A quantitative enzyme-linked immunosorbent assay for quantification of secretory immunoglobulin A in serum.

Secretory immunoglobulin A (SIgA) in serum is possibly the best index of SIgA presence in mucosal secretions in digestive tract and the mirror of its immunologic barrier against many pathogenic aggressions. The measurement of salivary SigA alone may be affected by total salivary secretion and its final concentration in the gland lumen is probably not useful as an appropriate index of mucosal secretions in the digestive tract. The usefulness of the determination of SigA against various epitopes in serum from patients with various autoimmune disease has been demonstrated. The aetiology of many digestive related disorders could be triggered by an alteration of mucose SIgA barrier. The determination of Igs is important for different liver diseases and specifically the SIgA in autoimmune diseases such as rheumatoid arthritis. We developed an easy and efficient immunologic assay to quantify SIgA in serum samples.

Association between anti-Anisakis simplex antibodies and interleukin-7 levels.

IL-7 is a crucial factor for the development of lymphocytes, and it is absolutely necessary for γδ T cells. Mice deficient in L-7 have a deficit of B and αß T lymphocytes, and an absence of mature γδ TCR cells. IL-7 is essential for the survival, development and maturation of Schistosoma sp., although its production is associated with protection against intestinal helminths. The presence of anti-Anisakis simplex antibodies, especially IgA, is related to a lower frequency in CD3 + CD56 + αß + lymphocytes and all subpopulations of γδ T cells. In this work, the relationship of IL-7 with humoral and cellular responses against A. simplex in 100 healthy subjects was studied. We have found significantly higher IL-7 levels in anti-A. simplex IgA-positive subjects (p < 0.001). The positivity of anti-A. simplex IgA was associated with a significant reduction in the frequency of CD3 + αß+ (p < 0.01), CD3 + CD4 + αß+, CD3 + CD8 + αß+, CD3 + CD56 + αß+, CD3 + Î³Î´+, CD3 + CD4-CD8-γδ+ and CD3 + CD56 + Î³Î´+ (p < 0.05) cells. In the case of NKT cells, this same phenomenon was also associated with IgE positivity. There was a weak inverse correlation (Spearman) of IL-7 levels with the frequencies of CD3 + CD4 + αß+ (-0.125, p = 0.047), CD3 + CD8 + αß+ (-0.204, p = 0.032), CD3 + CD56 + αß+ (-0.247, p = 0.007), CD3 + Î³Î´+ (-0.267, p = 0.007), CD3 + CD4-CD8-γδ+ (-0.266, p = 0.003), and CD3 + CD8 + Î³Î´ + (-0.302, p = 0.002) cells. The role of NKT cells in the anti-A. simplex response was confirmed and an association between IL and 7 levels and specific antibodies, especially IgA, was demonstrated. The higher production of IL-7 would represent a compensatory mechanism in response to the reduction in lymphocyte populations associated with the response against this parasite.

Myocardial oxidative stress protection by sevoflurane vs. propofol: a randomised controlled study in patients undergoing off-pump coronary artery bypass graft surgery.

CONTEXT: Myocardial oxidative stress plays an essential role in the pathogenesis of ischaemia-reperfusion injury associated with coronary artery bypass grafting (CABG). Both propofol and volatile anaesthetics have been shown to reduce reactive oxygen species in experimental and clinical studies. MAIN OBJECTIVE: To compare the influence of sevoflurane and propofol on myocardial oxidative stress markers (F2-isoprostanes and nitrates/nitrites) in coronary sinus blood samples from patients undergoing off-pump CABG. DESIGN AND SETTING: Randomised controlled clinical study of patients scheduled for off-pump CABG in a tertiary academic university hospital from June 2007 to August 2009. Forty patients consented to enrolment and were assigned to receive either propofol or sevoflurane. INTERVENTIONS: Upon completion of the proximal anastomosis, a retroplegia cannula was inserted in the coronary sinus to obtain blood samples, according to the study protocol. MAIN OUTCOME MEASURES: Markers of lipoperoxidation (F2-isoprostanes) and nitrosative stress (nitrates/nitrites) were measured in coronary sinus blood samples at three time points: after the end of the proximal anastomosis (T1), after completion of all grafts (T2) and 15 min after revascularisation (T3). RESULTS: Of the 40 recruited patients, 38 fully completed the study. In the sevoflurane group (n = 20), concentrations of oxidative stress markers in the coronary sinus remained almost constant and were significantly lower than those in the propofol group (n = 18) at all time points. F2-isoprostanes concentrations were as follows at T1: sevoflurane group 37.2 ±â€Š27.5 pg ml vs. propofol group 170.7 ±â€Š30.9 pg ml [95% confidence interval (CI) 112.16-155.08, P < 0.0001); at T2: sevoflurane group 31.94 ±â€Š24.6 pg ml vs. propofol group 171.6 ±â€Š29.7 pg ml (95% CI 119.78-159.63, P < 0.0001); and at T3: sevoflurane group 23.8 ±â€Š13.0 pg ml vs. propofol group 43.6 ±â€Š31 pg ml (95% CI 2.87-36.63, P = 0.023). CONCLUSION: In patients undergoing off-pump CABG, sevoflurane showed better antioxidative properties than propofol.

Considerations on pancreatic exocrine function after pancreaticoduodenectomy.

The pancreaticoduodenectomy (PD) procedure may lead to pancreatic exocrine and endocrine insufficiency. There are several types of reconstruction for this kind of operation. Pancreaticogastrostomy (PG) was introduced to reduce the rate of postoperative pancreatic fistula. Although some randomized control trials have shown no differences regarding pancreatic leakage between PG and pancreaticojejunostomy (PJ), recently some reports reveal benefits from the PG over the PJ. Some surgeons concern about the performing of the PG and inactivation of pancreatic enzymes being in contact with the gastric juice, and the detrimental results over the exocrine pancreatic function. The pancreatic exocrine function can be measured with direct and indirect tests. Direct tests have the highest sensitivity and specificity for detection of exocrine insufficiency but require tube placement. Among the tubeless indirect tests, the van de Kamer stool fat analysis remains the standard to diagnose fat malabsorption. The patient compliance and time consuming makes it not so suitable for its clinical use. Fecal immunoreactive elastase test is employed for screening of exocrine insufficiency, is not cumbersome, and has been used to study pancreatic function after resection. We analyze the FE1 levels in our patients after the PD with two types of reconstruction, PG and PJ, and we discuss some considerations about the pancreaticointestinal drainage method after pancreaticoduodenectomy.

Deficit of interleukin 7 in septic patients.

We recently demonstrated an overall decrease of all αß and specially γδ T cell subsets in patients with sepsis compared with healthy subjects. IL-7 is a crucial factor for development of γδ T cells and survival in sepsis but its association with sepsis severity, evolution of organ failure and death still has not been investigated. Sera from 78 patients who met criteria for sepsis were analyzed vs control group. Septic patients showed the lowest levels of IL-7. Patients with severe sepsis reached levels of IL-7 higher than those observed in the groups of uncomplicated sepsis and septic shock. The frequency of γδ T cells at admission was lower in septic patients vs control group. At the time of admission, the frequency of γδ T cells in septic patients who subsequently died was lower than the observed in the group of patients that instead survived.

Oxidative stress injury after on-pump cardiac surgery: effects of aortic cross clamp time and type of surgery.

BACKGROUND: Cardiopulmonary bypass (CPB) in on-pump cardiac surgery can have harmful systemic effects, triggered in part by radical oxygen species (ROS) produced by ischemia-reperfusion in the heart and the lung. We determined the relationship between levels of oxidative stress markers (8-isoprostane and nitrites/nitrates) in plasma with aortic cross clamp duration in patients undergoing cardiac surgery with CPB. METHODS: Thirty patients with CPB were studied: 14 with coronary artery bypass graft surgery and 16 with valve surgery. Plasma levels of 8-isoprostane, and nitrites/nitrates were measured over a 24-hour time course: before (T0) and after CPB: 5 minutes (T1), 1 hour (T2), 12 hours (T3), and 24 hours (T4). RESULTS: Plasma levels of 8-isoprostane and nitrites/nitrates increased early after CPB, with a subsequent and progressive decline. Levels of oxidative stress markers in T1-T2 were positively correlated with the aortic cross clamp duration. Aortic cross clamp duration times greater than 50 minutes were correlated with higher oxidative stress levels. There were no significant differences in the levels of oxidative stress markers between surgery types. CONCLUSION: Cardiac surgery with CPB is associated with an early increase of oxidative stress markers in systemic blood. Aortic cross clamp duration is positively correlated with oxidative stress injury.

Surgical versus nonsurgical treatment of infected pancreatic necrosis: more arguments to change the paradigm.

OBJECTIVES: This study aimed to compare primary surgical versus nonsurgical treatment in a series of patients with infected pancreatic necrosis (IPN) and to investigate whether the success of nonsurgical approach is related to a less severe disease. METHODS: Thirty-nine consecutive patients with IPN have been included and further subdivided into two groups: primary surgical (n = 21) versus nonsurgical (n = 18). Outcome measures were the differences in mortality, morbidity, and pancreatic function. Comorbidity, organ failure, and other severity indexes were compared between the two groups. RESULTS: Mortality occurred in 16.7% of cases in the nonsurgical group versus 42.9% in the surgical group. In the primary nonsurgical group, seven were operated on due to failure of initial conservative treatment. In this latter group, mortality was 28.6% and was performed significantly later than in the primary surgical group. The group of primary surgical treatment was associated with a significant higher rate of multiple organ failure (MOF) at IPN diagnosis, new onset or worsening of organ failure, and MOF and nosocomial infection after surgery. CONCLUSIONS: Initial nonsurgical approach in IPN is associated with better results both in cases which respond to this treatment as well as in those who, failing this conservative approach, have to be operated on after a delayed period. Primary surgically treated patients had a more severe disease at the time of IPN.

Different oxidative stress marker levels in blood from the operated knee or the antecubital vein in patients undergoing knee surgery: a tourniquet-induced ischemia-reperfusion model.

BACKGROUND: In knee surgery a tourniquet is usually applied in order to provide a bloodless surgical field. This study aims to compare, in a tourniquet-induced ischemia-reperfusion model, the glutathione oxidation and lipid peroxidation in two different blood sources: an operated knee drainage tube or the antecubital vein. METHODS: Thirty-two patients undergoing total knee replacement were studied. We measured reduced glutathione (GSH), oxidized glutathione (GSSG), malondialdehyde (MDA) and other metabolic parameters in the blood from the operated knee (17 patients), or from the antecubital vein (15 patients) before tourniquet inflation (T(0)) and after tourniquet release at different times: 3, 10, and 60 minutes (T(1), T(2), and T(3), respectively). RESULTS: We have found an early increase of approximately 100% in GSSG and MDA blood levels coinciding with a decrease in GSH levels at T(1)-T(3) in blood from the operated knee. These changes were also observed in blood from the antecubital vein at T(1) and T(2), but at lower levels than in blood from the operated knee. CONCLUSIONS: There is an intense glutathione oxidation and lipid peroxidation in the operated knee after tourniquet deflation. The surgical drainage is a good source of blood for the determination of biomarkers in a tourniquet-induced ischemia-reperfusion model, because changes are observed more early and it is more direct than another source of systemic blood.

Hyperoxia during colon surgery is associated with a reduction of xanthine oxidase activity and oxidative stress in colonic mucosa.

BACKGROUND: Gut manipulation during surgery may induce local oxidative stress. Supplemental inspired oxygen increases arterial and tissue oxygen partial pressures. This study examined whether a 0.80 fraction of inspired oxygen (FiO(2)) attenuates the oxidative stress, reducing xanthine oxidase (XO) activity in colonic mucosa as a possible mechanism during colon surgery. METHODS: Twenty-four cancer patients who underwent elective colon resection were randomly assigned to either 0.30 FiO(2) or 0.80 FiO(2) during surgery. Malondialdehyde (MDA) and oxidized glutathione (GSSG) levels were measured in blood plasma. We also determined the enzymatic activities of XO and xanthine dehydrogenase (XDH) in the colonic mucosa after resection of the piece of colon. RESULTS: Oxygen partial pressure in arterial blood was higher in the 0.80 FiO(2) group than in the 0.30 FiO(2) group (P<0.001). MDA and GSSG levels measured in blood plasma as well as MDA measured in colonic mucosa were lower in the 0.80 FiO(2) group than in the 0.30 FiO(2) group. Otherwise, XO enzymatic activity and XO/(XO+XDH) ratio in colonic mucosa were lower in the 0.80 FiO(2) group than in the 0.30 FiO(2) group. CONCLUSIONS: XO may be a major source of reactive oxygen species in patients during colon surgery. Inspiring 0.80 oxygen during colon surgery increases arterial partial pressure and this treatment was associated with reduced XO activity and levels of oxidative stress in colonic mucosa.

Bemiparin improves the total antioxidant status in plasma.

The aim of this work is to test the protective effect of bemiparin (3500 I.U., s.c.) against oxidative stress in plasma from healthy volunteers. We have evaluated the total antioxidant activity in plasma, superoxide dismutase and glutathione peroxidase activities, and oxidized glutathione and malondialdehyde levels, in two groups: treated (n=20) and control (n=15). Blood samples were collected at: basal, 2, 4, 6, 8 and 10 h. Total antioxidant activity and antioxidant enzymes activity were higher in the treated group at 2-6 h. However, oxidized glutathione and malondialdehyde levels were lower in the treated group at same times. The results suggest that bemiparin exerts an early beneficial effect against oxidative stress in plasma.

Secretory immunoglobulin A (sIgA) deficiency in serum of patients with GALTectomy (appendectomy and tonsillectomy).

INTRODUCTION: In adult human beings, 80-85% of the immune cells are located in the digestive tract mucosa; hence the importance of the Gut Associated Lymphoid Tissue (GALT) in host defence. We studied the influence of the surgical removal of two important parts of the gut associated with lymphoid tissue (tonsillectomy and appendectomy) on immune parameters. METHODS: One hundred and sixty patients were enrolled in this study. They were divided into four groups of forty patients each and matched for gender and age: group 1, appendectomized and tonsillectomized; group 2, only appendectomized; group 3, only tonsillectomized; and group 4, control group, neither tonsillectomized nor appendectomized. We analysed in blood: hemogram, protein electrophoresis, lymphocytic populations (T4 cells, T8 cells, NK cells), IgG, IgM, IgA immunoglobulin, and their fractions IgA1, IgA2, and secretory IgA. RESULTS: Levels of secretory IgA in serum of patients in group 1 were significantly lower than in the other three groups (1.89 mg/dl, group 1; 2.32 mg/dl, group 2; 2.19 mg/dl, group 3 and 4.97 mg/dl, group 4; p<0.0001). Also, the values found in the two groups that had undergone only one of the operations were clearly lower than in control patients (p<0.0001). In this study, the reduction was sustained for a period of between 3 months and 3 years in appendectomized patients, and more than 20 years in tonsillectomized patients. IN SUMMARY: GALTectomy (appendectomy and tonsillectomy) significantly decreases secretory IgA levels in serum. The decrease is more intense when both operations have been done.