İstanbul Sağlık ve Teknoloji Üniversitesi Kurumsal Akademik Arşivi
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Synergistic effects of ozone with doxorubicin on the proliferation, apoptosis and metastatic profile of luminal-B type human breast cancer cell line
No full textObjective Luminal-B type human breast cancer cell line (BT-474) to assess the synergistic effects of ozone applied after chemotherapeutic treatment with various dosages of doxorubicin, and compare the results with the effects on L929 fibroblast cell line. Methods Doxorubicin (1–50 M) was added to each cell lines and left to sit for 24 h at 37 °C. Then, as combination groups, half of the groups were incubated with 30 g/mL ozone for 25 min. Tumor necrosis factor alpha (TNF-α), transforming growth factor beta (TGF-β), and matrix metalloproteinase-2 and − 9 (MMP-2 and MMP-9) levels were measured using the MTT test, flow cytometry, and immunocytochemistry, respectively. Results When compared to simply doxorubicin-applied cells without ozone treatment, each dose of doxorubicin + ozone treatment considerably boosted L929 viability but significantly decreased BT-474 viability. Additionally, the combination increased the apoptotic impact of doxorubicin on BT-474 but not L929 (P < 0.001). TGF-, MMP-2, and MMP-9 levels of L929 after combination were substantially higher than those of the other groups (P < 0.01). Doxorubicin's effect on BT-474's protein levels, which had significantly decreased in comparison to those of the other groups, was reversed by the combination treatment (P < 0.05). Conclusion Doxorubicin's anti-proliferative and apoptotic effects were enhanced by ozone treatment in BT-474 cells, but it also repaired and healed healthy fibroblast cells that had been harmed by the cytotoxicity of the chemotherapy drug. If doxorubicin and ozone treatment are coupled, BT-474 cells may develop resistance to it through expressions of TNF-α, TGF-β, MMP-2, and MMP-9
Mechanical shaft optimization: A study on static structural analysis and topological optimization in ansys
No full textShafts are extensively used in engineering fields, serving roles in power transmission and rotational movement, thus holding significant importance. This study focuses on analyzing the structure of a selected shaft model derived from research. Subsequently, topology optimization is applied based on the obtained findings. ANSYS software is utilized for performing analysis and optimization analysis. Following the completion of these analyses, the results are thoroughly examined. The optimization process resulted in a reduction of about 2.65% in the maximum stress and approximately 2.46% decrease in the maximum strain, indicating improved mechanical performance. However, an increase of about 33.24% in maximum deformation was observed, which warrants further consideration. Most notably, the weight of the shaft decreased significantly by approximately 57.81%, resulting in the creation of a much lighter model. These outcomes highlight the potential of topology optimization, demonstrating the ability to create lighter and stronger models while utilizing resources efficiently. Consequently, it becomes imperative to explore these outcomes further by modifying selected parameters to achieve optimal results and enhance the model's performance. This study successfully showcases the potential of topology optimization, paving the way for the creation of lighter and stronger models in engineering applications
A century-long adventure of nutrition in diabetes: An assessment and transliteration of Dr. Mehmet Kâmil and Dr. Muzaffer’s What Should Diabetics Consume?
No full textKan şekeri seviyesinin anormal yüksekliği ile karakterize metabolik bir hastalık olan diyabetin beslenmeyle yakın ilişkisi yüzyıllardır bilinmektedir. Diyabette tıbbi beslenme tedavisine yönelik ilk bilimsel yaklaşımlar ise 20. yüzyılın başlangıcı itibariyle yoğunlaşmaktadır. Ancak, bu dönemin diyet önerileri ve klinik uygulamalarına ilişkin literatür oldukça sınırlıdır. Bu çalışmada, Türkiye Cumhuriyeti’nin ilk yıllarında Harf Devrimi henüz uygulama sürecindeyken, Osmanlı Türkçesiyle yazılan Şekerliler Ne Yemelidir? (İstanbul, 1929) adlı kitapçıktan edinilen bilgiler ışığında yaklaşık bir asır öncesindeki diyabetik tıbbi beslenme tedavisi incelenmiştir. Kitapçık, Şişli Etfal Hastanesinde Dâhiliye uzmanı olan Dr. Mehmed Kâmil (Berk) ile Cerrahpaşa Hastanesi diyabet uzmanı Dr. Muzaffer Şevki (Yener) Beyler tarafından yazılmıştır. Diyabet kitapçığı olarak hazırlanan eser, o dönemin tıbbi tecrübeleri çerçevesinde şeker hastalarının takip etmesi gereken beslenme önerilerini içermektedir. Bu çalışmada eserde yer alan bilgiler dönemin bilimsel literatürü ve günümüz uygulamaları ile karşılaştırılarak diyabette klinik beslenme tedavisinin günümüze dek değişimi değerlendirilmiştir. Ayrıca, eserin tam metni Türkçe’ye çevrilerek, yazarları hakkında da bilgi verilmiştir.Diabetes is a metabolic disease characterized by abnormally high blood sugar levels and has been known for centuries to be closely related to nutrition. The first scientific approaches to medical nutrition therapy regarding diabetes intensified at the beginning of the 20th century. However, the literature on dietary recommendations and clinical practices for this disease is quite limited. This study investigates medical nutrition therapy regarding diabetes from a century ago in light of information obtained from a booklet titled What Should Diabetics Eat? (Istanbul, 1929), which was published in Ottoman Turkish while the Alphabet Reform being implemented in the early years of the Turkish Republic. The booklet was written by Dr. Mr. Mehmet Kâmil, an internist at Şişli Etfal Hospital, and by Dr. Mr. Muzaffer, the physician at Galatasaray High School. The work was prepared as a diabetes booklet and includes nutritional recommendations that diabetic individuals should follow within the framework of the medical experience of that period. This study compares the recommendations given in the booklet both with the scientific literature of the period and with current practices and evaluates the changes that have occurred in clinical nutrition therapy regarding diabetes up until the present day. The present article also includes information about the authors of the booklet, as well as its full text in Latin characters
Yeşil kimyasal çözücüler
No full textSon yıllarda, tehlikeli çözücülerin çevre üzerindeki etkisine ilişkin farkındalık önemli ölçüde artmıştır. Bu etkiyi azaltmak ve çevreyi korumak için birçok gelişme hayata geçirilmiştir. Bir gelişme, gelecek nesillerin ihtiyaçlarını etkilemeden mevcut nesillerin ihtiyaçlarını karşılıyorsa, sürdürülebilir olarak kabul edilir. Hem endüstriyel hem de laboratuvar ölçeğinde kimyasal faaliyetleri içeren teknolojiler, sürdürülebilirliği etkileyen ana faktörler olarak kabul edilir. Önemli hacimlerde tehlikeli kimyasalların kullanıldığı laboratuvar deneyleri gibi kimyagerlerin küçük ölçekli faaliyetleri bile, kimyasal atıkların kontrolsüz bir şekilde imha edilmesi durumunda çevreyi olumsuz yönde etkileme potansiyeline sahiptir. Kimyasal faaliyetler (çevresel, biyolojik, klinik vb.) sonucu çevreyi ve doğrudan temas halinde olan kimyagerleri korumak için çeşitli önlemler geliştirilmiştir. “Yeşil kimya”, “çevreye zarar vermeyen kimya”, “temiz kimya” vb. gibi çeşitli terimler, kimyasal faaliyetlerin çevre dostu bir şekilde gerçekleştirilmesi ihtiyacını vurgulamak için tanımlanmıştır. Bu yaklaşımlar, reaktiflerin tüketimini ve atık oluşumunu en aza indirmeyi ve tehlikeli kimyasalları ortadan kaldırmayı hedefler. Bu çalışmada yeşil kimyanın 12 temel ilkesi ve bu ilkeler kapsamındaki yeşil çözücüler incelenmiştir
Maksiller premolar dişlerde farklı eğe sistemlerinin şekillendirme yeteneği: Bir mikro-bilgisayarlı tomografi çalışması
No full textAim: To evaluate the shaping ability of 4 file systems; WaveOne Gold (WOG; Dentsply Sirona), Reciproc Blue (RB; VDW), ProTaper Next (PTN; Dentsply Sirona) and TruNatomy (TRN; Dentsply Sirona) using micro-computed tomography (micro-CT) technology. Methodology: This study randomly separated twenty-four human maxillary premolars with two roots into four groups of 6 teeth. According to the manufacturer’s instructions, all root canal shaping was performed with WOG, RB, PTN, and TRN instruments. Micro-CT scanning was performed before and after preparation. The percentage of unprepared canal area, changing canal area (Δ canal area), percentage of changing canal area (%Δ canal area), changing canal volume (Δ canal volume), and percentage of changing canal volume (%Δ canal volume) were compared using one-way ANOVA and Welch’s ANOVA. At the same time, the 2D parameters (transportation and centering ability) were analyzed with the one-way ANOVA and Kruskal Wallis H tests. The level of significance was set at p 0.05). No differences in the Δ canal area, Δ canal volume, %Δ canal volume, Δ SMI, and %Δ SMI were observed between the four groups. The percentage of the unprepared area was higher in the TRN group compared to the other three file systems (p0.05). The %Δ canal area was significantly higher in the WOG group than in the TRN and PTN groups (p0.05). Conclusion: All systems used in this study had similar shaping effectivity without clinically significant errors. TRN touched the lowest percentage of canal surface, and regarding the %Δ canal area, WOG was significantly higher.Amaç: WaveOne Gold (WOG; Dentsply Sirona), Reciproc Blue (RB; VDW), ProTaper Next (PTN; Dentsply Sirona) ve TruNatomy (TRN; Dentsply Sirona) dört farklı eğe sisteminin şekillendirme kabiliyetlerini mikro-bilgisayarlı tomografi (mikro-BT) teknolojisi ile değerlendirmektir. Gereç ve Yöntem: Bu çalışmada, 24 adet iki köklü maksiller premolar dişler, 6 dişten oluşan rastgele dört gruba ayrıldı. Üretici talimatlarına göre, tüm kök kanal şekillendirmeleri WOG, RB, PTN ve TRN eğe sistemleri ile gerçekleştirildi. Preparasyondan önce ve sonra mikro-BT taraması yapıldı. Dokunulmamış kanal alanı yüzdesi, değişen kanal alanı (Δ kanal alanı), değişen kanal alanı yüzdesi (%Δ kanal alanı), değişen kanal hacmi (Δ kanal hacmi) ve değişen kanal hacmi yüzdesi (%Δ kanal hacmi) tek yönlü ANOVA ve Welch’in ANOVA’sı testleri kullanılarak karşılaştırıldı. Aynı zamanda tek yönlü ANOVA ve Kruskal Wallis H testleri ile iki boyutlu parametreler (transportasyon ve merkezleme yeteneği) analiz edilmiştir. Anlamlılık düzeyi p 0,05). Dört grup arasında Δ kanal alanı, Δ kanal hacmi, %Δ kanal hacmi, Δ SMI ve %Δ SMI açısından fark gözlenmedi. TRN grubunda kanal içi dokunulmamış alan yüzdesi diğer üç eğe sistemine göre daha yüksekti (p0,05). %Δ kanal alanı WOG grubunda TRN ve PTN gruplarına göre anlamlı olarak yüksekti (p0,05). Sonuç: Bu çalışmada kullanılan tüm eğe sistemleri, klinik olarak önemli hatalar olmadan benzer şekillendirme etkinliğine sahipti. TRN kanal yüzeyine en düşük yüzde ile dokundu ve %Δ kanal alanı ile ilgili olarak WOG önemli ölçüde daha yüksekti
Nanocomposite and nanohybrid gel polymer electrolytes for safe and high performing lithium metal batteries
No full textLithium-ion batteries (LIBs) have gained widespread popularity in the fields of portable electronics, electric vehicles, and grid storage due to their remarkable characteristics. These include their exceptional energy density, power density, and extended cycle life. The high energy density of LIBs allows them to store a significant amount of energy in a compact size, making them ideal for portable electronic devices. Additionally, their high power density enables them to deliver a substantial amount of power quickly, which is crucial for applications such as electric vehicles. Moreover, LIBs exhibit a long cycle life, meaning they can undergo numerous charge and discharge cycles without significant degradation in performance. This longevity makes them reliable and cost-effective for grid storage systems. Overall, the exceptional features of LIBs have propelled their extensive use in various industries, revolutionizing the way we power our devices and vehicles. The discovery of intercalation electrodes by Whittingham in the 1970s laid the foundation for LIB development. In the subsequent decades, Goodenough and his colleagues played a pivotal role by developing crucial cathode materials such as layered, spinel, and polyanion. Additionally, Yoshino's pioneering work involved the creation of the first safe LIB prototype, which employed LiCoO2 as the positive electrolde and carbon/graphite as the negative electrode. Since then, remarkable advancements have been achieved in increasing energy density, power density, cycle life, cost-effectiveness, and safety of lithium-ion batteries (Liu, 2021)
Global prevalence, cascade of care, and prophylaxis coverage of hepatitis B in 2022: a modelling study
No full textBackground The 2016 World Health Assembly endorsed the elimination of hepatitis B virus (HBV) infection as a public health threat by 2030; existing therapies and prophylaxis measures make such elimination feasible, even in the absence of a virological cure. We aimed to estimate the national, regional, and global prevalence of HBV in the general population and among children aged 5 years and younger, as well as the rates of diagnosis, treatment, prophylaxis, and the future burden globally. Methods In this modelling study, we used a Delphi process with data from literature reviews and interviews with country experts to quantify the prevalence, diagnosis, treatment, and prevention measures for HBV infection. The PRoGReSs Model, a dynamic Markov model, was used to estimate the country, regional, and global prevalence of HBV infection in 2022, and the effects of treatment and prevention on disease burden. The future incidence of morbidity and mortality in the absence of additional interventions was also estimated at the global level. Findings We developed models for 170 countries which resulted in an estimated global prevalence of HBV infection in 2022 of 3·2% (95% uncertainty interval 2·7–4·0), corresponding to 257·5 million (216·6–316·4) individuals positive for HBsAg. Of these individuals, 36·0 million were diagnosed, and only 6·8 million of the estimated 83·3 million eligible for treatment were on treatment. The prevalence among children aged 5 years or younger was estimated to be 0·7% (0·6–1·0), corresponding to 5·6 million (4·5–7·8) children with HBV infection. Based on the most recent data, 85% of infants received three-dose HBV vaccination before 1 year of age, 46% had received a timely birth dose of vaccine, and 14% received hepatitis B immunoglobulin along with the full vaccination regimen. 3% of mothers with a high HBV viral load received antiviral treatment to reduce mother-to-child transmission. Interpretation As 2030 approaches, the elimination targets remain out of reach for many countries under the current frameworks. Although prevention measures have had the most success, there is a need to increase these efforts and to increase diagnosis and treatment to work towards the elimination goals.John C Martin Foundation, Gilead Sciences, and EndHep2030
Architectural interior lighting
No full textArchitectural Interior Lighting is an essential guide to creating well-lit, visually appealing interior spaces. The book begins with an overview of light and color theory, lighting fundamentals, and design principles. It then covers artificial, natural, decorative, and professional lighting in interior design, as well as standards and regulations, controls and systems, sustainable lighting, energy efficiency, light pollution reduction, and the use of environmentally friendly materials. With a focus on practical applications and real-world examples, this book provides readers with the tools and knowledge necessary to achieve their design goals while considering the latest trends and techniques in the field. A valuable resource for professionals and students in architecture and lighting design, it will also appeal to anyone interested in creating visually stunning and functional interior spaces
Microstructure and mechanical performance of low-cost biomedical-grade titanium-316L alloy
No full textA 316L stainless steel (SS) alloy was developed with 1, 3, and 5 vol% titanium (Ti) reinforcement using the powder injection molding route, representing a low-cost option for biomedical implants. The investigation encompassed 1300 °C, 1350 °C, and 1380 °C sintering temperatures to ascertain the optimal physical and mechanical properties. Both sintering temperature and Ti influenced sintered density, and Ti mitigated the deleterious effects of residual carbon. At higher sintering temperatures, carbon and silicon tended to migrate and accumulate at the brink of Ti, leading to the formation of intermetallic compounds and increased brittleness. Dispersed Ti particles within the 316L matrix acted as nucleation sites and enhanced solid solubility with improved density. An astounding 96.11 % sintered density was achieved at 3 vol% Ti sample sintered at 1380 °C. During the tensile test, 5 vol% Ti at 1380 °C exhibited a low modulus of 58.9 GPa, which is highly desirable for orthopedic implant application. The XRD, SEM, tensile test, and nano-indentation results collectively provide evidence of beta-titanium formation during the sintering process. Conversely, the sample incorporating 3 vol% titanium, sintered at 1380 °C, demonstrated a balanced performance, showcasing 432.94 ± 12.8 MPa ultimate tensile strength, 3.06 ± 0.17 % elongation, 74.2 GPa modulus, and 322 MPa and 423 MPa 0.2 % offset flexural and compressive yield strengths, respectively. Notably, an improvised wear resistance test underscored its aptitude for sliding wear resistance, solidifying its potential as a promising candidate for biomedical implants.Universiti Teknologi PETRONAS (UTP) -- Grant No. 015LC0-336
Histological staining technics for identifying various structures for histological assessment of bone and cartilage healing
No full textBone and cartilage regeneration are challenging topics which the scientists are constantly looking for new approaches to eliminate current limitations of the traditional therapeutic methods which are being used. Cellular therapy and use of biomaterials for that purpose is providing encouraging results, especially in cases like osteoarthritis and bone healing. In such studies, the histological assessment of the healing of corresponding tissues are vital to determine to see if the developed method is indeed resulted with positive outcomes or not. Each tissue has some different distinctive structures that must be investigated during the healing process. There are several histological staining technics being used for the evaluation of the healing of bone and cartilage tissues by identifying the structures of interest. Among them, hematoxylin eosin staining comes forward as the most applied technic. However, it is not suitable to identify each and every important histological structure, and some specific staining technics are necessary to identify such structures like new bone formation areas, mineralized bone areas, glycosaminoglycan aggregates, collagen fiber formation, etc; regarding the aim of the research. In this study, bone and articular cartilage samples were taken and stained with Alcian blue staining, Picro-sirius red staining, Masson-Goldner’s trichrome staining, Movat’s pentachrome staining, von Kossa staining technics to identify different structures in bone and cartilage. The outcomes might help researchers to determine the appropriate staining technics to be used in their studies to fully demonstrate their findings