A Novel Ensemble Framework for Multi-Classification of Brain Tumors Using Magnetic Resonance Imaging.

Brain tumors can have fatal consequences, affecting many body functions. For this reason, it is essential to detect brain tumor types accurately and at an early stage to start the appropriate treatment process. Although convolutional neural networks (CNNs) are widely used in disease detection from medical images, they face the problem of overfitting in the training phase on limited labeled and insufficiently diverse datasets. The existing studies use transfer learning and ensemble models to overcome these problems. When the existing studies are examined, it is evident that there is a lack of models and weight ratios that will be used with the ensemble technique. With the framework proposed in this study, several CNN models with different architectures are trained with transfer learning and fine-tuning on three brain tumor datasets. A particle swarm optimization-based algorithm determined the optimum weights for combining the five most successful CNN models with the ensemble technique. The results across three datasets are as follows: Dataset 1, 99.35% accuracy and 99.20 F1-score; Dataset 2, 98.77% accuracy and 98.92 F1-score; and Dataset 3, 99.92% accuracy and 99.92 F1-score. We achieved successful performances on three brain tumor datasets, showing that the proposed framework is reliable in classification. As a result, the proposed framework outperforms existing studies, offering clinicians enhanced decision-making support through its high-accuracy classification performance.

Comparison of the effects of fluoxetine and venlafaxine on bone healing in a rat calvarial defect model.

OBJECTIVE: The purpose of this study was to compare the effects of the selective serotonin reuptake inhibitor (SSRI) fluoxetine and the serotonin-norepinephrine reuptake inhibitor (SNRI) venlafaxine on bone defect healing. MATERIALS AND METHODS: Wistar rats were randomly divided into three groups of eight animals each. The first received 0.1 ml/kg sterile saline solution, the second 5 mg/kg fluoxetine, and the third 5 mg/kg venlafaxine, daily by gastric gavage over 7 weeks. At week 3 of drug therapy, 5-mm diameter calvarial defects were created in the parietal bone of all of the animals. All rats were euthanized four weeks after surgery, micro-CT analysis and histomorphometric analysis were carried out to evaluate the following parameters: Bone volume fraction (BV/TV), bone surface (BS), bone surface density (BS/BV; bone surface/bone volume, 1/mm), trabecular number (Tb. N), trabecular thickness (Tb. Th), areas of new bone structure (positive areas), areas of mature bone structure (negative areas). RESULTS: Micro-CT analysis showed the presence of similar levels of bone formation within the defect site in all three groups (p>0.05). Histomorphometric analysis revealed the presence of bone-forming cells at the defect periphery, with less activity indicating bone formation at the center. No statistically significant difference was observed between the groups (p>0.05). CONCLUSION: Based on the findings of this study, it can be said that the use of both antidepressants hasn't any effect on bone defect healing.

The potential clinical relevance of anatomical structures and variations of the maxillary sinus for planned sinus floor elevation procedures: A retrospective cone beam computed tomography study.

BACKGROUND: Complications arising from sinus floor elevation (SFE) with lateral approach surgery can be avoided by means of maxillary sinus examination in the preoperative period. PURPOSE: To investigate anatomical variations in the maxillary sinus by making use of cone beam computed tomography (CBCT) in terms of SFE with a lateral approach. MATERIALS AND METHODS: Two hundred twenty eight maxillary sinuses in 114 patients were included. Parameters such as the position and diameter of the posterior superior alveolar artery (PSAA) canal, the frequency and localization of the septa or accessory maxillary ostium (AMO), and lateral wall thickness values were subjected to statistical analysis. RESULTS: Septa were observed in 35.1% of sinuses. The majority of septa were determined in the middle region (48.8%). Additionally, 71.1% of PSAA canals were intraosseous, generally exceeding 1 mm in diameter (68.9%). The shortest mean perpendicular distance between the sinus floor and the PSAA canal was determined in the first molar region (9.22 ± 5.66 mm). Similarly, the highest mean sinus lateral wall thickness was determined in the first molar region, in the area 3 mm distant from the sinus floor (2.42 mm ± 0.88 mm). AMO was detected in 40.8% of sinuses. CONCLUSION: CBCT-guided treatment planning may be beneficial prior to SFE procedures in order to avoid surgical complications.

Local treatment of chronic osteomyelitis with surgical debridement and tigecycline-impregnated calcium hydroxyapatite: an experimental study.

OBJECTIVE: The aim of this study was to determine the efficacy of tigecycline-impregnated hydroxyapatite in the local treatment of chronic osteomyelitis experimentally induced in rat tibias with methicillin-resistant Staphylococcus aureus. STUDY DESIGN: Monocortical defects were established in the left tibias of 32 adult Wistar albino rats. Five rats were randomly selected and injected intramedullarly with saline solution (group 1), whereas chronic osteomyelitis was induced in other rats by intramedullary injection of S. aureus. Infected rats were then randomized and divided into 4 groups: group 2, no further treatment; group 3, debridement only; group 4, debridement followed by implantation of calcium hydroxyapatite; and group 5, debridement followed by implantation of tigecycline-impregnated calcium hydroxyapatite. On day 21 after induction, all rats in groups 2-5 showed signs of osteomyelitis. Rats in groups 1 and 2 were killed on day 21 after induction, whereas rats in groups 3, 4, and 5 underwent debridement surgery on day 21 after induction and were killed 21 days after debridement surgery. Tibias were analyzed histopathologically and cultured for S. aureus. RESULTS: Compared with group 2, histopathologic disease severity scores in groups 3, 4, and 5 were 37%, 44%, and 83% lower, respectively. Nontreated infected rats had the highest bacteria count (mean 5 × 10(5) colony-forming units/g bone), and bacterial count was 26%, 29%, and 79% lower in groups 3, 4, and 5, respectively, compared with group 2. CONCLUSIONS: Tigecycline-impregnated hydroxyapatite can have a potential in the treatment of chronic osteomyelitis of methicillin-resistant S. aureus origin, which may be considered as a therapeutic alternative by surgeons dealing with osteomyelitis.

The use of 808-nm light therapy to treat experimental chronic osteomyelitis induced in rats by methicillin-resistant Staphylococcus aureus.

BACKGROUND DATA: In vivo and in vitro studies have reported that laser energy in differing wavelengths and irradiation regimes has a potential bactericidal effect on Staphylococcus aureus. OBJECTIVE: The purpose of this study was to investigate whether a light wavelength of 808 nm in varying doses has an effect on chronic osteomyelitis induced experimentally in the rat tibia. METHODS: Intramedullary cavities were surgically created in the left tibias of 39 adult Wistar albino rats. Five randomly selected subjects were injected with a sterile saline solution, and methicillin-resistant S. aureus (MRSA) was used to induce osteomyelitis in the remaining rats. After 3 weeks, rats with evidence of osteomyelitis were treated with debridement alone (n = 7), with debridement plus laser irradiation to induce photoeradication (n = 21), or were not treated at all [negative control, (n = 6)]. Active irradiation was performed using an 808 nm, 100 mW continuous-wave diode laser with a beam spot size of 0.7854 cm(2) (irradiance = 127.3 mW/cm(2)). Laser treatment commenced immediately after debridement surgery and was applied daily for 5 consecutive days. Irradiation lasted 60 secs (6 J at 7.64 J/cm(2): n = 7), 120 secs (12 J at 15.29 J/cm(2): n = 7), or 180 secs (18 J at 22.93 J/cm(2): n = 7). Rats in the sham and negative control groups were killed 21 days post-induction surgery, and those in the treatment groups were killed after 42 days. Following killing, tibias were removed and analyzed histopathologically, radiographically, and microbiologically. RESULTS: Histopathological analysis showed that infection levels had decreased by 37%, 67%, 81%, and 93% in the groups treated by debridement or by debridement plus 7.64, 15.29, and 22.93 J/cm(2) light therapy, respectively, compared to the negative control group. Osteomyelitis-induced rats had the highest bacteria count (5 × 10(5)). Bacterial counts fell to 1.6 × 10(4), 4.3 × 10(2), 5.5 × 10(1), and 3.3 × 10(0) in groups treated by debridement or by debridement plus 7.64, 15.29, and 22.93 J/cm(2) light therapy, respectively, compared to the negative control group. CONCLUSIONS: Within the limitations of this study, laser phototherapy with the appropriate irradiation parameters appears to be a promising adjunct and/or alternative technique to pharmacological agents in the treatment of osteomyelitis. The 808 nm 100 mW (127.3 mW/cm(2)) laser device used in this study achieved a maximum effect with an irradiation time of 180 secs, delivering 18 J at an energy density of 22.93 J/cm(2).

Effect of tadalafil on renal resistivity and pulsatility index in partial ureteral obstruction.

INTRODUCTION: To investigate the effect of tadalafil on Resistivity Index (RI) and Pulsatility Index (PI) in partial unilateral ureteral obstruction (PUUO). METHODS: Twelve New Zealand rabbits were assigned into two groups. Baseline renal Doppler ultrasonography (USG) was performed in all rabbits. The rabbits in group 1 received tadalafil for a month (10 mg/72 h) and group 2 was defined as sham. After 1 month, in both groups left PUUO was created. Renal Doppler USG was performed to measure RI and PI parameters of both kidneys on the 4th hour and 1st and 3rd days postoperatively. RESULTS: Baseline renal Doppler USG revealed that there was no difference between two kidneys in both groups. The differences in mean RI and PI values of the kidneys between the sham and tadalafil groups were not statistically significant. Compared with the preoperative values, postoperative RI and PI values for the left kidneys were significantly increased in the period from 4 h to 3 days postoperatively in the sham group (p < 0.05). However, mean RI and PI values were not increased in the tadalafil group when compared with the sham group and this difference between the two groups was significant (p < 0.05). CONCLUSIONS: Tadalafil has a lowering affect on RI and PI in experimentally created PUUO.

Evaluation of free radical formation associated with diagnostic ultrasound.

Our objective was to evaluate kidney antioxidant status in rats subjected to an ultrasound examination. Thirty rats were divided into five groups for injection of saline (S) or anesthetic (A), and application of ultrasound using different modes, B mode, pulsed wave Doppler, and continuous wave Doppler, under anesthesia. Ultrasound was performed on days 1, 3, and 5 relative to the initiation of the experiment. Rats were then scarified on day 6. The kidney tissue thiobarbituric acid reactive substance (TBARS) level and superoxide dismutase (SOD) activity were measured. Both TBARS level and SOD activity increased, 21% and 38%, respectively, due to anesthesia (P < 0.04 for both). SOD activity increased further by a factor of 1.2 in response to ultrasound examination (P < 0.05), whereas TBARS level was not affected by Doppler and continuous wave Doppler compared to anesthesia. Increases in the level of TBARS (P < 0.03) and SOD activity (P < 0.01) were greatest when B-mode ultrasound was employed. These substances did not increase further when continuous wave Doppler was employed. The peak-negative acoustic pressure (9.16 vs. 9.74 MPa) and frequency (3.57 vs. 6.95 MHz) for B mode and pulsed wave Doppler were greater than those for continuous wave Doppler (0.22 MPa and 1.96 MHz). The estimated mechanical indexes were 4.87, 3.70, and 0.15 for B mode, pulsed wave Doppler, and continuous wave Doppler, respectively. In conclusion, anesthesia may cause tissue damage as reflected by elevated lipid peroxidation and free radical formation and ultrasound examination may amplify tissue damage through mechanical effects caused by ultrasound absorption.