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Herein, we report the crystal structure of 2,7-dichlorofluorescein methyl ester (DCF-ME) and its fluorescence response to hydroxyapatite binding. The reported fluorophore is very selective for staining the bone matrix and provides turn-on fluorescence upon hydroxyapatite binding. The reported fluorophore can readily pass the cell membrane of the C2C12 cell line, and it is non-toxic for the cell line. The reported fluorophore DCF-ME may find applications in monitoring bone remodeling and microcalcification as an early diagnosis tool for breast cancer and age-related macular degeneration. more...

Colorectal cancer (CRC) has a poor prognosis and urgently needs better therapeutic approaches. 5-Aminolevulinic acid (ALA) induced protoporphyrin IX (PpIX) based photodynamic therapy (PDT) is already used in the clinic for several cancers but not yet well investigated for CRC. Currently, systemic administration of ALA offers a limited degree of tumour selectivity, except for intracranial tumours, limiting its wider use in the clinic. The combination of effective ALA-PDT and chemotherapy may provide a promising alternative approach for CRC treatment. Herein, theranostic Ag2S quantum dots (AS-2MPA) optically trackable in near-infrared (NIR), conjugated with endothelial growth factor receptor (EGFR) targeting Cetuximab (Cet) and loaded with ALA for PDT monotherapy or ALA/5-fluorouracil (5FU) for the combination therapy are proposed for enhanced treatment of EGFR(+) CRC. AS-2MPA-Cet exhibited excellent targeting of the high EGFR expressing cells and showed a strong intracellular signal for NIR optical detection in a comparative study performed on SW480, HCT116, and HT29 cells, which exhibit high, medium and low EGFR expression, respectively. Targeting provided enhanced uptake of the ALA loaded nanoparticles by strong EGFR expressing cells and formation of higher levels of PpIX. Cells also differ in their efficiency to convert ALA to PpIX, and SW480 was the best, followed by HT29, while HCT116 was determined as unsuitable for ALA-PDT. The therapeutic efficacy was evaluated in 2D cell cultures and 3D spheroids of SW480 and HT29 cells using AS-2MPA with either electrostatically loaded, hydrazone or amide linked ALA to achieve different levels of pH or enzyme sensitive release. Most effective phototoxicity was observed in SW480 cells using AS-2MPA-ALA-electrostatic-Cet due to enhanced uptake of the particles, fast ALA release and effective ALA-to-PpIX conversion. Targeted delivery reduced the effective ALA concentration significantly which was further reduced with codelivery of 5FU. Delivery of ALA via covalent linkages was also effective for PDT, but required a longer incubation time for the release of ALA in therapeutic doses. Phototoxicity was correlated with high levels of reactive oxygen species (ROS) and apoptotic/necrotic cell death. Hence, both AS-2MPA-ALA-Cet based PDT and AS-2MPA-ALA-Cet-5FU based chemo/PDT combination therapy coupled with strong NIR tracking of the nanoparticles demonstrate an exceptional therapeutic effect on CRC cells and excellent potential for synergistic multistage tumour targeting therapy., Newton-Katip Çelebi Fund; British Council; Scientific and Technological Research Council of Turkey (TÜBİTAK) more...

Colorectal cancer (CRC) has a poor prognosis and urgently needs better therapeutic approaches. 5-Aminolevulinic acid (ALA) induced protoporphyrin IX (PpIX) based photodynamic therapy (PDT) is already used in the clinic for several cancers but not yet well investigated for CRC. Currently, systemic administration of ALA offers a limited degree of tumour selectivity, except for intracranial tumours, limiting its wider use in the clinic. The combination of effective ALA-PDT and chemotherapy may provide a promising alternative approach for CRC treatment. Herein, theranostic Ag more...

Bu çalışmanın amacı Türkiye Süper Lig’de mücadele eden Beşiktaş, Fenerbahçe, Galatasaray ve Trabzonspor takımlarının 30.09.2019 tarihi itibari ile kadrolarında bulunan futbolcularının finansal değerleri üzerinden varlığa dayalı menkul kıymetleştirme işlemi yapılmaya çalışmıştır. Kulüplerin kadrolarında bulunan futbolcular oynadıkları mevkiilere göre kaleci, defans, orta saha ve forvet mevkileri olmak üzere 4 mevkiiye göre sınıflandırılmıştır. Çalışma için transfermarkt sitesinin verileri kullanılmış, değerlemenin yapıldığı tarihten futbolcuların doğum tarihleri çıkartılması ile yaş-ay zamanına göre transfermarkt değeri bulunmuştur. Tüm futbolcular için 16 yaş 01 ay ve 37 yaş 12 ay arasında futbol oynadıkları varsayılmıştır. Transfermarkt sitesi futbolcu değerlemelerini sürekli yapmadığı için veri olmayan yaş-ay zaman dilimi için kübik spline (şerit) interpolasyon yöntemi ile belirlenen yaş aralıkları için tüm aylar için değerler tahmin edilmiştir. Eğri uydurma işlemi için Eviews 10 programı kullanılmıştır.Çalışmada 4 takım için de kaleci, defans, orta saha ve forvet mevkiinde oynayan futbolcuların değerlerinin en yüksek olduğu yaş-ay zamanı tespit edilmiştir. Transfermarkt verilerine göre Galatasaray takımı kadrosunda bulundurduğu futbolcular ile birlikte en değerli takım olduğu tespit edilmiştir. Ayrıca fonksiyon ile elde edilen verilere göre de tüm mevkiiler için en yüksek ortalamaların da Galatasaray takımına ait olduğu görülmüştür. Elde edilen verilere göre Trabzonspor takımının kaleci mevkii için menkul kıymetleştirme işlemi yapılmış ve bir örnek ile açıklanmaya çalışılmıştır., This study aims to Turkey Super League competetor Besiktas, Fenerbahce,Galatasaray and Trabzonspor based on the value of financial assets out of theplayers who team with a staff of date 30.09.2019 has tried to make thesecuritization process. The players in the clubs are classified according tothe positions they play in 4 positions; goalkeeper, defender, midfielder andforward. The data on the Transfermarkt website were used for the study and thevalue of the players birth date was subtracted from the date of the valuationby age-month time. It is assumed that for all players, they play footballbetween 16 years 01 months and 37 years 12 months. For the non-data age-monthtime period, values ​​were estimated for all months for the age rangesdetermined by cubic spline interpolation method, since the Transfermarktwebsite did not make continuous player evaluations. Eviews 10 program was usedfor curve fitting. In the study, age-month time of the players who played ingoalkeeping, defender, midfielder and striker positions for all 4 teams wasdetermined. According to data from Transfermarkt, Galatasaray team was found tobe the most valuable team along with the players it had in its squad. Inaddition, according to the data obtained by the function, the highest averagesfor all positions were also found to belong to Galatasaray team. According tothe data obtained, the Securitization process was performed for the goalkeepingposition of Trabzonspor team and tried to be explained with an example. more...

Medium-sized ynolides were prepared by the Lewis acid-mediated fragmentation of bicyclic γ-silyloxy-β-hydroxy-α-diazolactones in which the Cβ–Cγ bond is the ring fusion bond. Although these lactone fragmentation substrates reacted somewhat less efficiently than their carbocyclic counterparts, the fragmentation provided 11-membered ynolides in up to 84% yield. Unlike prior fragmentations of similar substrates, elevated temperatures were required to obtain optimum yields of the ynolide products. The ynolides reported herein have ring sizes of 10 or 11, which are the smallest reported to date. more...

Cyclic gamma-oxy-beta-hydroxy-alpha-diazo carbonyls undergo Lewis acid induced ring fragmentation to provide either ynoates or ynones tethered to an aldehyde, ketone, or ester. The fragmentation precursors are convenient to prepare by adding lithiated alpha-diazo carbonyls to alpha-oxy ketones. The fragmentation appears general and provides a variety of functional group-rich products in good to excellent yield. more...

A series of copolymers of N,N-morpholine-N-2-(ethoxycarbonyl)allyl allyl ammonium chloride, N,N-morpholine-N-2-(ethoxycarbonyl)allyl allyl ammonium bromide, N,N-piperidyl-N-2-(ethoxycarbonyl)allyl allyl ammonium chloride, N,N-morpholine-N-2-(t-butoxycarbonyl)allyl allyl ammonium bromide and diallyldimethylammonium chloride (DADMAC) with acrylamide (AAm) were prepared in water at 50-56 °C using 2,2'-azo-bis(2-amidinopropane)dihydrochloride (V-50). The ethyl ester monomers showed high cyclization efficiencies during copolymerizations. The tert-butyl ester derivatives showed high cross-linking tendencies. The molar fractions of allyl-acrylate monomers in the AAm: allyl-acrylate copolymers were higher than the one of DADMAC in the AAm:DADMAC copolymers. The intrinsic viscosities of the copolymers measured in 0.09 M NaCl ranged from 2.5 to 7.5 dL/g. more...

The presented method gives access to 10 and 11 membered ynolides, which are the smallest reported to date.

We report the synthesis of a water-soluble flavin polymer using ATRP, whereby the oligoethylene glycol backbone provides both a local hydrophobic environment and redox tuning of the flavin moiety typical of flavoenzyme prototypes. more...

The reaction of various bicyclic diazoketones of type (I) or (III) is mediated by SnCl4 to provide cyclic 2-alkynones with a ring size up to 12 C-atoms.

Bicyclic γ-silyloxy-β-hydroxy-α-diazoketones, in which the Cβ-Cγ bond is the ring fusion bond, productively fragment when treated with tin(IV) chloride to provide medium-sized cyclic 2-alkynones. This method provides good to excellent yields of 10-, 11-, and 12-membered alkynone products. more...

Nowadays, most of the basic web services use instant location information for providing suitable content to smartphone users. However, more intelligent smartphone applications such as context-based search and advertising, early warning systems and city-wide sensing applications may require additional information about smartphone users such as their mobility profiles. To meet more personalized demand of these applications we propose TRACK ME: A new web-based framework for smartphone applications with personalized lightweight mobility service as well as location tracking and mobility profile construction. We showed that our personalized mobility service supports different smartphone applications and it is lightweight enough to provide fast access to the mobility profiles of smartphone users. We illustrate the benefits of our mobility service on two smartphone applications: location prediction and air pollution exposure risk estimation. more...

Cyclic γ-oxy-β-hydroxy-α-diazo carbonyls undergo Lewis acid induced ring fragmentation to provide either ynoates or ynones tethered to an aldehyde, ketone, or ester. The fragmentation precursors are convenient to prepare by adding lithiated α-diazo carbonyls to α-oxy ketones. The fragmentation appears general and provides a variety of functional group-rich products in good to excellent yield. more...

We have used mixed monolayer protected gold clusters (MMPCs) to provide flavoenzyme model systems with a high affinity and ability to modulate cofactor reduction potential.