微生物产生的淀粉酶抑制制研究Ⅱ．发酵、分离与理化性质

Ｓ－２－３５菌株产生的淀粉酶抑制剂对人体内的ａ－淀粉酶、唾液酸酶有明显的抑制作用。该产生菌在２８℃摇瓶发酵时，碳源利用率高于氮源利用率。发酵４８小时后，菌丝的生长速度随着碳源利用率的加速而加快。淀粉酶抑制剂的含量在２５小时后迅速提高，并在７２小时达最高峰。发酵液经活性炭吸附，ＤＥＡＥ－５２纤维索、ＣＭ－３２纤维素和ＳｅｐｈａｄｅｘＧ－２５层析后的活性部分经ＨＰＬＣ得三个活力峰。显色反应表明对茚三酮、双缩脉呈阴性反应，对吐伦、间苯二酚、Ａｎｔ－ｈｒｏｎｅ和ＫＭｎＯ＿４呈阳性反应。紫外光谱呈末端吸收，红外光谱在３３９１、１４１０、１０３０及９２７ｃｍ￣（－１）处有吸收峰。质谱测定Ａ组分分子量为９４４。     

血清脂肪酶,淀粉酶比在区分轻重型急性胰腺炎中的作用

检测３０例急性胰腺炎患者入院１周内脂肪酶和淀粉酶活性的比率。直接应用Ｌ／Ａ比率的数值区分两型急性胰腺炎，结果表明，１周内两型之间的Ｌ／Ａ比率无显著差异性。但将此定量资料转化为定性资料后，则可以区分出两型急性胰腺炎：取３０例患者入院第三天Ｌ／Ａ均值作为常数Ｃ，再分别应用入院第一天的Ｌ／Ａ减去Ｃ得差值，ａ，若ａ〉０则为坏死型胰腺炎，ａ≥０则为水肿型胰腺炎，结果发现，轻重型之间有差异，Ｐ〈０．０５。     

Immunoreactive trypsin in the adult respiratory distress syndrome

With the purpose of studying the role of proteinases in the development of ARDS, plasma levels of immunoreactive trypsin (IRT) and amylase were measured in 43 intensive care patients at risk of developing ARDS (22 polytrauma, seven abdominal surgery, four burns, two DIC and eight pancreatitis). Twenty four of these 43 patients developed ARDS and 31 presented abnormal IRT values (above 70 g/L). Twenty-one of these 31 patients had ARDS; a significant correlation thus appeared between ARDS and abnormal IRT values. In nine patients, IRT values were higher than 800 g/L and remained high for 3 to 4 days. A statistically significant correlation also appeared between abnormal IRT and septic phenomena: 20 patients with high IRT values presented septic problems. When IRT values were high, amylase values were often also abnormal: 12 of 23 patients with high IRT had abnormal amylase levels (the eight patients with documented pancreatitis were excluded); no other clinical signs or symptoms of pancreatitis were present in these patients. IRT could be one of the mediators of ARDS in septic patients. It is not clear that the pancreas is the origin of IRT in all cases.     

乌司他丁联合奥曲肽治疗急性胰腺炎的疗效及对细胞因子和淀粉酶的影响

目的：探讨乌司他丁联合奥曲肽治疗急性胰腺炎的临床疗效以及对细胞因子和淀粉酶的影响。方法：选取在本院接受治疗的急性胰腺炎患者168例,将其随机分为乌司他丁组、奥曲肽组和联合治疗组3组,每组各56例。3组均进行常规治疗,在此基础上,乌司他丁组给予乌司他丁静脉滴注,奥曲肽组给予奥曲肽静脉泵注,联合用药组给予两种制剂的联合应用。观察3组临床治疗效果以及治疗前后细胞因子和淀粉酶的变化情况。结果：联合治疗组总有效率明显高于乌司他丁组和奥曲肽组,差异具有统计学意义（P〈0.05）。3组治疗后细胞因子和淀粉酶水平都有一定程度的改善,而乌司他丁组和奥曲肽组对细胞因子和淀粉酶变化的影响是一致的,差异无统计学意义（P〉0.05）;而联合治疗组细胞因子和淀粉酶水平变化明显优于单独用药组,且差异均具有统计学意义（P〈0.05）。结论：乌司他丁和奥曲肽联合应用治疗急性胰腺炎在改善患者临床症状和体征、降低细胞因子和淀粉酶等方面都要明显优于两种药物单独使用,具有更好的治疗效果,值得临床大力推广和应用。     

The Physiology of the Transplanted Small Bowel: An Overview with Insight into Graft Function

Nilsson J, Sjödin L, Gylfe E. Supramaximal inhibition of cholecystokinin-induced pancreatic amylase release involves desensitization to cytoplasmic Ca²⁺. Scand J Gastroenterol 1994;29:561-568.

Background: Cholecystokinin (CCK) is a major stimulant of pancreatic enzyme secretion. The dose-response relationship for CCK-induced secretion is bell-shaped, with a characteristic supramaximal inhibition. The mechanism for this inhibition has now been studied.

Methods: The kinetics of amylase release and the changes of the cytoplasmic Ca²⁺ concentration ([Ca²⁺]i) were recorded during stimulation of guinea-pig pancreatic acinar cells with different concentrations of cholecystokinin octapeptide (CCK-8) and the Ca²⁺ ionophore ionomycin. Results: Individual cells reacted with [Ca²⁺]_i oscillations at 10^?11 10^?10 M CCK-8 and with an initial peak followed by a sustained suprabasal level at 10 ^?9–10^?8 M of the agonist. The latter response was also seen in suspensions of acinar cells at all tested concentrations of CCK-8 and at 10^?6-10^?5 M of ionomycin. With increases of extracellular Ca²⁺ from 0.5 to 5.0 mM there was a rise of [Ca²⁺]_i during exposure to 10^?9-10^?8 M CCK-8 or 10^?5 M ionomycin but a paradoxical decrease at lower concentrations of CCK-8 or ionomycin. A dose-dependent increase of amylase release was seen at CCK-8 concentrations from 10^?11 to 10^?9M. At 10^?9-10^?8M CCK-8 secretion was characterized by an initial peak followed by a sustained phase. Whereas the initial peak of secretion remained unaffected by increasing CCK-8 from 10^?9 to 10^?8M, the sustained phase was inhibited (supramaximal inhibition). Increasing extracellular Ca²⁺ from 0.5 to 5.0 mM transiently enhanced secretion in response to 10^?9 M but lacked effect during supramaximal inhibition of secretion by 10^?8 M CCK-8.

Conclusions: Both initial and sustained CCK-8-stimulated amylase release increase with [Ca²⁺]_i. However, supramaximal inhibition of secretion was not due to a decrease of [Ca²⁺]_i but was characterized by desensitization to the stimulatory effect of [Ca²⁺]_i.     

Allergy to flour and fungal amylase in bakery workers

The purpose of this study was to describe the prevalence ofrespiratory symptoms and skin prick test findings in a groupof 383 employees in a plant bakery population who had the greatestregular exposure to ingredient dusts. The prevalence of positiveskin prick tests to fungal amylase was 16%, in contrast to 6%to wheat flour, suggesting that the principal sensitiser isfungal amylase and not flour. Furthermore, the findings suggestthat symptomatic allergy to bread-baking ingredients is uncommon(3.1%). In comparison, occasional short-lived symptoms whichdo not appear to have an allergic aetiology are relatively prevalent(17.2%). Where sensitisation to ingredients arises, fungal amylasepresent in bread improvers is the principal allergen.     

微生物产生的淀粉酶抑制剂研究Ⅲ淀粉酶抑制剂抑制动力学研究

Ｓ－２－３５淀粉酶抑制剂是一种易溶于水、不溶于有机溶剂的白色粉末，其紫外谱图呈末端吸收，红外谱图在３３９１、１５７２、１４１０、１０３０及９２７ｃｍ￣（－１）处有明显吸收峰。该抑制剂在ｐＨ６．５的条件下对ａ－淀粉酶有明显的抑制作用（ＩＤ＿（５０）为１．７×１０－５ｍｏｌ／Ｌ）．在３７℃，ｐＨ６．５的磷酸缓冲液中，Ｓ－２－３５抑制剂对淀粉酶的抑制作用与抑制剂的浓度关系密切，在抑制剂浓度较小的情况下，抑制剂与酶的结合呈直线关系，随着抑制剂浓度增大，残留活力曲线则出现漂移。根据Ｄｉｘｏｎ图和Ｌｉｎｅｗｅａｖｅｒ－Ｂｕｒｋ图的研究表明，Ｓ－２－３５淀粉酶抑制剂对淀粉酶的结合和底物呈竞争性抑制，抑制常数Ｋ＿ｉ为１．５～１．６×１０￣（－６）ｍｏｌ／Ｌ。     

Respiratory symptoms and sensitization in bread and cake bakers

This purpose of this study was to examine the relationship betweenexposure to wheat flour, soya flour and fungal amylase and thedevelopment of work-related symptoms and sensitization in breadand cake bakery employees who have regular exposure to thesesubstances. The study populations consisted of 394 bread bakeryworkers and 77 cake bakery workers whose normal jobs involvedthe sieving, weighing and mixing of ingredients. The groupswere interviewed with the aim of identifying the prevalence,nature and pattern of any work-related respiratory symptoms.They were also skin-prick tested against the common bakery sensitizingagents, i.e., wheat flour, soya flour, rice flour and fungalamylase. The results of personal sampling for sieving, weighingand mixing operations at the bakeries from which the study groupswere taken were collated in order to determine typical exposuresto total inhalable dust from the ingredients, expressed as 8hour time-weighted average exposures. Data from the health surveillanceand collated dust measurements were compared with the aim ofestablishing an exposure-response relationship for sensitization.The prevalence of work-related symptoms in bread bakery andcake bakery ingredient handlers was 20.4% and 10.4% respectively.However, in a large proportion of those reporting symptoms inconnection with work, the symptoms were intermittent and ofshort duration. It is considered that the aetiology of suchsymptoms is likely to be due to a non-specific irritant effectof high total dust levels, rather than allergy. None of thecake bakers and only 3.1% of the bread bakers had symptoms whichwere thought to be due to allergy to baking ingredients. Usingskin-prick testing as a marker of sensitization, the prevalenceof positive tests to wheat flour was 6% for the bread bakersand 3% for the cake bakers. Comparable prevalences for soyaflour were 7% and 1 % respectively. However, the prevalenceof positive skin-prick tests to fungal amylase was 16% amongstthe bread baking group with only a single employee (1 %) inthe cake baking group having a positive test. Furthermore, thisemployee had previously worked in a bread bakery. The differencein rates of sensitization to wheat flour between the bread andcake bakers is not statistically significant, whereas the differencefor soya flour is at the borderline of statistical significance(p=0.045). In contrast, the difference in fungal amylase sensitizationis significant at the 0.1% level. For both bread and cake bakers,the 8 hour time-weighted average exposures for each of the activitiesshowed a wide variation with mixing having the lowest averageexposure and sieving the highest. Out of the allergens studiedin this investigation, fungal amylase is the principal sensitizerin large scale bread bakeries, with the main source of exposurebeing the handling of bread improvers. In contrast, the riskof sensitization to wheat flour is low in both bread and cakebakeries. The absence of positive skin-prick tests in the subgroupof cake bakery employees who regularly handle fungal-amylase-containingflour suggests that their levels of exposure are below the thresholdfor sensitization to amylase.