Search PubMed⌕ Search

Biomedical subjects

L Felici

Publications and source records attributed to L Felici.

At least 55 records · Page 3Linked to original sources
PubMed1988

Age-related changes of the metabolic profile of rat cerebellar cortex: enzyme histochemical study.

The influence of aging on the metabolic profile of cerebellar cortex was studied in young (3-month-old), adult (12-month-old) and aged (26-month-old) male Sprague-Dawley rats using enzyme histochemical techniques. The following enzymatic activities related to energy transduction were examined: lactate-(LDH) and succinate-(SDH) dehydrogenases; NADH2-tetrazolium reductase (NADHD) and alpha-glycerophosphate-dehydrogenase (GPDH). The intensity of enzymatic staining within the neuropil of molecular and granular layers as well as within the cytoplasm of Purkinje neurons of young, adult and aged animals was assessed microphotometrically. In the molecular layer LSH, SDH and NADHD levels were reduced in old rats; GPDH was decreased both in adult and old animals. In Purkinje neurons no age-related changes of the enzymatic activities under study were observed. In the granular layer LDH and GPDH showed an age-dependent loss; SDH and NADHD were unchanged. The possibility that age-related changes of the enzymatic activities under study may be due to impaired energy production mechanisms and/or represent the consequence of reduced energetic needs resulting from the documented age-dependent loss of synapses in the molecular or in the granular layers of cerebellar cortex is discussed.

Aging↗
PubMed1988

X/Y translocation in a family with X-linked ichthyosis, chondrodysplasia punctata, and mental retardation: DNA analysis reveals deletion of the steroid sulphatase gene and translocation of its Y pseudogene.

We describe a family with two male members showing an X/Y translocation (karyotype: 46,Y,der(X)t(X;Y)(p22;q11]. At physical examination both patients showed ichthyosis, mental retardation and dysmorphic features. Chondrodysplasia punctata and short stature were present in one case. Direct DNA analysis, using a steroid sulphatase cDNA probe, was performed in one patient, his mother and sister, both carriers of the translocation. We found that the translocated region of the Y chromosome includes the steroid sulphatase pseudogene. These results suggest that in our patients the X/Y translocation may be derived from a recombinational event between homologous regions located on the short arm of the X chromosome and the long arm of the Y chromosome. Clinical and molecular studies on the present family add further information for the construction of a tentative physical map of the distal Xp.

Child↗
PubMed1987

Quantitative image analysis of the density and pattern of adrenergic innervation of blood vessels of rat spinal cord.

The density and pattern of the noradrenergic innervation of the main extramedullary blood vessels of the rat spinal cord was studied using combined glyoxylic acid histofluorescence and quantitative image analysis techniques. The anterior spinal artery has a perivascular plexus of fine noradrenergic nerves rich in varicosities; the central artery has nerve fibers of various sizes; and the posterior spinal vein has a limited plexus of noradrenergic nerve fibers. The possible significance of the noradrenergic innervation of extramedullary spinal cord blood vessels is discussed.

Animals↗
PubMed1986

Redox and energetic state of red blood cells in G6PD deficiency, heterozygous beta-thalassemia and the combination of both.

The levels of ATP, ADP, AMP, NADP, NADPH, NAD, NADH and reduced glutathione were determined in the red blood cells of individuals with glucose-6-phosphate dehydrogenase (G6PD) deficiency, beta-thalassemia (beta-thal) heterozygotes and in a boy carrying both mutations. The results obtained confirmed a reduced concentration of NADPH in G6PD deficiency and showed that with the combination of both diseases, the red blood cell contained practically undetectable levels of NADPH. Assays of some red blood cell enzyme activities known to be markedly influenced by cell age suggested that a younger mean red cell population is present in beta-thal/G6PD deficiency. Thus, the marked oxidative stress caused by beta-thal, that is apparently incompatible with G6PD deficiency, in fact exists, probably because of the residual activity of this enzyme in the younger red cells.

Adenine Nucleotides↗
PubMed1986

Simple spectrophotometric quantification of urinary excretion of glycosaminoglycan sulfates.

We describe a simple, rapid, precise, and sensitive spectrophotometric method for measuring urinary glycosaminoglycan (GAG) sulfate excretion. The GAG sulfates are precipitated with cetylpyridinium chloride, resuspended in water, and mixed with the basic dye 1,9-dimethylmethylene blue to produce a complex with the polyanionic molecule of sulfated GAGs. Absorbance is read at 535 nm. The standard curve for reaction was linear up to 12 micrograms of the different GAGs: dermatan sulfate, heparan sulfate, keratan sulfate, chondroitin 4-sulfate, and chondroitin 6-sulfate. Within- and between-run precision (CV), measured at three different GAG concentrations (normal and pathological), varied from 1.6% to 2.5% and from 1.8% to 4.5%, respectively. Analytical recovery ranged from 71% to 107%. Urinary GAG excretion, measured by this procedure, correlates (r = 0.837; p less than 0.001) with the values obtained with the borate-carbazole reaction (Anal Biochem 1962;4:330-4).

Adolescent↗
PubMed1983

[Sampling of tissue from microscopic areas of the spinal cord of the chick embryo. Description of the technic and application to the study of enzymes metabolizing acetylcholine].

In the present communication we describe a very simple procedure which allows measuring the specific activity of cholinergic enzymes (Acetylcholinesterase and cholinacetyltransferase) in microscopical areas of chick embryo spinal cord. Microhomogenates were prepared as follows: i) a number of fresh cryostat sections (20 mu thick) were stained with toluidine blue; ii) the adjacent unstained sections were microdissected under stereomicroscope and tissue fragments were collected from different areas (lateral, medial and posterior columns; anterior, lateral and posterior bundles). Tissue fragments were dissolved in 10 mM sodium-phosphate buffer pH 7.4 (20-40 sections). Protein assay was performed according to Bradford (1976). AChE and ChAc were measured by radiochemical methods of Fonnum (1969, 1970). In lumbar segments of 18-day chick embryo spinal cord AChE was found in all structure investigated, by contrast ChAc was localized almost exclusively in lateral somatomotor comumns. This result indicates that ChAc can be considered a specific marker for motoneurons. The ontogeny of the cholinergic enzymes in various areas of the chick embryo spinal cord has been investigated.

Acetylcholine↗
PubMed1983

Clinical heterogeneity in Sanfilippo disease (mucopolysaccharidosis III) type D: presentation of two new cases.

Clinical, radiological and biochemical findings of two new cases of Sanfilippo disease, type D are reported. A high percentage of heparan sulfate was found in the urinary glycosaminoglycan pattern and a severe deficiency of N-acetylglucosamine-6-sulfate sulfatase was demonstrated in skin cultured fibroblasts from the patients. One of the patients presented mild intellectual impairment which differentiates him from the other cases described to date.

Child↗
PubMed1978

Ultrastructural nuclear changes in human lymphocytes following arabinosylcytosine treatment in vitro.

Human lymphocytes were separated by centrifugation and grown for 48--72 h in TC 199 medium. Synchronous cells, obtained by the addition of colchicine, were treated with arabinosylcytosine (Ara-C), an antimitotic substance which is known to produce nuclear changes in vivo and in vitro. In this case, alterations in the nuclear envelope closely resembling the malignancy associated changes described in human leukaemic cells were observed. The results allow us to suggest that such alterations may be due to a cellular derangement involving the renewal of the nuclear envelope in th G1 phase of the mitotic cycle.

Cell Nucleus↗
PubMedDate not supplied

Lactate dehydrogenase, succinate dehydrogenase and nucleotide tetrazolium reductase histochemical activities in the mesentric arteries and arterioles of young and old rats.

Age-related changes of the metabolic characteristics of large, medium and small brances of the rat superior mesenteric artery were investigated in young (4 month) and old (25 month) male Wistar rats, using enzyme histochemical techniques. The following enzymatic activities were examined: lactate dehydrogenase (LDH) and succinate dehydrogenase (SDH); NADPH(2)-tetrazolium reductase (NADPHD) and NADH(2)-tetrazolium reductase (NADHD). The intensity of enzymatic reactions within the tunica media of the large, medium and small branches and within the tunica intima of the large and medium branches of the artery was assessed microphotometrically. In young rats the reactivity of enzymes investigated is similar in both the tunica media and the intima with the exception of SDH which reacts stronger in the media than in the intima. LDH and NADHD displayed the most intense reaction whereas SDH reaction was less intense. In old rats LDH and NADPHD reactivity decreased, SDH reactivity increased in the intima of large and medium branches; and SDH increased in the media of large branches. The possibility is discussed that an impaired endothelial function may represent one of the most consistent phenomena of aging of the superior mesenteric artery.

Journal Article↗
PubMedDate not supplied

Age-related changes of glutamate dehydrogenase in the rat hippocampus: an enzyme histochemical study.

Enzyme histochemical techniques associated with microphotometry were used to evaluate the reactivity of glutamate dehydrogenase (GDH) in the hippocampus of young (3 month) adult (12 month) and old (26 month) male Sprague-Dawley rats. In young rats the highest level of enzymatic reactivity was found in the stratum oriens of the CA-1-CA-4 fields followed in descending order by the molecular layer of fascia dentata, and by the layer of mossy fibers. In all the layers investigated GDH reactivity was higher in adult that in young rats. The older animals exhibited lower GDH reactivity than adult rats in almost all of the layers and higher enzymatic reactivity than in young rats in the stratum oriens of the CA-1-CA-4 fields. The hippocampus is known to be involved in the acquisition of two-way avoidance learning and is thought to utilize glutamate as one of its main neurotransmitters. These data suggest a possible relationship between hippocampal glutamatergic transmission and impairment of acquisition of avoidance learning occurring with age. Moreover, the possibility that a decreased glutamate catabolism occurring in old rats may contribute to the neuronal loss described in the hippocampus of aged rats is discussed.

Journal Article↗
PubMedDate not supplied

Age-related changes of the noradrenergic innervation of the uterine vasculature: a fluorescence histochemical study.

Age-related changes in the density of the noradrenergic perivascular plexus supplying the uterine artery and its intrauterine branches were studied in rats 4, 12 and 24 months old using the glyoxylic acid fluorescence technique. Moreover, uterine noradrenaline levels were determined by means of high pressure liquid chromatography with electrochemical detection. No changes in the density of noradrenergic innervation or in uterine noradrenaline levels were noticeable in 12 month in comparison with 4 month rats. In contrast, a significant decrease in the density of the noradrenergic perivascular plexus of uterine artery and of its intrauterine branches as well as decrease in noradrenaline concentrations of uterine horns and cervix were observed in 24 month rats. The above findings indicate an age-related impairment of uterine noradrenergic innervation.

Journal Article↗
PubMedDate not supplied

Age-related anatomical changes in the rat hippocampus: retardation by choline alfoscerate treatment.

The age-related anatomical changes in the rat hippocampus were evaluated in male Sprague-Dawley rats of 3 (young), 12 (mature) and 24 (aged) months by counting the number of nerve cells in the CA1 and CA3 fields and in the dentate gyrus and by measuring the density of Nissl bodies in the cytoplasm of the pyramidal and granule neurons of the above areas. Moreover, the effect of 3 months choline alfoscerate treatment on the anatomical parameters examined was evaluated. The number of pyramidal neurons of the CA1 field and of granule neurons of the dentate gyrus was not significantly changed between young and mature animals, but it was decreased in aged rats. The number of pyramidal neurons of the CA3 field showed a progressive age-dependent reduction. The density of Nissl bodies was the highest in the cytoplasm of pyramidal or granule neurons in mature rats followed in descending order by young and aged animals. Choline alfoscerate treatment counteracted the age-related loss of nerve cells in the 3 hippocampal portions examined and slow-drown the decrease of Nissl bodies in the cytoplasm of pyramidal or of granule neurons in the hippocampus. The significance of changes induced by choline alfoscerate in the hippocampus of aged rats and the possible mechanism of action of the compound are discussed.

Journal Article↗
PubMedDate not supplied

Dopamine receptor immunohistochemistry in the rat choroid plexus.

1. Earlier studies have demonstrated a high density of dopamine D1-like receptor binding in the choroid plexus by light microscope autoradiography, but the dopaminergic specificity of this binding was questioned. 2. In this study the localization of dopamine receptor subtypes was investigated in the rat choroid plexus by Western blot analysis and immunohistochemistry using antibodies raised against dopamine D1-D5 receptor protein. 3. Western blot analysis revealed reactivity with immune bands of approximately 50 and 51 KDa corresponding to dopamine D1 and D5 receptors, respectively. Dopamine D1-like (D1 and D5) receptor protein immunoreactivity insensitive to superior cervical ganglionectomy was located in smooth muscle of choroid arteries and to a larger extent within choroid plexus epithelium. 4. Western blot analysis revealed reactivity with immune bands of approximately 53 KDa and 40-42 KDa corresponding to dopamine D2 and D4 receptors, respectively, and no dopamine D3 receptor reactivity. Dopamine D2-like receptor protein immunoreactivity displayed a distribution similar to that of tyrosine-hydroxylase (TH)-immunoreactive sympathetic fibres and disappeared after superior cervical ganglionectomy. It consisted in the expression of dopamine D2 and to a lesser extent of D4 receptor protein immunoreactivity perivascularly and associated with choroid epithelium. No D3 receptor protein immunoreactivity was found in rat choroid plexus. 5. The above results indicate that rat choroid plexus expresses dopamine receptor protein, being dopamine D1-like receptors predominant in epithelium and arterial smooth muscle and D2-like receptors in sympathetic nerve fibres supplying choroid plexus epithelium and vasculature. 6. These findings suggests that dopamine receptors with a different anatomical localization may modulate production of cerebrospinal fluid.

Animals↗
PubMedDate not supplied

Neurotrophins and neurotrophin receptors in human pulmonary arteries.

The localization of neurotrophins (NTs) and NT receptors was analyzed in sections of human extra- and intrapulmonary arteries by Western blot analysis and immunohistochemistry. In extrapulmonary branches of human pulmonary artery, NT and NT receptor immunoreactivity was located in the tunica intima, within endothelium, in the tunica media, within smooth muscle and in the tunica adventitia. In different sized intrapulmonary arteries, NT and NT receptor immunoreactivity was observed primarily in the tunica adventitia. A faint NT and NT receptor immunoreactivity was observed in the tunica media of large-sized branches of intrapulmonary arteries, but not within medium- or small-sized intrapulmonary vessels or in tunica intima of different sized intrapulmonary arteries. These findings suggest that NTs may have a role in the control of vascular responses in the pulmonary system acting as local paracrine or autocrine mediators. The possible relevance of the NT system in human pulmonary vasculature identified in this study is discussed.

Adolescent↗