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131.
A UPLC/TOF-MS-based metabonomic study was conducted to assess the holistic efficacy of Traditional Chinese Medicine Shuanglong Formula (SLF) for myocardial infarction in rats. Thirty male Sprague-Dawley rats were randomly divided into five groups after surgery. The Panax ginseng group, Salvia miltiorrhiza group, and SLF group were treated with water extractions of Panax ginseng (PG), Salvia miltiorrhiza (SM), and SLF (the ratio of SM to PG was 3:7) at a dose of 5 g/kg·w·d for 21 consecutive days, respectively; the model group and sham surgery group were both treated with 0.9% saline solution. Urinary samples for metabonomic study, serum samples for biochemical measurement, and heart samples for histopathology were collected. As a result, metabonomics-based findings such as the PCA and PLS-DA plotting of metabolic state and analysis of potential biomarkers in urine correlated well to the assessment of serum biochemistry and histopathological assay, confirming that SLF exerted synergistic therapeutic efficacies to exhibit better effect on MI compared to PG or SM. The shifts in urinary TCA cycle as well as pentose phosphate pathway suggested that SLF may diminish cardiac injury of MI with its potential pharmacological effect in the regulation of myocardial energy metabolism.  相似文献   
132.
The aim of this study was to use a two steps strategy metabolomics to screen/identify and validate novel metabolic biomarker(s) for epithelial ovarian cancer (EOC). In the screening step, serum samples from 27 healthy women, 28 benign ovarian tumors, and 29 EOCs were analyzed by using LC-MS based nontargeted metabolomics. The three groups were separated with OSC filtered PLS-DA model, and six metabolites (27-nor-5β-cholestane-3,7,12,24,25 pentol glucuronide (CPG), phenylalanine, glycocholic acid, propionylcarnitine, Phe-Phe and Lyso PC (18:2)) were considered as potential biomarker candidates. In the validation step, the six metabolites were analyzed in targeted metabolomics by LC-selective ion monitoring mass spectrometry in another 685 serum samples with various clinical backgrounds. As a result, CPG was evaluated to be a potential biomarker and its content was elevated in EOC tissues compared with benign ovarian tumor tissues (p = 0.0005). Besides, CPG levels were found to be up-regulated in early stage EOC and in the three types of EOC histological types. Other variables such as nonovarian diseases, medicine consumption, gynecological inflammations, and menopausal state did not interfere in using CPG as diagnosis marker. CPG was found to be complementary to CA125. Our findings suggest that CPG can be considered a statistical relevant biomarker of EOC, ready for early stage detection.  相似文献   
133.
Recombinant human keratinocyte growth factor-2 (rhKGF-2) has previously been expressed in Escherichia coli using isopropyl-β-d-thiogalactopyranoside (IPTG), a non-metabolizable and expensive compound, as the inducer. In order to determine whether IPTG could be replaced with the cheap and natural lactose to induce rhKGF-2 expression, we examined the expression of rhKGF-2 in flask culture and 30-l fermentation using lactose as the inducer. The optimized fermentation induced with lactose resulted in 1,382 g of cell mass, corresponding to a 84% enhancement in cell mass compared with IPTG induction. While the expression level of rhKGF-2 induced with lactose was comparable to that induced with IPTG, the solubility of target protein was increased by lactose induction than by IPTG induction. The recombinant protein was further purified by cation exchange and heparin-affinity chromatography. 255 milligrams of pure rhKGF-2 was achieved per liter culture by lactose induction, 52% higher than that obtained by IPTG induction. A preliminary biochemical characterization of purified rhKGF-2 was performed by Western blotting and mitogenic activity analysis, and the results demonstrated that the purified lactose-induced rhKGF-2 could react with anti-human KGF-2 antibody and stimulate the proliferation of FGFR2-IIIb-transfected mouse BaF3 cells as IPTG-induced rhKGF-2 could do.  相似文献   
134.
Liu Q  Guan L  Huang B  Li W  Su Q  Yu M  Xu X  Luo T  Lin S  Sun X  Chen M  Chen X 《Cell biology international》2011,35(6):631-638
Adult peripheral blood-derived cells are able to differentiate into a variety of cell types, including nerve cells, liver-like cells and epithelial cells. However, their differentiation into retina-like cells is controversial. In the present study, transdifferentiation potential of human adult peripheral blood mononuclear cells into retina-like cells and integration into the retina of mice were investigated. Freshly isolated adult peripheral blood mononuclear cells were divided into two groups: cells in group I were cultured in neural stem cell medium, and cells in group II were exposed to conditioned medium from rat retinal tissue culture. After 5 days, several distinct cell morphologies were observed, including standard mononuclear, neurons with one or two axons and elongated glial-like cells. Immunohistochemical analysis of neural stem cell, neuron and retina cell markers demonstrated that cells in both groups were nestin-, MAP2 (microtubule-associated protein)- and GFAP (glial fibrillary acidic protein)-positive. Flow cytometry results suggested a significant increase in nestin-, MAP2- and CD16-positive cells in group I and nestin-, GFAP-, MAP2-, vimentin- and rhodopsin-positive cells in group II. To determine survival, migration and integration in vivo, cell suspensions (containing group I or group II cells) were injected into the vitreous or the peritoneum. Tissue specimens were obtained and immunostained 4 weeks after transplantation. We found that cells delivered by intravitreal injection integrated into the retina. Labelled cells were not detected in the retina of mice receiving differentiated cells by intraperitoneal injection, but cells (groups I and II) were detected in the liver and spleen. Our findings revealed that human adult peripheral blood mononuclear cells could be induced to transdifferentiate into neural precursor cells and retinal progenitor cells in vitro, and the differentiated peripheral blood mononuclear cells can migrate and integrate into the retina in vivo.  相似文献   
135.
136.
Ma N  Liu Y  Fu XM  Li N  Wang CX  Zhang H  Qian RB  Xu HS  Hu X  Zhang DR 《PloS one》2011,6(1):e16560

Background

The default mode network (DMN) is a set of brain regions that exhibit synchronized low frequency oscillations at resting-state, and is believed to be relevant to attention and self-monitoring. As the anterior cingulate cortex and hippocampus are impaired in drug addiction and meanwhile are parts of the DMN, the present study examined addiction-related alteration of functional connectivity of the DMN.

Methodology

Resting-state functional magnetic resonance imaging data of chronic heroin users (14 males, age: 30.1±5.3 years, range from 22 to 39 years) and non-addicted controls (13 males, age: 29.8±7.2 years, range from 20 to 39 years) were investigated with independent component analysis to address their functional connectivity of the DMN.

Principal Findings

Compared with controls, heroin users showed increased functional connectivity in right hippocampus and decreased functional connectivity in right dorsal anterior cingulate cortex and left caudate in the DMN.

Conclusions

These findings suggest drug addicts'' abnormal functional organization of the DMN, and are discussed as addiction-related abnormally increased memory processing but diminished cognitive control related to attention and self-monitoring, which may underlie the hypersensitivity toward drug related cues but weakened strength of cognitive control in the state of addiction.  相似文献   
137.
Zhang X  Yuan Q  Tang W  Gu J  Osei K  Wang J 《PloS one》2011,6(11):e27647
Our recent studies have uncovered that aggregation-prone proinsulin preserves a low relative folding rate and maintains a homeostatic balance of natively and non-natively folded states (i.e., proinsulin homeostasis, PIHO) in β-cells as a result of the integration of maturation and disposal processes. Control of precursor maturation and disposal is thus an early regulative mechanism in the insulin production of β-cells. Herein, we show pathways involved in the disposal of endogenous proinsulin at the early secretory pathway. We conducted metabolic-labeling, immunoblotting, and immunohistochemistry studies to examine the effects of selective proteasome and lysosome or autophagy inhibitors on the kinetics of proinsulin and control proteins in various post-translational courses. Our metabolic-labeling studies found that the main lysosomal and ancillary proteasomal pathways participate in the heavy clearance of insulin precursor in mouse islets/β-cells cultured at the mimic physiological glucose concentrations. Further immunoblotting and immunohistochemistry studies in cloned β-cells validated that among secretory proteins, insulin precursor is heavily and preferentially removed. The rapid disposal of a large amount of insulin precursor after translation is achieved mainly through lysosomal autophagy and the subsequent basal disposals are carried out by both lysosomal and proteasomal pathways within a 30 to 60-minute post-translational process. The findings provide the first clear demonstration that lysosomal and proteasomal pathways both play roles in the normal maintenance of PIHO for insulin production, and defined the physiological participation of lysosomal autophagy in the protein quality control at the early secretory pathway of pancreatic β-cells.  相似文献   
138.
Zhang Y  Lin X  Desrosiers M  Zhang W  Meng N  Zhao L  Han D  Zhang L 《PloS one》2011,6(6):e21769

Objective

Interleukin-1 receptor-associated kinase-4 (IRAK-4) encodes a kinase that is essential for NF-kB activation in Toll-like receptor and T-cell receptor signaling pathways, indicating a possible crosstalk between innate and acquired immunities. We attempted to determine whether the polymorphisms in the Interleukin-1 receptor-associated kinase-4 (IRAK-4) gene are associated with allergic rhinitis (AR) in the Han Chinese population.

Methods

A population of 379 patients with AR and 333 healthy controls was studied. Blood was drawn for DNA extraction and total serum immunoglobulin E (IgE). A total of 11 single nucleotide polymorphisms (SNPs) in IRAK-4 were selected and individually genotyped.

Results

Significant allelic differences between cases and controls were obtained for the SNP of rs3794262 in the IRAK-4 gene. In the stratified analysis for gender, two SNPs (rs4251431 and rs6582484) in males appeared as significant associations. Subgroup analysis for the presence of different allergen sensitivities displayed associations only in the house dust mite-allergic cohorts (rs3794262, rs4251481). None of the selected SNPs in IRAK-4 was associated with total IgE level. The haplotype analyisis indicated GCCTGCGA was significantly associated with AR. The SNP-SNP interaction information analysis indicated that the selected sets of polymorphisms had no synergistic effect.

Conclusions

Our findings did not support the potential contribution of the IRAK-4 gene to serum IgE levels. However, the results demonstrated a gender- and allergen-dependant association pattern between polymorphisms in IRAK-4 and AR in Chinese population.  相似文献   
139.
140.
Increased vascular permeability is an early event characteristic of tissue ischemia and angiogenesis. Although VEGF family members are potent promoters of endothelial permeability the role of placental growth factor (PlGF) is hotly debated. Here we investigated PlGF isoforms 1 and 2 and present in vitro and in vivo evidence that PlGF-1, but not PlGF-2, can inhibit VEGF-induced permeability but only during a critical window post-VEGF exposure. PlGF-1 promotes VE-cadherin expression via the trans-activating Sp1 and Sp3 interaction with the VE-cadherin promoter and subsequently stabilizes transendothelial junctions, but only after activation of endothelial cells by VEGF. PlGF-1 regulates vascular permeability associated with the rapid localization of VE-cadherin to the plasma membrane and dephosphorylation of tyrosine residues that precedes changes observed in claudin 5 tyrosine phosphorylation and membrane localization. The critical window during which PlGF-1 exerts its effect on VEGF-induced permeability highlights the importance of the translational significance of this work in that PLGF-1 likely serves as an endogenous anti-permeability factor whose effectiveness is limited to a precise time point following vascular injury. Clinical approaches that would pattern nature's approach would thus limit treatments to precise intervals following injury and bring attention to use of agents only during therapeutic windows.  相似文献   
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