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21.
Bahareh Eftekharzadeh Javad Hamedi Fatemeh Mohammadipanah Fariba Khodagholi Nader Maghsoudi Hans Peter Klenk 《Applied microbiology and biotechnology》2010,86(6):1805-1811
Actinomycetes isolated from Iran soil habitats were tested for the capacity to produce compounds which can protect neurons
from cell death generated by oxidative stress in NT2 neurons. Confirmation of our initial hit was accomplished via the determination
of amyloid β level using the enzyme-linked immunosorbent assay test. The most interesting amyloid β formation inhibitor discovered
in our study was a secondary metabolite which was produced by strain HM45. This bioactive strain was identified as a strain
of Streptomyces antibioticus DSM 40234 using polyphasic approach. The strain HM45 was deposited in Deutsche Sammlung von Mikroorganismen und Zellkulturen
as S. antibioticus DSM 41955 and University of Tehran Microorganisms Sollection as S. antibioticus UTMC 00105. This work is the first report on efficiency of an actinomycete metabolite in prohibition of neurons death caused
by amyloid β formation. 相似文献
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23.
Bahrami G Mirzaeei S Kiani A Mohammadi B 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2005,823(2):213-217
A simple, fast, and sensitive high performance liquid chromatographic (HPLC) assay was developed for quantitation of lamivudine in human serum. Lamivudine is polar compound and its extraction from the human serum in previously published HPLC methods involved either protein precipitation or solid phase extraction techniques. However, existence of endogenous peaks which interfere with the drug or appeared as late eluting peaks and lead to long run time of analysis has been reported. Application of either an ion pairing agent in the mobile phase or time consuming column purge has been used in the published methods. Present paper describes liquid - liquid extraction of lamivudine and internal standard (famotidine) using dichloromethane-isopropyl alcohol (1:1, v/v) as an extracting solvent and salting out approach. The mobile phase was a mixture of phosphate buffer (0.05 M) containing triethylamine (1 mL/L, v/v; pH 3.5) and methanol (91:9, v/v) at a flow rate of 2.2 mL/min. The analysis was performed on a column (150 mm x 6 mm i.d.) which was packed with 5 microm particles of ODS packing material. Under these conditions no interference in the assay from any endogenous substance was observed. The limit of quantification was evaluated to be 5 ng/mL. Accuracy and precision of the method were also studied and the technique was shown to be selective and linear into the concentration range of 5-2500 ng/mL. This method has been used in two randomized crossover bioequivalence studies of 100 and 150 mg lamivudine preparations in 12 and 24 healthy volunteers, respectively. 相似文献
24.
Mohammad Panahi Bahareh Rahimi Golbarg Rahimi Teck Yew Low Neda Saraygord-Afshari Effat Alizadeh 《Journal of cellular physiology》2020,235(10):6462-6495
Mesenchymal stem cells (MSCs) are earmarked as perfect candidates for cell therapy and tissue engineering due to their capacity to differentiate into different cell types. However, their potential for application in regenerative medicine declines when the levels of the reactive oxygen and nitrogen species (RONS) increase from the physiological levels, a phenomenon which is at least inevitable in ex vivo cultures and air-exposed damaged tissues. Increased levels of RONS can alter the patterns of osteogenic and adipogenic differentiation and inhibit proliferation, as well. Besides, oxidative stress enhances senescence and cell death, thus lowering the success rates of the MSC engraftment. Hence, in this review, we have selected some representatives of antioxidants and newly emerged nano antioxidants in three main categories, including chemical compounds, biometabolites, and protein precursors/proteins, which are proved to be effective in the treatment of MSCs. We will focus on how antioxidants can be applied to optimize the clinical usage of the MSCs and their associated signaling pathways. We have also reviewed several paralleled properties of some antioxidants and nano antioxidants which can be simultaneously used in real-time imaging, scaffolding techniques, and other applications in addition to their primary antioxidative function. 相似文献
25.
Purpose
To investigate presence, location and functional role of calcium-activated chloride channel (CaCC) Anoctamin-1 (Ano1) in rat urinary bladder.Materials and Methods
Bladders from 3 week old Wistar rats were studied. End-point PCR on total mRNA was used to assess the expression of Ano1. Immunofluorescent labelling of whole mount bladder tissue imaged with confocal microscope allowed localization of Ano1 and vimentin immunopositive cells. The effects of CaCC blockers: niflumic acid (NFA) (3,10,30 µM) and 5-Nitro-2-(3-phenylpropylamino)benzoic acid (NPPB) (10, 30 µM) on spontaneous phasic contractile activity of intact (with mucosa) and denuded (without mucosa) detrusor strips were measured under isometric tension in organ baths (n = 141, N = 60).Results
Ano1 expression was found at mRNA level in mucosa and detrusor layers. Confocal microscopy revealed presence of Ano1 immunopositive cells in mucosa and in detrusor layers; a subpopulation of vimentin positive cells expressed Ano1. Both chloride channel blockers reduced the amplitude and frequency of phasic contractions in denuded and intact strips.Conclusions
Ano1 is expressed in rat urinary bladder and is present in cells sharing markers with interstitial cells. CaCC blockers reduced phasic activity of the bladder tissue. Ano1 is expressed in the bladder and plays a role in its spontaneous phasic contractile activity. 相似文献26.
27.
Nafiseh Yousefi Abdolkarim Chehregani Behrouz Malayeri Bahareh Lorestani Mehrdad Cheraghi 《Biological trace element research》2011,140(3):368-376
Excessive amounts of heavy metals adversely affect plant growth and development. Whereas some regions naturally contain high
levels of heavy metals, anthropogenic release of heavy metals into the environment continuously increases soil contamination.
Preliminary studies have shown that Chenopodium botrys can grow in some heavy metal contaminated soils and is a high accumulator plant species for Cu and moderately accumulator
plant species for Fe, Mn, and Zn, thus, was considered as an important species in this study. Based on that, in this species,
we studied the individual effects of heavy metals on the formation, development, and structure of anther and pollen. To achieve
this purpose, surrounding area of Hame-Kasi iron and copper mine (Hamedan, Iran) was chosen as a polluted area where the amount
of some heavy metals was several times higher than the natural soils. Flowers and young pods were removed from non-polluted
and polluted plants, fixed in FAA 70, and subjected to developmental studies. Analysis of anther development in plants from
contaminated sites showed general similarities in the pattern of pollen formation with those from non-polluted ones, but also
deviation from typical form of major stages of anther and pollen development was seen in plants from polluted ones. Stabilizing
of tapetum layer, increasing in tapetum layer numbers, thickening callose wall in the microspore mother cell stage, changing
the anther shape, and decreasing the size of anther were the effects of heavy metals. Reduction of pollen number was also
seen in the plants collected from polluted area. 相似文献
28.
Bahareh Bahmani Mehryar Habibi Roudkenar Raheleh Halabian Ali Jahanian-Najafabadi Fatemeh Amiri Mohammad Ali Jalili 《Cell stress & chaperones》2014,19(5):685-693
The regenerative potential of mesenchymal stem cells (MSCs) is impaired by cellular senescence, a multi factorial process that has various functions. However, pathways and molecules involved in senescence have not been fully identified. Lipocalin 2 (Lcn2) has been the subject of intensive research, due to its contribution to many physiological and pathophysiological conditions. The implication of Lcn2 has been reported in many conditions where senescence also occurs. In the present study, we evaluated the role of Lcn2 in the occurrence of senescence in human bone marrow-derived mesenchymal stem cells (hB-MSCs) under oxidative conditions. When hB-MSCs were genetically engineered to over-express Lcn2 (MSC-Lcn2) and exposed to H2O2, the proliferation rate of the cells increased. However, the number of colonies and the number of cells that made up each colony in both MSC-V and MSC-Lcn2 cells decreased compared to those cultivated under normal conditions. Our results revealed that over-expression of recombinant Lcn2 in hB-MSCs decreases senescence induced by H2O2 treatment. Senescent cells were observed in aged hB-MSCs; however, no alteration in the expression level of Lcn2 was detected compared to earlier passages. Finally, a higher amount of Lcn2 protein was detected in the plasma of the elderly than in young people. Our findings suggest that Lcn2 might restore the health and regeneration potential of MSCs by decreasing senescence. 相似文献
29.
Oddo S Caccamo A Cheng D Jouleh B Torp R LaFerla FM 《Journal of neurochemistry》2007,102(4):1053-1063
The two hallmark pathologies of Alzheimer's disease (AD) are amyloid plaques, composed of the small amyloid-beta (Abeta) peptide, and neurofibrillary tangles, comprised aggregates of the microtubule binding protein, tau. The molecular linkage between these two lesions, however, remains unknown. Based on human and mouse studies, it is clear that the development of Abeta pathology can trigger tau pathology, either directly or indirectly. However, it remains to be established if the interaction between Abeta and tau is bidirectional and whether the modulation of tau will influence Abeta pathology. To address this question, we used the 3xTg-AD mouse model, which is characterized by the age-dependent buildup of both plaques and tangles. Here we show that genetically augmenting tau levels and hyperphosphorylation in the 3xTg-AD mice has no effect on the onset and progression of Abeta pathology. These data suggest that the link between Abeta and tau is predominantly if not exclusively unidirectional, which is consistent with the Abeta cascade hypothesis and may explain why tauopathy-only disorders are devoid of any Abeta pathology. 相似文献
30.
Nasri Elahe Shoaei Parisa Vakili Bahareh Mirhendi Hossein Sadeghi Somayeh Hajiahmadi Somayeh Sadeghi Alireza Vaezi Afsane Badali Hamid Fakhim Hamed 《Mycopathologia》2020,185(6):1077-1084
Mycopathologia - Although patients with severe immunodeficiency and hematological malignancies has been considered at highest risk for invasive fungal infection, patients with severe pneumonia due... 相似文献