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Biomedical subjects

M Marconi

Publications and source records attributed to M Marconi.

At least 73 records · Page 4Linked to original sources
PubMed1991

A short plasma exchange protocol is effective in severe myasthenia gravis.

Plasma exchange has been reported to be a successful therapeutic procedure for the treatment of severely compromised myasthenic patients, but the optimal regimen in terms of costs or clinical benefit has not so far been determined. We have investigated the efficacy of a short plasmapheresis protocol of two exchanges 1 day apart in a series of 70 patients with severe forms of myasthenia gravis. Patients were evaluated before and 7 days after the first exchange. A positive outcome was observed in 70% of the plasma exchange cycles performed. Disease severity did not seem to be a negative prognostic factor for the efficacy of this short protocol, which was well tolerated by patients. In only 1 case were major side-effects observed. In spite of its short duration, the exchange treatment plus concomitant immunosuppressive drug therapy was not followed by early clinical deterioration.

Adolescent↗
PubMed1991

Neutrophil chemotaxis in infants delivered by caesarean section.

We evaluated polymorphonuclear leucocyte (PMN) chemotaxis and cortisol levels in cord blood from 15 healthy term infants delivered by caesarean section and from 15 healthy vaginally delivered term infants. Mean neutrophil chemotaxis was significantly higher in infants delivered by caesarean section (78.3 +/- 23.4 microns) than in vaginally delivered infants (57.8 +/- 16.6 microns; P = 0.01). Mean blood cortisol level was significantly lower in infants delivered by caesarean section (9.14 +/- 2.76 micrograms/dl) than in infants born by vaginal delivery (20.71 +/- 6.98 P = 0.0001). No relationship was found between PMN chemotaxis and blood cortisol level. The higher neutrophil chemotactic activity observed in infants delivered by caesarean section could be related to general maternal anaesthesia.

Anesthesia, General↗
PubMed1991

The epidemiology of inflammatory polyradiculoneuropathy. A critical review of the distribution, characteristics and outcome of the disease. Plasmapheresis Study Group.

An outline of the principal reports dealing with the definition, distribution, course and treatment of the inflammatory polyradiculoneuropathies, including the Guillain-Barré syndrome (GBS) and chronic inflammatory demyelinating polyneuropathy (CIDP), is given. Current diagnostic criteria for GBS are reaffirmed while the diagnosis of CIDP lacks proper standardization. Then, the boundaries between the two disorders are ill-defined. While GBS is rare and homogeneously distributed across developed and developing countries, the prevalence rate of CIDP is unknown. Several antecedent events have been implicated in the pathogenesis of GBS; yet, except for the swine-flu vaccine, the relation between infectious or toxic agents and the occurrence of the disease is purely anecdotal. The only factors known to influence the outcome of GBS are age, severity of opening symptoms, abnormal electrophysiologic characteristics of peripheral nerve function, and plasmapheresis. However, responders and non-responders to current treatment are far from defined. Although similarities have been found between experimental allergic neuritis and experimental allergic encephalomyelitis, the degree of CNS impairment in patients with inflammatory polyradiculoneuropathies needs further refinement. To provide a tentative answer to some of the unsolved questions on inflammatory polyradiculoneuropathies, a multicenter cohort study on newly diagnosed patients submitted to standard clinical and laboratory evaluation, and given common therapeutic regimes, is awaited.

Central Nervous System↗
PubMed1991

Immunoglobulin G3-specific antibodies as a marker for early diagnosis of HIV infection in children.

Early diagnosis of HIV infection in the child of an HIV-infected mother may be difficult as HIV-specific immunoglobulin (Ig) G antibodies are transmitted to the fetus transplacentally. In an attempt to provide a new, simpler tool for early identification of HIV-infected children we analysed the HIV-specific IgG subclass pattern during the first year of life. One hundred and one samples were collected from 35 children born to HIV-seropositive mothers, among whom 18 seroreverted during follow-up and 17 were HIV-infected (two P1 and 15 P2 according to the Centers for Disease Control classification). Serum HIV-specific IgG3 was detectable at least in one sample in 26 out of 35 children. All 17 HIV-infected children showed persistently detectable specific IgG3, both with stable or progressive disease. Out of the 18 uninfected children who seroreverted during follow-up, nine were HIV-specific IgG3-negative when first tested and nine lost HIV-specific-IgG3 within 28 weeks after birth. The correlation of the serological results with clinical information and any other diagnostic tool on each child suggests that the clearance of specific-IgG3 antibodies heralds seroconversion in uninfected passive antibody-carrier children. This observation provides the basis for a new, simple and effective method for early diagnosis of HIV infection in children born to seropositive mothers.

Biomarkers↗
PubMed1991

Smoking habits and sporting activity among adolescents in north Italy.

A cross-sectional survey of the smoking habits of 330 17-19 year-old males practising physical activity as members of sports teams, and of 366 male students in the same age range was carried out in Brescia, North Italy. A total of 23.3% of the athletes and 30.9% of the students smoked at least one cigarette a week (chi 2 = 4.60, p less than 0.05), and 17.3% and 19.7% smoked at least one cigarette a day, respectively (chi 2 = 0.51; p greater than 0.05). The smoking athletes had on average 50.3 cigarettes/week and students 47.0 (t-test: 0.46; p greater than 0.05). No difference was found with respect to age at their first experience with smoking, while athletes began to smoke regularly before than students, proportionally (chi 2 for linear trend: 5.29, p less than 0.05). Sporting activity was negatively associated with current smoking by multiple logistic regression: the odds ratio of current smoking for athletes with respect to students was 0.5 (95% CI: 0.4-0.8). Among a set of social, environmental and behavioural variables, best friend's and girlfriend's smoking was the one most strongly associated with current smoking in both groups.

Adolescent↗
PubMed1991

[Echocardiographic and cardioangiographic evaluation of non-Q infarction with isolated stenosis of the anterior descending artery].

We studied with two-dimensional echocardiography and coronary angiography 2 groups of patients with one-vessel stenosis located on anterior descending (IVA) and previous acute myocardial infarction (AMI; means 19 days): 23 patients with spontaneous non-Q infarction (Group I), and 23 patients with Q infarction (Group II). Left ventricular function was better in Group I (echo score: 2.04 +/- 2.64, angiographic ejection fraction: 65.65 +/- 9.7 in Group I, echo score: 4.78 +/- 3.14, angiographic ejection fraction: 49.47 +/- 9.1 in Group II, p less than 0.001). Percent occlusion of IVA was lower in Group I and angiographic IVA caliper was significantly higher (p less than 0.05). Differences between groups were much more evident in subgroups with proximal stenosis of IVA: patients of non-Q subgroup had very good left ventricular function but frequently had post-IMA unstable angina (78%). Our results underline usefulness of aggressive diagnostic and therapeutic approach in non-Q AMI, because of higher amount of myocardial a risk.

Adult↗
PubMed1990

Spontaneous NBT reduction by monocytes as a marker of disease activity in children with histiocytosis.

In an attempt to define a biological marker of monocyte hyperactivation in the course of infantile histiocytosis, the spontaneous nitroblue tetrazolium (NBT) reduction assay was applied to monocytes from 13 children with Langerhans cell histiocytosis (LCH), familial haemophagocytic lymphohistiocytosis (FHL), juvenile xanthogranuloma or malignant histiocytosis. Significant increase in NBT reduction was observed in the patients with both active LCH and FHL in comparison with control subjects, who were either healthy or affected by different conditions. A close relationship between spontaneous reduction rate and clinical condition of the patients was evident in patients tested at diagnosis, during remission and during the course of disease reactivation. Interleukin-1 (IL-1) production by monocytes was also evaluated: the patients with LCH and FHL displayed a significant increase in in vitro IL-1 production by lipopolysaccharide-stimulated monocytes. In our experience the spontaneous NBT reduction assay was a sensitive, quite specific, low-cost and reproducible test for the evaluation of children with histiocytosis. Useful information may be obtained at diagnosis but also during the clinical course of disease by using this marker of monocyte spontaneous activation.

Adult↗
PubMed1990

Prevalence of hepatitis C virus antibodies in Italian blood donors. The Italian Cooperative Group.

11,117 blood donors from 24 blood transfusion services evenly distributed throughout the various Italian regions were tested for the presence of hepatitis C virus (HCV) antibodies in the serum and serum alanine aminotransferase (ALT) level. The results are as follows: (1) anti-HCV seroprevalence in Italy was 0.87% with a difference between Northern and Southern regions (0.68 vs. 1.37%) and between younger and older subjects (0.62 vs. 1.21%); (2) prevalence of elevated ALT levels was 4.74% without a North-South effect (except than for markedly elevated ALT levels); (3) anti-HCV seroprevalence was higher in subjects with elevated ALT (5.0%), with a North-South effect (2.2 vs. 9.9%) and particularly high (19.2%) in subjects with markedly elevated ALT; (4) ALT levels were elevated in 26.2% of anti-HCV positive subjects, with a North-South effect (14 vs. 40.5%).

Adult↗
PubMed1990

Usefulness of 1-hour and 24-hour heart rate Holter inbuilt in new TX* rate adaptive pacemakers.

The rate adaptive TX* pacemaker uses the evoked QT interval as an indicator of physiological demand. In order to obtain a rate adaptation close to physiological patterns we used in the past, in each patient, on the slope value and/or the T wave sensing window, controlling via exercise stress testing and Holter the results achieved. It was an expensive method, but the system produced effective rate responsive pacing. The new series of TX* pacemakers (Quintech 919 and Rhythmyx), beside the dynamic slope feature, are equipped with a 1-hour heart rate Holter (HRH) that can be used during effort without the need for manually recording the heart rate. In this mode TX* pacemakers calculate the average heart rate over 20-second periods and stores the values continuously for 1 hour. In addition, a 24-hour HRH is available, which calculates the average heart rate over 7.5-minute periods, showing heart rate trend during the last day prior to interrogation. Each HRH can be accessed by the programmer and printed out. Using four Quintech 919* and five Rhythmyx units, the inbuilt HRH proved its utility by making the heart rate adaptation checking procedure easier, faster, and more economic.

Atrial Fibrillation↗
PubMed1990

[Anesthesia and the chemotaxis of neutrophilic granulocytes in newborn infants].

The authors investigated the modifications of neutrophil chemotaxis and cortisol plasma levels in the newborn delivered by cesarean section or vaginal delivery. Chemotaxis turned out to be higher in the group undergoing cesarean section, while cortisol was lower in this group. The increased activity of neutrophils can be explained with the lessened inhibitory effect of endogenous steroids and with the stimulating action of nitrous oxide.

Anesthesia, Obstetrical↗
PubMed1989

Effectiveness of erythrocytapheresis in idiopathic hemochromatosis. Report of 14 cases.

Thirteen men and one woman (mean age 48.8 yr +/- 6.9, range 36-63) with idiopathic hemochromatosis were treated by erythrocytapheresis. Iron depletion followed 9.60 months treatment (median 24), with 21-203 erythrocytaphereses (mean 93 +/- 61) and total iron removal of 4.2-40.6 g (mean 19 +/- 11.9). Trasferrin saturation decreased from 90 +/- 8.7% to 17 +/- 10.6% and serum ferritin from 3164 micrograms/L +/- 1488 to 60.5 micrograms/L +/- 77.5, and liver iron content normalized in all cases. Initial serum ferritin in the patients who were iron-depleted at 18 months (50%, cumulative percentage) was significantly lower than in those still iron loaded at that time (2280 micrograms/L +/- 940 vs 4049 micrograms/L +/- 1444, p less than 0.02). Clinical improvement was noted in all cases with about a 30% decrease in insulin requirement in most diabetics. Thus erythrocytapheresis appears to be effective and safe in obtaining iron depletion in idiopathic hemochromatosis.

Adult↗
PubMed1988

Diagnostic value of body surface potential mapping in old anterior non-Q myocardial infarction.

Body surface potential maps (BSM) were recorded from 140 chest leads in 30 healthy control subjects (C) and in 20 patients who had had an acute non-Q wave myocardial infarction (MI) 1-82 months before the study, to identify reliable indices of necrosis. In 12 MI patients the QRS complex was within normal limits on standard 12-lead ECG (group A), and in 8 patients no pathologic Q waves were present but the R waves were small and did not normally increase from V1 to V4 (group B). In each subject instantaneous potential distributions throughout the QRS interval were examined. Moreover, the potential--time integrals relating to three intervals (first 40 msec, mid-third, and last third of QRS) were calculated at each lead point and displayed as integral (I) maps. For each time interval, deviation index maps (DI), indicating the standardized differences from normal values, were calculated. An area where the integral values differed at least 2 SD from normal mean was considered abnormal. In most group A patients the inspection of instantaneous potential maps did not reveal definitively abnormal patterns. In group B patients a greater variety of patterns was found and in four cases the characteristic features of the anterior Q wave MI were observed. The DI maps of the first 40 msec of QRS provided the best diagnostic accuracy: areas of negative values 2 SD lower than normal were present in all group B patients (100%), in 8 group A patients (67%), and in 4 group C subjects (13%).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1988

Multiple and complex effects of buspirone on central dopaminergic system.

The effects of the anxiolytic drug buspirone and its metabolite 1-PP on the dopaminergic system were investigated. A single buspirone administration was found to decrease DA levels and increase its metabolite DOPAC in striatal samples. The levels of the other DA metabolite, 3MT, were unaffected; however its formation rate after inhibition of its metabolism, was found to be increased by buspirone. 1-PP did not affect either DOPAC or 3MT levels and formation. Striatal microdialysis showed that buspirone enhances DA release. In vivo voltammetry indicates that the increase of DA metabolism is identical in the two sampled dopaminergic areas, striatum and nucleus accumbens. On the basis of the results obtained ex vivo and in vivo the multiple effect of buspirone on dopaminergic system is discussed.

Animals↗