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81.
Partial gene deletion is the major type of mutation leading to Duchenne muscular dystrophy (DMD) and its mild allelic form, Becker muscular dystrophy (BMD). Amplification of the genomic DNAs of 152 unrelated dystrophin patients using multiple primers detected 78 (51.3%) probands with deletion mutations. We predicted the translational reading frame for all the deletions in Egyptian dystrophin males. The frameshift rule was confirmed positively ranging for 50 to 67% of the cases depending on the type of disease. We discuss ways of accounting for some exceptions from the frameshift hypothesis in the central and proximal regions. These explanations may help in developing procedures for reducing the severity of dystrophin phenotypes to restore the correct frame by disrupting the translational fidelity. Great efforts have been put into the development of effective 'gene correction' procedures via such intrinsic mechanisms. In addition, we mapped regional difference in deletion mutation frequencies within the DMD gene locus between the different Egyptian governorates. There were no double deletions in the Egyptian dystrophin males.  相似文献   
82.
To determine whether overexpression of transforming growth factor (TGF)-alpha in the adult lung causes remodeling independently of developmental influences, we generated conditional transgenic mice expressing TGF-alpha in the epithelium under control of the doxycycline (Dox)-regulatable Clara cell secretory protein promoter. Two transgenic lines were generated, and following 4 days of Dox-induction TGF-alpha levels in whole lung homogenate were increased 13- to 18-fold above nontransgenic levels. After TGF-alpha induction, transgenic mice developed progressive pulmonary fibrosis and body weight loss, with mice losing 15% of their weight after 6 wk of TGF-alpha induction. Fibrosis was detected within 4 days of TGF-alpha induction and developed initially in the perivascular, peribronchial, and pleural regions but later extended into the interstitium. Fibrotic regions were composed of increased collagen and cellular proliferation and were adjacent to airway and alveolar epithelial sites of TGF-alpha expression. Fibrosis progressed in the absence of inflammatory cell infiltrates as determined by histology, without changes in bronchiolar alveolar lavage total or differential cell counts and without changes in proinflammatory cytokines TNF-alpha or IL-6. Active TGF-beta in whole lung homogenate was not altered 1 and 4 days after TGF-alpha induction, and immunostaining was not increased in the peribronchial/perivascular areas at all time points. Chronic epithelial expression of TGF-alpha in adult mice caused progressive pulmonary fibrosis associated with increased collagen and extracellular matrix deposition and increased cellular proliferation. Induction of pulmonary fibrosis by TGF-alpha was independent of inflammation or early activation of TGF-beta.  相似文献   
83.
Lipoplex size determines lipofection efficiency with or without serum   总被引:5,自引:0,他引:5  
In order to identify factors affecting cationic liposome-mediated gene transfer, the relationships were examined among cationic liposome/DNA complex (lipoplex)-cell interactions, lipoplex size and lipoplex-mediated transfection (lipofection) efficiency. It was found that lipofection efficiency was determined mainly by lipoplex size, but not by the extent of lipoplex-cell interactions including binding, uptake or fusion. In addition, it was found that serum affected mainly lipoplex size, but not lipoplex-cell interactions, which effect was the major reason behind the inhibitory effect of serum on lipofection efficiency. It was concluded that, in the presence or absence of serum, lipoplex size is a major factor determining lipofection efficiency. Moreover, in the presence or absence of serum, lipoplex size was found to affect lipofection efficiency by controlling the size of the intracellular vesicles containing lipoplexes after internalization, but not by affecting lipoplex-cell interactions. In addition, large lipoplex particles showed, in general, higher lipofection efficiency than small particles. These results imply that, by controlling lipoplex size, an efficient lipid delivery system may be achieved for in vitro and in vivo gene therapy.  相似文献   
84.
85.
Transesterified vegetable oils (VOs) are promising alternative diesel fuel. Waste VOs are cheap and renewable but currently disposed of inadequately. In this work, waste palm oil was transesterified under various conditions. H2SO4 and different concentrations of HCl and ethanol at different excess levels were used. Higher catalyst concentrations (1.5-2.25 M) produced biodiesel with lower specific gravity, gamma, in a much shorter reaction time than lower concentrations. The H2SO4 performed better than HCl at 2.25 M, as it resulted in lower gamma. Moreover, a 100% excess alcohol effected significant reductions in reaction time and lower gamma relative to lower excess levels. The best process combination was 2.25 M H2SO4 with 100% excess ethanol which reduced gamma from an initial value of 0.916 to a final value of 0.8737 in about 3 h of reaction time. Biodiesel had the behavior of a Newtonian fluid.  相似文献   
86.
87.
The primary aim of our meta-analysis was to evaluate the effects of cathodal transcranial direct current stimulation (c-tDCS) on sensory and pain thresholds (STh and PTh) in healthy individuals and pain level (PL) in patients with chronic pain. Electronic databases were searched for c-tDCS studies. Methodological quality was evaluated using the PEDro and Downs and Black (D&B) assessment tools. C-tDCS of the primary motor cortex (S1) increases both STh (P<0.001, effect size of 26.84%) and PTh (P<0.001, effect size of 11.62%). In addition, c-tDCS over M1 led to STh increase (P<0.005, effect size of 30.44%). Likewise, PL decreased significantly in the patient group following application of c-tDCS. The small number of studies precluded subgroup analysis. Nevertheless, meta-analysis showed that in all groups (except c-tDCS of S1) active c-tDCS and sham stimulation produced significant differences in STh/PTh in healthy and PL in patient group. This review provides evidence for the site-specific effectiveness of c-tDCS in increasing STh/PTh in healthy individuals and decreasing PL in patients with chronic pain. However, due to small sample sizes in the included studies, our results should be interpreted with caution. Given that the level of blinding was not considered in the inclusion criteria, the results of the current study should be interpreted with caution.  相似文献   
88.
A novel and highly sensitive chemiluminescence (CL) method for the determination of ethanol was developed based on the CdS quantum dots (QDs)–permanganate system. It was found that KMnO4 could directly oxidize CdS QDs in acidic media resulting in relatively high CL emission. A possible mechanism was proposed for this reaction based on UV/Vis absorption, fluorescence and the generated CL emission spectra. However, it was observed that ethanol had a remarkable inhibition effect on this system. This effect was exploited in the determination of ethanol within the concentration range 12–300 µg/L, with detection at 4.3 µg/L. In order to evaluate the capability of presented method, it was satisfactorily utilized in the determination of alcohol in real samples. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
89.
Adenosine receptors (ARs) have emerged as new drug targets. The majority of data on affinity/potency and selectivity of AR ligands described in the literature has been obtained for the human species. However, preclinical studies are mostly performed in mouse or rat, and standard AR agonists and antagonists are frequently used for studies in rodents without knowing their selectivity in the investigated species. In the present study, we selected a set of frequently used standard AR ligands, 8 agonists and 16 antagonists, and investigated them in radioligand binding studies at all four AR subtypes, A1, A2A, A2B, and A3, of three species, human, rat, and mouse. Recommended, selective agonists include CCPA (for A1AR of rat and mouse), CGS-21680 (for A2A AR of rat), and Cl-IB-MECA (for A3AR of all three species). The functionally selective partial A2B agonist BAY60-6583 was found to additionally bind to A1 and A3AR and act as an antagonist at both receptor subtypes. The antagonists PSB-36 (A1), preladenant (A2A), and PSB-603 (A2B) displayed high selectivity in all three investigated species. MRS-1523 acts as a selective A3AR antagonist in human and rat, but is only moderately selective in mouse. The comprehensive data presented herein provide a solid basis for selecting suitable AR ligands for biological studies.

Electronic supplementary material

The online version of this article (doi:10.1007/s11302-015-9460-9) contains supplementary material, which is available to authorized users.  相似文献   
90.
In this work, we introduce a deep-structured conditional random field (DS-CRF) model for the purpose of state-based object silhouette tracking. The proposed DS-CRF model consists of a series of state layers, where each state layer spatially characterizes the object silhouette at a particular point in time. The interactions between adjacent state layers are established by inter-layer connectivity dynamically determined based on inter-frame optical flow. By incorporate both spatial and temporal context in a dynamic fashion within such a deep-structured probabilistic graphical model, the proposed DS-CRF model allows us to develop a framework that can accurately and efficiently track object silhouettes that can change greatly over time, as well as under different situations such as occlusion and multiple targets within the scene. Experiment results using video surveillance datasets containing different scenarios such as occlusion and multiple targets showed that the proposed DS-CRF approach provides strong object silhouette tracking performance when compared to baseline methods such as mean-shift tracking, as well as state-of-the-art methods such as context tracking and boosted particle filtering.  相似文献   
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