P A Bonini’s research while affiliated with Istituto di Ricovero e Cura a Carattere Scientifico San Raffaele Pisana and other places

To determine whether preoperative left ventricular ejection fraction (LVEF) is related to the degree of myocardial oxidative stress during bypass surgery in man. Observational study. Tertiary care centre. 31 patients (LVEF range was 20% to 68%) undergoing elective coronary bypass surgery with blood cardioplegic reperfusion were studied. Arterial and coronary sinus blood was collected before aortic cross clamping (T0) and at 0 (T1), 15 (T2), and 30 (T3) minutes after unclamping. Transmural left ventricular biopsies were also obtained from 15 patients at T0 and at T1. Glutathione and adenine nucleotides were measured in myocardial biopsies, while coronary sinus-artery differences for glutathione, nucleotides, and products of lipid peroxidation were calculated from blood specimens. Creatine kinase (myocardial band; CK-MB) was measured in plasma at four and 12 hours after operation. Myocardial glutathione and adenine nucleotides were correlated (p < 0.02) with preoperative LVEF both at T0 (r = 0.909 and 0.672) and T1 (r = 0.603 and 0.605). Oxidised glutathione released from the heart during reperfusion was inversely correlated with LVEF (r = -0.448, -0.466, and -0461 at T1, T2, and T3, p < 0.01), while reduced glutathione (r = 0.519 and 0.640 at T1 and T2) and glutathione redox ratio (r = 0.647, 0.714, 0.645, and 0.702 at T0, T1, T2, and T3) showed a direct correlation (p < 0.01). Lipid peroxidation at T1 was negatively related to LVEF (r = -0.492). CK-MB was also negatively related to LVEF (r = -0.440 at 4 h and -0.462 at 12 h). The capacity to counterbalance oxidative burst following ischaemia and reperfusion appears to be related to the functional ability of the heart.

To evaluate the role of leucocytes in free radical production in patients with depressed or normal ejection fraction undergoing coronary bypass. Two randomised control trials. Tertiary care centre. In the first study, 22 patients with ejection fractions of < or = 40% received blood cardioplegic reperfusion with (n = 11) or without (n = 11) leucocyte depletion. In the second study, 22 patients with ejection fractions > or = 45% received either leucocyte depleted (n = 11) or blood cardioplegia (n = 11). Glutathione, hypoxanthine, and lipid peroxidation products were measured in coronary sinus blood and plasma before aortic cross clamping and at 0, 15, and 30 minutes after unclamping. Haemodynamic variables and creatine kinase MB isoenzymes were monitored on the first postoperative day. Comparison between treatments was performed on difference (delta) between measurements at time 0 and at baseline, and on slopes obtained by fitting measurements after unclamping with a linear regression model. At unclamping no difference in delta for plasma glutathione redox ratio (oxidised/total glutathione, %) was observed between treated and control groups with low ejection fraction (delta = 16 (SD 8.39) and 24 (7.0) redox ratio %, respectively). Baseline value recovery rate (redox ratio %/min) was significantly faster in treated v control patients (slope -0.912 (0.380) v -0.158 (0.200), P < 0.005, respectively). Cardiac index showed a trend to greater improvement in the treated group (slope 0.04 (0.03) v 0.003 (0.002) 1/min/m2/h, P < 0.02, treated v controls, respectively). In patients with normal ejection fraction, leucocyte depletion did not result in significant improvement v controls. Leucocyte depletion seems to provide benefit only in patients with left ventricular dysfunction.

Although there are various descriptive reports concerning exercise-induced gastrointestinal distress, the role of gastrointestinal hormones and/or enzymes is not definitively established. In this study we investigated the behaviour of pepsinogens (PGI and PGII) after an endurance race performed at an altitude of 4,300 m by 13 well-trained marathon runners, with the aim to establish their interrelationship with gastrointestinal distress and with the modifications of gastrin and cortisol. The athletes showed a significant rise in gastrin (p < 0.01) and in cortisol (p < 0.01) and a significant decrease in PGI (p < 0.01) and PGII (p < 0.05) after the race. The PGI/PGII ratio presented small variations indicating that heavy exercise has less effects on PGs than those observed for gastrin. Gastrointestinal symptoms occurred in 6 athletes (46%) during the race and in 8 athletes (62%) after the race. No relationship was found between gastrointestinal symptoms and hormonal modifications after the race. A control group of 5 subjects was used: they (n = 5) did not show any significant modification of gastrin and PGs during the period spent at the above altitude, indicating that travel, altitude and acclimatization, food and beverages, do not influence the behaviour of these hormones. Conversely, they presented a significant decrease of cortisol (p < 0.05) linked to the circadian rhythm. The data of the present study indicate that the potential damage of gastrointestinal apparatus in mountain marathon runners is not related to the above mentioned hormones.

Diabetes has been claimed to be a risk factor for pancreatic carcinoma, but it is probably a consequence of gland invasion from the neoplastic tissue. A link between diabetes and pancreatic carcinoma was suggested by means of biochemical markers of the diseases, namely glycated hemoglobin and CA19.9. Moreover, CA19.9 was proposed as a sensitive and useful marker of the severity of exocrine damage in diabetes, since the mucin decreased when metabolic compensation improved. We examined 64 diabetic patients (36 insulin dependent, 16 non insulin dependent, 12 treated with diet) by measuring CA19.9 using two different immunometric methods and glycemia and glycated hemoglobin. We observed that a correlation between CA19.9 and biochemical markers of metabolic compensation of diabetes was inexistent and no differences between insulin dependent and non insulin dependent patients were found. A high concentration of CA19.9 in a diabetic patient should be interpreted and evaluated in the same manner as for a non diabetic patient.

The ceftazidime concentration in agar plates inoculated with Pseudomonas aeruginosa was determined by high-performance liquid chromatography at fixed points (3, 6, 9, 12, and 15 mm) from the disk center and at fixed times (2, 4, 6, 16, and 24 h) to study the antibiotic kinetics of diffusion. A statistical difference between the concentrations determined in the presence of microorganisms and in uninoculated plates after 16 and 24 h was evidenced and was probably ascribable to the drug hydrolysis carried out by the induced beta-lactamase.

A multicentre trial of Capture Assay Radim Liquid Allergen was performed to define the sensitivity, specificity and clinical reliability of the system in diagnostic allergology. The results of the evaluation were compared with clinical data and in vivo testing. Good agreement was obtained for Dermatophagoides pteronyssinus (D1), Cat's epithelium (E1), Betula verrucosa (T3) and Olea europea (T9), Artemisia vulgaris (W6) and Parietaria officinalis (W19). Some spreading of data was observed for Artemisia absinthium (W5), Cynodon dactylon (G2), and Lolium perenne (G5). We found a high number of negative cases for Alternaria alternata (M6). The advantages offered by the system are the automation, the small quantity of serum requested, the supply of quantitative results in international units of specific IgE, the user-friendly software. The data are sufficiently reliable for the diagnostic system to be introduced into the clinical laboratory allergological routine.

This HPLC assay with o-phthalaldehyde precolumn derivatization is used to measure the total, oxidized, and protein-bound forms of glutathione in human blood, plasma, and rat tissue. Total glutathione (i.e., sum of reduced, oxidized, and protein-bound fractions) was determined after reduction with dithiothreitol and protein precipitation with perchloric acid (PCA). A preliminary selective blockage of free sulfhydryl groups with N-ethylmaleimide was necessary to evaluate the different oxidized forms. The assay showed high sensitivity (< 0.05 pmol injected) and good precision (within-day CVs of 5.5% to 6.4%), recovery (101% +/- 4%), and linearity (r > 0.999). Samples, after PCA acidification, were stable at room temperature and 4 degrees C for 3 days, and at -20 degrees C and -80 degrees C for > 1 month. The method (involving automated derivatization) not only is very rapid and simple but also allows immediate processing of many different biological samples.

We compared four fully automated systems (Boehringer ES700, Tosoh AIA1200, Bayer Immunol, Mitsui Quartus) using 50 routine sera that included both euthyroid and pathological (with various degrees of hyper- or hypothyroidism) samples. The comparisons among systems by linear regression analysis yielded contradicting results, especially for fT4. Using the reference values of fT4 and TSH recommended from the manufacturers, the systems agreed completely in classification of patients in 32 cases; three systems agreed in seven cases, and two systems agreed in 10 cases; in one case, they completely disagreed. The agreement among the four systems we studied was high and would allow their introduction and use for routine thyroid screening. Comparison tests among fully automated systems for fT4 and TSH should not be determined only by linear regression statistical method, but additional functional validations must be performed.