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21.
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
22.
Shakibaie M Forootanfar H Mollazadeh-Moghaddam K Bagherzadeh Z Nafissi-Varcheh N Shahverdi AR Faramarzi MA 《Biotechnology and applied biochemistry》2010,57(2):71-75
The application of green-synthesis principles is one of the most impressive research fields for the production of nanoparticles. Different kinds of biological systems have been used for this purpose. In the present study, AuNPs (gold nanoparticles) were prepared within a short time period using a fresh cell extract of the marine microalga Tetraselmis suecica as a reducing agent of HAuCl4 (chloroauric acid) solution. The UV-visible spectrum of the aqueous medium containing AuNPs indicated a peak at 530 nm, corresponding to the surface plasmon absorbance of AuNPs. The X-ray diffraction pattern also showed a Bragg reflection related to AuNPs. Fourier-transform infrared spectroscopy was performed for analysis of surface functional groups of AuNPs. Transmission electron microscopy and particle-size-distribution patterns determined by the laser-light-scattering method confirmed the formation of well-dispersed AuNPs. The most frequent size of particles was 79 nm. 相似文献
23.
An experiment was conducted to determine the effect of dietary vitamin E and C on serum metabolites, yolk cholesterol, egg quality, and performance of layer hens. One hundred sixty-eight commercial Hy-Line W-36 layer hens were randomly divided into seven groups and six replicates with four hens in each. Dietary treatments were introduced after the pre-experimental period (10 days) to adjust egg production. Treatments were levels of vitamin E or C (100, 200, and 400 mg/kg diet) supplementation to the basal diet for 4 weeks, whereas the control group received no supplementation. Egg production, egg weight, and feed consumption were recorded during the study. Shell thickness, Haugh unit score, yolk color, yolk weight, yolk cholesterol, and blood parameters were measured at the end of experiment. There was no significant effect of dietary vitamin E or C on hen performance. Egg yolk cholesterol concentrations decreased linearly by antioxidant vitamin supplementation (P?<?0.01). Egg yolk cholesterol reduction did not have any negative effect on egg production rate. Antioxidants, especially vitamin C, increased serum glucose concentration (P?<?0.05). Serum total cholesterol content did not change by vitamin supplementation but cholesterol in high-density lipoprotein (HDL-C) decreased and cholesterol in low-density lipoprotein (LDL-C) increased (P?<?0.05), as dietary vitamin E or C supplementation increased in diets. These results are in conflict with the previous hypothesis that antioxidants have a role in LDL-C removal from the blood or increasing HDL-C. Vitamin E was more effective than vitamin C in this case and if these results are confirmed by further studies, they may result to revision in researchers’ point of view about antioxidant especially in human medicine. 相似文献
24.
Mojtaba Amiri Leila Farzin Mohammad Esmail Moassesi Fattaneh Sajadi 《Biological trace element research》2010,135(1-3):38-44
Febrile convulsion is the most common disorder in childhood with good prognosis. There are different hypotheses about neurotransmitters and trace element changes in biological fluids which can have a role in pathogenesis of febrile convulsion. In this study, serum selenium, zinc, and copper were measured by atomic absorption spectrometry in the children with febrile convulsion (n?=?30) and in the control group (n?=?30). The age and sex of the subjects were registered. Selenium and zinc were found to be significantly lower in febrile convulsion cases than in the control group (p?<?0.0001 and p?<?0.0001, respectively). There was no significant difference in the value of copper between the two groups (p?=?0.16). While selenium and zinc levels were 44.92?±?10.93 μg/l and 66.13?±?18.97 μg/dl in febrile convulsion, they were found to be 62.98?±?9.80 μg/l and 107.87?±?28.79 μg/dl in healthy children. Meanwhile, copper levels were 146.40?±?23.51 μg/dl in the patients and 137.63?±?24.19 μg/dl in the control group, respectively. This study shows that selenium and zinc play an important role in the pathogenesis of febrile convulsion. 相似文献
25.
桑蓟马Pseudodendrothrips mori是桑树的一种主要害虫。它的寄生直接影响供桑叶的质量和产量。我们通过泰勒幂法则和Morisita的散度指标对桑树蓟马在植株和桑园内的空间分布进行检验,结果显示:P.mori种群在植株内和桑园里的分布都存在局部化。桑树中蓟马的分布在树内显示出幼虫蓟马位于低层(从上面叶子起5-10层),但成虫更喜欢上层(从上面叶子起1-5层)。同一植株叶子的不同方向上蓟马密度没有出现明显变化。桑园内蓟马主要分布在桑园东部、南部和北部的植株上,中部,西部植株上的蓟马密度较低。P.mori的成虫和幼虫在叶子上的分布呈现明显聚集化。 相似文献
26.
Amani M Moosavi-Movahedi AA Floris G Mura A Kurganov BI Ahmad F Saboury AA 《Biophysical chemistry》2007,125(2-3):254-259
Thermal denaturation of Euphorbia latex amine oxidase (ELAO) has been studied by enzymatic activity, circular dichroism and differential scanning calorimetry. Thermal denaturation of ELAO is shown to be an irreversible process. Checking the validity of two-state it really describes satisfactorily the thermal denaturation of ELAO. Based on this model we obtain the activation energy, parameter T(*) (the absolute temperature at which the rate constant of denaturation is equal to 1 min(-1)), and total enthalpy of ELAO denaturation. HPLC experiments show that the thermal denatured enzyme conserves its dimeric state. The N(2)-->kD(2) model for thermal denaturation of ELAO is proposed: where N(2) and D(2) are the native and denatured dimer, respectively. 相似文献
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29.
Shamsipur M Fattahi N 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2011,879(28):2978-2983
A simple, rapid and sensitive method based on dispersive liquid-liquid microextraction (DLLME) combined with high-performance liquid chromatography-ultraviolet detection (HPLC-UV) was used to determine opium alkaloids in urine samples. Some effective parameters on extraction were studied and optimized. Under the optimum conditions, enrichment factors and recoveries for different opiates are in the range of 63.0-104.5 and 31.5-52.2%, respectively. The calibration graphs are linear in the range of 0.50-500 μg L(-1) and limit of detections (LODs) are in the range of 0.2-10 μg L(-1). The relative standard deviations (RSDs) for 200 μg L(-1) of morphine, codeine and thebaine, 5.0 μg L(-1) of papaverine and 10.0 μg L(-1) of noscapine in diluted urine sample are in the range of 2.8-6.1% (n=7). The relative recoveries of urine samples spiked with alkaloids are 84.3-106.0%. The obtained results show that DLLME combined with HPLC-UV is a fast and simple method for the determination of opium alkaloids in urine samples. 相似文献
30.
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