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131.
Hamid Forootanfar Mojtaba Shakibaie Zahra Bagherzadeh Marzieh Aghaie-Khozani Nastaran Nafissi-Varcheh Hamid Reza Monsef-Esfahani Mohammad Ali Faramarzi 《Journal of applied phycology》2013,25(1):51-57
The present study aimed at evaluating the ability of some isolated cyanobacterial and microalgal strains for the removal of ρ-chlorophenol (ρ-CP), an environmentally harmful contaminant. To identify the most efficient species, a screening program was carried out using 15 microalgal and cyanobacterial strains. Among them, Tetraselmis suecica was able to remove 67 % of the ρ-chlorophenol at an initial concentration of 20 mg L?1 from the medium within a 10-day period. The efficacy of the process was dependent on the ρ-chlorophenol concentration. At concentrations above 60 mg L?1 of the pollutant, no removal was observed due to the inhibitory effect of ρ-chlorophenol on the T. suecica cells. The effect of cell immobilization in alginate beads on T. suecica removal capacity was also examined. Using this technique, the removal efficacy for the initial ρ-CP concentration of 20 mg L?1 increased up to 94 %. 相似文献
132.
Reza Ebrahimzadeh-Vesal Seyed kianush Hosseini Fereshteh Rezakhanlu Pupak Derakhshandeh-Peykar 《Reports of Biochemistry & Molecular Biology》2013,2(1):52-55
Holt-Oram syndrome (HOS) is a developmental disorder inherited in an autosomal-dominant pattern. Affected organs are the heart and forelimbs with upper extremity skeletal defects and congenital heart malformation. In this study we present three cases of HOS in the same family. In one of these three individuals we detected a transition of C to T (CTG-GTT, V205V) in exon 7 of the TBX5 gene. This nucleotide change causes no amino acid change and potential pathologic effects remain unknown.Key Words: Holt-Oram syndrome, Congenital heart malformation, TBX5 gene 相似文献
133.
Umesh C. S. Yadav Amarjit S. Naura Leopoldo Aguilera-Aguirre Istvan Boldogh Hamid A. Boulares William J. Calhoun Kota V. Ramana Satish K. Srivastava 《PloS one》2013,8(2)
Background
Long-term and unresolved airway inflammation and airway remodeling, characteristic features of chronic asthma, if not treated could lead to permanent structural changes in the airways. Aldose reductase (AR), an aldo-sugar and lipid aldehyde metabolizing enzyme, mediates allergen-induced airway inflammation in mice, but its role in the airway remodeling is not known. In the present study, we have examined the role of AR on airway remodeling using ovalbumin (OVA)-induced chronic asthma mouse model and cultured human primary airway epithelial cells (SAECs) and mouse lung fibroblasts (mLFs).Methods
Airway remodeling in chronic asthma model was established in mice sensitized and challenged twice a week with OVA for 6 weeks. AR inhibitor, fidarestat, was administered orally in drinking water after first challenge. Inflammatory cells infiltration in the lungs and goblet cell metaplasia, airway thickening, collagen deposition and airway hyper-responsiveness (AHR) in response to increasing doses of methacholine were assessed. The TGFβ1-induced epithelial-mesenchymal transition (EMT) in SAECs and changes in mLFs were examined to investigate AR-mediated molecular mechanism(s) of airway remodeling.Results
In the OVA-exposed mice for 6 wks inflammatory cells infiltration, levels of inflammatory cytokines and chemokines, goblet cell metaplasia, collagen deposition and AHR were significantly decreased by treatment with AR inhibitor, fidarestat. Further, inhibition of AR prevented TGFβ1-induced altered expression of E-cadherin, Vimentin, Occludin, and MMP-2 in SAECs, and alpha-smooth muscle actin and fibronectin in mLFs. Further, in SAECs, AR inhibition prevented TGFβ1- induced activation of PI3K/AKT/GSK3β pathway but not the phosphorylation of Smad2/3.Conclusion
Our results demonstrate that allergen-induced airway remodeling is mediated by AR and its inhibition blocks the progression of remodeling via inhibiting TGFβ1-induced Smad-independent and PI3K/AKT/GSK3β-dependent pathway. 相似文献134.
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137.
Asghar Mohammadi Hesari Hamid Reza Shamlouei Ali Raoof Toosi 《Journal of molecular modeling》2016,22(8):189
The effect of alkali metal oxides M n O (M?=?Li, Na, K; n?=?2, 3, 4) on the geometric, electronic, and linear and nonlinear optical properties of the Mg12O12 nanocage was investigated by density-functional-based methods. According to the computational results, these alkali metal oxides are adsorbed on the Mg12O12 nanocage because this adsorption reduces its energy gap. The static first hyperpolarizability (β 0) of the nanocage is dramatically increased in the presence of the alkali metal oxides, with the greatest increase seen in the presence of the superalkalis (i.e., M3O; M?=?Li, Na, and K). The highest first hyperpolarizability (β 0?≈?600,000 a.u.) was calculated for K3O@Mg12O12, which was considerably more than that for Mg12O12. The thermodynamic properties and relative stabilities of these inorganic compounds are discussed. 相似文献
138.
Measurement of some Benzylisoquinoline Alkaloids in Different Organs of Persian Poppy during Ontogenetical Stages 下载免费PDF全文
Mahdi Rezaei Mohammad Reza Naghavi Abdol Hadi Hosseinzadeh Alireza Abbasi 《化学与生物多样性》2016,13(5):539-543
Papaver bracteatum, a perennial species, has been known as a rich source of thebaine and a potential alternative to Papaver somniferum for the production of codeine and some semisynthetic antagonist drugs. In this study, ion mobility spectrum (IMS) of the root, leaf, bottom part of stem, upper part of stem, capsule wall, petal, and capsule content during developmental stages of P. bracteatum including annual rosette, perennial rosette, bud initiation, pendulous bud, preflowering, and lancing were investigated. The IMS revealed thebaine, papaverine, and noscapine as the major components of the extracted alkaloids. Based on the results of the study it appears that, at least in part, there is a competition among the biosynthesis pathways of papaverine, noscapine, and morphinan alkaloids from a common source . Root and capsule wall were the most potent organs for extraction of thebaine, while lancing stage was the best developmental stage for thebaine exploitation. However, it seems that total biomass of root and capsule wall plays a key role in the final selection of favorite organ. Although papaverine and noscapine in the stem at preflowering stage had the most quantity, significant amounts were found in the capsule wall. In general, total alkaloid content of leaf was lower than the other plant parts. 相似文献
139.
Variation in Essential Oil Yield and Composition of Dorema aucheri Boiss., an Endemic Medicinal Plant Collected from Wild Populations in Natural Habitats 下载免费PDF全文
In the present research, variability in essential oil (EO) composition of five Dorema aucheri populations collected from natural habitats in different regions of Iran, were investigated. The EO content of populations varied from 0.28 to 0.68%. According to gas chromatography/mass spectrometry analysis, β‐caryophyllene (7.17 – 35.73%), thymol (23.45 – 29.64%), β‐gurjunene (2.58 – 5.89%), carvacrol (1.32 – 2.67%) and cuparene (1.97 – 2.98%) were the major components. Hierarchical cluster, principal component and canonical correspondence analyses classified the studied populations into three groups based on major EO components. The environmental parameters of the collected sites were also evaluated. According to the results, it might be suggested that sandy soils with high mean annual precipitation were major environmental factors influencing the amount of β‐caryophyllene, while thymol, cuparene and caryophyllen oxide increased in silty and clay soils. Finally, the population collected in high altitudes and clay soils had higher amount of β‐gurjunene. 相似文献
140.
Parisa Tajer-Mohammad-Ghazvini Rouha Kasra-Kermanshahi Ahmad Nozad-Golikand Majid Sadeghizadeh Saeid Ghorbanzadeh-Mashkani Reza Dabbagh 《Bioprocess and biosystems engineering》2016,39(12):1899-1911
Bioremediation of toxic metals by magnetotactic bacteria and magnetic separation of metal-loaded magnetotactic bacteria are of great interest. This bioprocess technique is rapid, efficient, economical, and environmentally friendly. In this study, cobalt removal potential of a novel isolated magnetotactic bacterium (Alphaproteobacterium MTB-KTN90) as a new biosorbent was investigated. The effects of various environmental parameters in the cobalt removal and the technique of magnetic separation of cobalt-loaded bacterial cells were studied. Cobalt removal by MTB-KTN90 was very sensitive to pH solution; higher biosorption capacity was observed around pH 6.5–7.0. When biomass concentration increased from 0.009 to 0.09 g/l, the biosorption efficiency increased from 13.87 % to 19.22 %. The sorption of cobalt by MTB-KTN90 was rapid during the first 15 min (859.17 mg/g dry weight). With the increasing of cobalt concentrations from 1 to 225 mg/l, the specific cobalt uptake increased. Maximum cobalt removal (1160.51 ± 15.42 mg/g dry weight) took place at optimum conditions; pH 7.0 with initial cobalt concentration of 115 mg/l at 60 min by 0.015 g/l of dry biomass. The results showed maximum values for constants of Langmuir and Freundlich models so far. The biosorption mechanisms were studied with FTIR, PIXE, and FESEM analysis. Cobalt-loaded MTB-KTN90 had ability to separate from solution by a simple magnetic separator. Magnetic response in MTB-KTN90 is due to the presence of unique intracellular magnetic nanoparticles (magnetosomes). The orientation magnetic separation results indicated that 88.55 % of cobalt was removed from solution. Consequently, Alphaproteobacterium MTB-KTN90 as a new biosorbent opens up good opportunities for the magnetic removal of cobalt from the polluted aquatic environments. 相似文献