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71.
It is well known that neuropeptide Y (NPY) and gamma-aminobutyric acid (GABA) exert antiepileptic effects in animal models. It has recently been shown that ghrelin neurons increase the activities of GABA and NPY in the brain. Therefore it can be said that ghrelin is an antiepileptic agent. In this study we aimed to investigate the antiepileptic effect of ghrelin in an acute experimental epilepsy model in pentylenetetrazole (PTZ) injected rats. Adult male Wistar albino rats were divided into a control group and four experimental groups with seven rats in each group. In order to generate epileptic seizures, PTZ (50mg/kg) was injected intraperitoneally. The experimental groups received intraperitoneal injections of ghrelin at doses of 20, 40, 60 and 80microg/kg 30min before PTZ injection. After PTZ injection, the latencies were separated into three components: first myoclonic jerk, generalized clonic seizures and tonic generalized extension. The injection of 50mg/kg PTZ-induced epileptic seizures in the control group. The onset times of the three characteristic behavioral changes were significantly delayed and the duration of tonic generalized extension was diminished by dose-dependent ghrelin administration. Our results demonstrated that ghrelin suppresses the onset time of PTZ-induced seizures. In the light of our current knowledge, it seems that ghrelin may be considered as an antiepileptic drug. 相似文献
72.
Ercan Varol Selahattin Akcay I. Hakki Ersoy Mehmet Ozaydin Banu Kale Koroglu Simge Varol 《Biological trace element research》2010,133(2):121-127
Sixty-three patients with endemic fluorosis (36 males/27 females; mean age 33.9 ± 8.6 years) and 45 age-, sex-, and body mass index-matched healthy controls (30 males/15 females; mean age 32.7 ± 8.8 years) were included in this study. Aortic stiffness indices, aortic strain (AS), aortic distensibility (AD), and aortic strain index (ASI) were calculated from the aortic diameters measured by echocardiography and blood pressure obtained by sphygmomanometry. The urine fluoride levels of fluorosis patients were significantly higher than control subjects as expected (1.9 ± 0.1 mg/l vs. 0.4 ± 0.1 mg/l, respectively; P < 0.001). AS and AD were significantly lower in fluorosis patients than in the controls (for AS 5.3 ± 3.6 vs. 8.0 ± 3.4%; P < 0.001 and for AD 0.2 ± 0.1 vs. 0.3 ± 0.1 cm2 dyn−1 10−3; P < 0.001, respectively). In contrast, signicantly higher ASI was observed in fluorosis patients than in the controls (3.4 ± 0.6 vs. 3.0 ± 0.4; P < 0.001, respectively). The results of our study demonstrate that elastic properties of ascending aorta are impaired in patients with endemic fluorosis. 相似文献
73.
74.
Ozcan U Ozcan L Yilmaz E Düvel K Sahin M Manning BD Hotamisligil GS 《Molecular cell》2008,29(5):541-551
Mammalian target of rapamycin, mTOR, is a major sensor of nutrient and energy availability in the cell and regulates a variety of cellular processes, including growth, proliferation, and metabolism. Loss of the tuberous sclerosis complex genes (TSC1 or TSC2) leads to constitutive activation of mTOR and downstream signaling elements, resulting in the development of tumors, neurological disorders, and at the cellular level, severe insulin/IGF-1 resistance. Here, we show that loss of TSC1 or TSC2 in cell lines and mouse or human tumors causes endoplasmic reticulum (ER) stress and activates the unfolded protein response (UPR). The resulting ER stress plays a significant role in the mTOR-mediated negative-feedback inhibition of insulin action and increases the vulnerability to apoptosis. These results demonstrate ER stress as a critical component of the pathologies associated with dysregulated mTOR activity and offer the possibility to exploit this mechanism for new therapeutic opportunities. 相似文献
75.
Kalender V Aydm H Karabulut AB Ozcan M Amiraslanov A 《Plastic and reconstructive surgery》2000,106(7):1494-8; discussion 1499-500
Postburn skin contracture of the inframammary sulcus is a commonly encountered problem, especially in pubescent girls. Release of these contractures is commonly performed by split-thickness skin grafts, which necessitate further operations as the child grows. If the contracture of the inframammary sulcus is only one-sided, then the inframammary tissues of the contralateral breast can be used for reconstruction with the fasciocutaneous island flap. The donor site can be closed primarily without disrupting the appearance of the healthy breast, and the skin incision is hidden in the inframammary sulcus. The flap described here is a fasciocutaneous island flap based on the internal mammary artery and the perforating branches to the skin and subcutaneous tissues that the artery gives off as it leaves the thoracic cavity through the seventh intercostal space. After being supported by fresh cadaver and angiographic studies, the flap was applied to seven female patients (four of whom were pubescent) with burn contracture of the breast; satisfactory results were obtained. In defects of the mammary region that required volume or for which repair by skin grafting was planned, in sternal defects, or in young patients, this flap seems to be the best choice. 相似文献
76.
Hakan Erdem Zeliha Kocak-Tufan Omer Yilmaz Zuhal Karakurt Aykut Cilli Hulya Turkan Ozlem Yazicioglu-Mocin Nalan Adıguzel Gokay Gungor Canturk Taşcı Gulden Yilmaz Oral Oncul Aygul Dogan-Celik Ozcan Erdemli Nefise Oztoprak Yakup Tomak Asuman Inan Demet Tok Sibel Temur Hafize Oksuz Ozgur Senturk Unase Buyukkocak Fatma Yilmaz-Karadag Derya Ozturk-Engin Dilek Ozcengiz Ahmet Karakas Hayati Bilgic Hakan Leblebicioglu 《Annals of clinical microbiology and antimicrobials》2014,13(1):1-5
Background
Burkholderia cepacia complex (BCC) bacteria are highly virulent, typically multidrug-resistant, opportunistic pathogens in cystic fibrosis (CF) patients and other immunocompromised individuals. B. vietnamiensis is more often susceptible to aminoglycosides than other BCC species, and strains acquire aminoglycoside resistance during chronic CF infection and under tobramycin and azithromycin exposure in vitro, apparently from gain of antimicrobial efflux as determined through pump inhibition. The aims of the present study were to determine if oxidative stress could also induce aminoglycoside resistance and provide further observations in support of a role for antimicrobial efflux in aminoglycoside resistance in B. vietnamiensis.Findings
Here we identified hydrogen peroxide as an additional aminoglycoside resistance inducing agent in B. vietnamiensis. After antibiotic and hydrogen peroxide exposure, isolates accumulated significantly less [3H] gentamicin than the susceptible isolate from which they were derived. Strains that acquired aminoglycoside resistance during infection and after exposure to tobramycin or azithromycin overexpressed a putative resistance-nodulation-division (RND) transporter gene, amrB. Missense mutations in the repressor of amrB, amrR, were identified in isolates that acquired resistance during infection, and not in those generated in vitro.Conclusions
These data identify oxidative stress as an inducer of aminoglycoside resistance in B. vietnamiensis and further suggest that active efflux via a RND efflux system impairs aminoglycoside accumulation in clinical B. vietnamiensis strains that have acquired aminoglycoside resistance, and in those exposed to tobramycin and azithromycin, but not hydrogen peroxide, in vitro. Furthermore, the repressor AmrR is likely just one regulator of the putative AmrAB-OprM efflux system in B. vietnamiensis. 相似文献77.
Banu Kale Koroglu Ismail Hakki Ersoy Mert Koroglu Ayşe Balkarli Siddika Ersoy Simge Varol Mehmet Numan Tamer 《Biological trace element research》2011,143(1):79-86
Endemic waterborne fluorosis is a public health problem in Isparta, a city located in southern Turkey. Fluoride is a cumulative element that increases metabolic turnover of the bone and also affects the homeostasis of bone mineral metabolism. There are number of similarities between the effects of excess parathyroid hormone (PTH) and fluorosis on bone. So fluoride might show its effect via PTH. We aimed to determine PTH levels in patients with endemic fluorosis to estimate the possible toxic effects of chronic fluoride intake. Fifty-six patients with endemic fluorosis and 28 age-, sex-, and body-mass-index-matched healthy controls were included in this study. Endemic fluorosis was diagnosed according to the clinical diagnosis criteria of Wang. The urine fluoride levels of fluorosis patients were significantly higher than those of control subjects as expected (1.9 ± 0.1 vs. 0.4 ± 0.1 mg/L, respectively; P < 0.001). PTH levels in fluorosis group were significantly higher than control group (65.09 ± 32.91 versus 47.40 ± 20.37, respectively; P = 0.01). The results of our study demonstrate that serum PTH levels are increased in patients with endemic fluorosis. Fluoride, by interfering calcium balance, may be the cause of secondary hyperparathyroidism. 相似文献
78.
Ersoy IH Koroglu BK Varol S Ersoy S Varol E Aylak F Tamer MN 《Biological trace element research》2011,143(2):619-624
Although there are many studies on effect of fluoride on trace elements in experimental animals, few studies exist on serum
trace elements levels in patients with endemic fluorosis. We aimed to determine the serum levels of trace elements including
serum copper (Cu), zinc (Zn), and serum levels of minerals including calcium (Ca), phosphorus (P), magnesium (Mg), sodium
(Na), potassium (K) in patients with endemic fluorosis. The study group consisted of 30 patients with endemic fluorosis (17
females, 13 males, mean age 33.53 ± 9.85 years). An age, gender, and body mass index matched 30 healthy volunteers comprised
control group (21 females, ten males with a mean age 33.93 ± 7.39 years). Urine fluoride levels of chronic fluorosis patients
were significantly higher than that of control subjects as expected (1.92 ± 0.10 mg/l vs. 0.41 ± 0.09 mg/l, respectively;
P < 0.001). Serum Cu levels (89.14 ± 16.77 μg/dL vs. 102.69 ± 25.04 μg/dL, respectively, P = 0.017), serum Zn levels (77.98 ± 20.58 μg/dL vs. 94.57 ± 35.87μg/dL, respectively, P = 0.032), and serum Mg levels (1.92 ± 0.18 mg/dL vs. 2.07 ± 0.31 mg/dL, respectively, p = 0.022) was significantly lower in chronic fluorosis patients than in controls. There were no statistically significant
differences between the fluorosis group and control group with respect to serum levels of Na, K, Ca, and P. We concluded that
chronic fluorosis is associated with reduced serum levels of Cu, Zn, and Mg. 相似文献
79.
A study on age and growth characteristics of spiny gurnard (Lepidotrigla dieuzeidei Blanc & Hureau, 1973), northeastern Mediterranean Sea 下载免费PDF全文
A. Başusta N. Başusta M. Calta E. I. Ozcan 《Zeitschrift fur angewandte Ichthyologie》2017,33(5):966-970
This study investigated the age and growth characteristics of spiny gurnard, Lepidotrigla dieuzeidei, from the northeastern Mediterranean. Samples were collected by commercial trawls during the 2012–2013 fishing seasons. A total 1,878 speciments ranged from 7.10 to 15.90 cm total length and 2.28–35.88 g in weight. Female/male ratio was 1.2/1. The total length–weight relationship was W = 0.002 TL3.579 (r² = .909) for sexes combined, W = 0.0021 TL3.551 (r² = .914) for males and W = 0.0019 TL3.602 (r² = .904) for females. Age determination was conducted using the sagittal otoliths. Ages of examined individulas ranged from 3 to 11 years. Total length‐at‐age data were fitted using the von Bertalanffy growth model. Estimated growth functions were TLt = 18.100 [1?e?0.14 (t + 0.63)] for sexes combined, TLt = 23.587 [1?e?0.08 (t + 1.56)] for males and TLt = 16.612 [1?e?0.19 (t + 0.15)] for females. 相似文献
80.
Sulfites, which are commonly used as preservatives, are continuously formed in the body during the metabolism of sulfur-containing amino acids. Sulfite oxidase (SOX) is an essential enzyme in the pathway of the oxidative degradation of sulfite to sulfate protecting cells from sulfite toxicity. This article investigated the effect of sulfite on total antioxidant capacity (TAC), total oxidant status, lipid hydroperoxide (LOOH), and total free sulfydryl groups (-SH) levels in normal and SOX-deficient male albino rat plasma. For this purpose, rats were divided into four groups: control, sulfite-treated, SOX-deficient, and sulfite-treated SOX-deficient groups. SOX deficiency was established by feeding rats a low molybdenum diet and adding to their drinking water 200 ppm tungsten. Sulfite (70 mg/kg) was administered to the animals via their drinking water. SOX deficiency together with sulfite treatment caused a significant increase in the plasma LOOH and total oxidant status levels. -SH content of rat plasma significantly decreased by both sulfite treatment and SOX deficiency compared to the control. There was also a significant decrease in plasma TAC level by sulfite treatment. In conclusion, sulfite treatment affects the antioxidant/oxidant balance of the plasma cells of the rats toward oxidants in SOX-deficient groups. 相似文献