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101.
Deniz Yamaç Çiğdem Elmas Candan Özoğul Zuhal Keskil Ayşe Dursun 《Ultrastructural pathology》2013,37(1-2):103-110
Endothelium is the first physiological barrier between blood and tissues and can be injured by physical or chemical stress, particularly by the drugs used in the cancer therapy. Paclitaxel and doxorubicin are frequently used anticancer drugs and their cardiac side effects are well observed in clinical setting. Their side effects on the endothelium are still not clear enough. There are few investigations assessing the damages elicited by the combination use of chemotherapy agents in animal experimental models. The purpose of this study was to examine and compare the side effects of doxorubicin and paclitaxel on endothelium in vivo. The drugs were administered weekly to rats via intraperitoneal injections singly or in combinations. Lastly, aorta endothelium was examined. The most familiar parts of the aorta endothelium are the nucleus, free ribosomes, Weibel-Palada granules, plasmalemmal vesicles, and clear basement membrane. Examination of the endothelium and the related structures revealed some clear degenerative findings. Notably, administration of a paclitaxel and doxorubicin combinations caused the most dramatic change in ultrastructure, which may disrupt many functions of the endothelium. 相似文献
102.
103.
Caspar Grond-Ginsbach Tiina M. Metso Antti J. Metso Alessandro Pezzini Turgut Tatlisumak Maani Hakimi Armin J. Grau Manja Kloss Christoph Lichy 《Medical hypotheses》2013
Cervical artery dissection (CeAD) is a frequent cause of stroke among young patients. It is unclear how many CeADs occur asymptomatically or cause subtle and unspecific clinical symptoms. We hypothesize that CeAD remains often unrecognized. Accordingly, the incidence of CeAD might be higher and the stroke risk lower than generally assumed. Lack of CeAD-indicating clinical symptoms is regarded as the main cause of missed diagnoses. We further hypothesize that underrepresentation of asymptomatic and oligosymptomatic patients in CeAD studies may have biased the association between ischemia and local symptoms in CeAD patients as well as the associations of CeAD with risk factors or co-morbidities. We finally hypothesize that symptomatic CeAD may be preceded by an initial asymptomatic phase. According to this final hypothesis, the time of onset of CeAD should be considered uncertain. The issue of unrecognized CeAD is relevant, as it may affect the associations between CeAD and putative risk factors. Furthermore, the existence of clinically silent CeADs may explain why recurrent and familial CeAD have been rarely observed. 相似文献
104.
Satici Begum Gocet-Tekin Emine Deniz M. Engin Satici Seydi Ahmet 《International journal of mental health and addiction》2021,19(6):1980-1988
International Journal of Mental Health and Addiction - The world is currently experiencing a pandemic of an infectious disease called COVID-19 which has drawn global intensive attention. While... 相似文献
105.
Elif Ergun Betül Şimşek Pınar Nercis Koşar Behice Kaniye Yılmaz Ahmet Tuncay Turgut 《Surgical and radiologic anatomy : SRA》2013,35(6):503-509
Purpose
To review the 64-slice CTA (computed tomography angiography) appearance of anatomical variations in branching pattern of the arcus aorta, and to determine their prevalence in 1001 cases.Materials and methods
1001 cases that underwent carotid CTA (performed by a 64-slice scanner) were included in the study.Results
Seven types of aortic arch were found. In 853 cases (853/1001, 85.2 %) classical branching pattern of arcus aorta (three branches; TB, LCC, LS) was observed. Variations were present in 147 cases (147/1001, 14.7 %). One case (1/1001, 0.1 %) had right aortic arch. The most frequent variation was origination of LCC from TB (arch with 2 branches, TB with LCC and LS) which was observed in 78 cases (78/1001, 7.8 %). Origination of LV directly from the aortic arch (four branches; TB, LCC, LV, LS or TB, LCC, LS, LV) was observed in 51 cases (51/1001, 5.1 %). In two cases (2/1001, 0.2 %) truncus bicaroticus (3 branches; RS, common trunk for carotids, LS) was present. In seven cases (7/1001, 0.7 %) aortic arch had four branches in the order of RCC, RS, LCC and LS. In one case (1/1001, 0.1 %) left truncus brachiocephalicus (three branches; RS, RCC, LTB) was present. Seven cases (7/1001, 0.7 %) had aberrant RS (RCC, LCC, LS, RS).Conclusion
Variations in branching pattern of arcus aorta are not rare and being aware of them before surgical and interventional procedures of this region is important. CTA can depict the anatomical features of the aortic arch and is valuable as a road map. 相似文献106.
Guven Yenmis Elif Yaprak Sarac Nail Besli Tugba Soydas Cihan Tastan Derya Dilek Kancagi Muhammet Yilanci Kazim Senol Onur Olgac Karagulle Cumhur Gokhan Ekmekci Ercument Ovali Matem Tuncdemir Turgut Ulutin Gonul Kanigur Sultuybek 《Acta histochemica》2021,123(4):151709
Current evidence strongly suggests that aberrant activation of the nuclear factor kappa B (NF-kB) signaling cascade is connected to carcinogenesis. The matrix metalloproteinases (MMP) which are also the key agents for tumor metastasis may be potent candidates for tumor diagnosis in clinics. In this in vitro study, we hypothesized that metformin with an effective dose can inhibit tumor cell proliferation and metastasis by modulating the expressions of MMP-2 and -9 and interfering with NF-kB signaling in primary breast cancer cells (PBCCs). 300 000 cells per ml were obtained from biopsies of breast tumors from five human donors. The cell viability and proliferation were tested. Immunocytochemistry was performed for MMP-2, MMP-9, and NF-kB, and enzyme-linked immunosorbent assay for NF-kB activity, quantitative real-time PCR for RELA/p65, IkBα, MMP-2, and MMP-9. Three different doses of metformin (5, 10, and 25 mM) (Met) reduced the viability and proliferation of PBCCs in a dose-dependent manner, maximum inhibition was observed at 25 mM Met. The expression of RELA/p65 was not affected by 25 mM Met. Nuclear immunoreactivity and activity of NF-kB reduced while cytoplasmic NF-kB (p65) elevated by 25 mM Met compared to non-treatment (P < 0.05). The expression and immunoreactivity of MMP-9 but not MMP-2 were decreased by 25 mM Met treatment, compared with the non-treatment (P < 0.05). Metformin may have an essential antitumor role in the invasion and metastasis pathways of PBCCs by downregulating the MMP-9 expression blocking both the activity and nuclear translocation of NF-kB. 相似文献
107.
Bayram Ozlem Haskologlu Sule Bayrakoğlu Deniz Bal Sevgi Kostel Islamoglu Candan Cipe Funda Erol Kendirli Tanil Kursun Nazmiye Guner Sukru Nail Yildiran Alisan Bozdogan Gunseli Yuksek Mutlu Reisli Ismail Dalva Klara Aytekin Caner Boztug Kaan Dogu Figen Ikinciogullari Aydan 《Journal of clinical immunology》2021,41(7):1563-1573
Journal of Clinical Immunology - Severe combined immunodeficiency is an inborn error of immunity characterized by impairments in the numbers and functions of T and B lymphocytes due to various... 相似文献
108.
109.
Ozturk Buket Caliskaner Atahan Ersan Gencer Aysegul Harbiyeli Deniz Ongel Karabul Emine Mazıcan Nejdiye Toplutas Kubra Nur Acar Hazal Cansu Sager Sait Gemicioglu Bilun Borekci Sermin 《Annals of nuclear medicine》2021,35(10):1117-1125
Annals of Nuclear Medicine - Pulmonary embolism is a severe source of mortality and morbidity in patients with severe and critical coronavirus disease 2019. It is not yet clear whether the tendency... 相似文献
110.
Mehmet Cihan Cakir Hasan Kocer Yilmaz Durna Deniz Umut Yildirim Amir Ghobadi Hodjat Hajian Koray Aydin Hamza Kurt Necdet Saglam Ekmel Ozbay 《RSC advances》2020,10(50):29945
The phase change behavior of vanadium dioxide (VO2) has been widely explored in a variety of optical and photonic applications. Commonly, its optical parameters have been studied in two extreme regimes: hot (metallic) and cold (insulating) states. However, in the transition temperatures, VO2 acts like an inherent metamaterial with mixed metallic-insulating character. In this range, the portions of metallic and insulating inclusions are tuned by temperature, and therefore a gradual change of optical parameters can be achieved. In this paper, a universal hybrid modeling approach is developed to model VO2 in the intermediate region. For this aim, the measured reflectivity data, is analyzed and matched through the transfer matrix method (TMM) simulations where an effective medium theory (EMT) is employed. Based on the findings of this approach, not only the relative portions of inclusions are tailored but also their grain shapes are significantly altered in the transition range. Finally, the modeling approach is testified by experimental findings through dynamic device applications operating at short and mid infrared wavelengths. In addition, the hysteretic behaviors on electrical, optical, and structural parameters of the VO2 film along the heating and cooling cycles are demonstrated by the experiments and scrutinized by the simulations.A universal hybrid modeling approach is developed to model VO2 in transition, revealing dynamic behavior of metallic inclusions and grain shapes. 相似文献