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Biomedical subjects

M Floriani

Publications and source records attributed to M Floriani.

At least 19 recordsLinked to original sources
PubMed2006

Effects of chronic internal alpha irradiation on physiology, growth and reproductive success of Daphnia magna.

Daphnids were chronically exposed to waterborne Am-241, an alpha-emitting radionuclide, ranging in concentration from 0.4 to 40 Bq ml(-1). Am-241 amounts were monitored in the medium, daphnid tissues and cuticles. Corresponding average dose rates of 0.02, 0.11 and 0.99 mGy h(-1) were calculated for whole organisms with internal alpha-radiation contributing 99% of total dose rates. Effects of internal alpha irradiation on respiration and ingestion rates, adult, egg and neonate individual dry masses, fecundity and larval resistance to starvation were examined in 23-day experiments. Daphnids showed increased respiratory demand after 23 days at the highest dose rate, suggesting increased metabolic cost of maintenance due to coping with alpha radiological stress. Although no effect was detected on ingestion rates between contaminated and control daphnids, exposure to dose rates of 0.11 mGy h(-1) or higher, resulted in a significant 15% reduction in body mass. Fecundity remained unchanged over the 23-day period, but individual masses of eggs and neonates were significantly smaller compared to the control. This suggested that increased metabolic expenditure in chronically alpha-radiated daphnids came at the expense of their energy investment per offspring. As a consequence, neonates showed significantly reduced resistance to starvation at every dose rate compared to the control. Our observations are discussed in comparison with literature results reported for cadmium, a chemical toxicant which affects feeding activity and strongly reduces individual energy uptake.

Age Factors↗
PubMed2006

Phosphate deficiency promotes modification of iron distribution in Arabidopsis plants.

Phosphate (Pi) is an essential element for plant development and metabolism. Due to its low availability and mobility in soils, it is often a limiting nutrient for their growth. This phenomenon is reinforced by the formation of insoluble complexes in the environment with many cations, affecting the solubility of both phosphate and associated ions. This interaction is investigated here for iron, a strong phosphate chelator. Depleting the medium in phosphate clearly resulted in an increase of iron content in Arabidopsis. These modifications triggered molecular responses linked with iron status (transport, homeostasis and accumulation). Interestingly, physiological modifications affecting iron storage were also observed. The accumulation of phosphate/iron complexes in the vacuoles of plants grown in Pi-rich medium disappeared in Pi-depleted medium in favor of accumulation of iron inside the chloroplasts, likely associated with ferritin.

Arabidopsis↗
PubMed2005

Dramatic development of severe SLE in a patient with an incomplete disease.

This case report describes the previously-unreported clinical course of a patient with a so-called incomplete systemic lupus erythematosus (SLE), i.e. symptoms related to one organ system only, together with the presence of ANA. He had an indolent course initially and developed, 6 months after the first symptoms, a severe disease with rapid appearance of major and unusual manifestations. The possibility of fast progression and a grave course of an incomplete SLE should be kept in mind. This report is meant to heighten awareness of such an atypical presentation so that prompt and aggressive immunosuppressive therapy may be instituted.

Abdomen, Acute↗
PubMed1991

Monitoring of somatosensory evoked potentials during carotid endarterectomy: relationship with different haemodynamic parameters and clinical outcome.

The authors studied the changes of Somatosensory Evoked Potentials (SEPs) performed in 241 anaesthetised patients during 264 carotid endarterectomies (CEs). SEP responses were considered significantly modified when the central conduction time was greater than 1 ms and/or when the amplitude of the complex N20-P25 decreased by at least 50%. Both CCT and N20-P25 have been correlated with different parameters, including the presence or absence of preoperative neurological deficits, the type of general anaesthesia, the status of the contralateral and the ipsilateral carotid artery, stump pressure, the use of an intraluminal shunt and the perioperative results. After carotid cross-clamping SEP responses were within the normal range in 236 CEs (89%), and abnormal in 28 (11%). A shunt was inserted 23 times in 264 (9%) cases. None of the patients operated on in this series experienced a permanent neurological deficit; there were three (1.1%) transient deficits (two Rinds and one TIA) and two deaths from non-neurological causes. Only one of the transient deficits was present when the patient woke from the anaesthetic and this event was predicted by significant modification of the SEP which did not reverse after removal of the clamps (a shunt was not used). None of the patients in our series who did not present significant modifications of SEPs during the operation had any postoperative neurological deficit. The authors conclude that SEP recording is a highly reliable and objective method for continuous monitoring of brain function during CE.

Brain Ischemia↗
PubMed1990

Immediate detection of postreconstructive ischaemia by intra-operative Doppler ankle pressure index monitoring during aortic reconstructions.

From March 1980 to February 1988, 368 aorto-iliac or aorto-femoral bilateral reconstructions were performed for aneurysmal or occlusive disease. In order to demonstrate early postreconstructive ischaemic complications, the intra-operative Doppler Ankle Pressure Index (API) was measured immediately before reconstruction (PRE), just after declamping (DEC) and 5, 15, 30 and 45 min thereafter. Each limb of the reconstruction (736) was considered individually and subdivided as follows: Group (A) 705 immediately successful (96% of limbs and 92% of patients); Group (B) 22 (3% of limbs and 5% of patients) in which, on the grounds of API data, an ischaemic complication was regarded as imminent and treated by graft revision or a peripheral thromboembolectomy (intra-operative corrections); Group (C) 9 (1% of limbs and 2% of patients) in which the diagnosis of ischaemic complications was made postoperatively when the patients underwent successful reoperation. All 736 reconstructions were patent and functional at discharge of the patient. By a retrospective analysis the intra-operative APIs were studied and the features (single or associated) suggesting an ischaemic complication examined. These were: (1) no flow at the time of declamping or its disappearance during the operation (10 cases, 1.25% of limbs) all detected and successfully corrected intra-operatively.(ABSTRACT TRUNCATED AT 250 WORDS)

Ankle↗
PubMed1990

[Carotid thromboendarterectomy in old age].

Data obtained in 323 carotid bifurcation endarterectomies and in 77 patients affected by extracranial internal carotid artery stenosis not operated, have been analyzed in relation to patients' age: Group 1 less than or equal to 69 years old (268 cases operated on and 59 not operated), and Group 2 greater than or equal to 70 years old (55 cases operated on and 18 not operated). Among the operated patients, the most important anaesthetic risk factors, the type of neurological symptoms, and the diameter of the lesion did not turn out significantly different between the two age groups, except for the patients operated on because of stenoses less than or equal to 50% of carotid lumen reduction (42 cases in Group 1 and 1 case in Group 2, p less than 0.001). The overall operative mortality rate was 1.8% (6/323 carotid endarterectomies): 1.5% in Group 1 (4/268 cases, 2 due to stroke and 2 to heart disease), and 3.6% in Group 2 (2/55 cases, both due to stroke) (N.S.). The overall neurological morbidity was 0.6%, owing to 2 strokes both found in Group 2 (3.6% of patients greater than or equal to 70 years). Therefore, the overall incidence of fatal and non fatal stroke was 1.8% (6/323 carotid endarterectomies): 0.7% (2 cases) in Group 1, and 7.3% (4 cases) in Group 2 (p less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Age Factors↗
PubMed1989

Predictive value of cervical bruit for the detection of obstructive lesions of the internal carotid artery. Data from 2000 patients.

Between January 1982 and June 1985, 2000 patients with either symptoms of cerebrovascular insufficiency (1873) or asymptomatic cervical bruits (127) were studied at the Surgical Department of the University of Brescia (Italy). Of these, 441 presented a mono- or bilateral cervical bruit. The value of the bruit as indicator of an obstructive pathology of the extracranial carotid artery was evaluated in comparison with the findings of Doppler spectrum analysis. A stenosis or occlusion of the internal carotid artery was present in 51% of the patients with a bruit (homolateral to the bruit in 91% of the cases) and in 9% of those without a bruit. Stenoses of a medium-high degree were those more often associated with the bruit. Both in patients with bruit and in those without bruit the age and the severity of the presenting symptoms significantly influenced the rate of association with lesions of the internal carotid artery was present in 51% of the patients with a bruit (homolateral to the bruit in 91% of the cases) and in 9% of those without a bruit. Stenoses of a medium-high degree were those more often associated with the bruit. Both in patients with bruit and in those without bruit the age and the severity of the presenting symptoms significantly influenced the rate of association with lesions of the internal carotid artery.

Adult↗
PubMed1989

[Splenic autografts in omental and subcutaneous pouches. An experimental study].

An accurate morphological study has been done on splenic grafts in rats after 7-15-30 days from their implant in omental or subcutaneous pouches. Observation after 7 days confirmed the necrosis of all the central portion of the implants. Anyway, marginal parts of the graft survived to ischaemia and showed to be supplied by vessels, coming from the contiguous tissues. In these parts the rigenerative process had begun from the structures of red residual pulp, by reticular cells proliferating so to rigenerate the capsula limiting the place of the central necrotic area. After 15 days the neocapsula was completed and from it neoformed trabecolae departed accompanied with chords, sinus capillary, venular and arteriolar vessels which reformed the structure of red pulp both in peripheral and central area, now undistinguishable. After 30 days lymphocytes aggregating around the neoformed vessels promoted a rudimental reconstruction of the white pulp too. In conclusion, splenic implants are able to get over the ischaemic phase and after 30 days the red pulp is morphologically reconstructed and probably functioning, while the white pulp is still primordial.

Animals↗
PubMed1989

Influence of contralateral carotid artery on neurologic outcome after carotid endarterectomy.

The discrepancy in the literature about the immediate results after carotid endarterectomy in the presence of occluded or seriously stenotic contralateral carotid artery, has encouraged a retrospective study on 230 patients subjected to 255 carotid endarterectomies. 63 operations (group 1) were carried out in the presence of occluded contralateral carotid artery (40 operations) or of seriously stenotic contralateral carotid artery (23 operations). In the remaining 192 operations (group 2) the contralateral carotid artery was normal or not significantly stenotic (less than 60% of diameter reduction). The indication for surgery and age and sex distribution were similar in the two groups. No operations were performed during acute stroke. Patients with previous stroke underwent surgery only after at least 1 month from the onset of symptoms, in stable neurological conditions. All the patients were operated on under general anesthesia and with systemic heparinization; the indication for intraluminal shunt was made on the basis of clinical evaluation, of back pressure value and, in 106 operated cases of somatosensory cortical evoked potentials. At the end of every operation, ultrasonographic and/or angiographic instrumental controls were carried out. No statistically significant difference was evidenced in the incidence in groups 1 and 2 of postoperative transitory neurological insufficiency (both 3.2%, P greater than 0.8), of permanent neurological insufficiency (0% and 1%, P greater than 0.9), of mortality because of neurological (3.2% and 1%, P greater than 0.5) and non neurological causes (1.6% and 0%, P greater than 0.1).(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1989

[Peroperative morbidity and mortality in thromboendarterectomy of the carotid bifurcation in patients with a previous stabilized stroke. Our results and review of the literature].

Carotid endarterectomy (CE), when performed in patients with previous stable stroke followed by complete or almost complete recovery, seems to be affected by a higher peroperative risk. From January 1982 to March 1988, we performed 230 CE in 207 patients, 188 (81.8%, Group 1) in patients with TIA or an asymptomatic plaque and 42 (18.2%, Group 2) in patients with previous strokes. The need for a temporary indwelling shunt has been evaluated with the measurement of carotid back pressure and, in the last 100 CEE, with the monitoring of somatosensory evoked responses (the shunt has however been used routinely anyway in the very first part of our experience). The incidence of carotid back-pressure values and of positive somatosensory evoked responses were similar in the two groups of C.E., even if the differences in the prealable evaluation were not statistically significant. The shunt has been nevertheless used more frequently in Group 2 (40.5 vs 28.2%). Statistical analysis has been performed with the chi 2 method. The incidence of permanent and transient neurologic deficits and of the peroperative mortality due to neurological and non-neurological causes was, respectively, 0.5, 2.6, 1.6, 0% (Group 1) and 2.4, 7.3, 2.4, 2.4% (Group 2) (non-significant). If we exclude the first 50 operations (in which technical and/or anaesthesiological problems may have influenced the neurological outcome of the patients operated upon), the previous values become, respectively, 0,07*, 0,7, 0% (Group 1) and 0, 5,5*, 0, 2,7% (Group 2) (*p less than 0,01, the only significant difference).(ABSTRACT TRUNCATED AT 250 WORDS)

Carotid Artery Diseases↗
PubMed1988

Value and limits of "critical auscultation" of neck bruits.

Within a group of 2,000 patients evaluated, most of them with symptoms of cerebrovascular insufficiency, 441 had a monolateral or bilateral cervical bruit. The 627 sides with an audible bruit were divided into main groups (A) symptomatic (TIA and/or stroke homolateral to the bruit), (B) possibly symptomatic (non-side-related symptoms), (C) asymptomatic (C1, in totally asymptomatic patients; C2, in patients with symptoms dependent on the hemisphere contralateral to the cervical bruit). Each patient was studied by means of clinical (history, blood pressure in both upper limbs, phonoendoscopic auscultation at various levels) and noninvasive instrumental examinations (CW Doppler spectrum analysis). An apparently primitive cervical bruit corresponded to a lesion of the carotid bifurcation in 61% of the cases (positive predictive value) whereas a normal bifurcation was detected in 70% of the cases in which the cervical bruit was considered as secondary (negative predictive value); the diagnostic accuracy of the "critical auscultation" has a value therefore of 63%, with a sensitivity of 84% and a specificity of 40%. The results obtained in the different groups of patients (symptomatic or asymptomatic) were not significantly different (chi-square). Even though maintaining the value of a cervical bruit as a sign of carotid stenosis or occlusion and consequently confirming the importance of neck auscultation, the authors conclude that the critical auscultation as commonly performed is not capable of excluding the presence of a carotid lesion with sufficient reliability, even in totally asymptomatic patients.

Auscultation↗