PubMed Health⌕ Search

Biomedical subjects

E Colombo

Publications and source records attributed to E Colombo.

At least 19 recordsLinked to original sources
PubMed1992

Influence of thrombolysis on signal-averaged electrocardiogram and late arrhythmic events after acute myocardial infarction.

The influence of intravenous thrombolysis on both prevalence of ventricular late potentials and incidence of late arrhythmic events was evaluated in 174 consecutive patients surviving a first acute myocardial infarction; 106 patients (61%) received thrombolysis (group A) and 68 (34%) had conventional therapy (group B). In group A, 18 patients (17%) had late potentials compared with 23 (34%) in group B (p less than 0.05); mean left ventricular ejection fraction was not different (0.50 +/- 0.09 vs 0.50 +/- 0.10; p = not significant [NS]). Of 63 patients who underwent coronary arteriography because of postinfarction ischemia, 28 (44%) had a closed infarct-related artery; of these, 11 (39%) had late potentials compared with 3 of 35 (9%) with a patent artery (p less than 0.01). Mean left ventricular ejection fraction was not significantly different between the 2 groups (0.49 +/- 0.09 vs 0.53 +/- 0.09; p = NS). At a mean follow-up of 14 +/- 8 months, 8 of 161 patients (5%) had a late arrhythmic event; 6 of 8 (75%) with and 28 of 153 (18%) without events had late potentials (p less than 0.001). In group A, 4 of 99 patients (4%) had events compared with 4 of 62 (6%) in group B (p = NS, relative risk 1.6). Of 24 patients with anterior wall AMI and left ventricular dyskinesia, 6 events occurred. In this group of patients, a higher rate of events was observed (25%); 3 of 16 (19%) treated with thrombolysis had an event compared with 3 of 8 (37%) treated conventionally (p = NS, relative risk 2.6).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

Circadian variation of spectral indices of heart rate variability after myocardial infarction.

The circadian variations of spectral indices of heart rate variability were analyzed in 20 patients 4 weeks after a first and uncomplicated myocardial infarction (MI) and in 20 control subjects. R-R interval and variance showed a characteristic day-night pattern with a significant reduction of the latter parameter in patients after MI (10,967 +/- 1109 msec2 vs 16,860 +/- 2132 msec2). Control subjects were characterized by a predominance of low-frequency (approximately 0.1 Hz) component during the day and of high-frequency (approximately 0.25 Hz) component during the night, which reflected the expected 24-hour pattern of variation of sympatho-vagal balance. A 24-hour elevation (64 +/- 3 normalized units [nu] vs 56 +/- 2 nu; p less than 0.05) of the low-frequency component and a smaller (23 +/- 2 nu vs 32 +/- 2 nu; p less than 0.05) high-frequency component during the night differentiated patients after MI from subjects. The difference between the two groups was even more evident when the 24-hour sympatho-vagal balance was assessed with the low frequency/high frequency ratio. Thus spectral analysis of heart rate variability indicates that in patients after MI there is an alteration of neural control mechanisms as indicated by the presence of signs of sympathetic activation and by the attenuation of the nocturnal increase in vagal tone.

Aged↗
PubMed1992

Functional evaluation 10 days and 3 weeks after acute myocardial infarction: comparative significance and prognostic value.

Early functional evaluation after non-complicated acute myocardial infarction (AMI) is widely recommended because of its prognostic value in the short term. In fact it seems to have a prognostic value within 15-20 days of the AMI, but in this period the patient is particularly controlled and is often still hospitalized. To evaluate the real significance of an early functional evaluation within 10 days of the AMI (mean 8.6 days +/- 1.2) as compared to an identical functional evaluation performed at 3 weeks after AMI (mean 20.16 days +/- 5.38) 25 patients with uncomplicated myocardial infarction were studied. Significant statistical differences were found between the first (ET1) and second (ET2) functional evaluations: they concern the maximal heart rate reached (P less than 0.001), the maximal pressure-rate product (P less than 0.05), the percentage increment of heart rate (P less than 0.01) and the total work performed (P less than 0.001). Agreement between ET1 and ET2 was found in 19 cases; 12 patients showed markers of ischaemia both at ET1 and ET2, while seven were free from ischaemia at both times. In six cases a disagreement between ET1 and ET2 was found: in particular, three cases had ischaemic ET1 and nonischaemic ET2; the reverse was seen in the other three. During follow-up (mean 215.4 days +/- 85.5), the total number of new events (reinfarctions, angina or surgery) among the 25 patients was eight; none occurred within the first 30 days after the AMI.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

Myometrial invasion by endometrial carcinoma: assessment with plain and gadolinium-enhanced MR imaging.

A prospective study was designed to determine the sensitivity and specificity of nonenhanced T2-weighted and contrast material-enhanced T1-weighted magnetic resonance (MR) imaging in assessing the depth of myometrial invasion in patients with proved endometrial cancer. In 56 consecutive patients with clinically determined early-stage disease, findings of the two MR imaging techniques were compared with results of histologic examination of surgical specimens. Myometrial invasion was classified as absent (stage IA), superficial (stage IB), or deep (stage IC). In the assessment of each tumor stage, the sensitivity and specificity of contrast-enhanced T1-weighted MR imaging were higher than those of non-enhanced T2-weighted MR imaging. In determining the degree of myometrial tumor invasion, the overall sensitivity of enhanced T1-weighted MR imaging was 87.5%, whereas that of nonenhanced T2-weighted MR imaging was 71.4% (P less than .05). The use of contrast material may improve the ability to assess, with MR imaging, the depth of myometrial invasion by endometrial cancer.

Adult↗
PubMed1992

Regional flow responses to exercise.

Both neural and humoral systems participate in the control of blood flow to various organs. Exercise places the greatest demands on the circulation. At rest, in humans, skeletal muscle receives somewhere between 15% and 20% of cardiac output, while during maximal exercise, this percentage reaches a value of 80% to 90%. The active human muscles have a high-flow capacity that exceeds the capacity of the heart to pump blood. Measurements in single human muscle have indicated that blood flow may be inhomogenous, that is, probably depending on variations of the vasomotor tone of the muscle mediated by humoral and neural factors. Exercise raises cardiac output and coronary blood flow, which rise linearly with increases in heart rate. In normal young men, coronary blood flow averages 280 ml/min/100 g of the left ventricle and reaches as high as 390 ml/min during moderately severe exercise, requiring about 85% of maximal heart rate. In nonexercising organs, the blood flow decreases at about 20% to 40% of the resting values, being the net result of competing vasoconstrictor and vasodilator drives.

Animals↗
PubMed1992

[The electrocardiographic anomalies and 2D-echocardiographic findings during the recovery phase of the stress test in the postinfarct patient].

BACKGROUND: The appearance or the increase of repolarization abnormalities in the EKG during post exercise (ET) recovery phase (R) is considered a marker of ischemia. METHODS: In order to evaluate the real meaning of these changes we compared the EKG data with eventual modifications of left ventricular kinesis analyzed by 2D-ECHO. 10 male patients with previous myocardial infarction, mean age 50 +/- 4.8 y, underwent exercise testing on a treadmill (Bruce's protocol) and continuous 2D-ECHO observation from the end of exercise along the whole R. Patients were divided in two groups: Group A (6 patients) and Group B (4 patients), all free of symptoms. RESULTS: Group A showed ischemic EKG markers during exercise which increased during R; Group B showed ischemic EKG markers only during R. The 2D-ECHO showed in Group A an impairment of left ventricular kinesis at peak exercise without increase or extension during R (WMSI at rest 1.32; peak ET 1.60; R 1.60); in Group B the kinetic alterations appeared only in R (WMSI at rest 1.33, peak ET 1.42; R 1.80), strictly related to EKG markers. CONCLUSIONS: The data suggest : 1) that the increase of EKG abnormalities already present during exercise do not seem to imply more severe ischemia; 2) that EKG changes appearing during R are markers of ischemia which occur in the R.

Echocardiography↗
PubMed1992

Transfection of E. coli with lambda DNA by electroporation.

In the ambit of the B. subtilis genoma sequencing and mapping project, we have set up an electroporation method to transfect E. coli cells with lambda DNA. This methodology presents features that make it preferable to traditional in vitro packaging for some purposes. Here we will illustrate the experimental procedure and the possible applications.

Bacteriophage lambda↗
PubMed1991

Muscle fibre type and habitual snoring.

Although anatomical abnormalities of the upper airway have been recorded in some patients with obstructive sleep apnoea (OSA), a muscle tone dysregulation also seems to have an important role in this disorder. Since habitual snoring is the initial stage of OSA, the structural characteristics of upper airway muscles (medium pharyngeal constrictor muscle [MPCM]) from 13 men (9 non-snorers and 4 habitual snorers) were studied. MPCM fibre structure in non-snorers was broadly similar to that in normal limb muscles, with the exception that fibre diameters were smaller for all fibre types. Compared with limb muscles, MPCM had a smaller proportion of type IIb fibres and a higher proportion of types I and IIa fibres. MPCM in habitual snorers had an abnormal distribution of fibre types (low percentage of type I and type IIb fibres and high percentage of type IIa fibres) compared with non-snorers (p less than 0.001) and the type IIa fibres were hypertrophic. No myopathic or neurogenic changes were seen. Two possible hypotheses explain the abnormal distribution of fibre types in snorers. First, a constitutionally determined reduction of slow alpha-motor neurons induces an adaptive transformation of type IIb to type IIa fibres and a hypertrophy of type IIa fibres; or, second, motor neurons change their patterns of discharge and, hence, of activation, and modify fibre-type distribution of MPCM as an adaptation to the anatomical characteristic of upper airway and habitual snoring.

Adult↗
PubMed1989

[Etiopathogenesis and biodynamics of closed laryngo-tracheal injuries].

The blunt laryngotracheal trauma, once quite a rare phenomenon, has become quite relevant today, particularly because of the great increase in automotive traffic. It was, therefore, felt knowledge of the etiopathogenesis and biodynamics of this form of trauma is important for proper diagnosis and treatment. After having noted that the literature in this regard is generally incomplete and fragmentary, the authors felt it worth compiling the various etiopathogenesis and biodynamic factors involved; characteristics of blunt laryngotracheal trauma. Three basic elements of this form of trauma were studied. These are: trauma subject, trauma forces and impact plane. The biodynamic mechanisms responsible for the damage caused to the laryngotracheal skeleton and its soft parts have been analyzed. Finally, a case study was made including 99 cases drawn from international literature and 23 cases which had come under observation by the authors. The purpose of this analysis was to determine the frequency of various etiologies in relation to trauma type and site. The difficulties involved in drawing these simple data from the literature is underlined. This stems from the fact that often the various authors report overall data failing to give the etiology and site of individual cases. Traffic accidents have proved to be the cause of 80% of all such traumas and 90% of those with fracture, dislocation or separation of the laryngotracheal skeleton. The most serious lesions are to be seen in cases of frontal trauma. In the elastic cartilage of young people, the elastic snapback is of particular significance in the genesis of damage to the soft tissues. The most frequently encountered lesion is fracture of the thyroid cartilage alone while fracture of the cricoid alone is quite unusual. Fractures or detachment within the cricoid-tracheal area is quite common. In 85% of the cases cricoid cartilage involvement is associated with that of the tracheal cartilage. The authors assert that, due to a question of resistance, cricoid fracture traumas almost always involve the trachea while thyroid cartilage fractures act as a relief, letting off and absorbing the forces, thus preventing cricoid involvement. On the basis of these considerations the authors feel it fitting to classify the blunt laryngotracheal traumas into three groups according to topography: supraglottic laryngeal trauma with or without involvement of the glottis; subglottic laryngeal trauma, generally associated with the trachea and only rarely involving the glottic region; isolated trauma of the cervical trachea.

Accidents, Traffic↗
PubMed1989

[A comparative evaluation of tumor markers (TPA and CEA) in various malignant neoplasms at an advanced stage].

Radioimmunology was used to measure serum levels of CEA (carcinoembryonic antigen) in 108 patients with a variety of different advanced malignant neoplasms and in a control group of 60 healthy subjects. TPA proved more sensitive as a tumour marker than CEA, since increased TPA was found in 76% of the cancer cases compared to 42% for CEA. No significant increase in diagnostic sensitivity was obtained by using both markers rather than PTA alone.

Antigens, Neoplasm↗
PubMed1989

Motor effects of locally administered pinaverium bromide in the sigmoid tract of patients with irritable bowel syndrome.

The effects of pinaverium bromide, a non-absorbable antispasmodic agent, administered locally, on sigmoid-rectal motility was investigated in 20 patients with irritable bowel syndrome. The influence of either pinaverium (10 subjects) or placebo (10 subjects) on a neostigmine-induced increase of sigmoid pressure was assessed and compared by means of computerized electromanometry. The drug was found to counteract significantly the motor effects of neostigmine, thus appearing to be an effective compound for the treatment of functional disorders of the colon.

Adult↗
PubMed1988

Nizatidine and ranitidine in the short-term treatment of duodenal ulcer: a cooperative double-blind study of once-daily bedtime administration.

The aim of the present study was to assess the clinical efficacy and safety of a new H2-antagonist, nizatidine (N), administered as a single bedtime dose of 300 mg, compared with ranitidine (R) at the same dosage, in the short-term treatment of duodenal ulcer. One hundred forty one patients were included in the study: 70 were treated with N and 71 with R. During the study, three patients were withdrawn for unwanted effects not related to the treatment, and therefore, 69 patients per group were studied. After 4 wk of treatment, 58 patients treated with N (84.1%) and 55 in the group treated with R (77.5%), showed complete endoscopic ulcer healing (p greater than 0.5). The corresponding figure after 8 wk of therapy was 64 (94.2%) and 65 (94.2%) (p greater than 0.5). A similar effect on pain relief was observed: 42% of patients in both groups became asymptomatic after 4 wk. After 8 wk, the percentage rose to 84.2% in the group treated with N and 87.0% in the R group (p greater than 0.5). In both groups, only minor side effects occurred, not requiring drug discontinuation. These data show that nizatidine in a single bedtime dose of 300 mg is as effective and safe as ranitidine at the same dosage, and represents therefore a valid alternative to the usual H2-antagonists.

Adolescent↗