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31.
《Pancreatology》2014,14(5):356-360
ObjectivesTo evaluate the relationship between exocrine pancreatic insufficiency and the level of glycemic control in diabetes (DM).MethodsPatients with type 2 DM treated in our clinic were prospectively recruited into the study. Pancreatic diabetes was excluded. Cases with HbA1c ≥7% formed Group A (n = 59), and with HbA1c <7% Group B (n = 42). The fecal level of pancreatic elastase (PE-1) was measured and morphological examinations of the pancreas were performed.ResultsThe PE-1 level was significantly lower in Group A than in Group B (385.9 ± 171.1 μg/g, vs. 454.6 ± 147.3 μg/g, p = 0.038). The PE-1 level was not correlated with HbA1c (r = −0.132, p = 0.187), the duration of DM (r = −0.046, p = 0.65), age (r = 0.010, p = 0.921), BMI (r = 0.203, p = 0.059), or pancreatic steatosis (r = 0.117, p = 0.244). The size of the pancreas did not differ significantly between Groups A and B.ConclusionsAn exocrine pancreatic insufficiency demonstrated by fecal PE-1 determination is more frequent in type 2 DM patients with poor glycemic control. The impaired exocrine pancreatic function cannot be explained by an alteration in the size of the pancreas or by pancreatic steatosis.  相似文献   
32.
目的研究胆汁内外引流方法对梗阻性黄疸大鼠肺肿瘤坏死因子α(TNF-α)、中性粒细胞弹性蛋白酶(NE)水平的影响。方法将64只成年SD雄性大鼠随机分为4组,分别建立梗阻性黄疸(OJ)、胆汁内引流术(ID)、胆汁外引流术(ED)及假手术(SH)4组模型。于2次术后第14天留取肺组织匀浆液标本。采用双抗体夹心酶联免疫吸附法(ELISA)检测10%肺匀浆液TNF-α水平,生化法检测10%肺匀浆液NE水平。结果成功建立了大鼠梗阻性黄疸及内外引流术模型。梗阻性黄疸时大鼠肺TNF-α、NE水平较假手术对照组明显升高(100.893 pg/mL±21.271 pg/mL vs 64.091 pg/mL±13.034 pg/mL,P<0.01;50.396μg/mL±17.388μg/mL vs 39.718μg/mL±9.625μg/mL,P<0.05)。通过胆汁内引流术解除黄疸后,大鼠肺TNF-α浓度(75.141 pg/mL±15.849 pg/mL)与梗阻性黄疸组相比下降明显(P<0.01);而通过胆汁外引流术解除黄疸后,大鼠肺TNF-α浓度仍较高(112.129 pg/mL±36.886 pg/mL),与梗阻性黄疸组相比无差异(P>0.05)。行胆汁内、外引流术后,大鼠肺NE水平均降低(39.390μg/mL±12.410μg/mL、44.790μg/mL±16.681μg/mL),但与梗阻性黄疸组相比内引流明显(P<0.05)、外引流无差异(P>0.05),且内引流恢复至正常水平,与假手术对照组相比无差异(P>0.05)。结论梗阻性黄疸可导致肺组织炎症细胞因子升高,胆汁内引流术可明显改善梗阻性黄疸时肺组织炎症细胞因子水平、甚至接近正常,而胆汁外引流术没有改善肺炎症细胞因子水平,提示术前利用胆汁内引流术解除梗阻性黄疸缓解肺部炎症反应优于外引流术。  相似文献   
33.

Introduction

Post-cardiac arrest syndrome (PCAS) is often associated with disseminated intravascular coagulation (DIC), thus leading to the development of multiple organ dysfunction syndrome (MODS). The aim of this study was to examine the pathophysiological relationships between coagulation, fibrinolysis and fibrinolytic shutdown by evaluating the levels of coagulofibrinolytic markers, including soluble fibrin, thrombin-activatable fibrinolysis inhibitor (TAFI), tissue plasminogen activator-plasminogen activator inhibitor-1 complex (tPAIC), plasmin-alpha2 plasmin inhibitor complex (PPIC), neutrophil elastase and fibrin degradation product by neutrophil elastase (EXDP).

Materials and Methods

Fifty-two resuscitated patients were divided into two groups: 22 DIC and 30 non-DIC patients.

Results

The levels of soluble fibrin, PPIC, tPAIC, EXDP and neutrophil elastase in the DIC patients with PCAS were significantly higher than those observed in the non-DIC patients. The values of the tPAIC and JAAM DIC scores were found to be independent predictors of increased SOFA scores in the DIC patients. The MODS patients demonstrated significantly higher levels of soluble fibrin and tPAIC; however, the levels of TAFI and EXDP were identical between the patients with and without MODS. In addition, positive correlations were observed between the levels of tPAIC and EXDP in the patients with non-MODS; however, no correlations were observed between these markers in the MODS patients.

Conclusions

Thrombin activation and fibrinolytic shutdown play important roles in the development of organ dysfunction in PCAS patients. Neutrophil elastase-mediated fibrinolysis cannot overcome the fibrinolytic shutdown that occurs in DIC patients with PCAS, thus resulting in the development of MODS.  相似文献   
34.
An automated assay of plasma prekallikrein is described. Prekallikrein was converted to kallikrein with Pseudomonas aeruginosa elastase, and the hydrolytic activity of kallikrein to H-D-Pro-Phe-Arg-paranitroanilide subsequently measured.

The conversion was complete within 8 minutes and the amidolytic activity remained stable at least another 10 min at 37 ° C. This method worked in plasma deficient in Hageman factor (blood coagulation factor XII). Using anti-prekallikrein antibody and plasma deficient in prekallikrein, the amidolytic activity generated in normal plasma was identified as due to kallikrein. With plasma samples, the coefficients of variation (CV) for multiple measurements within run (n = 10) and between run (n = 10) were as low as 5.0% and 6.6%, respectively, and the minimum measurable concentration of prekallikrein in plasma was 10% of the normal level.  相似文献   

35.
Effector functions of the elastin receptor on human phagocytic cells from young and older individuals were studied. In cells of young healthy subjects the elastin peptides, the agonists of receptor, stimulated both superoxide anion release from PMNs and phagocytosis of coated human red cells by monocytes. Elastin appeared to inhibit the cholesterol synthesis in monocytes, measured by the incorporation of 14C-acetate. In comparison with phagocytic cells of young (≤25 ± 6 years) subjects, PMNs of elderly donors (≥75 ±10 years) bore a similar number of binding sites for soluble elastin peptides, and the affinity of the elastin receptor was unchanged as shown by Scatchard analysis. The phagocytosis of coated human red cells stimulated by elastin peptides was also similar in the two age groups. However, several differences were found between phagocytic cells of young and elderly donors 1) PMNs of elderly released increased amounts of elastase from both resting and elastin peptide stimulated cells, and 2) monocytes of elderly showed a lack of inhibition of cholesterol synthesis by elastin peptides when maintained in cholesterol-free medium. These changes in effector functions of phagocytic cells from elderly donors might contribute to the age-dependent increase of susceptibility to the development of atherosclerotic lesions.  相似文献   
36.
Proteases play a critical role in the ordered remodelling of extracellular matrix (ECM) components during wound healing and tissue regeneration. However, the usually ordered proteolysis is compromised in chronic wounds due to over‐expression and high concentrations of matrix metalloproteinase's (MMPs) and neutrophil elastase (NE). Ovine forestomach matrix (OFM) is a decellularised extracellular matrix‐based biomaterial developed for tissue regeneration applications, including the treatment of chronic wounds, and is a heterogeneous mixture of ECM proteins and proteoglycans that retains the native structural and functional characteristics of tissue ECM. Given the diverse molecular species present in OFM, we hypothesised that OFM may contain components or fragments that inhibit MMP and NE activity. An extract of OFM was shown to be a potent inhibitor of a range of tissue MMPs (IC50s = 23 ± 5 to 115 ± 14 µg/ml) and NE (IC50 = 157 ± 37 µg/ml), and was more potent than extracts prepared from a known protease modulating wound dressing. The broad spectrum activity of OFM against different classes of MMPs (i.e. collagenases, gelatinases and stromelysins) may provide a clinical advantage by more effectively addressing the protease imbalance seen in chronic wounds.  相似文献   
37.
[目的]通过检测急性心肌梗死(AMI)、不稳定心绞痛(UAP)、稳定心绞痛(SAP)、陈旧性心肌梗死(OMI)、正常人、慢性支气管炎患者的中性粒细胞弹性蛋白酶(NE)浓度,以探讨NE与ACS、冠心病病情严重程度的关系。[方法]根据病史、体检、心电图、胸片、彩色多普勒的结果,139名患者分成ACS组(A组)、冠脉病变稳定状态组(B组),慢性炎症对照组为慢性支气管炎组(C组),正常对照组为正常人组(D组)。ACS患者在发病后24h抽取静脉血,其余患者在入院后立即抽取静脉血,行血常规和肌钙蛋白、肌酸磷酸激酶检查,并立即分离血浆,-40℃保存至检测。PMNElastaseKit试剂盒以酶联免疫吸附检测法(ELISA)检测患者血浆中NE浓度。[结果]①A组NE浓度明显高于B组、C组、D组,差别有统计学意义(χ2=34.503,P﹤0.0001);B、C、D组间差异无统计学意义(P﹥0.05)。②NE浓度与肌钙蛋白、肌酸磷酸激酶、白细胞总数和中性粒细胞百分比值均呈正相关(P﹤0.001),与高血压、糖尿病和高脂血症无相关性(P﹥0.05);同时,A组与C组白细胞总数(WBC)和中性粒细胞百分比值(N)进行比较,两组差异无统计学意义(P﹥0.05)。③比较同一患者在急性期和稳定期所测得NE的浓度,发现急性期组与稳定期组NE浓度差异有统计学意义(t=3.121,P﹤0.005),从而更进一步证实NE浓度在冠心病不稳定期高于稳定期。[结论]血浆NE浓度与急性冠脉病变不稳定状态有相关性,可能是冠状动脉斑块病变不稳定性的炎性标志物之一。  相似文献   
38.
ABSTRACT. Enzyme-linked immunosorbent assay (ELISA) was used to measure the antibody response to Pseudomonas aeruginosa exotoxin A, elastase, alkaline protease and phospholipase C in patients with cystic fibrosis (CF). Only the chronically colonized patients showed elevated antibody titres to phospholipase C (22/22 patients), alkaline protease (16/22 patients), exotoxin A (15/22 patients) and elastase (5/22 patients). In a few patients where serial specimens were available, rising titres were recorded to all four antigens during periods of active infection. Antibiotic treatment resulted in decrease of titres against all four antigens, but only the anti-exotoxin A and anti-elastase titres decreased to normal levels. Titres to phospholipase C were the least influenced by antibiotic treatment. The results imply different roles for these exoproteins in chronic colonization versus active infection. The levels of P. aeruginosa antibodies to exoproteins could probably be used in monitoring treatment of patients with CF.  相似文献   
39.
Flavanols--a class of plant polyphenols abundant in tea leaves and grape seeds and skins--have been found to inhibit some matrix-proteases instrumental in inflammation and cancer invasion, such as leukocyte elastase (LE) and gelatinases. In order to establish the relationship between chemical structure and activity, 27 different flavonoids (antocyanidins, dihydrochalcones, dihydroflavonols, flavanolignans, flavanols, flavones, flavonols and isoflavones) and other compounds with anti-oxidant properties were evaluated for their potential in blocking LE and gelatinase activities. LE activity was measured using a chromogenic substrate: from comparison of the different levels of inhibition, it was deduced that a crucial role in inhibition might be played by a galloyl moiety or hydroxyl group at C3, three hydroxyl groups at B ring, one hydroxyl group at C4', and a 2,3-double bond. Gelatinase activity was measured using the gelatin-zymography assay, and its inhibition showed that three hydroxyl groups at the A or B ring, or, for non-planar molecules, a galloyl moiety at C3 could be determinant. This comparative study is proposed as a basis for designing new molecules with enhanced anti-proteolytic activities, and no or reduced side-effects, for use in hindering inflammation, cancer invasion and angiogenesis.  相似文献   
40.
获得具有催化活性的人巨噬细胞弹性蛋白酶的催化区(hMECD),并建立有效的高通量筛选方法筛选其仰制剂.方法:在大肠杆菌中表达hMECD,并根据酶活性以比色法建立高通量筛选模型.对一批共8560个纯化合物和混合物进行了高通量筛选.结果:构建了有效的大肠杆菌表达系统.存在于包涵体中的表达蛋白在体外重折叠复性,经阴离子交 换柱层析的方法纯化,1L大肠杆菌培养物可得到23mg纯化的活性蛋白.该蛋白的重折叠复性和酶活性需要钙锌离子,但高浓度的锌离子则抑制其重折叠复性和活性.hMECD剪切合成底物包括一个硫酯和几个荧光发生的肽类底物,并在pH8.0显示最强的活性.对8560个化合物和混合物的高通量筛选发现了27个纯化合物和14个天然产物在20mg/L的浓度下具有大于80%的抑制活性.结论:建立了有效的人巨噬细胞弹性蛋白酶的催化区表达和纯化的方法.该重组蛋白抑制剂的高通量筛选模型具有有效、可信和快速的特点.  相似文献   
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