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991.
Beob G. Kim Julye M. Adams Brian A. Jackson Merlin D. Lindemann 《Biological trace element research》2010,133(2):171-180
Dietary chromium(III) picolinate (CrPic) effects on circulating steroid hormones have been reported in various experimental
animals. However, direct effects of CrPic on adrenocortical steroidogenesis are uncertain. Therefore, the objective was to
determine the effects of CrPic on cortisol and dehydroepiandrosterone sulfate (DHEAs) secretion from H295R cells. In experiment
1, a 24-h exposure to CrPic (0 to 200 μM) had both linear (p < 0.001) and quadratic (p < 0.001) effects on cortisol secretion from forskolin-stimulated cells with the highest cortisol secretion at 0.1 μM of CrPic
and the lowest at 200 μM of CrPic. In experiment 2, a 48-h exposure to CrPic (200 μM) decreased cortisol (p < 0.07) release from forskolin-stimulated cells during a 24-h collection period. In experiment 3, a 48-h exposure to CrPic
(100 μM) decreased cortisol (p < 0.05) and DHEAs (p < 0.01) from forskolin-stimulated cells during a 24-h sampling period. In experiment 4, a 24-h exposure to forskolin followed
by a 24-h exposure to both forskolin and CrPic (100 and 200 μM) decreased both cortisol and DHEAs secretion (p < 0.01). This study suggests that at high concentrations, CrPic inhibits aspects of steroidogenesis in agonist-stimulated
adrenocortical cells. 相似文献
992.
Plasmacytoid dendritic cells (pDCs) represent a unique and crucial immune cell population capable of producing large amounts
of type I interferons (IFNs) in response to viral infection. The function of pDCs as the professional type I IFN-producing
cells is linked to their selective expression of Toll-like receptor 7 (TLR7) and TLR9, which sense viral nucleic acids within
the endosomal compartments. Type I IFNs produced by pDCs not only directly inhibit viral replication but also play an essential
role in linking the innate and adaptive immune system. The aberrant activation of pDCs by self nucleic acids through TLR signaling
and the ongoing production of type I IFNs do occur in some autoimmune diseases. Therefore, pDC may serve as an attractive
target for therapeutic manipulations of the immune system to treat viral infectious diseases and autoimmune diseases. 相似文献
993.
Xiaoqin Zhang Guoqiang Chen Qingsheng Xue Buwei Yu 《Cellular and molecular neurobiology》2010,30(6):885-890
Injury to the peripheral nervous system can lead to spontaneous pain, hyperalgesia and allodynia. Previous studies have shown
sprouting of Aβ-fibres into lamina II of the spinal cord dorsal horn after nerve injury and the formation of new synapses
by these sprouts. β-Catenin and menin as synaptogenic factors are critically involved in synapse formation. However, the roles
of β-catenin and menin in neuropathic pain are still unclear. Using Western blot analysis we investigated the changes of β-catenin
and menin in the spinal dorsal horn after unilateral spared nerve injury (SNI). We demonstrated an increase in both β-catenin
and menin protein levels in the ipsilateral spinal dorsal horn at days 1 and 3 following spared nerve injury (P < 0.05). These increases were associated with changes in paw withdrawal threshold to mechanical stimuli and weight bearing
deficit suggestive of pain behavior and spontaneous ongoing pain respectively. However, the injury-associated increases in
β-catenins and menins levels returned to control levels at day 14. In conclusion, these results indicate that peripheral nerve
injury induces upregulation of β-catenins and menins in the dorsal horn of the spinal cord, which may contribute to the development
of chronic neuropathic pain. Antagonists of these molecules may serve as new therapeutic agents. 相似文献
994.
Philippos Peidis Thomas Giannakouros Matthew E Burow Robert W Williams Robert E Scott 《BMC systems biology》2010,4(1):14
Background
The 250 kDa P2P-R protein (also known as PACT and Rbbp6) was cloned over a decade ago and was found to bind both the p53 and Rb1 tumor suppressor proteins. In addition, P2P-R has been associated with multiple biological functions, such as mitosis, mRNA processing, translation and ubiquitination. In the current studies, the online GeneNetwork system was employed to further probe P2P-R biological functions. Molecular studies were then performed to confirm the GeneNetwork evaluations. 相似文献995.
Jinze Noordijk C. J. M. Musters Jerry van Dijk Geert R. de Snoo 《Biodiversity and Conservation》2010,19(11):3255-3268
Sown, temporary field margins are a common agri-environment scheme (AES) in the Netherlands. Despite their wide application, though, there has been scarcely any long-term monitoring of the succession of invertebrates. In the field margins of 40 farms, invertebrate diversity and the abundance of three functional groups were assessed in relation to age. The diversity in terms of number of species groups was found to increase with the age of the margins. The abundance of herbivores and detritivores also showed a positive correlation with the age of the margins. However, the abundance of predators decreased with increasing age. Older margins showed a higher total vegetation cover and fewer plant species, also resulting in lower plant species evenness. We suggest several changes to the current AES regulations. For the conservation of invertebrate diversity, longer-lasting field margins are desirable. In addition, old margins are favoured by detritivores, a group that has particular difficulty finding suitable habitats in agricultural landscapes. However, such margins are less favourable from an agricultural perspective, as they appear unsuitable for high abundances of potentially useful predators and the high vegetation cover attracts many potentially harmful herbivores. To circumvent this, the AES might be extended by incorporating hay-making, which would reduce standing biomass and might lead to more predators and fewer herbivores. 相似文献
996.
Senka S. Vidović Ibrahim O. Mujić Zoran P. Zeković Žika D. Lepojević Vesna T. Tumbas Aida I. Mujić 《Food biophysics》2010,5(1):49-58
Considering the growing interest for mushrooms and the demand search of natural antioxidants sources, the aim of this study
was to investigate the antioxidant properties of two edible widely used Boletus species, Boletus edulis, and Boletus auranticus, collected from Istra region in Croatia in late summer 2007. To evaluate the antioxidant properties and content of antioxidant
compounds, scavenging capacity on DPPH˙, OH˙, and O2˙− radicals, reducing power and capacity to inhibit lipid peroxidation has been investigated. It is determined that content
of total phenols (41.82 ± 0.08 mg gallic acid equivalent per gram of dry extract) was higher for B. edulis. Using high performance liquid chromatography/diode array detector analysis, the main antioxidant compound, variegatic acid,
has been detected and quantified. 1,1-Diphenyl-2-picryl-hydrazyl-hydrate assay was used as a preliminary free radical–scavenging
evaluation. By this assay, it has been found that B. edulis dry mushroom extract exhibits 50% of inhibition value at the extract concentration of 0.016 ± 0.0003 mg/ml. The extracts
were capable of reducing iron(III) and, thus, are capable of donating electrons. Using electron paramagnetic resonance spin-trapping
and spin-probing techniques, activity against relevant reactive species, ˙OH and O2˙− radical, was analyzed for both mushroom extracts. Both investigated extracts are determined as good inhibitors for ˙OH radical
reduction, and both exhibited significant capacity for scavenging O2˙− radical and for that could help to prevent or meliorate oxidative damage. Only B. edulis extract prevents lipid peroxidation. Investigated mushroom extracts could represent easily accessible natural antioxidant
resource. 相似文献
997.
Two lactic acid bacteria (LAB) having ornithine-producing capacity were isolated from Korean natural sea salt. They were Gram-positive,
short rod-type bacteria, and able to grow anaerobically with CO2 production. The isolates grew well on MRS broth at 30–37°C and a pH of 6.5–8.0. The optimum temperature and pH for growth
are 37°C and pH 7.0. The isolates fermented D-ribose, D-galactose, D-lactose, D-maltose, Dcellobiose, D-tagatose, D-trehalose,
sucrose, D-melezitose, gentiobiose, D-glucose but not D-melibiose, inositol, and L-sorbose. The 16S rDNA sequences of the
two isolates showed 99.5% and 99.6% homology with the Weissella koreensis S5623 16S rDNA (Access no. AY035891). They were accordingly identified and named as Weissella koreensis MS1-3 and Weissella koreensis MS1-14, and produced intracellular ornithine at levels of 72 mg/100 g cell F.W. and 105 mg/100 g cell F.W. and extracellular
ornithine at levels of 4.5 mg/100 ml and 4.6 mg/100 ml medium, respectively, by culturing in MRS broth supplemented with 1%
arginine. High cell growth was maintained in MRS broth with a NaCl concentration of 0–6%. These results show for the first
time that Korean natural sea salts contain lactic acid bacteria Weissella koreensis strains having ornithine producing capacity. 相似文献
998.
Identification and characterization of adipose triglyceride lipase (ATGL) gene in birds 总被引:1,自引:0,他引:1
Qinghua Nie Yongsheng Hu Liang Xie Chengguang Zhang Xu Shen Xiquan Zhang 《Molecular biology reports》2010,37(7):3487-3493
Adipose triglyceride lipase (ATGL) is a triglyceride hydrolysis lipase and is generally related to lipid metabolism in animals.
The ATGL gene was well studied in mammals, however very less was known in birds that differed significantly with mammals for
lipid metabolism. In this study, cloning, mRNA real time and association analysis was performed to characterize the ATGL gene in birds. Results showed that the obtained ATGL gene cDNA of parrot, quail, duck were 1,651 bp (NCBI accession number: GQ221784), 1,557 bp (NCBI accession number: GQ221783)
and 1,440 bp each, encoded 481-, 482- and 279-amino acid (AA) peptide, respectively. The parrot ATGL (pATGL) gene was found to predominantly express in breast muscle and leg muscle, and very higher ATGL mRNA level was also found in heart, abdominal fat and subcutaneous fat. The quail ATGL (qATGL) gene was also predominantly expressed in breast muscle and leg muscle, and then to a much lesser degree in heart. The duck
ATGL (dATGL) gene was found to predominantly express in subcutaneous fat and abdominal fat, quite higher ATGL mRNA was also found in heart, spleen, breast muscle and leg muscle. Blast analyses indicated the high homology of ATGL and
its patatin region, and moreover, and the active serine hydrolase motif (“GASAG” for “GXSXG”) and the glycine rich motif (“GCGFLG”
for “GXGXXG”) were completely conservative among 14 species. Association analyses showed that c.950+24C>A, c.950+45C>G, c.950+73G>A,
c.950+83C>T and c.950+128delA of chicken ATGL gene (cATGL) were all significantly or highly significantly with cingulated fat width (CFW) (P < 0.05 or P < 0.01), and c.777−26C>A, c.950+45C>G, c.950+73G>A and c.950+118C>T were all significantly or highly significantly with pH
value of breast muscle (BMPH) (P < 0.05). 相似文献
999.
Miao Yin Liang Zhang Xiao-ming Sun Liu-feng Mao Jie Pan 《Molecular biology reports》2010,37(4):2049-2054
To investigate the effect of apolipoprotein E (apoE) on cytokine expression profile of the liver of young mice, quantitative
RT-PCR (qRT-PCR) assay and cytokine antibody array for multiplex analysis of 62 cytokines have been used to analyze characteristics
of expression of cytokines in the liver of 6-week-old apoE-null (apoE−/−) mice. The levels of plasma cytokines were also analyzed. The mRNA level of IL-1β, IL-2, IL-6, ICAM-1, VCAM-1, MCP-1, NF-κB
(p65), IFN-γ and IκB-α were increased significantly in apoE−/− mice comparative to wild-type (WT) mice. IL-4, IL-10 and GM-CSF, however, were slightly decreased. Compared with WT, levels
of 21 cytokines altered twofold or more in apoE−/− mice, including 10 cytokines increased and 11 decreased. Expression patterns of IL-1β, IL-2, IL-4, IL-6, IL-10, GM-CSF, IFN-γ
and VCAM-1 showed identical trend between cytokine antibody array and qRT-PCR analysis. Moreover, levels of IL-1β, IFN-γ and
IL-6 in the plasma were elevated, while IL-4 was lightly decreased in apoE−/− mice compared to those in WT mice. These results implied that promotion of type I immune response in the liver of young apoE−/− mice due to alteration of these cytokines, and the phenotypes may be caused by the regulation of NF-κB. The inflammation
and lipid metabolism dysfunction in the liver cooperated in dysfunction of the liver in young apoE−/− mice. 相似文献
1000.