Bioactive ceramic scaffolds HA·TCP, aimed to be applied in clinic, were evaluated both in vitro and in vivo models. HA·TCP was supposed as a completely biodegradable material and designed as a scaffold to be...Bioactive ceramic scaffolds HA·TCP, aimed to be applied in clinic, were evaluated both in vitro and in vivo models. HA·TCP was supposed as a completely biodegradable material and designed as a scaffold to be used for bone reconstruction or regeneration. Materials processing was proposed and physical properties as well as microstructure feature were characterized. Biological postulation of the relationship between seeding density and proliferation, and viability of human osteoblasts cultured on the porous HA·TCP were quantitatively measured. Bone reconstruction was investigated both in vitro and in vivo by using these biodegradable scaffolds with pore sizes ranged in 200400 μm in diameter. The degradable scaffold supported cellular proliferation of seeded osteoblasts on the scaffold and shown normal differentiated function in vitro. Seeding density is an important factor for cell attachment and proliferation expression and has been considerably discussed. Suitable pore size of the scaffolds is required if promotion of bone reconstruction is desired. Clinical trials show that HA·TCP scaffolds are successful applied for bone reconstruction and regeneration and can be completely degraded in human body in 12 months. This approach suggests the feasibility of using porous HA·TCP scaffold materials for the transplantation of autogenous osteoblasts to regenerate bone tissue.展开更多
The wild cotton diploid species (2n = 2x = 26) are important sources of useful traits such as high fiber quality, resistance to biotic and abiotic stresses etc., which can be introgressed into the cultivated tetraploi...The wild cotton diploid species (2n = 2x = 26) are important sources of useful traits such as high fiber quality, resistance to biotic and abiotic stresses etc., which can be introgressed into the cultivated tetraploid cotton <i>Gossypium hirsutum</i> L (2n = 4x = 52), for its genetic improvement. The African wild diploid species <i>G. longicalyx</i> Hutchinson and Lee could be used as donor of the desirable traits of fiber fineness and resistance to reniform nematode. However, hybridization of wild diploid species and cultivated tetraploid cotton encounters a sterility problem of the triploid (2n = 3x = 59), mainly due to ploidy. The restoration of the fertility can be done by creating an allohexaploid (2n = 6x = 78) through the doubling with colchicine of the sterile triploid chromosomes. With this method, a synthetic allohexaploid hybrid (<i>G. hirsutum</i> × <i>G. longicalyx</i>)2 has been obtained. This genotype was studied using phenotypic, cytological and molecular (AFLP) analyses in order to confirm its hybridity and its caryotype, and also to verify the expression of the desirable traits coming from <i>G. longicalyx</i>. The studied genotype showed a quite good level of pollen fertility (83%), and apart from larger seeds and some minor seedling anomalies, most of its morphological characteristics were intermediate between the two parental species. It had 78 chromosomes, proving its hexaploid status. Molecular analysis revealed 136 AFLP loci in this hexaploid, all from <i>G. hirsutum</i> and <i>G. longicalyx</i>, demonstrating its hybrid status. In addition, the hexaploid exhibited the useful traits of <i>G. longicalyx</i> with regard to its remarkable fiber fineness and its high resistance to the reniform nematode. This allohexaploid hybrid constitutes an interesting agronomic material, which can be used as a bridge for the transfer of useful agronomic traits from wild species to varieties of <i>G. hirsutum</i>.展开更多
Many cases of toxicity and mortality either due to accidental or deliberate ingestion of hair dyes were reported in Egypt, Sudan, Israel, Morocco, Saudi Arabia, India and Tunisia. In the field of forensic analytical t...Many cases of toxicity and mortality either due to accidental or deliberate ingestion of hair dyes were reported in Egypt, Sudan, Israel, Morocco, Saudi Arabia, India and Tunisia. In the field of forensic analytical toxicology, the identification and quantification of chemicals are essential in deaths related to intoxication. The aim of the present study is to conduct chemico-analytical characterization of para-phenylenediamine (PPD) based hair dye of (Black stone hair dye, SHD) currently used for dying hear in Egypt, to confirm the identification of its components, that may be potentially toxic on oral or dermal exposure, this study uses comparison between different analytical methods. The applied analytical methods were inductively coupled plasma/MS (ICP/MS), witch used to determine the metal components of the dye, high performance liquid chromatography/MS (HPLC/MS) and gas chromatography/mass spectroscopy (GC/MS) were used for qualitative and quantitative analysis of PPD in the dye. A derivatization method was applied by transforming PPD (aromatic amines) into corresponding imine derivatives. This compound was prepared by condensation of 4-methylbenzeneamine with benzaldehyed to give N-benzylidene-4-methylbenzene-amine, which is a very stable internal standard. ICP/MS analysis revealed that most metal components of hair dye are Be, Na, Al, K, Ca, Sc, Ti, V, Cr, Mn, Fe, Cu, and Zr, where HPLC/MS analysis revealed that PPD is the main ingredient of SHD. Derivatization is necessary for accurate determination of PPD in hair dye by GC/MS method and this results could not be obtained by direct injection of dye (without derivatization).展开更多
文摘Bioactive ceramic scaffolds HA·TCP, aimed to be applied in clinic, were evaluated both in vitro and in vivo models. HA·TCP was supposed as a completely biodegradable material and designed as a scaffold to be used for bone reconstruction or regeneration. Materials processing was proposed and physical properties as well as microstructure feature were characterized. Biological postulation of the relationship between seeding density and proliferation, and viability of human osteoblasts cultured on the porous HA·TCP were quantitatively measured. Bone reconstruction was investigated both in vitro and in vivo by using these biodegradable scaffolds with pore sizes ranged in 200400 μm in diameter. The degradable scaffold supported cellular proliferation of seeded osteoblasts on the scaffold and shown normal differentiated function in vitro. Seeding density is an important factor for cell attachment and proliferation expression and has been considerably discussed. Suitable pore size of the scaffolds is required if promotion of bone reconstruction is desired. Clinical trials show that HA·TCP scaffolds are successful applied for bone reconstruction and regeneration and can be completely degraded in human body in 12 months. This approach suggests the feasibility of using porous HA·TCP scaffold materials for the transplantation of autogenous osteoblasts to regenerate bone tissue.
文摘The wild cotton diploid species (2n = 2x = 26) are important sources of useful traits such as high fiber quality, resistance to biotic and abiotic stresses etc., which can be introgressed into the cultivated tetraploid cotton <i>Gossypium hirsutum</i> L (2n = 4x = 52), for its genetic improvement. The African wild diploid species <i>G. longicalyx</i> Hutchinson and Lee could be used as donor of the desirable traits of fiber fineness and resistance to reniform nematode. However, hybridization of wild diploid species and cultivated tetraploid cotton encounters a sterility problem of the triploid (2n = 3x = 59), mainly due to ploidy. The restoration of the fertility can be done by creating an allohexaploid (2n = 6x = 78) through the doubling with colchicine of the sterile triploid chromosomes. With this method, a synthetic allohexaploid hybrid (<i>G. hirsutum</i> × <i>G. longicalyx</i>)2 has been obtained. This genotype was studied using phenotypic, cytological and molecular (AFLP) analyses in order to confirm its hybridity and its caryotype, and also to verify the expression of the desirable traits coming from <i>G. longicalyx</i>. The studied genotype showed a quite good level of pollen fertility (83%), and apart from larger seeds and some minor seedling anomalies, most of its morphological characteristics were intermediate between the two parental species. It had 78 chromosomes, proving its hexaploid status. Molecular analysis revealed 136 AFLP loci in this hexaploid, all from <i>G. hirsutum</i> and <i>G. longicalyx</i>, demonstrating its hybrid status. In addition, the hexaploid exhibited the useful traits of <i>G. longicalyx</i> with regard to its remarkable fiber fineness and its high resistance to the reniform nematode. This allohexaploid hybrid constitutes an interesting agronomic material, which can be used as a bridge for the transfer of useful agronomic traits from wild species to varieties of <i>G. hirsutum</i>.
文摘Many cases of toxicity and mortality either due to accidental or deliberate ingestion of hair dyes were reported in Egypt, Sudan, Israel, Morocco, Saudi Arabia, India and Tunisia. In the field of forensic analytical toxicology, the identification and quantification of chemicals are essential in deaths related to intoxication. The aim of the present study is to conduct chemico-analytical characterization of para-phenylenediamine (PPD) based hair dye of (Black stone hair dye, SHD) currently used for dying hear in Egypt, to confirm the identification of its components, that may be potentially toxic on oral or dermal exposure, this study uses comparison between different analytical methods. The applied analytical methods were inductively coupled plasma/MS (ICP/MS), witch used to determine the metal components of the dye, high performance liquid chromatography/MS (HPLC/MS) and gas chromatography/mass spectroscopy (GC/MS) were used for qualitative and quantitative analysis of PPD in the dye. A derivatization method was applied by transforming PPD (aromatic amines) into corresponding imine derivatives. This compound was prepared by condensation of 4-methylbenzeneamine with benzaldehyed to give N-benzylidene-4-methylbenzene-amine, which is a very stable internal standard. ICP/MS analysis revealed that most metal components of hair dye are Be, Na, Al, K, Ca, Sc, Ti, V, Cr, Mn, Fe, Cu, and Zr, where HPLC/MS analysis revealed that PPD is the main ingredient of SHD. Derivatization is necessary for accurate determination of PPD in hair dye by GC/MS method and this results could not be obtained by direct injection of dye (without derivatization).
