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Phenotypic diversity in <i>NAXE</i> mutations
No full textBackground/Aim NAD(P)HX epimerase (NAXE) gene mutations have been associated with early onset progressive encephalopathy. We present three patients with NAXE gene mutations and different initial manifestations. Cases Patient(P)1 was a 30 month-old boy whose neurological regression started after an infection and progressed, ultimately leading to death one year later. His brain magnetic resonance imaging (MRI) findings were suggesting metabolic stroke. P2, nine year-old sister of P1, had mild developmental delay since birth, seizures after age 5 years and pellagra-like skin lesions. P3 was a 15 year old female presenting multifocal neurological signs progressing over months and leading to respiratory insufficiency. Her initial MRI was normal but inflammatory lesions appeared three months after the onset of symptoms. Laboratory investigations including biochemical, serological and metabolic tests, and brain biopsy were unrevealing. Clinical presentation of P1 and P3 initially suggested autoimmune neurological disease, but no response to immunotherapy was obtained. Two different types of variants c.641T > G; p.Ile214Ser and c.128 C > A, p.Ser43* were detected in NAXE in these patients' two unrelated families. All patients were given mitochondrial cocktail including niacin. Discussion NAXE plays an important role in the electron donors for the mitochondrial respiratory chain. Mutations result in accumulation of toxic metabolites, disruption of energy production, and possibly cell death. P1-3 displayed different ages of onset, different clinical courses and MRI findings unreported previously, suggesting immune-mediated encephalitis and metabolic stroke in P1, and an inflammatory process in P3. NAXE mutations should be considered in progressive central nervous system symptoms
Tracing of Amino Acids Dynamics in Cell Lines Based on <SUP>18</SUP>O Stable Isotope Labeling
No full textMetabolite levels and turnover rates are necessary to understand metabolomic dynamics in a living organism fully. Amino acids can play distinct roles in various cellular processes, and their abnormal levels are associated with pathological conditions, including cancer. Therefore, their levels, especially turnover rates, may provide enormous information about a phenotype. 13C- or 13C,15N-labeled amino acids have also been commonly used to trace amino acid metabolism. This study presented a new methodology based on 18O labeling for amino acids that relied on monitoring mass isotopologues to calculate the turnover rates of amino acids. The method optimization studies were carried over for selective amino acid monitoring. This methodology provides a rapid, robust, and simple GC-MS method for analyzing the fluxes of amino acid metabolism. The developed method was applied to fetal human colon (FHC) and human colon carcinoma (Caco-2) cell lines to determine cancer-induced shifts in the turnover rates of amino acids. These results defined metabolic reprogramming in Caco-2 cells through increased glutamate and serine turnovers and sharply decreased turnovers of aspartate, threonine, and methionine, therefore pointing to some metabolic vulnerabilities in the metabolism of cancerous cells. The simple mechanism of the developed methodology, the availability of affordable 18O-enriched water, and the ease of application can open a new arena in fluxomics analysis
Ziya Yılmaz: Yaşamı ve Siyasal Mücadelesi
No full textZiya Yılmaz’ın tarihi, aslında biraz da Türkiye’nin yakın dönem siyasal hayatının tarihidir. Memleketi Fatsa’dan başladığı yolculukta pek çok tarihselolaya şahitlik etmiş, pek çoğuna da birincil dereceden müdahil olmuş bir devrimcinin öyküsüdür.Bu çalışma; 1950’lerin Türkiye’sini, 27 Mayıs 1960 darbesinden önceki gelişmeleri, 1960’lı yılların başındaki yeni cunta arayışları gibi olay veolguları Ziya Yılmaz’ın penceresinden gözlemlemeyi mümkün kılmanın yanında, 1960’lı yılların ikinci yarısında Fatsa’dan Karadeniz’in neredeysebütününe yayılan Türkiye İşçi Partisi teşkilatının nasıl oluştuğunu, hangi yöntem ve araçlarla devrimci bir atılım gerçekleştirildiğini, sürecinönderlerinden izlemeyi vaat etmektedir.Bununla birlikte, kurucularından olduğu Türkiye Halk Kurtuluş Partisi ve Cephesi’nin, etkileri bugün bile süren eylemlerini ve siyasaldeğerlendirmelerini okuyabileceksiniz:Banka soygunları… Mete Has’ın alıkonulması… İsrail Başkonsolosu Efraim Elrom’un kaçırılması ve öldürülmesi… Mahir Çayan, Ulaş Bardakçı,Cihan Alptekin ve Ömer Ayna’yla Maltepe Cezaevinden firar etmeleri… THKP-C’nin TSK içindeki etkisi ve sempatisi… İdam Cezasına mahkûmolması… gibi sansasyonel süreçlerin öykülerini, doğrudan Ziya Yılmaz’ın anlatımlarından gözlemleyebileceksiniz.Ziya Yılmaz’ın kendi anlatımları üzerinden, kronolojik bir hatta derlenmiş bu kitap, çeşitli siyasal olay ve değerlendirmelerin yanı sıra, Ulaş Bardakçıve Mahir Çayan gibi devrimcilerin insani yönlerini de anımsatıyor, aktarıyor.Ve elbette; Hüseyin Cevahir’i, Ahmet Atasoy’u, Ertan Sarıhan’ı, Çörtük İsmet Öztürk’ü, Nihat Yılmaz’ı, Fikri Sönmez’i ve pek çok değerlidevrimciyi…Fatsa’da bir dağ köyündeki mezar taşında “Devrim için yaşadı, Devrim için savaştı!” yazan Fatsalı Ziya Yılmaz’ı…</p
Novel nonmagnetic abutment designs for facial prostheses: an experimental study
No full textBackground/aim: This in vitro study was undertaken with the aim of evaluating and comparing the retentive forces of novel nonmagnetic abutment designs developed as alternatives to conventional magnetic abutments for facial prostheses. Materials and methods: A plexiglass model was constructed and two extraoral implants were placed in these blocks in a parallel position. Nonmagnetic abutments made of titanium were fabricated and screwed onto the implants. The nonmagnetic systems represent a novel design and include two different abutment designs (type 1 and type 2) with silicone attachments. Retentive force values for the three abutment types of a conventional magnetic system (CMS), the nonmagnetic abutment type 1 system (NMS1), and the nonmagnetic abutment type 2 system (NMS2) were measured at the 0th, 120th, 360th, 720th, and 1440th dislodging cycles using a test machine. Given the data's distribution characteristics, nonparametric tests were used for analysis. The Kruskal-Wallis test was used to evaluate significant differences among groups, followed by Dunn's posthoc test for specific group comparisons. The Friedman test compared the number of dislodging cycles for each group, and the Benjamini-Hochberg adjusted Wilcoxon sign-rank test was used for pairwise comparisons. Results: Both NMS1 and NMS2 exhibited significantly higher retentive forces compared to CMS for the same dislodging cycles (p < 0.01). The NMS1 group showed the highest initial retentive force (9.98 +/- 0.89 N), followed by the NMS2 group (9.65 +/- 0.35 N), but this difference was not statistically significant. Significant differences in retention force values were observed among the three groups across the dislodging cycles (p < 0.001). The lowest retentive force in the last dislodging cycle was observed in the CMS group (3.39 +/- 0.04 N). Additionally, the retention forces decreased in all groups with each increasing dislodging cycle. Conclusion: The two newly developed nonmagnetic systems displayed higher retentive forces compared to the magnetic systems and can be considered viable alternative abutment options for facial prostheses
Theranostic advances and the role of molecular imprinting in disease management
No full textMolecular imprinting has become an effective technology in the realm of diagnosing diseases, providing unparalleled specificity and sensitivity. This method is a promising trend in current medical research. This review examines the utilization of molecularly imprinted polymers (MIPs) in theranostic that integrates diagnostic functionalities for personalized medicine. The present work briefly discusses the fundamental concepts of molecular imprinting and how it has evolved into a versatile platform. Subsequently, the utilization of MIPs in the advancement of biosensors is focused, specifically emphasizing their contribution to the detection and diagnosis of diseases. The therapeutic potential of MIPs, focusing on targeted drug delivery and controlled release systems and the integration of MIPs into theranostic platforms is explored through case studies, showcasing the technology's ability to simultaneously diagnose and treat diseases. Finally, we address the current challenges facing MIPs and discuss future perspectives, emphasizing the potential of this technology to revolutionize the next generation
Microbotanical analyses of dental calculus and caries occurrence at Neolithic Tepecik-Çiftlik, Türkiye: insights into diet and oral health
No full textThe transition to agriculture-based economies and sedentary lifeways during the Neolithic brought significant changes in oral health and diet. Despite the influence of physiological and cultural factors, the frequency of dental pathologies, such as caries and dental calculus, is a common consequence of carbohydrate-rich diets. Caries result from bacterial activity that transforms carbohydrates into lactic acid, leading to the demineralisation of tooth enamel. In contrast, dental calculus can trap and preserve biomolecules and microremains-such as phytoliths and starch grains-making it a valuable resource for investigating past diets and lifeways. Although microbotanical analyses of dental calculus and caries occurrence are common in archaeology, these methods are rarely applied together in the same case study. This paper presents the results of the analyses of microbotanical remains, such as phytoliths and starch grains, retrieved from dental calculus, as well as caries occurrence in 11 individuals from Tepecik-& Ccedil;iftlik, a Neolithic settlement in southwestern Cappadocia, Turkey. Caries prevalence aligns with previous studies highlighting the poor oral health of the Neolithic Tepecik-& Ccedil;iftlik community and suggests a high reliance on carbohydrate-rich diets. Microbotanical remains showed contrasting results, with phytoliths indicating the presence of cereals but an absence of starch grains of cereal origin. This lack of cereal starch grains could point towards the influence of culinary and foodway practices on the preservation and occurrence of microbotanical remains in dental calculus, variables often overlooked in the study of ancient diets. These findings contribute to our understanding of the lifeways and oral health of the Neolithic Tepecik-& Ccedil;iftlik community while drawing attention to how foodways and culinary practices may influence or bias the archaeological record
Re-irradiation in progressive diffuse infiltrative pontine glioma in children and young adults
No full textPurpose This study aims to assess oncological outcomes in children and young adults with diffuse infiltrative pontine glioma (DIPG) who have progressed after initial radiotherapy (RT), with an emphasis on the role of re-irradiation. Methods Data from 33 patients aged 25 years or younger with progressive disease after initial RT were retrospectively analyzed. Results The median age at diagnosis was 8 years (range 4-24 years), and the median initial RT dose was 54 Gy (range 39-54 Gy). The median time between initial RT and progression was 8 months (range 3-40 months). In addition to systemic therapy, 15 patients (46%) received re-irradiation due to progression, with a median dose of 23.4 Gy (range 19.8-36 Gy), while 18 patients (54%) were treated with systemic therapy alone. In patients who received re-irradiation after progression, the 1-year post-progression overall survival (OS) was significantly higher compared to those treated with systemic therapy alone (27% vs. 0%, p = 0.01). Among the 15 re-irradiated patients, 9 out of 12 with available data (75%) showed improvement in neurological symptoms following re-irradiation. No patient exhibited acute or late RT-related >= grade 3 toxicity. Conclusion Palliative re-irradiation in children and young adults with progressive DIPG after initial RT provides an approximately 3-month OS benefit and clinical improvement without significant toxicity and should be considered as a standard-of-care approach
Development of magnetically driven contactless piezoelectric nanogenerators utilizing ZnO nanowires with different shaped top electrodes
No full textIn this research, ZnO nanorod (NR)-based contactless piezoelectric nanogenerators (C-PENGs) with pyramidal and zigzag-shaped top electrodes were fabricated. ZnO NRs with different aspect ratios were grown on a Si (100) wafer, which acts as the bottom electrode. Two different top electrode architectures, zigzag-trenched and pyramidal cavity, were used. Additionally, different work function metallic coatings, platinum and nickel (as a cheaper alternative to noble metals) were applied to the architecturally shaped surfaces to achieve a Schottky contact between the top and bottom electrodes. A magnetic field ranging from 3.5 Oe to 55 Oe with a frequency range between 0.5 and 2 Hz was applied to drive the nanogenerator. The results showed that a maximum output voltage of 75 mV and a maximum power density of 20.7 pW cm-2 were successfully generated. The measurement of output power densities revealed that C-PENGs are a promising candidate for future nanorobotics applications
A Tool for Selecting and Writing Texts for Assessing Reading: Reader- Friendly Informative Text Rubric (ODBIMDEPA)
No full textThis study focuses on the rubrics used for text evaluation, with the aim of introducing the Reader-Friendly Informative Text Rubric (ODBIMDEPA). This rubric, developed and validated through a reliability study, evaluates the reader-friendliness of informative texts used both in educational settings and in exams administered by institutions such as the Ministry of National Education (MoNE), the Assessment, Selection and Placement Center (& Ouml;SYM), and the Yunus Emre Institute (YEE). The study also seeks to share insights gained from the analysis of evaluated texts. To achieve these goals, the document review method was employed, resulting in the creation of two distinct datasets. The first dataset, analyzed during the initial stage of the study, comprised 50 informative texts taken from the 5th, 6th, 7th, and 8th-grade textbooks used in MoNE schools in 2018. The second dataset, analyzed in the subsequent stage, included 37 informative texts selected from the YKS (University Entrance) exams administered by & Ouml;SYM in 2023 and 2024. In the first stage, two independent academic raters scored the texts, while in the second stage, 11 expert raters for 4 subjects, 13 raters for 1 subject assessed them across eight dimensions defined by ODBIMDEPA. In the initial analysis, the weighted kappa coefficient was used to evaluate inter-rater reliability, indicating that the weighted average was acceptable and demonstrating that ODBIMDEPA exhibited significant consistency. In the second stage, the dataset was analyzed using the many-facet Rasch model, revealing a rater reliability of 0.95. This high reliability underscores the robustness of the developed rubric. Based on these findings, ODBIMDEPA provides a reliable framework for quantifying the reader-friendliness of informative texts used in assessments administered by institutions such as MoNE and & Ouml;SYM, as well as those in educational textbooks. The rubric facilitates a quantitative assessment of whether these texts are suitable for use in exams or educational settings, offering insights into text selection and evaluation
