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基于分子结构评价的Bacillus subtilis β-1,4-内切木聚糖酶胰蛋白酶抗性的理性设计 被引量:1
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作者 虞晓丹 吴秀秀 +2 位作者 姚冬生 刘大岭 谢春芳 《中国生物工程杂志》 CAS CSCD 北大核心 2016年第8期80-88,共9页
饲料用酶在饲喂过程中,不可避免地会受到消化道中蛋白酶的破坏而令其使用效率受到影响,因此,饲料酶的蛋白酶抗性是其十分重要的性质之一。基于酶反应原理与计算化学理论对Bacillus subtilis 168β-1,4-内切木聚糖酶(Xyn A)的胰蛋白酶抗... 饲料用酶在饲喂过程中,不可避免地会受到消化道中蛋白酶的破坏而令其使用效率受到影响,因此,饲料酶的蛋白酶抗性是其十分重要的性质之一。基于酶反应原理与计算化学理论对Bacillus subtilis 168β-1,4-内切木聚糖酶(Xyn A)的胰蛋白酶抗性进行理性设计,最终得到三个突变体——Xyn A^(R121C)、Xyn A^(R121C/K98Q)和Xyn A^(K39I)。酶学性质分析显示Xyn A^(R121C)和Xyn A^(R121C/K98Q)与野生型(Xyn A)的最适反应温度均为60℃,Xyn A^(K39I)为40℃;突变体酶与野生型酶的最适p H都是6.0;人工肠液(p H 6.8,10 mg/ml胰蛋白酶溶液)处理野生型及其突变体后,Xyn A^(R121C/K98Q)和Xyn A^(R121C)的残留酶活力均明显比野生型高,它们的半衰期分别是野生型的2.02倍和1.52倍,Xyn A^(K39I)在胰蛋白酶溶液中的半衰期为90min,比野生型缩短了37 min。 展开更多
关键词 设计 木聚糖酶 胰蛋白酶抗性 酶稳定
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On the Role of Intestinal Microbiota in Patients with Cognitive Decline
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作者 Friedrich Leblhuber Barbara Strassert +3 位作者 Kostja Steiner Johanna Gostner Burkhard Schuetz Dietmar Fuchs 《Journal of Pharmacy and Pharmacology》 2017年第9期648-653,共6页
Objective: The association between gut microbiota composition and biomarkers of immune activation and inflammation was assessed in the elderly. Patients: Serum inflammation markers of fifty-five outpatients (29 fem... Objective: The association between gut microbiota composition and biomarkers of immune activation and inflammation was assessed in the elderly. Patients: Serum inflammation markers of fifty-five outpatients (29 females, 26 males, aged 78 + 8.5 years) were analyzed. Stool specimens and thus data on gut microbiota were available from a subgroup of 23 individuals (9 females and 14 males). Results: Global cerebral atrophy was found in all magnet resonance tomography scans. Mean mini-mental-score examination in Alzheimer's disease patients was 18.8 ± 7.1, in patients with mild cognitive impairment 27.8 ± 1.5. Serum neopterin concentrations correlated with concentrations of fecal S100A12 (p 〈 0.001) and cq-antitrypsin (p 〈 0.05). Faecalibacterium prausnitzii correlated with MMSE (p 〈 0.05), with Akkermansia muciniphila (p 〈 0.01) and with serum neopterin (p 〈 0.05). Fecal zonulin correlated inversely with Clostridium cluster I (p 〈 0.02). Conclusions: Our results underline earlier in vitro and animal studies that cognitive decline associates with age-related changes in the intestinal microbiota and neuroinflammation. However, only correlational evidence can be reported, and a causative relationship still has to be demonstrated. 展开更多
关键词 MICROBIOTA brain-gut axis PREVENTION cognitive decline.
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α_1-ANTITRYPSIN ATTENUATES ENDOTOXIN-INDUCED ACUTE LUNG INJURY IN RABBITS
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作者 揭志军 蔡映云 +3 位作者 杨文兰 金美玲 朱威 祝慈芳 《Journal of Shanghai Second Medical University(Foreign Language Edition)》 2003年第2期71-76,共6页
Objective To investigate whether pretreatment with α 1-AT can attenuate acute lung injury (ALI) in rabbits induced with endotoxin. Methods Thirty-two New Zealand rabbits were randomly assigned to four groups(n=8):1.I... Objective To investigate whether pretreatment with α 1-AT can attenuate acute lung injury (ALI) in rabbits induced with endotoxin. Methods Thirty-two New Zealand rabbits were randomly assigned to four groups(n=8):1.Infusion of endotoxin(Lipopolysaccharide,LPS 500μg/kg)without α 1-AT (group LPS).2.Infusion α 1-AT 120mg/kg at 15min before challenge with LPS(group LAV).3.Infusion of α 1-AT 120mg/kg(group AAT).4 Infusion of saline 4ml/kg as control (group NS).Arterial blood gases,peripheral leukocyte counts and airway pressure were recorded every 1h.Physiologic intrapulmonary shunting (Qs/Qt) was measured every 4h.After 8h the bloods were collected for measurement of plasma concentration and activity of α 1-AT.Then bronchoalveolar lavage fluid (BALF)was collected for measurement of concentrations of total protein (TP),interleukin-8(IL-8),tumor necrosis factor(TNF-α),the activities of elastase-like and α 1-AT,total phospholipids(TPL) and disaturated phosphatidylcholine (DSPC).In addition,the wet-to-dry lung weight ratio(W/D) was measured. Results After infusion of endotoxin,it was observed that PaO 2,peripheral luekocyte counts,total respiratory compliance progressively decreased and P peak and Qs/Qt increased comparing with the baseline values.In contrast to group NS,the increased plasma concentration but reduced activity of α 1-AT was found in group LPS.In the BALF,the activity of α 1-AT,TPL,DSPC/TPL were lower,but the concentrations of albumin,IL-8,TNF-α,and the activity of NE were higher.The ratio of W/D also increased.The pretreatment of α 1-AT attenuated the deterioration of oxygenation,the reduction of compliance and the deterioration of other physiological,biochemical parameters mentioned above. Conclusion Pretreatment with α 1-AT could attenuate endotoxin-induced lung injury in rabbits.Those beneficial effects of α 1-AT might be due in part to the inhibitory effect on neutrophil elastase. 展开更多
关键词 acute lung injury α 1-antitrypsin neutrophil elastase endotoxin
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Alpha-1 Antitrypsin Deficiency Family Study
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作者 Osorio, Raquel Femandes, Helena +2 位作者 Cafofo Tomasia Clemente, Helena Fialho, Licinio 《Journal of Life Sciences》 2016年第7期321-323,共3页
According to the latest World Health Organization report 64 million people suffer from Chronic Obstructive Pulmonary Disease (COPD), 3 million people died from COPD and it is predicted that COPD will become the thir... According to the latest World Health Organization report 64 million people suffer from Chronic Obstructive Pulmonary Disease (COPD), 3 million people died from COPD and it is predicted that COPD will become the third leading cause of death worldwide by 2030. The alpha-1 antitrypsin deficiency is a rarely diagnosed hereditary disease caused by a genetic mutation and it is one of the most prevalent genetic disorders primarily affecting the lungs, especially in the form of COPD or emphysema, but in some cases also the liver or skin. The Global Initiative for Chronic Obstructive Lung Disease recommends all patients with COPD at a young age or significant family history to be examined for alpha-1 antitrypsin deficiency. This article presents the case of a 42 year old, female patient, Portuguese, with history of Chronic Obstructive Pulmonary Disease, 40 pack units/year smoker, with unknown family history, coming to her family doctor with breath shortness, especially during physical activities, with unsatisfying response to pharmacological prescribed therapy. Physical examination was normal. Alpha- 1 antitrypsin deficiency was confirmed by blood testing. All patient's first degree relatives were investigated showing low alpha-1 antitrypsin blood concentrations thus genetic tests were later performed. This case reinforces the need for primary care physicians to be aware of alphal-antitrypsin deficit as an underdiagnosed clinical entity. 展开更多
关键词 Alpha-1 antitrypsin deficiency Chronic Obstructive Pulmonary Disease family study.
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Alpha 1-antitrypsin and alpha 1-acid glycoprotein reduce the sensitivity of human dermal fibroblast to endotoxin 被引量:1
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作者 夏照帆 王光毅 +1 位作者 葛绳德 田建广 《Chinese Journal of Traumatology》 CAS 2001年第4期199-203,共5页
Objective: To test the hypothesis that acute phase reactants, such as alpha 1-antitrypsin and alpha 1-acid glycoprotein, could protect mammalian cells from further damage. Methods: Human dermal fibroblasts (5×10 ... Objective: To test the hypothesis that acute phase reactants, such as alpha 1-antitrypsin and alpha 1-acid glycoprotein, could protect mammalian cells from further damage. Methods: Human dermal fibroblasts (5×10 4) were cultured with DMEM plus 10% FBS at 37℃ in a 5% CO 2 incubator. Different doses of LPS (lipopolysaccharide) and/or acute phase reactants were added. After 24 hours, the cultured supernatant was aspirated, the cells were washed, fixed and stained by methylene blue. The unbound stain was washed off. The stained cells were solubilized in 0.1 ml of 1% Triton X-100. The absorbance of each well was measured using an ELISA spectrophotometer. The concentration of LPS which decreased the absorbance to 70% of the control (LPS-free) cultures was defined as LD 30. Results: In order to achieve LD 30 in the presence of acute phase proteins, it was necessary to alter the LPS concentrations. The LD 30 of LPS treated with 0, 0.5, 2, 10 mg/ml antitrypsin and 0, 0.5, 2, 10 mg/ml glycoprotein was 5.4, 6.5, 7.6, 14.2 mg/ml and 5.2, 5.9, 6.9, 10.5 mg/ml, respectively. Statistically, with the treatment of more than 2 mg/ml antitrypsin or glycoprotein, LD 30 increased significantly. Conclusions: Our data show that fibroblasts are susceptible to the direct toxicity of LPS. Alpha 1-antitrypsin and alpha 1-acid glycoprotein can reduce the toxicity and/or increase the tolerance of mammalian cells to LPS. 展开更多
关键词 ENDOTOXINS Acute-phase reaction Fibroblasts Alpha 1-antitrypsin OROSOMUCOID
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