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M Raimondi

Publications and source records attributed to M Raimondi.

At least 19 recordsLinked to original sources
PubMed2004

Potential energy surface, bound states, and rotational inelastic cross sections of the He-CH4 system: a theoretical investigation.

We determined two potential energy surfaces (PES) for the He-CH(4) system by means of MP4 and Valence Bond (VB) calculations. The MP4 potential is similar to the one commonly adopted for this system [U. Buck, K. H. Kohl, A. Kolhase, M. Faubel, and U. Staemmler, Mol. Phys. 55, 1255 (1985)], while the VB PES is slightly more attractive. To evaluate the reliability of these potentials, we investigated the scattering properties by performing close coupling calculations, and concluded that: (i) the available experimental data do not permit the ranking among the PES considered; (ii) some theoretical predictions differ considerably from the experimental data, and these discrepancies cannot entirely be ascribed to the inaccuracy of the ab initio calculations; (iii) the scattering properties at low energy might discriminate between the MP4 and VB potentials.

Journal Article↗
PubMed2004

[Territorial emergency: physician or nurse?].

This study was conceived to assess a pattern of Italian prehospital critical care team, especially referring to the advanced life support (ALS) rescue team. Function and management of ALS rescue team and its relationship with other members of the emergency medical system (intra hospital physician, basic life support team, general practitioner) are analysed; stress is laidon the knowledge, the background and the complexity of the emergency procedures. The benefit of 2 major prehospital options of the ALS team, composed by 1 physician and 1 nurse staffing or by 2 trained nurse staffing, is discussed; the importance of educational programs for ambulance teams, a comparison of cost-effectiveness and the number of emergency teams availability is underlined. The authors, finally emphasize the advantages of a territorial coverage with an integrated system of ambulances staffed with specially trained rescuers or technicians, ambulances with rescuers and nurses, and ALS teams staffed with emergency physician and 1 nurse (integrated or not with ambulances with 2 trained nurses), being perfectly capable to face up any background in pre-hospital emergency medicine setting.

Emergency Medical Services↗
PubMed2002

Emergency system prospective performance evaluation for cardiac arrest in Lombardia, an Italian region.

BACKGROUND: The aim of this research is to evaluate quality of out-of-hospital medical services in our country, using performance indicators and a new computerised database. METHODS: (a) EXPERIMENTAL DESIGN: Data were collected prospectively in three emergency dispatch centres for 90 days. Follow-up was evaluated at 1 day and 1 month after the event. This paper presents data on the cardiac arrest cohort only. (b) SETTING: Three emergency dispatch centres in Lombardia. (c) PATIENTS: One hundred and seventy-eight patients in non-traumatic cardiac arrest were enrolled. (d) INTERVENTIONS: None. The study was observational only. RESULTS: Mean interval between phone call and arrival on scene was 8.5+/-3.5 min. BLS manoeuvres were carried out from bystanders only in 15% of the cohort; this was associated with significant mortality reduction (85.7 versus 95.8%, chi(2) P<0.05). One hundred and thirty-three patients (75%) received assistance from BLS crews while only 45 patients (25%) were assisted by ALS medical personel, with a significant mortality reduction (ALS deaths 86.7%, BLS deaths 97%). Total 24 h survival was 9% and survival at 1 month declined to 6.17%. CONCLUSIONS: Quality monitoring produces objective information on interventions and outcomes. Only with this information, is it possible to implement improvement programmes that are planned according to the data presented.

Aged↗
PubMed2000

Interaction of Ia and IIa group cations with the guanine site in cytosine-guanine nucleic acid base pair: an ab initio Hartree Fock study in the absence of basis set superposition error.

Structures and energetics of complexes between guanine...cytosine Watson Crick (GCWC) DNA base pair and various metal cations were investigated by an ab initio Hartree Fock (HF) study in the absence of basis set superposition error. Cations were allowed to interact with N7 and O6 sites of guanine. The BSSE free gradient geometry optimisation were performed in the framework of the SCF-MI (self consistent field for molecular interactions) theory. In particular, the structure of the complex with the mono and bivalent cations, like H+, Na+, K+, Mg++, Ca++ were analysed showing that the coordination to the N7 and O6 sites of the GCWC pair can generate non-WC hydrogen bonding patterns. The results demonstrate that the a priori elimination of the BSSE allows to study molecular clusters of biological interest by employing small basis sets.

Base Pair Mismatch↗
PubMed1998

Multicenter randomized clinical trial on high-dose epirubicin plus cis-platinum versus vinorelbine plus cis-platinum in advanced non small cell lung cancer.

BACKGROUND: High dose Epirubicin (HD-EPI) (>90 mg/m2) and Vinorelbine (VNR) demonstrated antitumor activity as single agent (about 20%) in the treatment of advanced NSCLC. This trial compares these two agents combined with cisplatin (CP). PATIENTS AND METHODS: From August 1992 to February 1996, 228 patients with locally advanced or metastatic NSCLC were randomized to receive either EPI 120 mg/m2 as i.v. bolus plus Cisplatin (CP) 60 mg/m2 on day 1 (regimen A) or VNR 25 mg/m2 as i.v. bolus on day 1 and 8 plus CP 60 mg/m2 on day 1 (regimen B). Both treatments were recycled every 21 days up to a maximum cumulative dose of EPI of 840 mg/m2 or 12 cycles. Eligible patients were 212 and 198 patients were evaluable for objective response (95 in arm A and 103 in arm B). The main characteristics of eligible patients were: male/female 179/33; median age 61 (42-72); median Karnofsky PS 80 (70-100); stage IIIA 12%, stage IIIB 40%, stage IV 41%, recurrence 7%; histotype: epidermoid 48%, adenoca 36%, others 16%. RESULTS: The following response rates were observed in regimens A and B, respectively; CR, 1 and 2%, PR, 32 and 25% (P = 0.4567). Median CR + PR duration was 9 and 8 months, respectively. Median survival was 10.5 and 9.6 months, respectively. Grade III-IV leucopenia occurred in 38 and 21% in arm A and arm B, respectively(P = 0.01), thrombocytopenia in 6 and 0% (P = 0.02), anemia in 8 and 7% (n.s.). Non-hematological toxicity was moderate and the only difference between the treatments was alopecia (88 vs. 33% in arm A and B, respectively). Supraventricular arrhythmia occurred in three patients on regimen A; a >15% LVEF absolute decrease was observed in 9 (22.5%) and three (14%) patients on arm A and arm B, respectively (n.s.). No congestive heart failure was observed. CONCLUSION: HD-EPI+CP and VNR+CP are both active combinations in advanced NSCLC with a similar response rate, response duration and survival but regimen A was significantly more toxic (myelosuppression and alopecia).

Adult↗
PubMed1998

Wear of polyethylene cups in total hip arthroplasty: a parametric mathematical model.

This paper presents a parametric mathematical model of the head-cup wear coupling in total hip arthroplasty (THA). The model evaluates the dependence of acetabular volumetric wear upon the characteristic parameters of patient and hip prosthesis. Archard's law is assumed to calculate the wear coupling behaviour. The wear factor is taken from pin-on-disc wear tests as a function of materials and finishing of the articular joint. The forces acting on the hip joint are taken from experimental data found in the literature whilst the load distribution is calculated under the hypotheses of perfectly rigid ideal wear coupling. The sliding distance is obtained by combining the three elementary displacements -- due to rotations around the three axes -- at the generic bearing surface location. The simulations show that the polymeric wear volume per step cycle decreases ranging from fast walking speeds to low running speeds, it increases linearly with patient body weight and with femoral head diameter, it decreases slightly for positive variations of the socket inclination angle and it increases exponentially with femoral head roughness. The volumetric wear rate per year calculated for a standard reference patient is 5.8 mm3. The relevant iso-wear maps show a marginal pattern with the maximum located near the cup superior borderline. At the instant of peak load, the iso-stress maps show a paracentral pattern with the maximum superior to the cup polar point, and the iso-sliding distance maps show a marginal pattern with two maxima located near the cup's superior and inferior borderlines.

Acetabulum↗
PubMed1998

Cisplatin-vindesine-mitomycin (MVP) vs cisplatin-ifosfamide-vinorelbine (PIN) vs carboplatin-vinorelbine (CaN) in patients with advanced non-small-cell lung cancer (NSCLC): a FONICAP randomized phase II study. Italian Lung Cancer Task Force (FONICAP).

In the present multicentre randomized phase II trial, the activity and toxicity of three platinum-based combination regimens for the treatment of advanced non-small-cell lung cancer (NSCLC) were evaluated. The three regimens were: MVP (mitomycin-C 6 mg m(-2) on day 1, vindesine 3 mg m(-2) on days 1 and 15, and cisplatin 80 mg m(-2) on day 1 every 28 days), PIN (cisplatin 80 mg m(-2) day 1, ifosfamide 3 g m(-2) day 1 and vinorelbine 25 mg m(-2) day 1 and 8 every 21 days) and CaN (carboplatin 350 mg m(-2) day 1 and vinorelbine 25 mg m(-2) days 1 and 8 every 28 days). A total of 140 chemotherapy-naive patients entered the study; 49 patients were treated with MVP, 48 with PIN and 43 with CaN. Sixty-seven per cent of the patients had stage IV disease. Response rates, calculated on an 'intention to treat' basis, were as follows: MVP, 14.3% (95% CI 5.94-27.2%); PIN, 16.7% (95% CI 7.4-30.2%); and CaN, 14% (95% CI 5.3-27.9%). The overall median survivals were 256, 269 and 243 days for patients treated with MVP, PIN and CaN respectively. Myelosuppression was the most frequent toxicity: grade 3-4 leucopenia was observed in 14.3%, 25% and 18.6% of patients treated with MVP, PIN and CaN respectively. This multicentre phase II randomized trial shows that MVP, PIN and CaN can be administered on an outpatient basis with acceptable toxicities. Unfortunately, the three regimens showed an activity significantly lower than that reported in previous single-institution phase II trials.

Adult↗
PubMed1998

Human cell membrane oxidative damage induced by single and fractionated doses of ionizing radiation: a fluorescence spectroscopy study.

PURPOSE: To investigate the production and repair of lipid oxidative damage in two human cell lines exposed to acute and fractionated dose of ionizing radiation. Radiation dose was in the range from 0.1 to 44 Gy. MATERIALS AND METHODS: K562 and HL60 human cell lines have been used, 24 and 96 h after seeding. Membrane lipid oxidative damage has been detected by the measurement of the fluorescence decay of 1,6-diphenyl-1,3,5-hexatriene (DPH), its polarization value and the conjugated dienes concentration. The modification of DPH decay has been previously reported to be directly related to the lipid hydroperoxide concentration. RESULTS: A modification of the DPH decay has been observed as a linear function of the logarithm of the radiation dose and only when the irradiation was performed in the presence of oxygen. The amount of the damage is related to the time after the cell medium change. By exposing the cells to fractionated radiation doses for several days (10 cGy day(-1)), the oxidative damage has been found to be cumulative. After a single acute dose, evidence of repair of the lipid oxidative damage was not obtained. CONCLUSIONS: Following a previously developed method, the membrane damage was attributed to the production of hydroperoxide residues in the lipid acyl chains with the consequence of water penetration into the external portion of the bilayer, from the aqueous environment to the position of hydroperoxides. This damage is not repaired. The results obtained by measuring the DPH fluorescence decay have been compared with those obtained using other current optical and biochemical methods. None of these techniques could detect membrane oxidative damage at doses < 10 Gy. Finally, the different sensitivity of 'young' and 'old' cells to the oxidative damage can be related to different cholesterol concentrations.

Cell Membrane↗
PubMed1997

[Postpartum myoglobin blood monitoring in newborns. Correlations with renal function in the first 48 hours of life].

BACKGROUND: Myoglobin is a muscular tissue protein, and it is a very early damage index. As the newborn "thin mass" is less than that of the adult and knowing the renal dynamics of this protein clearance, the authors have analyzed the correlation between myoglobinemia and transitory renal failure, which is frequently present in newborns with fetal distress. METHODS: We examined a random population of 56 newborns (33 eutocic deliveries 14 caeserotomy, 9 various degrees of fetal distress) to which, after having had the parents' informed consent, the microsamples pattern was fixed at 0, 6, 12, 24, 48 hours from birth at the same time of ordinary exams to gauge: myoglobin with nephelometric method, CPK, creatininemia, azotemia and transaminase. The same exams were camed out on the mother at the beginning of labor and after delivery. RESULTS: We found that the placenta is not permeable to mother myoglobin, at the sixth hour from birth we have the highest value, while CPK is lower to increase, myoglobinemia associated with myoglobin variations. CONCLUSIONS: Myoglobinemia might be monitored to prevent distressed newborns from transitory renal tubular defect, justifying forced diuresis and urinary alkalosis.

Humans↗
PubMed1995

Cholesterol protects the phospholipid bilayer from oxidative damage.

The measurement of fluorescence lifetime distribution of 1,6-diphenyl-1,3,5-hexatriene is used for the detection of oxidative damage produced in phospholipid membranes by ionizing radiation. The recently developed method is based on the linear relationship between the width of the probe lifetime distribution and the logarithm of the dose. The molecular origin of the damage resides in the production of hydroperoxide residues at the level of acyl chains double bonds. A chemiluminescence assay was used to quantitate the amount of produced hydroperoxides. Consequences of the produced damages include an increased disorder in the upper portion of the bilayer, accompanied by the penetration of water molecules. In the presence of the physiological concentration of cholesterol in phopholipid bilayers, the amount of hydroperoxides produced by ionizing radiation is dramatically reduced. The packing effect of cholesterol in phopholipid bilayers is well recognized, as well as its influence on the reduction of water concentration in the bilayer. The dramatic reduction of hydroperoxides concentration observed when irradiation is performed in the presence of cholesterol probably originates from a steric hindrance to the radical chain reaction through the unsaturated lipids due to the presence of cholesterol.

Cholesterol↗
PubMed1995

Abrupt modifications of phospholipid bilayer properties at critical cholesterol concentrations.

The fluorescence generalized polarization (GP) of 2-dimethylamino-6-lauroylnaphthalene (Laurdan) reveals different effects of cholesterol on the phase behavior of phospholipid bilayers. Phospholipid vesicles composed of gel, liquid-crystalline, and coexisting domains of the two phases have been studied at temperatures from 1 to 65 degrees C, without cholesterol and with cholesterol concentrations of 3-50 mol %. Laurdan GP measurements show the general effect of cholesterol of increasing the molecular dynamics of the gel and of decreasing the molecular dynamics of the liquid-crystalline phase. In the liquid-crystalline phase, the increased order yields Laurdan GP values close to those obtained in the gel phase. At cholesterol concentrations > 15 mol % a phase transition cannot be detected. Using the wavelength dependence of the excitation and emission GP spectra we determine that differences between the two phospholipid phases cannot be detected. In particular, in vesicles composed of coexisting gel and liquid-crystalline phases the GP wavelength dependence characteristic of coexisting domains cannot be observed at cholesterol concentrations > or = 15 mol %. Cholesterol causes the decrease in both the polarity and the dipolar relaxation effects on the neighborhood of the fluorescent naphthalene moiety of Laurdan. Probably because of a cholesterol-induced increase in the bilayer packing, these effects do not occur continuously with the increase of cholesterol concentration in the bilayer. Cholesterol concentrations inducing higher Laurdan GP values have been determined at about 5, 10, 15, 30, and 45 mol % with respect to phospholipids. We propose that the formation of ordered molecular microdomains at critical cholesterol concentrations can explain the occurrence of the observed discontinuities.

2-Naphthylamine↗
PubMed1994

Evidence for an increase in water concentration in bilayers after oxidative damage of phospholipids induced by ionizing radiation.

The two membrane fluorescent probes 2-dimethyl-amino-6-lauroyl-naphthalene (Laurdan) and 2-dimethylamino-6-propionyl-naphthalene (Prodan) have been used to study the molecular basis of the damage induced in phospholipid membranes by ionizing radiation. Laurdan and Prodan display a spectral sensitivity to the polarity of their environment, showing a red shift of both excitation and emission spectra with increase of the polarity of their environment. Owing to their chemical differences, the two probes are anchored in the membrane with different strengths. In aqueous environments Laurdan is not fluorescent while Prodan shows appreciable fluorescence. Laurdan and Prodan show an opposite response to oxidative damage produced in phospholipid bilayers by ionizing radiation. The results support the model recently developed of water penetration in the bilayer as a consequence of oxidative damage.

Lipid Bilayers↗
PubMed1993

Absence of lipid gel-phase domains in seven mammalian cell lines and in four primary cell types.

Fluorescence properties of 6-lauroyl-2-dimethylaminonaphthalene (Laurdan) are used to explore gel and liquid-crystalline phase domains coexistence in membranes of various cell types and in erythrocyte ghosts. Experiments and simulations were performed using liposomes composed of equimolar gel and liquid-crystalline phases in the absence and in the presence of 30 mol% cholesterol. In this model system two distinct coexisting phases can be easily recognized in the absence of cholesterol. When cholesterol is added to this phospholipid mixture, Laurdan parameters characteristic of the gel and of the liquid-crystalline phase are no longer resolvable. Coexisting domains of gel and liquid-crystalline phase were not detected in any of the examined cell membranes as judged by Laurdan excitation and emission Generalized Polarization (GP) spectra. Both in liposomes and in cell membranes, the behaviour of GP values as a function of excitation and emission wavelength corresponds to a homogeneous liquid-crystalline phase, despite the absolute GP values being relatively high, closer to the values observed in gel phase phospholipids. The presence of cholesterol appears to be the major cause for the homogeneity of phospholipids' dynamical properties in natural membranes, properties that appear close to the liquid-ordered phase state, defined to describe model systems with cholesterol concentration > or = 30 mol%.

2-Naphthylamine↗
PubMed1992

[Isolated postoperative myoglobinuria as the only sign of malignant hyperthermia. Value of spinal anesthesia with bupivacaine in a posterior surgical intervention].

The Authors report a case of biopsy-proven malignant hyperthermia in a pediatric patient who underwent general anesthesia with halothane and succinylcholine for foot surgery, in whom the presenting symptom was isolated postoperative myoglobinuria. The above syndrome, in the absence of a positive family history, may present itself with a set of minor and atypical symptoms, thus being often underestimate. The need for further investigating all the cases of postoperative myoglobinuria is stressed by the Authors, which also consider muscular biopsy for inclusion among routine investigations. In the case reported here, six months later, a new surgical operation was done safely with spinal anesthesia using hyperbaric bupivacaine.

Anesthesia, Spinal↗