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241.
The antioxidant properties of methanol extracts of Lady’s Bedstraw (Galium verum L., Rubiaceae) herb from two different localities in Serbia were evaluated. Antioxidant activity was assessed in four different model systems. Free radical scavenging capacity (RSC) was examined by measuring the scavenging activity of extracts on 2,2-diphenyl-1-pycrylhydrazil (DPPH) and hydroxyl radical (OH), as well as on hydrogen peroxide. In addition, the protective effects of lipid peroxidation (LP) in corn oil were evaluated by the TBA-assay using the Fe2+/ascorbate system of induction. The amount of dried extract, the content of total phenolics, flavonoids and chlorophylls was also determined. Extracts from both locations expressed very strong scavenger activity, reducing the DPPH (IC50=3.10 μg/mland 8.04 μg/ml) and OH radical formation (IC50=0.05 μg/ml and 0.54 μg/ml) and neutralising H2O2 (IC50=4.98 μg/ml and 3.80 μg/ml), in a dose dependant manner. Also, examined extracts showed notable inhibition of LP (IC50=11.69 μg/ml and 19.47 μg/ml). The observed differences in antioxidant activity could be partially explained by the levels of phenolics (2.44–4.65 mg and 4.57–5.16 mg gallic acid equivalents/g dry extract), flavonoids (6.38–10.70 μg and 15.56–17.96 μg quercetin equivalents/g dry extract) and chlorophylls in the investigated Lady’s Bedstraw extracts.  相似文献   
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Recent progress in developing family-based association methods has extended their use to the analysis of quantitative traits in the offspring and to the estimation, for dichotomous traits, of the relative contribution of genetic and environmental mechanisms for parent-of-origin effects. However, many traits of interest are not naturally measured on a binary scale yet are suspected or known to be influenced by imprinted genes, and there is consequent interest in seeking evidence for parent-of-origin effects at these loci. Here we show how simple linear models can be used to estimate these parent-of-origin effects for a broad class of phenotypes; in particular, normally distributed quantitative traits are easily dealt with.  相似文献   
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The mitochondrial damage has a pivotal role in triggering apoptosis and cell death. This study assessed the effect of silibinin on optical atrophy-1 (OPA1) and mitofusin-1 (MFN1) gene expression in liver tissue during hepatic warm ischemia–reperfusion (IR). Four groups of rats, eight rats each were designed: Vehicle: the rats received normal saline and encountered to laparotomy, Sili: silibinin (60 mg/kg) was administered to animals, IR: the rats received the normal saline and insulted by liver IR procedure, and IR?+?Sili: silibinin was injected to rats. All groups were subjected to the same process of injection of the solvent or silibinin (30 min before laparotomy or ischemia and immediately after the reperfusion), intraperitoneally (IP). After 3 h of reperfusion, blood and liver tissue samples were collected for future examinations. Our results showed no significant differences between the Vehicle and Sili groups in all assessed parameters. In IR?+?Sili, the increased serum levels of AST and ALT in comparison with the control group were markedly reduced by silibinin treatment. Silibinin lowered the elevated expression of OPA1 and MFN1 mRNAs in the IR group. Histology revealed silibinin could decline tissue degeneration compared to the IR group. Electron microscopy of control and silibinin groups showed no fusion of mitochondria and tissue degradation both of which were observed in the IR group. The extent of tissue destruction and mitochondrial fusion decreased significantly with silibinin treatment. Silibinin has a protective effect on liver cells against IR induced injuries by preserving mitochondrial membrane.

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Inflammatory breast cancer (IBC), a rare form of breast cancer associated with increased angiogenesis and metastasis, is largely driven by tumor-stromal interactions with the vasculature and the extracellular matrix (ECM). However, there is currently a lack of understanding of the role these interactions play in initiation and progression of the disease. In this study, we developed the first three-dimensional, in vitro, vascularized, microfluidic IBC platform to quantify the spatial and temporal dynamics of tumor-vasculature and tumor-ECM interactions specific to IBC. Platforms consisting of collagen type 1 ECM with an endothelialized blood vessel were cultured with IBC cells, MDA-IBC3 (HER2+) or SUM149 (triple negative), and for comparison to non-IBC cells, MDA-MB-231 (triple negative). Acellular collagen platforms with endothelialized blood vessels served as controls. SUM149 and MDA-MB-231 platforms exhibited a significantly (p < .05) higher vessel permeability and decreased endothelial coverage of the vessel lumen compared to the control. Both IBC platforms, MDA-IBC3 and SUM149, expressed higher levels of vascular endothelial growth factor (p < .05) and increased collagen ECM porosity compared to non-IBCMDA-MB-231 (p < .05) and control (p < .01) platforms. Additionally, unique to the MDA-IBC3 platform, we observed progressive sprouting of the endothelium over time resulting in viable vessels with lumen. The newly sprouted vessels encircled clusters of MDA-IBC3 cells replicating a key feature of in vivo IBC. The IBC in vitro vascularized platforms introduced in this study model well-described in vivo and clinical IBC phenotypes and provide an adaptable, high throughput tool for systematically and quantitatively investigating tumor-stromal mechanisms and dynamics of tumor progression.  相似文献   
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To target disseminated tumors in vivo, transgenes [beta-galactosidase gene, green fluorescence protein (GFP) gene, herpes simplex virus thymidine kinase (HSV-TK)] were conjugated to transferrin (Tf) by a biotin-streptavidin bridging, which is stoichiometrically controllable, and Tf receptor (Tf-R) affinity chromatography, which selects Tf conjugates with intact receptor bindings sites from reacting with the linker. Tf-beta-galactosidase plasmid conjugate thus constructed was specifically transfected to human erythroleukemia cells (K562) via Tf-R without the aid of any lysosomotropic agents. The transfection efficiency of the conjugate was superior to those of lipofection (1% staining) and retroviral vector (5%) and slightly lower than that of adenovirus (70%). The high level of expression with our conjugate was confirmed using other tumor cells (M7609, TMK-1) whereas in normal diploid cells (HEL), which express low levels of Tf-R, expression was negligible. When GFP gene conjugates were systemically administered through the tail vein to nude mice subcutaneously inoculated with tumor, expression of GFP mRNA was found almost exclusively in tumors and to a much lesser extent in muscles, whereas GFP revealed by fluorescence microscopy was detected only in the former. To exploit a therapeutic applicability of this method, suicide gene therapy using Tf-HSV-TK gene conjugate for massively metastasized k562 tumors in severe combined immune-deficient mice was conducted, and a marked prolongation of survival and significant reduction of tumor burden were confirmed. Thus, this method could also be used for gene therapy to disseminated tumors.  相似文献   
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Plant-derived polymers are widely used in the pharmaceutical industry due to their emollient, lack of toxicity, and irritating nature and low cost. In this work, basil seed mucilage was dried using supercritical carbon dioxide phase inversion technique to form a nanometric structure. The obtained polymeric structures were characterized by scanning electron microscopy (SEM), Brunauer–Emmett–Teller (BET) method, and Fourier transform infrared spectroscopy (FTIR) and compared with the oven-derived sample group. It was demonstrated that the product morphology could be controlled by altering the composition of methanol which functioned as the co-solvent in the nonsolvent stream. The most homogeneous product (60-nm mean pore size diameter, 78 m2/g BET surface area with no agglomeration) was obtained with 2.5% methanol. The FTIR data showed that the presence of hydroxyl and carboxyl groups suggested the bioadhesive property of basil seed mucilage was good and many active pharmaceutical compounds might be loaded to the resultant nanometric structure to enhance drug release. Furthermore, the FTIR analyses indicated that the nature of the final product did not change during the supercritical drying procedure.KEY WORDS: basil seed gum, drug delivery, FTIR characterization, nanostructure, natural polymer, supercritical phase inversion  相似文献   
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Probiotics and Antimicrobial Proteins - Regulation of immune responses is among the beneficial effects of probiotic bacteria on human health. In this study, we aim to investigate the effect of...  相似文献   
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Obsessive-compulsive disorder (OCD) is a heterogenous disorder with different clinical presentations. The most common symptoms are those that involve contamination, possible harm, ordering/symmetry, aggressive/sexual/religious concerns and hoarding. A variety of less common symptoms have been described. Unusual OCD symptoms may lead to misdiagnosis, inappropriate treatment with possible serious side effects. In this report we present a case of an adolescent girl in which unusual OCD presentation and symptoms were misinterpreted to represent psychosis and exacerbation of OCD symptoms with risperidone and clozapine treatment. We discuss the possible pathophysiological mechanisms of OCD symptom exacerbation, clinical implications, and successful management of this case, with fluvoxamine therapy. This case may represent the first report of musical obsessions successfully managed with fluvoxamine therapy.  相似文献   
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