Differences in clinicopathological features and distribution of risk factors in Italian melanoma patients.

BACKGROUND: No studies are available in the literature on the distribution of different melanoma features and risk factors in the Italian geographical areas. OBJECTIVE: To identify the differences in clinical-pathological features of melanoma, the distribution of risk factors and sun exposure in various Italian macro-areas. METHODS: Multicentric-observational study involving 1,472 melanoma cases (713 north, 345 centre, 414 south) from 26 referral centres belonging to the Italian Multidisciplinary Group for Melanoma. RESULTS: Melanoma patients in northern regions are younger, with thinner melanoma, multiple primaries, lower-intermediate phototype and higher counts of naevi with respect to southern patients; detection of a primary was mostly connected with a physician examination, while relatives were more involved in the south. Northern patients reported a more frequent use of sunbeds and occurrence of sunburns before melanoma despite sunscreen use and a lower sun exposure during the central hours of the day. CONCLUSIONS: The understanding of differences in risk factors distribution could represent the basis for tailored prevention programmes.

Degree correlations in random geometric graphs.

Spatially embedded networks are important in several disciplines. The prototypical spatial network we assume is the Random Geometric Graph, of which many properties are known. Here we present new results for the two-point degree correlation function in terms of the clustering coefficient of the graphs for two-dimensional space in particular, with extensions to arbitrary finite dimensions.

Dynamics of unperturbed and noisy generalized Boolean networks.

For years, we have been building models of gene regulatory networks, where recent advances in molecular biology shed some light on new structural and dynamical properties of such highly complex systems. In this work, we propose a novel timing of updates in random and scale-free Boolean networks, inspired by recent findings in molecular biology. This update sequence is neither fully synchronous nor asynchronous, but rather takes into account the sequence in which genes affect each other. We have used both Kauffman's original model and Aldana's extension, which takes into account the structural properties about known parts of actual GRNs, where the degree distribution is right-skewed and long-tailed. The computer simulations of the dynamics of the new model compare favorably to the original ones and show biologically plausible results both in terms of attractors number and length. We have complemented this study with a complete analysis of our systems' stability under transient perturbations, which is one of biological networks defining attribute. Results are encouraging, as our model shows comparable and usually even better behavior than preceding ones without loosing Boolean networks attractive simplicity.

Evaluation of venous and arterial conduit patency by 16-slice spiral computed tomography.

BACKGROUND: Computed tomography has been shown to be useful in the evaluation of aortocoronary bypass grafts (CABG). This is the first prospective study to evaluate the accuracy of a new-generation scanner in the detection of patency and significant stenoses (>50% decrease in diameter) of venous and arterial grafts in patients with previous CABG. METHODS AND RESULTS: In 96 patients (80 males, mean age 62 years) with previous CABG, a multislice computed tomography (MSCT) scan was performed (collimation 16x0.625 mm). Patients with atrial fibrillation, renal failure, severe respiratory disease, severe heart failure, heart rate >70 bpm despite therapy, or unstable angina were excluded. A total of 285 conduits implanted on the native coronary arteries at the time of CABG were evaluated. MSCT data were analyzed by 2 independent radiologists and compared with the results of conventional angiography. Three patients were excluded from analysis. All conduits were judged evaluable in 84 patients. Among these patients, MSCT correctly diagnosed 54 occluded grafts and 4 significant stenoses on the body of the grafts. Of the 17 significant anastomotic lesions, MSCT correctly diagnosed 15. For these 84 patients, diagnostic accuracy was 99%, sensitivity was 97%, and specificity was 100%. When all 93 patients were considered, the sensitivity of MSCT in diagnosing significant stenoses was 96%. CONCLUSIONS: MSCT with the new-generation scanner allows for accurate assessment of venous and arterial conduits in patients with previous CABG with a high degree of sensitivity and specificity. Exclusion criteria and radiation exposure remain limitations of the method.

Multidetector row CT coronary angiography: technique and preliminary experience.

PURPOSE: To report our preliminary experience with multi-slice spiral CT coronary angiography of the coronary arteries. MATERIALS AND METHODS: 50 volunteers (mean age 61 years, range 45-72) with baseline heart rates below 70 bpm underwent multi-detector row CT coronary angiography (GE Light Speed Plus, 140 kVp, 270 mA, 1.25-mm collimation, 0.5-second rotation time, high quality pitch) with retrospective ECG gating after receiving 140-150 ml of iodinated contrast medium (Iopamiro 300 mg-dl, Bracco, Italy) at a flow rate of 4 ml/sec. Three of the 50 patients had previously undergone coronary procedures (1 anterior descending artery stent, 1 left circumflex artery stent and 1 anterior descending artery percutaneous angioplasty) and three were undergoing follow-up examinations after by-pass surgery. The remaining 44 patients were asymptomatic and had no history of coronary artery disease. All CT angiograms were back-reconstructed from 20 to 80% of the diastolic cycle with 10% increments to establish the phase with fewer "stair-step" motion artefacts for each artery. Patients with heart rates above 70 bpm were administered beta-blockers during the five days preceding the examination in doses appropriate for the patient's clinical characteristics. RESULTS: The CT room occupation time ranged from 25 to 35 minutes (mean time 27') and the post-processing time from 30 to 60 minutes (mean time 40'). The left anterior descending artery was best visualised in middle diastole (70% of cardiac cycle), the circumflex artery at 60% of the cardiac cycle, and the right coronary artery at 40%. Out of 132 arteries, 19 (14.4%) were considered non-assessable due to "stair-step" motion artefacts, whereas 2 (1.5%) were only partially visualised owing to the presence of extensive wall calcifications. Among the 113 assessable arteries, we observed: 72 normal coronary arteries without stenosis or wall calcifications (54.5%); 28 arteries with minimal wall irregularities and stenoses below 50% (21.2%); 7 stenoses >50% involving the right coronary artery (no. 2), the anterior descending arteries (no. 4) and the left circumflex artery (no. 1) (5.3%). In the remaining 6 patients, optimal visualisation of the stents and venous and arterial surgical by-passes was obtained. CONCLUSIONS: Although further larger-scale studies are required to compare MSCT coronary angiography with CT coronary angiography, the application of MSCT technology to the study of the coronary arteries is a promising technique with a good potential for use in routine clinical practice. In selected patients (with baseline heart rates <70 bpm, or after beta-blocker therapy) it is able to provide very interesting results and could be used as a method of choice for following patients after interventional procedures or as a mass-screening tool to select patients to be referred for coronary angiography.

A statistical study of a class of cellular evolutionary algorithms.

Parallel evolutionary algorithms, over the past few years, have proven empirically worthwhile, but there seems to be a lack of understanding of their workings. In this paper we concentrate on cellular (fine-grained) models, our objectives being: (1) to introduce a suite of statistical measures, both at the genotypic and phenotypic levels, which are useful for analyzing the workings of cellular evolutionary algorithms; and (2) to demonstrate the application and utility of these measures on a specific example-the cellular programming evolutionary algorithm. The latter is used to evolve solutions to three distinct (hard) problems in the cellular-automata domain: density, synchronization, and random number generation. Applying our statistical measures, we are able to identify a number of trends common to all three problems (which may represent intrinsic properties of the algorithm itself), as well as a host of problem-specific features. We find that the evolutionary algorithm tends to undergo a number of phases which we are able to quantitatively delimit. The results obtained lead us to believe that the measures presented herein may prove useful in the general case of analyzing fine-grained evolutionary algorithms.

The eosinophil and the eye.

Personal studies in allergic eye diseases reviewed in this paper indicate that: 1. An increased number and an abnormal distribution of eosinophils is present in conjunctival biopsies of patients with vernal keratoconjunctivitis (VKC). 2. Eosinophil and eosinophil products, such as ECP, are also increased in tears of VKC patients and, in hay fever conjunctivitis, accumulate during the late-phase of allergic reaction following specific allergen challenge. 3. Circulating eosinophils of VKC patients show a typical activation phenotypic profile which is associated with increased serum level of eosinophil cationic protein and eosinophil-derived neurotoxin/protein X. A clinical study of the modulatory effect of cetirizine on the early and late phase of the allergic reaction as well as on the eosinophil activation and tissue recruitment following conjunctival allergen challenge is reported as an example of the need to evaluate eosinophil functions when investigating anti-allergic drugs. Drugs modulating various aspects of eosinophil function could play a primary role in the treatment of allergic eye disease.

Serum levels of eosinophil cationic protein in allergic diseases and natural allergen exposure.

BACKGROUND: Eosinophil cationic protein (ECP) is a cytotoxic performed mediator stored in eosinophil granules and released under various in vitro and in vivo conditions. OBJECTIVE: This study was carried out to evaluate the clinical value of ECP as a marker of allergic inflammation. METHODS: ECP was measured by a competitive radioimmunoassay in serum samples from 265 patients and 45 matched control subjects and related to the type of allergic disease (asthma, rhinitis, conjunctivitis) and to the type of allergic sensitization. RESULTS: All the patient groups studied showed significantly higher levels of serum ECP than control groups (p < 0.001). The type of sensitization was shown to be the only variable influencing ECP serum levels. In fact, subjects sensitized to perennial allergens had significantly higher ECP values than subjects with seasonal allergy (p < 0.001), whereas in patients with seasonal allergy ECP levels were significantly increased only during the pollen season. Differences in ECP values between various allergic diseases or age groups were only due to a nonhomogeneous distribution of the type of sensitization or to time of sera collection. CONCLUSIONS: Results obtained indicate that persistent natural exposure to a sensitizing allergen is responsible for a measurable increase in serum ECP levels in patients with allergy.

Increased serum levels of eosinophil cationic protein and eosinophil-derived neurotoxin (protein X) in vernal keratoconjunctivitis.

PURPOSE: To evaluate whether the eosinophil preformed mediators, eosinophil cationic protein X, and eosinophil-derived neurotoxin/eosinophil protein X (EDN/EPX) are detectable in serum and can be used as markers of eosinophilic inflammation. METHODS: A competitive radioimmunoassay was used to detect serum levels of eosinophil cationic protein and EDN/EPX in 31 patients with vernal keratoconjunctivitis (VKC) and in 15 healthy controls. RESULTS: Mean serum levels of both eosinophil cationic protein and EDN/EPX were significantly higher in patients with VKC than in controls. There was a good correlation between serum levels of eosinophil cationic protein and EDN/EPX. No significant difference in mean serum eosinophil cationic protein levels was observed between patients with positive radioallergosorbent test (RAST) results and those with negative RAST results who have VKC, whereas mean EDN/EPX and total immunoglobulin E serum levels were significantly higher in patients with positive RAST results than in those with negative RAST results who have VKC. Serum eosinophil cationic protein, but not EDN/EPX, levels were significantly related to total immunoglobulin E levels. CONCLUSION: The authors' data indicate that serum levels of eosinophil cationic protein and EDN/EPX are useful markers of eosinophilic ocular inflammation in VKC.

[A non-Q wave myocardial infarct with an up or down shift of the ST segment in the acute phase: the clinical, echocardiographic, ergometric and coronary angiographic correlates]. / Infarto miocardico senza onde Q con sopra o sottoslivellamento del tratto ST in fase acuta: correlati clinici, ecocardiografici, ergometrici e coronarografici.

To assess the significance of ST segment shift during the acute phase of non-Q myocardial infarction we studied the clinic echocardiographic, ergometric and coronarographic findings of 46 patients with a first non-Q wave myocardial infarction. The study population was subdivided in 2 subgroups on the basis of acute electrocardiographic change (Group I with ST elevation, Group II with ST depression). Patients with ST elevation had little myocardial infarction with enzymatic (early CPK peak) and coronarographic (low prevalence of coronary occlusion) signs of early spontaneous fibrinolysis. The second group had more diffuse myocardial infraction, higher prevalence of multivessel coronary disease and positive stress test. The ECG changes in this subgroup an probably due to subendocardial necrosis for the presence of collateral flow. The worse intrahospital prognosis of patients with ST segment depression may be related to cardiac function and age.

Markers of eosinophilic inflammation in allergic diseases.

The paper reviews personal studies aimed at identifying clinical markers of eosinophil inflammation in allergic diseases. Preliminary data on the use of flow cytometry as a method to detect eosinophil activation through phenotypic activation markers are reported. The concept of eosinophil releasibility is introduced on the basis of in vitro eosinophil activation and mediator release by different stimuli. Data showing an increase of serum levels of ECP mainly in subjects with sensitivity to perennial allergens and related to histamine bronchial reactivity are discussed in view of their practical impact in diagnosing and monitoring of allergic diseases and asthma.

Release of granule proteins by eosinophils from allergic and nonallergic patients with eosinophilia on immunoglobulin-dependent activation.

The release of eosinophil peroxidase (EPO) and eosinophil cationic protein (ECP) was evaluated after incubation of eosinophils (EOSs) from allergic subjects with the specific allergen or with anti-IgE monoclonal antibodies (MAbs). High levels of EPO could be released after addition of the specific allergen (and not unrelated ones) or anti-IgE MAb. Moreover, EPO release with the two stimuli was significantly correlated both in allergic and in nonallergic patients. In the same supernatants, another granule protein, ECP, could not be detected, suggesting a lack of correlation between EPO and ECP release after IgE-dependent stimulation. However, when EOSs with surface-IgA antibodies were incubated with anti-IgA MAb, both EPO and ECP were released. In contrast, incubation of EOSs with anti-IgG MAb induced mainly the release of ECP and not EPO. These results indicate that pharmacologically active mediators can be released by EOSs from allergic and nonallergic patients on immunoglobulin-dependent activation. The results also confirm the hypothesis of a selective release of the various granule proteins and raise the question of transduction signals delivered by the three Fc receptors (Fc epsilon R, FC alpha R, and FC gamma R) present on human EOSs.

Fast double antibody radioimmunoassay of human granulocyte myeloperoxidase and its application to plasma.

The haem enzyme myeloperoxidase (MPO) (EC 1.11.1.7) with a spectral A430/A280 ratio greater than 0.7 and a specific activity of 125 U/mg was purified from isolated human neutrophils. To obtain a radioimmunoassay (RIA) for this enzyme, a specific antiserum against human neutrophil MPO was raised in rabbits and used at an initial dilution of 1/10,000. MPO labelled with 125iodine by a technique of self-labelling in the presence of H2O2, had a specific activity of 24 mCi/mg. After incubation at room temperature (2 h) and separation by double antibody precipitation in the presence of polyethylene glycol, the sensitivity of the RIA was 21 ng/ml. The RIA showed good precision and accuracy with intra- and interassay coefficients of variation of less than 7% for MPO concentrations ranging from 100 to 800 ng/ml, and satisfactory recoveries of known amounts of exogenous MPO in plasma. For the measurement of MPO in blood, the best sampling technique was to collect blood into EDTA. Rapid centrifugation (within 20 min) was necessary for blood collected into heparin. Mean MPO values in normal individuals were 340 +/- 98 ng/ml in EDTA plasma (n = 152) and 332 +/- 82 ng/ml in heparinized plasma (n = 34). When MPO was measured 12-6 h after injury in critically ill patients high values (above 1000 ng/ml) were found in 6/15 patients with multiple injuries. In patients with sepsis (n = 22), MPO values were always above 1000 ng/ml.

Variations in protein expression related to human eosinophil heterogeneity.

In hypereosinophilic patients, eosinophil heterogeneity has been assessed mainly according to morphologic and biologic criteria. In order to investigate the molecular basis of such heterogeneity, biochemical analysis was performed on various eosinophil subpopulations fractionated on metrizamide gradients. Whole cell extracts from purified eosinophils disrupted with a nonionic (NP-40) detergent were successively analyzed by SDS-PAGE and two-dimensional electrophoresis (isoelectric focusing or nonequilibrium pH gradient electrophoresis in the first dimension). Hypodense eosinophils that sediment in the lightest density gradients (18 to 22% metrizamide solution) differed from other purified eosinophils (intermediate and normodense eosinophils respectively collected in 22 to 23% and 23 to 25% metrizamide solutions). Comparative analysis of protein patterns on both monodimensional and bidimensional electrophoresis showed that a basic protein of Mr 51 kDa, present on normodense or intermediate eosinophils, was poorly detected in the case of hypodense eosinophils. In contrast, two other proteins with apparent Mr of about 23 kDa and 41 kDa were exclusively or predominantly identified in these latter cell fractions. Immunochemical analysis with polyclonal antibodies against eosinophil basic proteins and enzymatic assays revealed that the 51-kDa polypeptide could be related to an eosinophil peroxidase-like molecule. In addition, the two proteins detected only in hypodense eosinophils might be related to proteins newly synthesized by in vivo activated eosinophils. Our results suggest that variations in protein expression might represent a good marker of in vivo activation.

Inhibition of human eosinophil chemotaxis and of the IgE-dependent stimulation of human blood platelets by cetirizine.

Cetirizine is a new anti-allergic compound with a potent, long-acting, and specific antihistaminic property. Strongly active in the therapy of urticaria and seasonal or perennial rhinitis, it has been shown to inhibit the in vivo eosinophil attraction at skin sites challenged with allergen in atopic patients. In the present work, we confirmed that, at a therapeutical concentration, this molecule had a potent inhibitory action in vitro on eosinophil chemotaxis induced either by N-formyl-Met-Leu-Phe or platelet-activating factor and also on the IgE-dependent stimulation of platelets. These observations appear in favour of a possible role for cetirizine in the modulation of inflammatory cell interactions in allergic processes.

Selectivity of mediators released by eosinophils.

The presence of receptors for IgE on eosinophils has drawn the attention on their direct participation in IgE-dependent hypersensitivity reactions. Surface IgE antibodies were detected on eosinophils from allergic patients. The addition of the specific allergen or anti-IgE antibodies to such purified eosinophils induced the release of eosinophil peroxidase, but not of eosinophil cationic protein. These findings associated with results obtained by using electron microscopy and immunogold staining of the various antibodies directed against the granule proteins allowed us to suggest a selectivity in the mediators released by eosinophils. In addition, preliminary results concerning the existence and the functional role of a receptor for IgA on eosinophils are reported, leading to the concept of a particular interaction of eosinophils with immunoglobulins present in the tissues and their participation in local immune responses.

Conjunctival provocation test as a model for the study of allergy and inflammation in humans.

The clinical response after allergen challenge and immunologic mechanisms leading to tissue inflammation have been extensively studied in the skin, nose and lung of allergic subjects. The present paper reviews personal studies aimed at evaluating clinical, cellular and humoral events after administration of specific allergen to the eye. Specific conjunctival provocation tests performed in grass-sensitive patients caused persisting inflammatory changes in conjunctival scrapings and tear fluid with a significant accumulation of different inflammatory cells depending on the time of observation (neutrophils, 20 min; eosinophils, 6 h; neutrophils, eosinophils and lymphocytes, 12-24 h after provocation). Increasing the dose of allergen resulted in a dose-dependent increase in the number of inflammatory cells recruited. When high doses of allergen were used, the challenge not only induced late-phase histological changes, but also clinical symptoms 6-10 h after provocation. Several mediators of allergic inflammation, such as histamine, C3a des-Arg, leukotrienes B4 and C4, were also present and could be measured in tears after allergen challenge. Our studies represent the first evidence in humans that a late phase of allergic reaction occurs in the eye. They also suggest that the conjunctival provocation test may represent a model for the study of cells and mediators involved in the pathophysiology of allergic inflammation as well as of its pharmacologic modulation.