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M Felaco

Publications and source records attributed to M Felaco.

At least 37 records · Page 2Linked to original sources
PubMed1997

Massive infiltration of basophilic cells in inflamed tissue after injection of RANTES.

Regulated upon activation normal T expressed and secreted (RANTES) is a new inducible protein member of the human C-C branch of chemokines. RANTES is a potent monocyte and lymphocyte chemoattractant and is a mediator of inflammatory responses. In these studies we found that RANTES 10 ng/50 microl chemoattracts basophilic cells in a dose-dependent manner 4 h after an intradermal injection in rat skin sites, as revealed by optic microscopy. Moreover, in biopsy specimens from rat skin injection sites histamine release was significantly higher (P < 0.05) than in controls (PBS 50 microl) after 4 h from RANTES treatment. The presence of basophilic cells in rat skin injection sites after RANTES-treatment was also confirmed by electron microscopy studies. In addition, histidine decarboxylase (HDC) mRNA was increased in rat skin sites injected with RANTES compared to sites injected with PBS (controls). Our report describes additional biological activities for RANTES, suggesting that this human chemoattractant protein may play a fundamental role in histamine and HDC generation, along with basophilic cell recruitment.

Animals↗
PubMed1996

Vanadate as factor of cardiovascular regulation by interactions with the catecholamine and nitric oxide systems.

The effects of 1 microgram/mL of vanadium, given for 12 mo as sodium metavanadate in drinking water, on cardiovascular and biochemical indices of male rabbits were investigated. At the end of the exposure period, vanadium was more accumulated in bones and kidneys than in spleen and liver; the cardiac ventricles and the aorta contained similar amounts of this element. Blood pressure and heart rate were unchanged in the vanadate-exposed animals since the observed decrease of both cardiac inotropism and stroke volume was counteracted by an increase of peripheral vascular resistance, with reduction of arterial blood flow. The arterial levels of sodium, potassium and aldosterone were unmodified by vanadate which, however, strongly raised those of noradrenaline, adrenaline, L-DOPA, and dopamine. Vanadate caused a marked increase of the activity of monoamine oxidase in renal tubules and liver (probably in relation to the increased plasma catecholamine levels) and a reduction of that of glucose-6-phosphate dehydrogenase in the kidney. There was also evidence that vanadium reduces synthesis and/or release of nitric oxide, the endothelium-derived vasodilating factor, likely through a reduced formation from bradykinin. It was concluded that vanadium may represent an environmental factor of altered cardiovascular homeostasis.

Animals↗
PubMed1994

Renal toxicity and arterial hypertension in rats chronically exposed to vanadate.

The effects of 1, 10, or 40 micrograms/ml of vanadium, given for six or seven months as sodium metavanadate in drinking water on cardiovascular and biochemical variables and the electrolyte metabolism of male Sprague-Dawley rats were investigated. At the end of the exposure period, all animals exposed to vanadate had increased systolic and diastolic blood pressure. This effect was not dose dependent and heart rate and cardiac inotropism were not affected. The role of defective renal function and electrolyte metabolism in such effects was supported, in the rats exposed to 10 and 40 ppm of vanadium, by the following changes: (a) decreased Na, + K(+)-ATPase activity in the distal tubules of nephrons; (b) increased urinary excretion of potassium; (c) increase in plasma renin activity and urinary kallikrein, kininase I, and kininase II activities; (d) increased plasma aldosterone (only in the rats treated with 10 ppm of vanadium). The alterations in the rats exposed to 1 ppm of vanadium were: (a) reduced urinary calcium excretion; (b) reduced urinary kallikrein activity; (c) reduced plasma aldosterone. These results suggest that blood hypertension in rats exposed to vanadate depends on specific mechanisms of renal toxicity related to the levels of exposure.

Animals↗
PubMed1993

Human recombinant interleukin-1 receptor antagonist (hrIL-1RA) inhibits prostaglandin E2 (PGE2) generation but not alkaline phosphatase activity in in vivo chronic granulomatous tissue induced by KMnO4.

Interleukin-1, a soluble polypeptide, plays an important role in inflammatory reactions by increasing prostaglandin E2 (PGE2) generation. Human recombinant IL-1 receptor antagonist (hrIL-1ra) is a natural inhibitor of IL-1 which blocks its activity in several inflammatory states. In these studies we found that hrIL-1ra (250 mg/ml) inhibits the generation of PGE2, as measured by RIA method, in minced mouse granuloma tissue (700 mg) treated overnight with LPS (10-1000 ng/ml) or hrIL-1 beta (0.1-10 ng/ml). In addition, we show that hrIL-1ra (250 ng/ml) strongly inhibited IL-1 alpha and IL-1 beta, as measured by ELISA method, in the minced granuloma tissue treated overnight with LPS 1 micrograms/ml or IL-1 beta (10 ng/ml). The granuloma tissue induced in mice by a dorsal subcutaneous injection (0.2 ml) of a saturated solution (1:40 dilution) of KMnO4 crystals, presented an alkaline phosphatase activity which was not inhibited by two intraperitoneal administrations of hrIL-1ra 20 micrograms/200 ml bolus injections (given at the same time as KMnO4 injection and one 24 h later). These results show for the first time that hrIL-1ra blocks PGE2, IL-1 alpha and IL-1 beta but not alkaline phosphatase activity, which is a marker in growing bone and in calcific and inflamed tissue.

Alkaline Phosphatase↗
PubMed1992

Renal mechanisms in the cardiovascular effects of chronic exposure to inorganic mercury in rats.

Male weanling Wistar rats received 200 micrograms/ml of mercury (Hg), as HgCl2, in drinking water for 180 days. At the end of the treatment, systemic arterial blood pressure was augmented, cardiac inotropism was reduced, and heart rate was unchanged. Light and electron microscopical studies of the kidney showed a mesangial proliferative glomerulonephritis in about 80% of the glomeruli. Tubular cells showed reduction of the acid phosphatase activity, which was related to functional abnormalities of the lysosomes. In the 24 hour urine samples of the Hg exposed rats, there was slight reduction of kallikrein activity, but evident proteinuria was not present in all samples. Plasma renin activity was reduced, that of angiotensin I-converting enzyme was augmented, and plasma aldosterone concentrations were unchanged. Mercury was accumulated mostly in the kidney of the Hg treated animals; and the content of Hg in the heart was higher than in the brain. These data show that chronic exposure to Hg acts on the kidney with complex mechanisms of toxicity; these contribute to modify systemic haemodynamics.

Animals↗
PubMed1991

Glutathione transferase isoenzymes in normal and neoplastic human kidney tissue.

Glutathione transferase (GST) activity in the cytosolic fractions of renal cortex tumour was found to be significantly lower (215 +/- 156 mU/mg) than that present in the corresponding non-tumour (466 +/- 278 mU/mg) tissues. Using the immunoblotting technique, glutathione transferase isoenzymes expression in both tumour and non-tumour kidney was investigated. Alpha and pi class glutathione transferases were the most abundant enzymes in non-tumour kidney and were expressed by all samples investigated. Immunofluorescence analysis indicated that the pi class enzymes are localized mainly in the distal convoluted tubules, whereas alpha class enzymes are localized in the proximal tubules. In the tumour moiety the alpha class GST appears to be absent or expressed at low level as compared with non-tumour samples. On the contrary, no significant differences in the expression of pi class GST were found in tumour as compared with non-tumour tissues. Mu class GST protein was detected in 12 of 26 samples tested. When present, mu class GST constitutes a few per cent of total GST protein. Immunofluorescence studies indicate that mu class GSTs are localized within the distal convoluted tubules. According to the electrophoretic mobility at least two different mu GST subunits (26.5 and 27.5 kd) were found. In one sample only the faster mu class GST subunit was present, two samples expressed both types of GST subunits, whereas nine samples expressed only the slower GST subunit. With the exception of one sample, a reduction of mu class GST expression was seen in tumour as compared with non-tumour tissues. The decrease of activity seen in the cytosolic fraction of tumour kidney must be ascribed mainly to a reduction or to a lack of expression of alpha class GST and to a lesser extent of mu class GST.

Adult↗
PubMed1990

Glutathione transferase isoenzymes from human prostate.

By using affinity-chromatography and isoelectric-focusing techniques, several forms of glutathione transferase (GSTs) were resolved from human prostate cytosol. All the three major classes of GST, i.e. Alpha, Mu and Pi, are present in human prostate. However, large inter-individual variation in the qualitative and quantitative expression of different isoenzymes resulted in the samples investigated. The most abundant group of prostate isoenzymes showed acid (pI 4.3-4.7) behaviour and were classified as Pi class GSTs on the basis of their immunological and structural properties. Immunohistochemical staining of Pi class GSTs was prevalently distributed in the epithelial cells surrounding the alveolar lumen. Class Mu GSTs are also expressed, although in small amounts and in a limited number of samples, by human prostate. The major cationic isoenzyme purified from prostate, GST-9.6; (pI 9.6; apparent subunit molecular mass of 28 kDa), appears to be different from the cationic GST alpha-epsilon forms isolated from human liver and kidney as evidenced by its structural, kinetical and immunological properties. This enzyme, which accounts for about 20-30% (on protein basis) of total amount of GSTs, is expressed by only 40% of samples. GST-9.6 has the ability to cross-react in immunoblotting analysis with antisera raised against rat liver GST 2-2, rather than with antisera raised against members of human Alpha, Mu and Pi class GSTs. Although prostate GST-9.6 shows close relationship with the human skin GST pI 9.9, it does not correspond to any other known human GST.

Aged↗
PubMed1989

Glutathione transferase isoenzymes from human testis.

By using affinity chromatography and isoelectric focusing techniques, several forms of glutathione transferase (GSTs) were resolved from human testis obtained from patients operated on for malignant diseases. Large interindividual variations in the expression of different isoenzymes resulted in the samples investigated. Five out of six samples analysed expressed GST-4.4 that resulted in being structurally and immunologically identical to GST-pi (class Pi). All the cationic GSTs of human testis, except for GST-8.36, GST-9.1 and GST-10.1, are homodimers of 24,500 Mr subunit and cross reacted with antisera raised against class Alpha GST. Some of the forms isolated (GST-3.8, GST-8.36, GST-9.1 and GST-10.1) can not apparently be related to any of GSTs so far characterized in other human tissues. Upon SDS/polyacrylamide gel electrophoresis, GST-8.36 and GST-9.1 appeared to be heterodimers of 24,500 and 26,500 Mr subunits and were found only in the testis seminoma suggesting that they might be tumour specific isoenzymes. GST-3.8 appeared to be formed by heterodimers of 23,000 and 26,500 Mr subunits whereas, GST-10.1 was found to be dimers of 22,000 and 24,500 Mr subunits. In addition, the results of immunohistochemical studies with antisera raised against both class Pi and Alpha GSTs are reported.

Aged↗
PubMed1984

[Adjuvant potential of vitamin E in the induction of experimental allergic encephalomyelitis: histological aspects].

In this study we report the effect of Vit. E, as an immunostimulating factor, on the induction of Experimental Allergic Encephalomyelitis in Lewis rat. The animals were inoculated intracutaneously in the plantar areas with emulsion of isologous spinal cord suspensed in Incomplete Freund's Adjuvant (IFI) and Vit. E. Histologic examination revealed the basic lesion of a perivenous cuff of mononuclear cells and small areas of demyelinated axons. The clinical signes are graded in order to the time of induction. It is possible an action of "adjuvanticity" of Vit. E on the various cells involved in the immune response by cell transformation and moltiplication.

Adjuvants, Immunologic↗
PubMed1984

[Clinical and cytogenetic staging of chronic myeloid leukemia. Philadelphia positive].

A cooperative study between clinical and cytogenetic steps in 44 patients with Ph'+ CGL is reported in order to verific the usefulness of the cytogenetic screening for the diagnosis and the right classification of the patients. The study of the clinical steps is carried out on the basis of the parameters suggested by Tura and coll.; in the one of the cytogenetic steps Sandberg classification modified by the Authors is adopted. In 40 cases the comparison shows a marrow correspondence between clinical and cytogenetic steps. In fact the overage survival in the classical true steps of the disease is almost the sance in the 1st and 2nd step. In the 3rd step the survival is strongly reduced meaning that the more chromosome alterations are observed the more survival is reduced.

Adolescent↗
PubMed1981

[Karyotype in chronic myeloid leukemia in a blastic crisis. I. Monosomy 16].

One case of Chronic Granulocytic Leukemia is reported, in which the patient showed, during a blastic crisis, an aneupolid cariotype 45, XX, t (9; 22) (q34; q11), -16. This paper emphasizes the rare involvement of the chromosome 16 in Leukemias, and stresses the high frequency of the alterations of the chromosome group E in the course of blastic crisis.

Chromosome Aberrations↗
PubMed1981

[Karyotype in chronic myeloid leukemia in a blastic crisis. II. Trisomy 17].

One case of a patient with Chronic Granulocytic Leukemia showing a double Ph' together with trisomy 17 during blastic crisis is reported. The Ph' chromosome resulting from a standard translocation of the chromosomes 9 and 22 was present in all the 16 mitoses observed, while the trisomy 17 was found in 15. This case is an additional contribution which demonstrates the presence of the alterations of the chromosome group E during the blastic crisis.

Chromosomes, Human, 16-18↗
PubMed1981

[Cytogenetics in bone marrow transplantations. II. Acute lymphocytic leukemia].

In this we report cytogenetic data concerning two patients with Acute Lymphoblastic Leukemia (ALL), submitted to bone marrow transplantation. In one of two patients the chimere was present while in the other case it was absent, since the donor and the acceptor were of the same sex. However even in the latter case, the cytogenetic analysis was useful and led to the identification of endomitosis and endoreduplication phenomena, which are signs for an unlucky prognosis.

Bone Marrow Transplantation↗
PubMed1981

Effect of phospholipid vesicles on endogenous RNA polymerase activity of isolated rat liver nuclei.

Negatively charged phosphatidylserine vesicles increase RNA polymerase activity of isolated rat liver nuclei, whereas inhibition is obtained with sphingomyelin, phosphatidylethanolamine, phosphatidylcholine, and phosphatidylinositol vesicles. The effect of phosphatidylserine on template activity is dose-dependent and similar to that reported for acidic polymers like heparin. These data indicate that the nature of the polar head is mainly responsible for the different effects and suggest that the phospholipids may be involved in mediating gene expression.

Animals↗
PubMed1980

[Karyologic analysis in erythroleukemia].

We report the cytogenetic data of two patients with erythroleukemia showing the chromosome Ph'. In one case the chromosome Ph', as revealed with the GTG band technique was the result of a translocation involving the chromosomes 19 and 22. The aim of this work is to provide more contribution to the knowledge of the origin of the Ph' and to give data in the field of this disease for which few cytogenetic data are available after the introduction of the banding techniques.

Aged↗