Browsing by Subject "Drugs"

Now showing 1 - 3 of 3

Open Access
Deepside: predicting drug side effects with deep learning
(2019-09) Üner, Onur Can
Drug failures due to unforeseen adverse effects at clinical trials pose health risks for the participants and cause substantial financial losses. Side effect prediction algorithms, on the other hand, have the potential to guide the drug design process. LINCS L1000 dataset provides a vast resource of gene expression profiles across different cell lines that are induced with different dosages taken at different time points. The state-of-the-art approach in the literature relies on high-quality experiments in LINCS L1000 and discard a large portion of the recorded experiments. In this study, we investigate whether more information can be extracted from this remaining set of experiments with a deep learning-based approach. We experiment with 6 different deep learning architectures that use (i) gene expression data from the LINCS L1000 project, (ii) chemical structure fingerprints of drugs, (iii) SMILES string representation of drug structure, and (iv) the atomic structure of the drug molecules. The multilayer perceptron (MLP) based model which uses chemical structures and gene expression features achieve 88% micro- AUC and 79% macro-AUC, thus offering better performance in comparison to the state-of-the-art studies on side effect prediction. We observe that the chemical structure is more predictive than the gene expression profiles despite the fact that the features are extracted with different deep learning models. Finally, the convolutional neural network-based model that uses only SMILES strings of the drugs provides 82% macro-AUC, and 88%micro-AUC improvements, better performing than the models that use gene expression and chemical structure features simultaneously.
Open Access
Encapsulation of food additives and drugs by cyclodextrin functionalized electrospun nanofibers
(2020-06) Yıldız, Zehra İrem
Electrospun nanofibers attract attention of many areas including food and pharmaceutical industries thanks to their unique physical/mechanical properties like large surface area-to-volume ratio, nanoporous structure, design flexibility and lightweight. Although, in general polymers are used for fabrication of electrospun nanofibers, it is also possible to obtain electrospun nanofibers purely from cyclodextrins (CDs). CDs with truncated cone shape structure are attractive host molecules for the formation of host-guest type inclusion complexes (ICs) with variety of appropriate guest molecules. Creating ICs with CDs causes remarkable enhancement at the properties of the guest molecule, and so CDs have wide range of applications in many areas including food and pharmaceutical industries. In this thesis, polymer-free electrospun nanofibers from CD-ICs of some food additives and drugs were produced. Firstly, four food additives, menthol, carvacrol, cinnamaldehyde and beta-carotene were encapsulated by electrospun CD nanofibers. Afterwards, the solubility, heat/light stability, antibacterial/antioxidant activity of the materials were investigated to observe the effects of encapsulation by CD nanofibers on the food additives. Secondly, electrospun CD-IC nanofibers of three types of drugs, sulfisoxazole, paracetamol and catechin were produced. Since one of the most critical point for drug bioavailability is its solubility in water, the obtained electrospun drug/CD-IC nanofibers were mainly investigated in terms of change in their solubility. In the light of analyses, it can be concluded that, main drawbacks of food additives and drugs like high volatility, low solubility and low stability were reduced or removed; besides, their properties such as antioxidant and antibacterial activities were enhanced or preserved.
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Narkotik ve Kaçakçılık İstihbarat Dairelerinin kara kutusu: Atilla Aytek
(Bilkent University, 2022) Metin, Selin Hira; Çınar, Dilara; Gençcelep, Senanur; Coşan, Umut; Kartal, Fırat
1960-1990 yılları arasında Türkiye’de ve Dünya’da uyuşturucu ve kaçakçılık olaylarında büyük bir artış görülmüştü. Bu artışa engel olmak adına Türkiye’de birçok operasyon yapıldı. Bu operasyonlarda Atilla Aytek en önemli isimlerden biri oldu. 1968-1988 yılları arasında Emniyet Müdürlüğü’nde Narkotik Şubede ve ardından Kaçakçılık ve İstihbarat Daire Başkanlığı’nda çalışan Aytek, bu süreç içerisinde birçok başarılı operasyona imza attı. Bu çalışmada Atilla Aytek’in hayatı, Emniyet’e katkıları, kariyerindeki önemli olayları ve hakkındaki soruşturmaları anlatılmıştır. Bu konular, 1968-1988 yılları arasında Türkiye’nin uyuşturucu ve kaçakçılığa karşı verdiği mücadeleyi anlamak için çok önemlidir.