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Zekeriya Tosun

Publications and source records attributed to Zekeriya Tosun.

At least 19 recordsLinked to original sources
PubMed2026

Mesenchymal Stem Cell-Derived Exosomes Combined With 3-Dimensional Hyaluronan-Based Scaffold Promote Tendon-to-Bone Tunnel Healing.

PURPOSE: Tendon-to-bone healing remains a major clinical challenge due to poor regenerative capacity at the enthesis. This study aimed to evaluate the effects of mesenchymal stem cell-derived exosomes combined with a 3-dimensional hyaluronan-based scaffold on graft healing within bone tunnels. This study was conducted in accordance with the ARRIVE (Animal Research: Reporting of In Vivo Experiments) guidelines. METHODS: A total of 128 tendon-bone models were created in 64 Sprague-Dawley rats, randomized into four groups: control, exosome-only, scaffold-only, and exosome-loaded scaffold. At weeks 4 and 8 postoperatively, samples were analyzed histologically (hematoxylin-eosin, Masson Trichrome), immunohistochemically (fibroblast growth factor 2, bone morphogenetic protein 2), and biomechanically (maximum failure load). RESULTS: At both time points, the exosome-loaded scaffold group demonstrated significantly enhanced vascularization, cellular activity, and collagen fiber continuity and parallelism compared to all other groups (P < .05). Fibroblast growth factor 2 and bone morphogenetic protein 2 expression levels were highest in the exosome-loaded scaffold group, indicating early activation of proregenerative pathways. Biomechanically, this group also exhibited the greatest maximum failure load (15.64 &#xb1; 0.86 N at week 4; 22.97 &#xb1; 2.86 N at week 8), suggesting superior tendon-to-bone integration. The exosome-only group showed delayed but comparable improvements by week 8. CONCLUSIONS: Combining mesenchymal stem cell-derived exosomes with a 3-dimensional hyaluronan-based polycaprolactone/tricalcium phosphate scaffold enhances early and sustained healing at the tendon-bone interface. This cell-free, biocompatible strategy significantly improves vascularization, growth factor expression, collagen organization, and mechanical strength. These findings support its potential as a clinically translatable approach for improving tendon-to-bone healing outcomes. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic V.

Animals↗
PubMed2006

Pyoderma gangrenosum in a battered child.

Pyoderma gangrenosum is an uncommon cutaneous ulceration, which continues to be a difficult disorder to diagnose and treat. A pediatric case of pyoderma gangrenosum with no associated systemic disorder is presented. The disease was precipitated by physical trauma. The disease was controlled with systemic corticosteroid therapy and then the wound was successfully covered with a split-thickness skin graft from the thigh without any healing problem at the donor site. Although pathergy is well described in the etiopathogenesis of the disease, this is the first case reported that was precipitated after physical assault.

Child↗
PubMed2005

A comparative study of the influence of smoking on skin flap survival in pregnant rats.

In this study, the effects of smoking on skin flap survival were evaluated. For purposes of comparison 12 female rats were divided into four groups. Group 1 comprised nonsmoker, nonpregnant rats; group 2 nonsmoker, pregnant rats; group 3 smoker, nonpregnant rats and group 4 smoker pregnant. On each subject a standard 4 x 10 cm McFarlane dorsal skin flap was raised. On the seventh day postoperatively, the flaps were traced on a transparent sheet marking off the necrotic areas. The area of skin flap necrosis was assessed by 'netcad' digital imaging analysis program. The area of skin flap viability in the pregnant groups was greater than in the nonpregnant groups. The nonsmoker pregnant group's flap viability was the highest and the smoker nonpregnant group's viability was the lowest. This result supports the conclusion that pregnancy enhances flap viability and produces some defensive factors against some of the adverse effects of smoking.

Animals↗
PubMed2005

Effects of isoflurane and sevoflurane on the survival of skin flaps in rats.

The effects of inhalational anaesthetic agents on survival of flaps are not well known. We investigated the effect of isoflurane and sevoflurane anaesthesia on survival of flaps using a caudally-based McFarlane skin flap in 20 male Wistar rats. Sevoflurane 1 minimum alveolar concentration (MAC) and isoflurane (1 MAC) in oxygen mixture was given to the animals. A 4 x10 cm caudally-based standard McFarlane flap was raised. There were no differences in any haemodynamic values or blood gases between the sevoflurane group and the isoflurane group. Skin flaps were assessed on the seventh day. The isoflurane group had a significantly smaller area of skin flap necrosis and an increased area of flap surviving than the sevoflurane group. We conclude that survival is significantly improved when isoflurane is used as the inhalational anaesthetic rather than sevoflurane.

Anesthesia↗
PubMed2005

Maxillofacial morphology in children with complete unilateral cleft lip and palate treated by one-stage simultaneous repair.

BACKGROUND: There is a common belief among the majority of surgeons occupied with cleft lip-cleft palate repair that early one-stage simultaneous repair of hard and soft palates affects maxillofacial development adversely. This proposition has not been proven with long-term clinical studies. In this study, the effects of one-stage repair on the maxillofacial development of children with complete unilateral cleft lip-cleft palate were investigated, and the results were compared with those of the cleft children treated with conventional two-stage repair. METHODS: The study was designed as follows. Group 1 consisted of 19 children (mean age, 85.4 +/- 12.8 months) treated with a one-stage procedure. In this group, cleft lip, palate, and alveolus were repaired simultaneously at a single surgical session in the first 10 months of life (mean age at time of surgery, 6.8 +/- 1.2 months). Group 2 consisted of 22 children (mean age, 90.1 +/- 13.0 months) treated in two stages as follows: lip repair was performed at a mean age of 4.8 +/- 1.0 months and palate repair was performed at a mean age of 14.6 +/- 2.0 months. The follow-up period was approximately 6.3 years for both study groups. Group 3 (control) consisted of 27 children (mean age, 87.1 +/- 11.7 months) without cleft who were matched for age. RESULTS: Compared with the control group, the children in both cleft groups revealed a greater maxillomandibular retrognathism, a more open palatal plane, larger anterior facial heights, and decreased posterior vertical maxillofacial heights. No significant difference was determined between study groups 1 and 2. CONCLUSIONS: Because both of the surgical treatment procedures give rise to similar maxillofacial development outcomes, regardless of the timing of surgery, the one-stage procedure offers several important advantages, such as less psychosocial trauma, low cost, and possibly an improvement in speech results because of less scarred palatal fields and the low rate of palatal fistula.

Cephalometry↗
PubMed2005

Delaying the reverse sural flap provides predictable results for complicated wounds in diabetic foot.

Defective wounds in diabetic foot are difficult to manage. Several studies reported the use of reverse sural flap in a small number of patients with varying success. We presented our experience with the reverse sural island flap (RSIF) in a series of 37 patients associated with diabetic foot using the delay procedure. The ages of the patients ranged between 36 and 73 years. We did not perform angiographic evaluation to determine the existence of vascular connections between the branches of the peroneal and posterior tibial artery; however, Doppler ultrasound evaluation was done to determine the patency of anterior and posterior tibial arteries, as well as lesser saphenous vein before the operation. The flaps were transferred using a 3-step delay procedure. While all the first and second steps of the operations were done under local anesthesia, the third steps were performed using general anesthesia in 12 and spinal anesthesia in 25 patients. All flaps survived except 4 showing partial necrosis due to venous insufficiency. Delaying the RSIF is a reliable procedure for diabetic foot skin defects.

Adult↗
PubMed2004

Experience with vaginoplasty.

We did 27 vaginoplasties (7 gracilis musculocutaneous flaps, 8 pudendal thigh flaps, 12 full-thickness skin grafts) during the period 1994-2000. The preoperative assessment and postoperative follow up were done in collaboration with the gynaecologists. All patients had vaginal agenesis. With the gracilis flaps we found it difficult to achieve an adequate blood supply. With pudendal thigh flaps we achieved perfect innervation and a good contour, but they did tend to be hairy. With full-thickness skin grafts the innervation was not perfect, but the contour was good. Having compared the three operations during a follow up period ranging from 1-5 years we think that the full-thickness skin graft gives the best results.

Adolescent↗
PubMed2003

Reconstruction of microform cleft lip.

Partial cleft of the orbicularis oris muscle without skin and mucosa can also be called "discontinuity of the orbicularis oris muscle" or "subepithelial cleft". Microform cleft lip or mini-cleft lip are better definitions. We present two women aged 25 and 29 years old who complained of vermilion notching, vertical depression on the upper lip, and asymmetry of lower lateral cartilage of the nose. The "discontinuity of the muscle" was found at operation in both cases and reconstructed successfully.

Adult↗