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Biomedical subjects

V Ferrari

Publications and source records attributed to V Ferrari.

At least 19 recordsLinked to original sources
PubMed2003

Oxygen stripes in La0.5Ca0.5MnO3 from ab initio calculations.

We investigate the electronic, magnetic, and orbital properties of La0.5Ca0.5MnO3 perovskite by means of an ab initio electronic structure calculation within the Hartree-Fock approximation. Using the experimental crystal structure reported by Radaelli et al. [Phys. Rev. B 55, 3015 (1997)]], we find a charge-ordering stripelike ground state. The periodicity of the stripes, and the insulating magnetic structure, consisting of antiferromagnetically coupled zigzag chains, are in agreement with neutron x-ray and electron diffraction experiments. However, the detailed structure is more complex than that envisaged by simple models of charge and orbital order on Mn d levels alone, and is better described as a charge-density wave of oxygen holes, coupled to the Mn spin/orbital order.

Journal Article↗
PubMed2001

[Hemolytic anemia associated with breast neoplasm].

We describe a patient with a microangiopathic hemolytic anemia, associated with thrombocytopenia, in consequence of breast cancer in an advanced phase. Microangiopathic hemolytic anemia is a rare and serious compliance of malignant neoplasms, in particular of breast and gastric carcinomas. Microangiopathic hemolytic anemia has always a serious prognosis: survivance in non-treated patients is of a few weeks. Our patient, treated by chemotherapy, has gained a partial remission of MHA, with a reduction of blood transfusions.

Anemia, Hemolytic↗
PubMed1999

N-acetylaspartylglutamate in Canavan disease: an adverse effector?

UNLABELLED: We measured N-acetylaspartate and its precursor/product N-acetylaspartylglutamate (NAAG) in urine of patients with Canavan disease using capillary zone electrophoresis. Abnormal levels of NAAG were found in 32 of 43 patients examined. Elevated NAAG was also present in the CSF of one patient. Given that NAAG may interfere with N-methyl-D-aspartate receptor function, the occurrence of high levels of NAAG in patients' urine conceivably represents a participating factor in the pathogenesis of Canavan disease. CONCLUSION: The biochemical role of N-acetylaspartylglutamate and its relationship to glutamatergic function may be relevant to the pathogenesis of Canavan disease.

Adolescent↗
PubMed1999

[Association of Lynch syndrome and non-Hodgkin's malignant lymphoma. A case report].

A patient is described, with Lynch syndrome, typified by hereditary appearance in young age of synchronous and metachronous proximal colorectal cancer, without polyposis, and often associated with extracolonic cancer, particularly ovarian and endometrial carcinomas. The study of our patient's pedigree showed the occurrence of eleven colonic cancers. Our patient had ovarian carcinoma, tumor of the rectum and non-Hodgkin's lymphoma.

Adenocarcinoma, Mucinous↗
PubMed1997

Learning and forgetting processes in Parkinson's disease: a model-based approach to disentangling storage, retention and retrieval contributions.

Learning and forgetting a prose passage was studied in 20 patients with Parkinson's disease and in 20 normal control subjects by means of stochastic models, with the aim of identifying the learning and retaining abilities that are affected by Parkinson's disease. Results suggested that Parkinson's disease patients are impaired in developing automatic processing both during learning and retaining, while functions that require active attention are spared. The automatic/intentional dissociation, which is the hallmark of motor disturbance in Parkinson's disease, extends to memory abilities, and, on the grounds of neuroanatomical, neurochemical and neurophysiological correlates, suggests that the memory deficit in Parkinson's disease may be contingent on a dysfunction of the medial prefrontal-cingulate cortex.

Aged↗
PubMed1997

Quercetin protects cutaneous tissue-associated cell types including sensory neurons from oxidative stress induced by glutathione depletion: cooperative effects of ascorbic acid.

Oxidation reactions are essential biological reactions necessary for the formation of high-energy compounds used to fuel metabolic processes, but can be injurious to cells when produced in excess. Cutaneous tissue is especially susceptible to damage mediated by reactive oxygen species and low-density lipoprotein oxidation, triggered by dysmetabolic diseases, inflammation, environmental factors, or aging. Here we have examined the ability of the flavonoid quercetin to protect cutaneous tissue-associated cell types from injury induced by oxidative stress, and possible cooperative effects of ascorbic acid. Human skin fibroblasts, keratinocytes, and endothelial cells were cultured in the presence of buthionine sulfoximine (BSO), an irreversible inhibitor of glutathione (GSH) synthesis. Depletion of intracellular levels of GSH leads to an accumulation of cellular peroxides and eventual cell death. Quercetin concentration-dependently (EC50: 30-40 microM) reduced oxidative injury of BSO to all cell types, and was also effective when first added after BSO washout. BSO caused marked decreases in the intracellular level of GSH, which remained depressed in quercetin-protected cells. Ascorbic acid, while by itself not cytoprotective synergized with quercetin, lowered the quercetin EC50 and prolonged the window for cytoprotection. The related flavonoids rutin and dihydroquercetin also decreased BSO-induced injury to dermal fibroblasts, albeit less efficaciously so than quercetin. The cytoprotective effect of rutin, but not that of dihydroquercetin, was enhanced in the presence of ascorbic acid. Further, quercetin rescued sensory ganglion neurons from death provoked by GSH depletion. Direct oxidative injury to this last cell type has not been previously demonstrated. The results show that flavonoids are broadly protective for cutaneous tissue-type cell populations subjected to a chronic intracellular form of oxidative stress. Quercetin in particular, paired with ascorbic acid, may be of therapeutic benefit in protecting neurovasculature structures in skin from oxidative damage.

3T3 Cells↗
PubMed1997

Mast cells contain large quantities of secretagogue-sensitive N-acetylaspartate.

Mast cells play a central role in both immediate allergic reactions and inflammation. A functional nerve-mast cell interaction has been proposed, given the morphological association between mast cells and neuropeptide-containing peripheral nerves. We now show that purified rat peritoneal mast cells contain large quantities of N-acetylaspartate (NAA; 747.50 nmol/mg of protein). Mast cell levels of NAA were rapidly reduced, by 64.0 and 86.4%, following treatment with compound 48/80 and mastoparan, respectively. These secretagogues strongly decreased mast cell histamine content over the same time period, suggesting also that NAA is stored in secretory granules. The data are the first to show that NAA is present in an immune effector cell type. Because NAA may be involved in myelin synthesis and glutamyl peptide metabolism, NAA released from mast cells following nervous or other stimuli could participate in neuroimmune interactions. Mast cells in multiple sclerosis plaques may contribute to the reported elevations in brain NAA in this disease.

Animals↗
PubMed1997

[Primary extranodal non-Hodgkin's lymphoma of muscle tissue].

Primary muscular involvement is extremely rare in non-Hodgkin's lymphomas. To our knowledge few cases are reported in literature and all of them concern patients with unifocal muscular lymphoid masses usually growing in one of the extremities. Our case-report, instead, regards a 78 years-old woman presenting primary multifocal muscular involvement by extranodal non-Hodgkin's lymphoma (right upper and lower limbs affected at the same time). Therefore, in contrast with the therapeutic approach suggested by other Authors in such neoplasms (radiotherapy or combined radio-chemotherapy), we preferred to administer only chemotherapy. The treatment led to a complete regression of all lymphoid masses. By now the woman is healthy and disease-free as confirmed at the one-year haematological follow-up.

Aged↗
PubMed1996

Hyperhomocysteinemia and deep-vein thrombosis. A case-control study.

In a case-control study, fasting total homocysteinemia was determined in 208 consecutive outpatients who underwent phlebography because of the first episode of clinically suspected deep-vein thrombosis (DVT) of lower limbs. Contrast venography confirmed the clinical suspicion in 60 patients (28.8%). Hyperhomocysteinemia was detected in 15 of the 60 patients with DVT (25.0%), and in 17 of the 148 subjects without thrombosis (11.5%; p = 0.025). The OR for having an acute DVT in patients with hyperhomocysteinemia was 2.6 (95% CI: 1.1-5.9). It is concluded that high plasma homocysteine levels are significantly associated with DVT in symptomatic patients. Further studies are needed to clarify the clinical implications of this association.

Adult↗
PubMed1995

Parkinson's disease affects automatic and spares intentional verbal learning. A stochastic approach to explicit learning processes.

We studied word list and paired associates learning in patients with idiopathic Parkinson's disease and normal controls by means of a two-stage stochastic model, which allows independent measurements of encoding, storage and retrieval abilities. We preliminarily ascertained that the model components were both sufficient and necessary to account for the overall performance of the subjects, and then compared the learning abilities between the two groups. Parkinson's disease patients were selectively impaired in identifying well-known engrams, for which learning is superfluous, and in automatic retrieval, namely in abilities that do not need attentional effort. By contrast, they were unimpaired in encoding and intentional retrieval, which require a purposeful effort. The automatic-voluntary dissociation of Parkinson's disease patients' motor behaviour is, therefore, paralleled by some features of their memory performance.

Aged↗
PubMed1995

Intracranial meningiomas in the 9th decade of life: a retrospective study of 17 surgical cases.

The general availability of cerebral computed tomographic and magnetic resonance imaging scans makes the observation of symptomatic intracranial meningiomas in very elderly patients (aged 80 yr or more) relatively frequent. A few authors have reported on patients who have undergone surgery for intracranial meningiomas in their 9th decade of life, without providing indications regarding the surgical criteria and the prognostic factors. We report on a series of 17 patients who have received surgery for intracranial meningiomas in their 9th decade of life, with the goal of determining some surgical criteria for general physicians and neurosurgeons. Patients with severe systemic disease and definite functional limitations (American Society of Anesthesiology Class III) had a major postoperative morbidity (P = 0.020) and mortality (P = 0.005), especially if they scored low (< 70) on the preoperative Karnofsky Rating Scale (P = 0.010). The risk of postoperative morbidity was higher when the maximum diameter of the tumor was > 5 cm (P = 0.031).

Aged↗
PubMed1995

[The neuroglycopenic syndrome due to insulinoma. A clinical case report].

The authors report a case of a woman affected by pancreatic insulinoma who had been suffering from recurrent and misdiagnosed hypoglycemic attacks since 3 years. The total loss of warning neurogenic symptoms replaced by sudden onset of neuroglycopenic symptoms had delayed the proper and early diagnosis because of repeated and useless cardiovascular and neurological investigations. Moreover, it is stressed how difficult is to reveal such neoplasia that, despite the severe symptoms, are usually small in size and often undetectable even with TC scan. Therefore, when clinical pattern is strongly suggestive for insulinoma the use of invasive angiography or other techniques is mandatory and often conclusive. Actually clinical data have the priority in whole diagnostic pathway.

Chronic Disease↗
PubMed1994

N-acetylaspartylglutamate selectively inhibits neuronal responses to N-methyl-D-aspartic acid in vitro.

Canavan's disease is an autosomal recessive disorder characterized by a deficiency of aspartoacylase and accumulation of N-acetylaspartic acid (NAA), leading to a severe leukodystrophy and spongy degeneration of the brain. N-Acetylaspartylglutamate (NAAG), the presumed product of NAA, also accumulates in this disease. The endogenous dipeptide NAAG has been suggested to have low potency at NMDA receptors. Here we have tested the actions of NAAG and NAA on NMDA-evoked responses in cultured cerebellar granule cells. In differentiating granule cells grown in low-K+ medium, NAAG negated the survival-promoting effects of NMDA but not K+ depolarization. Neither NAAG nor NAA alone promoted cell survival in low-K+ medium. The modest trophic action of 50 microM kainic acid in low-K+ medium was reinforced by the NMDA receptor antagonist dizocilpine maleate and by NAAG. In K(+)-differentiated granule cells, NAAG raised the threshold of NMDA neurotoxicity but not that of kainate. The observed activities of NAAG were overcome by excess NMDA and were not mimicked by NAA. These data raise the possibility that disruption of NMDA receptor processes by NAAG may be of pathophysiological relevance.

Animals↗
PubMed1994

[Immunological indices in myelodysplastic syndromes].

Several studies aiming to describe the immunological abnormalities occurring in patients affected by myelodysplastic syndromes (MDS) have been carried out in recent years. We report on the immunological abnormalities found in 22 myelodysplastic patients at the time of diagnosis (RA: 2 cases; ASIA: 4 cases; AREB: 6 cases; AREB-T: 6 cases. LMMC: 4 cases). Matched with similarly aged healthy people (controls) all our patients revealed a significant lymphocytopenia mainly due to a reduction both in number and percentage of T-helper series with decreased OK T4/OK T8 ratio as a result; even B-cells were reduced in number but their percentage still overlapped with the controls. Out of 22 patients, 13 showed hypergammaglobulinemia (polyclonal in 12 cases, monoclonal in the one left) and 2 read positive for Coomb's and Ana-test respectively. The involvement of T-cell immunity in the course of MDS can be explained if we consider the clonal origin of such diseases. Among myelodysplastic patients the ones affected by LMMC, AREB and AREB-T show the heaviest immunological abnormalities: in these cases the whole of T-cells subsets and NK cells as well are affected. Eventually, the mentioned abnormalities are of paramount importance to explain how easily these patients can develop both severe infectious diseases and abrupt acute leukemia.

Aged↗
PubMed1994

[Temporary aspects of aging: a new approach to the problem].

Medical, psychologic and social problems are typical of the old age. Usually growing old means organic impair, loneliness and a lower social role; moreover, spatial behavior is completely reduced. The period could be lived and be considered in a different way, although aging is unavoidable. This work suggests that we should consider the passing of time a most comprehensive way. The cyclic, biological time can be replaced by a time which considers and gives expression to everybody's needs and activities. The first aim is to give the elderly a new social role, necessary to avoid a "ecosystemic destabilization". Therefore social workers should supply the aged with a new education at "lived time", as a new therapy form.

Aged↗