Kinetic model of photosensitized homolysis of erythrocytes: multihit target theory

Fotosensitize edilmis eritrositlerdeki hemoliz hız kinetigini örnek sistem olarak kullanarak, hücre zarındaki fotosensitizasyon mekanizmasının açıklanması amaçlanmıstır. Fotohemolizin ısıga baglı olusan hasar (fotokimyasal safha) ve termal aktivasyonun (termal safha) birlikte olan etkisiyle olustugunu kabul eden “Çok Vuruslu HedefTeori” 'de; her safhadaki kinetik düzen özel vuru sayıları ile belirlenebilmektedir. Fotohemoliz hızı formülüyle hesaplanmıs olup, sistemde %50 hemoliz olması için gerekli olan karanlık inkübasyon zamanını, uygulanan ısık dozunu, protoporfirin konsantrasyonu , reaksiyon sabitini, ve ise ölçülen üssel degerleri belirtmektedir. Deneyde, pH 7.4, 10 mM tuzlu fosfat tamponda hazırlanan insan eritrositleri degisik konsantrasyonlarda protoporfirin IX ile fotosensitif hale getirilmis ve ısıga maruz bırakılarak gecikmis fotohemoliz ölçümleri yapılmıstır. Ayrıca gecikmis fotohemoliz verileri “ÇokVuruslu HedefTeori” kullanılarak incelenmistir. Fotohemoliz egrileri s-seklinde olup, düsük protoporfirin konsantrasyonu ve ısınlama zamanında t degeri daha uzamıs olarak ölçülmüstür. Gecikmis fotohemoliz ölçümlerinde, fotohemoliz hızının sogurulan ısınımın karesiyle orantılı oldugu belirlenmistir. Deneysel ve modelle hesaplanan fotohemoliz egrileri uyum içindedir. “Çok Vuruslu Hedef Teori” ile, fotohemoliz sonuçlarının karakterize edilmesi ve karsılastırması açısından önemli oldugu gösterilmistir. Bu kinetik modelle belirlenen degisik konsantrasyonda fotosensitif ajan ve ısık dozunun fotohemoliz egrileri üzerine olan etkisinin, ölçülen deneysel verilerle uyum içinde olması ile “ÇokVuruslu HedefTeori” desteklenmektedir.By using rate kinetics of photosensitized hemolysis of erythrocyte as a model system, understanding the mechanism of photosensitization on the cell membrane was purposed in this work. Photohemolysis required the combined effect of the light activated (photochemical stage) and thermal (thermal stage) process, and these stages can be represented by “MultihitTarget Theory”, defined with photochemical and thermal hit numbers. Photohemolysis rate was calculated by using where is the dark incubation time required for 50% hemolysis, L is the incident light dose, is the bound dye concentration, and are the “as measured” exponents, and g is the reaction constant. Erythrocyte suspension, which was prepared in pH 7.4 10 mM phosphate buffered saline, was photosensitized with various concentration of protoporphyrin IX and was irradiated by visible light. Then, delayed photohemolysis was measured for each sample, and data were analyzed using “MultihitTarget Theory”. Prolonged t values were measured on delayed photohemolysis curve (s-shaped) with low protoporphyrin IX concentration and irradiation time. Delayed photohemolysis measurements are indicative of second power dependence of the photohemolysis rate on the absorbed light energy. Photohemolysis data obtained from experiments and kinetic model calculations were in good agreement. “Multihit Target Theory” is important for characterizing and comparing photohemolysis results. The effects of various concentrations of photosensitizers and light doses on photohemolysis curve were analyzed with kinetic model. Thus, experimental data were in good agreement with recent kinetic model, based on “MultihitTarget Theory”

The effect of electromagnetic field (50 hz, 6mt) on rat liver and kidney

Modern teknolojinin giderek ilerlemesinin bir sonucu olarak, bir çok endüstriyel ve evsel elektrikli aletlerin kullanımı ile birlikte, insanlar bunlardan kaynaklanan manyetik alanlara daha fazla maruz kalmaktadır. Son yıllarda elektromanyetik alan (EMA) olusturan aletlerin etkileri bir çok deneysel çalısmaya konu olmus ve farklı sonuçlara ulasılmıstır. Bu çalısmada elektromanyetik alana maruz kalan sıçanlarda karaciger ve böbrek dokusunun incelenmesi amaçlanmıstır. Bu çalısmada ortalama 290 gram agırlıgında 20 adet eriskin erkek Wistar albino sıçan kullanıldı. Deney hayvanları, her birinde 10'ar sıçan bulunacak sekilde “deney grubu ve kontrol grubu” olmak üzere iki gruba ayrıldı. Deney grubu günde 2 saat, haftada 7 gün olmak üzere 8 hafta süreyle 6 militesla (mT) (50 Hz, alternatif akım) EMA'a maruz bırakıldı. Deney sırasında sıçanların bulundugu ortamın sıcaklıgı termometre ile, manyetik alan ise Teslametre (Phyme) ile sürekli kontrol edildi. deney baslangıcında ve deney sonunda hayvanların canlı agırlıkları kaydedildi. Deney sonunda ötenazi uygulanan sıçanlardan doku örnekleri alındı. Formalin solusyonunda tespit edilen karaciger ve böbrek doku örnekleri rutin histolojik doku takibinden sonra parafine gömüldü. Parafin bloklardan alınan 5µ kalınlıgındaki kesitler Hematoksilen-Eosin, Periodik Asit Schiff ve Masson trikrom ile boyandı. Isık mikroskobunda histopatolojik olarak degerlendirilen kesitler dejenerasyon, fokal nekroz, fibrozis gibi histolojik bulgular yönünden semikantitatif olarak skorlandı. Elde edilen tüm sayısal veriler Mann-WhitneyUtesti ile istatistiksel olarak degerlendirildi. Deney hayvanlarının deney süresindeki agırlık artısı yüzdeleri ile karaciger ve böbrek agırlıkları açısından deney ve kontrol grubu arasında istatistiksel bir farklılık saptanmadı. Deney ve kontrol gruplarının toplam histolojik skorları arasında anlamlı bir farklılık olmadıgı belirlendi. Elde edilen bulgular, uzun süre 6 mT (50 Hz, alternatif akım) manyetik alana maruz kalan sıçanların karaciger ve böbrek dokusunda histolojik bir degisiklige neden olmadıgını göstermistir.In the last few decades, various investigations have been performed in order to determine the possible biological effects of electromagnetic fields (EMF) generated by power lines and telecommunication technologies. The long-term exposure toEMFmay have been linked to various disorders and may affect different organs. The aim of this study was to investigate the effect of 6 millitesla (mT)AC (alternate current) EMF on the rat liver and kidney. Twenty adult maleWistar rats were divided into 2 groups; one group was exposed to 50 Hz, 6 mTAC electromagnetic field for 8 weeks, 2 hours per day, and the other sham exposed, meaning that all other experimental conditions were the same except for EMF exposure. After 8 weeks, all subjects were sacrificed, livers and kidneys were removed and weighed. For histopathological examination, samples were fixed in 10% buffered formalin, embedded in paraffin, and then cut and stained with hematoxylin-eosin, PAS and Masson's trichrome. The histological samples were evaluated using the semi-quantitative scoring. Mann Whitney U test was applied for statistical analysis. For each animal the difference in body weight was calculated from the weight at the beginning of the experiment (day 0) and the weight at termination (day 56). The body weight gain of exposed group was less than that of the control group, but there was no significant difference between the two groups. The absolute and relative liver and kidney weights did not show any significant difference between the EMF exposed and sham exposed rats. Microscopic examination of liver and kidney samples revealed no significant differences between the EMF exposed and sham exposed rats. Present results show that whole body exposure to 50 Hz, 6 mT AC EMF doesn't cause gross and histological lesions on rat liver and kidney attributed to magnetic field exposure

Protoporphyrin IX-loaded magnetoliposomes as a potential drug delivery system for photodynamic therapy: Fabrication, characterization and in vitro study

Protoporphyrin IX (PpIX) is a well-known photosensitizer that has great potential for use in photodynamic therapy (PDT). However, aggregation behavior of PpIX in neutral water makes it inappropriate for physiological studies. PpIX-loaded magnetoliposomes (MLs) were fabricated to increase PpIX biocompatibility. PpIX-loaded ML physical properties were characterized, and PpIX-loaded ML drug release behavior was investigated under the influence of an external magnetic field and heat. Toxicity and photodynamic effects of the complex were also examined using in vitro experiments with MCF-7 human breast cancer cells. The magnetoliposomes were prepared with DPPC, DSPE-PEG2000 lipids and Fe3O4 nanoparticles. The toxicity and in vitro photodynamic effects of the PpIX-loaded MLs at various concentrations were studied using the MCF-7 cell line.TÜBİTAk (grant no: 112S958); Adnan Menderes University (grant no: TPF-13014

Effects of Low-Dose Citicoline on the Electrical Conduction Function of the Crushed Sciatic Nerve of Rats

Introduction: Citicoline has therapeutic and beneficial effects in a variety of neurologic disorders and neurodegenerative diseases. The aim of this study was to examine the beneficial effects of low doses of citicoline for the early period of administration in rat sciatic nerve crush injury by using electrophysiological and biochemical approaches. Methods: Thirty-two adult male Wistar rats were divided into four groups (n = 8 in each) and treated as follows: sham-operated (intact, saline), control (crushed sciatic nerve, saline), 50C (crushed sciatic nerve, 50 mg/kg citicoline), and 250C (crushed sciatic nerve, 250 mg/kg citicoline). At the end of the 7-day experimental period, motor nerve conduction velocities (MNCVs) were determined using in vivo electrodes and fresh rat blood was collected for biochemical analysis. Results: MNCVs were significantly reduced in crushed sciatic nerve of rats but significantly increased after 7 days of citicoline administration. Improved electrophysiological recovery in the citicoline groups was significant when compared to the control group. In addition, citicoline exacerbated the decrease in total glutathione level and glutathione reductase and catalase activities but decreased malondialdehyde levels compared to the control group. Conclusion: Results presented in this paper suggest that low doses of citicoline for the early period of administration have a promotional effect on improving the electrical conduction function of the sciatic nerve

Novel approaches for covid-19 diagnosis and treatment: a nonsystematic review

Since COVID-19 pandemic has been continuously rising and spreading, several original contributions and review articles on COVID-19 started to appear in the literature. The review articles are mainly focus on the current status of the pandemic along with current status of the corona diagnosis and treatment process. Due to some disadvantages of the currently used methods, the improvement on the novel promising diagnosis and treatment methods of corona virus is very important issue. In this review, after briefly discussing the status of current diagnosis and treatment methods, we present to the scientific community, novel promising methods in the diagnosis and treatment of COVID-19. As with other novel approaches, first, the diagnosis potential of mass spectroscopy and optical spectroscopic methods such as UV/visible, infrared, and Raman spectroscopy coupled with chemometrics will be discussed for the corona virus infected samples based on the relevant literature. In vibrational spectroscopy studies, due to complexity of the data, multivariate analysis methods are also applied to data. The application of multivariate analysis tools that can be used to extract useful information from the data for diagnostic and characterisation purposes is also included in this review. The reviewed methods include hierarchical cluster analysis, principal component analysis, linear and quadratic discriminant analysis, support vector machine algorithm, and one form of neural networks namely deep learning method. Second, novel treatment methods such as photodynamic therapy and the use of nanoparticles in the in-corona virus therapy will be discussed. Finally, the advantages of novel promising diagnosis and treatment methods in COVID-19, over standard methods will be discussed. One of the main aims of this paper is to encourage the scientific community to explore the potential of this novel tools for their use in corona virus characterization, diagnosis, and treatment

Early Alterations in Bone Characteristics of Type I Diabetic Rat Femur: A Fourier Transform Infrared (FT-IR) Imaging Study

Alterations in microstructure and mineral features can affect the mechanical and chemical properties of bones and their capacity to resist mechanical forces. Controversial results on diabetic bone mineral content have been reported and little is known about the structural alterations in collagen, maturation of apatite crystals, and carbonate content in diabetic bone. This current study is the first to report the mineral and organic properties of cortical, trabecular, and growth plate regions of diabetic rat femurs using Fourier transform infrared (FT-IR) microspectroscopy and the Vickers microhardness test. Femurs of type I diabetic rats were embedded into polymethylmethacrylate blocks, which were used for FT-IR imaging and microhardness studies. A lower mineral content and microhardness, a higher carbonate content especially labile type carbonate content, and an increase in size and maturation of hydroxyapatite crystals were observed in diabetic femurs, which indicate that diabetes has detrimental effects on bone just like osteoporosis. There was a decrease in the level of collagen maturity in diabetic femurs, implying a decrease in bone collagen quality that may contribute to the decrease in tensile strength and bone fragility. Taken together, the findings revealed alterations in structure and composition of mineral and matrix components, and an altered quality and mechanical strength of rat femurs in an early stage of type I diabetes. The results contribute to the knowledge of structure-function relationship of mineral and matrix components in diabetic bone disorder and can further be used for diagnostic or therapeutic purposes

Comparison of the Effects of Electroacupuncture and Melatonin on Nerve Regeneration in Experimentally Nerve-Damaged Rats

Background : Development of methods to accelerate nerve regeneration in peripheral nerve damage is important. Electroacupuncture is a new therapeutic method that combines traditional acupuncture with modern electrotherapy. Melatonin has been shown to reduce nerve damage. Objectives: In this study, we aimed to determine and compare the therapeutic effects of electroacupuncture and melatonin on rat sciatic nerve injury. Methods : A total of 56 adult male Wistar Albino rats were divided into four study groups with 14 animals in each group: intact control (group I), subcutaneous saline (group II), subcutaneous melatonin (group III), and electroacupuncture (group IV). Surgical procedure including unilateral (right) sciatic nerve injury was applied to groups II, III, and IV. Saline and melatonin started immediately after surgery for six weeks, while electroacupuncture was given two weeks after surgery for 3 weeks. Functional and histological assessments were used as outcome measurements. Results : Sciatic nerve damage caused a significant decrease in nerve conduction velocity. Both electroacupuncture treatment and melatonin treatment significantly increased the nerve conduction velocity. Both sciatic functional recovery and histological regeneration were faster in these treatment groups compared to the saline. However, no significant difference was observed between the two treatment groups. Conclusion : Electroacupuncture and melatonin are promising alternative treatment strategies for peripheral nerve damage and can be examined in detail in future studies

CCDC 2065533: Experimental Crystal Structure Determination

Related Article: Ebube E. Oyeka, Ilknur Babahan, Bernard Eboma, Kenechukwu J. Ifeanyieze, Obinna C. Okpareke, Esin P. Coban, Ali Özmen, Burak Coban, Mehran Aksel, Namık Özdemir, Tatiana.V. Groutso, Jude I. Ayogu, Ufuk Yildiz, Mehmet Dinçer Bilgin, H. Halil Biyik, Briana R. Schrage, Christopher J. Ziegler, Jonnie N. Asegbeloyin|2021|Inorg.Chim.Acta|528|120590|doi:10.1016/j.ica.2021.12059

CCDC 2012502: Experimental Crystal Structure Determination

Related Article: Ebube E. Oyeka, Ilknur Babahan, Bernard Eboma, Kenechukwu J. Ifeanyieze, Obinna C. Okpareke, Esin P. Coban, Ali Özmen, Burak Coban, Mehran Aksel, Namık Özdemir, Tatiana.V. Groutso, Jude I. Ayogu, Ufuk Yildiz, Mehmet Dinçer Bilgin, H. Halil Biyik, Briana R. Schrage, Christopher J. Ziegler, Jonnie N. Asegbeloyin|2021|Inorg.Chim.Acta|528|120590|doi:10.1016/j.ica.2021.12059