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Karadag Abdullah Ozen Ata Ozkurt Mete Can Cavit Bozgeyik Ibrahim Kabadere Selda Uyar Ruhi 《Molecular biology reports》2021,48(7):5531-5539
Molecular Biology Reports - Herein, we identified miRNA signatures that were able to differentiate malignant prostate cancer from benign prostate hyperplasia and revealed the therapeutic potential... 相似文献
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Osmotic characteristics of mouse spermatozoa in the presence of extenders and sugars 总被引:6,自引:0,他引:6
Successful cryopreservation requires cells to tolerate volume excursions experienced during permeating cryoprotectant equilibration and during cooling and warming. However, prior studies have demonstrated that mouse spermatozoa are extremely sensitive to osmotically induced volume changes. A series of three experiments were conducted 1) to test the efficacy of two commonly used extender media components, egg yolk (EY) and skim milk (SM), in broadening the osmotic tolerance limits (OTL) of ICR and B6C3F1 murine spermatozoa; 2) to determine if the extender components affected sperm plasma membrane permeability coefficients for water and cryoprotective agent (CPA) characteristics; and 3) to test the effects of permeating and nonpermeating CPA on mouse sperm morphology. In experiment 1, sperm samples were added to 150, 225, 300, 450, or 600 mOsm NaCl, EY, SM, sucrose, or choline chloride at 22 degrees C and then returned to isosmotic conditions. In experiment 2, epididymal sperm were preequilibrated in 1 M glycerol (Gly) or 2 M ethylene glycol (EG) prepared in SM extender, abruptly exposed to isosmotic conditions at 22, 15, or 2 degrees C, and the corresponding volume excursions were measured and analyzed. In experiment 3, the effects of permeating CPA (0.3 M EG or dimethyl sulfoxide) or nonpermeating CPA (12% sucrose or 18% raffinose) on sperm morphology (i.e., principle midpiece folding and putative membrane fusion) were evaluated. Experiment 1 showed that spermatozoa from ICR and B6C3F1 mice have effectively broader OTL when exposed to EY or SM extenders. The results of experiment 2 indicated that, for ICR sperm, the activation energy (E(a)) for the hydraulic conductivity (L(p)) was unchanged in SM extender. However, for B6C3F1 sperm, there were significant differences in E(a) of L(p) in the presence of Gly and EG. The result of experiment 3 indicated that permeating CPAs damage sperm membrane integrity, causing a high frequency of head-to-tail or tail-to-tail membrane fusion, whereas this occurrence in the presence of nonpermeating CPA was less than 3%. Finally, the results of experiments 1 and 2 were combined in a mathematical model to predict Gly and EG addition and removal in the presence of SM extender, which would prevent mouse sperm membrane damage. These predictions indicated that, for ICR sperm, both Gly and EG may be added and removed in a single step. However, for B6C3F1 spermatozoa, Gly required a two-step addition while EG only required a single step. For removal from B6C3F1 sperm, Gly required a three-step removal process while EG required a two-step removal. 相似文献
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Fadime Atalay Fehmi Odabasoglu Mesut Halici Ahmet Cakir Elif Cadirci Ali Aslan Ozlem Aydin Berktas Cavit Kazaz 《化学与生物多样性》2015,12(11):1756-1767
Two lichen metabolites, rhizonaldehyde ( 1 ) and rhizonyl alcohol ( 2 ), were isolated from the acetone extract of Lobaria pulmonaria by chromatographic methods, and their chemical structures were determined by UV/VIS, IR, and 1D‐ and 2D‐NMR spectroscopic methods. The gastroprotective and in vivo antioxidant activities of extracts of L. pulmonaria and its metabolites, 1 and 2 , were investigated in indomethacin‐induced ulcer models in rats. The gastric lesions were significantly reduced by acetone, hexane, and CHCl3 extracts, with 75.3–41.5% inhibition. Rhizonyl alcohol ( 2 ) significantly reduced the gastric lesions with an inhibition rate of 84.6–42.8%, whereas rhizonaldehyde ( 1 ) significantly increased the gastric lesions. Antioxidant parameters and myeloperoxidase activities were also evaluated in the gastric tissues of the rats. Indomethacin caused oxidative stress, which resulted in lipid peroxidation in gastric tissues by decreasing the levels of the antioxidants as compared to healthy rat tissues. In contrast to indomethacin, all extracts and rhizonyl alcohol ( 2 ) caused a significant decrease in lipid peroxidation levels and an increase in antioxidant parameters, superoxide dismutase, glutathione peroxidase, and glutathione‐S‐transferase, and reduced glutathione in gastric tissues. The administration of rhizonyl alcohol ( 2 ) also resulted in a decrease in gastric myeloperoxidase activity increased by indomethacin. The gastroprotective effect of rhizonyl alcohol ( 2 ) can be attributed to its antioxidant properties and its suppressing effect on neutrophil infiltration into gastric tissues. 相似文献
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The stereochemistry of the addition of methylmagnesium bromide to a steroidal 4,5-epoxy-3-ketone has been shown to be determined by the stereochemistry of the epoxide. The epoxidation to the corresponding 3-alkyl-3-hydroxy-4-enes by per-acid was determined by the stereochemistry of the allylic alcohol. 相似文献
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Spindler RE Crichton EG Agca Y Loskutoff N Critser J Gardner DK Wildt DE 《Theriogenology》2006,66(1):82-92
Domestic cat embryos of excellent quality appear to improve development of conspecific embryos when cultured together, providing an avenue for improving development of embryos from valuable species or individuals. To have relevance to rare species, it would be useful to understand if this advantage could be conferred by heterospecific companions because there usually are severely limited numbers of conspecific embryos available from wildlife donors. In the first study, we incubated single test cat embryos alone (controls) or with 10 cat embryos or 10 or 20 mouse embryos under similar regimented conditions (each group shared 20 microl medium). In the second study, single test cat embryos were cultured alone, with 10 conspecific or 20 mouse embryos or 10 cattle embryos (each group shared 20 microl medium). Single test embryos in all treatment groups achieved similar (P>0.05) stages of compaction and blastocyst development. In the first study, only the test embryos incubated with 10 cat or 20 mouse companion embryos achieved blastocyst expansion. The average total cell number within test embryos incubated with 10 cat or 20 mouse companions was greater (P<0.05) than controls or those placed with 10 mouse embryos. In the second study, test embryos in all groups achieved blastocyst expansion and had more (P<0.05) total cells per embryo than the solitary controls. Inner cell mass to trophoblast cell ratio did not differ among treatments in either study. Thus, companion mouse and cattle embryos selected for excellent quality confer a benefit to singleton cat embryos, although the number of companions necessary to grant an advantage may be species dependent. If this phenomenon can be extrapolated across species, this may be an avenue for 'common animal embryos' to improve developmental potential of embryos from rare, unrelated taxa. 相似文献
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Insecticidal Metabolites from the Rhizomes of Veratrum album against Adults of Colorado Potato Beetle,Leptinotarsa decemlineata
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Tuba Aydin Ahmet Cakir Cavit Kazaz Neslihan Bayrak Yasin Bayir Yavuz Taşkesenligil 《化学与生物多样性》2014,11(8):1192-1204
The dried rhizomes of Veratrum album were individually extracted with CHCl3, acetone, and NH4OH/benzene to test the toxic effects against the Colorado potato beetle, Leptinotarsa decemlineata, which is an important agricultural pest. Fifteen compounds in various amounts were isolated from the extracts using column and thin‐layer chromatography. The chemical structures of 14 compounds were characterized as octacosan‐1‐ol ( 1 ), β‐sitosterol ( 2 ), stearic acid ( 3 ), diosgenin ( 4 ), resveratrol ( 5 ), wittifuran X ( 6 ), oxyresveratrol ( 7 ), β‐sitosterol 3‐O‐β‐D ‐glucopyranoside ( 8 ), diosgenin 3‐O‐α‐L ‐rhamnopyranosyl‐(1→2)‐β‐D ‐glucopyronoside ( 9 ), oxyresveratrol 3‐O‐β‐D ‐glucopyranoside ( 10 ), jervine ( 11 ), pseudojervine ( 13 ), 5,6‐dihydro‐1‐hydroxyjervine ( 14 ), and saccharose ( 15 ) using UV, IR, MS, 1H‐ and 13C‐NMR, and 2D‐NMR spectroscopic methods. However, the chemical structure of 12 , an oligosaccharide, has not fully been elucidated. Compounds 4, 6, 9 , and 10 were isolated from V. album rhizomes for the first time in the current study. The toxic effects of three extracts (acetone, CHCl3, and NH4OH/benzene) and six metabolites, 2, 2 + 4, 5, 7, 8 , and 11 , were evaluated against the Colorado potato beetle. The assay revealed that all three extracts, and compounds 7, 8 , and 11 exhibited potent toxic effects against this pest. This is the first report on the evaluation of the toxic effects of the extracts and secondary metabolites of V. album rhizomes against L. decemlineata. Based on these results, it can be concluded that the extracts can be used as natural insecticides. 相似文献
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