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31.
This study demonstrates the debilitative effect of a coelomic gregarine, Diplocystis tipulae, on Tipula paludosa. The larvae were provided contaminated fresh grass leaves from a field where 40.0% of T. paludosa larvae were infected by this pathogen. Resultant infected larvae were separated into four groups according to infection level. Analysing their weights, lengths, and weight/length ratios showed that larval size decreased as infection level increased. Differences, especially at the lower and upper levels of the infection levels, were statistically significant. It was concluded that infection by D. tipulae affected the size of T. paludosa larvae resulting in smaller individuals. 相似文献
32.
Mehmet Kahraman Ayse Ozbay Handan Yuksel Ramazan Solmaz Baran Demir Humeyra Caglayan 《Plasmonics (Norwell, Mass.)》2018,13(3):785-795
Surface-enhanced Raman scattering (SERS) is an emerging analytical method used in biological and non-biological structure characterization. Since the nanostructure plasmonic properties is a significant factor for SERS performance, nanostructure fabrication with tunable plasmonic properties are crucial in SERS studies. In this study, a novel method for fabrication of tunable plasmonic silver nanodomes (AgNDs) is presented. The convective-assembly method is preferred for the deposition of latex particles uniformly on a regular glass slide and used as a template for polydimethylsiloxane (PDMS) to prepare nanovoids on a PDMS surface. The obtained nanovoids on the PDMS are used as a mold for AgNDs fabrication. The nanovoids are filled with Ag deposition by the electrochemical method to obtain metallic AgNDs. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) are used for characterization of the structural properties of all fabricated AgNDs. The optical properties of AgNDs are characterized with the evaluation of SERS activity of 4-aminothiphonel and rhodamine 6G. In addition to experimental characterizations, the finite difference time domain (FDTD) method is used for the theoretical plasmonic properties calculation of the AgNDs. The experimental and theoretical results show that the SERS performance of AgNDs is strongly dependent on the heights and diameters of the AgNDs. 相似文献
33.
Bugdaci MS Zuhur SS Sokmen M Toksoy B Bayraktar B Albayrak B Altuntas Y 《Helicobacter》2011,16(2):124-130
Background: Helicobacter pylori infection is a most frequent cause of chronic gastritis. H. pylori may decrease absorption of oral thyroxine by decreasing gastric acid secretion in the stomach. In this study, we aimed to investigate the change in thyroid function tests of the cases after H. pylori eradication who were not responding to high doses of thyroxine treatment before H. pylori eradication. Methods: Hypothyroid cases who were not responding to high doses of thyroxine among the ones presented to Endocrinology and Gastroenterohepatology Clinics of Sisli Etfal Training and Research Hospital between 2009 and 2010 were included in the study. Thyroid function tests were performed two times in all cases before and after H. pylori eradication. Duodenal, antral and corporal biopsies, and jejunal aspirates and biopsies were taken during upper gastrointestinal system endoscopies performed in all patients. Cases without intestinal pathology were included in the study. Results: Serum thyrotropin (TSH), free T3, and free T4 values before H. pylori eradication were 30.5 ± 28.8 IU/mL, 2.64 ± 0.56 pg/mL, and 0.92 ± 0.32 ng/mL, respectively, and after eradication were found to be 4.2 ± 10.6 IU/mL, 3.02 ± 0.61 pg/mL, and 1.3 ± 0.34 ng/mL, respectively (p values <.001, .002, and <.001, respectively). After H. pylori eradication treatment, TSH decreased in all of the cases, factitious thyrotoxicosis developed in % 21 of these cases. Conclusion: In hypothyroid cases, H. pylori gastritis may be responsible for an inadequate response to the treatment. H. pylori eradication in the cases receiving high doses of thyroxine has a risk for thyrotoxicosis. 相似文献
34.
Tascilar ME Ozgen IT Abaci A Serdar M Aykut O 《Biological trace element research》2011,143(1):188-195
The quality of the diet of obese children is poor. Eating habits may alter micronutrient status in obese patients. In this
study, we determined the serum levels of selenium, zinc, vanadium, molybdenum, iron, copper, beryllium, boron, chromium, manganese,
cobalt, silver, barium, aluminum, nickel, cadmium, mercury, and lead in obese Turkish children. Thirty-four obese and 33 healthy
control subjects were enrolled in the study. Serum vanadium and cobalt levels of obese children were significantly lower than
those of the control group (0.244 ± 0.0179 vs. 0.261 ± 0.012 μg/l, p < 0.001, and 0.14 ± 0.13 vs. 0.24 ± 0.15 μg/l, p = 0.011, respectively). There was no significant difference between groups regarding the other serum trace element levels.
In conclusion, there may be alterations in the serum levels of trace elements in obese children and these alterations may
have a role in the pathogenesis of obesity. 相似文献
35.
Mehmet Esref Alkis Hakki Murat Bilgin Veysi Akpolat Korkut Yegin Mehmet Cihan Yavas 《Electromagnetic biology and medicine》2019,38(1):32-47
Ubiquitous and ever increasing use of mobile phones led to the growing concern about the effects of radiofrequency radiation (RFR) emitted by cell phones on biological systems. The aim of this study is to explore whether long-term RFR exposure at different frequencies affects DNA damage and oxidant-antioxidant parameters in the blood and brain tissue of rats. 28 male Sprague Dawley rats were randomly divided into four equal groups (n = 7). They were identified as Group 1: sham-control, Group 2: 900 MHz, Group 3: 1800 MHz, and Group 4: 2100 MHz. Experimental groups of rats were exposed to RFR 2 h/day for 6 months. The sham-control group of rats was subjected to the same experimental condition but generator was turned off. Specific absorption rates (SARs) at brain with 1 g average were calculated as 0.0845 W/kg, 0.04563 W/kg, and 0.03957, at 900 MHz, 1800 MHz, and 2100 MHz, respectively. Additionally, malondialdehyde (MDA), 8-hydroxydeoxyguanosine (8-OHdG), total antioxidant status (TAS), and total oxidant status (TOS) analyses were conducted in the brain tissue samples. Results of the study showed that DNA damage and oxidative stress indicators were found higher in the RFR exposure groups than in the sham-control group. In conclusion, 900-, 1800-, and 2100-MHz RFR emitted from mobile phones may cause oxidative damage, induce increase in lipid peroxidation, and increase oxidative DNA damage formation in the frontal lobe of the rat brain tissues. Furthermore, 2100-MHz RFR may cause formation of DNA single-strand breaks. 相似文献
36.
Mehmet Karaca Burcu Hismi Riza Koksal Ozgul Sefayet Karaca Didem Yucel Yilmaz Turgay Coskun Hatice Serap Sivri Aysegul Tokatli Ali Dursun 《Gene》2014
Classical homocystinuria is the most commonly inherited disorder of sulfur metabolism, caused by the genetic alterations in human cystathionine beta-synthase (CBS) gene. In this study, we present comprehensive clinical findings and the genetic basis of homocystinuria in a cohort of Turkish patients. Excluding some CBS mutations, detailed genotype–phenotype correlation for different CBS mutations has not been established in literature. We aimed to make clinical subgroups according to main clinical symptoms and discussed these data together with mutational analysis results from our patients. Totally, 16 different mutations were identified; twelve of which had already been reported, and four are novel (p.N93Y, p.L251P, p.D281V and c.829−2A>T). The probands were classified into three major groups according to the clinical symptoms caused by these mutations. A psychomotor delay was the most common diagnostic symptom (n = 12, 46.2% neurological presentation), followed by thromboembolic events (n = 6, 23.1% vascular presentation) and lens ectopia, myopia or marfanoid features (n = 5, 19.2% connective tissue presentation). Pyridoxine responsiveness was 7.7%; however, with partial responsive probands, the ratio was 53.9%. 相似文献
37.
Genome-wide fungal stress responsive miRNA expression in wheat 总被引:2,自引:0,他引:2
Behçet Inal Mine Türktaş Hakan Eren Emre Ilhan Sezer Okay Mehmet Atak Mustafa Erayman Turgay Unver 《Planta》2014,240(6):1287-1298
38.
Kilercioglu Serdar Ay Ozcan Oksuz Hale Yilmaz Mehmet Bertan 《Molecular biology reports》2020,47(7):5243-5251
Molecular Biology Reports - Emamectin, a neurotoxic agent, is a semi-synthetic insecticide that belongs to the Avermectin family and is used against helmintic infections in the Salmonidae family.... 相似文献
39.
Effect of EDTA and Tannic Acid on the Removal of Cd,Ni, Pb and Cu from Artificially Contaminated Soil by Althaea rosea Cavan 总被引:1,自引:0,他引:1
Seydahmet Cay Ahmet Uyanik Mehmet Soner Engin Hamdi Guray Kutbay 《International journal of phytoremediation》2015,17(6):568-574
In this study an ornamental plant of Althaea rosea Cavan was investigated for its potential use in the removal of Cd, Ni, Pb and Cu from an artificially contaminated soil. Effect of two different chelating agents on the removal has also been studied by using EDTA (ethylenediaminetetracetic acid) and TA (tannic acid). Both EDTA and TA have led to higher heavy metal concentration in shoots and leaves compared to control plants. However EDTA is generally known as an effective agent in metal solubilisation of soil, in this study, TA was found more effective to induce metal accumulation in Althaea rosea Cavan under the studied conditions. In addition to this, EDTA is toxic to some species and restraining the growth of the plants. The higher BCF (Bio Concentration Factor) and TF (Translocation Factor) values obtained from stems and leaves by the effects of the chemical enhancers (EDTA and TA) show that Althaea rosea Cavan is a hyper accumulator for the studied metals and may be cultivated to clean the contaminated soils. 相似文献
40.
Jafar Rezaie Reza Rahbarghazi Milad Pezeshki Mahdi Mazhar Farshid Yekani Majid Khaksar Elhameh Shokrollahi Hassan Amini Shahriar Hashemzadeh Sadiye Emel Sokullu Mehmet Tokac 《Journal of cellular physiology》2019,234(12):21732-21745
Extracellular vesicles (EVs) are nano-sized vesicles, released from many cell types including cardiac cells, have recently emerged as intercellular communication tools in cell dynamics. EVs are an important mediator of signaling within cells that influencing the functional behavior of the target cells. In heart complex, cardiac cells can easily use EVs to transport bioactive molecules such as proteins, lipids, and RNAs to the regulation of neighboring cell function. Cross-talk between intracardiac cells plays pivotal roles in the heart homeostasis and in adaptive responses of the heart to stress. EVs were released by cardiomyocytes under baseline conditions, but stress condition such as hypoxia intensifies secretome capacity. EVs secreted by cardiac progenitor cells and cardiosphere-derived cells could be pinpointed as important mediators of cardioprotection and cardiogenesis. Furthermore, EVs from many different types of stem cells could potentially exert a therapeutic effect on the damaged heart. Recent evidence shows that cardiac-derived EVs are rich in microRNAs, suggesting a key role in the controlling of cellular processes. EVs harboring exosomes may be clinically useful in cell-free therapy approaches and potentially act as prognosis and diagnosis biomarkers of cardiovascular diseases. 相似文献