To investigate the cytogenetic parameters and characterise the chromosomal banding pattern of Tho-Tho cattle, a breed of indigenous cattle found in the Northeastern states of India were reared for meat purpose. Lympho...To investigate the cytogenetic parameters and characterise the chromosomal banding pattern of Tho-Tho cattle, a breed of indigenous cattle found in the Northeastern states of India were reared for meat purpose. Lymphocyte culture technique was carried out in 28 Tho-Tho cattle and culture was harvested for good metaphase spread. Good metaphase spreads were selected for analysis, such as relative length, centromeric index and arm ratio. Centromeric banding （C-banding） and reverse banding （R-banding） methods were done for detail and better understanding of the chromosome morphology. The chromosome number in Tho-Tho cattle was observed to be 2n = 60 in all complete metaphase. The mean relative length of the autosomal chromosomes varied from 5.48% ：~ 0.107% to 1.79% ＋ 0.105% in male and 5.31% ：E 0.148% to 1.86% ＋ 0.055% in female, respectively. The chromosome banding showed C-positive dark band heterochromatin in all the acrocentric autosome. However, in sex chromosome, the Y-chromosome showed negative C-band and also the X-chromosome did not show any stain at the centromeric region. The numbers of R-band pattern were observed to be 490 and 499 band in male and female, respectively. One of the X-chromosome showed light banding pattern, confirming the inactivation during the embryonic development in female. The fundamental chromosome number and banding pattern of Tho-Tho cattle did not vary from the other breed of the Bos indicus. However, it is necessary to start a cytogenetic screening of the Tho-Tho cattle and expand upon more number to be kept at different villages of Nagaland in order to identify animals with chromosomal abnormalities, so that it can be excluded from future breeding strategies for conservation of Tho-Tho genetic resource.展开更多
This research aimed to combine 3 cell and tissue culture technologies to obtain mechanistic insights of cells in porous scaffolds. When cultivated on 2D （2-dimensional） surfaces, HDFs （human dermal fibroblasts） be...This research aimed to combine 3 cell and tissue culture technologies to obtain mechanistic insights of cells in porous scaffolds. When cultivated on 2D （2-dimensional） surfaces, HDFs （human dermal fibroblasts） behaved individually and had no strict requirement on seeding density for proliferation; while HaCat cells relied heavily on initial densities for proliferation and colony formation, which was facilitated when co-cultured with HDFs. Experiments using a 3D CCIS （3-dimensional cell culture and imaging system） indicated that HDFs colonised openpores of varying sizes （125-420 ~tm） on modular substrates via bridge structures; while HaCat cells formed aperture structures and only colonised small pores （125 txm）. When co-cultured, HDFs not only facilitated HaCat attachment on the substrates, but also coordinated with HaCat cells to colonise open pores of varying sizes via bridge and aperture structures. Based on these observations, a 2-stage strategy for the culture of HDFs and HaCat cells on porous scaffolds was proposed and applied successfully on a cellulosic scaffold. This research demonstrated that cell colonisation in scaffolds was dependent on multiple factors; while the integrated 2D＆3D culture technologies and the 3D CCIS was an effective and efficient approach to obtain mechanistic insights of their influences on tissue regeneration.展开更多
Objective:To explore the effects of insulin-like growth factor-1(IGF-1) on migration,proliferation and differentiation of mesenchymal stem cells(MSCs).Methods:MSCs were obtained from Sprague-Dawley rats by a combinati...Objective:To explore the effects of insulin-like growth factor-1(IGF-1) on migration,proliferation and differentiation of mesenchymal stem cells(MSCs).Methods:MSCs were obtained from Sprague-Dawley rats by a combination of gradient centrifugation and cell culture techniques and treated with IGF-1 at concentrations of 5-20 ng/ml.Proliferation of MSCs was determined as the mean doubling time.Expression of CXC chemokine receptor 4(CXCR4) and migration property were determined by flow cytometry and transwell migration essay,respectively.mRNA expression of GATA-4 and collagen II was determined by reverse transcription-polymerase chain reaction(RT-PCR).Results:The mean doubling time of MSC proliferation was decreased,and the expression of CXCR4 on MSCs and migration of MSCs were increased by IGF-1,all in a dose-dependent manner,while the optimal concentration of IGF-1 on proliferation and migration was different.IGF-1 did not affect the expression of GATA-4 or collagen II mRNA.Conclusions:IGF-1 dose-dependently stimulated the proliferation of MSCs,upregulated the expression of CXCR4,and accelerated migration.There was no apparent differentiation of MSCs to cardiomyocytes or chondrocytes after culturing with IGF-1 alone.展开更多
文摘To investigate the cytogenetic parameters and characterise the chromosomal banding pattern of Tho-Tho cattle, a breed of indigenous cattle found in the Northeastern states of India were reared for meat purpose. Lymphocyte culture technique was carried out in 28 Tho-Tho cattle and culture was harvested for good metaphase spread. Good metaphase spreads were selected for analysis, such as relative length, centromeric index and arm ratio. Centromeric banding （C-banding） and reverse banding （R-banding） methods were done for detail and better understanding of the chromosome morphology. The chromosome number in Tho-Tho cattle was observed to be 2n = 60 in all complete metaphase. The mean relative length of the autosomal chromosomes varied from 5.48% ：~ 0.107% to 1.79% ＋ 0.105% in male and 5.31% ：E 0.148% to 1.86% ＋ 0.055% in female, respectively. The chromosome banding showed C-positive dark band heterochromatin in all the acrocentric autosome. However, in sex chromosome, the Y-chromosome showed negative C-band and also the X-chromosome did not show any stain at the centromeric region. The numbers of R-band pattern were observed to be 490 and 499 band in male and female, respectively. One of the X-chromosome showed light banding pattern, confirming the inactivation during the embryonic development in female. The fundamental chromosome number and banding pattern of Tho-Tho cattle did not vary from the other breed of the Bos indicus. However, it is necessary to start a cytogenetic screening of the Tho-Tho cattle and expand upon more number to be kept at different villages of Nagaland in order to identify animals with chromosomal abnormalities, so that it can be excluded from future breeding strategies for conservation of Tho-Tho genetic resource.
文摘This research aimed to combine 3 cell and tissue culture technologies to obtain mechanistic insights of cells in porous scaffolds. When cultivated on 2D （2-dimensional） surfaces, HDFs （human dermal fibroblasts） behaved individually and had no strict requirement on seeding density for proliferation; while HaCat cells relied heavily on initial densities for proliferation and colony formation, which was facilitated when co-cultured with HDFs. Experiments using a 3D CCIS （3-dimensional cell culture and imaging system） indicated that HDFs colonised openpores of varying sizes （125-420 ~tm） on modular substrates via bridge structures; while HaCat cells formed aperture structures and only colonised small pores （125 txm）. When co-cultured, HDFs not only facilitated HaCat attachment on the substrates, but also coordinated with HaCat cells to colonise open pores of varying sizes via bridge and aperture structures. Based on these observations, a 2-stage strategy for the culture of HDFs and HaCat cells on porous scaffolds was proposed and applied successfully on a cellulosic scaffold. This research demonstrated that cell colonisation in scaffolds was dependent on multiple factors; while the integrated 2D＆3D culture technologies and the 3D CCIS was an effective and efficient approach to obtain mechanistic insights of their influences on tissue regeneration.
基金Project supported by the Guangdong Provincial Natural Science Foundation of China (No.8151008901000157)the Scientific Research Fund of Guangdong Province,China (Nos.2008B030301045 and 2011B031800021)the Medical Scientific Research Grant of the Health Ministry of Guangdong Province,China (No. B2011310)
文摘Objective:To explore the effects of insulin-like growth factor-1(IGF-1) on migration,proliferation and differentiation of mesenchymal stem cells(MSCs).Methods:MSCs were obtained from Sprague-Dawley rats by a combination of gradient centrifugation and cell culture techniques and treated with IGF-1 at concentrations of 5-20 ng/ml.Proliferation of MSCs was determined as the mean doubling time.Expression of CXC chemokine receptor 4(CXCR4) and migration property were determined by flow cytometry and transwell migration essay,respectively.mRNA expression of GATA-4 and collagen II was determined by reverse transcription-polymerase chain reaction(RT-PCR).Results:The mean doubling time of MSC proliferation was decreased,and the expression of CXCR4 on MSCs and migration of MSCs were increased by IGF-1,all in a dose-dependent manner,while the optimal concentration of IGF-1 on proliferation and migration was different.IGF-1 did not affect the expression of GATA-4 or collagen II mRNA.Conclusions:IGF-1 dose-dependently stimulated the proliferation of MSCs,upregulated the expression of CXCR4,and accelerated migration.There was no apparent differentiation of MSCs to cardiomyocytes or chondrocytes after culturing with IGF-1 alone.
