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61.
Oxytocin (OT) is essentially associated with uterine contraction during parturition and milk ejection reflex. Although several studies implicate the role of OT in anti-inflammatory, anti-oxidative and anti-apoptotic pathways, there is a lack of data with regard to the protective effects of oxytocin in neurodegenerative models such as Parkinson's disease (PD). The present study was undertaken to investigate the neuroprotective effects of oxytocin (OT) on rotenone-induced PD in rats. Twenty adult Sprague-Dawley rats were injected with rotenone (3 μg/μl in DMSO) or vehicle (1 μl DMSO) into the left substantia nigra pars compacta (SNc) and ventral tegmental area (VTA) under stereotaxic surgery, and PD model was assessed by rotational test ten days after drug infusion. The valid PD rats were randomly divided into two groups; Group 1 (n = 7) and Group 2 (n = 7) were administered saline (1 ml/kg/day, i.p.) and oxytocin (160 μg/kg/day, i.p.) through 20 days, respectively. The effects of OT treatment were evaluated by behavioral, histological and immunohistochemical parameters. Apomorphine-induced stereotypic rotations in PD rats were significantly inhibited by OT treatment (p < 0.05). In addition, immunohistochemical studies clearly demonstrated the suppression of Bax, caspase-3, caspase-8 and elevation of Bcl-2 and tyrosine hydroxylase immunoexpression in OT-treated rats compared to saline group. Our findings suggest that oxytocin may have cytoprotective and restorative effects on dopaminergic neurons against rotenone-induced injury. The underlying mechanism may be associated with the inhibition of apoptotic pathways.  相似文献   
62.
Karakutuk I  Ak F  Okay O 《Biomacromolecules》2012,13(4):1122-1128
Silk fibroin hydrogels with tunable properties could be obtained from aqueous fibroin solutions (4.2 w/v %) in a short period of time. This was achieved by the addition of ethylene glycol diglycidyl ether (EGDE) into the reaction solution. Introduction of EGDE cross-links between the fibroin molecules decreases the mobility of the chains, which triggers the conformational transition from random-coil to β-sheet structure and hence fibroin gelation. Dynamic rheological measurements conducted at 50 °C show the formation of strong to weak hydrogels depending on the pH of the reaction solution. Although EGDE attacks the amino groups of fibroin and forms interstrand cross-links, β-sheets acting as physical cross-links dominate the elasticity of the hydrogels. Mechanical response of low-modulus fibroin hydrogels formed above pH 9.7 is highly nonlinear with strong strain hardening behavior (700%) arising from the alignment of the crystallizable amino acid segments.  相似文献   
63.
Vascular endothelial growth factor (VEGF) is the important angiogenic factor associated with tumor growth and metastasis in a wide variety of solid tumors. The aim of this study is to investigate the tumor suppressive effect of chitosan/small interfering RNA (siRNA)-VEGF nanoplexes in the rat breast cancer model. Chitosan/siRNA nanoplexes (siVEGF-A, siVEGFR-1, siVEGFR-2) and NRP-1 were prepared in a 15 to1 ratio and injected (intratumorally) into the breast-tumor-bearing Sprague-Dawley rats. Tumor volumes were measured during 21 days. To investigate the effect of chitosan/siRNA nanoplexes on VEGF expression in tumors, VEGF was analyzed with immunohistochemistry and western blotting. The mRNA levels of VEGF in tumor samples were determined with real-time PCR (RT-PCR). After siRNA treatment, a marked reduction in tumor volumes was measured in complex-injected rats (97%). Free siRNA injection showed lower tumor inhibition. Reduction of VEGF protein was also shown with western blotting and immunohistochemistry. Similar results were obtained with RT-PCR also. These results indicate that the chitosan/siRNA targeting to VEGF nanoplexes have a remarkably suppressive effect on VEGF expression and tumor volume in breast cancer model of rats.  相似文献   
64.
Terpene derivatives converted by microbial biotransformation constitute an important resource for natural pharmaceutical, fragrance, and aroma substances. In the present study, the monoterpene α-phellandrene was biotransformed by 16 different strains of microorganisms (bacteria, fungi, and yeasts). The transformation metabolites were initially screened by TLC and GC/MS, and then further characterized by NMR spectroscopic techniques. Among the six metabolites characterized, 6-hydroxypiperitone, α-phellandrene epoxide, cis-p-menth-2-en-1-ol, and carvotanacetone, which originated from (-)-(R)-α-phellandrene, are reported for the first time in this study. Additionally, the substrate and the metabolite 5-p-menthene-1,2-diol were subjected to in vitro antibacterial and anticandidal tests. The metabolite showed moderate-to-good inhibitory activities (MICs=0.125 to >4?mg/ml) against various bacteria and especially against Candida species in comparison with its substrate (-)-(R)-α-phellandrene and standard antimicrobial agents.  相似文献   
65.
The cyclin-dependent kinase Cdk1 and the related kinase Ime2 act in concert to trigger progression of the meiotic cell cycle in the yeast Saccharomyces cerevisiae. These kinases share several functions and substrates during meiosis, but their regulation seems to be clearly different. In contrast to Cdk1, no cyclin seems to be involved in the regulation of Ime2 activity. Ime2 is a highly unstable protein, and we aimed to elucidate the relevance of Ime2 instability. We first determined the sequence elements required for Ime2 instability by constructing a set of deletions in the IME2 gene. None of the small deletions in Ime2 affected its instability, but deletion of a 241 amino acid C-terminal region resulted in a highly stabilized protein. Thus, the C-terminal domain of Ime2 is important for mediating protein instability. The stabilized, truncated Ime2 protein is highly active in vivo. Replacement of the IME2 gene with the truncated IME2ΔC241 in diploid strains did not interfere with meiotic nuclear divisions, but caused abnormalities in spore formation, as manifested by the appearance of many asci with a reduced spore number such as triads and dyads. The truncated Ime2 caused a reduction of spore number in a dominant manner. We conclude that downregulation of Ime2 kinase activity mediated by the C-terminal domain is required for the efficient production of normal four-spore asci. Our data suggest a role for Ime2 in spore number control in S. cerevisiae.  相似文献   
66.
Fairmount 1 thorny” (“FM1 thorny”) (a Rosa multiflora Thunb ex. J. Murr.) and a thornless sport of “FM1 thorny” (“Fairmount 1” (“FM1”)) were established in vitro to investigate chimeral segregation under various levels of BA and to obtain a pure thornless rose. While the chimeral thornless sport was expected to segregate in vitro and yield both thorny and thornless plantlets, “FM1 thorny” was to yield only thorny plants. “FM1” segregated in vitro into its constituent genotypes and yielded thorny and thornless plantlets, suggesting that “FM1” is chimeral. “FM1 thorny” produced only thorny plants in vitro. These results indicate that the “FM1 thorny” clone was not chimeral (pure thorny) and that the thornless regenerates of “FM1” did not develop via somaclonal variation. There was a significant linear relationship between increasing BA concentration and the percentage of thorny plants. Among a population of 690 tissue culture derived plants from all the BA experiments, 6 plants were classified as pure thornless plants 1 year later.  相似文献   
67.
Biological decolorization of Benazol Black ZN, a reactive azo-type textile dyestuff, was comparatively studied using 3 different commercial-type white rot fungi strains (Pleurotus ostreatus, Pleurotus cornucopiae var. citrinopileatus, Pleurotus djamor, and 2 wild types of P. ostreatus (MCC07 and MCC20) isolated from the nature. The initial dye concentrations in the medium were 500 and 1000 mg.L-1. All the organisms studied decolorized Benazol Black ZN to varying degrees. At low dye concentration, both commercial and wild type of P. ostreatus resulted in the best decolorization, conversely, wild-type P. ostreatus (MCC07) was found to be much more robust against increasing dye concentration and provided the best decolorization efficiency at high dye concentration.  相似文献   
68.
In this study, cultivation of oyster mushroom, Pleurotus ostreatus, on wheat straw substrate containing tap water and olive mill effluent (OME) mixture containing varying volume of OME was studied in order to investigate the feasibility of using OME as an alternative wetting agent and OME's impact on some fundamental food quality characteristics of mushrooms. Time period for mycelial colonization, primordium initiation and first harvest were comparatively evaluated with the control group. It was shown that the use of OME and tap water mixture consisting of OME up to 25% volumetrically was possible for the purpose of commercial mushroom production. Experimental results obtained from substrate containing 25% OME mixture showed no statistically significant difference compared to control group. The negative effects of increasing volume of OME in the mixture were also indicated by bioefficiency, which was found to be 13.8% for substrates wetted with 100% OME, whereas bioefficiency was 53.6% for control group. Increasing volume of OME in the mixture resulted in deformation of fruit body shape, whereas no significant difference in food quality was observed due to the higher amount of OME. This work suggested that the use of OME up to 25% as moisturizer could be considered, especially for the locations having significant number of olive mills and mushroom producers, both as an environmentally friendly solution for the safe and ecological disposal of OME and a practical way for recovering OME's economic value thereby.  相似文献   
69.

Background

Non-invasive imaging tests are widely used in the evaluation of stable angina pectoris (SAP). Despite these tests, non-significant coronary lesions are not a rare finding in patients undergoing elective coronary angiography (CAG). Two-dimensional (2D) speckle tracking global longitudinal strain (GLS) imaging is a more sensitive and accurate technique for measuring LV function than conventional 2D methods. Layer-specific strain analysis is a relatively new method that provides endocardial and epicardial myocardial layer assessment. The aim of the present study was to evaluate longitudinal layer-specific strain (LSS) imaging in patients with suspected SAP.

Methods

Patients who underwent CAG for SAP were retrospectively screened. A total of 79 patients with no history of heart disease and wall motion abnormalities were included in the study. Forty-three patients with coronary lesions >?70% constituted the coronary artery disease (CAD) group and 36 patients without significant CAD constituted the control group. Layer-specific GLS transmural, endocardium, and epicardium values (GLS-trans, GLS-endo, and GLS-epi, respectively) were compared between the groups.

Results

Patients in the CAD group had significantly lower GLS values in all layers (GLS-trans: -18.2 + 2.4% vs -22.2 + 2.2% p?<?.001; GLS-endo: -20.8 + 2.8% vs -25.3 + 2.6%, p?<?.001; GLS-epi: 15.9 + 2.4% vs -19.5 + 1.9%, p?<?.001). Multivariate adjustment demonstrated GLS-trans as the only independent predictor of CAD [OR:0.472, CI (0.326–0.684), p?<?.001]. Additionally, the GLS values were all lower in myocardial perfusion scintigraphy (MPS) true-positive patients compared with MPS false-positive patients (GLS-trans: -17.7?±?2.4 vs. -21.9?±?2.4%, p?<?.001; GLS-endo: -20.2?±?2.9% vs -24.9?±?2.9%, P?<?.001; GLS-epi: 15.4?±?2.6% vs. -19.2?±?1.8%, P?<?.001).

Conclusion

Resting layer-specific strain as assessed by 2D speckle tracking analysis demonstrated that GLS values were reduced in all layers of myocardium with SAP and with no wall motion abnormalities. LSS analysis can improve the identification of patients with significant CAD but further prospective larger scale studies are needed to put forth the incremental value of LSS analysis over transmural GLS.
  相似文献   
70.
Length–weight (TL vs WWT) and chelae length–width (ChL vs ChW) relationships were described for juveniles, males and females, and for form I and form II males of Procambarus acutus acutus. The length–weight relationships for juveniles, form I, form II males, and females could be described as: WWT = 5 × 10−3 TL3.09, WWT = 6 × 10−3 TL3.61, WWT = 6 × 10−9 TL3.26, and WWT = 6 × 10−4 TL3.5, respectively. In all forms, growth was allometric (P < 0.05). The ancova test indicated that slopes and intercepts of the length–weight regressions were significantly different between sex and sexual stages. The regressions for chelae length–width relationships for form I and form II males, and females were: ChW = −0.81 + 0.27CL, ChW = −0.33 + 0.25CL, and ChW = −0.82 + 0.32CL, respectively. Although the slope and intercepts of regressions for ChL and ChW were similar for those of form I and form II males, the slopes and intercepts of regressions of females were significantly different from form I and form II males. No statistical difference was observed in mean ChL between form II males and females (P > 0.05), but a significant difference was detected in mean ChL between form I and form II males (P < 0.05) and form I and females (P < 0.05). Form I males had longer ChL than form II males and females. The same trend was observed in mean ChW for form I and form II males, but a significant difference was detected between form II males and females (P < 0.05). In addition, results indicated that chelae lengths and widths increased allometrically with total length (TL) for both sex and sexual stages.  相似文献   
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