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F Esposito

Publications and source records attributed to F Esposito.

At least 37 records · Page 2Linked to original sources
PubMed2003

Moderate coffee consumption increases plasma glutathione but not homocysteine in healthy subjects.

BACKGROUND: The consumption of unfiltered coffee, containing bioactive diterpenes, causes an increase in plasma homocysteine concentration. A slight increase in plasma homocysteine is also caused by large quantities of filtered coffee. Coffee terpenes also raise plasma glutathione in mice. AIM: To verify the effect of Italian-style coffee consumption on the plasma concentration of glutathione and homocysteine in healthy subjects. METHODS: Twenty-two volunteers consumed five cups of coffee per day for 1 week and maintained their usual diet. Five subjects were enrolled as controls. The intervention trial was preceded and followed by seven coffee-free days. RESULTS: Plasma glutathione increased by 16% (P < 0.05) on coffee consumption, and returned to the original concentration after the washout period. The increase in plasma homocysteine concentration (13% after 1 week of coffee intake) was not significant. No differences in glutathione or homocysteine concentration were observed in the control group. No variation of plasma hydroperoxide concentration was detectable. CONCLUSIONS: A coffee intake regimen, representing the average consumption of coffee drinkers in Italy, increased the plasma concentration of glutathione, but no significant increase in the plasma homocysteine concentration was detected.

Adult↗
PubMed2003

High field functional MRI.

Functional magnetic resonance imaging (fMRI) has become the most widely used approach for studying brain functions in humans. The rapid and widespread diffusion of fMRI has been favoured by the properties this technique presents, and particularly by its sensitivity in analysing brain functional phenomena and by the lack of biological invasiveness, resulting in an unprecedented and unparalleled flexibility of use. These properties of fMRI brought the functional examination of the brain within the reach of the whole neuroscience community and have appreciably stimulated the research on the functional processes of the living brain. Among the main features of fMRI, its spatial and temporal resolution represents clear advantages compared with the other methods of functional neuroimaging. In fact, the high spatial resolution of fMRI permits to produce more precise and better localised information, and its temporal resolution provides the potential of a better understanding of neural dynamics at the level of single functional areas and of the neural constituents of functional patterns. A fundamental possibility of improving spatial and temporal resolution without excessively degrading signal-to-noise ratio consists in the use of high magnetic field intensity fMRI units. Besides, high field units make the use of more demanding fMRI paradigms, like single trial event related studies, much more compatible with the need of a solid statistical evaluation. This has notably promoted the diffusion of high field MRI units for human studies throughout the world, with very high field MRI units, up to 8 T, working in a few research centres, and a larger number of MRI units with field intensity ranging between 3 and 5 T.

Brain↗
PubMed2003

Humoral responses to defined malaria antigens in children living since birth under insecticide treated curtains in Burkina Faso.

Insecticide treated materials (ITM) are considered a useful malaria control measure for endemic countries, but whether they also delay the acquisition of immunity to malaria remains unclear. This study investigates plasma antibody levels in 160 children aged 3-6 years from five villages protected by insecticide treated curtains (ITC) over 6 years and in 184 children of the same age group from five villages in the same area never covered by ITC. The antigens to which antibodies were investigated were: the Plasmodium falciparum circumsporozoite protein (CSP) repetitive sequence (NANP)5; the C-terminal domain of the P. falciparum exported protein 1 (Cter-PfExp1); three fragments of the glutamate rich protein (GLURP), referred to as R0, R1 and R2; the merozoite surface protein 3 (MSP3). The level of antibodies was lower in children from the ITC area than in children from the non-ITC area for (NANP)5, R0, R2 and MSP3. Prevalence and intensity of P. falciparum infection were similar in the two groups of children. These findings suggest that reducing the level of malaria transmission over a long period may affect the level of antibodies in children to both sporozoite and blood stage malaria antigens.

Animals↗
PubMed2003

Ethnobotanical survey and in vitro antiplasmodial activity of plants used in traditional medicine in Burkina Faso.

In Burkina Faso, most people in particular, in rural areas, use traditional medicine and medicinal plants to treat usual diseases. In the course of new antimalarial compounds, an ethnobotanical survey has been conducted in different regions. Seven plants, often cited by traditional practitioners and not chemically investigated, have been selected for an antiplasmodial screening: Pavetta crassipes (K. Schum), Acanthospermum hispidum (DC), Terminalia macroptera (Guill. et Perr), Cassia siamea (Lam), Ficus sycomorus (L), Fadogia agrestis (Schweinf. Ex Hiern) and Crossopteryx febrifuga (AFZ. Ex G. Don) Benth. Basic, chloroform, methanol, water-methanol and aqueous crude extracts have been prepared and tested on Plasmodium falciparum chloroquine-resistant W2 strain. A significant activity has been observed with alkaloid extract of P. crassipes (IC(50)<4 microg/ml), of A. hispidum, C. febrifuga, and F. agrestis (4<IC(50)<10 microg/ml). The best result is obtained with aqueous extract of T. macroptera with an IC(50)=1 microg/ml. These results confirm the traditional use of these plants.

Animals↗
PubMed2003

Remifentanil for intraoperative analgesia during the endoscopic surgical treatment of pituitary lesions.

AIM: The authors have evaluated remifentanil for intraoperative analgesia in endonasal endoscopic surgery for pituitary lesions. METHODS EXPERIMENTAL DESIGN: a perspective, randomized and comparative study between remifentanil and fentanyl for intraoperative analgesia was performed in an operating room of the neurosurgical department at University. Sixty patients of both sexes were studied and randomly divided into 2 groups. Patients were premedicated with fentanyl 0.15 microg.kg(-1) and atropine 0.01 microg.kg(-1) (group F) or with atro-pine and remifentanil 0.25 microg.kg(-1) min-1 (group R); induction was with propofol 2.0 microg.kg(-1) and maintenance with titrated infusion of propofol and for intraoperative analgesia, fentanyl as bolus injection of 1.0-1.5 microg.kg(-1) (group F) or a titrated infusion of remifentanil (group R). The following parameters were studied: MAP, HR, bleeding, awakening times, adverse effects and VAS. RESULTS: Much more stable hemodynamic parameters during surgery in patients treated with remifentanil; labetalol was administered in 10% of patients in group F; no significant differences as regards the adverse effects and VAS. Faster awakening time was obtained in the remifentanil group as compared with the fentanyl group. CONCLUSIONS: Remifentanil analgesia (mean dose of 0.37 microg.kg(-1).min-1) in patients undergoing endonasal endoscopic surgery of the sellar region provides a more efficacious cardiocirculatory control with reduced bleeding and faster psychosensorial recovery.

Adult↗
PubMed2002

Development of "de novo" aneurysms following endovascular procedures.

Two personal cases of "de novo" aneurysms of the anterior communicating artery (ACoA) occurring 9 and 4 years, respectively, after endovascular carotid occlusion are described. A review of the 30 reported cases (including our own two) of "de novo" aneurysms after occlusion of the major cerebral vessels has shown some features, including a rather long time interval after the endovascular procedure of up to 20-25 years (average 9.6 years), a preferential ACoA (36.3%) and internal carotid artery-posterior communicating artery (ICA-PCoA) (33.3%) location of the "de novo" aneurysms, and a 10% rate of multiple aneurysms. These data are compared with those of the group of reported spontaneous "de novo" aneurysms after SAH or previous aneurysm clipping. We agree that the frequency of "de novo" aneurysms after major-vessel occlusion (two among ten procedures in our series, or 20%) is higher than commonly reported (0 to 11%). For this reason, we suggest that patients who have been submitted to endovascular major-vessel occlusion be followed up for up to 20-25 years after the procedure, using non-invasive imaging studies such as MR angiography and high-resolution CT angiography. On the other hand, periodic digital angiography has a questionable risk-benefit ratio; it may be used when a "de novo" aneurysm is detected or suspected on non-invasive studies. The progressive enlargement of the ACoA after carotid occlusion, as described in our case 1, must be considered a radiological finding of risk for "de novo" aneurysm formation.

Adult↗
PubMed2002

Endoscopic endonasal transsphenoidal approach: outcome analysis of 100 consecutive procedures.

The endoscopic endonasal transsphenoidal approach has been proposed in the past decade as a minimally invasive surgical technique for the removal of pituitary tumors. From January 1997 to November 1999, 100 consecutive patients with pituitary tumors underwent endoscopic endonasal surgery, according to Jho's technique. We employed 0 degrees, 30 degrees, 45 degrees, and 70 degrees rigid endoscopes, 18 - 30 cm in length, 4 mm in diameter with an outer sleeve for irrigation and secured to a holder. Among the 87 pituitary adenomas, tumor removal was total in 51, subtotal (> 80 %) in 20 and partial in 16 cases. Four craniopharyngiomas were totally removed and an intra-suprasellar arachnoid cyst was emptied; a biopsy was performed in the two patients with a clivus chordoma. The two cases of sphenoid sinusitis were cured by surgery, the three patients with spontaneous CSF rhinorrhea were successfully treated and the residual nasal meningocele was removed. The endoscopic endonasal transsphenoidal approach appeared to be less traumatic than the traditional microsurgical approach, was very effective, and was characterized by a reduced number of complications. However, the relatively small series together with the short follow-up do not allow us to draw definitive conclusions. The post-operative reduction in hospital stay (two days in 40 of 100), significantly reduced the cost of patient's management.

Adenoma↗
PubMed2001

Molecular analysis of arterial stenosis in rat carotids.

A new model of surgical injury for the induction and development of stenosis in common rat carotids is described. This model differs from balloon angioplasty or vein graft systems currently applied on animals to develop stenosis, since it involves the entire vessel wall layers and mimics the injury occurring during arterial grafts, endarterectomy or organ transplantation. At different times following arterial damage, the pattern of expression of genes already known to be involved in the proliferation, differentiation, and apoptosis of smooth muscle cells (c-myc, Angiotensin II receptor 1, Bcl-2 and Bax alpha), as well as of Rb and Rb2 genes, whose pattern of expression after arterial injury has not yet been reported, was analyzed by semi-quantitative reverse transcription-polymerase chain reaction technique. Histological and histochemical analysis on carotid sections shows the morphological changes which occurred 30 days after surgical injury in the vessel wall. Molecular and histological data demonstrate that this model of surgical injury induces neointimal proliferation in about 30% of rats. In about 70% of the remaining rats, it induces the processes responsible for negative remodelling, namely the significant accumulation of extracellular matrix and fibers and disorganization of arterial tunics. This model is therefore available for further studies on the expression of genes involved in the arterial stenotic process, as well as for testing drugs aimed at limiting this recurrent pathophysiological phenomenon.

Animals↗
PubMed2001

Regulation of p21waf1/cip1 expression by intracellular redox conditions.

Reactive oxygen species (ROS) have been considered for a long time only as molecules for inducing oxidative damage to proteins, lipids, and nucleic acids. However, in the last few years some physiological effects of ROS have been hypothesized, consisting of the redox regulation of several biological processes, including the transduction of mitogenic signals. This means that intracellular generation of ROS could be necessary to maintain homeostasis, as well as that their formation/scavenging should be controlled processes. We developed an experimental procedure that causes redox perturbations in intact cells, based on the exposure of living cells to diethylmaleate (DEM), a GSH-depleting agent. By this procedure we demonstrated that ROS generated following DEM treatment induces a G1 arrest, that is accompanied by several redox-dependent changes in cell cycle-related proteins. One of these is the p53-independent accumulation of p21waf1/cip1, which requires the integrity of the ras-MAPK pathway. Accordingly, DEM treatment strongly activates ERK2. On the other hand, redox perturbations provoked by DEM induce several early phenomena, including p21waf1/cip1 and Rb dephosphorylation.

Animals↗
PubMed2001

Hydatid liver cyst: an 11-year experience of treatment with percutaneous aspiration and ethanol injection.

OBJECTIVE: To report an 11-year experience of treatment of hydatid liver cysts with double percutaneous aspiration and injection of alcohol. METHODS: Of the 129 patients with 174 hydatid liver cysts admitted to our department between January 1988 and January 1999, 79 patients with 119 vital hydatid liver cysts were selected for double percutaneous aspiration and injection of alcohol. Under ultrasonographic guidance, cystic cavities were first drained through fine needles, and then 95% sterile ethanol was injected and left in situ. The same procedure was repeated 3 days later without reaspiration of the injected alcohol. General anesthesia without endotracheal intubation was performed in 21 selected cases. RESULTS: Double percutaneous aspiration and injection of alcohol was completed in 78 patients with 118 hydatid liver cysts. In 1 case the procedure could not be accomplished because of an intracystic hemorrhage. A total of 254 punctures were performed, and the ethanol injected per session ranged between 12 and 250 mL. The mean hospital stay was 2.9 days (range, 2-7 days). The overall median follow-up was 48 months (range, 6-122 months). At the last ultrasonographic examination, 45.8% of the treated hydatid liver cysts had a solid pattern, 47.4% were no longer appreciable, and 6.8% had a minimal liquid component. Intracystic relapse occurred in 5% of the patients. In no case were any new cysts observed either in different hepatic segments or in any extrahepatic location. The morbidity rate was 9%, and 1 death occurred (mortality rate, 1.3%). CONCLUSIONS: Over a long period, double percutaneous aspiration and injection of alcohol proved to be a substantially safe, effective, and low-cost procedure for hydatid liver cyst treatment.

Adolescent↗
PubMed2001

Insecticide treated curtains and allelic polymorphism of Plasmodium falciparum genes in a rural area of Burkina Faso (west Africa).

To assess the possible impact of insecticide treated curtains (ITC) on the composition of a Plasmodium falciparum population in a rural area of Burkina Faso, blood samples were collected during the rainy season of 1997 from 226 children aged 3-6 years, from 4 villages equipped with ITC and 2 control villages without ITC. The analysis of fragment lengths of 3 highly polymorphic P. falciparum genes (msp-1, msp-2 and glurp) revealed a maximum number of 3 alleles per infected person for each gene. The mean number of clones per infected person was similar in villages with and without ITC.

Alleles↗
PubMed2000

In vivo effects of partial phosphorothioated AT1 receptor antisense oligonucleotides in spontaneously hypertensive and normotensive rats.

Partial phosphorothioate (PS) antisense oligodeoxynucleotides (ODNs) targeted against rat AT1 receptor mRNA have been used to control blood pressure in normotensive (WKY) and spontaneously hypertensive (SHR) rats. Molecules were injected intracerebroventricularly (i.c.v., right lateral ventricle) in freely moving animals. The antisense ODN lowered the mean arterial pressure (MAP) 24 hours (-43 mmHg+/-10) and 48 hours (-30 mmHg+/-13) after injection, while the control ODN molecule had no significant effects. The observed decrease of blood pressure was due to a specific inhibition of AT1 receptor gene expression, since the level of its mRNA, monitored by reverse transcription (RT)- polymerase chain reaction (PCR), was significantly reduced by antisense molecule (-40%), compared to sense one. In normotensive rats no effect on MAP have been observed, while AT1 receptor gene expression is reduced (-40%) by antisense treatment. It is known that SHRs have an enhanced basal activity of the central renin-angiotensin system that induces an increase in central sympathetic outflow. Instead in WKY rats the central sympathetic outflow is not conditioned by the enhanced activity of brain renin-angiotensin system. Therefore in normotensive rats although partial PS ODN reduces the AT1 mRNA level this will not result in a modification of the sympathetic outflow and no change in MAP level would be observed.

Angiotensin Receptor Antagonists↗
PubMed2000

Retinoblastoma protein dephosphorylation is an early event of cellular response to prooxidant conditions.

The modification of intracellular redox conditions with diethylmaleate (DEM), a glutathione-depleting agent, induces a p53-independent growth arrest mediated by the accumulation of p21(waf1) mRNA and protein. The same treatment also induces the retinoblastoma protein (pRb) dephosphorylation. This dephosphorylation (i) is very fast, being observed already 5 min after the exposure of the cells to DEM, (ii) is dependent on the prooxidant effects of DEM, being prevented by the treatment with N-acetylcysteine and (iii) is completely reversible, since the rephosphorylation of pRb is promptly obtained upon the removal of the glutathione-depleting agent from the culture medium. The dephosphorylation of pRb is independent of the accumulation of p21(waf1) induced by DEM; in fact, p21(waf1) levels start to increase much later after DEM treatment and accordingly cyclin-dependent kinase activities are not yet induced when pRb is already dephosphorylated following DEM treatment. Finally, pRb dephosphorylation is catalyzed by phosphatases activated by DEM treatment.

Acetylcysteine↗
PubMed2000

Generation and characterization of malaria-specific human CD8(+) lymphocyte clones: effect of natural polymorphism on T cell recognition and endogenous cognate antigen presentationby liver cells.

CD8(+) cytolytic T lymphocytes (CTL) play a fundamental role in the clearance of malaria parasites from the liver in mouse models. In humans, however, only low levels of parasite-specific CD8(+) T lymphocytes have been observed in individuals living in endemic areas. In the present study, we identified high levels of circulating CD8(+) T lymphocytes specific for a previously described HLA-A2-restricted CTL epitope of the circumsporozoite (CS) protein of Plasmodium falciparum in an adult living in Burkina Faso, as evidenced by IFN-gamma ELISPOT assay and MHC-tetramer technology. After cloning by limiting dilution culture, T cell recognition of natural CS variants of P. falciparum was studied. The results demonstrate that naturally occurring variations drastically affect residues critical for T cell recognition as only two out of nine sequences analyzed were efficiently recognized by the CTL clones. These clones were also used to analyze T cell recognition of the endogenously presented cognate antigen. We observed efficient antigen recognition of both HLA-A*0201-transfected murine antigen presenting cells and liver cells from HLA-A*0201/K(b)-transgenic mice upon infection with recombinant vaccinia virus encoding the CS protein (WR-CS). More importantly, we demonstrate for the first time efficient recognition of WR-CS-infected human liver cells.

Adult↗
PubMed2000

Antioxidative activity and carotenoid and tomatine contents in different typologies of fresh consumption tomatoes.

The phytonutrient intake associated with tomato consumption depends also on cultivar and fruit ripening stage. This work associates the antioxidative ability, the level of carotenoids, and the amount of glycoalkaloids to the main carpometric characteristics of four different typologies of tomatoes: "cherry", "cluster", "elongated," and "salad". These typologies have different weights and shapes, and they are usually consumed in the Mediterranean area at different ripening stages. Results showed that the considered tomato typologies also differ in their antioxidative ability and their carotenoid and glycoalkaloid contents. Growing conditions are also important in determining fruit characteristics: the analysis of the same cultivar of cherry tomato produced under the influence of moderate salt stress showed increases in the lipophilic antioxidative ability and the amount of carotenoid, whereas the level of glycoalkaloid decreased.

Antioxidants↗
PubMed2000

HLA-A*0201 restricted CD8+ T-lymphocyte responses to malaria: identification of new Plasmodium falciparum epitopes by IFN-gamma ELISPOT.

The role of antigen specific CD8+ T-lymphocytes in mediating protection against sporozoite-induced malaria has been well established in murine models. In humans, indirect evidence has accumulated suggesting a similar protective role for antigen-specific CD8+ T-lymphocytes. Nevertheless, the low frequency of circulating specific cells together with the lack of sensitive methods to quantify them has hampered the direct assessment of their function. Using a combination of short-term cell culture and IFN-gamma ELISPOT, we studied CD8+ T-lymphocyte responses to a panel of HLA-A*0201 binding peptides. In addition to confirming the response to already described epitopes, we also identified five new CD8+ T-lymphocyte epitopes. These epitopes are presented in pre-erythrocytic stages gene products of Plasmodium falciparum 7G8 strain and correspond to the following protein segments: circumsporozoite (CS) 64-72, 104-113, 299-308 and 403-411; liver stage antigen (LSA-1) repeat region; sporozoite surface protein 2 or thrombospondin related anonymous protein (SSP2/TRAP) 78-88 and 504-513. Four of these peptides are conserved amongst all published sequences of P. falciparum strains. We conclude that the modified IFN-gamma ELISPOT assay is a sensitive technique to monitor antigen-specific CD8+ T-lymphocyte responses in human malaria which may help in the improvement and assessment of the efficacy of malaria subunit vaccines.

Adult↗
PubMed2000

Percutaneous ethanol injection of large autonomous hyperfunctioning thyroid nodules.

PURPOSE: To verify the effectiveness of percutaneous ethanol injection (PEI) in the treatment of large (>30-mL) hyperfunctioning thyroid nodules. MATERIALS AND METHODS: Twelve patients (eight women, four men; age range, 26-76 years) with a large hyperfunctioning thyroid nodule (volume range, 33-90 mL; mean, 46.08 mL) underwent PEI treatment under ultrasonographic (US) guidance. US was used to calculate the volume of the nodules and to assess the diffusion of the ethanol in the lesions during the procedure. When incomplete necrosis of the nodule was depicted at scintigraphy performed 3 months after treatment, additional PEI sessions were performed. RESULTS: Four to 11 PEI sessions (mean, seven) were performed in each patient, with an injection of 3-14 mL of 99.8% ethanol per session (total amount of ethanol per patient, 30-108 mL; mean, 48.5 mL). At scintigraphy after treatment in all patients, recovery of extranodular uptake, absence of uptake in the nodule, and normalization of thyroid-stimulating hormone (thyrotropin) levels were observed. In all patients, US showed volume reductions of 30%-50% after 3 months and 40%-80% after 6-9 months. Side effects were self-limiting in all patients. During the 6-48-month follow-up, no recurrence was observed. CONCLUSION: PEI is an effective and safe technique for the treatment of large hyperfunctioning thyroid nodules.

Adult↗