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Background. In transfusion-dependent forms of β-thalassemia, chronic anemia and iron overload lead to the development of oxidative stress-related DNA damage. In β-thalassemia minor (β-Tm), oxidative stress resulting from an unbalanced globin chain ratio has been documented, even in the absence of anemia and its complications. However, the status of oxidative stress-related DNA damage has not yet been elucidated. The aim of this study was to assess DNA damage in β-Tm in a pediatric population. Material and Methods. We compared 142 children with β-Tm to 113 healthy controls, including siblings of the β-Tm individuals. The comet assay was used to assess DNA damage in peripheral blood lymphocytes. Additionally, oxidative stress markers and biochemical parameters were measured. Results. No significant differences were observed between the β-Tm group and controls in terms of demographics, biochemical parameters, or baseline oxidative stress levels (p>0.05). In the comet assay, there was no difference in tail intensity (TI) between subjects and controls, nor between siblings with and without β-Tm (p=0.551 and p=0.655, respectively). However, when the β-Tm group was divided by age, a gradual increase in DNA damage, as measured by TI, was observed. This increase was more pronounced in the β-Tm group compared to controls. Conclusion. We observed no significant differences in DNA damage between β-Tm individuals and controls. However, TI increased at a faster rate with age in carriers compared to non-carriers, suggesting that environmental factors might exert a more pronounced influence on the genetic integrity of individuals with a β-Tm background. Although β-Tm itself does not seem to pose a substantial genotoxic risk in childhood, our findings underscore the importance of further research into the interplay between β-Tm and other risk factors throughout life. We advocate for long-term monitoring of β-Tm children to assess the health and potential genetic consequences.

Background/aim: Dexmedetomidine (DEX) is an alpha-2 adrenergic agonist that is commonly used as a sedative and anesthetic. The protective effects of DEX against oxidative damage under both in vitro and in vivo conditions have been demonstrated. It was aimed to evaluate and compare the protective effects of DEX and vitamin C (Vit C) on DNA against H2O2-induced DNA damage in human lymphocyte cell cultures in vitro by alkaline Comet assay. Materials and methods: Lymphocyte cell cultures were divided into 5 groups, as the negative control, solvent control, positive control, hydrogen peroxide (H2O2; 150 mu M) + DEX (1 mu M; 2.5 mu M; 5 mu M), and H2O2 (150 mu M) Vit C (1 mu M; 2.5 mu M; 5 mu M), and incubated at 37 degrees C for 1 h. Cell viability was measured using the Trypan blue test. DNA damage was measured using the Alkali Comet Technique and the % percent tail intensity was evaluated. Statistical analysis was performed using 1-way ANOVA and the Tukey multiple comparison test. Results: It was observed that H2O2 significantly induced DNA damage in the lymphocytes and this damage was decreased significantly with Vit C and DEX. It was observed that Vit C at doses of 1 mu M and 2.5 mu M had a significantly stronger antioxidant effect, but there was no significant difference between the antioxidant effects of Vit C and DEX with a dose of 5 mu M. The dose of 5 mu M DEX was found to be the most effective in reducing oxidative DNA damage. Conclusion: There is limited data on the protective effects of DEX against oxidative DNA damage. The primary effect might be cytoprotection. The results herein showed that DEX was protective against H2O2-induced in vitro oxidative DNA damage in lymphocyte cell cultures in a dose-dependent manner. DEX might have a potential therapeutic value in the prevention of oxidative DNA damage in patients.

Although various organizations working in developed countries established the standards and approaches used in occupational hygiene, occupational hygiene professional interests and needs continue to develop in a global context. There is thus an urgent need for expanded occupational hygiene models. For successful field implementation, these models should be based on several sets of criteria, including those related to international standards, various national requirements, and multidisciplinary approaches. This is particularly important for countries in which no occupational hygiene model has been developed. This study thus examined the consensus on occupational hygiene standards among stakeholders in Turkey regarding the development of a national model. A modified Delphi study was conducted among key occupational health experts in Turkey who could aid in the relevant implementation, policy-making, and educational processes for such a model. Participants were selected from various governmental institutions, non-governmental organizations, trade unions, universities, and occupational health practices. The first-round findings were obtained from open-ended questions. The results revealed several requirements, including the adoption of an international hygiene definition, the official recognition of professional and practical areas in Turkish occupational hygiene, hygienist training methods, priorities, and competent institutions. Second-round findings indicated a consensus rate of over 80% regarding the need for implementation standards, training and education standards, requirements and priorities, and competent institutions for professionals working in the field of occupational hygiene. A third-round and SWOT analysis was also conducted among the group to confirm the consensus issues. The search for solutions and developmental expectations increases when awareness of internationalization and the need for common global standards increase. This developmental process may provide the basis for an appropriate model in developing countries.

Carbon nanotubes (CNTs) are nanoscale tube-shaped carbon materials used in many industrial areas. Their fiber shape has caused concerns about their toxicity given its structural similarity with asbestos. The aim here was to elucidate the effect of CNTs and asbestos exposure on global DNA and RNA methylation and the methylation of genes associated with cell cycle, inflammation and DNA damage processes in human lung cells. Human bronchial epithelial cells (16HBE14o-) were exposed for 24 h to 25 and 100 µg/ml CNTs (single-walled CNTs [SWCNTs] and multi-walled CNTs [MWCNTs]) and 2.5 µg/ml asbestos (chrysotile, amosite, crocidolite). Global DNA and RNA (hydroxy)methylation to cytosines was measured by a validated liquid chromatography tandem-mass spectrometry method. Global RNA methylation to adenines was measured by a colorimetric ELISA-like assay. Gene-specific DNA methylation status at certain cytosine-phosphate-guanine (CpG) sites of cyclin-dependent kinase inhibitor 1A (CDKN1A), serine/threonine kinase (ATM), and TNF receptor-associated factor 2 (TRAF2) were analyzed by using bisulfite pyrosequencing technology. Only MWCNT-exposed cells showed significant global DNA hypomethylation of cytosine and global RNA hypomethylation of adenosine. SWCNT, MWCNT, and amosite exposure decreased DNA methylation of CDKN1A. ATM methylation was affected by chrysotile, SWCNT and MWCNT. However, SWCNT exposure led to DNA hypermethylation of TRAF2. These findings contribute to further understanding the effect of CNTs on different carcinogenic pathways.

Cholinergic therapy based on cholinesterase (ChE) inhibitory drugs is the mainstay for the treatment of Alzheimer's disease. Therefore, an extensive research has been continuing for the discovery of drug candidates as inhibitors of acetyl‐ and butyrylcholinesterase. In this study, two natural molecules, e. g. hyperforin and hyuganin C were tested in vitro for their AChE and BChE inhibitory activity. Both of the compounds were ineffective against AChE, whereas hyperforin (IC₅₀=141.60±3.39 μm) and hyuganin C (IC₅₀=38.86±1.69 μm) were found to be the highly active inhibitors of BChE as compared to galantamine (IC₅₀=46.58±0.91 μm) which was used as the reference. Then, these molecules were further proceeded to molecular docking experiments in order to establish their interactions at the active site of BChE. The molecular docking results indicated that both of them are able to block the access to key residues in the catalytic triad of the enzyme, while they complement some of the hydrophobic residues of the cavity, what is consistent with our in vitro data. While both compounds were predicted as mutagenic, only hyuganin C showed hepatotoxicity in in silico analysis. According to whole outcomes that we obtained, particularly hyuganin C besides hyperforin are the promising BChE inhibitors, which can be the promising compounds for AD therapy.

Among the plant secondary metabolites much attention has been given to naturally occurring phenolic compounds as attractive candidates for cancer treatment and prevention. Fumana procumbens (Dunal) Gren. & Godr (Cistaceae) is a perennial herb, distributed in inner and southwest Anatolia, Turkey. F. procumbens was shown to be rich in phenolic constituents especially flavonoids and biflavonoids which are known for their antioxidant and anticarcinogenic effects. Thus, this study aims to investigate the anticancer activity of F. procumbens extracts, fractions and pure compounds by MTT test against HeLa, MCF-7, and A549 as well as BEAS-2B cell lines for determining selectivity. Bioactivity-guided phytochemical investigation on Fumana procumbens (Dunal) Gren. & Godr. led to the isolation and identification of three biflavonoids: genkwanol A, dihydrodaphnodorin B and stelleranol. The structures were elucidated by extensive 1D- and 2D-NMR spectroscopic analysis in combination with MS experiments. This is the first report on the isolation of genkwanol A and stelleranol from the genus Fumana and from the family Cistaceae. As a result, no individual cytotoxic activity was obtained for biflavonoid compounds. However, the former fractions FrC and FrD as well as MeOH and n-BuOH extracts exerted moderate and significant cytotoxic activity which suggested a possible synergistic effect.

Perfluoroalkyl and polyfluoroalkyl substances (PFAS) are synthetic chemicals that have been used in industry and consumer products. Because the presence of PFAS has been identified in humans and the environment in the last decade, human exposure to PFAS is a current public health concern. It has been shown that some PFAS lead to adverse health effects in the male reproductive system. However, there is no information about probable genotoxic effects of these chemicals on sperm cells. This study aimed to investigate the possible genotoxic damage on human sperm cells exposed to certain major PFAS compounds that were selected considering their extensive usage, high persistence in the environment, and high bioaccumulation in humans. These PFAS are perfluorooctanesulfonic acid (PFOS), perfluorooctanoic acid (PFOA), perfluorononanoic acid (PFNA), and perfluorohexanoic acid (PFHxA). The alkaline comet assay was used to detect the DNA damage to sperm. Sperm cells were treated with 0.1–1 mM of each PFAS at 32°C for 1 h to obtain optimal survival. As a result of the experiments, it was discovered that the exposure to PFOS, PFOA, PFNA, and PFHxA did not cause significant levels of cytotoxicity and did not cause damage to sperm DNA under these conditions. The results suggest that the exposure to these PFAS did not interfere with sperm DNA. Indirect toxicity mechanisms should be taken into account to assess the association between the PFAS exposure and male reproductive toxicity.

Laboratuvarlar iş yeri olarak çok tehlikeli/tehlikeli olarak sınıflandırılmaktadır. Amaç: Bu tanımlayıcı araştırmanın amacı, T.C. Sağlık Bakanlığı Türkiye İlaç ve Tıbbi Cihaz Kurumu laboratuvarlarında çalışan analist ve teknisyenlerin laboratuvar güvenliği hakkında bazı bilgi ve uygulamalarının belirlenmesidir. Yöntem: Çalışanların (n= 109) %85.0’ine (n=93) ulaşılmıştır. Önceden denenmiş, laboratuvar güvenliğine ilişkin, kendi kendine uygulanabilen bir anket gözlem altında gerçekleştirilmiştir. Bulgular: Katılımcıların çoğunluğu (%66,7) kadındır; laboratuvar tecrübeleri ortalama 12.8±8.2 yıldır ve haftada ortalama 24.6±10.3 saat laboratuvarda çalışmaktadırlar. Çalışanların %53.8’i çalışmaları sırasında genellikle yanıcı/patlayıcı maddelerle, %29.0’u çok/akut toksik veya karsinojenik kimyasallarla, %30.1’i ise fiziksel tehlikelerle çalışmaktadır. Tüm katılımcıların %14.0’ü hiç laboratuvar güvenliği eğitimi almamıştır. Çalışanların “her zaman” önlük, eldiven ve koruyucu gözlük kullanma sıklığı sırasıyla %84.9, %66.7 ve %6.5’tir. Katılımcıların %11.9’u çalışma hayatı boyunca en az bir ciddi büyük yaralanma, %24.7’si ise son altı ay içinde en az bir küçük yaralanma geçirmiştir. Yaşanmış yaralanmalar içinde dikiş gerektirmeyen kesik, ısırık, yırtık (%21.0) ve kimyasal madde buharı soluma (%16.1) ilk sıralardadır. Temel laboratuvar güvenliği bilgisi sorularına doğru cevap verme ortalamaları 100 üzerinden 65.4±26.5’tir. Sonuç: Sonuç olarak, çalışanların güvenlik uygulamalarında yetersiz kaldıkları ve laboratuvar güvenliği hakkında düzenli eğitim almaya istekli oldukları saptanmıştır. Bu konuda iş yeri tarafından düzenli aralıklarla güvenlik konusunda eğitim verilmesi uygun olacaktır.