Biomedical subjects

Kivanc Gungor

Publications and source records attributed to Kivanc Gungor.

4 recordsLinked to original sources

PubMed2005

Cell division and cellular morphology of the chick retinal pigmented epithelial cells in culture: a time-lapse analysis.

OBJECTIVE: To investigate the patterns of cell division, movement and shape during early stages of development of the chick embryo retinal pigmented epithelial (RPE) cells and to evaluate the morphology of dissociated embryonic cells with regard to their proliferation capacity. METHODS: We conducted this study at the Department of Histology and Embryology, Celal Bayar University, Manisa, Turkey, between 2002 and 2003. We isolated the cells from chick embryos. We analyzed the images of the embryonic cells originated from neuroepithelia using a computer-based time-lapse acquisition system attached to a differential interference contrast microscope. RESULTS: Retinal pigmented epithelial cells, despite being dissociated, depict a colony-type growth. Cells in the periphery of the colony and those outside the colony showed a tendency to proliferate and migrate and retained contact with the neighboring cells during division. Characteristics of cytokinesis were separation from the neighboring cell while retaining an attachment point, became rounded, moved up and started to shake and ascend to disseminate to the substrate to complete the division. The round-up stage was non-significantly shorter when the cell was closer to the center of the colony. Cells that were in the periphery of, or outside the colony had a round-up time of over one hour while cytokinesis-to-adhesion time was around 5 minutes. However, when we found the cells in the center of the colony, the times were half-an-hour and 1.5 hours for the daughter cells, a 2-fold difference between daughter cells with regard to the duration of attachment. CONCLUSION: Cell division, migration and proliferation are complex procedures influenced by growth factors, cell adhesion, matrix molecules underneath and the signal mechanisms and can be studied in detail using time-lapse microscopy, immunohistochemistry and confocal microscopy.

Animals↗

PubMed2004

Effectiveness of retroequatorial recession surgery in congenital nystagmus.

OBJECTIVE: The aim of this retrospective study was to evaluate the effectiveness of the retroequatorial recession technique in the surgical treatment of nystagmus and associated strabismus. METHOD: The effect of large recessions of four horizontal extraocular muscles was analyzed qualitatively in seven patients with congenital nystagmus. RESULTS: The ages of the patients ranged between 12 and 42 years (mean, 21.5 years). Of the seven patients, four had motor and three had sensory nystagmus. Visual acuity increased in five (71.4%) patients. Planned recovery of associated strabismus was attained in six patients (85.7%). In five patients who had abnormal head position, the head positions and nystagmus intensities were found to be decreased. No postoperative complication, such as diplopia, was encountered. CONCLUSION: The retroequatorial recession technique is preferable in patients who have congenital nystagmus, especially in the presence of horizontal squint associated with low visual acuity, because of its success in increasing visual acuity and decreasing the amplitude of nystagmus, its reversibility, making posssible new operations in the future, as well as the absence of any significant complications.

Adolescent↗

PubMed2003

Ocular anterior segment pathologies and tear film changes in patients with psoriasis vulgaris.

Ocular manifestations in patients with psoriasis vulgaris have been investigated in only a small number of studies. Our purpose was to identify tear film function and ocular pathologies associated with psoriasis vulgaris in patients who had received neither oral retinoids nor phototherapy. We examined 62 eyes of 31 patients with psoriasis and 60 eyes of 30 age-and-sex matched healthy volunteers. In addition to complete ocular and dermatological examination, tear film function (i.e., tear secretion and tear film stability) were assessed by the Schirmer-I test, as well as by tear film break-up time. None of the controls had any ocular abnormalities, whereas 67.74% of patients with psoriasis had various anterior segment pathologies (P<0.00009). The most prevalent finding was chronic blepharoconjunctivitis (64.5%), as the only pathology (n=9) or in association with other findings, including nonspecific corneal opacities (n=4), cataract (n=3), both corneal opacities and cataract (n=2), and corneal pigment dispersion (n=2). The Schirmer-I test results revealed comparable mean values in the patient group (9.8+-4.2 mm) and in the controls (11.2+-3.7 mm; P=0.078). However, mean tear film break-up time was significantly shorter in the patients (7.2+-2.5 sec) than in the healthy persons (11.7+-3.1 sec; P=0.001). In agreement with some previous reports, our findings clearly demonstrated that early ocular involvement occurs in patients with psoriasis vulgaris, irrespective of the history of previous therapeutic modalities (e.g., retinoid therapy and phototherapy). Thus, the present findings are suggestive of the contributory role of primary etiologic factors of psoriasis in the pathogenesis of ocular changes in patients with psoriasis vulgaris.

Adolescent↗

PubMedDate not supplied

Angiotensin-converting enzyme insertion-deletion polymorphism in primary open-angle glaucoma.

PURPOSE: To investigate the hypothesis that primary open-angle glaucoma (POAG) is associated with a common insertion-deletion (I/D) polymorphism in the angiotensin-converting enzyme (ACE) gene. METHODS: ACE I/D polymorphism was investigated in a control group of healthy subjects (n = 101) and in a group of patients diagnosed with POAG (n = 104). Polymerase chain reaction detection of I/D polymorphism was used to determine the presence of the two ACE alleles in the groups. RESULTS: Neither the I/D genotype distributions nor the allele frequencies differed significantly between POAG and control subjects (DD genotype 34.6 vs. 39.6%; ID genotype 53.9 vs. 40.6%; II genotype 11.5 vs. 19.8%, p = 0.1; D allele 61.5 vs. 60%; I allele 38.5 vs. 40%, p = 0.8). CONCLUSION: We could not identify a possible association of the I/D polymorphism in the ACE gene with POAG, however further studies with larger patient numbers in different populations are required to clarify the role of ACE gene in susceptibility to POAG.

Female↗