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61.
Abolghasem Abbasi Kejani Sayed Ali Hosseini Tafreshi Sayed Mojtaba Khayyam Nekouei Mohammad Reza Mofid 《Molecular biology reports》2010,37(2):797-800
Improved and efficient methods were developed for isolating high quality DNA and RNA from different sources of Iranian Yew
(Taxus baccata L.). The methods were based on CTAB extraction buffer added with high levels of polyvinylpyrrolidone (PVP) and β-mercaptoethanol to properly remove polysaccharides and prevent oxidation of phenolics. The pellets obtained by ethanol precipitation
were washed only with Chloroform: isoamyl alcohol (24:1). So, we could successfully eliminate the dangerous phenol/chloroform
extraction steps from the isolation procedure. Both spectrophotometric (A260/A280 and A260/A230 ratios) and agarose electrophoresis analysis of isolated nucleic acids (DNA and RNA) indicated good results. DNA with the
average yield of 100–300 μg/g leaf and stem tissue and total RNA with an average yield of 20–30 μg/g cell culture and 80–100 μg/g
leaf and stem tissue of Iranian yew could be obtained. Successful amplification of pam and pds by PCR and RT-PCR, showed the integrity of isolated DNA and RNA, respectively. 相似文献
62.
Hamed R. Goodarzi Ali Abbasi Mojtaba Saffari Mohammad B. Tabei Mohammad R. Noori Daloii 《Molecular biology reports》2010,37(6):2959-2965
Male Pattern Baldness (MPB) or androgenetic alopecia is a common form of hair loss with androgens and genetics having etiological
significance. Androgens are thought to pathophysiologically power on cascades of chronically dramatic alterations in genetically
susceptible scalp dermal papillas, specialized cells in hair follicles in which androgens react, and finally resulting in
a patterned alopecia. However, the exact mechanisms through which androgens, positive regulators of growth and anabolism in
most body sites, paradoxically exert their effects on balding hair follicles, are not yet known. The role of microRNAs, a
recently discovered class of non-coding RNAs, with a wide range of regulatory functions, has been documented in hair follicle
formation and their deregulation in cancer of prostate, a target organ of androgens has also been delineated. Yet, there is a lack of knowledge in agreement with microRNAs’ contribution in pathophysiology of MPB. To investigate the
role of microRNAs in pathogenesis of MPB, we selected seven microRNAs, predicted bioinformatically on a reverse engineering
basis, from previously published microarray gene expression data and analyzed their expression in balding relative to non-balding
dermal papillas. We found for the first time upregulation of four microRNAs (miR-221, miR-125b, miR-106b and miR-410) that
could participate in pathogenesis of MPB. Regarding microRNAs’ therapeutic potential and accessibility of hair follicles for
gene therapy, these microRNAs can be considered as good candidates for a new revolutionized generation of treatments. 相似文献
63.
64.
M. A. Latif Mohd Yosuh Omar Soon Guan Tan S.S. Siraj Abdul Rahim Ismail 《Insect Science》2010,17(6):517-526
Abstract Two sympatric populations of brown planthopper (BPH), one from rice and the other from Leersia hexandra were collected from each of five locations in Malaysia. All the tested malathion-resistant individuals of the rice BPH population and F1 generation (cross between malathion-resistant [usually caught on rice] and malathion-susceptible [usually caught on Leersia]) showed high esterase activity, while all malathion-susceptible individuals on L. hexandra showed low esterase activity. In the F2 generation, all the individuals tested against malathion were approximately 75% resistant and 25% susceptible and the inheritance pattern of esterase activity (high and low esterase activity) segregated in the same manner to a 3: 1 ratio. This confirms that resistance to malathion is mono-factorial and inheritance pattern of esterase activity is also linked to malathion resistance. Carboxylesterase or total esterase activity in BPH is inherited in a simple Mendelian fashion that is encoded by a single dominant gene. For the total esterase assay, average esterase activity levels in the rice-infesting population ranged from 17.64 to 19.37 nmoles 1-napthol/mg protein while that in the Leersia-infesting population ranged from 5.29 to 6.11 nmoles 1-napthol/mg protein. In terms of esterase activity, the two sympatric Nilaparvata lugens populations separated into two distinct groups. Results based on the tube color intensity test showed 96% and 98% resistant and susceptible individuals were present in the rice- and Leersia-infesting populations, respectively. In a filter paper test, the rice-infesting population had 94% with high esterase activity while the Leersia-infesting population had 96% with low esterase activity. 相似文献
65.
66.
Azalina Zainuddin Kien Hui Chua Norhazira Abdul Rahim Suzana Makpol 《BMC molecular biology》2010,11(1):59
Background
Several genes have been used as housekeeping genes and choosing an appropriate reference gene is important for accurate quantitative RNA expression in real time RT-PCR technique. The expression levels of reference genes should remain constant between the cells of different tissues and under different experimental conditions. The purpose of this study was to determine the effect of different experimental treatments on the expression of glyceraldehyde 3-phosphate dehydrogenase (GAPDH) mRNA so that the reliability of GAPDH as reference gene for quantitative real time RT-PCR in human diploid fibroblasts (HDFs) can be validated. HDFs in 4 different treatment groups viz; young (passage 4), senescent (passage 30), H2O2-induced oxidative stress and γ-tocotrienol (GTT)-treated groups were harvested for total RNA extraction. Total RNA concentration and purity were determined prior to GAPDH mRNA quantification. Standard curve of GAPDH expression in serial diluted total RNA, melting curve analysis and agarose gel electrophoresis were used to determine the reliability of GAPDH as reference gene. 相似文献67.
68.
Oxidative aromatization of 4-alkyl or aryl and heterocyclic-substituted derivatives of Hantzsch 1,4-dihydropyridines to the corresponding pyridine derivatives has been studied using benzyltriphenylphosphonium peroxymonosulfate as an oxidant in the presence of BiCl(3) under nearly neutral reaction conditions at ambient temperature. 相似文献
69.
Axonal guidance signals are transduced through growth cone surface receptors to the interior leading to changes of actin dynamics
and actin binding proteins, which are critical in determining the outcome of actin cytoskeleton reorganization. We report
here the characterization of the Drosophila actin binding protein abLIM/Unc-115 homolog Dunc-115 and its role in the nervous system. Three Dunc-115 isoforms are identified
as Dunc-115L, M and S, respectively. While Dunc-115L is a canonical homolog of Unc-115 with four LIM domains and one villin
headpiece domain, Dunc-115M and S are novel isoforms without counterparts in other species. Our molecular modeling shows Dunc-115L
is likely to bind to actin. Mutant analysis reveals that Dunc-115 is involved in axonal projection in both the visual and
central nervous system. 相似文献
70.