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The pathological effects of exposure to an electromagnetic field (EMF) during adolescence may be greater than those in adulthood. We investigated the effects of exposure to 900 MHz EMF during adolescence on male adult rats. Twenty-four 21-day-old male rats were divided into three equal groups: control (Cont-Gr), sham (Shm-Gr) and EMF-exposed (EMF-Gr). EMF-Gr rats were placed in an EMF exposure cage (Plexiglas cage) for 1 h/day between postnatal days 21 and 59 and exposed to 900 MHz EMF. Shm-Gr rats were placed inside the Plexiglas cage under the same conditions and for the same duration, but were not exposed to EMF. All animals were sacrificed on postnatal day 60 and the hearts were extracted for microscopic and biochemical analyses. Biochemical analysis showed increased levels of malondialdehyde and superoxide dismutase, and reduced glutathione and catalase levels in EMF-Gr compared to Cont-Gr animals. Hematoxylin and eosin stained sections from EMF-Gr animals exhibited structural changes and capillary congestion in the myocardium. The percentage of apoptotic myocardial cells in EMF-Gr was higher than in either Shm-Gr or Cont-Gr animals. Transmission electron microscopy of myocardial cells of EMF-Gr animals showed altered structure of Z bands, decreased myofilaments and pronounced vacuolization. We found that exposure of male rats to 900 MHz EMF for 1 h/day during adolescence caused oxidative stress, which caused structural alteration of male adolescent rat heart tissue.  相似文献   
14.

Background  

Glycogen Synthase Kinase-3 (GSK3) activity is repressed following insulin treatment of cells. Pharmacological inhibition of GSK3 mimics the effect of insulin on Phosphoenolpyruvate Carboxykinase (PEPCK), Glucose-6 Phosphatase (G6Pase) and IGF binding protein-1 (IGFBP1) gene expression. CAAT/enhancer binding protein alpha (C/EBPα) regulates these gene promoters in liver and is phosphorylated on two residues (T222/T226) by GSK3, although the functional outcome of the phosphorylation has not been established. We aimed to establish whether CEBPα is a link between GSK3 and these gene promoters.  相似文献   
15.
A novel one-dimensional Ni(II) coordination polymer [Ni(C6H8N2)2Cr2O7]n (1) has been synthesised and characterised by elemental analyses, spectroscopic and single crystal X-ray diffraction study. Single crystal X-ray analysis revealed that the [Ni(C6H8N2)2]2+ cations are connected by μ1,5 dichromato bridges forming infinite zig-zag chain along b-axis.  相似文献   
16.
The new tripodal phosphine CH3C{CH2P(m-CF3C6H4)2}3, CF3PPP, was prepared by reacting CH3C(CH2Br)3 with Li+P(m-CF3C6H4)2, the latter being best obtained by adding Li+NiPr2 to PH(m-CF3C6H4)2. The rhodium complexes [RhCl(CO)(CF3PPP)], [Rh(LL)(CF3PPP)](CF3SO3) (LL = 2 CO or NBD), [RhX3(CF3PPP)], [RhX(MeCN)3(CF3PPP)](CF3SO3)2 (X = H and Cl), [RhCl2(MeCN)(CF3PPP)](CF3SO3) and [Rh(MeCN)3(CF3PPP)](CF3SO3)3 were prepared and characterized. The X-ray crystal structure of [Rh(NBD)(CF3PPP)](CF3SO3) is reported. The lower oxygen sensitivity of the CF3PPP rhodium(I) complexes, relative to the corresponding species with the parent ligand CH3C(CH2PPh2)3, is attributed to the higher effective nuclear charge on the metal centers caused by the presence of the six CF3 substituents on the terdentate phosphine. A similar effect may be responsible for the easier hydrolysis of the CF3PPP-containing, cationic rhodium(III) complexes relative to the corresponding compounds of the parent ligand.  相似文献   
17.
The aim of the study was to investigate the presence and distribution of PE-11, a peptide derived from chromogranin B, in the rat eye. For this purpose, newborn rats were injected with a single dosage of 50 mg/kg capsaicin subcutaneously under the neck fold and after three months, particular eye tissues were dissected and the concentration of PE-11-like immunoreactivity was determined by radioimmunoassay. Furthermore, PE-11-like immunoreactivities were characterized in an extract of the rat eye by reversed phase HPLC. Then, the distribution pattern of PE-11 was investigated in the rat eye and rat trigeminal ganglion by immunofluorescence. As a result, PE-11 was present in each tissue of the rat eye and capsaicin pretreatment led to a 88.05% (±7.07) and a 64.26% (±14.17) decrease of the levels of PE-11 in the cornea and choroid/sclera, respectively, and to a complete loss in the iris/ciliary body complex. Approximately 70% of immunoreactivities detected by the PE-11 antiserum have been found to represent authentic PE-11. Sparse nerve fibers were visualized in the corneal and uveal stroma, surrounding blood vessels at the limbus, ciliary body and choroid and in association with the dilator and sphincter muscle. Furthermore, immunoreactivity was present in the corneal endothelium. In the retina and optic nerve, glia was labeled. In the rat trigeminal ganglion, PE-11-immunoreactivity was visualized in small and medium sized ganglion cells with a diameter of up to 30 μm. In conclusion, there is unequivocal evidence that PE-11 is a constituent of capsaicin-sensitive sensory neurons innervating the rat eye and the distribution pattern is typically peptidergic in the peripheral innervation but in the retina completely atypical for neuropeptides and unique.  相似文献   
18.
A novel dinuclear [(MeOH)(L) Ni (di-μ-CCl3CO2) Ni (L)(CCl3CO2)] 1 [where L={(O)(C6H4CH=NCH2CH2NMe3)}] complex has been synthesized and characterized. Characterization based on elemental analyses, infrared and electronic spectra, thermal studies, variable temperature magnetic susceptibility measurement and crystal structure analysis. The complex crystallizes in the monoclinic system, space group P2(1)/n with a=16.818(11), b=20.386(11), c=20.589(13), β=90.94(5) and Z=8. The complex shows di-μ-trichloroacetate bridging with concatenated methanol molecule hydrogen bonded with another trichloroacetate. Magnetic susceptibility measurements of complex 1 reveal an antiferromagnetic intra-dimer interaction with the J value deduced from the spin Hamiltonian H=−JS1S2.  相似文献   
19.
We investigated the effects of different implant biomaterials on cultured canine bone marrow stromal cells (BMSC) undergoing differentiation into osteoblasts (dBMSC). BMSC were isolated from canine humerus by marrow aspiration, cultured and differentiated on calcium phosphate scaffold (CPS), hydroxyapatite, hydroxyapatite in gel form and titanium mesh. We used the MTT method to determine the effects of osteogenic media on proliferation. The characteristics of dBMSC were assessed using alizarin red (AR), immunocytochemistry and osteoblastic markers including alkaline phosphatase/von Kossa (ALP/VK), osteocalcin (OC) and osteonectin (ON), and ELISA. The morphology of dBMSC on the biomaterials was investigated using inverted phase contrast microscopy and scanning electron microscopy. We detected expression of ALP/VK, AR, OC and ON by day 7 of culture; expression increased from day 14 until day 21. CPS supported the best adhesion, cell spreading, proliferation and differentiation of BMSCs. The effects of the biomaterials depended on their surface properties. Expression of osteoblastic markers showed that canine dBMSCs became functional osteoblasts. Tissue engineered stem cells can be useful clinically for autologous implants for treating bone wounds.  相似文献   
20.

Background

Next generation sequencing technologies allow to obtain at low cost the genomic sequence information that currently lacks for most economically and ecologically important organisms. For the mallard duck genomic data is limited. The mallard is, besides a species of large agricultural and societal importance, also the focal species when it comes to long distance dispersal of Avian Influenza. For large scale identification of SNPs we performed Illumina sequencing of wild mallard DNA and compared our data with ongoing genome and EST sequencing of domesticated conspecifics. This is the first study of its kind for waterfowl.

Results

More than one billion base pairs of sequence information were generated resulting in a 16× coverage of a reduced representation library of the mallard genome. Sequence reads were aligned to a draft domesticated duck reference genome and allowed for the detection of over 122,000 SNPs within our mallard sequence dataset. In addition, almost 62,000 nucleotide positions on the domesticated duck reference showed a different nucleotide compared to wild mallard. Approximately 20,000 SNPs identified within our data were shared with SNPs identified in the sequenced domestic duck or in EST sequencing projects. The shared SNPs were considered to be highly reliable and were used to benchmark non-shared SNPs for quality. Genotyping of a representative sample of 364 SNPs resulted in a SNP conversion rate of 99.7%. The correlation of the minor allele count and observed minor allele frequency in the SNP discovery pool was 0.72.

Conclusion

We identified almost 150,000 SNPs in wild mallards that will likely yield good results in genotyping. Of these, ~101,000 SNPs were detected within our wild mallard sequences and ~49,000 were detected between wild and domesticated duck data. In the ~101,000 SNPs we found a subset of ~20,000 SNPs shared between wild mallards and the sequenced domesticated duck suggesting a low genetic divergence. Comparison of quality metrics between the total SNP set (122,000 + 62,000 = 184,000 SNPs) and the validated subset shows similar characteristics for both sets. This indicates that we have detected a large amount (~150,000) of accurately inferred mallard SNPs, which will benefit bird evolutionary studies, ecological studies (e.g. disentangling migratory connectivity) and industrial breeding programs.
  相似文献   
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