Search PubMed⌕ Search

Biomedical subjects

G Molinari

Publications and source records attributed to G Molinari.

At least 55 records · Page 3Linked to original sources
PubMed1992

Inhibition of motility of Pseudomonas aeruginosa and Proteus mirabilis by subinhibitory concentrations of azithromycin.

Exposure to subinhibitory concentrations (4-8 micrograms/ml) of azithromycin resulted in loss of motility in Proteus mirabilis strains and a significant reduction of motility in Pseudomonas aeruginosa strains. Examination revealed that the loss of motility was due to a total absence of flagella in Proteus mirabilis while the poor motility observed in Pseudomonas aeruginosa was due to absence of flagella in the majority of the population. Since motility may be considered a pathogenicity trait in the two species, these results confirm the unusual ability of azithromycin to reduce the expression of virulence factors in gram-negative pathogens.

Azithromycin↗
PubMed1992

[Magnetic resonance tomography compared to computed tomography in the intracardiac spread of hepatocarcinoma].

A cirrhotic patient with inferior cava and right atrium-ventricular invasion by hepatic tumor was studied with transthoracic echocardiography (TTE), computerized tomography (CT) before and after contrast agent bolus iv, ECG-gated magnetic resonance imaging (MRI). Obesity obstacled abdominal echotomographic study; esophageal varices were relative contraindication to transesophageal echocardiography (TEE). The resolutive diagnosis was possible thanks to MRI which documented the spatial continuity among hepatic tumor, intracaval neoplastic thrombus and intracardiac mass. TTE can be considered the first step in case of suspected cardiac masses, but it is sometimes limited by the thorax conformation and not always discriminant. TEE is semi-invasive with important contraindications. CT is limited by the only axial or para-axial scans with low quality reconstructions, worsened in these cases by respiratory and cardiac movements. MRI can be considered the second step in the imaging of cardiac masses, immediately and directly after the echocardiographic techniques.

Carcinoma, Hepatocellular↗
PubMed1992

[The angiographic evaluation of elastic recoil after coronary angioplasty].

Coronary angioplasty is an effective recanalization technique, but is plagued by a high restenosis rate. One of the major effects of balloon dilatation is the stretching of the vessel wall and the subsequent elastic recoil. Although a well known phenomenon, few data have been published on the evaluation of elastic recoil after coronary angioplasty. The purpose of this study was to quantify the acute and short-term elastic recoil after coronary dilatation. Thirty-six patients underwent coronary angioplasty. A digital end-diastolic acquisition of the coronary artery was performed before, immediately after, at 15 min and at 20 hours after dilatation. Elastic recoil was defined as the difference between the diameter of the inflated balloon and the diameter of the vessel after dilatation. It was quantified by a semi-automatic computer-assisted program. Our data show a high elastic recoil immediately after dilatation, equal to 27.9% (p < 0.0001), which continues for the next 20 hours to a final value of 34.1%. No difference was found in the amount of elastic recoil depending on the coronary artery involved, length, severity and eccentricity of the stenosis, time and pressure used during balloon inflation. Elastic recoil was more pronounced (p = 0.002) using balloons with a balloon diameter/vessel diameter ratio > 1.

Angioplasty, Balloon, Coronary↗
PubMed1991

Synergistic antibacterial interaction of cefotaxime and desacetylcefotaxime.

Cefotaxime (CTX) is metabolized in desacetylcefotaxime (dCTX), a less potent compound which shows, however, a higher stability against selected beta-lactamases produced by Gram-negative organisms. The aim of this study was to verify if the antimicrobial activity of CTX against 260 clinical aerobic and anaerobic pathogens isolated in our institution was enhanced by its metabolic derivative dCTX. The combination of CTX and dCTX, assessed by checkerboard titration, was completely or partially synergistic towards 61% of the 220 aerobic organisms tested and against 68% of the 40 Bacteroides strains analyzed. In addition we have investigated, by the time-kill method, the in-vitro interactions against 50 aerobic strains of CTX and dCTX alone and in combination with netilmicin, a drug often employed in severe infections in combination with beta-lactam agents in order to provide effective killing of resistant nosocomial pathogens. Time-kill studies indicated that 36% of the aerobic nosocomial strains were synergistically inhibited by the combination of CTX/dCTX with netilmicin. These results indicate that dCTX makes an important contribution to the clinical efficacy of CTX.

Bacteria↗
PubMed1991

[Intraluminal ultrasound echotomography: a new method in the study of arterial angioplasty. Evaluation of a case].

Intravascular ultrasound angioscopy allows to better define the structure of arterial wall and the effect of angioplasty. We report the case of a patient previously treated by coronary angioplasty, who underwent peripheral angioplasty for a stenosis of the left iliac artery. Intravascular ultrasound imaging performed before and after balloon dilatation clearly identified the plain of dissection and the partial resolution of the stenosis in a better way compared to digital angiography.

Angiography↗
PubMed1991

[The role of directional atherectomy in the study of postangioplasty restenosis].

Restenosis is the major limit of arterial recanalization devices. Directional atherectomy has allowed for the first to remove atheroma samples by a percutaneous approach. A group of patients affected by superficial femoral artery disease who underwent directional atherectomy were studied. The patients were treated for primitive stenosis, restenosis after balloon angioplasty and thermal laser angioplasty. Intimal hyperplasia was the distinctive feature of restenosis and the cells were identified by immunohistochemistry and transmission electron microscopy as smooth muscle cells in an active synthetic phenotype. No differences were found in the restenosis process after balloon angioplasty and laser thermal angioplasty. Directional atherectomy is a useful tool to ameliorate our knowledge in the restenosis process after invasive procedure of recanalization.

Aged↗
PubMed1990

Post-antibiotic effect of azithromycin on respiratory tract pathogens.

Azithromycin is a new azalide antibiotic with structural modifications that confer to the molecule acid stability, extension of antibacterial spectrum that includes important Gram-negative pathogens, long elimination half-life, and tendency to concentrate into various tissues where it persists for extended periods of time. The existence and length of a post-antibiotic effect (PAE), an important parameter for the characterization of new antibiotic molecules, has not yet been evaluated for this agent. In this study the PAE of azithromycin was assessed against representative respiratory pathogens included in the in vitro antimicrobial activity of the drug. The results obtained indicate that azithromycin produce a significant PAE on all Gram-positive and Gram-negative bacteria tested, resulting in an average value of 3.5 h for both S. pyogenes and S. pneumoniae, 3 h for B. catarrhalis and H. influenzae, and 2 h for Klebsiella spp. These findings support previous reports underlining the remarkable in vitro activity of azithromycin against H. influenzae, a pathogen poorly susceptible to the classical macrolides. Furthermore, the present demonstration of the existence of a long PAE of azithromycin against other Gram-positive and Gram-negative bacteria extends the pharmacokinetic advantages of the drug and strongly supports the application of this azalide in the therapy of respiratory infections.

Azithromycin↗
PubMed1990

[Electromyographic and computerized magnetic gnathokinesiographic studies of normal subjects].

The authors used electromyographic and computerised magnetic gnathokinesiographic equipment to examine habitual mastication and electromyographic activity of the masseter and anterior temporal muscles in two subjects with complete dentition, physiological functional occlusion and with no history or clinical records of cranio-mandibular disorders (CMD). The results obtained show the presence of common models of masticatory movement and electromyographic activity which conform to previously published data.

Dental Equipment↗
PubMed1990

[Electromyography and computerized magnetic gnathokinesiography in the diagnosis and therapy of craniomandibular disorders].

The paper describes the material and methods used to examine two subjects with cranio-mandibular disorders (CMD), one of a predominantly articular type and the other of a prevalently muscular type. Both patients presented significant and specific alterations of masticatory movement and electromyographic activity before treatment, and this enabled a differential diagnosis between the articular and muscular forms of CMD to be made. On the contrary, at the end of definitive occlusal treatment, kinesiographic and electromyographic parameters in the two subjects were normal and physiological, thus confirming the resolution of clinical symptoms.

Dental Equipment↗
PubMed1990

[Effects of magnesium pidolate on cardiovascular hemodynamics].

Aim of this study is to define the hemodynamic effects of magnesium (Mg) in patients with ischemic heart disease. Thus, the effects of 1 g of Mg pidolate injected over 3 min iv were evaluated in 10 patients by analysis of pressure data from a micromanometer catheter in the left ventricle and of volume data derived from Doppler and 2-dimensional echocardiography. Recordings were made before and immediately after the injection, at 3, 5, and 8 min. At 5 min, Mg induced a significant reduction in left ventricular peak systolic pressure (from 132.4 +/- 19.4 to 122.7 +/- 17.5 mmHg, p = 0.015, with early filling notably augmented (E wave of Doppler curve; from 39.4 +/- 8.5 to 43.9 +/- 9.7 cm/s, p = 0.013) and a slight increase in cardiac output (from 6.23 +/- 1.4 to 6.9 +/- 1.7 l/min, p = 0.092). Heart rate increased (from 75.9 +/- 9.6 to 78.13 +/- 8.4 b/min, p = 0.062) and the constant of isovolumetric pressure decay decreased (from 48.9 +/- 13.2 to 45.7 +/- 14.9 ms, p = 0.065), probably as a final effect of aortic pressure reduction. The diastolic pressure-volume relationship was insignificantly displaced downward (p = 0.11) and to the right (p = 0.62). In conclusion, Mg unloads the ischemic left ventricle through a reduction of systemic aortic pressure, with a secondary increase in early filling; this increase may derive from a rise in the atrioventricular diastolic gradient, subsequent to an improvement in ventricular emptying. Active relaxation is improved, and passive diastolic properties are not affected, in spite of the reported calcium-antagonist action of the drug.

Adult↗
PubMed1989

Dactimicin, a new aminoglycoside: in vitro activity, post-antibiotic effect and interaction with other antibiotics.

The in vitro activity of the new aminoglycoside dactimicin in comparison to amikacin was tested alone and in combination with piperacillin, mezlocillin and ceftazidime against freshly isolated clinical pathogens. Dactimicin was more active than amikacin against Enterobacter cloacae, Providencia rettgeri and Salmonella spp., and less active than amikacin against Escherichia coli, Pseudomonas aeruginosa and Acinetobacter anitratus. Using the checkerboard technique, the combination of either dactimicin or amikacin with the other drugs was shown to result in synergistic interaction against most of the 23 strains tested. Dactimicin-ceftazidime and amikacin-ceftazidime were the most effective combinations, demonstrating synergism against 91% and 95% of the isolates respectively. Antagonism was not encountered. Using the time-kill method, synergism was seen in most cases, indifference rarely being seen; antagonism was not observed. Dactimicin induced a post-antibiotic effect which ranged from 1 h for Enterobacter cloacae to 2.4 h for Escherichia coli. An average post-antibiotic effect of 0.6 h was also seen when dactimicin was combined with piperacillin, mezlocillin and ceftazidime. The findings indicate that dactimicin compares favorably in vitro with amikacin and suggest that clinical trials with this drug alone or in combination are warranted.

Acinetobacter↗
PubMed1989

In-vitro activity of meropenem against clinical isolates in a multicentre study in Italy.

A multicentre in-vitro study was undertaken to evaluate the susceptibility of bacterial pathogens isolated in different Italian hospitals to meropenem. A total of 1399 aerobic and 452 anaerobic strains was analysed. Comparative agents were imipenem, cefotaxime, ceftazidime, ceftriaxone, piperacillin, ciprofloxacin, gentamicin, amikacin, plus vancomycin when appropriate. The MIC ranges (mg/l) of meropenem were: 0.015-2 for Klebsiella spp., Proteus spp., Morganella morganii and Providencia spp.; less than 0.008-1 for Escherichia coli; 0.016-32 for Serratia spp.; 0.03-2 for Enterobacter spp. and Citrobacter spp.; 0.03- greater than 128 for Acinetobacter anitratus; 0.03-32 for Pseudomonas spp.; less than 0.008-0.5 for Haemophilus spp. and Neisseria spp.; 0.015-64 for Staphylococcus spp.; 0.06- greater than 128 for Enterococcus spp.; less than 0.008-0.25 for Streptococcus spp.; 0.016-8 for Fusobacterium spp.; 0.03-8 for Bacteroides spp.; less than 0.06-0.5 for anaerobic Gram-positive cocci; 0.08-2 for Clostridium spp. Meropenem exhibited superior antibacterial activity against the aerobic and anaerobic strains tested when compared to the other beta-lactam drugs. The new carbapenem was as active as ciprofloxacin and more active than imipenem and the aminoglycosides against Enterobacteriaceae and Ps. aeruginosa. It was also more active than ciprofloxacin against most strains of Gram-positive cocci. Meropenem was slightly less potent than imipenem against staphylococci and enterococci, with the exception of oxacillin-susceptible Staph. aureus against which meropenem and imipenem exhibited similar antibacterial activity.

Aminoglycosides↗
PubMed1989

[In vitro enamel fluoridation using an ultraviolet laser].

28 samples of human enamel have been studied in order to measure fluoride absorption after treatment with ultraviolet radiations. Samples treated with topical application only presented limited fluoride absorption in enamel surface (up to 0.5 microns deep). The absorption rate was higher, using an U.V. lamp. In samples treated with "excimer" laser, fluoride absorption was much higher in the surface layer and occurred also deeper (3 microns).

Absorption↗