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41.
Mehmet Çiftçi Metin Bülbül Mustafa Gül Kenan Gümüs¸tekin S¸enol Dane Halis Süleyman 《Journal of enzyme inhibition and medicinal chemistry》2013,28(1):103-109
Effects of nicotine, nicotine+vitamin E and nicotine+Hippophea rhamnoides L. extract (HRe-1) on muscle, heart, lungs, testicle, kidney, stomach, brain and liver carbonic anhydrase (CA; EC 4.2.1.1.) enzyme activities were investigated in vivo. Groups of rats were given nicotine (0.5?mg/kg/day, i.p.), nicotine+vitamin E (75?mg/kg/day, i.g.), nicotine+HRe-1 (250?mg/kg/day, i.g.) and a control group vehicle only. The results showed that nicotine inhibited the heart, lung, stomach and liver CA enzyme activities by ~80% (p?<?0.001), ~94% (p?<?0.001), ~47% (p?<?0.001) and ~81% (p?<?0.001) respectively, and activated muscle and kidney, but had no effects on the testicle and brain CA activities. Nicotine+vitamin E inhibited the heart and liver CA enzyme activities by ~50% (p?<?0.001), and ~50% (p?<?0.001), respectively, and nicotine+vitamin E activated the muscle CA activity. However, nicotine+vitamin E had no effect on lung, testicle, kidney, stomach and brain CA activities. Nicotine+HRe-1 inhibited the heart and stomach CA enzyme activities by ~51% (p?<?0.001), and ~32% (p?<?0.002), respectively, and activated the muscle and brain CA activities, but had no effects on the lung, testicle, kidney, and liver CA activities. In vitro CA inhibition results for similar experiments correlated well with the in vivo experimental results in lungs, testicles, kidney, stomach, brain and liver tissues. 相似文献
42.
Mehmet Ciftci Hayrullah Yilmaz T. Abdulkadir Coban Mustafa Gul Kenan Gumustekin Senol Dane 《Journal of enzyme inhibition and medicinal chemistry》2013,28(2):261-265
The aim of this study was to investigate whether nicotine affects 6-phosphogluconate dehydrogenase (6PGD) enzyme activity in some rat tissues, and to see the modulatory effects of vitamin E on this effect in vivo. In addition, the effects of nicotine and vitamin E on 6PGD activity were also tested in vitro. The groups were: nicotine [0.5 mg/kg/day, intraperitoneal (i.p.)]; nicotine + vitamin E [75 mg/kg/day, intragastric (i.g.)]; and control group (receiving only vehicles). There were eight rats per group and supplementation period was 3 weeks. The results of in vivo study showed that nicotine activated the muscle, lungs, and testicular 6PGD enzyme activity but had no effect on heart and liver 6PGD activity. Also, nicotine + vitamin E activated the muscle, testicle, and liver 6PGD enzyme activity, while this combination had no effect on heart, and lungs in vivo. When nicotine is administered with vitamin E the increase in 6PGD enzyme activity in muscle and testicles were lower. On the other hand the increase in 6PGD enzyme activity was eliminated by vitamin E in lungs, while 6PGD enzyme activity was increased by vitamin E, which was not affected by nicotine only. In vitro results correlated well with in vivo experimental results. Our results suggest that vitamin E may favourably increase 6PGD enzyme activity in liver in nicotine treated rats, while it has negligible effects on this enzyme activity in other tissues. 相似文献
43.
Lourdes Ortiz-Fernández Güher Saruhan-Direskeneli Fatma Alibaz-Oner Sema Kaymaz-Tahra Patrick Coit Xiufang Kong Allan P. Kiprianos Robert T. Maughan Sibel Z. Aydin Kenan Aksu Gokhan Keser Sevil Kamali Murat Inanc Jason Springer Servet Akar Fatos Onen Nurullah Akkoc Nader A. Khalidi Amr H. Sawalha 《American journal of human genetics》2021,108(1):84-99
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45.
Kenan Engin O. Tufan Eroldoğan Ilgın Özşahinoğlu H. Asuman Yılmaz Pınar Mumoğullarında 《Journal of thermal biology》2013
The knowledge about the combined effects of higher temperature and dietary nutrient quality on the diurnal nitrogenous excretion rates is very limited in farmed fish species including European sea bass. Therefore this study investigated the combined effects of increasing levels (30 vs. 60 %) of dietary fish oil replacement by equal mixture of cotton seed oil (CSO) and canola oils (CO) and two different ambient temperature (24 vs. 30 °C) on diurnal total ammonia and Urea–N excretion rates in European sea bass (Dicentrarchus labrax). Experimental diets were fed to fish three times (08:30–13:30–18:30 h) at a fixed rate of 3 % BW.d−1. The daily consumed nitrogen and energy intake of fish were similar during the investigation in different dietary treatments. However, the daily excretion rates of TAN, total nitrogen (TAN+Urea–N) and total nitrogen expressed as a proportion of consumed nitrogen by the European sea bass maintained at 30 °C were found to be significantly (P<0.001) higher (40 to 50%) than fish maintained at 24 °C in all the dietary treatments suggesting higher rates of deamination of ingested amino acids with increased temperature. Daily urea–nitrogen excretion of fish accounted for between 20–30 % of total ammonia–nitrogen excretion rates for each dietary treatment at 24 and 30 °C and appeared to be slightly increased by the temperature but neither the temperature nor the amount of plant oil mixture inclusion in diets or the interaction of these two factors had a significant effect on the urea nitrogen excretion rates of fish in different dietary treatments. However, Urea–N excretion rates in fish fed fish oil only (FO) diet were significantly higher (P<0.05) compared to that of fish fed diets containing increasing amount of plant oil mixture (VOM30 and VOM 60) during the light-on phase of the sampling period at 24 °C indicating periodic enhancement of permeability for urea at excretion sites. Further research is needed in order to elucidate the mechanism of nitrogenous excretion in European sea bass fed plant oil containing diets under extreme summer time temperatures employing total dietary fish oil replacement to reveal the possible effects of alteration in cell membrane phospholipid composition on enzymes responsible for nitrogenous excretion and/or detoxification. 相似文献
46.
The aim of this study was to evaluate the effects of dithioerythritol added to cryopreservation extender on the post-thawed sperm parameters, lipid peroxidation and antioxidant activities of Merino ram sperm. Semen samples from 5 mature Merino rams (1 and 2 years of age) were used in the study. Semen samples, which were diluted with a Tris-based extender containing 0.5, 1, and 2 mM dithiothreitol and no antioxidant (control), were cooled to 5 °C and frozen in 0.25 ml French straws. Frozen straws were then thawed individually at 37 °C for 20 s in a water bath for evaluation.The addition of dithioerythritol at 0.5 and 2 mM doses led to higher percentages of subjective motility (62.9 ± 4.2% and 63.6 ± 1.8%) compared to control (52.0 ± 4.9%, P < 0.05). As regards CASA motility, dithioerythritol 0.25 and 2 mM (60.2 ± 4.5% and 59.6 ± 1.2%) groups were higher from that of control (44.2 ± 8.7%, P < 0.05). For the CASA progressive motility, 0.25, 0.5 and 2 mM doses of dithioerythritol (22.0 ± 2.1%, 21.7 ± 2.5% and 24.0 ± 1.2%) had increasing effect in comparison to control (15.0 ± 2.5%). Dithioerythritol at 1 and 2 mM doses for ALH provided higher values compared to the control (P < 0.001) following the freeze–thawing process. Supplementation with dithiothreitol did not significantly affect the integrities of sperm membrane and acrosome, and mitochondrial activities. No significant differences were observed in biochemical parameters among the groups (P > 0.05). Findings of this study showed that dithioerythritol supplementation in semen extenders, was of greater benefit to sperm motility of frozen–thawed ram sperm. 相似文献
47.
Kenan Omurtag Amber Cooper Arnold Bullock Cathy Naughton Valerie Ratts Randall Odem Susan E. Lanzendorf 《PloS one》2013,8(7)
Objective
Determine whether testicular sperm extractions and pregnancy outcomes are influenced by male and female infertility diagnoses, location of surgical center and time to cryopreservation.Patients
One hundred and thirty men undergoing testicular sperm extraction and 76 couples undergoing 123 in vitro fertilization cycles with testicular sperm.Outcome Measures
Successful sperm recovery defined as 1–2 sperm/0.5 mL by diagnosis including obstructive azoospermia (n = 60), non-obstructive azoospermia (n = 39), cancer (n = 14), paralysis (n = 7) and other (n = 10). Obstructive azoospermia was analyzed as congenital absence of the vas deferens (n = 22), vasectomy or failed vasectomy reversal (n = 37) and “other”(n = 1). Sperm recovery was also evaluated by surgical site including infertility clinic (n = 54), hospital operating room (n = 67) and physician’s office (n = 11). Treatment cycles were evaluated for number of oocytes, fertilization, embryo quality, implantation rate and clinical/ongoing pregnancies as related to male diagnosis, female diagnosis, and use of fresh or cryopreserved testicular sperm.Results
Testicular sperm recovery from azoospermic males with all diagnoses was high (70 to 100%) except non-obstructive azoospermia (31%) and was not influenced by distance from surgical center to laboratory. Following in vitro fertilization, rate of fertilization was significantly lower with non-obstructive azoospermia (43%, p = <0.0001) compared to other male diagnoses (66%, p = <0.0001, 59% p = 0.015). No differences were noted in clinical pregnancy rate by male diagnosis; however, the delivery rate per cycle was significantly higher with obstructive azoospermia (38% p = 0.0371) compared to diagnoses of cancer, paralysis or other (16.7%). Women diagnosed with diminished ovarian reserve had a reduced clinical pregnancy rate (7.4% p = 0.007) compared to those with other diagnoses (44%).Conclusion
Testicular sperm extraction is a safe and effective option regardless of the etiology of the azoospermia. The type of surgical center and/or its distance from the laboratory was not related to success. Men with non-obstructive azoospermia have a lower chance of successful sperm retrieval and fertilization. 相似文献48.
Xie Fei Zhou Xiaoyang Lin Tingting Wang Lulu Liu Chuanhong Luo Xi Luo Lihua Chen Huayu Guo Kenan Wei Hong Wang Yong 《Transgenic research》2020,29(5-6):587-598
Transgenic Research - Precise gene editing of model organisms is required for accurately modeling human diseases and deciphering gene functions. In this study, we used a pair of guide RNAs... 相似文献
49.
The IGF-I splice variant MGF increases progenitor cells in ALS, dystrophic, and normal muscle 总被引:1,自引:0,他引:1
Ates K Yang SY Orrell RW Sinanan AC Simons P Solomon A Beech S Goldspink G Lewis MP 《FEBS letters》2007,581(14):2727-2732
The effects of muscle splice variants of insulin-like growth factor I (IGF-I) on proliferation and differentiation were studied in human primary muscle cell cultures from healthy subjects as well as from muscular dystrophy and ALS patients. Although the initial numbers of mononucleated progenitor cells expressing desmin were lower in diseased muscle, the E domain peptide of IGF-IEc (MGF) significantly increased the numbers of progenitor cells in healthy and diseased muscle. IGF-I significantly enhances myogenic differentiation whereas MGF E peptide blocks this pathway, resulting in an increased progenitor (stem) cell pool and thus potentially facilitating repair and maintenance of this postmitotic tissue. 相似文献
50.