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Biomedical subjects

M Marini

Publications and source records attributed to M Marini.

At least 109 records · Page 6Linked to original sources
PubMed1996

[Myositis: diagnostic potential of a magnetic resonance unit with low intensity field (0.2 T)].

Magnetic Resonance Imaging (MRI) is a useful tool for demonstrating muscle changes in patients with inflammatory myopathies. We investigated the diagnostic capabilities of low field (0.2 T) MRI with a dedicated coil in a series of patients with an unquestionable clinical diagnosis of inflammatory myopathy. Infiltrating processes or muscle swelling are depicted as low-signal areas on T1-weighted SE images and as high-signal areas on T2-weighted SE and short time inversion recovery (STIR) images. Fatty infiltration appears as a high-signal area within muscles on T1-weighted SE images. T2-weighted SE and STIR sequences are highly sensitive in demonstrating infiltrating processes or muscle swelling. The signal-to-noise ratio was higher on T2-weighted SE than on STIR images; on the other hand, fast STIR sequences can effectively reduce scan times. To conclude, low field MRI is a useful tool in the study of inflammatory myopathies thanks to its noninvasiveness and to the good depiction of muscle inflammation provided by T2-weighted SE and STIR images.

Adult↗
PubMed1996

Computed tomography of bowel wall in patients with Crohn's disease: relationship of inflammatory activity to biological indices.

Bowel wall thickening in Crohn's disease can be demonstrated by Computed Tomography. The aim of this investigation was to correlate different patterns of bowel wall thickening, detected with Computed Tomography, with serological parameters of activity of Crohn's disease. Thirty-eight patients (24 males, 14 females, aged 21 to 62 years) were studied. Patients were divided into 3 groups according to Computed Tomography appearance of bowel wall: 1) homogeneous symmetrical thickening of wall; 2) bowel showing a layer of submucosal low attenuation; 3) scarred narrowing of wall producing stenosis. A patient was considered to have biochemically active disease if at least 2 of the following parameters were abnormal: ESR, C-reactive protein, seromucoids, serum albumin, serum alpha-2 globulin. The first group comprised 20 patients (16 active disease, 4 inactive) and the second group 13 (all inactive); the 2 groups showed a significant difference (Fisher exact test: p < 0.0005) in biological activity. Since only 5 patients belonged to the third group (3 active, 2 inactive disease), no definite conclusion can be drawn on the possible correlation between this Computed Tomography pattern and activity of disease. Results shows a correlation between Computed Tomography patterns of bowel wall disease and biochemical activity of Crohn's disease.

Adult↗
PubMed1995

Bronchial epithelial cells of atopic patients with asthma lack the ability to inactivate allergens.

The cause of asthma is still unknown. Though most asthmatic patients are atopic, only certain atopic subjects develop this disease, and atopic asthmatics recover from asthma after transplantation of lungs from nonasthmatic donors. Thus, there might be a primary local defect in the bronchial wall which affects the expression of asthma in atopic individuals. We show here that the bronchial epithelial cells from atopic patients with asthma are aberrantly permeable to the airborne allergen most often implicated in the pathogenesis of this disease, indicating how it can have access to the antigen-presenting cells (dendritic cells) below the apical surface of the epithelium in vivo. In addition, allergen exposure induces asthmatic epithelial cells to express granulocyte/macrophage colony-stimulating factor, a cytokine involved in the proliferation and function of dendritic cells.

Allergens↗
PubMed1995

Mast cell chemotactic activity of RANTES.

RANTES is a cytokine produced by activated T-lymphocytes that has been shown to exert chemotactic activity for memory-type CD4 T-lymphocytes and eosinophils. In this study, RANTES caused directional migration of human mast cells. When compared to other potential chemoattractants of the same cells, RANTES was found to be more potent than fibronectin and the c-kit receptor ligand, on a molar basis. This cytokine may be a common mechanism in allergic reactions which culminate in the selective migration of memory CD4 T-lymphocytes, eosinophils and mast cells at the tissue site. Asthma and allergic rhinitis may represent possible clinical examples.

Chemokine CCL5↗
PubMed1995

Acoustic neuroma in the pregnant patient.

We report the case history of a 24-year-old woman with an acoustic neuroma diagnosed during the 24th week of pregnancy. Diagnostic steps and surgical management of this uncommon condition, which represents a therapeutic challenge, are discussed.

Adult↗
PubMed1995

Enzymes and inhibitors in leu-enkephalin in metabolism in human plasma.

The enzymes degrading leucine enkephalin in human plasma and the inhibitors active on these enzymes were studied by kinetic and chromatographic techniques. Data obtained evidence the existence of complex kinetics of leu-enkephalin hydrolysis and of formation of its hydrolysis by-products. These appear to originate from the combined effect of further hydrolysis of the enkephalin's fragments after their release and of competition between the different enzymes present in plasma. Chromatographic separation of plasma proteolysis inhibitors indicates the existence of several pools of substances acting on all three enzyme groups that degrade leu-enkephalin. The partial specificity of these substances induces competition effects: consequently, the actual protection over leu-enkephalin is considerably lower that the total inhibitory activity. That notwithstanding, plasma inhibitors control enkephalin hydrolysis to a relevant extent, while they modify only slightly the ratio of hydrolysis between the different enzymes. This latter parameter--and specifically the large prevalence of aminopeptidases over dipeptidylaminopeptidases and dipeptidylcarboxypeptidases--appears controlled mainly by kinetic factors.

Amino Acid Sequence↗
PubMed1995

Long-term follow-up of low-dose methotrexate therapy in one case of idiopathic retroperitoneal fibrosis.

Idiopathic retroperitoneal fibrosis (RPF) is characterized by the development of a fibrotic mass surrounding the abdominal aorta and its branches, of unknown aetiology. Several immunological mechanisms can be operative in the pathogenesis of RPF. Based on this assumption we treated a patient affected by idiopathic RPF with low-dose methotrexate (MTX) therapy. To our knowledge this is the first example of the effectiveness and safety of a long-term low-dose MTX treatment in the post-surgical management of RPF.

Adult↗
PubMed1995

MR imaging in inferior vena cava thrombosis.

PURPOSE: To prospectively evaluate the efficacy of MR imaging in inferior vena cava (IVC) thrombosis; to differentiate acute from non-acute thrombus, and to identify the presence of changes in the morphology and signal intensity during medical treatment. METHODS AND MATERIALS: Seventeen patients with suspected IVC thrombosis underwent 30 MR examinations. The IVC thromboses were subdivided into two groups (acute and non-acute) according to onset of clinical symptoms. MR imaging of the IVC was analyzed and when an IVC thrombus was identified, a qualitative and quantitative assessment of the thrombus on spin-echo sequences with magnitude and phase reconstruction was performed to evaluate the relationship between signal intensity and the time elapse since the onset of clinical symptoms. Venography and/or CT scan proof was available in all cases. RESULTS: IVC thrombus was correctly identified in 19 MR examinations which showed the size, localization and the degree of lysis during follow-up. No differences were found in the signal intensity of the thrombus related to time. The pattern of the signal intensity was homogeneous in six (86%) acute thrombus and heterogeneous in nine (75%) thrombus of more than 1 week duration. A significant statistical relationship (P < 0.01) existed between the thrombus age and differences in the pattern of signal intensity. CONCLUSIONS: MR imaging is accurate to assess the localization and size of IVC thrombus, similar to the imaging techniques of reference. In addition, MR also provides useful information about the age and the morphological variations of thrombus during medical treatment.

Acute Disease↗
PubMed1995

Constitutive expression of endothelin in bronchial epithelial cells of patients with symptomatic and asymptomatic asthma and modulation by histamine and interleukin-1.

BACKGROUND: An upregulation of endothelin-1 expression occurs in bronchial epithelial cells of asthmatic patients. This peptide may mediate bronchoconstriction in asthma, but the mechanisms that modulate endothelin-I synthesis and release are unknown. OBJECTIVE: This study was done to compare the pattern of endothelin-1 expression in patients with symptomatic and asymptomatic asthma and evaluate the ability of inflammatory factors to upregulate endothelin-1 synthesis and release in the epithelial cells of subjects who are free of symptoms. METHODS: Two groups of 10 asthmatic patients were selected. One group had symptomatic asthma with airflow obstruction and moderately to severely increased airway responsiveness. The second group was free of symptoms: they did not show airflow obstruction, and airway responsiveness was borderline or slightly increased. Bronchial biopsy specimens were obtained by means of bronchoscopy and used for immunohistochemical evaluation, epithelial cell isolation, and stimulation experiments with interleukin-1 and histamine. RESULTS: Endothelin-1 immunoreactivity was detected in vivo in the bronchial epithelial cells of all the patients with symptoms and in only two subjects without current symptoms. Incubation of bronchial epithelial cells from patients with asymptomatic asthma with interleukin-1 or histamine, for 8 to 24 hours, resulted in increased expression of endothelin-1 messenger RNA and release of appreciable amounts of the peptide to the culture medium. Those effects were dose- and time-dependent. Histamine and interleukin-1 were effective at concentrations similar to those detected in the bronchoalveolar lavage of patients with symptomatic asthma. CONCLUSION: Endothelin-expression is upregulated in bronchial epithelial cells of asthmatic patients with symptoms and evidence of functional derangement as compared with patients without symptoms and airflow obstruction. Exposure of cells from patients with asymptomatic asthma to factors that are released during acute exacerbation of the disease induces endothelin synthesis and release.

Adolescent↗
PubMed1995

Factors influencing the low density lipoprotein profile in type 2 diabetic patients.

The lipoprotein distribution profile was examined in Type 2 (non-insulin-dependent) diabetic patients (n = 52), with particular emphasis on factors influencing low density lipoproteins (LDL). Triglycerides were negatively correlated with LDL-2 (r = 0.34, p < 0.05) and positively correlated with smaller, denser LDL-3 (r = 0.57, p < 0.001). This yielded a highly significant, negative correlation between triglycerides and the LDL-2/LDL-3 mass ratio (r = -0.59, p < 0.001) which is an indication of the presence of smaller LDL particles. Parameters of glycaemic control, in the form of fasting blood sugar and glycated haemoglobin (HbA1c), were also negatively correlated with the LDL-2/LDL-3 mass ratio in univariate analyses; both remained significantly correlated with the mass ratio when corrected for triglycerides. Stepwise multiple regression analysis identified a three-parameter model comprising triglycerides, HbA1c, and high density lipoprotein cholesterol as best defining the variations in the LDL-2/LDL-3 mass ratio (adjusted r2 = 0.52). These observations are consistent with an independent impact of diabetes on the LDL distribution profile and the possibility that the latter may be subjected to multiple pathological influences in diabetic patients.

Analysis of Variance↗
PubMed1995

[The role of magnetic resonance imaging with a low-intensity field (0.2 T) in assessing expansive lesions of the hand and wrist].

The diagnostic capabilities of a small-size low-field (0.2-T) MR unit with a dedicated coil were investigated in the study of expansive lesions of the hand and wrist. Twenty-five patients suffering from the following diseases were examined: synovial cyst (6 patients), ganglion cyst (4), acute suppurative tenosynovitis (3), stenosing tenosynovitis (2), arteriovenous fistula (1), lipoma (1), fibrolipoma (2), chondroma (1), glomus tumor (1), fibromatosis palmaris (3), villonodular synovitis (1). Spin Echo (SE) and Gradient Echo (GE) scans were performed on all patients. The MR findings were compared with US, surgical and pathologic results. In synovial and ganglion cysts, acute suppurative and stenosing tenosynovitis, fibromatosis palmaris, fibrolipoma and lipoma, MRI showed typical patterns. In arteriovenous fistula, chondroma, glomus tumor and villonodular tenosynovitis, an accurate diagnosis could not be made: in these cases US failed to yield unquestionable results and the lesions could be diagnosed only at pathology. MRI yielded very accurate information as to lesion site and relationship with the surrounding structures; this kind of information, which is extremely important for the surgical approach, is not always provided by US. Low-field MRI can be considered a valuable diagnostic tool in the study of some expansive lesions of the hand and wrist. In other lesions this method can play a major role for both their characterization and the surgical approach.

Adolescent↗
PubMed1995

[Prognostic value of ECG changes detected by Holter monitoring in silent ischemic heart disease in the aged].

Ischemic Cardiomiopathy (IC) is the main cause of morbidity and mortality in the elderly and its incidence increases progressively with age. Holter monitoring (HM) is used to study IC which reveals asymptomatic ischemic episodes identifiable with the depression of the ST tract. It has been demonstrated that these electric manifestations have the same unfavourable diagnostic value as those accompanied by pain. In order to evaluate the prevalence and prognostic significance of episodes of silent myocardial ischemia in the elderly patient, we examined 99 consecutive patients with stable clinical symptoms of myocardial ischemia and a positive ergometric test (ET). The patients were randomly divided according to age (< or = 65 years, >65 years) into two groups with homogeneous clinical feature, except for a higher prevalence of women in the second group. The HM analysis, carried out for 24 hours during common every day activities and after suspending anti-ischemic therapy, showed that 62 patients (63%) had 289 episodes of electric ischemia; 216 (75%) of these were asymptomatic, and, in the group of elderly there was a higher incidence of ST depression unaccompanied by pain (A vs B = 86 vs 132 episodes, p < 0.001). Comparing the patients with and without anamnestic evidence of myocardial infarction it was found that the first group presented a higher prevalence of ST depression both asymptomatic and symptomatic (147 vs 71 silent episodes, p < 0.001, and 49 vs 24 symptomatic episodes, p = 0.015 respectively), while no statistically significant differences were found between the two age groups. Electric alterations of the asymptomatic ischemic kind were more often found in subjects with stable angina, above all if elderly; this is important from a prognostic point of view as few elderly patients are capable of performing a maximal TE and it is thus significant of reduced coronary reserve. From our data we observed that in patients with stable angina, especially if elderly, Holter revealed asymptomatic ST depression analyzed considering both its length and magnitude, is able to give prognostic evidence of subsequent coronary events.

Age Factors↗
PubMed1995

In the search for new antiinflammatory drugs: synthesis and antiinflammatory activity of some Thiazolo(3,2-a)pyrimidine derivatives containing a thioether group.

Our strategy for the exploration of new NSAIDs starts on the synthesis of derivatives of 5-oxo-5H-Thiazolo [3,2-a] pyrimidines. The compounds were achieved by the following methods: (a) condensation of 2-amino-4-alkylthiomethilthiazole with ethyl 4-chloro-3-oxobutanoate (PPA method), (b) triphenyl phosphonium salts preparation, (c) Wittig-reaction of the salts with suitable aldehyde. Synthesized compounds were screened for antiinflammatory activity in the carrageenin rat paw oedema assay according to Winter et al. Some of the new synthesize compounds, at the dose used (50 mg/Kg) reduced meaningfully the oedema. The pharmacological effect varies according to the administration time.

Alkylation↗
PubMed1994

Effect of differentiation on hydrolysis and association of Leu-enkephalin to K562(S) cells.

Hydrolysis of Leu-enkephalin and association to cells of the peptide-radioactive label have been studied on the K562(S) erythroleukemic cell subline. Data obtained indicate that in the presence of these cells, Leu-enkephalin is hydrolyzed, that the peptide's radioactive label is partially associated to cells, and that these phenomena are related. Hydrolysis and association are inversely modified by the cells' differentiation: hydrolysis is increased and association is decreased in differentiated compared with nondifferentiated cells. Moreover, the ratio of hydrolysis by-products is dissimilar between differentiated and nondifferentiated cells as a result of a significant modification of the soluble enzymes' release. The alterations induced by differentiation on all parameters investigated seem to indicate significant changes in the membrane structures responsible for the mechanisms controlling these phenomena.

Amino Acid Sequence↗
PubMed1994

Detection of cytokines and their cell sources in bronchial biopsy specimens from asthmatic patients. Relationship to atopic status, symptoms, and level of airway hyperresponsiveness.

This study evaluated immunoreactivity for several cytokines in bronchial tissue of asthmatic patients and related this to the clinical and functional characteristics. Patients were allocated into two different groups on the basis of their atopic status (atopic and nonatopic), with two subgroups of symptomatic and asymptomatic subjects in each. Five healthy volunteers were tested as control subjects. After clinical and functional assessment, all of the subjects underwent bronchoscopy. Several biopsy specimens were obtained for immunohistochemical and immunoelectron microscopic evaluation. Symptomatic asthmatic subjects had increased expression of immunoreactive interleukin (IL) 1 beta, IL-2, IL-3, IL-5, granulocyte-macrophage colony-stimulating factor (GM-CSF), and tumor necrosis factor alpha (TNF alpha) when compared to the asymptomatic patients or normal control subjects. The cell sources of IL-1 beta were monocytes and dendritic cells in atopic patients and monocytes alone in nonatopic asthmatic subjects. The CD4+ T lymphocytes from atopic asthmatic subjects predominantly expressed IL-3, IL-4, IL-5, and GM-CSF immunoreactivity, whereas CD4+ T cells from nonatopic patients predominantly expressed IL-2, IL-3, and IL-5, and GM-CSF immunoreactivity. Mast cells showed immunoreactivity for TNF alpha, IL-3, IL-5, and GM-CSF. Immunostaining for TNF alpha and GM-CSF was also detected in bronchial epithelial cells and monocytes. Tissue eosinophilia and the level of airway hyperresponsiveness more closely correlated with IL-5 immunoreactivity in atopic asthmatic subjects and with IL-2 and GM-CSF immunoreactivity in nonatopic patients.

Adult↗
PubMed1994

[Blood gastrin and colorectal neoplasms].

Gastrin has a trophic effect on the mucosa of the gastrointestinal tract and seems to have the potential for promoting colonic cancerogenesis through a chronic stimulation of the epithelial proliferation. Plasma gastrin has been reported to be elevated in patients with colorectal neoplasms. The aim of the present study was to verify this observation. Presurgical serum levels of gastrin were compared between 49 patients with colorectal neoplasms and 47 controls hospitalized for other surgical lesions. Results show significantly higher gastrin levels of case group than controls: 72.72 + 85.41 vs. 46.79 + 24.09 pg/ml (p < 0.05), and provide support for the hypothesis of a gastrin-stimulated neoplastic growth enhancing at the same time the potential therapeutic role of reducing gastrin secretion.

Adenoma↗