Fractal dimension: analyzing its potential as a neuroimaging biomarker for brain tumor diagnosis using machine learning

Purpose: The main purpose of this study was to comprehensively investigate the potential of fractal dimension (FD) measures in discriminating brain gliomas into low-grade glioma (LGG) and high-grade glioma (HGG) by examining tumor constituents and non-tumorous gray matter (GM) and white matter (WM) regions.Methods: Retrospective magnetic resonance imaging (MRI) data of 42 glioma patients (LGG, n = 27 and HGG, n = 15) were used in this study. Using MRI, we calculated different FD measures based on the general structure, boundary, and skeleton aspects of the tumorous and non-tumorous brain GM and WM regions. Texture features, namely, angular second moment, contrast, inverse difference moment, correlation, and entropy, were also measured in the tumorous and non-tumorous regions. The efficacy of FD features was assessed by comparing them with texture features. Statistical inference and machine learning approaches were used on the aforementioned measures to distinguish LGG and HGG patients.Results: FD measures from tumorous and non-tumorous regions were able to distinguish LGG and HGG patients. Among the 15 different FD measures, the general structure FD values of enhanced tumor regions yielded high accuracy (93%), sensitivity (97%), specificity (98%), and area under the receiver operating characteristic curve (AUC) score (98%). Non-tumorous GM skeleton FD values also yielded good accuracy (83.3%), sensitivity (100%), specificity (60%), and AUC score (80%) in classifying the tumor grades. These measures were also found to be significantly (p < 0.05) different between LGG and HGG patients. On the other hand, among the 25 texture features, enhanced tumor region features, namely, contrast, correlation, and entropy, revealed significant differences between LGG and HGG. In machine learning, the enhanced tumor region texture features yielded high accuracy, sensitivity, specificity, and AUC score.Conclusion: A comparison between texture and FD features revealed that FD analysis on different aspects of the tumorous and non-tumorous components not only distinguished LGG and HGG patients with high statistical significance and classification accuracy but also provided better insights into glioma grade classification. Therefore, FD features can serve as potential neuroimaging biomarkers for glioma

Supercritical fluid extraction of Eucalyptus globulus bark: a promising approach for triterpenoid production

Eucalyptus bark contains significant amounts of triterpenoids with demonstrated bioactivity, namely triterpenic acids and their acetyl derivatives (ursolic, betulinic, oleanolic, betulonic, 3-acetylursolic, and 3-acetyloleanolic acids). In this work, the supercritical fluid extraction (SFE) of Eucalyptus globulus deciduous bark was carried out with pure and modified carbon dioxide to recover this fraction, and the results were compared with those obtained by Soxhlet extraction with dichloromethane. The effects of pressure (100-200 bar), co-solvent (ethanol) content (0, 5 and 8% wt), and multistep operation were studied in order to evaluate the applicability of SFE for their selective and efficient production. The individual extraction curves of the main families of compounds were measured, and the extracts analyzed by GC-MS. Results pointed out the influence of pressure and the important role played by the co-solvent. Ethanol can be used with advantage, since its effect is more important than increasing pressure by several tens of bar. At 160 bar and 40 degrees C, the introduction of 8% (wt) of ethanol greatly improves the yield of triterpenoids more than threefold

Sinteza i preliminarna ispitivanja antikonvulzivnog djelovanja derivata benzotiazol-2-il tiadiazola

Various N-(5-chloro-6-substituted-benzothiazol-2-yl)-N\u27-(substituted phenyl)-[1,3,4]thiadiazole-2,5-diamines (5a-t) were designed and synthesized starting from substituted acetophenones. Structures of all the compounds were confirmed on the basis of spectral and elemental analyses. All the newly synthesized compounds were screened for their anticonvulsant activity and were compared with the standard drug phenytoin sodium. Interestingly, all the compounds showed protections against seizures in the range 50-100 % indicative of the promising nature of the compounds against the seizure spread. Compounds 5b and 5c showed complete protection against MES induced seizures.U radu je opisano dizajniranje i sinteza različitih N-(5-klor-6-supstituiranih-benzotiazol-2-il)-N\u27-(supstituiranih fenil)-[1,3,4]tiadiazol-2,5-diamina (5a-t) polazeći od odgovarajućih acetofenona. Strukture spojeva određene su na temelju spektroskopskih podataka i elementarne analize. Ispitano je antikonvulzivno djelovanje svih novosintetiziranih spojeva i uspoređeno s djelovanjem natrijeve soli fenitoina. Spojevi 5b i 5c pružaju potpunu zaštitu od konvulzija uzrokovanih MES-om, a svi spojevi štite od konvulzija u rasponu od 50 do 100 %

Synthesis of Tetrahydro-2H-[1,3,5]thiadiazine-5-(4-pyridylcarboxamido)-2-thione with antitubercular activity

3-Substituted-5-(4-pyridylcarboxamide)tetrahydro-2H-[1,3,5]thiadizine-2-thione derivatives (1-9) were synthesized as derivatives of isoniazid (INH) to overcome the resistance developed with its therapeutic use. The structures were confirmed by their spectral and elemental analyses data. These derivatives revealed higher lipophilicity compared with INH. The antimycobacterial activity of the synthesized compounds and INH was evaluated in vitro against Mycobacterium tuberculosis H37Rv at 6.25 µg/ml in BACTEC 12B medium using the BACTEC 460 radiometric system. The derivatives exhibited antitubercular activity