Chitosan/bovine serum albumin (BSA) ultrathin films were fabricated on modified quartz wafer through layer by layer deposition.The effects of experimental conditions, such as pH value, molecular weight of CS, ionic st...Chitosan/bovine serum albumin (BSA) ultrathin films were fabricated on modified quartz wafer through layer by layer deposition.The effects of experimental conditions, such as pH value, molecular weight of CS, ionic strength and polyanions coexisting in BSA solution, on the fabrication and the stability of films were investigated with a radio\|labeled method. The results show that the absorbed BSA is almost proportional to the number of assembly cycle except the first 2 cycles, and chitosan/BSA films are favorable to be fabricated in chitosan aq AcOH at pH=5.2 as compared with at pH=1.0. When two different molecular weight (MW) chitosans were used ( M η≈1.2×10 5, M η≈1.0×10 6), the lower MW chitosan adsorbs more BSA, but less stable ultrathin films are fabricated. Similar results were obtained that the amount of adsorbed BSA is higher but the films formed are less stable in water than in phosphate buffered saline (PBS). The adsorption of BSA is restricted greatly in the presence of poly(sodium styrene sulfonate) (PSS) mainly because of the competitive adsorption.展开更多
AIM: To determine the tissue and temporal distribution of human umbilical cord matrix stem (hUCMS) cells in severe combined immunodeficiency (SCID) mice. METHODS: For studying the localization of hUCMS cells, tritiate...AIM: To determine the tissue and temporal distribution of human umbilical cord matrix stem (hUCMS) cells in severe combined immunodeficiency (SCID) mice. METHODS: For studying the localization of hUCMS cells, tritiated thymidine-labeled hUCMS cells were injected in SCID mice and tissue distribution was quantitatively determined using a liquid scintillation counter at days 1, 3, 7 and 14. Furthermore, an immunofluorescence detection technique was employed in which anti-human mitochondrial antibody was used to identify hUCMS cells in mouse tissues. In order to visualize the distribution of transplanted hUCMS cells in H&E stained tissue sections, India Black ink 4415 was used to label the hUCMS cells. RESULTS: When tritiated thymidine-labeled hUCMS cells were injected systemically (iv) in female SCID mice, the lung was the major site of accumulation at 24 h after transplantation. With time, the cells migrated to other tissues, and on day three, the spleen, stomach, and small and large intestines were the major accumulation sites. On day seven, a relatively large amount of radioactivity was detected in the adrenal gland, uterus, spleen, lung, and digestive tract. In addition, labeled cells had crossed the blood brain barrier by day 1. CONCLUSION: These results indicate that peripherally injected hUCMS cells distribute quantitatively in a tissue-specific manner throughout the body.展开更多
文摘Chitosan/bovine serum albumin (BSA) ultrathin films were fabricated on modified quartz wafer through layer by layer deposition.The effects of experimental conditions, such as pH value, molecular weight of CS, ionic strength and polyanions coexisting in BSA solution, on the fabrication and the stability of films were investigated with a radio\|labeled method. The results show that the absorbed BSA is almost proportional to the number of assembly cycle except the first 2 cycles, and chitosan/BSA films are favorable to be fabricated in chitosan aq AcOH at pH=5.2 as compared with at pH=1.0. When two different molecular weight (MW) chitosans were used ( M η≈1.2×10 5, M η≈1.0×10 6), the lower MW chitosan adsorbs more BSA, but less stable ultrathin films are fabricated. Similar results were obtained that the amount of adsorbed BSA is higher but the films formed are less stable in water than in phosphate buffered saline (PBS). The adsorption of BSA is restricted greatly in the presence of poly(sodium styrene sulfonate) (PSS) mainly because of the competitive adsorption.
基金Supported by (in part) the Kansas State University (KSU) Terry C. Johnson Center for Basic Cancer Researchthe KSU College of Veterinary Medicine Dean's FundKSU Targeted Excellence, Kansas State Legislative Appropriation and NIH1R21CA135599
文摘AIM: To determine the tissue and temporal distribution of human umbilical cord matrix stem (hUCMS) cells in severe combined immunodeficiency (SCID) mice. METHODS: For studying the localization of hUCMS cells, tritiated thymidine-labeled hUCMS cells were injected in SCID mice and tissue distribution was quantitatively determined using a liquid scintillation counter at days 1, 3, 7 and 14. Furthermore, an immunofluorescence detection technique was employed in which anti-human mitochondrial antibody was used to identify hUCMS cells in mouse tissues. In order to visualize the distribution of transplanted hUCMS cells in H&E stained tissue sections, India Black ink 4415 was used to label the hUCMS cells. RESULTS: When tritiated thymidine-labeled hUCMS cells were injected systemically (iv) in female SCID mice, the lung was the major site of accumulation at 24 h after transplantation. With time, the cells migrated to other tissues, and on day three, the spleen, stomach, and small and large intestines were the major accumulation sites. On day seven, a relatively large amount of radioactivity was detected in the adrenal gland, uterus, spleen, lung, and digestive tract. In addition, labeled cells had crossed the blood brain barrier by day 1. CONCLUSION: These results indicate that peripherally injected hUCMS cells distribute quantitatively in a tissue-specific manner throughout the body.
