有机相中微生物脂肪酶合成短链脂肪酸酯的研究

用微生物脂肪酶在溶剂相中合成短链脂肪酸酯的研究表明：脂肪酶在正庚烷中催化合成短链脂肪酯转化率比水相中有明显的优势。在１０个不同来源的商品脂肪酶中，来自Ｍｕｃｏｒｍｉｅｈｅｉ，Ｃａｎｄｉｄａｒｕｇｏｓａ和Ｐｏｒｃｉｎｅｐａｎｃｒｅａｓ的脂肪酶合成酯转化率较高，其中Ｍｕｃｏｒｍｉｅｈｅｉ脂肪酶对己酸乙酯４８ｈ合成转化率达９４％，己酸乙酯产量３３．８４ｇ／Ｌ．同时就底物酸和醇的碳链长度对酯转化率的影响进行了研究。     

有机相脂肪酶催化合成技术在食品及相关领域的应用

对有机相脂肪酶催化合成技术的研究及其在食品、化妆品、医药、精细化工领域的应用进行了综述，表明有机相脂肪酶催化合成技术具有直接利用底物、反应条件温和、反应选择性高、产品容易分离纯化、产品具有绿色环保概念等优点。     

不同来源脂肪酶的催化反应性质比较

研究了三种脂肪酶的催化反应性质,包括水解作用pH、温度适宜范围,酶的酸碱稳定性和热稳定性,酶催化水解作用的底物脂肪酸特异性和酯键位置特异性,及对逆向反应的催化作用等。对三种酶的催化反应的机制进行了比较和讨论。     

非水相酶促酯交换法合成抗坏血酸脂肪酸酯

研究了一种L-抗坏血酸脂肪酸酯（AFAE）合成新途径。实验结果表明，氢化棕榈油、大豆油和海狗油等食用油脂作为脂肪酸基团供体，在固定化脂肪酶的催化下，在有机溶荆中与L-抗坏血酸直接进行酯交换反应形成L-抗坏血酸脂肪酸酯。对反应介质体系的筛选发现，在叔戊醇中用Novozym435催化此反应所得的产物浓度最高。对影响合成抗坏血酸脂肪酸酯的因素进行了探讨，确定了最适反应条件：初始油脂底物浓度为200-600mmol／L，温度为55℃，反应时间为9h。此条件下产物质量浓度可达43．51g／L。     

催化合成L-抗坏血酸棕榈酸酯的反应媒体和脂肪酶

对水、庚烷和叔戊醇等几种反应媒体和NOVO4 3 5(Candidaantartica) ,MML (Mucormiehei) ,LIPOLASE ,PPL(Porcinepancreas)等数种脂肪酶对L 抗坏血酸棕榈酸酯合成反应的影响进行了系统的研究 .结果表明 ,反应媒体及脂肪酶品种对反应影响极大 .所研究的几种反应媒体中 ,叔戊醇是唯一适用于该反应的反应媒体 .在所研究的几种脂肪酶中 ,NOVO 4 3 5表现出了良好的催化活性 ;MML也有一定活性 ,但不如NOVO 4 3 5,其相对活力只有NOVO 4 3 5的 2 0 % ,其余酶种则无催化活性 .     

血脂肪酶在急性重症胰腺炎早期诊断中的价值

目的:评价血脂肪酶在急性重症胰腺炎早期诊断中的价值.方法:采用酶显色法对61例急性重症胰腺炎,28例慢性胰腺炎及18例正常对照者进行血脂肪酶检测.结果:检出急性重症胰腺炎患者血脂肪酶(1 036.23±948.85) U/L,慢性胰腺炎患者血脂肪酶(276.54±543.18) U/L,正常对照组血脂肪酶(103.85±60.97) U/L,3组比较有统计学差异(P<0.0 001).急性重症胰腺炎、慢性胰腺炎和正常对照组血脂肪酶测量值不同,且重症胰腺炎患者测量值比慢性胰腺炎组及正常对照组测量值高.结论:血脂肪酶可以作为急性重症胰腺炎的诊断指标之一,具有一定的特异性.     

碱性脂肪酶的高效液相色谱和质谱分析

以常压层析系统纯化的碱性脂肪酶为出发蛋白,采用高效反相色谱对其进一步分离纯化,达到N末端氨基酸测序及肽谱分析所需的纯度.用电喷雾质谱测得脂肪酶的相对分子质量为27 217±1.对该脂肪酶的胰蛋白酶水解条件及肽段的相对分子质量等进行了研究.     

脂肪酶非水相转化失水山梨醇油酸酯

失水山梨醇单油酸酯（Ｓｐａｎ８０）可在非水相中用脂肪酶酶促转化合成．比较不同来源的脂肪酶和不同的非水相系统后发现：来源于假丝酵母的脂肪酶Ｎｏｖｏｚｙｍ４３５在无溶剂系统中有较高合成Ｓｐａｎ８０的能力．同时考察了水分对酯化反应的影响，并对酯化反应的条件如底物摩尔比、用酶量等进行了研究．与化学合成的产品比较，各项指标基本接近，但酶法合成的产品单酯含量较高，达８０％以上     

RNA干涉α-1,3-半乳糖转移酶对猪内皮细胞免疫和生理功能的影响

目的 通过RNA干涉沉默猪内皮细胞内α-1,3-半乳糖转移酶(α-1,3GT)基因,观察基因沉默对猪内皮细胞免疫和生理功能的影响.方法 提取原代猪主动脉内皮细胞,并通过SV40LT基因转染构建永生化猪主动脉内皮细胞系.用含猪α-1,3GT干涉基因的慢病毒载体转染细胞,并检测α-1,3GT和α-1,3-半乳糖抗原(α-1,3Gal)的表达情况.将转染后细胞与正常人血清共培养,建立异种移植免疫排斥反应的细胞模型并通过四甲基偶氮唑盐、流式细胞术、免疫组织化学及免疫荧光技术检测基因沉默对内皮细胞免疫和生理功能的影响.结果 永生化前后,细胞的免疫和生理功能无明显变化.RNA干涉后,永生化细胞表达α-1,3GT及α-1,3Gal明显减少.与人血清共培养后,转染组细胞增殖速度较高,凋亡率较低,与人免疫球蛋白IgM、IgG及人补体C3和C5b-9结合较对照组及错配组减少.结论 通过沉默α-1,3GT基因可降低猪内皮细胞与人免疫球蛋白、补体的结合程度.该基因沉默后的内皮细胞可作为异种移植急性排斥反应细胞模型和研究平台.     

无溶剂体系酶促合成甘油中碳酸偏酯

根据中碳酸转化率的大小 ,对 5种不同来源的固定化脂肪酶筛选 ,其中固定化脂肪酶SSW的酶催化转化率最高 ,辛酸和癸酸转化率分别为 91.5 %和 93.5 % ;对脂肪酶SSW酶促合成甘油辛酸偏酯的反应条件优化 ,适宜反应条件为 :敞口反应器中反应温度 5 5℃ ,每克酸加酶量 10 0U/g ,辛酸 /甘油投料摩尔比 1∶1.1,甘油初始加水量 4 % (质量分数 ) .实验范围内中碳酸品种对脂肪酶SSW不显示基质特异性 .     

Response Entropy is not more sensitive than State Entropy in distinguishing the use of esmolol instead of remifentanil in patients undergoing gynaecological laparoscopy

BACKGROUND: Monitoring of analgesia remains a challenge during general anaesthesia. Activation of Response Entropy (RE) to painful stimuli has been suggested to be a sign of inadequate analgesia. We evaluated the ability of RE to be more sensitive than State Entropy (SE) in measuring nociception in patients undergoing gynaecological laparoscopy. Our hypothesis was that while keeping SE at a predetermined level, RE would be higher in patients receiving a beta-blocking agent (esmolol) instead of an opioid (remifentanil) during a propofol/nitrous oxide anaesthesia. METHODS: Fifty-one women aged between 22-53 years were randomly assigned to receive esmolol (n=25) or remifentanil (n=26). SE was kept at 50+/-5. RE and SE were recorded at an interval of 30 s to 2 min and the areas under the RE and SE value-time curves (AUCRE and AUCSE) were calculated during the time of intubation and start of surgery as well as during the entire anaesthesia. The difference between RE and SE recordings in both groups was determined by subtracting the AUCSE from the corresponding AUCRE. Movements of the patients were recorded. RESULTS: No significant differences were detected in any of the several AUC values between the groups. The difference between RE and SE recordings was similar in both groups. Every patient in the esmolol group moved some time during the procedure interfering with surgery while no one in the remifentanil group moved. CONCLUSION: In patients undergoing gynaecological laparoscopic day-case surgery, RE seems not to be more sensitive than SE in guiding the use of opioids during general anaesthesia.     

Risk Factors of Reflux Esophagitis in the Cervical Remnant Following Esophagectomy with Gastric Tube Reconstruction

Background  The risk factors and suitable treatment of reflux esophagitis (RE) of the cervical remnant in patients undergoing radical esophagectomy remain unclear. The aim of this study was to evaluate the risk factors in patients with RE in the cervical remnant. Methods  We retrospectively examined 141 consecutive patients who underwent esophagectomy and reconstruction with gastric tubing. RE was diagnosed by upper gastrointestinal endoscopy and graded according to the Los Angeles Classification. Statistically, 11 potential risk factors of RE were evaluated. The postoperative follow-up time ranged from 18 to 204 months (median 60 months). Results  Among a total of 141 patients, 48 (34%) had RE in the cervical remnant, with 14 (29%) cases categorized as grade B, nine (19%) as grade C, and 25 (52%) as grade D. The cumulative incidence of RE in the cervical remnant was 24% at 5 years after surgery and 60% at 10 years, respectively. Pyloroplasty and bile reflux were identified as independent risk factors of RE in the cervical remnant by univariate and multivariate analyses. Conclusions  The results of this study show a high incidence and high grade of RE in the cervical remnant after esophagectomy. Routine endoscopic examination and suitable medication is required for the control of RE in the cervical remnant together with surgical procedures to avoid bile reflux.     

Psycho-biological correlates of rapid ejaculation in patients attending an andrologic unit for sexual dysfunctions

INTRODUCTION AND OBJECTIVES: Rapid ejaculation (RE) is the most common sexual dysfunction in males. The aim of the present study is to determine the contribution of intrapsychic, organic and relational factors to the pathogenesis of RE and the relationship between RE and erectile dysfunction (ED) in a sample of patients attending for the first time to an Outpatient Clinic for sexual dysfunction. METHODS: We studied a consecutive series of 755 patients using Structured Interview on Erectile Dysfunction (SIEDY), a brief, recently validated, multidimensional instrument specifically designed by our group for the study of pathogenetic factors of ED. RE was defined as ejaculation within 1 minute of vaginal intromission and its severity was categorized on a 4-point scale using a standard question. A complete physical examination and a series of biochemical, hormonal, psychometric, penile vascular and rigidometric evaluations were performed. RESULTS: Twenty-eight percent (n = 214) of patients attending to our sexology clinic reported RE of any degree. Patients reporting RE were younger (48.5 +/- 12.6 vs. 52.9 +/- 12.9 years old for RE and not RE respectively; p < 0.0001) and showed a higher prevalence of anxiety symptoms when compared to the rest of the sample. Among organic factors subjects with RE showed a higher prevalence of hyperthyroidism and significantly lower fasting plasma glucose (94 [87-110] and 98 [89-113] mg/dl for RE and non-RE respectively; p < 0.01). No difference among groups was observed for other hormones or clinical, biochemical and instrumental parameters. Finally RE patients showed a higher prevalence of partial erection sufficient for penetration when compared to the rest of the sample. Similar differences were observed between patients with and without RE when those without ED were excluded from the analysis. CONCLUSION: Our data suggest a minor involvement of organic factors to the pathogenesis of ED in patients with concomitant RE. On the other hand, in our sample, patients complaining about RE are younger, healthier than the rest of the sample and are characterized by high degree of anxiety symptoms and hyperthyroidism.     

Hepatic reticuloendothelial host defense failure following surgical trauma.

We evaluated potential pituitary-adrenal influences on postoperative reticuloendothelial (RE) function. Male dogs, 13 to 18 kg (28.6 to 39.6 lb), were used and the operative procedure was hemicolectomy. The RE function was evaluated by a colloid clearance technique and circulating opsonin levels were quantified by bioassay. Normal animals manifested RE depression three hours following incision (49 percent decline in the global phagocytic index K and an associated 30 percent decline in the circulating opsonic activity). Dexamethasone sodium phosphate pretreatment over a three-day preoperative period prevented the postoperative RE clearance failure (control K = 0.69; postoperative k = 0.79) however, a slight (18 percent) but not significant decrease in opsonic activity occurred. Cortisone acetate or adrenocorticotropic hormone over a wide-dosage range manifested no depressing effect on in vitro phagocytosis. These studies, in conjunction with our previous findings of Kupffer cell activation following adrenalectomy, as well as the demonstration of opsonin depletion and RE phagocytic depression following surgery in the absence of the adrenal glands suggest that the pituitary-adrenal system modulates postoperative RE phagocytosis.     

熵指数监测全麻患者镇静水平的准确性

目的 评价反应熵和状态熵监测全麻患者镇静水平的准确性.方法 择期行腹部手术患者20例,ASAⅠ或Ⅱ级,入室后监测反应熵(RE)、状态熵(SE)及脑电双频谱指数(BIS),静脉注射异丙酚、维库溴铵和芬太尼麻醉诱导,气管插管后机械通气,吸入七氟烷、间断静脉注射维库溴铵和芬太尼维持麻醉.分别于入室时、意识消失前10min、意识消失即刻、气管插管时、手术1 h、意识恢复前10 min、意识恢复即刻、拔管后10 min时记录RE、SE和BIS.结果 RE、SE和BIS在意识改变前后差异均有统计学意义(P＜0.05),RE、SE和BIS判断意识消失的临界值分别为76、73和68,灵敏度分别为94%、95%和92%,特异度分别为92%、94%和9l%,临界值判断意识消失的准确度分别为93%、95%、94%;判断意识恢复的临界值分别为82、75和70,灵敏度分别为95%、95%和91%,特异度分别为93%、96%和93%,临界值判断意识恢复的准确度分别为98%、96%和97%.结论 熵指数能够准确地监测全麻患者镇静水平.     

Spectral entropy and bispectral index as measures of the electroencephalographic effects of sevoflurane

BACKGROUND: Recently, entropy algorithms have been proposed as electroencephalographic measures of anesthetic drug effects. Datex-Ohmeda (Helsinki, Finland) introduced the Entropy Module, a new electroencephalographic monitor designed for measuring depth of anesthesia. The monitor calculates a state entropy (SE) computed over the frequency range of 0.8-32 Hz and a response entropy (RE) computed over the frequency range of 0.8-47 Hz. The authors investigated the dose-response relation of SE and RE during sevoflurane anesthesia in comparison with the Bispectral Index (BIS). METHODS: Sixteen patients were studied without surgical stimulus. Anesthesia was induced by sevoflurane inhalation with a tight-fitting facemask. Sevoflurane concentrations were increased and subsequently decreased and increased two to four times until the measurement was stopped and patients were intubated for surgery. The performances of SE, RE, and BIS to predict the estimated sevoflurane effect site concentration, obtained by simultaneous pharmacokinetic and pharmacodynamic modeling, were compared by calculating the correlation coefficients and the prediction probability. RESULTS: State entropy, RE, and BIS values decreased continuously over the observed concentration range of sevoflurane. Correlation coefficients were slightly but not significantly better for entropy parameters (0.87 +/- 0.09 and 0.86 +/- 0.10 for SE and RE, respectively) than for BIS (0.85 +/- 0.12). Calculating the prediction probability confirmed these results with a prediction probability of 0.84 +/- 0.05 and 0.82 +/- 0.06 for SE and RE, respectively, and 0.80 +/- 0.06 for BIS. CONCLUSION: State entropy and RE seem to be useful electroencephalographic measures of sevoflurane drug effect.     

Comparative effects of ketamine on Bispectral Index and spectral entropy of the electroencephalogram under sevoflurane anaesthesia

Background. The Bispectral Index (BIS) and spectral entropyof the electroencephalogram can be used to assess the depthof hypnosis. Ketamine is known to increase BIS in anaesthetizedpatients and may confound that index as a guide to steer administrationof hypnotics. We compared the effects of ketamine on BIS, responseentropy (RE) and state entropy (SE) during surgery under sevofluraneanaesthesia. Methods. Twenty-two women undergoing gynaecological surgerywere enrolled in this double-blind, randomized study. Anaesthesiawas induced i.v. and maintained with sevoflurane. Under stablesurgical and anaesthetic conditions, patients were assignedto receive either a bolus of ketamine 0.5 mg kg^–1 or thesame volume of saline. Blood pressure, heart rate, BIS, RE andSE were measured every 2.5 min from 10 min before (baseline)until 15 min after ketamine or saline administration. The maximumrelative increase in BIS, RE and SE compared with baseline wascalculated for each patient. Values are mean (SD). Results. Baseline values were BIS 33 (4), RE 31 (5), SE 30 (5)for the ketamine patients and BIS 35 (3), RE 33 (5) and SE 32(6) for the patients receiving saline. BIS, RE and SE increasedsignificantly from 5 min (BIS) and 2.5 min (RE and SE) afterketamine administration, peaking at 46 (8) (BIS), 52 (12) (RE)and 50 (12) (SE) respectively. The maximum relative increasein RE [42.2 (10.4%)] and SE [41.6 (10.9)%] was higher than thatof BIS [29.4 (10.4%)]. Blood pressure, heart rate and RE–SEgradient did not change in either group. Conclusions. Ketamine administered under sevoflurane anaesthesiacauses a significant increase in BIS, RE and SE without modificationof the RE–SE gradient. This increase is paradoxical inthat it is associated with a deepening level of hypnosis.     

Monocyte procoagulant activity and plasminogen activator. Role in human renal allograft rejection

Currently the mechanism of renal allograft rejection is not well understood. This study was designed to determine whether induction of monocyte procoagulant activity (MCPA) is important in the pathogenesis of renal allograft rejection. The MPCA assay was performed utilizing a one stage clotting assay both in normal and in factor-VII-deficient plasma. There was no increase in spontaneous MPCA in 20 patients with endstage renal failure and in 10 patients following abdominal or orthopedic operation, as compared with 20 normal controls. MPCA was assessed daily in 18 patients who had received renal allografts. Rejection episodes (RE) were predicted on the basis of persistent elevation in MPCA as compared with pretransplant levels. Rejection was diagnosed clinically and treated on the basis of standard criteria. Treated RE were compared with those predicted by elevated MPCA, and 3 patients were assessed as having no RE by MPCA and by standard criteria. In 8 RE, MPCA correlated temporally with RE (same day) when compared with standard criteria. In 12 RE, MPCA was predictive of rejection preceding standard criteria by at least 24 hr. There were 7 false-positive predictions on the basis of MPCA; however, there was only 1 false negative. MPCA was shown to be a prothrombinase by its dependence only on prothrombin and fibrinogen for full activity. MPCA may be important in the pathogenesis of allograft rejection, and additionally it may be a useful adjunct in the clinical management of this disease.     

Spectral entropy and bispectral index as measures of the electroencephalographic effects of propofol

Recently, Datex-Ohmeda introduced the Entropy Moduletrade mark for measuring depth of anesthesia. Based on the Shannon entropy of the electroencephalogram, state entropy (SE) and response entropy (RE) are computed. We investigated the dose-response relationship of SE and RE during propofol anesthesia in comparison with the Bispectral Indextrade mark (BIS). Twenty patients were studied without surgical stimulus. Anesthesia was induced by a constant propofol infusion of 2000 mg/h (451 +/- 77 microg x min(-1) x kg(-1)) via a large forearm vein. Propofol was infused until substantial burst suppression occurred (more than 50%) or mean arterial blood pressure decreased to <60 mm Hg. Hereafter, infusions were stopped until recovery of BIS values up to 60 was reached. Subsequently, the constant propofol infusion of 2000 mg/h was restarted to increase depth of anesthesia and again decreased (infusion was stopped) within the BIS value range of 40-60. The coefficient of determination (R2) and the prediction probability (P(K)) were calculated to evaluate the performance of SE, RE, and BIS to predict changing propofol effect-site concentrations. R2 values for SE, RE, and BIS of 0.88 +/- 0.08, 0.89 +/- 0.07, and 0.92 +/- 0.06, respectively, were similar. The calculated P(K) values, however, revealed a significant difference between SE and RE compared with BIS, with P(K) = 0.77 +/- 0.09, 0.76 +/- 0.10, and 0.84 +/- 0.06, respectively. BIS seems to show slight advantages in predicting propofol effect-site concentrations compared with SE and RE, as measured by P(K) but not as measured by R2.     

Communication between organ donor families and recipients: a definitely controversial subject

In transplant centers, few topics are more controversial than communication between organ donor families (ODF) and recipients (RE). The Organ Procurement Organizations and transplant centers have felt obliged to protect the confidentiality and interests of ODF and RE. However, some authors have reported favorable effects of contact between ODF and RE. This study sought to investigate the current situation of the communication between ODF and RE from the viewpoint of transplanted patients (n = 50) and waiting transplant patients (n = 50) at a Brazilian University Hospital, ODF (n = 10), physicians from transplant centers (n = 50), as well as the opinion of the general population of a Brazilian city (n = 100). This work was developed as a survey whose questions related to the issue of communication between ODF and RE. The results showed that the majority of transplanted patients (82%) and patients awaiting transplant (60%) wanted to meet ODF to express their gratitude for receiving the organ. Likewise, ODF (67%) wanted to have a meeting with recipients, which allowed them to confirm the benefit of their donation. The general population was also favorable (66%) to ODF and RE communication. In contrast, the physicians (74%) were opposed to the ODF and RE contact. They affirmed that direct contact could lead to serious emotional conflicts or attempts of material involvement. One believes that decisions concerning the contact between ODF and RE would have to be determined by the involved parties. The transplant team could analyze the requests case by case, but ODF and RE must have the right to make the final decision.