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1.
Although cryopreservation has been developed and optimized over the past decades, it causes various stresses, including cold shock, osmotic stress, and ice crystal formation, thereby reducing fertility. During cryopreservation, addition of cryoprotective agent (CPA) is crucial for protecting spermatozoa from freezing damage. However, the intrinsic toxicity and osmotic stress induced by CPA cause damage to spermatozoa. To identify the effects of CPA addition during cryopreservation, we assessed the motility (%), motion kinematics, capacitation status, and viability of epididymal spermatozoa using computer-assisted sperm analysis and Hoechst 33258/chlortetracycline fluorescence staining. Moreover, the effects of CPA addition were also demonstrated at the proteome level using two-dimensional electrophoresis. Our results demonstrated that CPA addition significantly reduced sperm motility (%), curvilinear velocity, viability (%), and non-capacitated spermatozoa, whereas straightness and acrosome-reacted spermatozoa increased significantly (p < 0.05). Ten proteins were differentially expressed (two decreased and eight increased) (>3 fold, p < 0.05) after CPA, whereas NADH dehydrogenase flavoprotein 2, f-actin-capping protein subunit beta, superoxide dismutase 2, and outer dense fiber protein 2 were associated with several important signaling pathways (p < 0.05). The present study provides a mechanistic basis for specific cryostresses and potential markers of CPA-induced stress. Therefore, these might provide information about the development of safe biomaterials for cryopreservation and basic ground for sperm cryopreservation. 相似文献
2.
Jin-Ying Cui Han Miao Li-Hong Ding Todd C. Wehner Pan-Na Liu Ye Wang Sheng-Ping Zhang Xing-Fang Gu 《PloS one》2016,11(2)
Spines or trichomes on the fruit of cucumbers enhance their commercial value in China. In addition, glabrous mutants exhibit resistance to aphids and therefore their use by growers can reduce pesticide residues. Previous studies have reported two glabrous mutant plants containing the genes, csgl1 and csgl2. In the present study, a new glabrous mutant, NCG157, was identified showing a gene interaction effect with csgl1 and csgl2. This mutant showed the glabrous character on stems, leaves, tendrils, receptacles and ovaries, and there were no spines or tumors on the fruit surface. Inheritance analysis showed that a single recessive gene, named csgl3, determined the glabrous trait. An F2 population derived from the cross of two inbred lines 9930 (a fresh market type from Northern China that exhibits trichomes) and NCG157 (an American processing type with glabrous surfaces) was used for genetic mapping of the csgl3 gene. By combining bulked segregant analysis (BAS) with molecular markers, 18 markers, including two simple sequence repeats (SSR), nine insertion deletions (InDel) and seven derived cleaved amplified polymorphism sequences (dCAPs), were identified to link to the csgl3 gene. All of the linked markers were used as anchor loci to locate the csgl3 gene on cucumber chromosome 6. The csgl3 gene was mapped between the dCAPs markers dCAPs-21 and dCAPs-19, at genetic distances of 0.05 cM and 0.15 cM, respectively. The physical distance of this region was 19.6 kb. Three markers, InDel-19, dCAPs-2 and dCAPs-11, co-segregated with csgl3. There were two candidate genes in the region, Csa6M514860 and Csa6M514870. Quantitative real-time PCR showed that the expression of Csa6M514870 was higher in the tissues of 9930 than that of NCG157, and this was consistent with their phenotypic characters. Csa6M514870 is therefore postulated to be the candidate gene for the development of trichomes in cucumber. This study will facilitate marker-assisted selection (MAS) of the smooth plant trait in cucumber breeding and provide for future cloning of csgl3. 相似文献
3.
Effect of capsulectomy on the hemodynamics and viability of random-pattern skin flaps raised on expanded skin in the pig 总被引:2,自引:0,他引:2
S F Morris C Y Pang J Mahoney N Lofchy I L Kaddoura R Patterson F Lista 《Plastic and reconstructive surgery》1989,84(2):314-22; discussion 323-4
Skin flaps constructed on expanded skin usually include the underlying capsular tissue. It has been hypothesized that capsulectomy may jeopardize the viability of the expanded skin flap. The experiments reported herein were designed to test this hypothesis. Specifically, we studied the hemodynamics and viability of random-pattern skin flaps (8 X 20 cm) raised on delayed bipedicle flaps (group A) and on expanded skin pockets with capsulectomy at the time of flap elevation (group B) or with intact underlying capsular tissue (group C). Each group was randomly assigned to each flank in 16 pigs. Skin pockets were expanded by inflation of subcutaneous silicone tissue expanders with sterile saline (299 +/- 7 ml; X +/- SEM) over a period of 3 weeks. At the end of this period, the bipedicle flaps were constructed. Eight days later, random-pattern skin flaps were raised on bipedicle flaps and skin pockets. The length and area of skin flap viability, judged by the fluorescein dye test performed 1 day postoperatively, were not significantly different (p greater than 0.05) among groups A, B, and C (n = 31 to 32). There also were no significant differences (p greater than 0.05) in total skin capillary blood flow measured 1 day postoperatively (A = 2.6 +/- 0.4, B = 2.4 +/- 0.4, and C = 2.7 +/- 0.6 ml/min per flap; n = 15 to 16) and in skin viability assessed 7 days postoperatively (A = 74 +/- 2, B = 75 +/- 2, and C = 76 +/- 2 percent; n = 16) among delayed skin flaps and skin flaps raised on expanded skin pockets with or without capsulectomy. The results of this flap viability study were confirmed in 5 minipigs in a separate experiment. We conclude that capsulectomy did not have a detrimental effect on the hemodynamics and viability of random-pattern skin flaps raised on expanded skin. Furthermore, we hypothesize that skin flaps raised on expanded skin are similar to delayed skin flaps in that the skin blood flow is optimally augmented; therefore, the capsular tissue does not add significant blood supply to the overlying skin. 相似文献
4.
Propranolol antagonizes hypotension induced by alpha-blockers but not by sodium nitroprusside or methacholine 总被引:1,自引:0,他引:1
A pressor response has been observed with propranolol, a nonselective beta-adrenoceptor antagonist, in animals given a nonselective alpha-adrenoceptor antagonist. This study investigates whether a pressor response to propranolol occurs in conscious unrestrained rats following a hypotensive response induced by phentolamine (nonselective alpha-antagonist), prazosin (selective alpha 1-antagonist) and (or) rauwolscine (selective alpha 2-antagonist), sodium nitroprusside (smooth muscle relaxant), or methacholine (muscarinic agonist). The rats were subjected to a continuous infusion of a hypotensive agent or normal saline followed by i.v. injection of propranolol. The infusion of phentolamine significantly decreased mean arterial pressure (MAP). Subsequent injection of propranolol restored MAP to the control level. Prazosin and rauwolscine each caused a small but not significant decrease in MAP which was reversed by propranolol. Concurrent infusions of prazosin and rauwolscine caused a significant decrease in MAP. Subsequent injection of propranolol caused a large pressor response which increased MAP to 20% above control MAP prior to the administration of drugs. Nitroprusside or methacholine each caused a significant decrease in MAP, but the hypotension was not antagonized by propranolol. The concurrent infusions of a low dose of nitroprusside and prazosin caused a significant decrease in MAP which was reversed by propranolol. The infusion of saline did not alter MAP, and propranolol did not cause a pressor response. It is concluded that propranolol antagonizes the hypotensive effect of an alpha-blocker but not that of sodium nitroprusside or methacholine. Our results suggest the presence of a specific interaction between alpha- and beta-antagonists. 相似文献
5.
6.
7.
Inka Brockhausen Arthur A Grey Henrianna Pang Harry Schachter Jeremy P Carver 《Glycoconjugate journal》1988,5(4):419-448
Sixteen asparagine-linked oligosaccharides ranging in size from (Man)2(GlcNAc)2 (Fuc)1 to (GlcNAc)6(Man)3(GlcNAc)2 were obtained from human 1-acid glycoprotein and fibrinogen, hen ovomucoid and ovalbumin, and bovine fetuin, fibrin and thyroglobulin by hydrazinolysis, mild acid hydrolysis and glycosidase treatment. The oligosaccharides hadN-acetylglucosamine at the reducing termini and mannose andN-acetylglucosamine residues at the non-reducing termini and were prepared for use asN-acetylglucosaminyltransferase substrates. Purification of the oligosaccharides involved gel filtration and high performance liquid chromatography on reverse phase and amine-bonded silica columns. Structures were determined by 360 MHz and 500 MHz proton nuclear magnetic resonance spectroscopy, fast atom bombardment-mass spectrometry and methylation analysis. Several of these oligosaccharides have not previously been well characterized.Abbreviations bis
bisecting GlcNAc
- DMSO
dimethylsulfoxide
- FAB
fast atom bombardment
- Fuc
l-fucose
- Gal
d-galactose
- GLC
gas-liquid chromatography
- GlcNAc or Gn
N-acetyl-d-glucosamine
- HPLC
high performance liquid chromatography
- Man or M
d-mannose
- MES
2-(N-morpholino)ethanesulfonate
- MS
mass spectrometry
- NMR
nuclear magnetic resonance
- PIPES
piperazine-N,N-bis(2-ethane sulfonic acid)
the nomenclature of the oligosaccharides is shown in Table 1. 相似文献
8.
9.
Two analogues of angiotensin III were compared as antagonists of the pressor response to angiotensin II (ANG II) and angiotensin III (ANG III) in conscious, unrestrained rats. Dose-mean arterial pressure (MAP) response curves were obtained for ANG II and ANG III in the absence or presence of [Ile7]ANG III (1.3 x 10(-7) mol/kg) or [Sar1 Ile7]ANG III (1.2 x 10(-7) mol/kg). In the presence of [Ile7]ANG III, the dose-MAP response curves for ANG II and ANG III were significantly displaced to the right. [Ile7]ANG III behaved as a partial agonist on ANG II but not ANG III receptors. In the presence of [Sar1 Ile7]ANG III, the dose-MAP response curve for ANG III but not ANG II was significantly displaced to the right. This suggests that [Sar1 Ile7]ANG III is a selective antagonist of ANG III in the vasculature. [Ile7]ANG III, on the other hand, antagonizes both ANG II and ANG III receptors. Our results support the hypothesis of the existence of a sub-class of angiotensin receptors activated by ANG III in the vascular smooth muscle. 相似文献
10.
Cibacron blue T_3GA与溴化氰活化的Sepharose 4B偶联后,产生一种能有效地分离有机磷水解酶的吸附剂。用0.15mol/L MgCl_2溶液从黄杆菌P3—2细胞抽提出的粗酶液通过柱层析分离,即可得到纯化8倍、酶活性回收率为269.4%的纯酶制品。该酶制品用凝胶电泳测是均一的。 相似文献