[Objective] The effect of different culture conditions on type 5 capsular polysaccharide production of Staphylococcus aureus from diary cattle was studied to provide simple way for CP production and preparation and la...[Objective] The effect of different culture conditions on type 5 capsular polysaccharide production of Staphylococcus aureus from diary cattle was studied to provide simple way for CP production and preparation and laid foundation for carrying out new polysaccharide vaccine research. [Method] Staph-ylococcus aureus was isolated from milk sample of sick dairy cattle and capsular polysaccharide serotypes were identified. Type 5 capsular polysaccharide was cultured on BHI,solid columbia and mod110 culture media. Glucose and lactose were taken as carbon sources for every culture media in solid and liquid state. Therefore 9 different culture conditions were taken to study the effect of culture conditions on capsular polysaccharide production. [Result] Different culture conditions indicated that compared with columbia culture media, BHI culture media could decline capsular polysaccharide production and mod110 culture media could increase capsular polysaccharide production. While for same culture media, solid culture media was better for capsular polysaccharide production,meanwhile,taken lactose as carbon source could increase capsular polysaccharide production.展开更多
AIM: TO estimate the prevalence of the lactase non-persistent genotype (C/C-23910) in a northern Russian population in accordance with ethnicity, and to evaluate self-reported milk consumption depending on lactase ...AIM: TO estimate the prevalence of the lactase non-persistent genotype (C/C-23910) in a northern Russian population in accordance with ethnicity, and to evaluate self-reported milk consumption depending on lactase activity. METHODS: Blood samples for genotyping lactase activity, defining the C/T-13910 variant by polymerase chain reaction, and direct sequencing were taken from 231 medical students of Russian origin aged 17-26 years. We analyzed milk product consumption by questionnaire which was specially designed for the estimation of milk consumption and abdominal complaints. RESULTS: We found that the prevalence of the C/C-13190 genotype in the northern Russian population was 35.6%. The other genotypes nearby C/T-13910 and associated with lactase activity were not present in the study population. The consumption of milk among people with the non-persistent genotype tended to be lower than among the lactose tolerant subjects, but was not statistically significant. CONCLUSION: An investigation of the lactase persistent genotype in a northern Russian population has not been performed before, The genotype did not affect the consumption of milk products in this population which could be explained by low consumption of milk products among the entire study population.展开更多
Objective To explore the strategies which reduce the amount of xenoantigen Galα1, 3 Gal. Methods Human α-galactosidase gene and α1,2-fucosyltransferase gene were transferred into cul-tured porcine vascular endothel...Objective To explore the strategies which reduce the amount of xenoantigen Galα1, 3 Gal. Methods Human α-galactosidase gene and α1,2-fucosyltransferase gene were transferred into cul-tured porcine vascular endothelial cells PEDSV.15 and human α-galactosidase transgenic mice were produced. The Galα1,3Gal on the cell surface and susceptibility of cells to human antibody-mediated lysis were analyzed. Results Human α-galactosidase gene alone reduced 78% of Galα1,3Gal on PEDSV.15 cell surface while human α-galactosidase combined with α1,2-fucosyltransferase genes removed Galα1,3Gal completely. Decrease of Galα1,3Gal could reduce susceptibility of cells to human antibody-mediated lysis, especially during co-expression of α-galactosidase gene and α1,2-fucosyltransferase gene. RT-PCR indicated positive human α-galactosidase gene expression in all organs of positive human α-galacto-sidase transgenic F1 mice including heart, liver, kidney, lung, and spleen, the amount of Galα1,3Gal antigens on which was reduced largely. 58% of spleen cells from F1 mice were destroyed by comp-lement-mediated lysis compared with 24% of those from normal mice. Conclusions Human α-galactosidase gene and α1,2-fucosyltransferase gene effectively reduce the expression of Galα1,3Gal antigens on endothelial cell surface and confers resistance to human serum-mediated cytolysis. The expression of human α-galactosidase in mice can also eliminate the Galα1,3Gal antigens in most tissues and decrease the susceptibility of spleen cells to human serum-mediated cytolysis.展开更多
Our objective is to solve the lactose malabsorption and intolerance of human beings by combining micro-ecology path with genetic engineering technique. Plasmid pMG36e was used to clone and express a β-galactosidase g...Our objective is to solve the lactose malabsorption and intolerance of human beings by combining micro-ecology path with genetic engineering technique. Plasmid pMG36e was used to clone and express a β-galactosidase gene from L. delbrueckü bulgaricus strain 1.1480 in the Lactococcus lactis subsp. cremoris MG1363 and Lactococcus lactis subsp. lactis IL1403. The recombinant plasmid was preserved and proliferated in Escherichia coli ( E. coli) JM109, and transformed into MG1363 and IL1403 by electroporation. The protein expression was studied. ( 1 ) The bifidobacterium culture medium ( BBL) was suitable for the growth of the strain 1.1480. (2) With 13 amino acids at the N-terminus from the vector, β-gal- actosidase fusion protein (which retained the enzyme activity) could be successfully expressed in E. coli JM109, MG1363 and IL1403, but the expression quantity was larger in the former than in the latter two. (3) The SD sequence designed could be successfully recognized by both the E. coli and the Lactococcus lactis, but the expression level of the non-fusion β-galac- tosidase protein was lower than that of the fusion protein in the same host. The β-galactosidase genetically engineered E. coli JM109 is a useful tool to produce this enzyme in vitro . The signal peptide of the usp45 protein from the Lactococcus lac- tis can be added before the promoter sequence to promote β-galactosidase secretion from Lactococcus lactis . The potential ap- plication of the β-galactosidase genetically engineered MG1363 and IL1403 to cure the lactose malabsorption and lactose in- tolerance in both health food and medicine is promising.展开更多
AIM: To study milk consumption and subjective milk- related symptoms in adults genotyped for adult-type hypolactasia. METHODS: A total of 1900 Finnish adults were genotyped for the C/T-13910 variant of adult-type hypo...AIM: To study milk consumption and subjective milk- related symptoms in adults genotyped for adult-type hypolactasia. METHODS: A total of 1900 Finnish adults were genotyped for the C/T-13910 variant of adult-type hypolactasia and filled in a structured questionnaire concerning milk consumption and gastrointestinal problems. RESULTS: The C/C-13910 genotype of adult-type hypolactasia was present in 18% of the study population. The prevalence of the C/C-13910 genotype was higher among subjects who were undergoing investigations because of abdominal symptoms (24%, P < 0.05). Those with the C/C-13910 genotype drank less milk than subjects with either the C/T-13910 or the T/T-13910 genotype of lactase persistence (18% vs 38%; 18% vs 36%, P < 0.01). Subjects with the C/C-13910 genotype had experienced more gastrointestinal symptoms (84%) during the preceding three-month period than those with the C/T-13910 (79%, P < 0.05) or the T/T-13910 genotype (78 %, P < 0.05). Only 9% (29/338) of the subjects with the C/C-13910 genotype consumed milk and reported no symptoms from it.CONCLUSION: Gastrointestinal symptoms are more common among adults with the C/C-13910 genotype of adult-type hypolactasia than in those with genotypes of lactase persistence.展开更多
Sugar beet tops including leaves and crown harvested and chopped into 3-6 cm, mixed with sugar cane pulp and sugar cane molasses (about 5% of the total mass) to provide a mixture contained 30-35 percent dry mater. A...Sugar beet tops including leaves and crown harvested and chopped into 3-6 cm, mixed with sugar cane pulp and sugar cane molasses (about 5% of the total mass) to provide a mixture contained 30-35 percent dry mater. After two months of ensiling, the silage was evaluated and used in the ration of lactating buffaloes. A Latin square experiment in a changeover design, with three periods of time, each with 20 days for adaptation and 10 days for recording data, was conducted in which 15 multiparous lactating buffloes were used in three similar groups, each with five animals. The prepared silage was included in the diet of lactating buffaloes where a control diet (A) was compared with treatment diets contained 25% (B) and 50% (C) silage (DM basis) respectively. Milk yield was recorded, sampled and analysed for fat, protein, solid not-fat and total solids-content. The maximum daily rough milk yield per animal was obtained on diet C while minimum on diet A (P 〈 0.05). Similar trends were observed for 4% fat corrected milk, and 3.5% fat corrected milk that were significantly different between the treatments (P 〈 0.05). The percentage of crude fat and daily fat yield per animal were significantly (P 〈 0.05) higher in treatment C comparing to A and B. An increasingly trend of milk and fat yield was observed when the animals received silage contained diets but statistically it was significant only for the diets contained 50% silage. In addition, the fat percentage was significantly (P 〈 0.05) increased when the buffaloes received diet containing 50% silage. The highest (P 〈 0.05) amount of protein and total solid yield obtained, when the animals received high (50%) silage diet.展开更多
基金Supported by the National Natural Science Foundation of China(30771596)~~
文摘[Objective] The effect of different culture conditions on type 5 capsular polysaccharide production of Staphylococcus aureus from diary cattle was studied to provide simple way for CP production and preparation and laid foundation for carrying out new polysaccharide vaccine research. [Method] Staph-ylococcus aureus was isolated from milk sample of sick dairy cattle and capsular polysaccharide serotypes were identified. Type 5 capsular polysaccharide was cultured on BHI,solid columbia and mod110 culture media. Glucose and lactose were taken as carbon sources for every culture media in solid and liquid state. Therefore 9 different culture conditions were taken to study the effect of culture conditions on capsular polysaccharide production. [Result] Different culture conditions indicated that compared with columbia culture media, BHI culture media could decline capsular polysaccharide production and mod110 culture media could increase capsular polysaccharide production. While for same culture media, solid culture media was better for capsular polysaccharide production,meanwhile,taken lactose as carbon source could increase capsular polysaccharide production.
基金The Sigrid Jusélius Foundation,Helsinki,Finland and Tampere University Hospital Research Funds
文摘AIM: TO estimate the prevalence of the lactase non-persistent genotype (C/C-23910) in a northern Russian population in accordance with ethnicity, and to evaluate self-reported milk consumption depending on lactase activity. METHODS: Blood samples for genotyping lactase activity, defining the C/T-13910 variant by polymerase chain reaction, and direct sequencing were taken from 231 medical students of Russian origin aged 17-26 years. We analyzed milk product consumption by questionnaire which was specially designed for the estimation of milk consumption and abdominal complaints. RESULTS: We found that the prevalence of the C/C-13190 genotype in the northern Russian population was 35.6%. The other genotypes nearby C/T-13910 and associated with lactase activity were not present in the study population. The consumption of milk among people with the non-persistent genotype tended to be lower than among the lactose tolerant subjects, but was not statistically significant. CONCLUSION: An investigation of the lactase persistent genotype in a northern Russian population has not been performed before, The genotype did not affect the consumption of milk products in this population which could be explained by low consumption of milk products among the entire study population.
文摘Objective To explore the strategies which reduce the amount of xenoantigen Galα1, 3 Gal. Methods Human α-galactosidase gene and α1,2-fucosyltransferase gene were transferred into cul-tured porcine vascular endothelial cells PEDSV.15 and human α-galactosidase transgenic mice were produced. The Galα1,3Gal on the cell surface and susceptibility of cells to human antibody-mediated lysis were analyzed. Results Human α-galactosidase gene alone reduced 78% of Galα1,3Gal on PEDSV.15 cell surface while human α-galactosidase combined with α1,2-fucosyltransferase genes removed Galα1,3Gal completely. Decrease of Galα1,3Gal could reduce susceptibility of cells to human antibody-mediated lysis, especially during co-expression of α-galactosidase gene and α1,2-fucosyltransferase gene. RT-PCR indicated positive human α-galactosidase gene expression in all organs of positive human α-galacto-sidase transgenic F1 mice including heart, liver, kidney, lung, and spleen, the amount of Galα1,3Gal antigens on which was reduced largely. 58% of spleen cells from F1 mice were destroyed by comp-lement-mediated lysis compared with 24% of those from normal mice. Conclusions Human α-galactosidase gene and α1,2-fucosyltransferase gene effectively reduce the expression of Galα1,3Gal antigens on endothelial cell surface and confers resistance to human serum-mediated cytolysis. The expression of human α-galactosidase in mice can also eliminate the Galα1,3Gal antigens in most tissues and decrease the susceptibility of spleen cells to human serum-mediated cytolysis.
文摘Our objective is to solve the lactose malabsorption and intolerance of human beings by combining micro-ecology path with genetic engineering technique. Plasmid pMG36e was used to clone and express a β-galactosidase gene from L. delbrueckü bulgaricus strain 1.1480 in the Lactococcus lactis subsp. cremoris MG1363 and Lactococcus lactis subsp. lactis IL1403. The recombinant plasmid was preserved and proliferated in Escherichia coli ( E. coli) JM109, and transformed into MG1363 and IL1403 by electroporation. The protein expression was studied. ( 1 ) The bifidobacterium culture medium ( BBL) was suitable for the growth of the strain 1.1480. (2) With 13 amino acids at the N-terminus from the vector, β-gal- actosidase fusion protein (which retained the enzyme activity) could be successfully expressed in E. coli JM109, MG1363 and IL1403, but the expression quantity was larger in the former than in the latter two. (3) The SD sequence designed could be successfully recognized by both the E. coli and the Lactococcus lactis, but the expression level of the non-fusion β-galac- tosidase protein was lower than that of the fusion protein in the same host. The β-galactosidase genetically engineered E. coli JM109 is a useful tool to produce this enzyme in vitro . The signal peptide of the usp45 protein from the Lactococcus lac- tis can be added before the promoter sequence to promote β-galactosidase secretion from Lactococcus lactis . The potential ap- plication of the β-galactosidase genetically engineered MG1363 and IL1403 to cure the lactose malabsorption and lactose in- tolerance in both health food and medicine is promising.
基金the Sigrid Jusélius Foundation, Helsinki, Finlandthe Foundation for Nutrition Research, Helsinki, Finland+3 种基金the Research Foundation of Alfred Kordelin, Helsinki, FinlandHelsinki University Hospital Research Funding, Helsinki, Finlandthe Foundation for Promoting Occupational Medicine in Finland,Helsinki,Finlandthe Academy of Finland
文摘AIM: To study milk consumption and subjective milk- related symptoms in adults genotyped for adult-type hypolactasia. METHODS: A total of 1900 Finnish adults were genotyped for the C/T-13910 variant of adult-type hypolactasia and filled in a structured questionnaire concerning milk consumption and gastrointestinal problems. RESULTS: The C/C-13910 genotype of adult-type hypolactasia was present in 18% of the study population. The prevalence of the C/C-13910 genotype was higher among subjects who were undergoing investigations because of abdominal symptoms (24%, P < 0.05). Those with the C/C-13910 genotype drank less milk than subjects with either the C/T-13910 or the T/T-13910 genotype of lactase persistence (18% vs 38%; 18% vs 36%, P < 0.01). Subjects with the C/C-13910 genotype had experienced more gastrointestinal symptoms (84%) during the preceding three-month period than those with the C/T-13910 (79%, P < 0.05) or the T/T-13910 genotype (78 %, P < 0.05). Only 9% (29/338) of the subjects with the C/C-13910 genotype consumed milk and reported no symptoms from it.CONCLUSION: Gastrointestinal symptoms are more common among adults with the C/C-13910 genotype of adult-type hypolactasia than in those with genotypes of lactase persistence.
文摘Sugar beet tops including leaves and crown harvested and chopped into 3-6 cm, mixed with sugar cane pulp and sugar cane molasses (about 5% of the total mass) to provide a mixture contained 30-35 percent dry mater. After two months of ensiling, the silage was evaluated and used in the ration of lactating buffaloes. A Latin square experiment in a changeover design, with three periods of time, each with 20 days for adaptation and 10 days for recording data, was conducted in which 15 multiparous lactating buffloes were used in three similar groups, each with five animals. The prepared silage was included in the diet of lactating buffaloes where a control diet (A) was compared with treatment diets contained 25% (B) and 50% (C) silage (DM basis) respectively. Milk yield was recorded, sampled and analysed for fat, protein, solid not-fat and total solids-content. The maximum daily rough milk yield per animal was obtained on diet C while minimum on diet A (P 〈 0.05). Similar trends were observed for 4% fat corrected milk, and 3.5% fat corrected milk that were significantly different between the treatments (P 〈 0.05). The percentage of crude fat and daily fat yield per animal were significantly (P 〈 0.05) higher in treatment C comparing to A and B. An increasingly trend of milk and fat yield was observed when the animals received silage contained diets but statistically it was significant only for the diets contained 50% silage. In addition, the fat percentage was significantly (P 〈 0.05) increased when the buffaloes received diet containing 50% silage. The highest (P 〈 0.05) amount of protein and total solid yield obtained, when the animals received high (50%) silage diet.