Selenium induced selenocysteine methyltransferase gene expression and antioxidant enzyme activities in Astragalus chrysochlorus

Astragalus sp. are used in folk medicine because of their biological activities and are known for the ability to accumulate high levels of selenium (Se). The purpose of this study was to explore gene expression of selenocysteine methyltransferase (SMT), responsible for forming MeSeCys, and activities of ascorbate peroxidase (APX), peroxidase (POX), catalase (CAT) and glutathione reductase (GR) enzymes in callus tissues of Astragalus chrysochlorus growing in different Se-containing media. Quantitative real-time polymerase chain reaction assay was done for quantification of SMT gene transcript and it was normalized to actin gene. It was found that transcript level of callus tissues grown at 5.2 μM and 26.4 μM Se-enriched media was lower than that of the control callus. In contrast, a high level of Se (132.3 μM) in the medium caused an approximately 4.26 times higher level of SMT transcript in callus than the control. APX, POX, CAT and GR enzymes were all effected by different Se concentrations. While POX and APX activities were higher then control, CAT and GR activities decreased. These results show that an increase of SMT gene expression led to a rise in APX and POX, but a suppression of CAT and GR enzymes activities in Astragalus chrysochlorus. This suggests that Se could be involved in the antioxidant metabolism in Astragalus chrysochlorus

Yüzeyi Fonksiyonelize Edilmiş Nanoparçacıklar ile Kararlı Nanoakışkan Hazırlanması ve Isıl İletkenlik Değişiminin Belirlenmesi

TÜBİTAK MAG Proje01.04.2019Çok çesitli uygulama alanına sahip olan nanoakıskanlar, ısı transferi sistemlerinde, kullanılanakıskanların ısıl iletkenlik katsayısını arttırmak amacıyla baz akıskanın içerisine, ısıl iletkenligiyüksek nano boyutlarda parçacıklar katılmasıyla üretilirler. Nanoakıskanların hazırlanması,hazırlanan nanoakıskanın ısıl iletkenliginin arttırılması her ne kadar basit görünse de çokkarmasık bir sistemdir. Nanoakıskanların ısıl iletkenliginin artması ve ısı transferiuygulamalarında kullanılabilirligi, hazırlanan nanoakıskanın kararlılıgından, viskozitesinekadar birçok önemli parametre ile baglantılıdır. Isıl iletim katsayısı ne kadar artmıs olursaolsun, kararlı olmayan nanoakıskanların kısa sürede çökmesi ve viskozitesinin baz akıskanagöre fazlaca artıs göstermesi, ısı transferi sistemlerinde basınç düsüsüne, korozyona vetıkanıklıklara neden olmaktadır. Tüm bunlar göz önüne alındıgında, hazırlanannanoakıskanların pratikte kullanımı için bu parametrelerin incelenmesi ve birbiri ile olanbaglantılarının ortaya konulması gerekmektedir. Bu projede kararlı nanoakıskanlarınhazırlanması ve ısıl iletkenliklerinin belirlenmesinin yanı sıra bu parametrelerin birbiri ilebaglantısının aydınlatılması hedeflenmistir.Baz akıskan olarak su, etilen glikol (EG) ve kompresör yagı kullanılan bu projede,nanoparçacık olarak farklı yüzey alanlarına sahip grafen nanoplateletler (GNP) ve tek duvarlıkarbon nanotüpler (SWCNT) kullanılmıstır. Nanoakıskan kararlılıgının saglanması amacıyla,polietilen glikol türevi polihedral oligomerik silseskuokzan (PEG-POSS) nanoakıskanlarda ilkkez yüzey aktif madde olarak bu projede kullanılmıstır. Ayrıca hazırlanan akıskanlarınkararlılıgının artması için pH ayarlaması yapılmıstır. SWCNT içeren su bazlı nanoakıskanlarınhazırlanmasında 50 dk ve 100 dk olmak üzere iki farklı ultrasonikasyon süresi kullanılarak ısıliletkenlige etkisi incelenmistir. Kararlılık degerlendirmesi için UV-Vis Spektrofotometrisi veZeta Potansiyeli ölçümleri yapılmıstır. Bu projede örneklerin santrifüj edilmesi gibi farklıislemler sayesinde nanoparçacık konsantrasyonunun zeta potansiyeline etkisi basarıylaincelenmistir. Isıl iletkenlik ölçümleri 3-omega yöntemiyle gerçeklestirilmistir. Ayrıca farklıyüzey alanlarına sahip nanoparçacıkların kullanılması, farklı konsantrasyonlarda yüzey aktifmadde kullanımı ve farklı baz akıskanlarla çalısılması; bu örneklerin reolojik davranısı, ısıliletkenlik ve yüzey gerilimi ile temas açısı gibi ısı transferi sistemlerinde önem tasıyanözelliklerinin belirlenmesi ve bu özellikleri etkileyen parametrelerin incelenmesi, bu projeyi çokyönlü ve basarılı bir çalısma haline getirmistir.Nanofluids, which have a wide range of applications, are produced by the addition of nanosizedparticles having high thermal conductivity to the base fluid to increase the thermalconductivity of the fluids used in heat transfer systems. Preparing the nanofluids andincreasing the thermal conductivity of the nanofluid are very complex process. The increase ofthermal conductivity of nanofluids and its usage in heat transfer applications are related withmany important parameters from the stability of the nanofluids to their viscosity. No matter howmuch the thermal conductivity is increased, the rapid sedimentation of unstable nanofluids andthe increase in viscosity of nanofluids over that of the base fluid lead to pressure drop,corrosion, and clogging in heat transfer systems. Considering all these, it is necessary toexamine these parameters and to make connections with each other for the practical use ofprepared nanofluids. In this project, it is aimed to prepare stable nanofluids and determine theirthermal conductivity and to clarify the connection of these parameters.Distilled water, ethylene glycol (EG), and compressor oil were used as base fluid. Graphenenanoplatelets (GNP) with different surface areas and single walled carbon nanotubes(SWCNT) were used as nanoparticles. Polyethylene glycol-derived polyhedral oligomericsilsesquioxane (PEG-POSS) was used for the first time in literature, as a surface active agentin nanofluids in order to ensure their stability. In addition, pH value was adjusted to increasethe stability of the nanofluids. In the preparation of water-based nanofluids containing SWCNT,the effect of two different ultrasonication times, 50 min and 100 min, on thermal conductivitywas investigated. UV-Vis Spectrophotometry and Zeta Potential analyses were performed forstability assessment. In this project, the effect of nanoparticle concentration on zeta potentialhas been studied successfully through different processes such as centrifugation and dilutionof samples. Thermal conductivity measurements were carried out by 3ω method. In additionto the usage of different carbon based nanoparticles, various concentrations of surface activeagent, and 3 different base fluids; studying the other factors (e.g. pH, ultrasonication time etc.)affecting the thermal, rheological, and surface properties of nanofluids in heat transfer systemhas made this project a multi-faceted and successful work.Key Words: GNP, SWCNT, nanofluids, 3ω thermal conductivity, viscosity

Perspectives of Young Otolaryngologists on Pediatric ENT and the Future of the Field in Turkey

Objective: The purpose of this study was to examine the current status and the future of pediatric otolaryngology in Turkey by evaluating the opinions of young otolaryngologists on pediatric otolaryngology.Methods: The study included 224 otolaryngology physicians who were senior residents registered with the Turkish Otolaryngology and Head-Neck Surgery Association (TORL-HNS). The physicians were in their last two years of otolaryngology training (154 physicians) or had completed their residency training and were in their first year of otolaryngology practice (70 physicians). They were approached via e-mail and Short Message Service (SMS) in October through December 2019 with a descriptive letter and asked to voluntarily complete an online questionnaire consisting of total 25 questions in five sections.Results: The online questionnaire was sent to 224 physicians, and 109 (49%) participated in the survey. All 109 participants answered all the questions. Overall, 71 participants (65.1%) were in training for residency and 38 (34.9%) were in their first year of expertise. According to their professional interests, the participants listed rhinology (45 participants, 41.3%), head and neck surgery (27 participants, 24.8%), facial plastic surgery (19 participants, 17%), otology-neurotology (16 participants, 14.7%), and laryngology-phoniatry (2 participants, 1.8%) as their first preference for subspecialty. Pediatric otolaryngology was never a first choice among the participants, although four (3.7%) listed pediatric otolaryngology as their second preference.Conclusion: The aim of this study was to shed light on the current and future status of pediatric otolaryngology in Turkey. We believe the establishment of exclusive pediatric otolaryngology clinics under the umbrella of general ear, nose and throat (ENT) clinics and the foundation of officially approved fellowship programs would bring this subspecialty field to its deserved and desired level in our country

Effect of Intraoperative Neuromonitoring on Voice Quality in Total Thyroidectomy

Aim: Thyroid gland surgery has a risk of serious complications. Advancements in technology have led to improvements in complications but significant challenges to preserving voice and airway function still remain. The purpose of this study was to evaluate voice quality following total thyroidectomy under neuromonitoring and effect of intraoperative neuromonitoring (IONM) on identification of the recurrent laryngeal nerve (RLN) and external branch of the superior laryngeal nerve (EBSLN). Methods: A total of 80 patients scheduled for total thyroidectomy between May 2015 and March 2016 were included in the study. All the RLNs and EBSLNs were identified. Voice assessment included preoperative and postoperative fiberoptic laryngoscopy, analysis of Jitter, Shimmer, and fundamental frequency and the Voice Handicap index-10. Results: Eighty patients were included in this study (71 females, nine males). There was no significant difference between mean initial and post-dissection electromyographic amplitudes with RLN and EBSLN stimulation. The rate of postoperative transient RLN palsy per nerve at risk was 4.375% (7/160) and null for permanent RLN palsy (0%, 0/160). Conclusion: Both subjective and objective assessments revealed preservation of voice quality in patients after total thyroidectomy under neuromonitoring. IONM may be used effectively and safely in order to identify the EBSLN during thyroid surgery

Evaluation of bcl-2, bax and c-erbB-2 Levels in Chronic Otitis Patients with or without Cholesteatoma

Objective:The aim of this study was to evaluate bcl-2, bax, and c-erbB-2 expressions in primary and secondary acquired cholesteatoma and to indicate the role of apoptosis and accompanying increased cellular proliferation in the pathogenesis of cholesteatoma.Methods:Samples obtained from the skin of the external ear canal (EEC) of patients operated for chronic otitis media (COM) without cholesteatoma constituted Group 1; samples from the EEC skin of patients in Group 3 operated for COM with cholesteatoma and from the EEC skin of patients in Group 4 constituted Group 2; samples obtained from the cholesteatoma matrix of patients operated for COM with primary acquired cholesteatoma constituted Group 3; and samples obtained from the cholesteatoma matrix of patients operated for COM with secondary acquired cholesteatoma constituted Group 4. The assessment of the positive cell ratio was based on the presence of the following findings and was semiquantitatively classified into four groups: 0, no staining; + cell staining (weak positive staining: 1%–33%); ++ cell staining (moderately positive staining: 34%–66%); and +++ cell staining (strong positive staining: 67%–100%).Results:Comparison of the staining scores of bcl-2, bax, and c-erbB-2 revealed a statistically insignificant difference in the staining of samples obtained from the EEC skin (p>0.05). Decreased bcl-2 expression and increased bax and c-erbB-2 expressions were determined in primary and secondary acquired cholesteatoma epithelium compared with the EEC skin of patients operated for COM with or without cholesteatoma, and the differences were found to be statistically significant (p<0.05).Conclusion:In acquired cholesteatoma epithelium, the finding of decreased bcl-2 expression as well as increased bax and c-erbB-2 expressions compared with the EEC skin is an indicator of the increase in both cellular proliferation and apoptosis

Molecular Survey of the Toxoplasma gondii and Neospora caninum in brain tissue of aborted fetuses of Morkaraman sheep in Muş, Türkiye

Toxoplasma gondii and Neospora caninum are obligate intracellular protozoan parasites that can affect different warm-blooded species worldwide. In this study, it was aimed to detect T. gondii and N. caninum using PCR method in brain tissues of aborted sheep fetuses. Brain specimens were collected from 50 Morkaraman sheep fetuses that had undergone abortion at various stages of pregnancy, within the lambing seasons of 2023 in Muş. Approximately 1 cm³ of brain tissue from the right cerebral hemisphere was excised and subsequently frozen at -20°C for DNA extraction. DNA extraction and PCR amplification were then performed. As a result of this study, 11 (22%) of 50 brain tissues were positive. All brain samples examined in this study were negative for Neospora caninum. Based on the results of this study, it is possible to say that T. gondii is an important abortion agent in sheep in this region. Although N. caninum was not detected in this study, larger scale studies are recommended. Moreover, this study provides important information to breeders and veterinarians in the field in the evaluation and management of abortion

De Novo Transcriptome Assembly and Comparative Analysis Elucidate Complicated Mechanism Regulating Astragalus chrysochlorus Response to Selenium Stimuli

Astragalus species are medicinal plants that are used in the world for years. Some Astragalus species are known for selenium accumulation and tolerance and one of them is Astragalus chrysochlorus, a secondary selenium accumulator. In this study, we employed Illumina deep sequencing technology for the first time to de novo assemble A. chrysochlorus transcriptome and identify the differentially expressed genes after selenate treatment. Totally, 59,656 unigenes were annotated with different databases and 53,960 unigenes were detected in NR database. Transcriptome in A. chrysochlorus is closer to Glycine max than other plant species with 43,1 percentage of similarity. Annotated unigenes were also used for gene ontology enrichment and pathway enrichment analysis. The most significant genes and pathways were ABC transporters, plant pathogen interaction, biosynthesis of secondary metabolites and carbohydrate metabolism. Our results will help to enlighten the selenium accumulation and tolerance mechanisms, respectively in plants

Patterns of active and passive smoking, and associated factors, in the South-east Anatolian Project (SEAP) region in Turkey

BACKGROUND: Smoking is an important health threat in Turkey. This study aimed to determine the frequency of and main factors associated with smoking in persons of 15 years and over, and the frequency of passive smoking in homes in the South-east Anatolian Project (SEAP) Region in Turkey. METHODS: A cross sectional design was employed. The sample waschosen by the State Institute of Statistics using a stratified cluster probability sampling method. 1126 houses representing the SEAP Region were visited. Questionnaires about tobacco smoking and related factors were applied to 2166 women and 1906 men (of 15 years old and above) in their homes. Face-to-face interview methods were employed. Participants were classified as current, ex, and non-smokers. The presence of a regular daily smoker in a house was used as an indication of passive smoking. The chi-square andlogistic regressionanalysis methods were used for the statistical analysis. RESULTS: The prevalence of smoking, in those of 15 years and over, was 11.8% in women and 49.7% in men. The prevalence of current smokers was higher in urban (34.5 %) than in rural (22.8 %) regions. The mean of total cigarette consumption was 6.5 packs/year in women and 17.9 packs/year in men. There was at least one current smoker in 70.1% of the houses. CONCLUSION: Smoking is a serious problem in the South-eastern Anatolian Region. Male gender, middle age, a high level of education and urban residency were most strongly associated with smoking