Search PubMed⌕ Search

Biomedical subjects

A Magrini

Publications and source records attributed to A Magrini.

At least 55 records · Page 3Linked to original sources
PubMed1995

Effects of ursodeoxycholic acid on serum liver enzymes in patients with hepatitis C virus-related chronic liver disease.

OBJECTIVE: To study the effect of ursodeoxycholic acid (UDCA) on serum liver enzyme levels [alanine aminotransferase (ALT) and gamma-glutamyl transferase (GGT)] in 101 patients with hepatitis C virus-related chronic liver disease. METHODS: Forty-nine patients were assigned to receive UDCA (450 mg/day) over a period of 6 months and 52 to receive no treatment. RESULTS: In the UDCA group, serum ALT and GGT levels significantly improved. ALT values decreased from pre-treatment levels of 157.0 +/- 62.6 IU/l to 82.5 +/- 46.4 IU/l (P < 0.05), and GGT fell from 141.3 +/- 86.2 IU/l to 66.0 +/- 49.5 IU/l (P < 0.001). No significant change occurred in the mean ALT and GGT levels in the control group. CONCLUSION: Although our encouraging preliminary results must be validated by double-blind histological trials, UDCA may be an alternative treatment for patients who fail to respond to interferon therapy.

Adult↗
PubMed1995

Timing and course of leucocyte aggregation in myocardial infarction.

In order to evaluate the pathophysiological relevance and clinical implications of leukocyte rheology in myocardial ischaemia we measured the percentage of aggregated leukocytes in 43 subjects with acute substernal pain before diagnosis. The percentage of aggregated leukocytes was significantly higher in 16 patients with subsequent diagnosis of myocardial infarction with respect to 11 with angina and 16 with non ischaemic chest pain (4.75 +/- 0.88, 3.43 +/- 0.65 and 1.52 +/- 0.32 respectively p < 0.01). The percentage of aggregated leukocytes was also evaluated in another group of 46 patients hospitalized for myocardial infarction. Among these, aggregated leukocytes were significantly higher in those with residual ischaemia, with respect to those without residual ischaemia (7.4 +/- 1.1 vs 3.5 +/- 0.6, p < 0.01). In conclusion, leukocyte aggregation is precociously increased after myocardial ischaemia. It may be a marker of residual ischaemia in patients with myocardial infarction.

Aged↗
PubMed1994

Leukocyte aggregation in patients with a previous cerebral ischemic event.

BACKGROUND AND PURPOSE: The role of leukocyte aggregation in ischemic stroke is controversial. In this study we investigated this hemorheologic alteration in patients at risk for stroke. METHODS: Leukocyte aggregation was evaluated with the leukergy test in 61 patients with a recent cerebral ischemic event and in 61 control subjects. RESULTS: In patients leukocyte aggregation was significantly higher than in control subjects (3.8 +/- 3.4% versus 2.5 +/- 2.2%; P = .01). In control subjects, the presence of vascular risk factors was associated with values of aggregation similar to those observed in patients. CONCLUSIONS: These findings suggest an association between altered leukocyte aggregation and cerebrovascular disease. Further investigations are needed to evaluate whether this hemorheologic alteration can be considered a marker of increased risk for stroke.

Aged↗
PubMed1993

Serial determinations of leukocyte aggregation in patients with ischemic stroke.

The pattern of leukocyte aggregation and its possible relationship with the clinical outcome were evaluated in 35 untreated patients with acute cerebrovascular disease during each of the first three days of hospitalization. Although statistically significant differences were found when comparing patients and age and sex matched controls during any of the 3 days, a large overlapping of values was noted in each comparison. The overlapping was strongly reduced when the average 3-day value was compared. Similarly, when comparing subgroups of patients classified on the basis of their clinical status, the overlap of values observed during any of the 3 days dropped from 70% to 30% when considering the average 3-day levels of leukocyte aggregation. Furthermore, the level of correlation between leukocyte aggregation and size of cerebral infarction was better when considering the average 3-day value (p = .005) than the best single-day correlation (p = .01). These data suggest that the association between acute cerebrovascular ischemia and leukocyte rheology is better discovered when repeated evaluation of the latter are performed.

Age Factors↗
PubMed1993

Influence of acute and chronic smoking on leukocyte aggregation.

The aim of the present study was to evaluate whether alterations of leukocyte aggregation are present before the development of smoking-associated diseases. Leukocyte aggregation, studied by means of the leukergy test, was significantly higher in 24 healthy smokers as compared to 18 healthy non-smokers (mean + SE) 4.4 +/- 2.2 vs 1.5 +/- 1.3; P < 0.02. Intermediate values were found in ex-smokers. A significant increase was observed in smokers who underwent the acute smoking of three cigarettes in 20 minutes (mean +/- SE) 3.5 +/- 1.9 vs 7.5 +/- 2.6; P < 0.02. These data indicate that changes of leukocyte aggregation induced by smoking are present in healthy subjects before the development of clinically evident diseases associated with smoking.

Cell Aggregation↗
PubMed1990

Optimal branching of human arterial bifurcations.

The area ratio, defined as the combined cross-sectional areas of the daughter branches divided by that of the parent artery, is an important indicator of "expansion" or "narrowing" in an arterial tree. In 120 morphologically normal human arterial bifurcations, angiographically studied, we measured branch artery diameters at and away from the bifurcation point to obtain "beta" and "D" ratios, respectively. These results were compared with optimal curves. Area ratio D values showed better agreement than area ratio beta with theoretical curves; for area ratio D, the positive regression line showed the same trend as expected from theory (y = 1.26 + 0.153x); for area ratio beta, the regression line was negative, showing a trend opposite to theory (y = 0.962 - 0.191x). Area ratio beta showed a significant correlation coefficient (r = 0.194; P less than 0.05) associated with aging, while for area ratio D it was not the same (r = 0.023; P less than 0.05). A significant correlation coefficient was also found between both of the area ratios and total branching angle. The new area ratio D, reflecting the branching geometry nearer to the bifurcation, is more promising than area ratio beta in the evaluation of optimal arterial bifurcation.

Adolescent↗
PubMed1986

Quantitative evaluation of spleen haemodynamics from radiocolloidal dynamic scintigraphy.

Quantitative information on spleen perfusion may be obtained as a byproduct of liver studies using 99Tcm colloids, by means of model analysis of dynamic data collected with a large field-of-view computerized gamma camera for about 4 min after intravenous administration of the tracer. Spleen extraction efficiency, vascular transit time, and parameters related to spleen blood flow, splenic clearance and volume of distribution of the tracer were computed, the latter three being expressed in arbitrary units. Results in 14 normal subjects and 78 patients with liver cirrhosis show good agreement with known physiopathological data. Results in five splenectomised patients and one patient undergoing ligation of the splenic artery provided further confirmation of the physiopathological meaning of the estimated parameters. Accuracy was found to be poor for spleens of small (normal) size, but was acceptable for enlarged spleens. Reproducibility of the results appears to be within 20%. It is concluded that this method, when associated with the study of liver function using a single 3-4 mCi dose of radiocolloids, may provide valuable additional information for routine assessment of splanchnic haemodynamics in patients with portal hypertension and splenomegaly.

Hemodynamics↗
PubMed1985

A new approach to non-invasive quantitative study of hepatic haemodynamics using radiocolloids in vivo.

A non-invasive radioisotopic method for the study of liver haemodynamics is described. Data collected by means of a computerised gamma camera for about 4 min after intravenous administration of 99Tcm human serum albumin colloids were analysed using a new mathematical model formulated on a physiopathological basis. Several quantities of possible clinical interest were determined, namely parameters related to liver blood flows, intrahepatic shunts, the intrahepatic space of distribution of the tracer, transit times and extraction efficiency. Results are not affected, within certain limits, by the shape of the radioactive bolus and, with the exception of extraction efficiency, they appear to be independent of the size of the radiocolloidal particle. The dose employed (3-4 mCi) is comparable with that used in liver scintigraphy. Results in 19 subjects with normal liver function, 45 patients with liver cirrhosis and 7 patients with focal liver lesions were in good agreement, from a quantitative viewpoint, with known physiopathological data, thus validating this method in comparison with other more traumatic and/or less practical techniques, which provide less complete information on liver haemodynamics. The method proposed appears to be sufficiently accurate, reproducible, safe and practical, and may thus be considered suitable for routine use in the assessment of functional aspects of liver perfusion for clinical purposes.

Cysts↗
PubMed1983

On the interpretation of the early part of the liver time-activity curve: double tracer experiment.

A double tracer experiment was performed in one normal subject and in one cirrhotic patient to better understand the tracer kinetics in the liver area during the first minute after injection. From a comparison of the time-activity curves obtained in each subject by subsequent iv administration of a nonextracted and an extracted (colloidal) tracer it was possible to distinguish the contribution due to the transport mechanism through intrahepatic and extrahepatic circulation and that due to reticuloendothelial extraction. Three main phases were identified on the curves and an attempt was made to interpret their significance. Results of the study may be of interest for the development of models which could possibly provide more reliable noninvasive quantitation of liver hemodynamics and reticuloendothelial function with the use of one or both types of tracer.

Hemodynamics↗
PubMed1980

A new automatically controlled electric TAH.

Cardiovascular regulatory mechanisms are implemented by means of a very complex control system involving neural, humoral, and mechanical agents. The state of the art in TAH today reveals that we have passed a stage where we can be satisfied with a 6 or 9 mo survival. Development and implementation of a versatile control theory must be another milestone before a TAH can really serve the prospective patient population requiring such a device. This study reveals the vital role and merits as well as the feasibility of incorporating such a control theory into the device.

Heart, Artificial↗
PubMed1979

Radioisotope X-ray fluorescence technique in the study of joint inflammation.

An X-ray fluorescence technique was employed to study the clearance rate from the knee joint of an intraarticularly injected stable tracer. Clearance curves, determined in two normal volunteers and in three patients with various articular diseases, were found to be of the monoexponential type in agreement with results obtained by authors employing radioactive tracers. Clearance half-time values in basal conditions were higher in the normal knee joint than in the inflamed knee joint. The effect of a corticosteroid suspension injected into the knee joint was also studied. Preliminary results obtained indicate that the X-ray fluorescence technique can be employed, with some advantages compared with the radiotracer technique, for quantitative determination of spontaneous or pharmacologically induced changes in joint inflammation.

Humans↗
PubMedDate not supplied

Enzyme polymorphisms, smoking, and human reproduction. A study of human placental alkaline phosphatase.

We investigated the possible effects of placental alkaline phosphatase (PLAP) genotype on the deleterious action of maternal smoke on intrauterine survival and birthweight. PLAP is a highly polymorphic enzyme with several alleles associated with different enzymatic activities. PLAP is produced by the embryo and is found in maternal blood, where it is responsible for the rise of serum alkaline phosphatase during pregnancy. Two hundred and fourteen Caucasian consecutive newborn infants delivered in the Maternity Department of the University of Rome La Sapienza Hospital were studied. Infants from smoking women 28 years or older show a strong decrease of both PLAP*1/*1 and *2/*2 homozygous types and a marked deviation from Hardy-Weinberg expectation, thus suggesting a different lethal effect of smoke depending on PLAP genotype and maternal age. In infants from smoking mothers there is a decrease of birthweight that is much less evident and statistically not significant in infants carrying the PLAP*1/*1 genotype as compared to other genotypes. The difference between PLAP genotypes concerning birthweight is more marked in women older than 28 years than in younger ones. This suggests that the effects of smoke on birthweight are also dependent on PLAP and maternal age.

Adult↗
PubMedDate not supplied

Leukocyte count and aggregation during the evolution of cerebral ischemic injury.

We evaluated leukocyte aggregation by means of the leukergy test and count in 26 patients with atherothrombotic stroke and in 10 patients with transient ischemic attacks. The evaluation was performed within 24 h from the onset of symptoms and then repeated on day 2, 4, 6 and 8. Data were compared with those of 10 healthy controls. Stroke patients were followed until day 30 when a clinical examination and brain computed tomography were performed to evaluate the extent and outcome of cerebral damage. Both leukocyte aggregation and count were significantly increased in stroke patients with respect to controls. While leukocyte count was not able to differentiate the severity of neurological impairment in stroke patients, leukocyte aggregation was significantly higher in major than in minor stroke patients on days 2 and 4 (p < 0.05). Moreover, while values of leukocyte count recorded at entry remained substantially stable in the following determinations in all groups, leukocyte aggregation showed a significant increase (p < 0.05) on day 4 with respect to all the other determinations in major stroke patients. These findings show that the extent and temporal profile of changes in leukocyte count and aggregation are different in patients with cerebrovascular disease and suggest an involvement of altered leukocyte rheology in the development of cerebral ischemic injury.

Aged↗
PubMedDate not supplied

Are thyroid dysfunctions related to stress or microwave exposure (900 MHz)?

In the last decade, numerous scientific evidence suggested possible adverse health effects from exposure to electromagnetic fields (EMF'S) and the use of mobile phones. According to some studies EMF induced changes of trans-membrane Ca++ flux may lead to altered metabolism and/or secretion of neurohormones including TSH, ACTH, GH, prolactin and melatonin. The aim of this research was to analyse the effects of mobile phone use on thyroid function and to evaluate the possible role of occupational stress. 2598 employees (1355 men and 1243 women) with different duties (vendors, operators and network technicians) were included in the study. Exposure to EMF'S, generated by mobile phones, was assessed both by submitting a questionnaire directly to the employees and acquiring data regarding conversation times. The workers were divided into three groups on the basis of their personal mobile phone use. Moreover, a group of 160 workers with TSH values below 0.4 UI/l was characterized. No statistically significant difference regarding TSH values below 0.4 UI/l was observed among workers with different duties but there was a greater prevalence of subjects with low SH values among 192 employees with more than 33 hrs./month conversation time; this difference was statistically significant (p<0.05). On the basis of our data, it is not possible to establish whether this result is determined by exposure to EMF'S from mobile phones of by the stress of using these instruments.

Adult↗
PubMedDate not supplied

[Nanotubes and fullerenes: an overview of the possible environmental and biological impact of bio-nanotechnologies].

BACKGROUND: Nanotechnology operates in a dimension that is invisible not only to the human eye but also to most highly sensitive instruments; this technology has made it possible to manufacture materials that have not existed in our environment before. In the medical sphere, many important applications in the diagnosis and treatment of diseases are foreseen. Up to now nanotechnology has evaded social, political and regulatory scrutiny concerning the safety of nano-particles in workplaces and in commercial products. OBJECTIVES: The present article reports the most important bio-medical applications of nanotechnology, followed by the results of research on the individual and environmental effects of nanomaterials and in particular of nanotubes, that are considered one of the most fascinating discoveries of the last millennium. METHODS: A report is given on the data presented at the 225th ACS National Meeting (March 23-27, 2003, New Orleans, LA), division of Industrial and Engineering Chemistry. RESULTS: Nanotubes and fullereness are recently discovered different forms of carbon-based materials which are widely applied in various technical fields. One of the main concerns regarding these structures is that they resemble asbestos fibers. CONCLUSIONS: Although preliminary studies suggest that these materials are not associated with any health risk, many researchers highlight the need to assess possible risks of such structures before they become ubiquitous in every aspect of life.

Biological Science Disciplines↗