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We present the results of the co-phasing closed loop performed with a pyramid wavefront sensor for what we believe to be the first time in the presence of emulated atmospheric disturbance. The performance of the co-phasing loop is significantly improved by applying two spatial filters in the sensor signal space. The first is a zonal filter applied to the interaction matrix before the computation of the reconstructor; the second is a modal filter applied to the sensor signals before the correction command computation. The presented laboratory results demonstrate that, applying both filters, the time requested to average out the atmospheric disturbance in each loop step is reduced by 2 orders of magnitude, improving the loop stability and accuracy.

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We report what is to our knowledge the first laboratory experiment that shows the use of a pyramid wavefront sensor to cophase and align segmented mirrors having three degrees of freedom per segment, i.e., piston, tip, and tilt. In the laboratory the iterative alignment procedure reached a wavefront residual error of about 10 nm. The residual error was equally distributed between piston, tip, and tilt. These results demonstrate that the pyramid can successfully simultaneously sense the piston, tip, and tilt of a segmented mirror. This last feature makes this technique very attractive in phasing and aligning astronomical segmented telescopes such as extremely large telescopes currently under extensive studies.

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The diagnosis of bowel infarction is still a challenge. In some cases, portal venous gas is an associated feature and in these patients, the prognosis is very poor. We report on our experience with two consecutive cases in which ultrasonography showed gas in the portal venous branches, and also in the hepatic veins in one of them. At laparotomy, advanced bowel necrosis was found, and both patients died within 24 hours. Other cases of portal venous gas associated with bowel infarction have been reported, but this is the first report of gas also being found in the hepatic veins. There may be a relationship between the amount of gas in the intrahepatic veins and the stage of bowel ischemia. Confirmation of this might improve the selection of patients and eliminate unnecessary procedures.

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We report a case of drain-site tumour recurrence 2 years after right colon resection for adenocarcinoma of the ascending colon. A large number of case reports concerning port-site tumour recurrences after laparoscopic procedures have been reported. However, post-laparotomy incision site cancer recurrence is considered a rare occurrence.

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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.

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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.

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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.

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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)

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The authors give a brief review of the course of surgical treatment for colon cancer in the last two decades, as reported in the medical literature. Between 1960 and 1980 they examined 619 patients. Of these, 599 underwent surgery: 436 (72.8%) had radical surgery and 163 (27.2%) received palliative operations. The morbidity was 12.1% and the mortality 2.7%. Sixty per cent of the patients in Dukes' class "A" and "B" were alive after five years, against 28% of those in class "C" and non in class "D". The results obtained during the 1970 to 1980 period are not significantly better than those obtained from 1960 to 1969. On the basis of this experience, the authors describe their present approach for the treatment of tumors of the colon and explain in detail the preoperative preparation of the patients, the extension of the excisions and of the lymphectomies, according to the site of the cancer and its local or distant invasion, the use of temporary derivative colostomies and the application of additional medical therapies. Guidelines for reaching an early diagnosis of colon carcinoma are given, in order to improve the postoperative survival rate.

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From 1960 to December 1977, 251 patients with renovascular hypertension (RVH) were observed; 219 were operated upon. Long-term results were assessed in 130 patients. Selection for surgery follows three steps: 1) screening of patients with renal artery disease, which is done by angiography; 2) diagnosis of RVH, which is reached mainly by differential renal function studies and renal vein renin measurements (ancillary methods are intravenous pyelography and sequential scintigraphy; the significance of renin measurements is discussed); and 3) prediction of the results of surgery and choice of technique. An original dynamic test of the authors is employed and reconstruction of the renal artery is the procedure of choice. This is done in the majority of cases by aortorenal bypass grafts using dacron prostheses. Techniques and complications are discussed and comparison with venous autograft is made. Hospital mortality was 3.2%. Overall long-term results were favorable in 78%. Long-term mortality was 6% and occurred mainly in patients who remained hypertensive. Results in atherosclerotic patients are compared with those obtained in fibrous stenoses. Results of renal artery reconstructions were far better than those of nephrectomies and lead us to restrict indications for such a procedure.

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