Biomedical subjects

A Romani

Publications and source records attributed to A Romani.

At least 73 records · Page 4Linked to original sources

PubMed1996

Mediastinoscopy, thoracoscopy and left anterior mediastinotomy in the diagnosis of N2 non small cell lung cancer.

The preoperative diagnosis of the involvement of the N2 lymph nodes is very important in patients with NSCLC for the most appropriate treatment. The classical diagnostic techniques for mediastinal exploration, mediastinoscopy and left anterior mediastinotomy, have been recently integrated by videothoracoscopy. FromJanuary 1993 to April 1994 186 patients with NSCLC suitable for surgery, were observed in our Department. 18 patients (9%) had CT evidence of N2 disease. In 10 cases the sites of the nodal enlargement were the right paratracheal station (#2 according to Naruke) and the right tracheobronchial station (#4), in 4 the subcarinal station (#7), in 2 the subaortic (#5) and in the remaining 2 cases the paraaortic station (#6). 14 mediastinoscopies were performed to investigate the stations 2,4 and 7,2 videothoracoscopies for station 5 and 2 left anterior mediastinotomies for station 6. The histological diagnosis was obtained in all cases without intraoperative or postoperative complications. Because the sequence chemotherapy-surgery seems to obtain the best results in the treatment of N2 disease the preoperative diagnosis of nodal involvement is of outstanding importance. Until recently mediastinoscopy and anterior left mediastinotomy were considered the standard techniques to explore mediastinum, now also videothoracoscopy has been introduced. In our experience, the integration of all the above techniques allowed a complete study of each suspect N2 site. Particularly the videothoracoscopy is very useful to safely biopsy under direct vision the aortic window lymph nodes.

Biopsy↗

PubMed1996

Electromyographic evaluation of the spared serratus anterior after postero-lateral thoracotomy.

Postero-lateral thoracotomy is the standard access in thoracic surgery, and can be carried out dividing or preserving the serratus anterior muscle. This last method, besides its advantages, is still a matter of discussion, in fact traction has been claimed to cause severe muscular damage equal to section. We have studied 20 patients (16 males and 4 females, mean age 63 years), who underwent postero-lateral thoracotomy sparing the serratus anterior, after 6 months from surgery, both clinically and by means of electromyography (EMG), to evaluate the functional status of the spared muscles. In 4 cases (20%) there wasn't any neurogenic damage nor clinical evidence of winging scapula; 3 cases (15%) had medium neurogenic damage. The remaining 13 (65%) cases had a medium neurogenic damage and only one patient showed a winging scapula, neverthless being able to lift the arm to shoulder level. Our data confirmed that retraction during surgery does not damage the serratus anterior, leaving a functionally valid muscle.

Aged↗

PubMed1995

Pavia memory project: study design and first results.

This paper describes the design and first results of the cross-sectional phase of a study on memory impairment in elderly subjects (Pavia Memory Project). The target population consisted of the 1,046 subjects born in 1925 and currently living in Pavia. Four hundred and thirty-six subjects (plus 287 interviewed at home) participated in the first stage, which consisted of a semi-structured anamnestic interview. The 400 interviewed subjects with none of the exclusion criteria participated in the second stage, which consisted of a memory test battery, a standardized neurological examination and screening procedures for depression (GDS) and dementia (MMSE). On the basis of the memory scores, three groups were defined: memory impairment (MI: 8.8%), mild memory impairment (MMI: 39.8%); normal (N: 51.3%). There were more failures on the visuo-spatial memory tests. Depression was equally distributed in the N and MI groups (about 15%), but was more frequent in the MMI group (27%). Abnormal neurological signs were largely independent of memory performance. Two cohorts (of MI and N subjects) underwent neuropsychological and instrumental (CT-scan, EEG, ERPs, eye movements) assessment, which will be regularly repeated in the longitudinal phase.

Aged↗

PubMed1995

Recovery functions of early cortical median nerve SSEP components: normative data.

The recovery functions of parietal P14-N20, N20-P27 and frontal P22-N30 amplitudes were assessed in 17 healthy controls aged 20-50 years by means of the paired stimulus technique. One unpaired and 4 paired stimuli with interstimulus intervals (ISIs) of 25, 50, 75 and 100 msec were cyclically presented in a single run. Responses to the unpaired stimulus were subtracted off-line from paired stimulus responses. The highest suppression was reached at shorter ISIs for components with shorter latencies. The mean suppression of P22-N30 was influenced by the subject's age, being greater in younger subjects. Normative data are reported.

Adult↗

PubMed1995

Differential regulation of circulating Mg2+ in the rat by beta 1- and beta 2-adrenergic receptor stimulation.

Extracellular Mg2+ homeostasis was studied in vivo in the anesthetized rat. Animals were infused with isoproterenol (ISO) for 10 minutes, and serum Mg2+ was measured after the infusion and then 10 and 20 minutes later. A dose-dependent increase in circulating Mg2+ was observed in animals infused with ISO at a rate of 0.1 microgram.kg-1.min-1 or higher. The time course of the effect demonstrated that circulating Mg2+ continued to increase 20 minutes after the end of the ISO infusion. A predicted maximal increase in serum Mg2+ concentration of 19.3% was derived with a predicted EC50 of 0.08 microgram.kg-1.min-1. The maximal percent increase corresponded to a net increase of 6.7 mumol/300 g body wt. Because infusion of ISO resulted in changes in hemodynamic parameters, most notably a drop in blood pressure, a group of animals was infused with nitroprusside to mimic the hypotensive response via a nonadrenergic mechanism. Under these conditions, there was a transient increase in circulating Mg2+ that was largely inhibited by propranolol, indicating that hypotension per se was not responsible for the mobilization of Mg2+. Infusion of salbutamol, but not prenalterol, also induced an increase in circulating Mg2+. Pretreatment with butoxamine, ICI-118551, or propranolol prevented the ISO-induced increase in serum Mg2+. Pretreatment with atenolol minimally affected the ISO-induced changes in circulating Mg2+. Pretreatment with CGP-20271A actually enhanced the ISO-induced increase in circulating Mg2+. This evidence demonstrates the existence of a pool of Mg2+ that is mobilized into the circulation in response to selective beta 2-adrenergic stimulation.

Adrenergic beta-Antagonists↗

PubMed1995

[Probable HIV transmission by female homosexual contact].

Here we report a case of HIV infection in a lesbian lacking other risk factors. She had sought advice for asthenia and unexplained weight loss. The physical examination disclosed oropharyngeal candidiasis and generalized lymphoadenopathies. The patient defined herself as an active sexual partner and denied having any heterosexual intercourse whatsoever. Particle agglutination test proved positive for anti-HIV, as well as two consecutive ELISA assays, confirmed by Western blot. Since there was no history of blood transfusions or intravenous drug addiction, it may be concluded that HIV transmission was most likely due to female homosexual practices.

AIDS Serodiagnosis↗

PubMed1994

Usefulness of trigeminal somatosensory evoked potentials to detect subclinical trigeminal impairment in multiple sclerosis patients.

Trigeminal somatosensory evoked potentials (TSEPs) by surface electric pulse stimulation were recorded in 30 normal subjects and in 70 multiple sclerosis (MS) patients, 13 of whom presenting clinical trigeminal impairment. We observed significant prolongation of all TSEPs parameters in MS group. TSEPs were abnormal in 45 patients (64.3%). Clinical and neurophysiological data agreed in 36 patients (51%) on 84 sides (60%). TSEPs were able to detect clinically silent lesions 54 times. TSEPs recording proves to be an additional useful test in MS multimodal evoked potential protocols.

Adolescent↗

PubMed1994

[Treatment of dyslipidemia of the elderly with simvastatin and pravastatin. Effectiveness and tolerance].

After reviewing the literature concerning the advisability and efficacy of dyslipidemia treatment in old age, the authors present their experience with the use of HMG CoA reductase inhibitors. Twenty-five patients were treated with simvastatin and 20 with pravastatin. Already after one month of therapy, both drugs had induced a reduction of total cholesterol, LDL-cholesterol, and triglycerides, as well as an increase of HDL-cholesterol. These changes were found to be even more marked after three months of treatment. Altogether, tolerability of both drugs was good. However, recurrent episodes of nose bleeding were observed in two patients with normal blood clotting activity.

Aged↗

PubMed1994

Eye movement quantitative evaluation before and after high-dose 6-methylprednisolone in multiple sclerosis.

We studied saccadic and smooth pursuit eye movements in 24 patients suffering from multiple sclerosis during disease worsening, before and after high-dose 6-methylprednisolone infusions. Quantitative evaluation of saccades was based on amplitude/duration and amplitude/peak velocity relationships, precision (i.e. the ratio of actual to desired saccade amplitude) and the latency, whereas smooth pursuit eye movements were studied using target velocity/performance index relationship. At basal recordings, 22/24 (91.7%) of the patients showed at lest one abnormality. Eleven of the 24 patients (45.8%) showed modification of one or several parameters: improvement in 6 patients, worsening in 2, coexistence of both trends in 3. Latency improvement was the only significant modification when patients were considered as a group. Neurophysiological modifications did not correspond to clinical changes.

Adult↗

PubMed1993

Hormonal stimulation of Mg2+ uptake in hepatocytes. Regulation by plasma membrane and intracellular organelles.

Collagenase dispersed rat liver hepatocytes release Mg2+ when stimulated with norepinephrine or accumulate Mg2+ when stimulated with vasopressin, respectively. Mg2+ fluxes in either direction account for a net loss or gain of approximately 10% of total cell magnesium and are rapidly reversible. Both stimulated Mg2+ efflux and Mg2+ influx require physiological concentration of extracellular NaCl and Ca2+. In the absence of extracellular Na+, Mg2+ efflux, but not influx, can be observed in the presence of extracellular Cl-. Under these conditions, the efflux is inhibited by the Cl-/HCO3- exchanger inhibitor 4,4'-dinitrostilbene-2,2'-disulfonic acid. In hepatocytes, Mg2+ influx, but not efflux, is completely inhibited by thapsigargin, a specific inhibitor of the endoplasmic reticulum Ca2+ ATPase. Several lines of evidence, such as measurements of cytosolic Ca2+ or of cytosolic Ca2+ buffering, indicate that the effect of thapsigargin in inhibiting Mg2+ influx could not be explained by an increase in cytosolic Ca2+. Instead, the inhibition of hepatocyte Mg2+ influx was found to be the result of the depletion of the Ca2+ stored within the endoplasmic reticulum.

Animals↗

PubMed1993

Physiological concentrations of inorganic phosphate affect MgATP-dependent Ca2+ storage and inositol trisphosphate-induced Ca2+ efflux in microsomal vesicles from non-hepatic cells.

1. MgATP-dependent 45Ca2+ uptake by microsomes obtained from various non-hepatic tissues, namely rat brain, rat solid Morris hepatoma 3924A and human platelets, was measured in the presence of P(i) at low, cytosol-like, concentrations. 2. Increasing P(i) concentrations (0.5-3 mM) caused a progressive enlargement of the 45Ca(2+)-storage capacity of all the microsomal fractions. 3. As a result of P(i) stimulation of Ca2+ uptake, 45Ca2+ and [32P]P(i) were co-accumulated by the three microsomal fractions. 4. The time course for 45Ca2+ and [32P]P(i) accumulation in brain microsomes revealed a biphasic 45Ca2+ uptake: a rapid phase was followed by a second, slower, phase, which depended on the presence of P(i). During the P(i)-dependent phase, the uptake of 45Ca2+ was paralleled by the uptake of [32P]Pi. 5. The passive efflux of Ca2+ was paralleled by the efflux of P(i) and vice versa. In fact, the inhibition of active Ca2+ uptake by excess EGTA, or lowering the P(i) concentration of the incubation system by dilution, caused the release of 45Ca2+ and [32P]P(i) from 45Ca2+ or [32P]P(i) pre-loaded brain microsomes. The Ca2+ ionophore A23187 also released 45Ca2+ and [32P]P(i). 6. Ca2+ efflux by A23187 was rapid (t 1/2 approx. 2 s) and independent of the extent of intravesicular Ca2+ loading, which indicates that Ca2+ and P(i) do not form intravesicular insoluble complexes. 7. The progressive increase in Ca2+ accumulation, depending on P(i) stimulation, resulted in a proportional increase in the amount of Ca2+ releasable by InsP3 in the three non-hepatic microsomal fractions and in digitonin-permeabilized platelets. 8. Concomitantly to Ca2+, microsomal P(i) was also released by InsP3.

Adenosine Triphosphate↗

PubMed1993

A clinically oriented approach to smooth pursuit eye movement quantitative evaluation.

The electrooculographic technique was used to record smooth pursuit eye movements in 71 healthy subjects homogeneously distributed within an age range between the 2nd and the 6th decades. The target moved at constant velocity (triangular ramps) and 9 different target velocities (V), from 10 deg/s to 50 deg/s were considered and presented according to pseudorandom sequence. Ad hoc software suppressed catch-up saccades so that a pursuit index (PI) value was computed for each ramp taking into account only the smooth pursuit tracking modality. It was demonstrated that the relationship between V and PI could be described by the linear model PI = a + b * V. Pursuit index was proved to be influenced by the age of subject (decade factor in the analysis of variance), since an almost linear increase in b values yields a reduction of pursuit index values. The method was tested in 22 multiple sclerosis patients and an association was found between the occurrence of cerebellar signs and the reduction of a value.

Adolescent↗

PubMed1993

Regulation of magnesium uptake and release in the heart and in isolated ventricular myocytes.

Perfused rat hearts release or accumulate approximately 10% of total Mg2+ content when stimulated with norepinephrine (NE) or carbachol, respectively. Collagenase-dispersed rat ventricular myocytes increase or decrease total cell Mg2+ by 1 mM within 5 minutes when stimulated with these same transmitters. Measurements of Mg2+ transport using 28Mg or atomic absorbance spectrophotometry indicate that the rate and the extent of both stimulated Mg2+ efflux and influx are independent of the concentration of extracellular Mg2+ (0 to 1.2 mM). Mg2+ release induced by NE is rapidly reversed by the addition of carbachol, and Mg2+ uptake induced by carbachol is reversed by NE. Decreasing extracellular Na+ or Ca2+ decreases or abolishes Mg2+ efflux from myocytes. Cd2+ or other Ca2+ channel blockers also inhibit Mg2+ efflux in the presence of a physiological concentration of extracellular Ca2+. Replacement of extracellular Ca2+ with Sr2+ or with Mn2+ decreases or abolishes both stimulated efflux and influx of Mg2+. Redistribution of 85Sr in myocytes and in the supernatant indicates that under those conditions Sr2+ is released or accumulated by NE or carbachol in a manner similar to that of Mg2+. Hence, at least in the case of Sr2+, the inhibition of Mg2+ fluxes can be explained by the transport of Sr2+ rather than Mg2+ through the transport(s) systems. By contrast, replacement of extracellular Ca2+ with Ba2+ inhibits stimulated Mg2+ uptake but not Mg2+ release. These results indicate that cardiac myocytes have a major pool of Mg2+ that can be rapidly mobilized upon hormonal stimulation. The net uptake and release of Mg2+ are quantitatively similar and appear to be independent of the extracellular Mg2+ concentrations but are affected, to various degrees, by the presence of other cellular or extracellular cations.

Animals↗

PubMed1993

Neurophysiological parameters during halothane anaesthesia in experimental models of cerebral ischemia.

Types of anaesthesia in different experimental models of ischemia vary, with consequent difficulties in analysis of results obtained by the authors. The aim of this work was to evaluate EEG and SEPs parameters in a group of rabbits submitted to anaesthesia with halothane. We used White New Zealand rabbits prepared for EEG recording according to the Monnier and Gangloff's stereotaxic method. SEPs were obtained by medial nerve stimulation according to a method standardized in our laboratory. Each animal was anaesthetized with halothane plus nitrous oxide and oxygen or halothane plus oxygen for surgical MAC, which was maintained for a time corresponding to the duration of surgical intervention. We evaluated all parameters in basal conditions and after the administration of anaesthesia until EEG and SEPs returned to basal values. Evoked potentials remained altered for a longer period of time and returned to basal levels only two hours after anaestethic suspension.

Anesthesia, Inhalation↗

PubMed1993

Somatosensory evoked potentials by median nerve stimulation recorded with cephalic and non-cephalic references. I). Normative study.

Somatosensory evoked potentials by median nerve stimulation were obtained in 50 healthy subjects (aged 15-70 years) with cephalic and non cephalic references. Most parameters were influenced by one or more independent variables (sex, age, arm lengths). The coefficients of the appropriate linear models are reported to compute correct individual normal limits.

Adolescent↗

PubMed1993

Somatosensory evoked potentials by median nerve stimulation recorded with cephalic and non-cephalic references. II). Reliability study.

Reliabilities of parameters of median nerve short-latency somatosensory, evoked potential obtained using both cephalic and non-cephalic references was measured in 20 healthy volunteers (aged 20-50 years) who repeated the recording session after one week. All latency measures and peak-to-peak times were highly reliable; amplitudes were less reliable. Upper normal test-retest variability limits of all the analyzed parameters were also computed.

Adolescent↗

PubMed1993

One-week test-retest reliability of spinal and cortical somatosensory evoked potentials by tibial nerve stimulation.

Spinal (Th12) and cortical somatosensory evoked potentials by right and left posterior tibial nerve stimulation at the ankle were performed in 20 healthy volunteers (10 females and 10 males) aged 23-50 years. The procedure was repeated after one week to assess the reliability of the parameters and to establish upper normal variability limits. Reliability was measured by the intraclass correlation coefficient and was excellent for all absolute latencies and at least good for amplitudes and for the spinal-cortical conduction time. Upper variability limits were calculated using a method based on the within-subject mean square, which can be also applied in the case of more than two repetitions.

Adult↗

PubMed1993

[The assessment of glucose tolerance in hypertensive subjects treated with amlodipine].

The authors studied the side effects of amlodipine on glucose metabolism, carrying out an oral glucose tolerance test before and after 8-10 days of treatment, in a group of subjects with normal glucose tolerance. No significant variation in the average plasma glucose and insulin levels was observed. Nevertheless, in some cases, during amlodipine therapy, a decrease in glucose plasma level was found.

Amlodipine↗