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1.
Molecular Biology Reports - This work aims to evaluate the renoprotective effect of luteolin on expression of Nrf2 and miR320 in ischemia–reperfusion (I/R) injury in rats. Thirty rats were...  相似文献   
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The fatty acid composition of constituent phospholipids and the cholesterol content of rat liver plasma membranes were determined subsequent to maternal alcohol ingestion during pregnancy and lactation. The alcoholic group was given a liquid Metrecal diet containing 37% ethanol-derived calories. The control group was pair-fed an isocaloric sucrose/Metrecal diet. Litters were killed for lipid analyses at days 5, 15 and 25 after birth. These studies revealed that the total phospholipid phosphorus was similar and increased significantly with age in both groups. Cholesterol also increased significantly with age in both groups but was greater in the alcoholic pups, resulting in a higher cholesterol/phospholipid molar ratio. While the phosphatidylethanolamine (PE) content increased with age in both groups, that of sphingomyelin decreased. Phosphatidylserine + phosphatidylinositol (PS + PI) was significantly higher in the control group at all ages studied. A consistent increase of C22:6 in phosphatidylcholine (PC), sphingomyelin, PS + PI and in the total phospholipid fraction from alcoholic pups was observed. Although other fatty acid changes were found in PC, PS + PI and sphingomyelin, PE was not affected. These results suggest that specific adaptive changes were induced in the liver plasma membrane lipids of the progeny from alcoholic rats.  相似文献   
4.
The mouse submaxillary proteases (A + D), the isolation and properties of which were previously described by us, hydrolyze only arginyl bonds in proteins. Formol titrations and peptide mapping on digests of polyarginine, polylysine, lysozyme, histone, and insulin suggested this specificity. Amino acid compositions of peptides from lysozyme and insulin showed that most but not all arginyl bonds were hydrolyzed but that no lysyl bonds were split. The proteases should be useful in the sequencing of proteins.  相似文献   
5.

Introduction  

The efficacy and the optimal type and volume of aerobic exercise (AE) in fibromyalgia syndrome (FMS) are not established. We therefore assessed the efficacy of different types and volumes of AE in FMS.  相似文献   
6.

Colloidal nanoparticles (NPs) interact with biological fluids such as human plasma to form a protein coating (corona) on the surface of NPs (NP-protein complex). However, the impact of size and type of NPs on binding of the hard corona to the surface of NPs as well as damping of their optical spectra has not been systematically explored. To elucidate the interaction between biological environment (human plasma) and NPs, a photophysical measurement was conducted to quantify the interaction of two different types of NPs (gold (Au) and silver (Ag)) with common human plasma proteins. The colloidal AuNPs and AgNPs were electrostatically stabilized and varied in diameter from 10 to 80 nm in the presence of common human plasma. The sizes of the NPs were determined using transmission electron microscopy (TEM). Optical absorption spectra were obtained for the complexes. Dynamic light scattering (DLS) measurement and zeta potential were used to characterize the sizes, hydrodynamic diameters, and surface charges of the protein-NPs complexes. Protein separation was performed using sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) to isolate and identify the protein bands. The absorption of proteins to the NPs was found to be strongly dependent on the size and type of NPs. The distance between surface of NPs by absorbed protein bound to the NPs gradually increased with size of NPs, particularly for AgNPs with primary diameter of < 50 nm. The chi-square test proved that AgNPs are a good candidate in sensing the protein complex in human plasma compared with AuNPs mainly for the AgNPs with diameter sized 50 nm.

  相似文献   
7.
Molecular Biology Reports - Among different pathological mechanisms, neuronal loss and neurogenesis impairment in the hippocampus play important roles in cognitive decline in Alzheimer’s...  相似文献   
8.

Noble metals, especially Ag and Au nanostructures, have unique and adjustable optical attributes in terms of surface plasmon resonance. In this research, the effect of Ag and Au nanoparticles with spherical and rod shapes on the light extraction efficiency and the FWHM of OLED structures was investigated using the finite difference time domain (FDTD) method. The simulation results displayed that by changing the shape and size of Ag and Au nanostructures, the emission wavelength can be adjusted, and the FWHM can be reduced. The presence of Ag and Au nanoparticles in the OLEDs showed a blue and red shift of the emission wavelength, respectively. Also, the Ag and Au nanorods caused a significant reduction in the FWHM and a shift to the longer wavelengths in the structures. The structures containing Ag nanorods showed the narrowest FWHM and longer emission wavelength than the other structures.

  相似文献   
9.

Background

The exact mechanisms of morphine-induced dependence and withdrawal symptoms remain unclear. In order to identify an agent that can prevent withdrawal syndrome, many studies have been performed. This study was aimed to evaluate the effect of gap junction blockers; carbenoxolone (CBX) or mefloquine (MFQ); on morphine withdrawal symptoms in male rat.Adult male Wistar rats (225 – 275 g) were selected randomly and divided into 10 groups. All groups underwent stereotaxic surgery and in order to induce dependency, morphine was administered subcutaneously) Sc) at an interval of 12 hours for nine continuous days. On the ninth day of the experiment, animals received vehicle or CBX (100, 400, 600 μg/10 μl/rat, icv) or MFQ (50, 100 and 200 μg/10 μl/rat, icv) after the last saline or morphine (Sc) injection. Morphine withdrawal symptoms were precipitated by naloxone hydrochloride 10 min after the treatments. The withdrawal signs including: jumping, rearing, genital grooming, abdomen writhing, wet dog shake and stool weight, were recorded for 60 minutes.

Results

Results showed that CBX and MFQ decreased all withdrawal signs; and the analysis indicated that they could attenuate the total withdrawal scores significantly.

Conclusion

Taking together it is concluded that gap junction blockers prevented naloxone-precipitated withdrawal symptoms.  相似文献   
10.
Colorectal cancer (CRC) is the third most common cancer worldwide. Colorectal cancer incidence differs widely among different geographic regions. In addition to mutational changes, epigenetic mechanisms also play important roles in the pathogenesis of CRCs. O6-methylguanine-DNA methyltransferase (O 6 -MGMT) is a DNA repair protein and in the absence of MGMT activity, G-to-A transition may accumulate in the specific genes such as K-ras and p53. To identify which CpG sites are critical for its downregulation, we analyzed the methylation status of the MGMT gene promoter in two sites in CRC patients. Then we compared the frequency of their methylation changes with the results of our previously reported K-ras gene mutation, APC2 and p16 methylation. MGMT methylation was examined in 92 tumor samples. A methylation specific PCR (MSP) method was performed for two loci of MGMT gene which described as MGMT-A and MGMT-B. The prevalence of MGMT-A, and MGMT-B methylation was 49/91 (53.8 %), and 83/92 (90.2 %), respectively. We detected high frequency of MGMT-B but not MGMT-A methylation in tumor tissues with APC2 methylation. Our results showed that MGMT-B methylation is significantly associated with K-ras gene mutation rather than MGMT-A (p = 0.04). Simultaneously, an inverse correlation was found between p16 and MGMT-B methylation simultaneously (p = 0.02). Our study indicated that hypermethylation of the specific locus near the MGMT start codon is critical for cancer progression. MGMT-B assessment that is associated with K-ras mutation can have a prognostic value in patients with CRC.  相似文献   
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