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Bifunctional CYP81AA proteins catalyse identical hydroxylations but alternative regioselective phenol couplings in plant xanthone biosynthesis

Research Abstract
Xanthones are natural products present in plants and microorganisms. In plants, their biosynthesis starts with regioselective cyclization of 2,3′,4,6-tetrahydroxybenzophenone to either 1,3,5- or 1,3,7-trihydroxyxanthones, catalysed by cytochrome P450 (CYP) enzymes. Here we isolate and express CYP81AA-coding sequences from Hypericum calycinum and H. perforatum in yeast. Microsomes catalyse two consecutive reactions, that is, 3′-hydroxylation of 2,4,6-trihydroxybenzophenone and C–O phenol coupling of the resulting 2,3′,4,6-tetrahydroxybenzophenone. Relative to the inserted 3′-hydroxyl, the orthologues Hc/HpCYP81AA1 cyclize via the para position to form 1,3,7-trihydroxyxanthone, whereas the paralogue HpCYP81AA2 directs cyclization to the ortho position, yielding the isomeric 1,3,5-trihydroxyxanthone. Homology modelling and reciprocal mutagenesis reveal the impact of S375, L378 and A483 on controlling the regioselectivity of HpCYP81AA2, which is converted into HpCYP81AA1 by sextuple mutation. However, the reciprocal mutations in HpCYP81AA1 barely affect its regiospecificity. Product docking rationalizes the alternative C–O phenol coupling reactions. Our results help understand the machinery of bifunctional CYPs.
Research Authors
Islam El-Awaad, Marco Bocola, Till Beuerle, Benye Liu and Ludger Beerhues
Research Department
Research Journal
Nature Communications
Research Publisher
NULL
Research Rank
1
Research Vol
7
Research Website
doi:10.1038/ncomms11472
Research Year
2016

Phytochemical and biological studies on Lepidium virginicum L. leaves

Research Abstract
NULL
Research Authors
Ahmed M. El-Moghazy, Samia M. El-Sayyad, Zedan Z. Ibraheim and
Islam A. El-Awaad
Research Department
Research Journal
Assiut University 6th International Pharmaceutical Sciences Conference, Faculty of Pharmacy, Assiut, Egypt
Research Member
Ahmed Mohamed El-Moghazy Shoeib
Research Publisher
NULL
Research Rank
4
Research Vol
NULL
Research Website
NULL
Research Year
2008

Phytochemical and biological studies on Lepidium virginicum L. leaves

Research Abstract
NULL
Research Authors
Ahmed M. El-Moghazy, Samia M. El-Sayyad, Zedan Z. Ibraheim and
Islam A. El-Awaad
Research Department
Research Journal
Assiut University 6th International Pharmaceutical Sciences Conference, Faculty of Pharmacy, Assiut, Egypt
Research Publisher
NULL
Research Rank
4
Research Vol
NULL
Research Website
NULL
Research Year
2008

Phytochemical and biological studies on Lepidium virginicum L. leaves

Research Abstract
NULL
Research Authors
Ahmed M. El-Moghazy, Samia M. El-Sayyad, Zedan Z. Ibraheim and
Islam A. El-Awaad
Research Department
Research Journal
Assiut University 6th International Pharmaceutical Sciences Conference, Faculty of Pharmacy, Assiut, Egypt
Research Member
Zedan Zeid Ibraheim Hammad
Research Publisher
NULL
Research Rank
4
Research Vol
NULL
Research Website
NULL
Research Year
2008

Phytochemical and biological studies on Lepidium virginicum L. leaves

Research Abstract
NULL
Research Authors
Ahmed M. El-Moghazy, Samia M. El-Sayyad, Zedan Z. Ibraheim and
Islam A. El-Awaad
Research Department
Research Journal
Assiut University 6th International Pharmaceutical Sciences Conference, Faculty of Pharmacy, Assiut, Egypt
Research Publisher
NULL
Research Rank
4
Research Vol
NULL
Research Website
NULL
Research Year
2008

Factors Influencing Warfarin Response in Hospitalized Patients

Research Abstract
The objective of this study was to investigate the influence of simultaneous factors that potentially keep patients far from achieving target INR range at discharge in hospitalized patients. Prospective cross-sectional observational study conducted at the Cardiology Department and Intensive Care Unit (ICU) of the Assiut University Hospitals. One-hundred and twenty patients were enrolled in the study from July 2013 to January 2014. Outcome measures were discharge INRs, bleeding and thromboembolic episodes. Bivariate analysis and multinomial logistic regression were conducted to determine independent risk factors that can keep patients outside target INR range. Patients who were newly initiated warfarin on hospital admission were given low initiation dose (2.8 mg ± 0.9). They were more likely to have INR values below 1.5 during hospital stay, 13 (27.7%) patients compared with 9 (12.3%) previously treated patients, respectively (p= .034). We found that the best predictors of achieving below target INR range relative to within target INR range were; shorter hospital stay periods (OR, 0.82 for every day increase [95% CI, 0.72–0.94]), being a male patient (OR, 2.86 [95% CI, 1.05–7.69]), concurrent infection (OR, 0.21 [95% CI, 0.07–0.59]) and new initiation of warfarin therapy on hospital admission (OR, 3.73 [95% CI,1.28–10.9]). Gender, new initiation of warfarin therapy on hospital admission, shorter hospital stay periods and concurrent infection can have a significant effect on discharge INRs. Initiation of warfarin without giving loading doses increases the risk of having INRs below 1.5 during hospital stay and increases the likelihood of a patient to be discharged with INR below target range. Following warfarin dosing nomograms and careful monitoring of the effect of various factors on warfarin response should be greatly considered
Research Authors
Mahmoud I. Abdel-Aziz, Mostafa A. Sayed Ali, Ayman K.M. Hassan and Tahani H. Elfaham
Research Journal
Saudi Pharmaceutical Journal
Research Publisher
Elsevier
Research Rank
1
Research Vol
Vol. 23
Research Website
http://dx.doi.org/10.1016/j.jsps.2015.02.004
Research Year
2015

Factors Influencing Warfarin Response in Hospitalized Patients

Research Abstract
The objective of this study was to investigate the influence of simultaneous factors that potentially keep patients far from achieving target INR range at discharge in hospitalized patients. Prospective cross-sectional observational study conducted at the Cardiology Department and Intensive Care Unit (ICU) of the Assiut University Hospitals. One-hundred and twenty patients were enrolled in the study from July 2013 to January 2014. Outcome measures were discharge INRs, bleeding and thromboembolic episodes. Bivariate analysis and multinomial logistic regression were conducted to determine independent risk factors that can keep patients outside target INR range. Patients who were newly initiated warfarin on hospital admission were given low initiation dose (2.8 mg ± 0.9). They were more likely to have INR values below 1.5 during hospital stay, 13 (27.7%) patients compared with 9 (12.3%) previously treated patients, respectively (p= .034). We found that the best predictors of achieving below target INR range relative to within target INR range were; shorter hospital stay periods (OR, 0.82 for every day increase [95% CI, 0.72–0.94]), being a male patient (OR, 2.86 [95% CI, 1.05–7.69]), concurrent infection (OR, 0.21 [95% CI, 0.07–0.59]) and new initiation of warfarin therapy on hospital admission (OR, 3.73 [95% CI,1.28–10.9]). Gender, new initiation of warfarin therapy on hospital admission, shorter hospital stay periods and concurrent infection can have a significant effect on discharge INRs. Initiation of warfarin without giving loading doses increases the risk of having INRs below 1.5 during hospital stay and increases the likelihood of a patient to be discharged with INR below target range. Following warfarin dosing nomograms and careful monitoring of the effect of various factors on warfarin response should be greatly considered
Research Authors
Mahmoud I. Abdel-Aziz, Mostafa A. Sayed Ali, Ayman K.M. Hassan and Tahani H. Elfaham
Research Department
Research Journal
Saudi Pharmaceutical Journal
Research Member
Research Publisher
Elsevier
Research Rank
1
Research Vol
Vol. 23
Research Website
http://dx.doi.org/10.1016/j.jsps.2015.02.004
Research Year
2015

Factors Influencing Warfarin Response in Hospitalized Patients

Research Abstract
The objective of this study was to investigate the influence of simultaneous factors that potentially keep patients far from achieving target INR range at discharge in hospitalized patients. Prospective cross-sectional observational study conducted at the Cardiology Department and Intensive Care Unit (ICU) of the Assiut University Hospitals. One-hundred and twenty patients were enrolled in the study from July 2013 to January 2014. Outcome measures were discharge INRs, bleeding and thromboembolic episodes. Bivariate analysis and multinomial logistic regression were conducted to determine independent risk factors that can keep patients outside target INR range. Patients who were newly initiated warfarin on hospital admission were given low initiation dose (2.8 mg ± 0.9). They were more likely to have INR values below 1.5 during hospital stay, 13 (27.7%) patients compared with 9 (12.3%) previously treated patients, respectively (p= .034). We found that the best predictors of achieving below target INR range relative to within target INR range were; shorter hospital stay periods (OR, 0.82 for every day increase [95% CI, 0.72–0.94]), being a male patient (OR, 2.86 [95% CI, 1.05–7.69]), concurrent infection (OR, 0.21 [95% CI, 0.07–0.59]) and new initiation of warfarin therapy on hospital admission (OR, 3.73 [95% CI,1.28–10.9]). Gender, new initiation of warfarin therapy on hospital admission, shorter hospital stay periods and concurrent infection can have a significant effect on discharge INRs. Initiation of warfarin without giving loading doses increases the risk of having INRs below 1.5 during hospital stay and increases the likelihood of a patient to be discharged with INR below target range. Following warfarin dosing nomograms and careful monitoring of the effect of various factors on warfarin response should be greatly considered
Research Authors
Mahmoud I. Abdel-Aziz, Mostafa A. Sayed Ali, Ayman K.M. Hassan and Tahani H. Elfaham
Research Department
Research Journal
Saudi Pharmaceutical Journal
Research Publisher
Elsevier
Research Rank
1
Research Vol
Vol. 23
Research Website
http://dx.doi.org/10.1016/j.jsps.2015.02.004
Research Year
2015

Factors Influencing Warfarin Response in Hospitalized Patients

Research Abstract
The objective of this study was to investigate the influence of simultaneous factors that potentially keep patients far from achieving target INR range at discharge in hospitalized patients. Prospective cross-sectional observational study conducted at the Cardiology Department and Intensive Care Unit (ICU) of the Assiut University Hospitals. One-hundred and twenty patients were enrolled in the study from July 2013 to January 2014. Outcome measures were discharge INRs, bleeding and thromboembolic episodes. Bivariate analysis and multinomial logistic regression were conducted to determine independent risk factors that can keep patients outside target INR range. Patients who were newly initiated warfarin on hospital admission were given low initiation dose (2.8 mg ± 0.9). They were more likely to have INR values below 1.5 during hospital stay, 13 (27.7%) patients compared with 9 (12.3%) previously treated patients, respectively (p= .034). We found that the best predictors of achieving below target INR range relative to within target INR range were; shorter hospital stay periods (OR, 0.82 for every day increase [95% CI, 0.72–0.94]), being a male patient (OR, 2.86 [95% CI, 1.05–7.69]), concurrent infection (OR, 0.21 [95% CI, 0.07–0.59]) and new initiation of warfarin therapy on hospital admission (OR, 3.73 [95% CI,1.28–10.9]). Gender, new initiation of warfarin therapy on hospital admission, shorter hospital stay periods and concurrent infection can have a significant effect on discharge INRs. Initiation of warfarin without giving loading doses increases the risk of having INRs below 1.5 during hospital stay and increases the likelihood of a patient to be discharged with INR below target range. Following warfarin dosing nomograms and careful monitoring of the effect of various factors on warfarin response should be greatly considered
Research Authors
Mahmoud I. Abdel-Aziz, Mostafa A. Sayed Ali, Ayman K.M. Hassan and Tahani H. Elfaham
Research Department
Research Journal
Saudi Pharmaceutical Journal
Research Publisher
Elsevier
Research Rank
1
Research Vol
Vol. 23
Research Website
http://dx.doi.org/10.1016/j.jsps.2015.02.004
Research Year
2015

Ingenines A and B, two new alkaloids from the Indonesian sponge Acanthostrongylophora ingens

Research Abstract
As a continuation of the work on EtOAc fraction of the Indonesian sponge Acanthostrongylophora ingens, 2 new alkaloids: one pyrimidine-β-carboline alkaloid named ingenine A (2) and one pyrimidine-γ-carboline alkaloid named ingenine B (3), along with annomontine (1) were isolated. Their structures were unambiguously established on the basis of NMR spectroscopy (1 H, 13C, 1 H-1 H COSY, HMQC, and HMBC) and mass spectral data. This is the first report of isolation pyrimidine-γ-carboline alkaloid from natural source. Compounds 1 and 3 showed pronounced cytotoxicity against the murine lymphoma L5178Y cancer cell line with ED50 7.8 and 9.1 μg/mL respectively, while compound 2 showed weak activity.
Research Authors
Sabrin RM Ibrahim, Gamal A Mohamed, Mohamed F Zayed and Hanaa M Sayed
Research Department
Research Journal
Drug Research, DOI: 10.1055/s-0034-1384577
Research Member
Research Publisher
Thieme
Research Rank
1
Research Vol
Vol. 65, No. 7
Research Website
https://www.thieme-connect.com/products/ejournals/abstract/10.1055/s-0034-1384577
Research Year
2015
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