1,2-Benzothiazine derivatives methyl 3-methoxy-4-oxo-3,4-dihydro-2H-benzo[e] [1,2]thiazine-3-carboxylate 1,1-dioxide（1） and methyl 2-ethyl-3-hydroxy-4-oxo-3,4-dihydro-2Hbenzo[e][1,2]thiazine-3-carboxylate 1,1-dioxid...1,2-Benzothiazine derivatives methyl 3-methoxy-4-oxo-3,4-dihydro-2H-benzo[e] [1,2]thiazine-3-carboxylate 1,1-dioxide（1） and methyl 2-ethyl-3-hydroxy-4-oxo-3,4-dihydro-2Hbenzo[e][1,2]thiazine-3-carboxylate 1,1-dioxide（2） were synthesized, and characterized by spectroscopic techniques; 1H-NMR and infrared（IR） spectroscopy. Crystals of 1 and 2 were grown by slow evaporation of methanol and ethyl acetate, respectively and their crystal structures were investigated by single-crystal X-ray diffraction analysis. Geometric properties were calculated by the B3 LYP method of density functional theory（DFT） at the 6-31G＋（d） basis set to compare with the experimental data. Simulated properties were found in strong agreement with the experimental ones. Intermolecular forces have also been modeled in order to investigate the strength of packing and strong hydrogen bonding was observed in both compounds 1 and 2. Electronic properties such as Ionization Potential（IP）, Electron Affinities（EA） and coefficients of the highest occupied molecular orbital（HOMO） and the lowest unoccupied molecular orbital（LUMO） of com- pounds 1 and 2 were simulated for the first time.展开更多
Single-phase Zn_(0.95)Co_(0.05)O and Zn_(0.90)Co_(0.05)Al_(0.05)O samples were prepared by a novel combustion method.Xray diffraction studies exhibit the pure phase wurtzite structure of doped ZnO.Energy dispersive x-...Single-phase Zn_(0.95)Co_(0.05)O and Zn_(0.90)Co_(0.05)Al_(0.05)O samples were prepared by a novel combustion method.Xray diffraction studies exhibit the pure phase wurtzite structure of doped ZnO.Energy dispersive x-ray analysis confirms the incorporation of dopants into the host material.Scanning electron microscopy shows the ordered morphology in both of the samples.Temperature-dependent resistivity analysis describes the expected semiconducting behavior that is similar to the parent ZnO materials.Room-temperature magnetic measurements reveal the absence of ferromagnetism in Co-doped ZnO,while the Co and Al co-doped sample displays apparent room-temperature ferromagnetic behavior.The decrease of resistivity and presence of ferromagnetic behavior in Al-doped ZnCoO system corroborate the significant role of free carriers.展开更多
Hydroxyapatite (HA) is a synthetic ceramic which is used in numerous biomedical applications. However, its use is restricted in load bearing applications. A novel batch hydrothermal method is indigenously developed to...Hydroxyapatite (HA) is a synthetic ceramic which is used in numerous biomedical applications. However, its use is restricted in load bearing applications. A novel batch hydrothermal method is indigenously developed to synthesize fine size, crystalline hydroxyapatite (HA) and titania doped hydroxyapatite (TiO2-HA) powders with distinct phase formation. Powders were characterized using XRD, FTIR and DSC-TGA. Sharp peaks in HA XRD pattern after sintering at 1000°C indicate significant crystallinity while sharp peaks in TiO2 XRD pattern at 27°, 36° and 5° after sintering indicate anatase to rutile transformation. This fact is also confirmed by FTIR and DSC-TGA Plots.展开更多
Objective: To explore RNA dependent RNA polymerase of Chikungunya virus(CHIKV) and develop T cell based epitopes with high antigenicity and good binding affinity for the human leukocyte antigen(HLA) classes as targets...Objective: To explore RNA dependent RNA polymerase of Chikungunya virus(CHIKV) and develop T cell based epitopes with high antigenicity and good binding affinity for the human leukocyte antigen(HLA) classes as targets for epitopes based CHIKV vaccine. Methods: In this study we downloaded 371 non-structural protein 4 protein sequences of CHIKV belonging to different regions of the world from the US National Institute of Allergy and Infectious Diseases(NIAID) virus pathogen resource database. All the sequences were aligned by using CLUSTALW software and a consensus sequence was developed by using Uni Pro U Gene Software version 1.2.1. PropredⅠand Propred software were used to predict HLAⅠ and HLAⅡ binding promiscuous epitopes from the consensus sequence of non-structural protein 4 protein. The predicted epitopes were analyzed to determine their antigenicity through Vaxijen server version 2.0. All the HLAⅠ binding epitopes were scanned to determine their immunogenic potential through the Immune Epitope Database(IEDB). All the predicted epitopes of our study were fed to IEDB database to determine whether they had been tested earlier. Results: Twenty two HLA class Ⅱ epitopes and eight HLA classⅠepitopes were predicted. The promiscuous epitopes WMNMEVKII at position 486–494 and VRRLNAVLL at 331–339 were found to bind with 37 and 36 of the 51 HLA class Ⅱ alleles respectively. Epitope MANRSRYQS at position 58–66 and epitopes YQSRKVENM at positions 64–72 were predicted to bind with 12 and 9 HLAⅠI alleles with antigenicity scores of 0.754 9 and 1.013 0 respectively. Epitope YSPPINVRL was predicted to bind 18 HLAⅠ alleles and its antigenicity score was 1.425 9 and immunogenicity score was 0.173 83. This epitope is very useful in the preparation of a universal vaccine against CHIKV infection. Conclusions: Epitopes reported in this study showed promiscuity, antigenicity as well as good binding affinity for the HLA classes. These epitopes will provide the baseline for development of efficacious vaccine for CHIKV.展开更多
Keratin constitutes the major component of the feather,hair,hooves,horns,and wool represents a group of biological material having high cysteine content(7–13%)as compared to other structural proteins.Keratin-based bi...Keratin constitutes the major component of the feather,hair,hooves,horns,and wool represents a group of biological material having high cysteine content(7–13%)as compared to other structural proteins.Keratin-based biomaterials have been investigated extensively over the past few decades due to their intrinsic biological properties and excellent biocompatibility.Unlike other natural polymers such as starch,collagen,chitosan,the complex three-dimensional structure of keratin requires the use of harsh chemical conditions for their dissolution and extraction.The most commonly used methods for keratin extraction are oxidation,reduction,steam explosion,microbial method,microwave irradiation and use of ionic liquids.Keratin-based materials have been used extensively for various biomedical applications such as drug delivery,wound healing,tissue engineering.This review covers the structure,properties,history of keratin research,methods of extraction and some recent advancements related to the use of keratin derived biomaterials in the form of a 3-D scaffold,films,fibers,and hydrogels.展开更多
基金funded by the Saudi Basic Industries Corporation(SABIC) and the Deanship of Scientific Research(DSR),King Abdulaziz University,Jeddah,under grant no.(MS/15/396/1434)
文摘1,2-Benzothiazine derivatives methyl 3-methoxy-4-oxo-3,4-dihydro-2H-benzo[e] [1,2]thiazine-3-carboxylate 1,1-dioxide（1） and methyl 2-ethyl-3-hydroxy-4-oxo-3,4-dihydro-2Hbenzo[e][1,2]thiazine-3-carboxylate 1,1-dioxide（2） were synthesized, and characterized by spectroscopic techniques; 1H-NMR and infrared（IR） spectroscopy. Crystals of 1 and 2 were grown by slow evaporation of methanol and ethyl acetate, respectively and their crystal structures were investigated by single-crystal X-ray diffraction analysis. Geometric properties were calculated by the B3 LYP method of density functional theory（DFT） at the 6-31G＋（d） basis set to compare with the experimental data. Simulated properties were found in strong agreement with the experimental ones. Intermolecular forces have also been modeled in order to investigate the strength of packing and strong hydrogen bonding was observed in both compounds 1 and 2. Electronic properties such as Ionization Potential（IP）, Electron Affinities（EA） and coefficients of the highest occupied molecular orbital（HOMO） and the lowest unoccupied molecular orbital（LUMO） of com- pounds 1 and 2 were simulated for the first time.
基金by the Higher Education Commission(HEC)of Pakistan under the indigenous Ph.D.fellowship 5000 Scheme.
文摘Single-phase Zn_(0.95)Co_(0.05)O and Zn_(0.90)Co_(0.05)Al_(0.05)O samples were prepared by a novel combustion method.Xray diffraction studies exhibit the pure phase wurtzite structure of doped ZnO.Energy dispersive x-ray analysis confirms the incorporation of dopants into the host material.Scanning electron microscopy shows the ordered morphology in both of the samples.Temperature-dependent resistivity analysis describes the expected semiconducting behavior that is similar to the parent ZnO materials.Room-temperature magnetic measurements reveal the absence of ferromagnetism in Co-doped ZnO,while the Co and Al co-doped sample displays apparent room-temperature ferromagnetic behavior.The decrease of resistivity and presence of ferromagnetic behavior in Al-doped ZnCoO system corroborate the significant role of free carriers.
文摘Hydroxyapatite (HA) is a synthetic ceramic which is used in numerous biomedical applications. However, its use is restricted in load bearing applications. A novel batch hydrothermal method is indigenously developed to synthesize fine size, crystalline hydroxyapatite (HA) and titania doped hydroxyapatite (TiO2-HA) powders with distinct phase formation. Powders were characterized using XRD, FTIR and DSC-TGA. Sharp peaks in HA XRD pattern after sintering at 1000°C indicate significant crystallinity while sharp peaks in TiO2 XRD pattern at 27°, 36° and 5° after sintering indicate anatase to rutile transformation. This fact is also confirmed by FTIR and DSC-TGA Plots.
文摘Objective: To explore RNA dependent RNA polymerase of Chikungunya virus(CHIKV) and develop T cell based epitopes with high antigenicity and good binding affinity for the human leukocyte antigen(HLA) classes as targets for epitopes based CHIKV vaccine. Methods: In this study we downloaded 371 non-structural protein 4 protein sequences of CHIKV belonging to different regions of the world from the US National Institute of Allergy and Infectious Diseases(NIAID) virus pathogen resource database. All the sequences were aligned by using CLUSTALW software and a consensus sequence was developed by using Uni Pro U Gene Software version 1.2.1. PropredⅠand Propred software were used to predict HLAⅠ and HLAⅡ binding promiscuous epitopes from the consensus sequence of non-structural protein 4 protein. The predicted epitopes were analyzed to determine their antigenicity through Vaxijen server version 2.0. All the HLAⅠ binding epitopes were scanned to determine their immunogenic potential through the Immune Epitope Database(IEDB). All the predicted epitopes of our study were fed to IEDB database to determine whether they had been tested earlier. Results: Twenty two HLA class Ⅱ epitopes and eight HLA classⅠepitopes were predicted. The promiscuous epitopes WMNMEVKII at position 486–494 and VRRLNAVLL at 331–339 were found to bind with 37 and 36 of the 51 HLA class Ⅱ alleles respectively. Epitope MANRSRYQS at position 58–66 and epitopes YQSRKVENM at positions 64–72 were predicted to bind with 12 and 9 HLAⅠI alleles with antigenicity scores of 0.754 9 and 1.013 0 respectively. Epitope YSPPINVRL was predicted to bind 18 HLAⅠ alleles and its antigenicity score was 1.425 9 and immunogenicity score was 0.173 83. This epitope is very useful in the preparation of a universal vaccine against CHIKV infection. Conclusions: Epitopes reported in this study showed promiscuity, antigenicity as well as good binding affinity for the HLA classes. These epitopes will provide the baseline for development of efficacious vaccine for CHIKV.
基金supported by Department of Anatomy,University of Otago,Otago,9016,New Zealand.
文摘Keratin constitutes the major component of the feather,hair,hooves,horns,and wool represents a group of biological material having high cysteine content(7–13%)as compared to other structural proteins.Keratin-based biomaterials have been investigated extensively over the past few decades due to their intrinsic biological properties and excellent biocompatibility.Unlike other natural polymers such as starch,collagen,chitosan,the complex three-dimensional structure of keratin requires the use of harsh chemical conditions for their dissolution and extraction.The most commonly used methods for keratin extraction are oxidation,reduction,steam explosion,microbial method,microwave irradiation and use of ionic liquids.Keratin-based materials have been used extensively for various biomedical applications such as drug delivery,wound healing,tissue engineering.This review covers the structure,properties,history of keratin research,methods of extraction and some recent advancements related to the use of keratin derived biomaterials in the form of a 3-D scaffold,films,fibers,and hydrogels.
