Mahmud Özkut

Thymoquinone accelerates new bone formation in the rapid maxillary expansion procedure

OBJECTIVE The aim of this study was to evaluate the effect of systemic thymoquinone (TQ) in a rat rapid maxillary expansion (RME) study. DESIGN Thirty-two Wistar albino rats were divided into 4 equal groups: only-expansion (OE), expansion plus TQ (TQ1 group, TQ given to the rats during their nursery phase and during the expansion and retention period), expansion plus TQ (TQ2 group, TQ given to the rats only during the retention period), and control group (no procedure done). Expansion appliances were placed on the maxillary incisors of all animals for 5days. The appliance was deactivated during the 12day retention period. The rats were sacrificed at the end of the retention period. Histomorphometric evaluation was carried out in order to compare the number of osteoclasts, osteoblasts, and capillaries, as well as the intensities of inflammatory cells, and new bone formation amongst the groups. RESULTS New bone formation, number of capillaries and the ratio of intensities of inflammatory cells in maxillary sutures was higher in the TQ groups than in the other groups. Statistical analysis also demonstrated that osteoblast and osteoclast numbers were also highest in the TQ1 group. CONCLUSION Histomorphometric analysis demonstrated that systemic use of thymoquinone may be effective in accelerating new bone formation in the RME procedure and that TQ may be beneficial in preventing relapse following the RME procedure.

Effects of Ginkgo biloba on experimental rapid maxillary expansion model: a histomorphometric study

OBJECTIVE We aimed to investigate the effect of systemic Ginkgo biloba in rapid maxillary expansion (RME). STUDY DESIGN We randomly divided 24 rats into 3 groups: expansion only (EO), expansion plus Ginkgo biloba (GB), and no expansion (NE). Expansion appliances were affixed to the maxillary incisors. After a 5-day expansion period, there was a consolidation period of 15 days, following which the rats were killed. Histomorphometric examination was performed to determine the number of osteoclasts, osteoblasts, and capillaries, the number and intensity of inflammatory cells, and new bone formation. RESULTS New bone formation, number of capillaries, and the ratio of inflammatory cells in maxillary sutures were higher in the GB group than in the other groups. Statistical analysis demonstrated that the GB group had more osteoblasts and osteoclasts than the other groups. CONCLUSIONS GB may hasten new bone regeneration in RME and prevent relapse after RME.

Effect of Pirfenidone on Vascular Proliferation, Inflammation and Fibrosis in an Abdominal Adhesion Rat Model.

ABSTRACT Aim: To study the efficacy of pirfenidone for prevention of postoperative adhesion formation in an adhesion rat model. Materials and Methods: Eighteen female Wistar rats were subjected to right-sided parietal peritoneum and right uterine horn adhesion model. Rats were randomized into three groups: group 1 (control) (closure of midline abdominal incision without any agent administration), group 2 (closure of incision after intraperitoneal administration of pirfenidone), and group 3 (closure of incision and only oral administration of pirfenidone for 14 days). Relaparotomy was performed 14 days after the first surgery. Effect of pirfenidone on adhesion formation was assessed on light microscopy by scoring vascular proliferation, inflammation, fibrosis, and collagen formation in the scarred tissue. Effect of pirfenidone on inflammation was assessed by measurement of transforming growth factor-β and interleukin-17 levels in scarred tissue. Results: The degree of vascular proliferation (1.32 ± 0.39 versus 2.34 ± 0.46, p < 0.001), inflammation (1.60 ± 0.70 versus 2.60 ± 0.52, p < 0.01), and fibrosis (1.50 ± 0.53 versus 2.40 ± 0.52, p < 0.01) were less prominent in group 2 compared to group 1, respectively. Only vascular proliferation was found to be less prominent in group 3 compared to group 1 (1.60 ± 0.42 versus 2.34 ± 0.46, p < 0.01). Intraperitoneal and oral administration of pirfenidone reduced tissue levels of inflammatory markers (TGF-β and IL-17) in parietal and visceral peritoneum compared to control group. Intraperitoneal administration of pirfenidone compared to oral administration was more effective in reducing tissue levels of inflammatory markers. Conclusion: Pirfenidone is an effective agent on the prevention of postoperative vascular proliferation, inflammation and fibrosis in scarred tissue particularly with intraperitoneal administration.

Matrix changes due to the toxic effects of metronidazole in intestinal tissue of fish (Onchorhynchus mykiss)

Metranidazole (MTZ) is an antibiotic used for parasitic infections in a number of species. Accumulation of this drug in the environment and its interaction with fish of economic value makes this drug particularly important. In the present study, we examined the histopathological effects of MTZ on the intestinal tissue of Oncorhynchus mykiss. The fish in aquarium were exposed to MTZ at doses of 5, 10, 20 mg/L for 2, 4 and 8 days. At the end of the experiments, macroscopic pathology or death were not observed at these doses. Histochemical staining with Haematoxylene-Eosin, Periodic Acid Schiff and Gomori Trichrome showed, depending on increased dose and prolonged duration, areas of necrosis, edema, inflammation, small tears at the tips of the villi and excretion with heterogenic distribution of the Goblet cells. Moreover, changes in the connective tissue of the intestines due to toxicity of MTZ and decreases in immunostaining of matrix proteins such as laminin and collagen IV, especially in the epithelium were observed. Findings of the present study would be useful to demonstrate the adverse effects of MTZ use, emphasizing the importance of the effect on fish which could be very important public health.

Anatomy of stem cells

Human embryonic stem cells are important for the understanding of biologic mechanisms and their potential for treatment, and for toxicology studies. Mesenchymal stem cells can produce a good environment with chemical factors and signals to serve as anti-apoptotic, immune modulator and angiogenic, and can support regeneration in damaged tissues and induce faster and better wound healing. Stem cells have recently been shown in cancer tissue; these play a major role in the progression of cancer and the principal obstacle in treatment due to their resistance. Stem cells may participate in tissue homeostasis and regeneration which shows their capacity for cell therapies which makes them an amazing source for the clinical translation to treatment of diseases. Therefore, better understanding of the behavior of these cells and the mechanisms they use are important. Keywords: cancer; embryonic; hematopoietic; mesenchymal; pluripotent; stem cell