Detection of alkaline sphingomyelinase activity in human stool: proposed role as a new diagnostic and prognostic marker of colorectal cancer.

OBJECTIVES: Intestinal alkaline sphingomyelinase, by exerting a major role in dietary sphingomyelin digestion, is responsible for the generation of messengers able to trigger the rapid turnover and apoptosis in intestinal epithelial cells. Markedly reduced mucosal alkaline sphingomyelinase activity has been associated with human colorectal neoplasms. The aim of this study was to analyze the alkaline sphingomyelinase activity in feces from healthy subjects and colorectal adenocarcinoma patients and to correlate it with the enzyme activity in intestinal tissues. MATERIALS AND METHODS: The enzyme activity was measured both in the intestinal samples from 12 healthy controls and 51 patients with colorectal adenocarcinoma (tumoral and paratumoral tissue) and in the fecal samples of 34 healthy subjects and 29 patients with adenocarcinoma. The relation between sphingomyelinase activity and Dukes' stage, cell differentiation degree, age, and gender was also analyzed. RESULTS: Alkaline sphingomyelinase was significantly decreased (P < 0.001; mean reduction >90%) in tumoral intestinal mucosa of patients compared with controls independently of Dukes' stage and tumor differentiation grade. Interestingly, the enzyme activity in histologically normal paratumoral tissues was statistically lower than control samples (P < 0.001). As occurs in neoplastic tissues, a relevant mean reduction (P < 0.0001; almost 90%) of alkaline sphingomyelinase was revealed in stool samples from tumor patients when compared with controls. CONCLUSION: These findings may have implications for cancer biology and perhaps also for the design of clinical test, thus suggesting that the fecal sphingomyelinase activity could really reflect the human intestinal mucosa enzyme level and could represent a new marker for human colorectal adenocarcinoma, mainly taking into account its early appearance in intestinal neoplasms.     

Urinary incontinence after radical vulvectomy treated with Macroplastique implantation

Postradical vulvectomy urinary incontinence is a common surgery-related complication, especially after subtotal urethrectomy. However, only 1 trial has been reported in the previous literature that described a case of total urinary incontinence treated with an Aldridge sling operation. We present 2 cases of patients affected by postradical vulvectomy, with partial urethral resection and total incontinence successfully treated by transurethral Macroplastique injection. This procedure could be considered as a valid, minimally invasive surgical option to improve the well-being of patients with vulvar cancer affected by postradical vulvectomy urinary incontinence, especially in elderly patients at high operative risk.     

Global migration from plastic materials into olive oil and isooctane: an experimental comparison

Global migration from several plastics (phthalate-plasticized PVC, polyurethane, polyether-polyamide copolymer and silicone rubber) into olive oil, used as a liquid simulant for fatty foods, was compared with global migration into isooctane, which has been proposed as a new fatty-food simulant. The results showed that the isooctane test (involving contact for 2 hr at 40 degrees C) is not suitable as a substitute for the olive oil test (contact for 10 days at 40 degrees C) for some types of commercial plastic materials.     

Dopamine-induced migrating myoelectrical complex-like activity in human duodenum

The effect of dopamine on human gastric and small intestinal interdigestive motility was investigated in 12 subjects. Intestinal motility was recorded by means of a four-lumen polyvinyl probe with four open tips located 15 cm apart, continuously perfused with distilled water. In each subject during the same study, after recording two consecutive spontaneous phase III of migrating myoelectrical complexes and when a phase II appeared, dopamine was infused intravenously twice in a dose of 5 g/kg/min for 15 min with an interval of 20 min between each infusion. In six subjects, the second dopamine infusion was preceded by a treatment with sulpiride (10 mg, intravenously, as bolus) or domperidone (10 mg, intravenously, as bolus), each considered a highly selective dopamine antagonist. The results show that dopamine stimulates duodenal motility producing a pattern similar to that observed in phase III of spontaneously occurring migrating myoelectrical complexes. The second dopamine infusion reproduced in all cases the same pattern of motility as observed during the first infusion. Sulpiride and domperidone prevented the effect of dopamine in all cases. It is therefore suggested that dopamine-induced duodenal motility may involve specific dopaminergic receptors.     

Rifaximin in patients with lactose intolerance

BACKGROUND: Abdominal symptoms linked to lactose malabsorption may be caused by metabolic activity of colonic bacteria. Rifaximin, a non-absorbable rifampycin derivative, is active against colonic bacteria, it may be useful in the treatment of lactose intolerance. AIM: The aim of this study has been to evaluate short-term rifaximin therapy in patients with lactose intolerance. METHODS: Thirty-two patients with lactose intolerance diagnosed using the hydrogen lactose breath test were studied. Fourteen patients received rifaximin 800 mg/day for 10 days, 13 patients followed a diet without milk for 40 days and 5 patients received a placebo for 10 days. Total breath H(2) excretion expressed as area under the curve, and the symptom score were evaluated in all patients at the start, and subsequently after 10 and 40 days. RESULTS: In the 14 patients who received rifaximin for 10 days, area under the curve at day 10 and day 40 was statistically significantly lower than the one computed at basal (P<0.01). Diet reduced area under the curve progressively reaching statistical significance at day 40, while the placebo did not change area under the curve throughout the study. The total symptom score significantly improved after rifaximin and diet. CONCLUSION: In patients with lactose intolerance, a 10-day therapy with rifaximin as well as 40-day diet without lactose reduces the area under the curve and the symptom score.     

Enhanced release of atrial natriuretic factor during exercise-induced myocardial ischaemia in patients after acute myocardial infarction.

To determine whether acute myocardial ischaemia induced by dynamic exercise can lead to changes in plasma levels of atrial natriuretic factor, we performed symptom-limited bicycle electrocardiographic tests in 20 males with recent acute myocardial infarction and in 8 control males. Ten patients developed exercise-induced myocardial ischaemia and 10 patients did not. There were no significant differences between the two groups with regard to age, site of myocardial infarction, urinary sodium, atrial sizes, radionuclide left ventricular ejection fraction, workload, baseline and peak-exercise heart rate, baseline and peak-exercise rate-pressure product, duration of exercise. Also baseline atrial natriuretic factor concentrations were similar in both groups (ischaemic patients: 34.51 +/- 15.73 pg/ml; nonischaemic patients: 27.17 +/- 8.74 pg/ml, NS), while peak-exercise atrial natriuretic factor concentrations were higher in patients with exercise-induced myocardial ischaemia (112.31 +/- 35.5 pg/ml) than in the others (80.46 +/- 23.43 pg/ml) (P less than 0.05). After 15 minutes of recovery, plasma atrial natriuretic factor levels were still raised only in the ischaemic patients (63.3 +/- 15.44 pg/ml, P less than 0.01), returning to baseline after 30 minutes in both groups. In control subjects, the behaviour of atrial natriuretic factor resembled that of the patients without exercise-induced ischaemia, with a significant increase at peak-exercise (from baseline levels of 23.1 +/- 10.5 pg/ml to peak-exercise levels of 91.3 +/- 14.5 pg/ml, P less than 0.0005) and a rapid return to baseline levels after 15 minutes of recovery (28.5 +/- 10.6 pg/ml, NS).(ABSTRACT TRUNCATED AT 250 WORDS)     

Lidocaine, mexiletine and propafenone in the treatment of arrhythmias complicating myocardial infarction. A case report

We describe a case of acute myocardial infarction complicated by atrial and ventricular arrhythmias in which it was possible to verify the effectiveness of lidocaine, mexiletine and propafenone. Intravenous administration of mexiletine was ineffective both on atrial and ventricular rhythm disturbances. The lidocaine therapy reduced ventricular ectopic frequency, but did not prevent the appearance of several paroxysms of atrial fibrillation. Intravenous infusion of propafenone, 11 micrograms/kg per min, after a 1 mg/kg i.v. bolus, immediately and completely suppressed atrial arrhythmias. The increase in infusion rate up to 22 micrograms/kg per min also suppressed ventricular ectopy. This dosage of propafenone did not provoke serious adverse effects in our patient.     

Comparative ecotoxicity of single and binary mixtures exposures of cadmium and zinc on growth and biomarkers of Lemna gibba

In the present study, single and mixture effects of cadmium (Cd) and zinc (Zn) on Lemna gibba were analyzed and compared using growth parameters, based on frond number and fresh weight, and biochemical parameters, such as pigment, protein content and activity of antioxidant enzymes. Plants were exposed for 7 days to these metals in nutrient solution. Single and mixture exposures affected plant growth and the biomarkers of the antioxidant response. Considering the growth parameters, Cd was found to be much more toxic than Zn. IC50-7d, based on growth rate calculated on frond number, were 17.8 and 76.73 mg/L, and on fresh weight were 1.08 and 76.93 mg/L, for Cd and Zn respectively. For Cd, LOEC values were obtained at 2.06 and 1.03 mg/L, for frond number and fresh weight respectively; while for Zn, at 20.1 and 74.6 mg/L. A high toxicity effect, considering the same response variables, was observed in plants exposed to the mixtures. Three fixed ratios, based on toxic units (TU) were assayed, ratio 1: 2/3 Cd−1/3 Zn, ratio 2: 1/2 Cd−1/2 Zn and ratio 3: 1/3 Cd−2/3 Zn. Ratio 3 (where Zn was added in higher proportion) was the less toxic. All concentrations of Ratio 1 and 2 significantly inhibited plant growth, showing a 100% inhibition of growth rate at the highest concentrations when based on frond number. Catalase (CAT; EC 1.11.1.6), ascorbate peroxidase (APOX; EC 1.11.1.11) and guaiacol peroxidase (GPOX; EC 1.11.1.7) activities in single metals assays were higher than controls. In mixture tests, the activity of APOX and GPOX was significantly stimulated in plants exposed to all evaluated combinations, while CAT was mainly stimulated in Ratio 3. It was observed that the activity of the enzymes was increased in the mixtures compared with similar concentrations evaluated individually. APOX activity was observed to fit the CA model and following a concentration-response pattern. The response of this antioxidant enzyme could serve as a sensitive stressor biomarker for Cd–Zn interactions. Frond number in Cd–Zn mixtures was not well predicted from dissolved metal concentration in solution using concentration addition (CA) as reference model, as results showed that toxicity was more than additive, with an average of ΣTU = 0.75. This synergistic effect was observed up to 50 mg Zn/L in the mixture, but when it was present in higher concentrations a less than additive effect was observed, indicating a protective effect of Zn. A synergistic and dose-ratio deviations from CA model were also observed.