determined. 2. Summer rearing resulted in a decrease in body weight, body weight gain, food consumption, and yields of carcase and breast. The summer temperature effect was more pronounced in males. Under summer temperatures, the protein content of the breast decreased while the fat content increased compared to birds reared in spring. 3. By 7 weeks of age, both genotypes reached similar body weights in the spring experiment while, in summer Na/na+ birds were 3.3% heavier and gained more in the period from 3 to 7 weeks than na+/na+ birds. Carcase and breast yields of Na/na+ birds were greater than in na+/na+ birds. 3. Second order polynomial coefficients of the dietary methionine effect were found to be significant for body weight at 3 and 7 weeks. Daily body weight gain between 3 and 7 weeks was linearly affected by the dietary methionine concentration. There was no interaction between genotype and methionine. 4. Methionine had no significant effect on carcase yield. Second order polynomial coefficients of the dietary methionine effect were found to be significant for breast yield while the methionine effect on abdominal fat was linear. Na/na+ females fed on the low methionine diet had lower protein content than the Na/na+ males. 5. It is concluded that the methionine requirement of Na/na+ birds did not differ from that of their normally feathered counterparts under either spring or summer ambient temperature conditions.
A study was conducted to evaluate the effect of genotype by environment (G x E) interaction on the performance of commercial broilers. Temperate and hot environments were established by making use of the natural climatic differences between spring and summer in western Turkey. The experimental population was produced by a full-pedigree, randomly assigned mating scheme consisting of 29 sires and five dams per sire. The sires were considered genotypes, and the G x E interaction was evaluated by regressing sire breeding values in summer on those estimated from their spring offspring. The correlation between the two seasons for weight gain from 0 to 4 wk of age was r = 0.26, significantly lower than rho = 1 (the expectation when there is no G x E interaction). This correlation was even negative (although not significantly lower than rho = 0) for weight gain (WG) from 4 to 7 wk of age and BW at 7 wk of age. Genotype by season ANOVA also revealed highly significant G x E interaction effects on all traits. These interactions suggest the presence of substantial genetic variation in the magnitude of heat tolerance. It appeared that this variation was not random, but rather related to growth potential, where genotypes that gain more weight in the spring tended to gain less weight under the hot conditions of summer.
PURPOSE: The purpose of this study was to compare the lactate dehydrogenase (LDH) activities in the tears of patients wearing different types of contact lenses with each other and to individuals who have never worn contact lenses (controls). METHODS: Tear LDH activities were determined in 13 normal subjects who had never worn contact lenses, 12 daily wear and ten extended wear soft contact lens wearers, and 14 daily wear and eight extended wear rigid gas permeable (RGP) contact lens wearers(Dk125). Tear samples were collected from all subjects at the same time of day from the inferior meniscus by using a microcapillary tube. The measurements were determined using a Sigma diagnostic LDH reagent and a spectrophotometer. RESULTS: There was no statistically significant difference in the LDH activities between soft and RGP contact lenses--used either as daily or extended wear--when compared with each other. However, individuals wearing extended wear soft contact lenses had significantly higher tear LDH activities than the control group. CONCLUSION: Tear LDH activity may be a useful method in evaluating the physiologic response of extended soft contact lens wear.
PURPOSE: To suggest a different method for diagnosing vesicoureteral reflux (VUR) in lieu of voiding cystourethrography (VCU), in order to prevent radiation exposure. MATERIALS AND METHODS: Fifty-two ureterorenal units of 26 patients were evaluated ultrasonographically for visualizing the renal collecting systems, both before and after filling up the bladder with saline infusion. Every patient also underwent evaluation with VCU. RESULTS: All patients with Grade 2 or higher degrees of VUR on VCU can be identified by ultrasound (USG). Overall sensitivity and specificity of this technique were 66.7% and 93.48%, respectively, in our patient group. CONCLUSION: After being diagnosed with VCU initially a VUR patient can be effectively followed up by USG in order to prevent radiation exposure. Considering the clinical management of a patient with Grade 1 VUR which could not be detected with USG, it is concluded that failure to detect Grade 1 VUR will not be a handicap.
Prostatic epithelium basically consists of secretory-luminal, basal and endocrine-paracrine cells. Immunohistochemical procedures are frequently used for showing the cells reflecting different differentiations. In this study, 40 prostatic tissue specimens submitted to the Department of Pathology of Inönü University, Research Hospital, between 1991 and 1996 were examined. Half of the cases were diagnosed as cancer and the other half had various benign lesions. Of the cases 22.5% (n = 9) were needle biopsy material whereas the remainder, 47.5% (n = 19), were from prostatectomy and 30% (n = 12) were transurethral resection of the prostate (TURP) specimens. High molecular weight anti-cytokeratin antibodies (HMW anti-cytokeratin) stained basal cells both in all normal prostatic tissue and benign prostatic lesions, but in the majority of cancers (70%, n = 14) negative immunoreactivity was seen. Nevertheless, in some of the cancer cases (30%, n = 6) basal cell anti-cytokeratin staining was shown. Negative immunoreactivity with HMW anti-cytokeratin is important in distinguishing between malignant and benign lesions, whereas positive staining is not every time in favour of benign lesions. With the usage of prostate specific antigen (PSA) it was seen that all of the malignant and benign prostatic lesions stained positively. Basal cells in hyperplastic glands were not stained with this stain. Irregular, and in some areas, intense (PSA) immunoreactivity is present in precancerous and malignant lesions. Endocrine cells, which are represented with Chromogranin-A (Chr-A) immunoreactivity and reflecting neuroendocrine differentiation, are present in 75% (n = 15) of benign lesions and in 50% (n = 10) of cancer cases. It was thought that the lesser number of these cells in neoplastic lesions in comparison to the non-tumoral lesions is correlated with the disorder of mechanism that regulates the cell growth. Both in neoplastic and non-tumoral tissues the prostatic epithelial cells showed the three markers, namely HMW anti-cytokeratin, PSA, and Chr-A, which may reflect the multidirectional differentiation of these cells from a pluripotent origin.