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81.
Parkinson's disease (PD) consists of a neurodegenerative pathology that has received a considerable amount of attention because of its clinical manifestations. The most common treatment consists of administering the drugs levodopa and biperiden, which reduce the effectiveness of the disease and the progress of its symptoms. However, phytotherapy treatment of PD has shown great potential in retarding the loss of dopaminergic neurons and minimizing the behavioral abnormalities. The aim of this study is to systematically review the use of supplemental herbal plants with cellular protective effect and behavioral activity in in vivo and in vitro experimental models. A total of 20 studies were summarized, where the effectiveness of herbal extracts and their isolated bioactive compounds was observed in animal models for PD. The main neurochemical mechanisms found in these studies are schematically represented. The herbal extracts and their biocompounds have antioxidant, anti‐apoptotic, and antiinflammatory properties, which contribute to avoiding neuronal loss. Reports show that besides acting on the biosynthesis of dopamine and its metabolites, these compounds prevent D2 receptors' hypersensitivity. It is suggested that further studies need be conducted to better understand the mechanisms of action of the bioactive compounds distributed in these plants. Copyright © 2017 John Wiley & Sons, Ltd.  相似文献   
82.
To describe clinical, pulmonary function, and chest tomography profiles in a 5-year follow-up of infants with adenovirus pneumonia and determine the factors that potentially contributed to the development of bronchiolitis obliterans (BO). We prospectively assessed 45 hospitalized infants with adenovirus pneumonia with additional follow-up for 5 years. At the end of the study, pulmonary function by impulse oscillometry technique (IOS) and chest tomography were performed in the 38 surviving patients (mean 5.7 years of age). We divided the population between those who developed chest tomography evidence of BO and those who did not. Most of the children developed adenovirus infection before 2 years of age. During the 5 years of follow-up, almost half (47.4%) developed BO. Children who developed BO had significantly more respiratory compromise (intensive care admission, need for mechanical ventilation and for oxygen therapy, and systemic corticosteroid and beta agonist use) during their adenovirus pneumonia episode than those who did not develop BO. Only 33.3% of children with BO had normal impedance compared with 85% in the no BO group. Children who developed BO had significantly higher levels of Zrs, R5, X5 and predicted Zrs, R5, and X5 and frequency. However, there were no differences in the beta 2 agonist response between the children with and without BO (94% vs. 80%, respectively). This study represents the spectra of adenovirus pneumonia ranging from relatively mild to severe and fatal cases. Children with severe pulmonary compromise are usually more prone to develop BO.  相似文献   
83.
84.
Myoepithelial carcinoma is a rare locally aggressive malignant neoplasm of the salivary glands. The tumor is composed almost exclusively of tumor cells with myoepithelial differentiation and characterized by infiltrative growth and potential for distant metastasis. Tumor cells often display morphologic heterogeneity with a wide range of cytomorphologic features, such as epithelioid, plasmacytoid, spindle, and clear cell types, making its recognition challenging. Only limited reports on its metastatic behavior are available in the literature. We describe a case of metastatic myoepithelial carcinoma of the kidney from the parotid gland diagnosed by computed tomography guided fine‐needle aspiration biopsy. Immunochemical studies are important to confirm myoepithelial differentiation of the tumor cells. Knowledge of the clinical history, radiographic characterization, andmorphological correlation with the primary tumor are emphasized. Diagn. Cytopathol. 2010. © 2009 Wiley‐Liss, Inc.  相似文献   
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86.
An immunochromatographic test for the simultaneous detection of Babesia caballi- and B. equi-specific antibodies (BceICT) was developed using a recombinant B. caballi 48-kDa rhoptry protein (rBc48) and a recombinant truncated B. equi merozoite antigen 2 (rEMA-2t). An evaluation of the ability of the BceICT to detect antibodies in sera from uninfected horses and experimentally infected horses showed high sensitivities and specificities of 83.3% (10/12 sera) and 92.9% (52/56 sera), respectively, for the anti-B. caballi antibody and 94.1% (16/17 sera) and 88.2% (45/51 sera), respectively, for the anti-B. equi antibody. Results from the detection of antibodies in field-collected sera indicated that the BceICT results corresponded with those of enzyme-linked immunosorbent assays (ELISA), showing 91.8% correspondence (67/73 sera) for B. caballi and 95.9% correspondence (70/73 sera) for B. equi, and that the BceICT results also corresponded with the ICT for B. caballi and for B. equi, both of which were 98.2% (55/56 sera). The comparable results of the ICT and ELISA and the simplicity and rapidity of the performance of the ICT suggest that the BceICT would be a feasible test for the simultaneous serodiagnosis of both agents of equine babesiosis in the field.  相似文献   
87.
Human embryonic stem cells have a unique epigenetic signature   总被引:9,自引:1,他引:9       下载免费PDF全文
Human embryonic stem (hES) cells originate during an embryonic period of active epigenetic remodeling. DNA methylation patterns are likely to be critical for their self-renewal and pluripotence. We compared the DNA methylation status of 1536 CpG sites (from 371 genes) in 14 independently isolated hES cell lines with five other cell types: 24 cancer cell lines, four adult stem cell populations, four lymphoblastoid cell lines, five normal human tissues, and an embryonal carcinoma cell line. We found that the DNA methylation profile clearly distinguished the hES cells from all of the other cell types. A subset of 49 CpG sites from 40 genes contributed most to the differences among cell types. Another set of 25 sites from 23 genes distinguished hES cells from normal differentiated cells and can be used as biomarkers to monitor differentiation. Our results indicate that hES cells have a unique epigenetic signature that may contribute to their developmental potential.  相似文献   
88.
89.
Gene expression profiling using microarrays (rat-specific array RG-U34A, Affymetrix, U.S.A.) was employed for the investigation of: (1) hormonal regulation of renal function and (2) nephrotoxicity. For this purpose about 8,800 genes were analysed in kidney and, additionally, in liver tissue.

Ad 1.) Kidney functions develop during postnatal life. Thus, in vivo transport and accumulation of p-aminohippurate (PAH) was investigated on renal cortical slices (RCS) from 10- and 55-day-old rats. The animals were treated with dexamethasone (DEXA; 60 μg/100 g b.wt./day) for 3 days, which caused a significant reduction in the accumulation of PAH in 10-day-old rats (42 ± 5% whereas it was only slightly reduced in 55-day-old rats (70 ± 8%). To further clarify the regulation of renal function by DEXA, results were compared with those obtained previously after in vitro stimulation with DEXA. RCS were incubated for 24 hours in DEXA-containing medium (10−9 M). Under these conditions DEXA significantly increased the PAH uptake capacity in RCS obtained from 10- and 55-day-old rats up to 126 and 136%, respectively. Thus a stimulation of tubular transport capacity is possible in vitro. The effect of DEXA treatment on the gene expression of the kidney (in vivo) was moderate. Focussing especially on transporters, ion channels, ATPases, glucuronyltransferases, glutathione-S-transferase and cytochrome P450, the expression of only few genes were significantly changed (3 to 50-fold up- or down-regulation). Moreover, distinct age differences were found after in vivo administration of DEXA. The investigation of in vitro effects of DEXA is currently been performed.

Ad 2.) The kidney is threatened by nephrotoxins because of its ability to accumulate them. We used a single administration of uranyl nitrate (UN; 0.5 mg/100 g b.wt.) as a model for chronic renal failure (CRF). Clearance experiments were performed 10 weeks after UN administration (maximal symptoms of CRF) in adult female rats. As expected, UN induced interstitial cicatrices with reduced GFR and diminished PAH transport capacity. Despite the impressive morphological and functional changes in the kidney after exposure to UN, the gene expression profiles in the kidneys were only minimally affected: we found significantly changed expression levels for only 20 genes (5 genes were up-regulated [e.g. transgelin], 15 down-regulated [among these the Na-K-Cl-symporter, insulin-like growth factor, kallikrein, and ornithine decarboxylase). The lack of agreement between gene expression data and the nephrotoxic effects of UN can probably be explained by the long time interval between dosing and the assessment of the effect. The results confirm that primary genomic responses are likely to be strongest transiently after exposure and then decrease in intensity.  相似文献   

90.
Diffusion magnetic resonance imaging (MRI) exhibits contrast that identifies macro‐ and microstructural changes in neurodegenerative diseases. Previous studies have shown that MR diffusion tensor imaging (DTI) can observe changes in spinal cord white matter in animals and humans affected with symptomatic amyotrophic lateral sclerosis (ALS). The goal of this preclinical work was to investigate the sensitivity of DTI for the detection of signs of tissue damage before symptoms appear. High‐field MRI data were acquired using a 9.4‐T animal scanner to examine the spinal cord of an ALS mouse model at pre‐ and post‐symptomatic stages (days 80 and 120, respectively). The MRI results were validated using yellow fluorescent protein (YFP) via optical microscopy of spinal cord tissue slices collected from the YFP,G93A‐SOD1 mouse strain. DTI maps of diffusion‐weighted imaging (DWI) signal intensity, mean diffusivity (MD), fractional anisotropy (FA), axial diffusivity (AD) and radial diffusivity (RD) were computed for axial slices of the lumbar region of the spinal cord. Significant changes were observed in FA (6.7% decrease, p < 0.01), AD (19.5% decrease, p < 0.01) and RD (16.1% increase, p < 0.001) at postnatal day 80 (P80). These differences were correlated with changes in axonal fluorescence intensity and membrane cellular markers. This study demonstrates the value of DTI as a potential tool to detect the underlying pathological progression associated with ALS, and may accelerate the discovery of therapeutic strategies for patients with this disease.  相似文献   
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