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11.
Asim Mehmood Umal Baneen Ahmad Zaheer Muhammad Wasim Sajid Abrar Hussain Shahzad Saleem Qudsia Yousafi Hamid Rashid Hassan Riaz Awais Ihsan Farrukh Jamil Yasar Sajjad Nageena Zahid Muhammad Shahzad Anjam Muhammad Arshad Zeenat Mirza Sajjad Karim Mahmood Rasool 《Saudi Journal of Biological Sciences》2019,26(7):1485-1491
ObjectivePhosphorous is an essential micronutrient of plants and involved in critical biological functions. In nature, phosphorous is mostly present in immobilized inorganic mineral and in the fixed organic form including phytic acid and phosphoesteric compounds. However, the bioavailability of bound phosphorous could be enhanced by the use of phosphate solubilizing microorganisms such as bacteria and fungi. The phytases are widespread in an environment and have been isolated from different sources comprising bacteria and fungi.MethodologyIn current studies, we show the successful use of gamma rays and EMS (Ethyl Methane Sulphonate) mutagenesis for enhanced activity of phytases in a fungal strain Sporotrichum thermophile.ResultsWe report an improved strain ST2 that could produce a clear halo zone around the colony, up to 24 mm. The maximum enzymatic activity was found of 382 U/mL on pH 5.5. However, the phytase activity was improved to 387 U/ml at 45 °C. We also report that the mutants produced through EMS showed the greater potential for phytase production.ConclusionThe current study highlights the potential of EMS mutagenesis for strain improvement over physical mutagens. 相似文献
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Mahmood Hossain Siddique Mohammad Raqibul Hasan Rubaiot Abdullah S. M. Costello Liam Matieu Henry Iqbal Md. Zaheer Akhter Mariam 《Wetlands Ecology and Management》2019,27(4):553-569
Wetlands Ecology and Management - Bangladesh has the single largest tract of naturally growing mangrove forest as well as the world’s largest manmade mangrove forest on newly accreted land in... 相似文献
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Lipoxygenase inhibiting and antioxidant oligostilbene and monoterpene galactoside from Paeonia emodi
Riaz N Malik A Rehman AU Ahmed Z Muhammad P Nawaz SA Siddiqui J Choudhary MI 《Phytochemistry》2004,65(8):1129-1135
Paeoninol and paeonin C, oligostilbene and monoterpene galactoside, have been isolated from the methanolic extract of the fruits of Paeonia emodi. Their structures have been assigned on the basis of spectral analysis including 1D and 2D NMR techniques. In addition, 4-hydroxybenzoic acid 3, gallic acid 4 and methyl gallate 5 have also been reported for the first time from this species. Compounds 1 and 2 have displayed potent inhibitory potential against enzyme lipoxygenase in a concentration-dependent fashion with the IC(50) values 0.77 and 99.5 microM, along with ABTS(.+) radical quenching activity with IC(50) values of 147.5 and 498.2 microM, respectively. 相似文献
16.
Baber SR Hyman AL Kadowitz PJ 《American journal of physiology. Heart and circulatory physiology》2003,285(6):H2399-H2410
The role of cyclooxygenase (COX)-1 and -2 in prostanoid formation and modulation of pressor responses to ANG II was investigated in the pulmonary and systemic vascular beds in the rat. In the present study, selective COX-1 and -2 inhibitors attenuated increases in pulmonary arterial pressure and decreases in systemic arterial pressure in response to arachidonic acid but did not alter responses to PGE1 or U-46619. The selective COX-1 and -2 inhibitors did not modify systemic pressor responses to injections or infusions of ANG II or pulmonary pressor responses to injections of the peptide. COX-2 inhibitors did not alter, whereas a COX-1 inhibitor depressed, arachidonic acid-induced platelet aggregation. These data provide evidence in support of the hypothesis that prostanoid synthesis occurs by way of the COX-1 and -2 pathways in the pulmonary and systemic vascular beds but that pressor responses to ANG II are not mediated or modulated by these pathways in the rat. 相似文献
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The present study deals with the flow and heat transfer analysis of two immiscible fluids in an inclined channel embedded in a porous medium. The channel is divided in two phases such that a third grade fluid occupies the phase I and a viscous fluid occupies the phase II. Both viscous and third grade fluids are electrically conducting. A constant magnetic field is imposed perpendicular to the channel walls. The mathematical model is developed by using Darcy''s and modified Darcy''s laws for viscous and third grade fluids respectively. The transformed ordinary differential equations are solved numerically using a shooting method. The obtained results are presented graphically and influence of emerging parameters is discussed in detail. 相似文献
18.
Baber SR Deng W Master RG Bunnell BA Taylor BK Murthy SN Hyman AL Kadowitz PJ 《American journal of physiology. Heart and circulatory physiology》2007,292(2):H1120-H1128
The administration of mesenchymal stem cells (MSCs) has been proposed for the treatment of pulmonary hypertension. However, the effect of intratracheally administered MSCs on the pulmonary vascular bed in monocrotaline-treated rats has not been determined. In the present study, the effect of intratracheal administration of rat MSCs (rMSCs) on monocrotaline-induced pulmonary hypertension and impaired endothelium-dependent responses were investigated in the rat. Intravenous injection of monocrotaline increased pulmonary arterial pressure and vascular resistance and decreased pulmonary vascular responses to acetylcholine without altering responses to sodium nitroprusside and without altering systemic responses to the vasodilator agents when responses were evaluated at 5 wk. The intratracheal injection of 3 x 10(6) rMSCs 2 wk after administration of monocrotaline attenuated the rise in pulmonary arterial pressure and pulmonary vascular resistance and restored pulmonary responses to acetylcholine toward values measured in control rats. Treatment with rMSCs decreased the right ventricular hypertrophy induced by monocrotaline. Immunohistochemical studies showed widespread distribution of lacZ-labeled rMSCs in lung parenchyma surrounding airways in monocrotaline-treated rats. Immunofluorescence studies revealed that transplanted rMSCs retained expression of von Willebrand factor and smooth muscle actin markers specific for endothelial and smooth muscle phenotypes. However, immunolabeled cells were not detected in the wall of pulmonary vessels. These data suggest that the decrease in pulmonary vascular resistance and improvement in response to acetylcholine an endothelium-dependent vasodilator in monocrotaline-treated rats may result from a paracrine effect of the transplanted rMSCs in lung parenchyma, which improves vascular endothelial function in the monocrotaline-injured lung. 相似文献
19.
Trujillo JI Huang HC Neumann WL Mahoney MW Long S Huang W Garland DJ Kusturin C Abbas Z South MS Reitz DB 《Bioorganic & medicinal chemistry letters》2007,17(16):4568-4574
Herein is described the design, synthesis, and enzymatic activity of a series of substituted pyrazinones as inhibitors of the TF/VIIa complex. These inhibitors were designed to explore replacement and variation of the P1 amidine described previously [J. Med. Chem.2003, 46, 4050]. The P1 needle replacements were selected based upon their reduced basicity compared to the parent phenyl amidine (pKa approximately 12). A contributing factor towards the oral bioavailability of a compound is the ionization state of the compound in the intestinal tract. The desired outcome of the study was to identify an orally bioavailable TF-VIIa inhibitor. 相似文献
20.
Glia maturation factor (GMF), a highly conserved brain-specific protein, isolated, sequenced and cloned in our laboratory.
Overexpression of GMF in astrocytes induces the production and secretion of granulocyte-macrophage-colony stimulating factor
(GM-CSF), and subsequent immune activation of microglia, expression of several proinflammatory genes including major histocompatibility
complex proteins, IL-1β, and MIP-1β, all associated with the development of experimental autoimmune encephalomyelitis (EAE),
the animal model for multiple sclerosis. Based on GMF’s ability to activate microglia and induce well-established proinflammatory
mediators, including GM-CSF, we hypothesize that GMF is involved in the pathogenesis of inflammatory disease EAE. In this
present investigation, using GMF-deficient mice, we study the role of GMF and how the lack of GMF affects the EAE disease.
Our results show a significant decrease in incidence, delay in onset, and reduced severity of EAE in GMF-deficient mice, and
support the hypothesis that GMF plays a major role in the pathogenesis of disease. 相似文献