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Cardiac hypertrophy (CH) is an adaptational enlargement of the myocardium, in exposure to altered stress conditions or in case of injury which can lead to heart failure and death. MicroRNAs (miRNAs) are noncoding RNAs that play a significant role in modulating gene expression. Here, we aimed to identify new miRNAs effective in an experimental CH model and to find an epigenetic biomarker that could demonstrate therapeutic targets responsible for the pathology of heart tissue and serum. In this study, Sprague-Dawley male rats were divided into the training group (TG, n =9) and the control group (CG, n =6). Systolic and diastolic dimensions of the left ventricle and myocardial wall thickness were measured by echocardiography to assess CH. After the exercise program of the rats, miRNA expression measurements and histological analyses were performed. The 25,000 genes in the rat genome were searched using microarray analysis. A total of 128 miRNAs were selected according to the fold change rates, and nine miRNAs were validated for expression analysis. The terminal deoxynucleotidyl transferase dUTP nick (TUNEL) method was used to detect apoptotic cells. Cell proliferation was evaluated by the proliferative cell nuclear antigen (PCNA) method. Necrosis, bleeding, and intercellular edema were detected in TG. The mean histopathological score was higher in TG (p=0.03). There were rarely positive cells for apoptosis of both groups in cardiomyocytes. In the receiver characteristic curve analysis (ROC), the heart tissue rno-miR-290 had an area under the curve (AUC) of 0.920 with 100% sensitivity and 89.90% specificity (p=0.045), rno-miR-194-5p had AUC of 0.940 with 83.33% sensitivity and 100% specificity (p=0.003), and the serum rno-miR-132-3p AUC was 0.880 with 66.67% sensitivity and 100% specificity ( p =0.004) in TG. miR-194-5p was used as a therapeutic target for remodeling the cardiac process. While miR-290 contributes to CH as a negative regulator, miR-132 in serum is effective in the pathological and physiological cardiac remodeling process and is a candidate biomarker.

In this study, a hybrid processing method using saline and cryogen cooler is proposed to keep the temperature below the threshold level during bone drilling. Drilling experiments were performed dry, saline, cryogen and, hybrid (saline + cryogen). At the end of the experiment, tool wear, the effect of the methods on the temperature, and the pathological evaluation of the thermal damage were investigated. The advantageous methods for bone drilling were proposed as a hybrid, saline, cryogenic and dry machining, respectively. In addition, it was observed that when cryogen was applied directly to the cutting area, it caused damage to the cell wall structure by the formation of ice crystals in the bone matrix. For this reason, it was recommended to be applied to the body of the cutting tool and it was found that cryogen flow rate has a significant effect on tool wear., (Copyright © 2021. Published by Elsevier Ltd.)

Background: The aims of our study were to compare the histomorphological characteristics of carotid plaques and glycosylated hemoglobin (HbA1c), which are risk factors for ischemic stroke, in patients who underwent carotid endarterectomy for carotid artery stenosis. Moreover, we aimed to identify the structures that were histologically affected by symptomatic carotid plaques in cases with elevated HbA1c., Materials and Methods: A total of 64 patients who presented with ischemic stroke and had not previously been diagnosed with diabetes were retrospectively evaluated. All stroke risk factors were reviewed. Carotid plaques were graded separately by two different pathologists through microscopic assessment of the following parameters: plaque rupture, lipid core, fibrous cup thickness, inflammation, intraplaque hemorrhage, thrombus, calcification, necrotic core, and neovascularization. An HbA1c value <6.3% was accepted as normal or indicative of prediabetes (group 1), whereas patients with values ranging between 6.3-7.4%, 7.5-8.4%, and >8.4% were categorized into the effectively controlled (group 2), less effectively controlled (group 3), and uncontrolled (group 4) groups, respectively., Results: The mean age of the patients was 73.0 ± 4.5 years in group 1, 69.7 ± 2.3 years in group 2, 66.0 ± 8.5 years in group 3, and 62.7 ± 7.1 years in group 4. A negative correlation was present between age and HbA1c. Smoking, hypertension, low-density lipoprotein cholesterol levels, and triglyceride levels were not significantly different among the four groups. According to the HbA1c classifications, the fibrous cup thickness was 2.64 ± 0.3 mm in group 1, 1.85 ± 0.4 mm in group 2, 1.68 ± 0.5 mm in group 3, and 1.45 ± 0.6 mm in group 4. The fibrous cup became thinner as the HbA1c value increased. Other parameters of unstable carotid plaques did not differ among the HbA1c groups., Conclusions: Increased HbA1c values seem to contribute to plaque instability through the formation of a thin fibrous cup. Thus, of the carotid artery plaque parameters including fibrous cup thickness, plaque rupture, lipid core, inflammation, intraplaque hemorrhage, thrombus, calcification, necrotic core, and neovascularization, fibrous cup thickness is the only histomorphological feature that affected by HbA1c., Competing Interests: None