Aslıhan Alhan

Effectiveness of the biophysical barriers on the peridural fibrosis of a postlaminectomy rat model: An experimental research

PURPOSE Long term results after surgical treatment of disc herniation have shown that epidural and/or peridural fibrosis formed during the healing process after surgical intervention. We conducted this experimental study to evaluation of the effectiveness of the bioresorbable barriers (ADCON-L and Seprafilm(®) Adhesion Barrier) on formation of the peridural fibrosis in rat model performed laminectomy. METHODS Thirty-two male Wistar albino rats 250-350g body weight were distributed into three groups (CONTROL, AL group received ADCON-L; SAB group received Seprafilm(®) Adhesion Barrier). A dorsal laminectomy at L3, L4, L5 was performed, and then except those of the CONTROL group, the experimental material was left on the dura mater. Six weeks later spinal column of all rats was totally removed between the T10 and L5 levels, and peridural fibrosis, and dural adhesions were evaluated histologically and graded. The results were compared statistically by using the chi-square (χ(2)) test. Also three random regions were examined, and the fibroblast cells were counted. The fibroblast count results were statistically analysed by using the One-Way ANOVA test. RESULTS The variation of histopathological grades was statistically significant regarding the comparison of the all groups obtained from the χ(2) test (χ(2)=16.40; p=0.003). However, the variation in the mean values of the fibroblast count result was not statistically significant obtained from the One-Way ANOVA test (F=2.114; p>0.05). CONCLUSION Our study results suggest that Seprafilm(®) Adhesion Barrier and ADCON-L can be effective in reducing the prevalence of the postoperative peridural adhesions in rat laminectomy model. On the other hand, the fibroblast densities of the experimental groups were not different between groups. So, we could say that these materials can act as a foreign body in long term period in rat.

Is mean platelet volume associated with the angiographic severity of coronary artery disease

BACKGROUND Platelet activation and aggregation play key roles both in the pathogenesis of atherosclerosis and in the developmentof acute thrombotic events. Platelet volume is a marker of platelet activation and function, and is measured usingmean platelet volume (MPV). AIM To determine the relationship between MPV and angiographic Gensini and SYNTAX scores, which give information about the severity and complexity of coronary artery disease (CAD). METHODS This study included 435 consecutive patients undergoing elective coronary angiography. The complete blood countand biochemical examination of blood were obtained after 12 h of fasting. The independent association between MPV andthe severity of CAD was statistically evaluated using PASW Statistics 18 for Windows. RESULTS Mean age of the study population was 58.4 ± 9.3 years, of whom 196 were female (45.1%) and 239 male (54.9%). Of the patients, 63.2% had CAD, 31.7% had diabetes mellitus, 61.8% had hypertension, 56.6% had hyperlipidaemia, and 38.6% were smokers. Mean Gensini score was 20.7 ± 31.1. According to Gensini scores, 160 of the patients (36.8%) hadnormal coronary arteries (Gensini score: 0), 134 of the patients (30.8%) had minimal CAD (Gensini score: 1-19), and 141 ofthem (32.4%) had severe CAD (Gensini score ≥ 20). Mean MPV values were 8.4 ± 1.0 fL in the group that had no CAD,8.7 ± 1.0 fL in the group with minimal CAD, and 9.3 ± 1.5 fL in the group with severe CAD. According to Spearman correlationanalysis, the positive relationship found between MPV and Gensini score was statistically significant (p < 0.001,r = 0.290). Likewise, SYNTAX score was also associated with MPV (p < 0.001, r = 0.504). CONCLUSIONS We determined a positive correlation between MPV and Gensini and SYNTAX scores. Therefore, this simple haematology test can be used in determining cardiovascular disease burden besides other risk factors during routine clinical practice. For further information about this topic, large-scale studies are needed.

Neutrophil to lymphocyte ratio is associated with more extensive, severe and complex coronary artery disease and impaired myocardial perfusion

OBJECTIVES We investigated the relation between neutrophil to lymphocyte ratio (N/L) and the extent, severity, and complexity of coronary artery disease (CAD) and myocardial perfusion. STUDY DESIGN One hundred and fifty-one patients who underwent coronary angiography with stable angina pectoris (SAP) (n=93) or acute coronary syndrome (ACS) (n=58) were included in the study. Blood samples were drawn before coronary angiography. Gensini and SYNTAX scores and myocardial blush grade (MBG) were assessed. RESULTS Neutrophil counts were 4.4±1.4 and 5.0±1.6 in the SAP and ACS groups (p=0.018), whereas lymphocyte counts were 2.2±0.7 and 2.1±0.7, respectively (p=0.104). N/L was 2.2±1.2 in the SAP and 2.6±1.0 in the ACS (p=0.002) groups. In patients with SAP, N/L was significantly correlated with Gensini and SYNTAX scores (Gensini score r=0.32, p=0.002; SYNTAX score r=0.36, p=0.000), but there was no significant correlation between N/L and MBG. In the ACS group, N/L had a more powerful association with both Gensini and SYNTAX scores (Gensini r=0.42, p=0.001; SYNTAX r=0.51, p=0.000). N/L was negatively correlated with MBG in ACS patients (r= -0.48, p=0.000). Significant correlations persisted both in the SAP and ACS groups after correcting for age, diabetes, hyperlipidemia, and statin use; however, the associations were weaker. Cut-off N/L to predict moderate to severe CAD according to SYNTAX score was 2.26, with 72% sensitivity and 71% specificity (area under the curve [AUC]: 0.772, 95% confidence interval [CI] 0.679-0.865, p<0.001). CONCLUSION N/L is associated with severe, extensive and complex CAD and may be used to predict moderate to severe involvement in patients with CAD.

Evaluation of the neurotoxicity of DMSO infused into the carotid artery of rat

INTRODUCTION Despite the explanations put forth in many studies regarding histopathological evidence of the inflammatory stage related with the infusion of dimethyl sulfoxide (DMSO) in the vessel wall and its lumen, there has been no research to evaluate its neural toxicity when it is infused via the intracarotid route. This study was designed to evaluate the possible neurotoxic effects of DMSO on the closer and distant brain tissue and carotid artery when it was slowly infused into the internal carotid arteries of the rats. METHODS The right common carotid artery bifurcation was exposed through a midline neck incision, and then except those of the control group animals (n=5), the experimental material (normal saline, n=5 or anhydrous DMSO, n=10) was infused into the internal carotid artery of the Wistar albino rats. After the experimental materials were administered intra-arterially, brain tissues were harvested for histopathological and biochemical studies at 72 h for investigation of the acute stage changes and on 10th day for investigation of the chronic stage changes. Internal carotid arteries of both sides were also removed for histopathological evaluation. During sacrification of the rats, whole body blood of them are collected for biochemical evaluation. RESULTS There was no statistically significant difference between the groups regarding comparison of the mean values of the hippocampal neuronal cell counts and the carotid artery diameters in both acute and chronic stages. Also, mean values of the lipid peroxidation levels of harvested brain tissues and serums of the collected bloods were similar in control, saline and DMSO groups. CONCLUSION This experimental study suggested that DMSO has no toxic effect on the neural and arterial tissues of rats when it is slowly infused into the carotid artery.

The relationship between serum uric acid levels and angiographic severity of coronary heart disease

BACKGROUND Many studies have shown that the serum uric acid (SUA) level is associated with atherosclerosis. AIM To determine the relationship between the SUA level and the presence and severity of coronary heart disease (CHD). METHODS A total of 705 patients who underwent coronary angiography were included in this study. All patients were assessed for the presence of cardiovascular risk factors and ongoing medications. SUA levels were measured in all patients before the procedure after 12 h of fasting. The severity of CHD was assessed by the SYNTAX score. The independent association between the SUA and the severity of CHD was statistically evaluated using IBM SPSS Statistics 21 for Windows. RESULTS The mean age of the study population was 60.2 ± 11.0 years. 252 were female (35.7%) and 453 were male (64.3%). Of the patients, 59.0% had significant CHD, 34.6% had diabetes mellitus, 67.7% had hypertension, 55.3% had hyperlipidaemia, and 45.4% were current smokers. The mean SYNTAX score was 10.6 ± 12.9. According to the SYNTAX score, 289 of the patients (41%) had normal coronary arteries and non-significant CHD (controls, SYNTAX score: 0), 236 of the patients (33.5%) had mild CHD (SYNTAX score: 1-22), 97 (13.8%) had moderate CHD (SYNTAX score: 23-32), and 83 (11.8%) had severe CHD (SYNTAX score: ≥ 33). The mean SUA values were 5.3 ± 1.5 mg/dL in the control group, 5.6 ± 1.4 mg/dL in the mild CHD group, 6.2 ± 1.6 mg/dL in the moderate CHD group, and 6.5 ± 1.7 mg/dL in the severe CHD group. According to Spearmans rho analysis, a positive correlation between the SUA levels and the SYNTAX score was determined to be statistically significant (p < 0.001, r = 0.239; p = 0.002, r = 0.148 in men; p = 0.001, r = 0.204 in women). CONCLUSIONS In this study, we found a positive correlation between the SUA level and the SYNTAX score. Therefore, this routine biochemical test can be used for the evaluation of the severity of CHD besides other risk factors in clinical practice. However, larger scale randomised studies are needed to show the effects of SUA on the severity of CHD.

Epicardial adipose tissue thickness is associated with myocardial infarction and impaired coronary perfusion.

Objective: Epicardial adipose tissue (EAT) is associated with the presence, severity and extent of atherosclerotic coronary artery disease (CAD) in addition to subclinical atherosclerosis. We investigated if EAT thickness is related to acute myocardial infarction in patients with CAD. We also searched for the association between EAT thickness and objective coronary flow and myocardial perfusion parameters such as Thrombolysis in Myocardial Infarction Frame count (TFC) and myocardial blush grade (MBG). Methods: Two-hundred consecutive patients with stable angina pectoris or acute coronary syndrome who were admitted to Ufuk University Faculty of Medicine, Dr Ridvan Ege Hospital cardiology department were included in this observational, cross-sectional study. EAT thickness was evaluated by conventional transthoracic echocardiography. Coronary angiography was performed to determine the coronary involvement and perfusion. Results: Mean EAT thicknesses were 5.4±1.9 mm, 6.3±1.8 mm, and 8.5±1.4 mm in the stable angina pectoris (SAP), unstable angina pectoris (USAP) and acute myocardial infarction groups, respectively (p<0.001). With increasing EAT thickness, TFC increases whereas mean MBG values decrease (for EAT thickness <5 mm, 5-7 mm, >7 mm; mean TFC: 21.6±2.2, 25.3±3.3 and 35.2±7.7; and MBG values: 2.98±0.14, 2.83±0.57 and 1.7±1.16, respectively; both p<0.001). Cut-off EAT value to predict AMI was identified as 7.8 mm (ROC analysis AUC: 0.876; p<0.001, 95% CI: 0.822-0.927). Sensitivity and specificity of EAT cut-off value 7.8 mm to predict AMI were 81.8% and 82.5% respectively. Conclusion: Increased EAT is associated with AMI and it may prove beneficial for choosing patients who would need more aggressive approach in terms of risk reduction using echocardiography which is a relatively cheap and readily available tool as a follow-up parameter.

Structural brain alterations of Down's syndrome in early childhood evaluation by DTI and volumetric analyses.

AbstractObjectivesTo provide an initial assessment of white matter (WM) integrity with diffusion tensor imaging (DTI) and the accompanying volumetric changes in WM and grey matter (GM) through volumetric analyses of young children with Down’s syndrome (DS).MethodsTen children with DS and eight healthy control subjects were included in the study. Tract-based spatial statistics (TBSS) were used in the DTI study for whole-brain voxelwise analysis of fractional anisotropy (FA) and mean diffusivity (MD) of WM. Volumetric analyses were performed with an automated segmentation method to obtain regional measurements of cortical volumes.ResultsChildren with DS showed significantly reduced FA in association tracts of the fronto-temporo-occipital regions as well as the corpus callosum (CC) and anterior limb of the internal capsule (p < 0.05). Volumetric reductions included total cortical GM, cerebellar GM and WM volume, basal ganglia, thalamus, brainstem and CC in DS compared with controls (p < 0.05).ConclusionThese preliminary results suggest that DTI and volumetric analyses may reflect the earliest complementary changes of the neurodevelopmental delay in children with DS and can serve as surrogate biomarkers of the specific elements of WM and GM integrity for cognitive development.Key Points• DS is the most common genetic cause of intellectual disability. • WM and GM structural alterations represent the neurological features of DS. • DTI may identify the earliest aging process changes. • DTI-volumetric analyses can serve as surrogate biomarkers of neurodevelopment in DS.

Arterial stiffness and central arterial wave reflection are associated with serum uric acid, total bilirubin, and neutrophil-to-lymphocyte ratio in patients with coronary artery disease.

Objective Total bilirubin (TB) was recently recognized as an endogenous anti-inflammatory and anti-oxidant molecule. Uric acid (UA) takes part in cardiovascular diseases by inducing oxidative stress, inflammation, and endothelial dysfunction. We assessed the relationship between serum TB levels, serum UA levels, and inflammatory status assessed by neutrophil-to-lymphocyte ratio (N/L) and arterial stiffness and arterial wave reflection in patients with a clinical diagnosis of coronary artery disease (CAD). Methods We included 145 consecutive patients admitted with stable angina pectoris (SAP) or acute coronary syndrome (ACS). Blood samples were drawn at admission for complete blood count and biochemistry. Non-invasive pulse waveform analysis for the determination of augmentation index (AIx) and carotid-femoral pulse wave velocity (PWV) measurements were performed with the commercially available SphygmoCor system. Results When patients were divided into tertiles of PWV and AIx, median N/L and median serum UA levels were the highest and mean TB levels were the lowest in the third tertile (p<0.001 for all). AIx and PWV were positively associated with serum UA and N/L and negatively associated with serum TB levels (p<0.001 for all). After adjustments for age, gender, heart rate, systolic blood pressure, and presence of diabetes, significant correlations persisted for N/L, UA, and TB in ACS patients (p<0.05). In the SAP group, TB was significantly negatively correlated with AIx and PWV, and UA was significantly positively correlated with PWV (p<0.05). Conclusion N/L ratio and serum UA and TB levels might be used to risk-stratify patients with respect to arterial stiffness in CAD patients, especially in the presence of ACS.

Central pulse pressure amplification is associated with more extensive and severe coronary artery disease.

Abstract Objectives. We investigate the association between noninvasively determined central pulse waveform characteristics and the extent and severity of coronary artery disease (CAD) in patients undergoing coronary angiography with the clinical diagnosis of CAD. Design. We included 145 consecutive patients with stable angina pectoris (SAP), unstable angina pectoris (USAP), or acute myocardial infarction (AMI) who were decided to undergo coronary angiography. Gensini and SYNTAX scores were calculated. Noninvasive PWA was performed with the SphygmoCor system. Results. Dividing the patients into tertiles according to augmentation index (AIx), more patients had significant CAD with higher Gensini and SYNTAX scores and lower myocardial blush grade (MBG) (p < 0.001 for all) in the third tertile. The AIx value to predict the presence of moderate to severe CAD as determined by SYNTAX score ≥ 23 was 24.45% (ROC analysis AUC: 0.96; sensitivity 88%, specificity: 93%, 95% CI: 0.93–0.99, p < 0.001). AIx was significantly correlated with Gensini and SYNTAX scores in SAP, USAP, and AMI patients after adjusting for age, gender, height, heart rate, hypertension, and diabetes. Conclusions. Increased AIx is associated with the presence and severity of CAD, and it may be used in selected patients during cardiovascular evaluation in outpatient settings for risk stratification prior to coronary angiography.

Evaluation of the neurotoxicity of the polyethylene glycol hydrogel dural sealant.

AIM Although polyethylene glycol (PEG) is a neutral, biocompatible hydrophilic polymer recognized for its lack of interaction with biological barrier, its neurotoxicity has not been clearly identified in neurosurgery. This study is constructed to evaluate the possible neurotoxicity of a PEG hydrogel dural sealant. MATERIAL AND METHODS After a burrhole was opened in the left parietal bone of the twenty five Wistar albino rats, the dura mater and cerebral cortex were incised and the experimental material (activated polyethylene glycol and polyethylene imine) was sprayed into the burrhole. Then brain tissues were harvested for histopathological and biochemical studies at 72 hours to investigate the acute stage changes and on 15th day to evaluate the chronic stage changes. RESULTS There were statistically significant differences among the groups regarding the comparison of the values of the PMNL cell infiltration grades, gliosis and congestion in both acute and chronic stages. However, the values of the MNL cell infiltration grades, edema and fibrin formation, lipid peroxidation levels of harvested brain tissues were similar in all groups. CONCLUSION Although this study did not present the detailed histopathological and biochemical evaluation results, it indicated that the application of the PEG-based hydrogel sealant was not associated with neurotoxicity, delayed healing, or degenerative changes.