Network


Latest external collaboration on country level. Dive into details by clicking on the dots.

Hotspot


Dive into the research topics where Yıldırım Bayezıt Şakalar is active.

Publication


Featured researches published by Yıldırım Bayezıt Şakalar.


American Journal of Human Genetics | 2010

MASP1 mutations in patients with facial, umbilical, coccygeal, and auditory findings of Carnevale, Malpuech, OSA, and Michels syndromes.

Asli Sirmaci; Tom Walsh; Hatice Akay; Michail Spiliopoulos; Yıldırım Bayezıt Şakalar; Aylin Hasanefendioğlu-Bayrak; Duygu Duman; Amjad Farooq; Mary Claire King; Mustafa Tekin

Distinctive facial features consisting of hypertelorism, telecanthus, blepharophimosis, blepharoptosis, epicanthus inversus, periumbilical defects, and skeletal anomalies are seen in autosomal-recessive Carnevale, Malpuech, Michels, and oculo-skeletal-abdominal (OSA) syndromes. The gene or genes responsible for these syndromes were heretofore unknown. We report on three individuals from two consanguineous Turkish families with findings characteristic of these syndromes, including facial dysmorphism, periumbilical depression, mixed hearing loss, radioulnar synostosis, and coccygeal appendage. Homozygosity mapping yielded an autozygous region on chromosome 3q27 in both families. In one family, whole exome sequencing revealed a missense mutation, MASP1 c.2059G>A (p.G687R), that cosegregated with the phenotype. In the second family, Sanger sequencing of MASP1 revealed a nonsense mutation, MASP1 c.870G>A (p.W290X), that also cosegregated with the phenotype. Neither mutation was found in 192 Turkish controls or 1200 controls of various other ancestries. MASP1 encodes mannan-binding lectin serine protease 1. The two mutations occur in a MASP1 isoform that has been reported to process IGFBP-5, thereby playing a critical role in insulin growth factor availability during craniofacial and muscle development. These results implicate mutations of MASP1 as the cause of a human malformation syndrome and demonstrate the involvement of MASP1 in facial, umbilical, and ear development during the embryonic period.


Japanese Journal of Ophthalmology | 2004

Color Doppler Imaging of Ocular Hemodynamic Changes in BehÇet’s Disease

İhsan Çaça; Hasan NazaroĞlu; Kaan Ünlü; Sevin Soker Cakmak; Şeyhmus Ari; Yıldırım Bayezıt Şakalar

PurposeA prospective evaluation of the ocular blood flow velocity in patients with BehÇet’s disease was carried out to determine its changes.MethodsSubjects were divided into three groups: those with ocular involvement in BehÇet’s disease (group I), those without ocular involvement in BehÇet’s disease (group II), and a control group (group III). Twenty-seven eyes in group I and 28 eyes each in groups II and III were investigated. The blood flow in the central retinal artery (CRA), ophthalmic artery (OA), nasal posterior ciliary artery (NPCA), and the temporal posterior ciliary artery (TPCA) was measured using color Doppler ultrasonography (CDU) to determine the peak systolic velocity (PSV), end diastolic velocity (EDV), and resistivity index (RI). The mean blood flow velocity of the central retinal vein (CRV) was also measured. These results were then compared among the three groups of subjects.ResultsThe PSV values of CRA in groups I and II were found to be significantly lower than those in the control group (P ≪ 0.001, P = 0.018, respectively). The PSV values of CRA in group I were found to be significantly lower than those in group II (P ≪ 0.001). The EDV values of CRA in groups I and II were found to be significantly lower than those in the control group (P ≪ 0.001, P = 0.034, respectively). The EDV values of CRA in group I were significantly lower than those in group II (P = 0.041). The PSV values of OA in group I were significantly lower than those in the control group (P = 0.002). The EDV values of OA in group I were significantly lower than those values in group II or the control group (P = 0.001 and P = 0.037, respectively). The PSV values of NPCA in group I were significantly lower than those in the control group (P = 0.007). The PSV values of TPCA in groups I and II were significantly lower than those in the control group (P ≪ 0.001, P ≪ 0.001, respectively). The EDV values of TPCA in group I were significantly lower than those values in group II or the control group (P = 0.014 and P = 0.003, respectively). There were no significant differences in the mean blood flow values of the CRV among all three groups (P ≫ 0.05).ConclusionsThere are significant reductions in the blood flow values of the orbital arteries in patients with BehÇet’s disease, and they are more evident in those with ocular involvement. This might be the result of occlusive vasculitis, which is frequently seen in the retinal vessels of patients with BehÇet’s disease. Jpn J Ophthalmol 2004;48:101–105


Japanese Journal of Ophthalmology | 2004

Cutaneous Anthrax on Eyelids

İhsan Çaça; Sevin Soker Cakmak; Kaan Ünlü; Yıldırım Bayezıt Şakalar; Ali Kemal Kadiroĝlu

BackgroundOphthalmologists should be aware of the signs and symptoms of anthrax, although it is a rare disease in humans. We report our successful treatment of three patients with cutaneous lesions in the periorbital area.CasesIn this study, we report on the treatment of three female patients who were initially diagnosed as having preseptal cellulitis.ObservationsGram-positive robs were revealed in the microscopic examination of scrapings taken from the lesions. Bacillus anthracis was found in only two of the three scraping-material cultures. Intravenous penicillin G was administered in all cases. Black and necrotic eschar, which is characteristic of anthrax, developed on the eyelids of all three patients during treatment. At the final examinations of the patients after the completion of treatment, we recognized the development of cicatrisation, lagophthalmos, and slight ectropion in the upper eyelid of the first patient, and, in the second patient, restriction of upper eyelid movement and development of a corneal scar from exposure keratopathy and ectropion. The cutaneous lesions healed without any eyelid pathology in the third patient.ConclusionAlthough it is a rare disease in humans, anthrax should be considered in the differential diagnosis of preseptal and orbital cellulitis.


Current Therapeutic Research-clinical and Experimental | 2009

Comparison of mitomycin C and limbal-conjunctival autograft in the prevention of pterygial recurrence in Turkish patients: A one-year, randomized, assessor-masked, controlled trial.

Şeyhmus Ari; İhsan Çaça; Zennure Özdemir Yildiz; Yıldırım Bayezıt Şakalar; Eyup Dogan

BACKGROUND A pterygium is a fibrovascular overgrowth of degenerative bulbar conjunctival tissue that grows over the limbus onto the cornea. Although various approaches have been proposed for the treatment of pterygium, the common problem after these treatments is recurrence. OBJECTIVES The goals of this study were to compare the efficacy of mitomycin C (MMC) and limbal-conjunctival autograft (LCAU) in preventing recurrence of primary pterygia and to monitor long-term adverse effects (AEs). METHODS Patients undergoing pterygium surgery between February 2006 and May 2007 were assessed prospectively and randomly divided into 2 groups using a random number table. The MMC group underwent pterygium excision and received 0.02% MMC intraoperatively for 2 minutes. The LCAU group underwent pterygium excision and LCAU. Recurrence and AE rates of the 2 treatments were compared during the 1-year follow-up period. Assessors for pterygial recurrence were masked to treatment group. RESULTS One hundred thirteen eyes (57 patients in the MMC group and 56 patients in the LCAU group) were included in the study. Thirteen of the patients (7 in the MMC group and 6 in the LCAU group) were withdrawn due to irregular attendance at follow-up visits or lack of sufficient dose and duration for postoperative topical antibiotic and steroid administration; their data were excluded from analysis. Fifty patients (MMC group: 26 men, 24 women; mean [SD] age, 48.0 [12.3] years; age range, 30-73 years; LCAU group: 27 men, 23 women; mean age, 49.0 [12.6] years; age range, 28-71 years) in each group completed the study. The mean (SD) length of the pterygium across the limbus was similar in the MMC group and the LCAU group (4.18 [1.27] vs 4.07 [1.24] mm). The mean follow-up period was also similar in the 2 groups (16.0 [1.9] vs 15.0 [1.7] months). The rate of recurrence was significantly greater in the MMC group than in the LCAU group (10 [20.0%] vs 2 [4.0%] patients; P=0.035). Seven patients (14.0%) in the MMC group experienced AEs: conjunctival cyst (3 patients), symblepharon (2), conjunctival granuloma (1), and dellen (1). In the LCAU group, 1 patient (2.0%; P=0.032 vs MMC group) experienced permanent graft edema. All patients in the LCAU group experienced transient graft edema, with recovery occurring in 3 to 4 weeks. There were no intraoperative complications and there was no graft rejection. CONCLUSIONS Recurrence and postoperative AEs were less frequently observed in primary excision with LCAU than with MMC in these Turkish patients who completed the study. This study found that pterygium excision with LCAU was well tolerated and effective in these patients.


Türk Oftalmoloji Dergisi | 2010

Comparison of Different Methods for Measurement of Intraocular Pressure and Evaluation of Effect of Central Corneal Thickness on Measurement Results

Yıldırım Bayezıt Şakalar; Selahattin Uğur Keklikçi; Selahattin Balsak; Eyyüp Doğan; Kaan Ünlü


Türk Oftalmoloji Dergisi | 2010

Preseptal Cellulitis Related to Tick Infestation

Yıldırım Bayezıt Şakalar; Neval Berrin Arserim; Selahattin Uğur Keklikçi; Selahattin Balsak; Mehmet Fuat Alakus; Kaan Ünlü


Türk Oftalmoloji Dergisi | 2010

Retinal Nerve Fiber Layer Thickness and Features of the Optic Disc in Patients with Nonocular Behçet’s Disease

Yıldırım Bayezıt Şakalar; Selahattin Uğur Keklikçi; Sevin Soker Cakmak; Şeyhmus Ari; Seyfettin Erdem; Kaan Ünlü


Turkiye Klinikleri Journal of Ophthalmology | 2008

Kafa İçi Kanamalı Olgularda Retinal Kanamaların Araştırılması

Yıldırım Bayezıt Şakalar; Aslan Guzel; Selahattin Uğur Keklikçi; İhsan Çaça; Kaan Ünlü


Turkiye Klinikleri Journal of Ophthalmology | 2006

Çocukluk Dönemi Kataraktlarında Aynı Seansta Bilateral Katarakt Cerrahisi Sonuçları

İhsan Çaça; Kaan Ünlü; Ali Ayata; Yıldırım Bayezıt Şakalar; Şeyhmus Ari


Turkiye Klinikleri Journal of Ophthalmology | 2005

Pterjiumlu Olgularda Oküler Yüzey Değişiklikleri

İhsan Çaça; Hüseyin Büyükbayram; Kaan Ünlü; Şeyhmus Ari; Yıldırım Bayezıt Şakalar

Collaboration


Dive into the Yıldırım Bayezıt Şakalar's collaboration.

Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Researchain Logo
Decentralizing Knowledge