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Biomedical subjects

F Giannessi

Publications and source records attributed to F Giannessi.

At least 19 recordsLinked to original sources
PubMed2005

Inflammatory mediators and eosinophilia in atopic and non-atopic patients with nasal polyposis.

Nasal polyps are characterized by eosinophilic infiltration and presence of inflammatory mediators, such as total IgE, eosinophil cationic protein (ECP) and cytokines. The role of atopy in nasal polyp pathogenesis is still unclear. Therefore, we evaluated serum IgE levels, nasal mucus concentrations of ECP and cytokines and the number of infiltrating eosinophils in nasal tissue of polyps from atopic and non-atopic patients. Samples were obtained from a randomized population of 31 patients with nasal polyposis having endonasal sinus surgery and of 13 control subjects undergone corrective surgery of the nasal septum. On the basis of medical history of allergy, positive skin-prick tests and total IgE levels, patients with polyposis were divided in atopic (n = 13) and non-atopic (n = 18) patients. We determined levels of IgE in blood, ECP and cytokines (IL-4, IL-6, IL-8, IFN-gamma and IL-2) in nasal mucus, and number of infiltrating eosinophils in nasal tissue. The concentrations of total IgE, ECP, IL-4 and IL-8 and eosinophilia were significantly higher in all patients with nasal polyps compared with controls. Inside, all patients with nasal polyposis showed lower levels of IL-6, IFN-gamma and IL-2 compared with controls. The atopic patients showed significant differences when compared with non-atopic patients for the higher concentrations of total IgE (698.80+/-322.24 vs. 279.63+/-234.11; P < 0.0001) and IL-8 (1437.2 pg/ml+/-1250.7 vs. 605.5 pg/ml+/-481.1; P < 0.015). These findings suggest that inflammation still remains the major factor in the etiology of nasal polyposis and show different levels of inflammatory mediators into atopic and non-atopic patients.

Adult↗
PubMed2005

Ankyloglossia: a morphofunctional investigation in children.

OBJECTIVES: To provide diagnostic criteria for ankyloglossia in children by anatomical measurements; to investigate the correlation between severity of ankyloglossia and a series of morphofunctional findings; to evaluate the potential mismatch between a clinical suspect of ankyloglossia and the authentic anatomical diagnosis. DESIGN: Two different techniques of anatomical measurements and a clinical evaluation of a series of morphofunctional findings were performed. SUBJECTS AND METHODS: In 200 children referred for evaluation and treatment of tongue-tie, the length of the frenulum and the interincisal distance were measured in maximum opening of the mouth and with the tip of the tongue touching the palatal papilla. Occlusion, type of bite, tongue resting position, swallowing mechanism, oral floor mobility, frenulum insertion modality and speech were investigated. Any correlation between these morphofunctional findings and anatomical measures was investigated. RESULTS: Children with a frenulum length more than 2 cm and an interincisal distance of more than 2.3 cm were normal. In both measurements, significant correlations among mean values and other variables were observed. Moreover, three levels -- mild, moderate and severe -- of ankyloglossia were assessed. CONCLUSIONS: Length of frenulum and interincisal distance allow an assessment of severity of ankyloglossia in children. Ankyloglossia was not associated with infantile swallowing.

Anthropometry↗
PubMed2004

Distribution of 3-nitrotyrosine in the nasal polyps of atopic patients.

OBJECTIVE: To investigate whether formation of nitrotyrosine in the nasal polyps of atopic patients occurs. STUDY DESIGN: A nonrandomized, retrospective, controlled qualitative and quantitative study. METHODS: Nasal polyp tissue samples were acquired from 12 atopic patients. Control fragments of nasal mucosa were taken from 10 patients undergoing corrective surgery of the nasal septum. For routine histologic examinations, hematoxylin-eosin staining was used. Low-magnification microscopy was designed to yield pathologic characteristics and high magnification to quantify the number of eosinophils in the subepithelial connective tissue. Presence of nitrotyrosine was assessed by immunohistochemical method. RESULTS: Hematoxylin-eosin staining revealed presence of numerous eosinophils in the epithelium and in the subepithelial connective tissue. All polyps were characterized by epithelial damage. Nitrotyrosine was present in the eosinophils, in the ciliated cell, and in cells of the damaged epithelium. Goblet cells, glands, and vessels were found to be negative. No significant differences concerning the localization of nitrotyrosine were recognized among the examined nasal polyps. CONCLUSIONS: Nitrotyrosine immunohistochemical staining in nasal-polyp tissues suggested the existence of progressive epithelium injury caused by peroxynitrite. Consequences of peroxynitrite formation in eosinophils remain to be precisely established. The lack of nitrotyrosine in glands and blood vessels indicated that peroxynitrite does not have a significant role in the vascular and glandular dysfunction of nasal polyps.

Adult↗
PubMed2004

Effect of microwave radiation on Bacillus subtilis spores.

AIMS: To compare the killing efficacy and the effects exerted by microwaves and conventional heating on structural and molecular components of Bacillus subtilis spores. METHODS AND RESULTS: A microwave waveguide applicator was developed to generate a uniform and measurable distribution of the microwave electric-field amplitude. The applicator enabled the killing efficacy exerted by microwaves on B. subtilis spores to be evaluated in comparison with conventional heating at the same temperature value. The two treatments produced a similar kinetics of spore survival, while remarkably different effects on spore structures were seen. The cortex layer of the spores subjected to conductive heating was 10 times wider than that of the untreated spores; in contrast, the cortex of irradiated spores did not change. In addition, the heated spores were found to release appreciable amounts of dipicolinic acid (DPA) upon treatment, while extracellular DPA was completely undetectable in supernatants of the irradiated spores. These observations suggest that microwave radiation may promote the formation of stable complexes between DPA and other spore components (i.e. calcium ions); thus, making any release of DPA from irradiated spores undetectable. Indeed, while a decrease in measurable DPA concentrations was not produced by microwave radiation on pure DPA solutions, a significant lowering in DPA concentration was detected when this molecule was exposed to microwaves in the presence of either calcium ions or spore suspensions. CONCLUSIONS: Microwaves are as effective as conductive heating in killing B. subtilis spores, but the microwave E-field induces changes in the structural and/or molecular components of spores that differ from those attributable only to heat. SIGNIFICANCE AND IMPACT OF THE STUDY: This study provides information on the effect of microwaves on B. subtilis spore components.

Bacillus subtilis↗
PubMed2003

Cytokine secretion in nasal mucus of normal subjects and patients with allergic rhinitis.

Allergic rhinitis is regulated by the local production and release of several cytokines. The levels of Th2 cytokines IL-4, IL-6, IL-10 and the Th1 cytokine IFN-gamma were studied in nasal mucus from 30 subjects with allergic rhinitis and 45 non-atopic healthy controls. In this study a sampling technique for collecting nasal mucus, well tolerated by the subjects and with a minimal stimulation of the mucosa, was performed. The cytokine concentrations in nasal mucus samples were detected and quantitated by a new paramagnetic particle-based immunofluorescent assay system more sensitive than the conventional ELISA techniques. The new technique showed reliable values of the measured parameters. The nasal mucus from allergic patients contained significantly higher concentrations of IL-4 (25.5 +/- 3.6 pg/ml; P < 0.001) and IL-10 (1300 +/- 190 pg/ml; P < 0.05) compared to the nasal mucus from control subjects (15.2 +/- 2.3 and 532 +/- 28 pg/ml, respectively, for IL-4 and IL-10). No significant modification in IFN-gamma levels of allergic patients was found when compared to control group (respectively, 19.9 +/- 3.3 vs. 25.7 +/- 5.1 pg/ml; P > 0.05). Moreover, the allergic patients showed lower levels of IL-6 concentrations in the nasal mucus compared to control subjects (64.8 +/- 9.1 vs. 129.0 +/- 18.1 pg/ml; P = 0.0099). These data can be interpreted by the hypothesis that in response to environmental allergens there is a preferential Th2 polarity by activated CD4+ T cells and that the cytokines IL-6 and IL-10 have, respectively, an important anti-inflammatory and counterregulatory action in the pathogenesis of allergic rhinitis.

Adolescent↗
PubMed2001

Reversible carnitine palmitoyltransferase inhibitors with broad chemical diversity as potential antidiabetic agents.

A series of carnitine related compounds of general formula XCH(2)CHZRCH(2)Y were evaluated as CPT I inhibitors in intact rat liver (L-CPT I) and heart mitochondria (M-CPT I). Derivative 27 (ZR = -HNSO(2)R, R = C(12), X = trimethylammonium, Y = carboxylate, (R) form) showed the highest activity (IC(50) = 0.7 microM) along with a good selectivity (M-CPT I/L-CPTI IC(50) ratio = 4.86). Diabetic db/db mice treated orally with 27 showed a significant reduction of serum glucose levels.

3-Hydroxybutyric Acid↗
PubMed2001

Ultrastructural localization of the NADPH-diaphorase activity in the Leydig cells of aging mice.

Recently, it has been shown that nitric oxide may inhibit the Leydig cell steroidogenesis. The present paper describes, by means of NADPH-diaphorase histochemistry, the ultrastructural localization of the enzyme nitric oxide synthase in the Leydig cells of young adult and aging mice. In the young adult mice, the enzymatic reaction was mainly located in the mitochondria and in some clustered cisternae of the smooth endoplasmic reticulum. The nuclear envelope was faintly labeled. In the aging mice, most Leydig cells showed an enhanced enzymatic reaction. Labeled mitochondria were increased in number, and labeled areas of the smooth endoplasmic reticulum were more numerous and extended. In addition, a strong enzymatic reaction was recognized in the nuclear envelope. We conjecture that the impaired steroidogenesis observed in the testis of aging mammals might, at least in part, depend on the increased nitric oxide production in the Leydig cells.

Aging↗
PubMed2000

Ultracytochemical localization of the NADPH-d activity in the human nasal respiratory mucosa in vasomotor rhinitis.

OBJECTIVES: Description of the ultrastructural localization of nitric oxide synthase in the blood vessels of the nasal respiratory mucosa in patients with vasomotor rhinitis. STUDY DESIGN: This research was conducted on seven patients--men and women, ages 20 to 45 years--suffering from vasomotor rhinitis and who had undergone surgical therapy for reduction of the inferior turbinates. METHODS: To study the ultrastructural localization of nitric oxide synthase, NADPH-diaphorase cytochemistry was employed. Samples of the nasal mucosa were obtained from inferior turbinates. RESULTS: The endothelial cells of the arterioles, capillaries, venules and cavernous sinuses revealed a distribution of the enzymatic activity similar to that found in unaffected subjects. A strong enzymatic activity was recognized in the smooth muscle cells of the cavernous sinuses. The smooth muscle cells of arterioles and venules were generally found to be negative to enzymatic reaction. CONCLUSIONS: This study suggests that the vascular disorders of the vasomotor rhinitis depend, at least in part, from nitric oxide synthase induction in the smooth muscle cells of the cavernous sinuses.

Adult↗
PubMed1998

Ultrastructure of the supporting cells in the paratympanic organ of chicken, Gallus gallus domesticus.

The paratympanic organ is a specialized sensory organ of birds located in the medial wall of the tympanic cavity. It possesses a sensory epithelium formed by type II hair cells and supporting cells. The supporting cells are tall, narrow units that extend from the basement membrane to the free epithelial surface. They show a fine structure characterized by numerous mitochondria, a conspicuous Golgi complex and a well-developed RER. Moreover, some uncommon structures, probably formed by heaped RER cisternae, are frequently present in the cytoplasm. Adjacent supporting cells are connected by numerous and extensive gap junctions; moreover, small gap junctions between hair cell and supporting cells are to be found. The possible mechanical and metabolical functions of the paratympanic organ supporting cells are discussed.

Animals↗
PubMed1998

Cytochemical localisation of the NADPH diaphorase activity in the Leydig cells of the mouse.

The distribution of the NADPH diaphorase activity was studied in mouse Leydig cells by means of light and electron microscopy. When observed by the light microscope, most Leydig cells appeared intensely stained; a few cells (about 10%) showed a slightly positive or apparently negative reaction. The inhibitory effects of N(G)-nitro-L-arginine and iodonium diphenyl on frozen sections suggest the colocalisation of NADPH diaphorase reaction with nitric oxide synthase. The ultrastructural study revealed that all the Leydig cells were positively stained for NADPH diaphorase; however, a small number of cells displayed weak enzymatic activity. The reaction product was located in the mitochondria, smooth endoplasmic reticulum and lipidic vacuoles, and the nuclear envelope was also stained. The possible meaning of the NADPH diaphorase activity in the Leydig cells of mice was discussed.

Animals↗
PubMed1998

The ultrastructural localization of NADPH-diaphorase enzymatic activity in the Leydig cells of mouse. effects of ethanol administration.

The effects of the chronic ethanol treatment on the NOS-related NADPH-diaphorase activity were described in the mouse Leydig cells by means of transmission electron microscope. The recovery of the Leydig cells was also examined during a period of four weeks. About 10% of the Leydig cells showed various degrees of morphological alterations, consisting in increased number of lipid droplets, rarefaction and vacuolization of the cytoplasmic matrix. Other groups of Leydig cells (about 10%) revealed evident signs of degeneration. The NADPH-d activity was reduced both in apparently normal and injured Leydig cells and a moderate enzymatic reaction was only detected in the smooth endoplasmic reticulum. A week after the treatment an increased number of the degenerating Leydig cells and a further reduction of the enzymatic reaction were observed. Then, the Leydig cells showed a progressive recovery and four weeks after the treatment they exhibited a normal morphology and NADPH-d enzymatic reaction. These results demonstrated for the first time the inhibition of NOS activity in the Leydig cells after chronic ethanol administration.

Administration, Oral↗
PubMed1996

The ultrastructure of the sensory hairs of the paratympanic organ receptor cells in chicken.

The hair bundle of the receptor cells in the paratympanic organ of the chicken was studied by TEM, after fixation in aldehydes/osmium tetroxide or in aldehydes/osmium tetroxide/tannic acid. The bundles are formed by a kinocilium and by 40-70 stereocilia. The stereocilia are linked to each other by an extensive network of filaments. Three types of these connectors are present: basal, shaft and apical; the latter consist of side-to-side and tip-to-side connectors. We observed that the shaft connectors are well-highlighted only when tannic acid was used, while the other connectors are to be found in the conventionally fixed specimens also. The tip-to-side connector consists of a filament which joins the tip of a stereocilium with the side of an adjacent taller stereocilium; we suggest that the distortion of this filament would give rise to the mechanosensory transduction. The other connectors probably serve to maintain the regular spatial arrangement of the hair bundle and the mechanical coupling of the stereocilia. Our study shows that the general conformation of the hair bundle and the stereociliary links of the hair cells in the paratympanic organ of chicken are similar to those previously described in the hair cells of the acoustico lateralis system.

Animals↗
PubMed1996

Fine structure of the afferent synapses in the paratympanic organ of the chicken, with special reference to the synaptic bodies.

The afferent synapses of the paratympanic organ in the chicken were studied by TEM. These synapses were formed by non-myelinated fibres which reached the basal part of the hair cells. The fibres contained a number of irregular mitochondria and a few pale vesicles. In the hair cells, near the presynaptic membrane, typical synaptic bodies formed by an electron-dense core surrounded by several small pale vesicles were present. The core was connected with the vesicles by numerous thin filaments, and at same time with the presynaptic membrane by some dense projections. Moreover, we have observed that the connections between the core and the adjacent vesicles also consisted of similar structures to the dense projections. We suggest that this device is involved in the movement of the vesicles towards the presynaptic membrane. Our hypothesis is in agreement with that formulated by some authors who believe that the electron-dense core of the synaptic bodies is able to channel the vesicles to the presynaptic membrane (conveyor-belt hypothesis). Moreover, our work showed that the synaptic bodies of the paratympanic organ in the chicken are variable in density and in shape. These morphological aspects might be linked to regression-reconstitution cycles of the SBs and to the functional level of the afferent synapses.

Afferent Pathways↗
PubMed1996

Homing experiments on pigeons subjected to bilateral destruction of the paratympanic organ

The paratympanic organ (PO) in birds is a specialised sensory organ whose function is still unknown. G. Vitali, who first described the PO from observations of the behaviour of PO-lesioned pigeons, proposed that this organ was needed to maintain normal wing muscle function and called it the 'organ of flight'. This interpretation has since been disputed. To solve this controversy and to test whether the PO is involved in flight and navigation, we performed release tests on homing pigeons subjected to bilateral destruction of this organ. No impairment of either flight or navigation was observed in the lesioned pigeons.

Journal Article↗
PubMed1993

Synthesis and amnesia-reversal activity of a series of 7- and 5-membered 3-acylamino lactams.

A series of 3-(acylamino)-epsilon-caprolactams and 3-(acylamino)-2-pyrrolidinones was synthesized. Some of these compounds reversed at different degrees electroconvulsive shock- and Scopolamine-induced amnesia, using a step-through passive avoidance in mice. Classical nootropic drugs, i.e., Aniracetam, Oxiracetam, and Piracetam, were used as reference compounds. Within the analyses of data performed, we introduced a new parameter, the confrontation index (CI), which is a function of Mann-Whitney's U statistic. The CI permits a common scale of activity of substances to be generated, independently of probabilistic hypotheses, with higher scores representing higher activities. The most active compounds were characterized by the formylamino and [3-(trifluoromethyl)benzoyl]amino groups in the 3-position of the ring. None of the substances assayed showed any effect on spontaneous behavior and neurovegetative system.

Amnesia↗
PubMed1993

Involvement of basic fibroblast growth factor in suramin-induced inhibition of V79/AP4 fibroblast cell proliferation.

The V79/AP4 Chinese hamster fibroblasts were densely stained with the anti-basic fibroblast growth factor (bFGF) antibody demonstrating an endogenous production of the peptide. The in vitro proliferation of these cells was stimulated by exogenous bFGF and the maximum growth (259% increase in 3H-thymidine incorporation into DNA) was reached with bFGF 10 ng ml-1. Inhibition of bFGF-mediated mitogenic pathway was obtained with a 15-mer antisense oligodeoxynucleotide targeted against bFGF mRNA and with suramin, a drug which blocks the biological activity of heparin-binding growth factors. bFGF antisense oligomer reduced the synthesis of DNA by 79.5 and 89.5% at 20 and 60 microM, respectively; this effect was reversed by the addition of exogenous bFGF to the culture medium. A short-term exposure to suramin 300 micrograms ml-1 produced a modest reduction in 3H-thymidine incorporation but suppressed the mitogenic effect of bFGF on V79/AP4 cells. In cells treated with suramin 300 micrograms ml-1 the drug concentration increased linearly over 3 days, reaching 13.15 micrograms mg-1 of protein; cell proliferation was inhibited in a dose-related manner as evaluated by the colony formation assay (IC50: 344.22 micrograms ml-1) and by the number of mitoses observed in culture. Furthermore, the drug induced ultrastructural alterations, consisting of perinuclear cisternae swelling, chromatin condensation, nucleolar segregation and cytoplasmic vacuolations. These findings demonstrated that the endogenous production of bFGF plays an important role in V79/AP4 fibroblasts proliferation, and the inhibition of bFGF-mediated mitogenic signalling with bFGF antisense oligomer or suramin is an effective mean of reducing cell growth.

Animals↗
PubMed1993

Fine structure of the middle ear epithelium in the chicken (Gallus gallus).

The epithelium lining the tympanic cavity of the chicken possesses distinct morphological characteristics. Its ultrastructure was studied using 2 preparative techniques. (1) After fixation in Karnovsky's solution, postfixation in osmium tetroxide and embedding in Epon, the epithelium was observed to contain 2 kinds of cell: secretory and basal. The secretory cells (which we refer to as mixed granulated cells) showed numerous secretory vesicles that varied in appearance, some containing paracrystalline formations. The basal cells, located close to the basement membrane, showed no evidence of secretory activity. (2) Other specimens were immersed in Karnovsky fixative and subsequently in a mixture of glutaraldehyde and tannic acid. They were then osmicated and embedded in polar Epon mix. With this method, the epithelium was seen to be covered by electron-dense material made up of thin intertwined tubules. In addition, the secretory cells contained vesicles with concentrically arranged lamellae; such vesicles resembled the multilamellar bodies of mammalian type II pneumocytes. The hypothesis is advanced that tubules and lamellar vesicles are related to the presence of surfactant substances.

Animals↗