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M Lombardi

Publications and source records attributed to M Lombardi.

At least 37 records · Page 2Linked to original sources
PubMed1999

Assessment of trigeminal small-fiber function: brain and reflex responses evoked by CO2-laser stimulation.

Laser pulses selectively excite mechano-thermal nociceptors and evoke brain potentials that may reveal small-fiber dysfunction. We applied CO2-laser pulses to the perioral and supraorbital regions and recorded the scalp laser-evoked potentials (LEPs) and reflex responses in the orbicularis oculi, masticatory, and neck muscles in 30 controls and 10 patients with facial sensory disturbances. Low-intensity pulses readily evoked scalp potentials consisting of a negative component with a latency of 165 ms followed by a positive component at 250 ms. In vertex recordings, the amplitude of LEPs exceeded 30 microV. Although only high-intensity pulses evoked reflex responses, some subjects showed--even to low-intensity pulses--an orbicularis oculi (blink-like) response that markedly contaminated the scalp recording. Scalp LEPs were abnormal in patients with hypalgesia and normal trigeminal reflexes and normal in patients with normal pain sensitivity and abnormal trigeminal reflexes. Possibly because of the high receptor density in this area and the short conduction distance, laser stimulation of the trigeminal territory yields low-threshold and large LEPs, which are useful for detecting dysfunction in peripheral and central pain pathways.

Adult↗
PubMed1999

Use of the mean transit time of an intravascular contrast agent as an exchange-insensitive index of myocardial perfusion.

A simple two-compartment model was used to study the effects of water exchange on the signal produced by an inversion recovery prepared rapid gradient-echo sequence during the first passage of a low dose of an intravascular contrast agent. Water exchange at intermediate rates of exchange (1-10 Hz) between the vascular and extravascular spaces caused the form of the signal changes during the first pass to be dependent on both the fractional sizes of the vascular and extravascular compartments and on the exchange rate. Unless the effects of exchange are minimized by using a very short inversion time, parameters such as the peak height and area under the curve will be affected by regional and/or pathological variations in the exchange rate and the size of the vascular fraction. The mean transit time (MTT) is, however, less affected by water exchange. Experimental first-pass data produced by intravascular low-dose injections of iron oxide particles were studied in five pigs at 0.5 T. The MTT as derived from the first-pass curves, without deconvolution with the arterial input function, was well correlated with the myocardial blood flow (MBF) as measured using radioactive microspheres (r = 0.70, n = 52, P < 0.01). Other first-pass parameters such as the peak height or area under the curve exhibited either a poorer, or no, correlation with the MBF. The data suggest that the MTT of the first pass of an intravascular contrast agent may be a robust, quantitative method for assessing myocardial blood flow in patients.

Animals↗
PubMed1999

Prevalence and clinical outcome associated with preexisting malnutrition in acute renal failure: a prospective cohort study.

Malnutrition is a frequent finding in hospitalized patients and is associated with an increased risk of subsequent in-hospital morbidity and mortality. Both prevalence and prognostic relevance of preexisting malnutrition in patients referred to nephrology wards for acute renal failure (ARF) are still unknown. This study tests the hypothesis that malnutrition is frequent in such clinical setting, and is associated with excess in-hospital morbidity and mortality. A prospective cohort of 309 patients admitted to a renal intermediate care unit during a 42-mo period with ARF diagnosis was studied. Patients with malnutrition were identified at admission by the Subjective Global Assessment of nutritional status method (SGA); nutritional status was also evaluated by anthropometric, biochemical, and immunologic parameters. Outcome measures included in-hospital mortality and morbidity, and use of health care resources. In-hospital mortality was 39% (120 of 309); renal replacement therapies (hemodialysis or continuous hemofiltration) were performed in 67% of patients (206 of 309); APACHE II score was 23.1+/-8.2 (range, 10 to 52). Severe malnutrition by SGA was found in 42% of patients with ARF; anthropometric, biochemical, and immunologic nutritional indexes were significantly reduced in this group compared with patients with normal nutritional status. Severely malnourished patients, as compared to patients with normal nutritional status, had significantly increased morbidity for sepsis (odds ratio [OR] 2.88; 95% confidence interval [CI], 1.53 to 5.42, P < 0.001), septic shock (OR 4.05; 95% CI, 1.46 to 11.28, P < 0.01), hemorrhage (OR 2.98; 95% CI, 1.45 to 6.13, P < 0.01), intestinal occlusion (OR 5.57; 95% CI, 1.57 to 19.74, P < 0.01), cardiac dysrhythmia (OR 2.29; 95% CI, 1.36 to 3.85, P < 0.01), cardiogenic shock (OR 4.39; 95% CI, 1.83 to 10.55, P < .001), and acute respiratory failure with mechanical ventilation need (OR 3.35; 95% CI, 3.35 to 8.74, P < 0.05). Hospital length of stay was significantly increased (P < 0.01), and the presence of severe malnutrition was associated with a significant increase of in-hospital mortality (OR 7.21; 95% CI, 4.08 to 12.73, P < 0.001). Preexisting malnutrition was a statistically significant, independent predictor of in-hospital mortality at multivariable logistic regression analysis both with comorbidities (OR 2.02; 95% CI, 1.50 to 2.71, P < 0.001), and with comorbidities and complications (OR 2.12; 95% CI, 1.61 to 2.89, P < 0.001). Malnutrition is highly prevalent among ARF patients and increases the likelihood of in-hospital death, complications, and use of health care resources.

Acute Kidney Injury↗
PubMed1998

Significance of myocardial ischemic electrocardiographic changes during dipyridamole stress echocardiography.

The aim of this study was to assess the diagnostic and prognostic value of the presence and characteristics of ischemic electrocardiographic (ECG) changes during dipyridamole stress echocardiography. The ECG response in 178 patients with echocardiographic evidence of myocardial ischemia during dipyridamole stress testing was analyzed. ECG changes occurred in 105 patients (59%). Patients with ECG changes had a higher incidence of echocardiographic signs of ischemia at a low dose than patients with an unchanged electrocardiogram (50% vs 23%; p = 0.0002). Three-vessel and/or left main coronary artery disease (CAD) was found in 41% of patients with and in 21% of patients without ECG changes (p = 0.029). During follow-up (33 +/- 19 months), 30 cardiac events occurred: 10 deaths, 6 infarctions, and 14 unstable anginas. Coronary revascularization was performed in 48 patients with and in 17 patients without ECG changes (p = 0.0022). The univariate predictors of cardiac events were: presence of ischemia in > or =4 ECG leads (p = 0.0004), echocardiographic evidence of ischemia at a low dose (p = 0.0062), ST-segment shift on precordial leads (p = 0.0094), family history of CAD (p = 0.0115), coexistence of > or =3 cardiovascular risk factors (p = 0.0156), ST-segment depression (p = 0.0172), and ECG changes during testing (p = 0.0335). At Cox analysis, occurrence of ischemia at a low dose (odds ratio 3.0; 95% confidence interval 1.3 to 6.8) and the presence of ischemia in > or =4 ECG leads (odds ratio 3.5; 95% confidence interval 1.3 to 9.3) had an independent prognostic importance. In conclusion, the presence and characteristics of ischemic ECG changes are associated with more extensive CAD and worse prognostic outlook than are echocardiographic changes alone during dipyridamole stress echocardiography.

Aged↗
PubMed1998

Activation of the Src/p21ras/Erk pathway by progesterone receptor via cross-talk with estrogen receptor.

The molecular mechanisms by which ovarian hormones stimulate growth of breast tumors are unclear. It has been reported previously that estrogens activate the signal-transducing Src/p21(ras)/Erk pathway in human breast cancer cells via an interaction of estrogen receptor (ER) with c-Src. We now show that progestins stimulate human breast cancer T47D cell proliferation and induce a similar rapid and transient activation of the pathway which, surprisingly, is blocked not only by anti-progestins but also by anti-estrogens. In Cos-7 cells transfected with the B isoform of progesterone receptor (PRB), progestin activation of the MAP kinase pathway depends on co-transfection of ER. A transcriptionally inactive PRB mutant also activates the signaling pathway, demonstrating that this activity is independent of transcriptional effects. PRB does not interact with c-Src but associates via the N-terminal 168 amino acids with ER. This association is required for the signaling pathway activation by progestins. We propose that ER transmits to the Src/p21(ras)/Erk pathway signals received from the agonist-activated PRB. These findings reveal a hitherto unrecognized cross-talk between ovarian hormones which could be crucial for their growth-promoting effects on cancer cells.

Animals↗
PubMed1998

Risk stratification by pharmacological stress echocardiography in a primary care cardiology centre. Experience in 1082 patients.

AIM: In this study we sought to determine the safety, feasibility and prognostic value of pharmacological stress echocardiography performed in a primary care cardiology centre, populated by unselected patients evaluated with the aid of limited financial and technological resources. METHODS AND RESULTS: The study population was 1082 patients undergoing pharmacological stress echocardiography with either dipyridamole (n=714) or dobutamine (n=368) for the evaluation of known or suspected coronary artery disease. The echocardiogram was positive in 284 (26%) patients. Two sustained ventricular tachycardias, reversible by antidote, occurred during stress testing. Limiting ischaemia-independent side effects occurred in 1.5% dipyridamole and in 2.4% dobutamine stress echocardiograms. During follow-up (33+/-18 months), 17 cardiac deaths and 27 non-fatal myocardial infarctions occurred. One hundred and twenty-seven patients underwent coronary revascularization, of whom 105 (37%) had a positive and 22 (3%) a negative stress testing result (P<0.0001). At Cox analysis, allowing for 14 clinical and stress-echo variables. the independent predictors of cardiac death were, in decreasing order, a positive stress testing result (Odds ratio [OR]=6.0), resting wall motion score index (OR=5.7), age greater than 65 years (OR=4.9), previous Q-wave myocardial infarction (OR=3.5), and hypercolesterolaemia (OR=2.7). The 4-year survival rate was 99.2% for patients with a negative and 89.8% for patients with a positive stress testing result (P=0.0000). When cardiac hard events (cardiac death and non-fatal myocardial infarction) were considered as end-points, the following variables were independently associated with prognosis: positive result of stress testing (OR=3.1), hypercolesterolaemia (OR=2.4), and resting wall motion score index (OR=2.7). The 4-year infarction-free survival rate was 97.0% for patients with a negative and 81.4% for patients with a positive stress testing result (P=0.0000). CONCLUSIONS: Pharmacological stress echocardiography with either dipyridamole or dobutamine was safe and feasible, providing an excellent tool for prognostic assessment of coronary artery disease in a primary care cardiology centre.

Aged↗
PubMed1997

Prognosis of myasthenia gravis: a retrospective study of 380 patients.

The 9139 follow-up records of 438 myasthenia gravis (MG) patients were reviewed. Excluding those patients who were diagnosed 5 or more years after symptom onset (n = 37) and those who experienced only oculomotor symptoms throughout follow-up (n = 21), there were 380 patients. A survival analysis approach was used to assess the influence of prognostic factors on the following endpoints: (a) stable complete remission, (b) complete remission of at least 6 months and (c) pharmacological remission of at least 6 months. Early diagnosis was associated with a better prognosis with respect to all endpoints. Thymectomy also improved the prognosis but only for those patients without thymoma. Later MG onset was associated with a higher tendency to achieve pharmacological remission.

Adult↗
PubMed1997

An independent software system for the analysis of dynamic MR images.

PURPOSE: A computer system for the manual, semi-automatic, and automatic analysis of dynamic MR images was to be developed on UNIX and personal computer platforms. The system was to offer an integrated and standardized way of performing both image processing and analysis that was independent of the MR unit used. MATERIAL AND METHODS: The system consists of modules that are easily adaptable to special needs. Data from MR units or other diagnostic imaging equipment in techniques such as CT, ultrasonography, or nuclear medicine can be processed through the ACR-NEMA/DICOM standard file formats. A full set of functions is available, among them cine-loop visual analysis, and generation of time-intensity curves. Parameters such as cross-correlation coefficients, area under the curve, peak/maximum intensity, wash-in and wash-out slopes, time to peak, and relative signal intensity/contrast enhancement can be calculated. Other parameters can be extracted by fitting functions like the gamma-variate function. Region-of-interest data and parametric values can easily be exported. RESULTS AND CONCLUSION: The system has been successfully tested in animal and patient examinations.

Algorithms↗
PubMed1997

[Liposarcoma of the spermatic cord. Clinical case].

Sarcomas are neoplasms originating from connective tissues of any anatomical region; the sarcoma of spermatic cord is a rare neoplasm with only little more than two hundred cases described in the literature. Rhabdomyosarcomas in childhood and leiomyosarcomas in adults are the most frequent histological types. Liposarcomas, fibrosarcomas and osteosarcomas are less frequent. The spermatic cord liposarcoma originates from the spermatic cord fatty tissue and therefore it consist of adipose cells, fibroblasts and myxomatosus cells; such neoplasms are usually very well differentiated. Diagnosis is suggested by the appearance of a progressively enlarging mass and by echotomography which shows a solid or liquid mass of the spermatic cord. Therapy consists of surgical intervention (orchifunicolectomy) which also allows a correct histological diagnosis. The case of a 56 year-old male who underwent left orchifunicolectomy for a sarcoma of spermatic cord occasionally discovered during surgical repair of a left groin hernia is reported. Six months after the intervention the patient is in good condition and there is no evidence of relapse.

Genital Neoplasms, Male↗
PubMed1997

Augmentation ileocystoplasty in a case of eosinophilic cystitis.

Eosinophilic cystitis (EC) is a rare form of bladder inflammation characterized by massive eosinophilic infiltration of the bladder wall. The most frequent signs and symptoms are pollakiuria, urgency, macroscopic haematuria and hypogastric pain: the involvement of the ureters may cause hydronephrosis and renal failure. Eosinophilia and eosinophiluria are present in 35% and in 50% of the cases respectively. EC may evolve towards sclerosis up to the anatomoclinical picture of small retracted bladder, which requires to be differentiated from tubercular cystitis, interstitial cystitis and cancer. Imaging techniques are not definitely diagnostic. Diagnosis can be reached only by biopsy with the microscopic demonstration of eosinofilic infiltration of the whole bladder wall in the early and acute stages, while fibrosis with poor cellularity predominates in the chronic stages. Etiology is unknown and the hypothesis of an allergic origin is unproved even though remissions or recoveries induced by steroidal therapy have been reported. Surgical therapy of EC, as in our observation, is absolutely required to correct urgency and incontinence and to prevent renal failure when the urinary upper tract has been primarily or secondarily involved.

Aged↗
PubMed1996

Residual myocardial perfusion in reversibly damaged myocardium by dipyridamole contrast echocardiography.

In patients with previous myocardial infarction and left ventricular asynergy, dipyridamole infusion may have the capacity to unmask myocardial viability through transient recovery of contractile function in asynergic segments. The purpose of this study was to assess simultaneous changes in myocardial perfusion and LV function--elicited by dipyridamole infusion--in infarcted, asynergic segments. The echo contrast agent Albunex was injected into the left coronary artery of 19 patients (17 males, age 49-70 years) with previous myocardial infarction and baseline left ventricular asynergy, both before and after dipyridamole infusion (up to 0.56 mg.kg-1, i.v.). Analysis was not possible in three patients due to inadequate image quality and in two due to weak contrast. There were no major adverse events, or changes in vital signs or demonstrated on the electrocardiogram. After dipyridamole, 7/14 patients, showed an improvement in regional function of asynergic segments ('responders'), whereas seven patients did not ('non-responders'). Among non-responders, five had a myocardial perfusion deficit corresponding to 41% of the total left ventricular area before dipyridamole and to 38% after dipyridamole. No baseline perfusion deficits were observed in the remaining two non-responders; one of these, however, developed transient asynergy and perfusion deficit after dipyridamole. Among responders, five showed a normal perfusion pattern, both before and after dipyridamole, while the remaining two showed a perfusion deficit which markedly decreased after dipyridamole (from 32% to 13% of total left ventricular area). Thus, residual contractile reserve of asynergic, infarcted ventricular segments appears to be associated with myocardial perfusion either preserved at baseline or recruitable by a coronary dilator stimulus.

Aged↗
PubMed1995

Breathing during sleep in myasthenia gravis.

The aim of this study was to assess breathing patterns during sleep in patients with generalized mild myasthenia gravis. Fourteen patients (13 F; 1M, age range 20-40 years) in a stable clinical and functional state underwent a sleep questionnaire, baseline respiratory function tests and standard nocturnal polysomnography. All of the patients had normal daytime blood-gas values, except one who showed mild hypoxemia. No patient complained of disturbed sleep; six patients reported snoring. In five patients nocturnal polysomnography showed the occurrence of short and infrequent central apneas mainly during REM sleep, together with a drop in HbSaO2 levels of more than 5% of the baseline wakefulness value. Our data indicate that, in patients with mild generalized MG in a stable functional state, breathing pattern instability during sleep is infrequent and, when it occurs, is mild and mainly related to REM sleep.

Adult↗