Ant Colony Optimization Based Feature Selection Method for QEEG Data Classification

Objective

Many applications such as biomedical signals require selecting a subset of the input features in order to represent the whole set of features. A feature selection algorithm has recently been proposed as a new approach for feature subset selection.

Methods

Feature selection process using ant colony optimization (ACO) for 6 channel pre-treatment electroencephalogram (EEG) data from theta and delta frequency bands is combined with back propagation neural network (BPNN) classification method for 147 major depressive disorder (MDD) subjects.

Results

BPNN classified R subjects with 91.83% overall accuracy and 95.55% subjects detection sensitivity. Area under ROC curve (AUC) value after feature selection increased from 0.8531 to 0.911. The features selected by the optimization algorithm were Fp1, Fp2, F7, F8, F3 for theta frequency band and eliminated 7 features from 12 to 5 feature subset.

Conclusion

ACO feature selection algorithm improves the classification accuracy of BPNN. Using other feature selection algorithms or classifiers to compare the performance for each approach is important to underline the validity and versatility of the designed combination.     

Thrombin activatable fibrinolysis inhibitor in Behçet's disease

INTRODUCTION: Thrombin activatable fibrinolysis inhibitor (TAFI) is a procarboxypeptidase downregulating plasmin formation, thereby causing a tendency for thrombosis development. Since, Beh?et's disease (BD) is a systemic vasculitis, which is commonly complicated by arterial and venous thrombosis, we aimed to find out plasma TAFI levels in BD, compared with healthy controls. We also searched whether plasma TAFI levels were significantly different between Beh?et's subgroups with and without thrombosis. MATERIALS AND METHODS: In this study, 105 BD patients (M/F: 64/41; mean age 36+/-1 years), followed up by Ege University Rheumatology Department were enrolled. The exclusion criteria were hemophilia, hyperlipidemia, diabetes mellitus, hepatic diseases renal failure, antiphospholipid positivity, oral contraceptive use and pregnancy. Age-and sex-matched healthy controls (n=53) were also included. Plasma TAFI levels were measured by ELISA. Since TAFI is also an acute-phase reactant, we also measured other inflammatory markers such as C-reactive protein (CRP). RESULTS: Plasma TAFI levels were significantly higher in Beh?et's patients (91.1+/-7.4 ng/ml) compared with healthy controls (14.3+/-4.5 ng/ml) (P<0.001), but there were no significant difference between the subgroups with and without thrombosis. In BD, there was no correlation between plasma TAFI levels and CRP. CONCLUSIONS: Regardless of manifest thrombosis, plasma TAFI levels in BD were significantly higher than in healthy controls. High TAFI levels might possibly contribute to the thrombotic tendency in BD. Future studies investigating TAFI gene polymorphism and functional activity are clearly needed, to clarify the exact role of TAFI in Beh?et's thrombosis.     

The plasma levels of activated thrombin activatable fibrinolysis inhibitor and thrombomodulin in Behçet Disease and their association with thrombosis

Objective

To investigate the plasma levels of activated thrombin activatable fibrinolysis inhibitor (aTAFI) and thrombomodulin (TM) in Behçet disease (BD) and their relationship with thrombosis.

Methods

Plasma aTAFI and TM levels were measured by ELISA in 89 patients with BD (18 having venous thrombosis) and in 86 healthy controls.

Results

Compared with healthy controls, the BD group had significantly lower levels of aTAFI (13.49 ± 8.88 µg/ml vs. 26.76 ± 11.57 µg/ml, p < 0.0001) and significantly higher levels of TM (3.26 ± 1.85 ng/ml vs. 2.6 ± 0.69 ng/ml, p = 0.0003). Neither aTAFI, nor TM levels differed significantly between BD patients with and without thrombosis (p > 0.05). Despite a tendency to positive correlation (r = 0.37, p = 0.0004) between plasma levels of aTAFI and TM in healthy controls, there was a tendency for negative correlation (r = -0.51, p < 0.0001) between these two parameters in BD patients.

Conclusion

The plasma aTAFI and TM levels do not seem to be related with the presence of thrombosis observed in BD. Increased plasma TM levels in BD may simply reflect endothelial cell activation and dysfunction.     

Mycobacterial infection of intraparenchymal bronchogenic cysts

Bronchogenic cysts (BCs) may rarely cause some interesting and unusual complications. Although infection is a common complication of BCs, there are only two patients with BC infected with mycobacterium in English literature. Two intraparenchymal BCs infected with mycobacterium are presented here as unusual complications. Cystectomy was performed for the cysts. They were given antituberculosis treatment. No complication or recurrences were detected in follow up period.     

Universal Markers of Thyroid Malignancies: Galectin-3, HBME-1, and Cytokeratin-19

Difficulties in diagnosis of thyroid lesions, even with histologic analysis, are well known. This study has been carried on to evaluate the role of immunohistochemical markers including galectin-3, Hector Battifora mesothelial cell-1 (HBME-1), and cytokeratin-19 in the diagnosis and differential diagnosis of benign and malignant thyroid lesions. The expressions of galectin-3, HBME-1, and cytokeratin-19 were tested in formalin-fixed, paraffin-embedded tissues from 458 surgically resected thyroid lesions including non-neoplastic and neoplastic lesions. Immunostaining with standard avidin–biotin complex technique was performed by using monoclonal antibodies. In malignant neoplastic thyroid lesions, galectin-3, HBME-1, and cytokeratin-19 were diffusely expressed in general. Diffuse expression rates of these three markers were 72.3% (47/65), 70.7% (46/65), and 76.9% (50/65), respectively. The use of galectin-3, HBME-1, and cytokeratin-19 may provide significant contributions in the differential diagnosis of malignant thyroid tumors. Although focal galectin-3, HBME-1, and cytokeratin-19 expression may be encountered in benign lesions, diffuse positive reactions for these three markers are characteristic of malignant lesions. It has concluded that cytokeratin-19 alone and its combinations with other markers were more sensitive in accurate diagnosis of papillary carcinoma than the other combinations; meanwhile, there were similar results for follicular carcinomas with HBME-1 alone and its combinations.     

The association between inherited thrombophilias and pregnancy-related hypertension recurrence

Purpose  

The aim of this study was to determine the association between inherited thrombophilias and pregnancy-related hypertension recurrence.     

Comparative genomic hybridization in ganglioneuroblastomas.

The ganglioneuroblastoma are rare lesions with widespread neuronal differentiation that have been classified as intermediate stages between neuroblastoma and ganglioneuroma. To identify overall chromosome aberrations in ganglioneuroblastoma, we performed comparative genomic hybridization. All of the five tumor samples were found to exhibit multiple gains involving different chromosomal regions. Chromosomal gains displayed by chromosomes and chromosome loci were 2p25 approximately pter (60%), 5p15.1 approximately p15.3 (60%), 7 (60%), 13q22 approximately q31 (60%), and 22 (60%), which were detected as minimal common regions in all five tumor samples. Chromosome 22 gain, which had not been reported in neuronal tumors before, and novel site 13q22 approximately q31 may be considered to play an important role in progression and differentiation of ganglioneuroblastoma.