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21.
M Noureddini J Verdi SA Mortazavi-Tabatabaei S Sharif A Azimi P Keyhanvar A Shoae-Hassani 《Cell biology international》2012,36(10):961-966
The potential of cell therapy is promising in nerve regeneration, but is limited by ethical considerations about the proper and technically safe source of stem cells. We report the successful differentiation of human EnSCs (endometrial stem cells) as a rich source of renewable and safe progenitors into high-efficiency cholinergic neurons. The extracellular signals of NGF (nerve growth factor) and bFGF (basic fibroblast growth factor) could induce cholinergic neuron differentiation. ChAT (choline acetyltransferase), MAP2 (microtubule associated protein 2) and NF-l (neurofilament L) increased after administration of bFGF and NGF to the EnSC cultures. trkC and FGFR2 (fibroblast growth factor receptor 2), which belong to the NGF and bFGF receptors respectively, were determined in populations of EnSCs. NGF, bFGF and their combination differentially influenced human EnSCs high efficiency differentiation. By inducing cholinergic neurons from EnSCs in a chemically defined medium, we could produce human neural cells without resorting to primary culture of neurons. This in vitro method provides an unlimited source of human neural cells and facilitates clinical applications of EnSCs for neurological diseases. 相似文献
22.
T Akerström J Crona A Delgado Verdugo LF Starker K Cupisti HS Willenberg WT Knoefel W Saeger A Feller J Ip P Soon M Anlauf PF Alesina KW Schmid M Decaussin P Levillain B Wängberg JL Peix B Robinson J Zedenius M Bäckdahl S Caramuta KA Iwen J Botling P Stålberg JL Kraimps H Dralle P Hellman S Sidhu G Westin H Lehnert MK Walz G Akerström T Carling M Choi RP Lifton P Björklund 《PloS one》2012,7(7):e41926
Background
Aldosterone producing lesions are a common cause of hypertension, but genetic alterations for tumorigenesis have been unclear. Recently, either of two recurrent somatic missense mutations (G151R or L168R) was found in the potassium channel KCNJ5 gene in aldosterone producing adenomas. These mutations alter the channel selectivity filter and result in Na+ conductance and cell depolarization, stimulating aldosterone production and cell proliferation. Because a similar mutation occurs in a Mendelian form of primary aldosteronism, these mutations appear to be sufficient for cell proliferation and aldosterone production. The prevalence and spectrum of KCNJ5 mutations in different entities of adrenocortical lesions remain to be defined.Materials and Methods
The coding region and flanking intronic segments of KCNJ5 were subjected to Sanger DNA sequencing in 351 aldosterone producing lesions, from patients with primary aldosteronism and 130 other adrenocortical lesions. The specimens had been collected from 10 different worldwide referral centers.Results
G151R or L168R somatic mutations were identified in 47% of aldosterone producing adenomas, each with similar frequency. A previously unreported somatic mutation near the selectivity filter, E145Q, was observed twice. Somatic G151R or L168R mutations were also found in 40% of aldosterone producing adenomas associated with marked hyperplasia, but not in specimens with merely unilateral hyperplasia. Mutations were absent in 130 non-aldosterone secreting lesions. KCNJ5 mutations were overrepresented in aldosterone producing adenomas from female compared to male patients (63 vs. 24%). Males with KCNJ5 mutations were significantly younger than those without (45 vs. 54, respectively; p<0.005) and their APAs with KCNJ5 mutations were larger than those without (27.1 mm vs. 17.1 mm; p<0.005).Discussion
Either of two somatic KCNJ5 mutations are highly prevalent and specific for aldosterone producing lesions. These findings provide new insight into the pathogenesis of primary aldosteronism. 相似文献23.
Desulfurization protein named DszC from Rhodococcus erythropolis is the key enzyme for biodesulforization of dibenzothiophene (DBT) in 4S pathway, which is a pathway with four enzymes. DszC enzyme biodesulfurizes DBT and its derivatives in oil components and biphasic systems. It functions well at the oil- water interface. In this study point mutation performed in DszC enzyme regarding to increase protein hydrophobicity and stability for application in immobilized form. 3D model of DszC predicted using Phyre2, SAM-T08 and M4t servers. I-Mutant 2 server used to determine potential spots for point mutation, and Molegro Virtual Docker (MVD) used for performing point mutation on 3D model. Hydrophobicity plots generated by Bioedit version 7.0.8.0 in Kyte-Doolittle scale indicated that protein hydrophobicity is increased after mutation. Also protein stability increased 26.11 units in scale of DDC2. 相似文献
24.
Miguel ángel Mu?oz-Ruiz P?ivi Hartikainen Juha Koikkalainen Robin Wolz Valtteri Julkunen Eini Niskanen Sanna-Kaisa Herukka Miia Kivipelto Ritva Vanninen Daniel Rueckert Yawu Liu Jyrki L?tj?nen Hilkka Soininen 《PloS one》2012,7(12)
Background
MRI is an important clinical tool for diagnosing dementia-like diseases such as Frontemporal Dementia (FTD). However there is a need to develop more accurate and standardized MRI analysis methods.Objective
To compare FTD with Alzheimer’s Disease (AD) and Mild Cognitive Impairment (MCI) with three automatic MRI analysis methods - Hippocampal Volumetry (HV), Tensor-based Morphometry (TBM) and Voxel-based Morphometry (VBM), in specific regions of interest in order to determine the highest classification accuracy.Methods
Thirty-seven patients with FTD, 46 patients with AD, 26 control subjects, 16 patients with progressive MCI (PMCI) and 48 patients with stable MCI (SMCI) were examined with HV, TBM for shape change, and VBM for gray matter density. We calculated the Correct Classification Rate (CCR), sensitivity (SS) and specificity (SP) between the study groups.Results
We found unequivocal results differentiating controls from FTD with HV (hippocampus left side) (CCR = 0.83; SS = 0.84; SP = 0.80), with TBM (hippocampus and amygdala (CCR = 0.80/SS = 0.71/SP = 0.94), and with VBM (all the regions studied, especially in lateral ventricle frontal horn, central part and occipital horn) (CCR = 0.87/SS = 0.81/SP = 0.96). VBM achieved the highest accuracy in differentiating AD and FTD (CCR = 0.72/SS = 0.67/SP = 0.76), particularly in lateral ventricle (frontal horn, central part and occipital horn) (CCR = 0.73), whereas TBM in superior frontal gyrus also achieved a high accuracy (CCR = 0.71/SS = 0.68/SP = 0.73). TBM resulted in low accuracy (CCR = 0.62) in the differentiation of AD from FTD using all regions of interest, with similar results for HV (CCR = 0.55).Conclusion
Hippocampal atrophy is present not only in AD but also in FTD. Of the methods used, VBM achieved the highest accuracy in its ability to differentiate between FTD and AD. 相似文献25.
Newborn mammals, compared to adults, are extremely resistant to the CNS effects of hyperbaric oxygenation (HBO) induced by excessive generation of reactive oxygen species. This tolerance to HBO may be related to either physiological responses or the chemical characteristics of the immature brain, including a low cerebral blood flow and energy metabolism and a low concentration of polyunsaturated fatty acids. In adult mammals the main protective mechanism against CNS oxygen toxicity, besides endogenous antioxidants, is a transient HBO-induced cerebral vasoconstriction. How cerebral vasculature reacts to HBO in the immature brain is not known. We present indirect evidence suggesting that HBO in newborn rats induces a persistent cerebral vasoconstriction concurrently with a severe and maintained reduction in ventilation. It is speculated that the outcome of these physiologic responses to hyperoxic exposures may be: (a) extension of tolerance to both CNS and pulmonary oxygen poisoning; (b) creation of a profound hypoxic-ischemic condition in vulnerable neural structures: and (c) impairement of the circulatory and ventilatory responses to hypoxic stimuli on return to air consequent development of a secondary hypoxic-ischemic condition. These hypothetical pre- and post-HBO events may set the stage for the development of some delayed neurological disorders, including the retinopathy of prematurity and the retardation of brain development in fetuses or prematurely-born infants subjected to oxygen therapy. 相似文献
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28.
Emad Sanati Farvash Saeid Gitipour Peyman Yaghoobzadeh Reza Maleki Delarestaghi 《人类与生态风险评估》2016,22(6):1289-1300
In this research, carcinogenic and non-carcinogenic human health risks due to polycyclic aromatic hydrocarbons (PAHs) were investigated via three exposure pathways: accidental ingestion of soil, dermal contact of soils, and contaminated vegetable ingestion. To determine the contaminant concentrations in soil, samples were collected from areas adjacent to the Tehran oil refinery, located in Shahr-e-Ray city, Iran. Analyses of the samples indicated that the average of PAHs concentration in the soil samples were greater than clean-up level guidelines. Cancer risk of contaminants due to ingestion of cultivated vegetables that are sold in Tehran markets was significant in comparison with other exposure pathways. Moreover, the total cancer risk for 5th percentile, 95 upper confidence limit, and 95th percentile concentration of contaminants were 5.69E-04, 8.78E-02, and 2.13E-01, classifying the site as having a significant cancer risk potential. Furthermore, non-carcinogenic health risk analyses for the contaminants demonstrated hazard index of less than 1. Remediation of the soils is highly recommended to eliminate the potential cancer risks and prevent the contamination of the food chain for approximately 10 million Tehran residents. 相似文献
29.
Maryam Ebrahim-Ghomi Bagher Mahmoodi Farshad Rakhshanderoo Masoud Naderpour Peyman Norouzi 《Archives Of Phytopathology And Plant Protection》2016,49(1-4):1-10
Beet necrotic yellow vein virus (BNYVV) is the most devastating pathogen of sugar beet worldwide. This virus has been reported in the majority of sugar beet growing regions of Iran as well. For the present study, we collected samples from different sugar beet varieties with suspected symptoms of BNYVV from the main important sugar beet growing regions in eight provinces of Iran. Infection of collected samples to BNYVV was tested by ELISA and RT-PCR. Upon testing of 167 collected samples of BNYVV suspected through ELISA and RT-PCR, 115 (68.9%) were infected. Different incidences of BNYVV through surveyed provinces may represent the presence of diverse infective viral sources or resistance genes in tested sugar beet varieties which need further attempts to develop control strategies. Results also showed that BNYVV has been recently distributed throughout some surveyed regions. Otherwise, trace infection or resistance to BNYVV infection in some varieties of distinct regions may represent proper sources of resistance to BNYVV. 相似文献
30.
Solis M Nakhaei P Jalalirad M Lacoste J Douville R Arguello M Zhao T Laughrea M Wainberg MA Hiscott J 《Journal of virology》2011,85(3):1224-1236
The rapid induction of type I interferon (IFN) is essential for establishing innate antiviral responses. During infection, cytoplasmic viral RNA is sensed by two DExD/H box RNA helicases, RIG-I and MDA5, ultimately driving IFN production. Here, we demonstrate that purified genomic RNA from HIV-1 induces a RIG-I-dependent type I IFN response. Both the dimeric and monomeric forms of HIV-1 were sensed by RIG-I, but not MDA5, with monomeric RNA, usually found in defective HIV-1 particles, acting as a better inducer of IFN than dimeric RNA. However, despite the presence of HIV-1 RNA in the de novo infection of monocyte-derived macrophages, HIV-1 replication did not lead to a substantial induction of IFN signaling. We demonstrate the existence of an evasion mechanism based on the inhibition of the RIG-I sensor through the action of the HIV-1 protease (PR). Indeed, the ectopic expression of PR resulted in the inhibition of IFN regulatory factor 3 (IRF-3) phosphorylation and decreased expression of IFN and interferon-stimulated genes. A downregulation of cytoplasmic RIG-I levels occurred in cells undergoing a single-cycle infection with wild-type provirus BH10 but not in cells transfected with a protease-deficient provirus, BH10-PR(-). Cellular fractionation and confocal microscopy studies revealed that RIG-I translocated from the cytosol to an insoluble fraction during the de novo HIV-1 infection of monocyte-derived macrophages, in the presence of PR. The loss of cytoplasmic RIG-I was prevented by the lysosomal inhibitor E64, suggesting that PR targets RIG-I to the lysosomes. This study reveals a novel PR-dependent mechanism employed by HIV-1 to counteract the early IFN response to viral RNA in infected cells. 相似文献