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51.
M. Namik Oztanir Osman Ciftci Aslı Cetin M. Akif Durak Nese Basak Yener Akyuva 《Neurological sciences》2014,35(8):1221-1228
This study investigated the effects of 18β-glycyrrhetinic acid (GA) on neuronal damage in brain tissue caused by global cerebral ischemia/reperfusion (I/R) in C57BL/J6 mice. All subjects (n = 40) were equally divided into four groups: (1) sham-operated (SH), (2) I/R, (3) GA, and (4) GA+I/R. The SH group was used as a control. In the I/R group, the bilateral carotid arteries were clipped for 15 min, and the mice were treated with the vehicle for 10 days. In the GA group, mice were given GA (100 mg/kg) for 10 days following a median incision without carotid occlusion. In the GA+I/R group, the I/R model was applied to the mice exactly as in the I/R group, and they were then treated with the same dose of GA for 10 days. Cerebral I/R significantly induced oxidative stress via an increase in lipid peroxidaitons and a decrease in elements of the antioxidant defense systems. However, GA treatment was protective against the oxidative effects of I/R by inducing significant increases in antioxidant defense systems and a significant decrease of lipid peroxidations. Additionally, cerebral I/R increased the incidence of histopathological damage and apoptosis in brain tissue, but these neurodegenerative effects were eliminated by GA treatment. Therefore, the current study demonstrated that GA treatment effectively prevents oxidative and histological damage in the brain caused by global I/R. In this context, GA may be useful for the attenuation of the negative effects of global cerebral I/R and, in the future, it may be a viable and safe alternative treatment for ischemic stroke in humans. 相似文献
52.
The aim of this study was to determine the effects of hesperidin (HP) on neuronal damage in brain tissue caused by global cerebral ischemia/reperfusion (I/R) in C57BL/J6 mice. For this purpose, a total of 40 mice were divided equally into four groups: (1) sham-operated (SH), (2) global cerebral I/R, (3) HP, and (4) HP+I/R. The SH group was used as a control. In the I/R group, the bilateral carotid arteries were clipped for 15 min, and the mice were treated with vehicle for 10 days. In the HP group, mice were administered HP (100 mg/kg) for 10 days without carotid occlusion. In the HP+I/R group, the I/R model was applied to the mice exactly as in the I/R group, and they were then treated with 100 mg/kg HP for 10 days. Cerebral I/R significantly induced oxidative stress via an increase in lipid peroxidation and a decrease in the components of the antioxidant defense system. Furthermore, cerebral I/R increased the incidence of histopathological damage and apoptosis in brain tissue. HP treatment significantly reversed the oxidative effects of I/R and inhibited the development of neurodegenerative histopathology. Therefore, the current study demonstrates that HP treatment effectively prevents oxidative and histological damage in the brain caused by global I/R. In this context, the beneficial effects of HP are likely a result of its strong antioxidant and free radical-scavenging properties. HP may be an useful treatment to attenuate the negative effects of global cerebral I/R. 相似文献
53.
Mehmet Aksoy Ilker Ince Ali Ahiskalioglu Aysenur Dostbil Mine Celik Mehmet Ibrahim Turan Nihal Cetin Bahadir Suleyman Hamit Hakan Alp Halis Suleyman 《Medical hypotheses》2014
This study investigated whether or not the anesthetic effect of ketamine in rats is dependent on adrenal gland hormones. The study was performed on two main rat groups, intact and adrenalectomized. Rat were divided into subgroups and given appropriate doses of ketamine, metyrapone or metyrosine. Durations of anesthesia in the groups were then recorded. Endogenous catecholamine levels were measured in samples taken from peripheral blood. This experimental results showed that ketamine did not induce anesthesia in intact rats at doses of 15 or 30 mg/kg, and that at 60 mg/kg anesthesia was established for only 11 min. However, ketamine induced significant anesthesia even at a dose of 30 mg/kg in animals in which production of endogenous catecholamine (adrenalin, noradrenalin dopamine) was inhibited with metyrosine at a level of 45–47%. Ketamine at 60 mg/kg in animals in which endogenous catecholamine was inhibited at a level of 45–47% established anesthesia for 47.6 min. However, ketamine at 30 and 60 mg/kg induced longer anesthesia in adrenalectomized rats with higher noradrenalin and dopamine levels but suppressed adrenalin production. Adrenalin plays an important role in the control of duration of ketamine anesthesia, while noradrenalin, dopamine and corticosterone have no such function. If endogenous adrenalin is suppressed, ketamine can even provide sufficient anesthesia at a 2-fold lower dose. This makes it possible for ketamine to be used in lengthy surgical procedures. 相似文献
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Validation of the prolapse quality of life questionnaire (P-QOL) in a Turkish population 总被引:2,自引:0,他引:2
Cam C Sakalli M Ay P Aran T Cam M Karateke A 《European journal of obstetrics, gynecology, and reproductive biology》2007,135(1):132-135
OBJECTIVE: To validate the Turkish translated version of the prolapse quality of life questionnaire (P-QOL). STUDY DESIGN: After establishing the test-retest reliability and internal consistency in a pilot study, 310 patients were enrolled in the study and general and subscale scores of the questionnaires were calculated. All participants underwent the International Continence Society (ICS) prolapse score (POP-Q). RESULTS: One hundred and forty-five (49.7%) women were symptomatic and 147 (50.3%) were asymptomatic. The level of missing data ranged from 0 to 2.2%. For the test-retest reliability, Spearman's rho was from 0.91 to 1.00 for all domains (p<0.001). The severity of P-QOL was strongly correlated with the vaginal examination findings among the symptomatic group (p<0.001). Items correlated with the objective vaginal examination findings. The total and domain scores for P-QOL of symptomatic and asymptomatic women were found to be statistically significant (p<0.001). CONCLUSION: The Turkish translated version of the P-QOL is reliable, consistent and valid instrument for assessing symptom severity, impact on quality of life in women with uterovaginal prolapse. It is easy to understand may be easily administered and self-completed by the women. 相似文献
57.
Dane B Dane C Sivri D Kiray M Cetin A Yayla M 《Acta obstetricia et gynecologica Scandinavica》2007,86(6):666-670
BACKGROUND: This study was planned to evaluate the efficiency of the 11-14 week scan in detecting fetuses with major fetal structural abnormalities. METHODS: Some 1,290 pregnant women were submitted to a routine ultrasound scan between the 11th and 14th week after the detection of the fetal viability. The fetal anatomy was examined transabdominally, and in suspected cases transvaginally. Following the scans, the patients were examined in the second or third trimester of pregnancy. Fetal structural abnormalities classified as major and early onset were noted. Isolated choroid plexus cysts, cardiac defects not requiring treatment, mild ventriculomegaly, and mild renal pelviectasis in second trimester were not included. RESULTS: Twenty-four (1.86%) fetuses with various defects were identified, and 17 of these were diagnosed at the 11-14 week scan. The antenatal ultrasound detection rate of the fetuses with major anomalies was 95%, and 70% were detected in the first-trimester assessment. Four cardiac defects associated with genetic syndromes or requiring operation were included (0.31%) in this series. Two of the fetuses with cardiac defects (50%) had an increased nuchal translucency thickness. In this group, none of the fetuses with karyotype anomalies was born alive. CONCLUSIONS: The first-trimester scan is important in routine antenatal care for early detection of fetal defects, and determination of the fetuses at risk of cardiac anomalies and genetic syndromes. 相似文献
58.
Self-healing is the capability of materials to repair themselves after the damage has occurred, usually through the interaction between molecules or chains. Physical and chemical processes are applied for the preparation of self-healing systems. There are different approaches for these systems, such as heterogeneous systems, shape memory effects, hydrogen bonding or covalent–bond interaction, diffusion, and flow dynamics. Self-healing mechanisms can occur in particular through heat and light exposure or through reconnection without a direct effect. The applications of these systems display an increasing trend in both the R&D and industry sectors. Moreover, self-healing systems and their energy storage applications are currently gaining great importance. This review aims to provide general information on recent developments in self-healing materials and their battery applications given the critical importance of self-healing systems for lithium-ion batteries (LIBs). In the first part of the review, an introduction about self-healing mechanisms and design strategies for self-healing materials is given. Then, selected important healing materials in the literature for the anodes of LIBs are mentioned in the second part. The results and future perspectives are stated in the conclusion section. 相似文献
59.
Serdar Durdagi Timucin Avsar Muge Didem Orhan Muge Serhatli Bertan Koray Balcioglu Hasan Umit Ozturk Alisan Kayabolen Yuksel Cetin Seyma Aydinlik Tugba Bagci-Onder Saban Tekin Hasan Demirci Mustafa Guzel Atilla Akdemir Seyma Calis Lalehan Oktay Ilayda Tolu Yasar Enes Butun Ece Erdemoglu Alpsu Olkan Nurettin Tokay eyma Ik Aysenur Ozcan Elif Acar Sehriban Buyukkilic Yesim Yumak 《Molecular therapy》2022,30(2):963
Small molecule inhibitors have previously been investigated in different studies as possible therapeutics in the treatment of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). In the current drug repurposing study, we identified the leukotriene (D4) receptor antagonist montelukast as a novel agent that simultaneously targets two important drug targets of SARS-CoV-2. We initially demonstrated the dual inhibition profile of montelukast through multiscale molecular modeling studies. Next, we characterized its effect on both targets by different in vitro experiments including the enzyme (main protease) inhibition-based assay, surface plasmon resonance (SPR) spectroscopy, pseudovirus neutralization on HEK293T/hACE2+TMPRSS2, and virus neutralization assay using xCELLigence MP real-time cell analyzer. Our integrated in silico and in vitro results confirmed the dual potential effect of montelukast both on the main protease enzyme inhibition and virus entry into the host cell (spike/ACE2). The virus neutralization assay results showed that SARS-CoV-2 virus activity was delayed with montelukast for 20 h on the infected cells. The rapid use of new small molecules in the pandemic is very important today. Montelukast, whose pharmacokinetic and pharmacodynamic properties are very well characterized and has been widely used in the treatment of asthma since 1998, should urgently be completed in clinical phase studies and, if its effect is proved in clinical phase studies, it should be used against coronavirus disease 2019 (COVID-19). 相似文献