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C Filippi

Publications and source records attributed to C Filippi.

At least 37 records · Page 2Linked to original sources
PubMed1996

Uncoupling effect of polyunsaturated fatty acid deficiency in isolated rat hepatocytes:effect on glycerol metabolism.

The effects of a 4-week deficiency in polyunsaturated fatty acids (PUFA) in isolated rat hepatocytes have been investigated for oxidative phosphorylation and fatty acid, dihydroxyacetone (DHA) or glycerol metabolism. Oxygen uptake was significantly increased (by 20%) with or without fatty acid addition (octanoate or oleate) in the PUFA-deficient group compared with controls. The effect persisted after oligomycin addition but not after that of potassium cyanide, leading to the conclusion that, in these intact cells, the mitochondria were uncoupled. The PUFA-deficient group exhibited a significant decrease in the cytosolic ATP/ADP ratio, whereas the mitochondrial ratio was not affected. PUFA deficiency led to a 16% decrease in DHA metabolism owing to a 34% decrease in glycerol kinase activity; the significant decrease in the ATP/ADP ratio was accompanied by an increase in the fractional glycolytic flux. In contrast, glycerol metabolism was significantly enhanced in the PUFA-deficient group. The role of the glycerol 3-phosphate dehydrogenase step in this stimulation was evidenced in hepatocytes perifused with glycerol and octanoate in the presence of increased concentrations of 2,4-dinitrophenol (Dnp): uncoupling with Dnp led to an enhancement of glycerol metabolism, as found in PUFA deficiency, although it was more pronounced than in controls. The matrix/cytosol gradients for redox potential and ATP/ADP ratio were lower in cells from PUFA-deficient rats, suggesting a decreased mitochondrial membrane potential in accordance with the uncoupling effect. Moreover, a doubling of the mitochondrial glycerol 3-phosphate dehydrogenase activity in the PUFA-deficient group compared with controls led us to conclude that the activation of glycerol metabolism is the consequence of two mitochondrial effects: uncoupling and an increase in glycerol 3-phosphate dehydrogenase activity.

Adenosine Diphosphate↗
PubMed1994

Effects of the antimycotic molecule Iturin A2, secreted by Bacillus subtilis strain M51, on arbuscular mycorrhizal fungi.

A new system, devised for the study of early stages of arbuscular mycorrhizal infection, was used to test the effect of the biological control agent Iturin A2, secreted by the strain M51 of Bacillus subtilis, on the development of arbuscular mycorrhizal fungi. The saprophytic growth of the fungus Glomus mosseae was inhibited by Iturin A2 concentrations higher than 100 micrograms/g of sand; whereas, in the presence of the tomato host plant, both, pre-infection events and intraradical growth were not negatively influenced by the antifungal compound; furthermore, the development of arbuscular mycorrhizal symbiosis was not impeded by the biocontrol agent in field conditions, while Fusarium oxysporum f. sp. lycopersici infection was hindered.

Anti-Bacterial Agents↗
PubMed1994

Acute hypertensive encephalopathy: findings on spin-echo and gradient-echo MR imaging.

OBJECTIVE: The purpose of this study was to investigate the findings on spin-echo and gradient-echo MR images obtained in patients with hypertensive encephalopathy. SUBJECTS AND METHODS: The MR images of 36 patients with clinically documented acute (< 72 hr) hypertensive encephalopathy were prospectively examined. Brain swelling on short TR images, hyperintensity on long TR images, and hypointensity on long TR and gradient-echo images were assessed. RESULTS: The most common finding was hyperintensity in the supratentorial white matter (n = 32), representing hypertensive encephalopathy-induced reversible edema, irreversible infarction, or preexisting ischemic disease. These entities were difficult to distinguish on the basis of the initial examination. A more characteristic finding was edema (swelling on short TR images and hyperintensity on long TR images) in the basal ganglia (n = 22), brainstem (n = 15), and cerebellum (n = 11). Punctate foci of hypointensity, seen on long TR spin-echo images but optimally visualized on gradient-echo images, were the most distinguishing feature of this disorder. CONCLUSION: MR imaging is efficacious in revealing deep ganglionic and posterior fossa edema, which is characteristic of hypertensive encephalopathy. Serial MR studies are necessary to distinguish transient edema from permanent zones of infarction. Gradient-echo MR imaging is particularly valuable in visualizing petechial hemorrhages, the presence of which distinguishes nonspecific white matter disease from an acute or prior episode of hypertensive encephalopathy and serves as a permanent marker of this disease.

Adolescent↗
PubMed1993

[Dyslipidemia in obesity: pathogenetic considerations and our experience].

The prevalence of obesity is increasing today in western industrialized countries: therefore, many authors are focusing their attention on its multiple endocrine and metabolic effects. Because of the pathogenetic linkage between obesity and dyslipidemia, we have studied serum lipid pattern in a group of obese women: HDL-Cholesterol (HDL-C) deficiency was the most striking lipoproteinemic disorder. This fact points out, in our opinion, that obesity must be considered as a risk factor for cardiovascular disease.

Adult↗
PubMed1991

[X-ray computed tomography or MRI in the assessment of bone tumor extension].

Conservative surgery of primary bone tumors, which has become possible owing to the progress made by chemotherapy, must be carcinological, and it is therefore based on a thorough assessment of local tumor extension. CT and MRI have proven their great value for this assessment. While CT clearly shows the calcified tissue and the extension into soft tissue, MRI is more effective to delineate the tumoral and intraosseous margins and, more importantly, for the exploration within bone, for which it has the advantage of making a study in all planes possible. The anatomical substrate and exact meaning of the MR signal of pathological tissue still remains to be specified. However, MRI already appears to be the essential examination for the assessment of local bone tumor extension. If it did not have contraindications, it could replace CT within the next few years.

Adolescent↗
PubMed1991

[Reiter's syndrome. Description of 2 cases with Chlamydia trachomatis infection].

Two cases of Reiter's syndrome that followed chlamydial infection are reported. The presence of ocular and genitourinary symptoms that suggest Reiter's disease is common, as the presence of histocompatibility antigen HLA B 27. Both cases had a particularly favourable course. The peculiar persistence of IgA anti-Chlamydia antibodies for relatively long periods of time induce the Authors to advance a hypothesis of use in chronic chlamydial infection diagnosis.

Adult↗
PubMed1990

CD4+:neopterin ratio correlates with p24 antigenaemia in HIV infected patients.

In an effort to improve the Walter Reed Staging System (WR), which mainly relies on immune depletion parameters, by introducing viral replication and T-cell activation markers, we examined by p24 antigenaemia and serum neopterin levels (SNL) 72 HIV positive PGL, ARC and AIDS patients (11 of whom classified as WR 2, 21 as WR 3, 16 as WR 5 and 24 as WR 6). While CD4 cell counts, already weakly correlating with the WR itself, did not significantly differ between p24 antigen (p24 AG) positive and negative patients, striking differences between the two groups, especially in PGL patients (p less than 0.0001), were found as far as SNL was concerned. In fact, SNL values, fluctuating around 10 and 30 nmol/l, respectively, in p24 Ag positive and negative patients regardless of their WR allocation, seemed rather to reflect, as global means of any given class, prevalence rate of p24 Ag positivity. We suggest, therefore, to use CD4/SNL ratio (R) for HIV infection and disease staging, as it not only may represent a compromise index between cellular immune depletion and T-cell activation, but also seems to take into account the viral replication component, already shown to be an important predictive marker of disease progression.

AIDS-Related Complex↗
PubMed1990

Behaviour of different clinical, immunological and serological parameters observed in a group of HIV positive patients during a 12 month treatment period with zidovudine.

During a 12 month open clinical trial, 14 patients (6 with AIDS, 2 with ARC and 6 with PGL) were continuously administered a daily 1200 mg dose of Zidovudine. Clinical course was correlated with a number of serological (HIV p24 antigen, p17 and p24 antibodies) and immunological (CD4 cell counts, serum neopterin and beta 2-microglobulin levels) parameters. All patients survived until the end of the trial: none developed major opportunistic infections, but 5 required an average of 7 blood transfusions each. Disappearance of p24 Ag was observed in 4 out of 7 patients, although with a subsequent reappearance in 3; moreover, changes of p24 Ag and HIV core Ab profiles were generally paralleled by neopterin and, to a lesser extent, by CD4/neopterin ratio variations. In the long run, significant differences between baseline and end-point results were shown by neopterin, but not by CD4 cell counts and beta 2-microglobulin levels. Efficacy of Zidovudine therapy seemed to be mainly related to clinical, but even more so, to immunological and serological status at baseline; in fact, severe clinical deterioration was observed in 2 patients who had an already low CD4/neopterin ratio from the beginning, coupled with a p24 Ag positivity and a negativity of both anti-p17 and -p24. Conversely, a stable clinical condition was observed in those patients in whom the reverse was true.

AIDS-Related Complex↗
PubMed1990

[Primary amyloidosis. A case report].

Primary amyloidosis is an uncommon disease which can be considered a diagnostic challenge. A recently observed case, initially characterized by peripheral neuropathy and subsequently by heart failure and sudden death, is described.

Aged↗
PubMed1988

[Multifocal fractures of the mandibular symphysis. Apropos of 3 cases].

Three patients presented with multiple site fractures of mandibular symphysis, associated in two cases with a bilateral subcondylar fracture. Treatment was by multiple solid osteosynthesis of mandibular body combining miniaturized screw plates and steel wire osteosynthesis. Emphasis is placed on the interest of a stable solid osteosynthesis of mandibular symphysis by screw plate, combined with osteosynthesis using a steel wire passing through the hole of a plate and into the small basilar bone fragment, allowing in this way the restitution of a perfect morphology of symphysis.

Adolescent↗
PubMed1982

[Doppler velocimetric evaluation of the reliability of Allen's test for radial artery catheterization].

The result of Allen's test was compared with the variations in the Doppler flow recording of the thumb artery after compression of the radial artery in 76 volunteers. In five cases, manual compression let to a disappearance systolic flow, showing an absence of collateral ulnar circulation. In fifteen cases, the systolic flow was greatly reduced in the thumb. It is interesting to find that 14.6 per cent of the subjects have their two hands in a different classification (asymmetric subjects). In 99.34 per cent of the cases the results of these two methods was the same. The routine use of Allen's test before radial artery catheterization is fully justified by these results.

Adolescent↗
PubMedDate not supplied

Detection of hemorrhage in acute cerebral infarction. Evaluation with spin-echo and gradient-echo MRI.

We investigated the efficacy of magnetic resonance imaging (MRI) in the detection and delineation of acute hemorrhagic cerebral infarction and evaluated the role of gradient-echo imaging in these patients. This study was performed prospectively. Entry criteria were: (1) Clinical evidence of acute supratentorial infarction later confirmed by at least one imaging study, and (2) unenhanced computed tomography (CT) and MRI scans performed within 72 hours of ictus. The first 50 patients who met these criteria were included. Comparison of CT and spin-echo (SE) and gradient-echo (GE) MRI at 0.6 T for the visualization of infarction and for the detection or exclusion of hemorrhage were done. There were no cases in which CT was superior to MRI for the diagnosis of either bland or hemorrhagic infarction. All 50 infarcts were detected on long TR SE MRI and 30/50 on GE scans. Eighteen infarcts were judged to be hemorrhagic on the basis of well-established CT and MRI criteria. In all these cases, hemorrhage was most obvious on GE scans as focal areas of marked hypointensity, including 10 cases in which SE MRI and CT demonstrated subtle, equivocal, or no evidence of hemorrhage. In addition, GE MRI allowed for the exclusion of hemorrhage in five cases with equivocal findings of hemorrhage on long TR SE MRI. GE MRI is a valuable adjunct to SE sequences for the detection or exclusion of hemorrhage in acute infarcts with equivocal or mild intensity changes on SE MRI. With further improvements in fast-scanning techniques and a greater understanding of the pathophysiology and clinical implications of hemorrhagic infarction, it may be possible to replace CT with a combination of SE and GE MRI as the primary imaging modality in the evaluation of acute infarction.

Acute Disease↗