AIM: To investigate whether single-nucleotide polymor- phisms in the promoter regions of endotoxin-responsive genes CD14 C (-159) T is associated with chronic hepatitis B. METHODS: We obtained genomic DNA from 80 pati...AIM: To investigate whether single-nucleotide polymor- phisms in the promoter regions of endotoxin-responsive genes CD14 C (-159) T is associated with chronic hepatitis B. METHODS: We obtained genomic DNA from 80 patients with established diagnosis of chronic hepatitis B and 126 healthy subjects served as a control population. The CD 14 C (-159) T polymorphism was investigated using an allele specific PCR method. RESULTS: Twenty seven percent of chronic hepatitis B patients and 75% of controls were heterozygous for CT genotype. The difference between the chronic hepatitis B and control groups was statistically significant [P < 0.0001; Odds ratio (OR) = 2.887; 95% CI: 1.609-5.178]. Twenty four point six percent of chronic hepatitis B and patients 12.3% of the control group were heterozygous for TT genotype. The difference between groups was not statistically significant (P = 0.256; OR = 0.658; 95% CI: 0.319-1.358). Forty eight point four percent of chronic hepatitis B patients and 12.7% of control were homozy- gote for CC genotype (P < 0.004; OR = 0.416; 95% CI: 0.229-0.755). The frequency of allele C was 61.9% and allele T was 38.1% in hepatitis B patients group. The frequency of allele C was 55.2% and allele T was 44.8% for the control group (P = 0.179; OR = 1.319; 95% CI: 0.881-1.977). CONCLUSION: The TT heterozygous genotype was not a risk factor for chronic hepatitis B. CC homozygote genotype is protective for hepatitis B. Lack of heterozy- gosis of genotype CT is a risk factor for chronic hepatitis B. Alleles C or T were not risk factors for chronic hepatitis B. These findings show the role of a single-nucleotide polymorphism at CD14/-159 on the development ofchronic hepatitis B. Endotoxin susceptibility may play a role in the pathogenesis of chronic hepatitis B.展开更多
BACKGROUND： Previous studies have shown that p75 neurotrophin receptor plays an important role in peripheral nerve injury. However, the role of p75 neurotrophin receptor in the regeneration of peripheral nerves remai...BACKGROUND： Previous studies have shown that p75 neurotrophin receptor plays an important role in peripheral nerve injury. However, the role of p75 neurotrophin receptor in the regeneration of peripheral nerves remains poorly understood. OBJECTIVE： To study the effect of p75 neurotrophin receptor on facial nerve regeneration. DESIGN, TIME AND SETTING： A randomized controlled experiment was performed in the Regeneration Laboratory of Flinders University, Australia and the Biomedical Laboratory of Dentistry School, Shandong University from March 2005 to February 2006. MATERIALS： Cholera toxin B subunit, fast blue, and biotin rabbit-anti goat IgG were provided by Sigma, USA; goat-anti choleratoxin B subunit ant/body was provided by List Biologicals, USA. METHODS： In p75 neurotrophin receptor knockout and wild type 129/sv mice, the facial nerves on one side were crushed. At days 2 and 4 following injury, regenerating motor neurons in the facial nuclei were labeled by fast blue, and the regenerating axon was labeled by the anterograde tracer choleratoxin B subunit. MAIN OUTCOME MEASURES： Axonal regenerative velocity and number were detected by immunohistochemical staining of choleratoxin B subunit, growth-associated protein, protein gene product 9.5, and calcitonin-gene-related peptide; survival of motor neurons in the facial nuclei was detected by retrograde fast blue. RESULTS： Axonal growth in the facial nerve of p75 neurotrophin receptor knockout mice was significantly less than in wild type mice. At day 7 after injury, the number of regenerating motor neurons in p75 neurotrophin receptor knockout mice remained significantly less than in wild type mice （P 〈 0.05）. The number of positively stained fibers for growth-associated protein-43, protein gene product 9.5, and calcitonin-gene-related peptide in p75 neurotrophin receptor knockout mice was significantly less than in wild type mice （P 〈 0.01）. CONCLUSION： p75 neurotrophin receptor promoted axonal regeneration and enhanced the survival rate of motor neurons following facial nerve injury.展开更多
Three diphtheria toxin (DT) mutants CRM-197, DT-del (148) and DT-El48S-K516A-F530A were cloned in B- Subtilis plasmid PSM604 under the subtilisin signal sequence. The expression was effective in both SMS300 and SMS118...Three diphtheria toxin (DT) mutants CRM-197, DT-del (148) and DT-El48S-K516A-F530A were cloned in B- Subtilis plasmid PSM604 under the subtilisin signal sequence. The expression was effective in both SMS300 and SMS118, but higher yield of 7. 1 mg/L was observed in SMS300 compared with 2. 1 mg/L in SMS118. Western blot showed that the recombinant protein could be effectively secreted into the culture medium as a 58 ku peptide, and could be de-graded into two peptides of 37ku and 21ku.展开更多
目的构建霍乱弧菌肠毒素B亚单位(Cholera toxin B subunit,CTB)基因的大肠杆菌表达重组质粒,并观察其在大肠杆菌和双歧杆菌中的表达。方法从pBI121质粒PCR扩增获得CTB基因片断,克隆到大肠杆菌载体pGEX-4T-1上,构建重组质粒,然后转化大...目的构建霍乱弧菌肠毒素B亚单位(Cholera toxin B subunit,CTB)基因的大肠杆菌表达重组质粒,并观察其在大肠杆菌和双歧杆菌中的表达。方法从pBI121质粒PCR扩增获得CTB基因片断,克隆到大肠杆菌载体pGEX-4T-1上,构建重组质粒,然后转化大肠杆菌DH5α和双歧杆菌。转化菌经IPTG诱导,然后用SDS-PAGE和Western blot方法鉴定表达的重组蛋白。结果构建了重组质粒pGEX-4T-CTB,CTB基因片段分子量约为376bp;在大肠杆菌中表达出35kD的霍乱弧菌B亚单位融合蛋白,经SDS-PAGE分析,相对分子量与文献相符,表达的蛋白约占细菌总蛋白的10%;在双岐杆菌中也能得到正确表达,表达量较大肠杆菌低,占细菌总蛋白约5%。Western blotting结果确认了该条带为CTB基因的产物。结论构建的重组质粒pGEX-4T-CTB能够在大肠杆菌及双歧杆菌中获得表达。展开更多
文摘AIM: To investigate whether single-nucleotide polymor- phisms in the promoter regions of endotoxin-responsive genes CD14 C (-159) T is associated with chronic hepatitis B. METHODS: We obtained genomic DNA from 80 patients with established diagnosis of chronic hepatitis B and 126 healthy subjects served as a control population. The CD 14 C (-159) T polymorphism was investigated using an allele specific PCR method. RESULTS: Twenty seven percent of chronic hepatitis B patients and 75% of controls were heterozygous for CT genotype. The difference between the chronic hepatitis B and control groups was statistically significant [P < 0.0001; Odds ratio (OR) = 2.887; 95% CI: 1.609-5.178]. Twenty four point six percent of chronic hepatitis B and patients 12.3% of the control group were heterozygous for TT genotype. The difference between groups was not statistically significant (P = 0.256; OR = 0.658; 95% CI: 0.319-1.358). Forty eight point four percent of chronic hepatitis B patients and 12.7% of control were homozy- gote for CC genotype (P < 0.004; OR = 0.416; 95% CI: 0.229-0.755). The frequency of allele C was 61.9% and allele T was 38.1% in hepatitis B patients group. The frequency of allele C was 55.2% and allele T was 44.8% for the control group (P = 0.179; OR = 1.319; 95% CI: 0.881-1.977). CONCLUSION: The TT heterozygous genotype was not a risk factor for chronic hepatitis B. CC homozygote genotype is protective for hepatitis B. Lack of heterozy- gosis of genotype CT is a risk factor for chronic hepatitis B. Alleles C or T were not risk factors for chronic hepatitis B. These findings show the role of a single-nucleotide polymorphism at CD14/-159 on the development ofchronic hepatitis B. Endotoxin susceptibility may play a role in the pathogenesis of chronic hepatitis B.
基金the Natural Science Foundation of Shandong Province,No. Y2008C54
文摘BACKGROUND： Previous studies have shown that p75 neurotrophin receptor plays an important role in peripheral nerve injury. However, the role of p75 neurotrophin receptor in the regeneration of peripheral nerves remains poorly understood. OBJECTIVE： To study the effect of p75 neurotrophin receptor on facial nerve regeneration. DESIGN, TIME AND SETTING： A randomized controlled experiment was performed in the Regeneration Laboratory of Flinders University, Australia and the Biomedical Laboratory of Dentistry School, Shandong University from March 2005 to February 2006. MATERIALS： Cholera toxin B subunit, fast blue, and biotin rabbit-anti goat IgG were provided by Sigma, USA; goat-anti choleratoxin B subunit ant/body was provided by List Biologicals, USA. METHODS： In p75 neurotrophin receptor knockout and wild type 129/sv mice, the facial nerves on one side were crushed. At days 2 and 4 following injury, regenerating motor neurons in the facial nuclei were labeled by fast blue, and the regenerating axon was labeled by the anterograde tracer choleratoxin B subunit. MAIN OUTCOME MEASURES： Axonal regenerative velocity and number were detected by immunohistochemical staining of choleratoxin B subunit, growth-associated protein, protein gene product 9.5, and calcitonin-gene-related peptide; survival of motor neurons in the facial nuclei was detected by retrograde fast blue. RESULTS： Axonal growth in the facial nerve of p75 neurotrophin receptor knockout mice was significantly less than in wild type mice. At day 7 after injury, the number of regenerating motor neurons in p75 neurotrophin receptor knockout mice remained significantly less than in wild type mice （P 〈 0.05）. The number of positively stained fibers for growth-associated protein-43, protein gene product 9.5, and calcitonin-gene-related peptide in p75 neurotrophin receptor knockout mice was significantly less than in wild type mice （P 〈 0.01）. CONCLUSION： p75 neurotrophin receptor promoted axonal regeneration and enhanced the survival rate of motor neurons following facial nerve injury.
文摘Three diphtheria toxin (DT) mutants CRM-197, DT-del (148) and DT-El48S-K516A-F530A were cloned in B- Subtilis plasmid PSM604 under the subtilisin signal sequence. The expression was effective in both SMS300 and SMS118, but higher yield of 7. 1 mg/L was observed in SMS300 compared with 2. 1 mg/L in SMS118. Western blot showed that the recombinant protein could be effectively secreted into the culture medium as a 58 ku peptide, and could be de-graded into two peptides of 37ku and 21ku.
