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41.
Bakhshalizadeh S Esmaeili F Houshmand F Shirzad H Saedi M 《In vitro cellular & developmental biology. Animal》2011,47(8):550-557
Selegiline, the irreversible inhibitor of monoamine oxidase B (MAO-B), is currently used to treat Parkinson’s disease. However,
the mechanism of action of selegiline is complex and cannot be explained solely by its MAO-B inhibitory action. It stimulates
gene expression, as well as expression of a number of mRNAs or proteins in nerve and glial cells. Direct neuroprotective and
anti-apoptotic actions of selegiline have previously been observed in vitro. Previous studies showed that selegiline can induce
neuronal phenotype in cultured bone marrow stem cells and embryonic stem cells. Embryonal carcinoma (EC) cells are developmentaly
pluripotene cells which can be differentiated into all cell types under the appropriate conditions. The present study was
carried out to examine the effects of selegiline on undifferentiated P19 EC cells. The results showed that selegiline treatment
had a dramatic effect on neuronal morphology. It induced the differentiation of EC cells into neuron-like cells in a concentration-dependent
manner. The peak response was in a dose of selegiline significantly lower than required for MAO-B inhibition. The differentiated
cells were immunoreactive for neuron-specific proteins, synaptophysin, and β-III tubulin. Stem cell therapy has been considered
as an ideal option for the treatment of neurodegenerative diseases. Generation of neurons from stem cells could serve as a
source for potential cell therapy. This study suggests the potential use of combined selegiline and stem cell therapy to improve
deficits in neurodegenerative diseases. 相似文献
42.
Taheri F Nematzadeh G Zamharir MG Nekouei MK Naghavi M Mardi M Salekdeh GH 《Molecular bioSystems》2011,7(11):3028-3035
"Candidatus Phytoplasma aurantifolia" is the causative agent of witches' broom disease in the Mexican lime tree (Citrus aurantifolia L.), and is responsible for major tree losses in Southern Iran and Oman. The pathogen is strictly biotrophic, and, therefore, completely dependent on living host cells for its survival. The molecular basis of compatibility and disease development in this system is poorly understood. We applied a proteomics approach to analyse gene expression in Mexican limes infected with "Ca. Phytoplasma aurantifolia". Leaf samples were collected from healthy and infected plants and were analysed using 2-DE coupled with MS. Among 800 leaf proteins that were detected reproducibly in eight biological replicates of healthy and eight biological replicates of infected plants, 55 showed a significant response to the disease. MS resulted in identification of 39 regulated proteins, which included proteins that were involved in oxidative stress defence, photosynthesis, metabolism, and the stress response. Our results provide the first proteomic view of the molecular basis of the infection process and identify genes that could help inhibit the effects of the pathogen. 相似文献
43.
Mojtaba Sankian Abdolreza Varasteh Nazanin Pazouki Mahmoud Mahmoudi 《Clinical and molecular allergy : CMA》2005,3(1):1-9
Background
The basophil activation test (BAT), in which translocation of markers to the surface of blood basophils is measured in response to allergen by flow cytometry, is a rapid assay that is gaining popularity. Two markers are currently being evaluated for the BAT; CD63 and the lineage-specific CD203c. In a recent report, detection of CD203c after lysis with Saponin was shown to be superior to detection of CD63 after lysis with formic acid. We wanted to compare a) lysis with formic acid and lysis with Saponin, b) the response through CD203c and CD63, and c) the definition 10% activated cells above background with the probability binning metric T(χ) > 4, on sets of data generated with blood basophils stimulated with varying concentrations of anti-FcεRI antibody.Methods
Blood from volunteers was incubated with serial logarithmic dilutions of anti-FcεRI and subsequently with antibodies to CD203c PE and CD63 FITC. Sets of samples set up in parallel were lysed with either Saponin based Whole Blood Lysing reagent or with formic acid based Immunoprep/Q-prep. Samples were acquired on a FACS Calibur, but were compensated and analysed offline. Responders were defined as persons who had 10% or more activated basophils above background, or a T(χ) > 4, for two consecutive dilutions of anti-FcεRI antibody.Results
More basophils (median 1164 vs. median 397) and better discrimination of upregulated CD203c and CD63 amongst responders were obtained after lysis with Saponin than after lysis with formic acid. We suggest that CD203c may be a more sensitive marker for the BAT than CD63, as 6/11 responders were found with CD203c, compared with 3/11 with CD63. Most responders (7/11) were identified with probability binning.Conclusion
A combination of lysis with Saponin and the markers CD203c and CD63 computed by probability binning may be the most sensitive method of detecting activation of basophils after stimulation through FcεRI. 相似文献44.
Background
Detecting a QTL is only the first step in genetic improvement programs. When a QTL with desirable characteristics is found, e.g. in a wild or unimproved population, it may be interesting to introgress the detected QTL into the commercial population. One approach to shorten the time needed for introgression is to combine both QTL identification and introgression, into a single step. This combines the strengths of fine mapping and backcrossing and paves the way for introgression of desirable but unknown QTL into recipient animal and plant lines.Methods
The method consisting in combining QTL mapping and gene introgression has been extended from inbred to outbred populations in which QTL allele frequencies vary both in recipient and donor lines in different scenarios and for which polygenic effects are included in order to model background genes. The effectiveness of the combined QTL detection and introgression procedure was evaluated by simulation through four backcross generations.Results
The allele substitution effect is underestimated when the favourable QTL allele is not fixed in the donor line. This underestimation is proportional to the frequency differences of the favourable QTL allele between the lines. In most scenarios, the estimates of the QTL location are unbiased and accurate. The retained donor chromosome segment and linkage drag are similar to expected values from other published studies.Conclusions
In general, our results show that it is possible to combine QTL detection and introgression even in outbred species. Separating QTL mapping and introgression processes is often thought to be longer and more costly. However, using a combined process saves at least one generation. With respect to the linkage drag and obligatory drag, the results of the combined detection and introgression scheme are very similar to those of traditional introgression schemes. 相似文献45.
Rainbow trout Oncorhynchus mykiss Walbaum, 1792 fingerlings were vaccinated by intraperitoneal (i.p.) injection using live theronts of the skin parasitic ciliate Ichthyophthirius multifiliis Fouquet, 1876 at 2 temperatures (12 and 20 degrees C), and protection against challenge infections was subsequently evaluated by bath exposure to live theronts. Vaccination conferred a relative protection (evaluated as the decrease in the number of established theronts) at 12 degrees C and almost complete immunity at 20 degrees C. Significantly increased immobilisation titers (using plasma immobilisation of live theronts) were found in immunised fish at Week 2 and 4 post-vaccination. Lysozyme activity of plasma from vaccinated fish increased from Week 1 to 4. Both immobilisation titers and lysozyme activity were significantly higher at 20 degrees C. This study demonstrated that live theronts are good candidates for an antigen source for development of effective vaccines against white spot disease in this fish host, and further indicated that the protection of rainbow trout against I. multifiliis infection is highly temperature dependent and may be associated with both adaptive and innate response mechanisms. 相似文献
46.
Hosseini Tafreshi SA Shariati M Mofid MR Khayam Nekui M Esmaeili A 《Molecular biology reports》2012,39(3):2169-2178
VIGS (virus induced gene silencing) is considered as a powerful genomics tool for characterizing the function of genes in
a few closely related plant species. The investigations have been carried out mainly in order to test if a pre-existing VIGS
vector can serve as an efficient tool for gene silencing in a diverse array of plant species. Another route of investigation
has been the constructing of new viral vectors to act in their hosts. Our approach was the creation of a heterologous system
in which silencing of endogenous genes was achieved by sequences isolated from evolutionary remote species. In this study,
we showed that a TRV-based vector cloned with sequences from a gymnosperm, Taxus baccata L. silenced the endogenous phytoene desaturase in an angiosperm, N. benthamiana. Our results showed that inserts of between 390 and 724 bp isolated from a conserved fragment of the Taxus PDS led to silencing of its homolog in tobacco. The real time analysis indicated that the expression of PDS was reduced 2.1- to 4.0-fold in pTRV-TbPDS infected plants compared with buffer treated plants. Once the best insert is identified and the conditions are optimized
for heterologous silencing by pTRV-TbPDS in tobacco, then we can test if TRV can serve as an efficient silencing vector in Taxus. This strategy could also be used to silence a diverse array of genes from a wide range of species which have no VIGS protocol.
The results also showed that plants silenced heterologously by the VIGS system a minimally affected with respect to plant
growth which may be ideal for studying the genes that their complete loss of function may lead to decrease of plant growth
or plant death. 相似文献
47.
48.
Mojtaba Sankian Fatemeh Vahedi Nazanin Pazouki Malihe Moghadam Farahzad Jabbari Azad Abdol-Reza Varasteh 《Reports of Biochemistry & Molecular Biology》2012,1(1):25-29
Background:
Allergy is a clinical disorder affecting the human population with wide geographical distribution. Platanus orientalis (P. orientalis) trees are planted in many countries and their pollen causes allergic reactions.Cyclophilin has recently been identified as one of the most important allergens of P. orientalis pollen. We aimed to clone and purify this allergen in Escherichia coli for further studies and therapeutic and diagnostic purposes for allergy to P. orientalis.Methods:
RNA was extracted from P. orientalis. A full-length fragment encoding cyclophilin was prepared by polymerase chain reaction amplification of the first-strand cDNA synthesized from P. orientalis RNA. The cDNA was inserted into the pET32b (+) vector, and the construct transformed into E. coli Top10 and BL21 cells. The expressed protein was purified by the CuSO4 method.Results:
The cDNA for the cyclophilin of P. orientalis pollen was cloned, and a specific reactivity of recombinant cyclophin was confirmed by immunoblotting using sera from patients allergic to P. orientalis pollen.Conclusion:
The recombinant cyclophilin has a potential for immunologic assays for evaluation of allergy to P. orientalis pollen.Key Words: Allergy; Recombinant allergen; Cyclophilin, Escherichia coli, Platanus orientalis, Pollen, Cloning 相似文献49.
50.
Ebrahimi B Valojerdi MR Eftekhari-Yazdi P Baharvand H 《Zygote (Cambridge, England)》2012,20(2):103-115
To determine the ultrastructural changes of sheep cumulus-oocyte complexes (COCs) following different methods of vitrification, good quality isolated COCs (GV stage) were randomly divided into the non-vitrified control, conventional straw, cryotop and solid surface vitrification groups. In both conventional and cryotop methods, vitrified COCs were respectively loaded by conventional straws and cryotops, and then plunged directly into liquid nitrogen (LN2); whereas in the solid surface group, vitrified COCs were first loaded by cryotops and then cooled before plunging into LN2. Post-warming survivability and ultrastructural changes of healthy COCs in the cryotop group especially in comparison with the conventional group revealed better viability rate and good preservation of the ooplasm organization. However in all vitrification groups except the cryotop group, mitochondria were clumped. Solely in the conventional straw group, the mitochondria showed different densities and were extremely distended. Moreover in the latter group, plenty of large irregular connected vesicles in the ooplasm were observed and in some parts their membrane ruptured. Also, in the conventional and solid surface vitrification groups, cumulus cells projections became retracted from the zona pellucida in some parts. In conclusion, the cryotop vitrification method as compared with other methods seems to have a good post-warming survivability and shows less deleterious effects on the ultrastructure of healthy vitrified-warmed sheep COCs. 相似文献