79 research outputs found
Dexmedetomidine preconditioning alleviates apoptosis in rat cardiomyocytes by suppressing programmed cell death 4 (PDCD4) after myocardial ischemia-reperfusion injury
Purpose: To determine the role of dexmedetomidine (Dex) in hypoxia/reoxygenation (H/R)-induced myocardial cell injury and the possible involvement of the programmed cell death 4 (Pdcd4) gene in Dex-mediated myocardial cell apoptosis after ischemia-reperfusion (I/R) injury. Methods: An in vivo I/R-injured rat model and in vitro H/R rat cell model were evaluated to ascertain the role of Dex in apoptosis. Programmed cell death 4 (PDCD4) gene expression levels were measured after Dex preconditioning. The effects of Pdcd4 knockdown or overexpression on Dex-mediated apoptosis during H/R injury were determined. Results: Dex pretreatment alleviated myocardial infarction in rats, suppressed myocardial cell apoptosis, and inhibited PDCD4 expression (p < 0.05). Treatment with Dex also alleviated H/R-induced apoptosis in rat cardiomyocytes, while PDCD4 expression decreased after Dex treatment (p < 0.05). Moreover, PDCD4 overexpression reversed the inhibitory effect of Dex on H/R myocardial cell apoptosis. Conclusion: Dex alleviates myocardial infarction in rats via its effect on PDCD4 expression. Therefore, Dex can potentially be used for the treatment but this has to clinical studies
Medium optimization for palmarumycin C13 production in liquid culture of endophytic fungus Berkleasmium sp. Dzf12 using response surface methodology
Background: Berkleasmium sp. Dzf12, an endophytic fungus from
Dioscorea zingiberensis , was a high producer of palmarumycin C13 with
various bioactivities. In the present study, the experimental designs
based on statistics were employed to evaluate and optimize the medium
for palmarumycin C13 production in mycelia liquid culture of
Berkleasmium sp. Dzf12. Results: Among various carbon and nitrogen
sources, glucose, peptone and yeast extract were found to be the most
favourable for palmarumycin C13 production based on the
one-factor-at-a-time experiments. After Plackett-Burman test on the
medium, glucose, peptone and yeast extract were further verified to be
the most significant factors to stimulate palmarumycin C13
accumulation. These three factors (i.e., glucose, peptone and yeast
extract) were then optimized through the experiments of central
composite design (CCD) and analysis of response surface methodology
(RSM). The optimized medium compositions for palmarumycin C13
production were determined as 42.5 g/l of glucose, 6.5 g/l of peptone,
11.0 g/l of yeast extract, 1.0 g/l of KH2PO4, 0.5 g/l of MgSO4 x 7H2O,
0.05 g/l of FeSO4 x 7H2O, and pH 6.5. Under the optimal culture
conditions, the maximum palmarumycin C13 yield of Berkleasmium sp.
Dzf12 was increased to 318.63 mg/l, which was about 2.5-fold in
comparison with that (130.44 mg/l) in the basal medium. Conclusions:
The results indicate that the optimum production of palmarumycin C13 in
Berkleasmium sp. Dzf12 liquid culture can be achieved by addition of
glucose, peptone and yeast extract with their appropriate
concentrations in the modified Sabouraud medium
Carbon Nanofibers Modified Graphite Felt for High Performance Anode in High Substrate Concentration Microbial Fuel Cells
Carbon nanofibers modified graphite fibers (CNFs/GF) composite electrode was prepared for anode in high substrate concentration microbial fuel cells. Electrochemical tests showed that the CNFs/GF anode generated a peak current density of 2.42 mA cm−2 at a low acetate concentration of 20 mM, which was 54% higher than that from bare GF. Increase of the acetate concentration to 80 mM, in which the peak current density of the CNFs/GF anode greatly increased and was up to 3.57 mA cm−2, was seven times as that of GF anode. Morphology characterization revealed that the biofilms in the CNFs/GF anode were much denser than those in the bare GF. This result revealed that the nanostructure in the anode not only enhanced current generation but also could tolerate high substrate concentration
Empirical verification of heterogeneous DNA fragments generated from wheat genome-specific SSR primers
Publisher's version/PDFDue to the high polymorphisms between synthetic hexaploid wheat (SHW) and common wheat, SHW has been widely used in genetic studies. The transferability of simple sequence repeats (SSR) among common wheat and its donor species, Triticum turgidum and Aegilops tauschii, and their SHW suggested the possibility that some SSRs, specific for a single locus in common wheat, might appear in two or more loci in SHWs. This is an important genetic issue when using synthetic hexaploid wheat population and SSR for mapping. However, it is largely ignored and never empirically well verified. The present study addressed this issue by using the well-studied SSR marker Xgwm261 as an example. The Xgwm261 produced a 192 bp fragment specific to chromosome 2D in common wheat Chinese Spring, but generated a 176 bp fragment in the D genome of Ae. tauschii AS60. Chromosomal location and DNA sequence data revealed that the 176 bp fragment also donated by 2B chromosome of durum wheat Langdon. These results indicated that although a single 176 bp fragment was appeared in synthetic hexaploid wheat Syn-SAU-5 between Langdon and AS60, the fragment contained two different loci, one from chromosome 2D of AS60 and the other from 2B of Langdon which were confirmed by the segregating analysis of SSR Xgwm261 in 185 plants from a F2 population between Syn-SAU-5 and Chinese Spring. If Xgwm261 in Syn-SAU-5 was considered as a single locus in genetic analysis, distorted segregation or incorrect conclusions would be yielded. A proposed strategy to avoid this problem is to include SHW’s parental T. turgidum and Ae. tauschii in SSR analysis as control for polymorphism detection
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