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P Stefanini

Publications and source records attributed to P Stefanini.

At least 19 recordsLinked to original sources
PubMed1992

In human monocytes interleukin-1 stimulates a phospholipase C active on phosphatidylcholine and inactive on phosphatidylinositol.

Interleukin-1 (IL-1) can initiate the synthesis of prostaglandins which in turn act as endogenous modulators of IL-1 production. The human monocyte/macrophage synthesizes various eicosanoids through the activation of the cellular phospholipase system. Cell stimulation results in the activation of phospholipase A2 (PLA2) whose major substrate is phosphatidylcholine (PC) and the release of the eicosanoid precursor arachidonic acid (AA) from PC. Another pathway is the stimulation of a phospholipase C (PLC) mainly active on phosphoinositides and the resulting formation of inositol phosphates (IPs) and diacylglycerol (DAG). Phospholipids other than phosphoinositides can also be hydrolysed by PLC to give rise to DAG. Studies have shown that IL-1 does not activate the IP pathway, but it primarily stimulates a PLC linked to phosphatidylethanolamine in cultured rat mesangial cells, and a PLC linked to PC in Jurkart cells. We have stimulated human monocytes with IL-1 and calcium ionophore A23187 and we have observed their effect on the phospholipase system. The results indicate that IL-1 does not activate the formation of IPs in cells labeled with [3H]myo-inositol. In contrast, in cells labeled with [3H]AA, IL-1 causes the formation of DAG associated with the hydrolysis of PC. Moreover, after stimulation with IL-1 there is no accumulation of free AA which would indicate that there has been no activation of PLA2, which occurs instead with A23187 stimulation. These data suggest that, in monocytes, IL-1 does not directly stimulate a PLA2 or a PLC active on phosphatidylinositol; instead it primarily stimulates a PLC active on PC.

Calcimycin↗
PubMed1990

[Analysis of temporal distribution of suicides. Methodological notes on comparison of dates of death and dates of suicidal act].

The short-term temporal cycles in the frequency of suicide for the Province of Florence 1985-1987 has been analyzed. The authors initially present a comparison between the Date of Suicidal Act and the recorded Death Certificate Date. In their data the difference, still debated in the literature, appears of no practical importance. The results show that suicides peak on Spring and Fall, with a temporal variation with regard to the first decade of the month, high at the beginning and low at the end. No evident pattern has been explained by day of the week, unlikely any reports from the literature. On the contrary, the effect of the National Holidays are striking, showing a decrease on the holidays and a sharp rise on the subsequent day.

Death Certificates↗
PubMed1986

[The technic of sub-vigil anesthesia in plastic-reconstructive surgery].

The personal experience in plastic-reconstructive surgery with 395 cases of sub-vigil anaesthesia (neuroleptanalgesia + benzodiazepine in 124 patients (group A); ketamine + benzodiazepine in 138 patients (group B); neuroleptanalgesia + ketamine + benzodiazepine in 133 patients (group C) is described by the authors in the present study. They conclude that the sub-vigil anaesthesia is usually free from complications and a very safe, tolerable, expedient technique for plastic surgical procedures; furthermore, the result is good patient acceptance, a stable blood pressure and heart rate.

Adolescent↗
PubMed1985

A reappraisal of the factors affecting early patency of aortocoronary saphenous vein bypass grafts. Current experience with extensive revascularization employing sequential grafting techniques.

A number of factors potentially influencing the patency rates of aortocoronary bypass grafts were investigated in a consecutive series of 50 patients by control angiography at 28 +/- 26 days and by univariate and multivariate analysis of a selected set of clinical, surgical and angiographic predictors. There were 234 anastomoses in this series, a mean of 4.7 per patient (range 1 to 9), 215 of which were connected to sequential vein grafts. After surgery, 40 patients were treated with anticoagulants and/or platelet inhibitors. Of the 234 coronary anastomoses studied, 219 were patent (93.6%). Coronary artery diameter, patient's age and previous myocardial infarction were shown to be independent predictors of increased risk of anastomotic occlusion. Arteries less than 1.5 mm in diameter had a patency rate of 84.9%, versus 96.1% for vessels 1.5 mm or larger (p = 0.009). The use of side-to-side anastomoses with sequential grafts seemed to counterbalance the unfavourable effect of small arterial size. Patients aged 65 or older had a lower probability of having all their grafts patent than younger patients did (50 vs 89%, p = 0.01). Patients with previous myocardial infarction similarly had a lower probability of having all their grafts patent compared to patients without previous infarction (68 vs 95%, p less than 0.05); this correlation was explained by a more frequent occlusion rate of grafts directed to fibrotic left ventricular areas. The effect of anticoagulants and of platelet-inhibitors was favourable, but did not reach statistical significance.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1977

Transduodenal sphincteroplasty.

Sphincteroplasty is an inferior partial sphincterotomy followed by suture approximation of both the duodenal and common bile duct walls. We have described our operative technic employed in 770 sphincteroplasties performed in the past 14 years.

Ampulla of Vater↗
PubMed1976

The value of arteriography in the diagnosis and treatment of insulinomas.

Six arteriograms were performed in five patients with insulinoma. The method showed with precision the size and location of the tumor in five instances, whereas in one instance the method was unsuccessful. Arteriography was performed again with more refinements in technic, but was adequate in locating only the largest tumor. Since diagnostic accuracy of arteriography depends on the size of the tumor, and nonpalpable tumors are only occasionally located, the main problems in surgical treatment of insulinomas are unresolved.

Adenoma, Islet Cell↗
PubMed1975

Roux-en-Y hepaticojejunostomy: a reappraisal of its indications and results.

A critical evaluation is made of 131 patients submitted to choledocho or hepaticojejunostomy. The main indications for hepaticojejunostomy were iatrogenic strictures of CBD (60 patients), and choledocholithiasis with markedly dilated duct (41 patients). The overall mortality rate was 4% representing principally renal hepatic failure, bile peritonitis and bleeding. The complications following hepaticojejunostomy included only in one case biliary fistula which required reoperation. The long-term results of 80 patients available for a followup study were as follows: 63 patients (78.7%) were symptom-free at 2-13 years followup; 8 patients had brief episodes of cholangitis which responded to antibiotic and corticosteroid treatment; 9 patients required reoperation for stricture of anastomosis. These overall results are a strong argument for hepaticojejunostomy which, compared with choledochoduodenostomy, avoids the hazards of the so-called sump syndrome and of the reflux of enteric contents in the CBD. An increased incidence of peptic ulcer disease in the patients submitted to hepaticojejunostomy was not observed. In very high strictures and in reinterventions anastomosis between left hepatic duct and Roux-en-Y jejunal limb was carried out. The results achieved with this technique, which was performed in 26 patients, were about the same following hepaticojejunostomy.

Adult↗