Zafer Kucukodaci

Scintigraphic Evaluation of Osteoblastic Activity in Extraction Sockets Treated With Platelet-Rich Fibrin

PURPOSE To evaluate the effect of platelet-rich fibrin (PRF) on the early bone healing process with bone scintigraphy based on technetium-99m methylene diphosphonate uptake in third molar extraction sockets. PATIENTS AND METHODS Fourteen patients with bilaterally soft tissue impacted third mandibular molars were included in the study. The right and left impacted third molars were surgically extracted in the same session. PRF was randomly administered into one of the extraction sockets, whereas the contralateral sockets were left without treatment. Four weeks after surgery, scintigrams were obtained to evaluate scintigraphic differences between PRF-treated and non-PRF-treated sockets. After completion of the clinical study, PRF samples were evaluated by light and scanning electron microscopy. RESULTS The average increase in technetium-99m methylene diphosphonate uptake as an indication of enhanced bone healing did not differ significantly between PRF-treated and non-PRF-treated sockets 4 weeks postoperatively (P > .05). Abundant fibrin and inflammatory cells were observed by light microscopic examination of PRF samples. Scanning electron microscopic analysis of PRF revealed the existence of platelet aggregates in a fibrin network and crystalline particles on the outer surface of PRF. CONCLUSIONS PRF might not lead to enhanced bone healing in soft tissue impacted mandibular third molar extraction sockets 4 weeks after surgery. PRF exhibits the potential characteristics of an autologous fibrin matrix. However, whether the presence of crystal-like particles on the outer surface of PRF alters bone healing should be investigated further.

CYP1A1 (Ile462Val), CYP1B1 (Ala119Ser and Val432Leu), GSTM1 (null), and GSTT1 (null) polymorphisms and bladder cancer risk in a Turkish population.

We aimed to investigate bladder cancer risk with reference to polymorphic variants of cytochrome p450 (CYP) 1A1, CYP1B1, glutathione S-transferase (GST) M1, and GSTT1 genes in a case control study. Polymorphisms were examined in 114 bladder cancer patients and 114 age and sex-matched cancer-free subjects. Genotypes were determined using allele specific PCR for CYP1A1 and CYP1B1 genes, and by multiplex PCR and melting curve analysis for GSTM1 and GSTT1 genes. Our results revealed a statistically significant increased bladder cancer risk for GSTT1 null genotype carriers with an odds ratio of 3.06 (95% confidence interval=1.39-6.74, p=0.006). Differences of CYP1A1, CYP1B1 and GSTM1 genotype frequencies were not statistically significant between patients and controls. However, the specific combination of GSTM1 null, GSTT1 null, and CYP1B1 codon 119 risk allele carriers and specific combination of GSTM1 present, GSTT1 null, and CYP1B1 432 risk allele carriers exhibited increased cancer risk in the combined analysis. We did not observe any association between different genotype groups and prognostic tumor characteristics of bladder cancer. Our results indicate that inherited absence of GSTT1 gene may be associated with bladder cancer susceptibility, and specific combinations of GSTM1, GSTT1 and CYP1B1 gene polymorphisms may modify bladder cancer risk in the Turkish population, without any association being observed for CYP1A1 gene polymorphism and bladder cancer risk.

Histologic analysis of the effects of three different support materials within rat middle ear

Objective: To investigate histologic changes in the mucosa of rat middle ear after implantation of three different support materials. Study Design: A prospective, controlled animal study. Subjects and Methods: Three types of absorbable materials were implanted into the middle ear cavity of rats: (1) Gelfoam (purified gelatin) (Pharmacia & Upjohn Company, New York, NY), (2) Sepragel (viscoelastic gel composed of cross-linked polymers of hyaluronan) (GENZYME Corp, Ridgefield, NJ), and (3) Nasopore (a biodegradable/fragmentable, synthetic polyurethane foam) (Polyganics, Groningen, The Netherlands). Rats were sacrificed after 3 and 20 days to ascertain early and late histologic changes. The bulla of each rat was excised and prepared for microscopic examination. The histologic changes were evaluated by observation of the middle ear cavity and mucosa in terms of polymorphonuclear leucocytes (PMNL), macrophages, giant cells, fibroblasts and other cells, fibrosis, and remnant materials. Results: The histologic appearance of gelfoam-treated middle ears was characterized by more severe acute inflammation in the short-term and prominent fibrosis in the long-term in comparison with sepragel- and nasopore-treated groups. Nasopore appeared to be prone to remnant formation and reorganization by means of fibroblastic activity. Conclusion: Compared with gelfoam, both sepragel and nasopore caused less histologic alterations.

The effects of tissue fixation alternatives on DNA content: a study on normal colon tissue.

The aim of this study is to investigate the effects of different fixatives on DNA, and to evaluate the fixation options for molecular studies including polymerase chain reaction (PCR) and fluorescence in-situ hybridization (FISH). Three normal-looking colonic segments from surgical resections were used for tissue sampling. The full thickness of the colonic tissues (3 mm diameter) was sampled. Tissues were fixed in 70% ethanol, 10% neutral-buffered formalin, Hollande, B5, Bouin, and Zenker solutions for 1, 2, 5, 12, 24, and 48 hours, and processed and embedded in paraffin in a standard protocol. Quantitative measurements of the extracted DNA were carried out. DNA quality was tested by PCR for the human β globin gene. Tissue sections were also tested for the availability of FISH, by using a Her-2/neu protocol. All fixation alternatives were found to be reasonable sources of DNA for molecular studies, and they enabled the successful PCR amplification of a housekeeping gene. DNA yields were predominantly over 1000 bp in 70% ethanol and 24-hour 10% neutral-buffered formalin fixations. As for B5 and Hollande, the DNA molecules obtained were almost all smaller than 100 bp. All tissues fixed in formalin, ethanol, and Hollande were found suitable for Her-2/neu visualization after standard FISH applications, but tissues fixed in Zenker, B5, and Bouin were not found suitable.

miR-205 and miR-200c: Predictive Micro RNAs for Lymph Node Metastasis in Triple Negative Breast Cancer

Purpose We examined expression profiles of 16 micro RNAs (miRNAs) in triple negative breast cancers to identify their potential as biomarkers for lymph node metastasis. Methods The expression profiles of miR-9, miR-21, miR-30a, miR-30d, miR-31, miR-34a, miR-34c, miR-100, miR-122, miR-125b, miR-146a, miR-146b, miR-155, miR-181a, miR-200c, and miR-205 were examined by using real-time quantitative reverse transcription polymerase chain reaction in tumor samples and corresponding benign breast tissues. Their associations with histopathological features and prognostic parameters were assessed. Results When compared with the expression in benign breast tissues, seven of the miRNAs (miR-31, miR-205, miR-34a, miR-146a, miR-125b, miR-34c, and miR-181a) were downregulated more than 1.5-fold in tumor tissues, whereas, only miR-21 was found to be upregulated more than 1.5-fold in tumor tissues. Although miR-200c levels were decreased only 1.12-fold in tumor tissues, the reduced expressions of miR-200c and miR-205 were significantly associated with lymph node metastasis (p=0.021 and p=0.016, respectively). Conclusion Our results demonstrate that miR-205 and miR-200c expression levels may be useful in predicting lymph node metastasis in triple negative breast cancer patients.

Combined hyperbaric oxygen and hypothermia treatment on oxidative stress parameters after spinal cord injury: an experimental study.

BACKGROUND AND AIMS We undertook this study to investigate the possible beneficial effects of combined hypothermia and hyperbaric oxygen (HBO) treatment in comparison with methylprednisolone in experimental spinal cord injury (SCI). METHODS Forty eight male Wistar albino rats (200-250 g) were randomized into six groups; A (normothermic control group; only laminectomy), B (normothermic trauma group; laminectomy + spinal trauma), C (normothermic methylprednisolone group; laminectomy + spinal trauma + methylprednisolone treated), D (hypothermia group; laminectomy + spinal trauma + hypothermia treated); E (HBO group; laminectomy + spinal trauma + HBO therapy), F (hypothermia and HBO group; laminectomy + spinal trauma + hypothermia and HBO treated) each containing eight rats. Neurological assessments were performed 24 h after trauma and spinal cord tissue samples had been harvested for both biochemical and histopathological evaluation. RESULTS After SCI, tissue malondialdehyde (MDA) level of the control group was measured increased, and superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and catalase (CAT) enzyme activities were measured decreased. In group F, it was also shown that MDA level elevation had been prevented, and group F has increased the antioxidant enzyme activities than the other experimental groups C, D, E (p <0.05). CONCLUSIONS We concluded that the use of combined hypothermia and HBO treatment might have potential benefits in spinal cord tissue on secondary damage.

In vivo evaluation of titanium-prepared platelet-rich fibrin (T-PRF): a new platelet concentrate

We have developed a new, titanium-prepared, platelet-rich fibrin (T-PRF) together with the protocol for forming it, which is based on the hypothesis that titanium tubes may be more effective at activating platelets than the glass tubes used by Chouckroun in his platelet-rich fibrin (PRF) method. The aim of this study was to find a suitable animal model in which to evaluate the method and to investigate the efficacy of T-PRF for wound healing. Blood samples from 6 rabbits were used to confirm the protocol for formation of T-PRF. We evaluated T-PRF or T-PRF-like clots morphologically using scanning electron microscopy (EM). Blood samples from 5 rabbits were used to develop an experiment in which to evaluate the effects of T-PRF on wound healing. The mucoperiosteal flaps were filled with autologous T-PRF membranes from the vestibule in the anterior mandibular regions. Samples collected from the surgical sites were stained with haematoxylin and eosin. We found a mature fibrin network in T-PRF clots that had been centrifuged for 15 min at 3500 rpm and, 15 days after placement of the membrane, we found newly-forming connective tissue and islets of bony tissue in the T-PRF membrane. These results show that T-PRF could induce the formation of new bone with new connective tissue in a rabbit model of wound healing within 30 days of treatment.

The Comparison of the Effects of Different Doses of Levobupivacaine Infiltration on Wound Healing

Introduction-Aim: The easiest method in postoperative analgesia is the infiltration of the wound with local anesthetic drugs. Although many local anesthetic drugs have been used for this type of infiltration, studies on levobupivacaine are rare. The aim of this study was to investigate the effects of different concentrations of levobupivacaine infiltration on wound healing. Method: Forty female Wistar-Albino rats (280–300 g) were included in the study, which were randomly separated into four groups. Rats were infiltrated with 1.25 mg/mL levobupivacaine in group L1.25 (n = 10), with 2.50 mg/mL levobupivacaine in group L2.5 (n = 10), with 3.75 mg/mL levobupivacaine in group L3.75 (n = 10), and with normal saline in control group (n = 10). Breaking-strength measurements, levels of hydroxyproline, and fibrotic index were evaluated in the tissue samples taken from the rats. Results: When the breaking-strength measurements were evaluated, we have found a significant difference between the control and the study groups (p < 0.05). In the intergroup comparison the difference between groups L1.25 and L3.75 was statistically significant (p < 0.05). In all of the levobupivacaine groups the levels of hydroxyproline were higher compared to the control group. Also significant differences were observed between groups L1.25 and L2.5 and groups L1.25 and L3.75 (p < 0.05). The levels of tissue fibrotic index were higher in all of the levobupivacaine groups compared to the control group (p < 0.05) and also a difference was observed between groups L1.25 and L3.75 in terms of tissue fibrotic index (p < 0.05). Conclusion: We have concluded that levobupivacaine used in clinical doses have a significant effect on the fastening of wound healing and this effect increases with an increase in the concentration of the levobupivacaine. We believe that levobupivacaine will be more widely preferred in the near future in the postoperative analgesia.

Scintigraphic, Histologic, and Histomorphometric Analyses of Bovine Bone Mineral and Autogenous Bone Mixture in Sinus Floor Augmentation: A Randomized Controlled Trial—Results After 4 Months of Healing

PURPOSE To test our null hypothesis stating that the mixture of autogenous cortical bone scrapings and bovine bone mineral (BBM) in a ratio of 1:4, compared with BBM alone, would have no significant effect on new bone formation 4 months after maxillary sinus floor augmentation. PATIENTS AND METHODS Twenty-four patients presenting with alveolar bone height of less than 5 mm in the narrowest zone between the sinus floor and alveolar crest were randomly assigned to 2 treatment groups in this randomized controlled trial. We augmented 12 maxillary sinuses with a mixture of BBM and cortical autogenous bone graft, which was collected from the lateral wall of the maxillary sinus by a bone scraper, and 12 maxillary sinuses with BBM alone. Four months postoperatively, new bone formation in the augmented sinus sites was evaluated through bone scintigraphy, as well as histologic and histomorphometric analyses of the biopsy specimens obtained during implant placement. Data were statistically analyzed by independent-samples t test. RESULTS Scintigraphically detectable new bone formation did not differ significantly between the groups (P > .05). Histologic findings showed that the new bone bridged between BBM particles and BBM underwent resorption by osteoclasts with or without the addition of autogenous bone graft. According to histomorphometric findings, the difference between the percentages of newly formed bone in the sinuses augmented with graft mixture (25.73%) and BBM alone (24.19%) was statistically nonsignificant (P > .05). CONCLUSIONS The addition of autogenous cortical bone scrapings to BBM in a ratio of 1:4, compared with BBM alone, does not markedly increase new bone formation 4 months after maxillary sinus lifting.

Clinical significance of miR-140-5p and miR-193b expression in patients with breast cancer and relationship to IGFBP5

The functional role of IGFBP5 in breast cancer is complicated. Experimental and bioinformatics studies have shown that IGFBP5 is targeted by miR-140-5p and miR-193b, although this has not yet been proven in clinical samples. The aim of this study was to evaluate the expression of miR-140-5p and miR-193b in breast cancer and adjacent normal tissue and assess its correlation with IGFBP5 and the clinicopathological characteristics of the tumors. IGFBP5 protein expression was analyzed immunohistochemically and IGFBP5, miR-140 and miR-193b mRNA expression levels were analyzed with real-time RT-PCR. Tumor tissue had higher miR-140-5p expression than adjacent normal tissue (p = 0.015). Samples with no immunohistochemical staining for IGFBP5 showed increased miR-140-5p expression (p = 0.009). miR-140-5p expression was elevated in invasive ductal carcinomas (p = 0.002), whereas basal-like tumors had decreased expression of miR-140-5p compared to other tumors (p = 0.008). Lymph node-positive samples showed an approximately 13-fold increase in miR-140-5p expression compared to lymph node-negative tissue (p = 0.049). These findings suggest that miR-140-5p, but not miR-193b, could be an important determinant of IGFBP5 expression and clinical phenotype in breast cancer patients. Further studies are needed to clarify the expressional regulation of IGFBP5 by miR-140-5p.