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R Morelli

Publications and source records attributed to R Morelli.

At least 19 recordsLinked to original sources
PubMed2006

Comparison of cardioprotective abilities between the flesh and skin of grapes.

Recent studies have documented that grapes and grape juices are equally cardioprotective as red wine. The existing reports implicate that the skin and seeds of the grapes containing polyphenolic antioxidants are instrumental for the cardioprotective properties of grapes. The present study examines if the flesh of grapes also possesses any cardioprotective abilities. Three groups of randomly selected rats were fed, water only (control), flesh of the grapes (2.5 mg/kg b. wt.) or the skins (2.5 mg/kg b. wt.) for 30 days. At the end of the 30 days, isolated perfused hearts were made ischemic for 30 min followed by 2 h of reperfusion in the working mode. The results demonstrated that both flesh and skin of the grapes could protect the hearts from ischemic reperfusion injury as evidenced by improved postischemic ventricular recovery and reduced myocardial infarct size. High performance liquid chromatography (HPLC) revealed that skin and flesh contained comparative amounts of glucose, fructose, tartaric acid, malic acid, shikimic acid, and trans-caftaric acid. In addition, the flesh contained reduced amounts (compared to skin) of cis-coutaric, trans-coutaric, caffeic, p-coumaric, cinnamics, and catechin/epicatechin. Total polyphenolic index was also lower in flesh compared to skin. The anthocyanins were present exclusively in the skin. Electron paramagnetic resonance (EPR) spectrometry of hydroxy radicals indicated that both flesh and skins possessed equal amount of ROS scavenging activities. Total malonaldehyde content in the heart was reduced comparatively with either flesh or skin. The results indicate for the first time that the flesh of grapes are equally cardioprotective as skin, and antioxidant potential of skin and flesh of grapes are comparable with each other despite of the fact that flesh does not possess any anthocyanin activities.

Animals↗
PubMed2006

The introduction of the stilbene synthase gene enhances the natural antiradical activity of Lycopersicon esculentum mill.

Tomato (Lycopersicon esculentum) is a vegetable rich in antioxidants, such as lycopene, lutein, and zeaxanthin. Their presence is responsible for the characteristic ability of this product to inhibit the formation of reactive oxygen species, including singlet oxygen. The grapes and wines derived from grapes also contain powerful antioxidants. The antioxidant effect is derived from the polyphenols such as resveratrol and proanthocyanidin. Resveratrol is phytoalexin that is synthesized via the activation of the gene, stilbene synthase (STS). We decided to determine if the introduction of this gene into Lycopersicon esculentum Mill could modify its antioxidant activity. Using Electronic Paramagnetic Resonance (EPR) spectroscopy, which permits the detection of antiradical activity, especially *OH (hydroxyl radical), we showed that the antioxidant activity of the products, into which the gene STS had been introduced, was almost double than that of natural products and that their activity was especially pronounced due to ripening. Moreover, resveratrol concentrations in modified tomatoes were much higher than that found in the individual fruit. In the isolated hearts subjected to ischemia/reperfusion, the rats fed with modified tomato exhibited better cardiac performance, reduced myocardial infarct size and decreased number of apoptotic cardiomyocytes, and reduced oxidative stress compared to unmodified tomato or resveratrol alone indicating superior cardioprotective abilities of modified tomatoes.

Acyltransferases↗
PubMed2004

EPR evaluation of the antiradical activity of wines containing high concentrations of resveratrol.

The ability of two samples of red wine with different resveratrol concentrations to inhibit hydroxyl radicals (*OH) produced by a Fenton-type reaction was assessed using the method of electronic paramagnetic resonance (EPR). One sample was an autochthonous wine, Uvalino, which has a very high resveratrol concentration; the second was another red wine with a much lower resveratrol concentration. The ability of the sample of Uvalino wine to obstruct hydroxyl radicals was evident, but it wasn't much better than the ability of the sample of wine with a lower resveratrol concentration. The resveratrol concentration of wine is an important factor for the inhibition of the formation of free radicals, especially hydroxyl radicals; however, it is not the only one responsible for this property of wine. Resveratrol concentration can act synergically with other factors, such as polyphenols, which are also contained in wine and have antioxidant properties.

Drug Evaluation, Preclinical↗
PubMed2004

Effects of uvalino, a new autochthonous wine, on the inhibition of the production of hydroxyl radicals.

In view of the high concentration of resveratrol found in a new autochthonous wine (Uvalino) and the notable antioxidant activity of this substance, we decided to assess whether this wine could inhibit the production of free radicals. Nowadays, free radicals are considered to be the most noxious factors for tissues, triggering the development of many diseases. The assessments were carried out using a direct and more precise technique, electronic paramagnetic resonance (EPR), which is able to detect the ability of an antioxidant agent to inhibit the formation of hydroxyl radicals (*OH), which are among the most noxious reactive oxygen species (ROS). The results show that Uvalino wine is able to eliminate ROS production almost completely. Consequently, it has beneficial effects on health in all the diseases in which ROS plays an important pathogenetic role.

Antioxidants↗
PubMed2003

Evaluation of the antioxidant activity of new carotenoid-like compounds by electron paramagnetic resonance.

The antioxidant activity of a novel series of derivatives with a carotenoid-like structure was studied. These derivatives have recently been isolated chemically as a result of studies on the pigments present in a particular species of birds, namely parrots. These novel derivatives, which are also called parrodienes, have been proved to possess interesting biological properties that differ from those that carotenoids are known to have. The objective of this study was to demonstrate the ability of these novel compounds to inhibit the formation of reactive oxygen species, especially their ability to block the formation of hydroxyl radicals, which are among the most reactive products of oxygen reactions and which produce the greatest damage to cells and tissues. The technique used to assess this antioxidant capacity of parrodienes was electron paramagnetic resonance, which allows direct assessment of inhibition of hydroxyl radical formation (.OH). The results show that these derivatives, especially octatriene, are able to exert evident antioxidant activity, thus confirming that their antioxidant properties are important for their biological activity.

Aldehydes↗
PubMed2000

Sentinel lymph node biopsy in patients with primary cutaneous melanoma: study of 455 cases.

BACKGROUND: The role of elective lymph node dissection in the treatment of patients with primary melanoma is a debated topic in surgical oncology. However, recent data assure a survival improvement with this technique only for patients harbouring nodal metastases. The emergence of a new procedure of lymphatic mapping permits the identification of the sentinel lymph node (SLN), the first draining node from the site of cutaneous melanoma, which has demonstrated to be predictive of staging of the entire regional lymphatic basin and useful in selecting for lymph node dissection only those patients who have early micrometastases. OBJECTIVES: To verify in a large series of cases whether a combination of preoperative lymphoscintigraphy and intraoperative mapping with both vital blue dye and a hand-held gamma probe would permit an increase of the rate of successful SLN localization up to 100%; to check the utility of a wider application of SLN biopsy in patients with thin melanomas owing to a favourable risk-benefit ratio; to determine the predictive value of SLN biopsy by performing regional lymphadenectomy in patients who have pathological evidence of metastases in the SLN; to observe whether the use of SLN technique and selective lymphadenectomy might improve the clinical evolution of patients and favour low rates of recurrence. METHODS: In 425 AJCC stage I or II melanoma patients, preoperative lymphoscintigraphy by intracutaneous injection of Tc99m-labelled albumin nanocolloids around the tumour or the tumour's excision scar was combined with the intraoperative use of a hand-held gamma probe and patent blue V mapping technique, in order to identify and harvest the SLN. In five cases the blue dye was voluntarily not used because of previous allergic reactions. In other 25 preliminary cases the procedure was performed using the blue dye alone (10 cases) or combined with a preoperative lymphoscintigraphy (15 cases). A wide excision of the primary site was then undertaken in all cases. SLNs were sent to the pathologist for serial sectioning and permanent preparations with histological and immunohistochemical examination. Patients with pathological evidence of metastatic disease in SLN returned for regional lymphadenectomy. RESULTS: The combined use of lymphoscintigraphy, blue dye and gamma probe allowed us to identify one or more SLNs in all cases except for two (99.5% rate of success). In 70 melanomas less than 0.76 mm thick, SLNs were negative for metastases, whereas in 380 patients with thicker tumours micrometastases were demonstrated in 75 cases (19.7%). In patients with SLN metastases who underwent regional lymph node dissection, no other metastases were found three times out of four. After a median follow-up period of 18 months the rate of recurrence of the disease in 335 patients with SLN free of metastasis was low (5.4%) with a very low regional nodal recurrence (1.2%). Moreover, the worsening of the disease did not exceed 18.5% of cases with metastasis in SLN. CONCLUSIONS: Our data confirm in a large series of cases that the SLN biopsy is extremely selective and useful to find early micrometastases and to identify patients needing regional lymphadenectomy and adjuvant immunotherapy. Patients with intermediate thickness melanoma (0.76-4.0 mm) should be informed on the availability of such a revolutionary procedure, which represents a new opportunity in primary melanoma surgery.

Adolescent↗
PubMed1999

Sentinel node biopsy and selective lymph node dissection in cutaneous melanoma patients.

Sentinel node biopsy allows an accurate selection of melanoma patients to be submitted to therapeutic dissection. From February 1994 to August 1998, at the National Cancer Institute, S. Pio X Hospital in Milan and Bufalini Hospital in Cesena, 580 sentinel node biopsies were performed in 540 stage I melanoma patients (242 males; 298 females; median age 47). Primary melanoma was located in the trunk in 201 patients, in lower limbs in 242 cases, in upper limbs in 80 cases and in head and neck in 17 patients. Injection of blue dye for sentinel node identification was performed in all cases; 372 patients were submitted to preoperative lymphoscintigraphy and in 272 cases an intraoperatory probe for a radioguided biopsy was utilized. Sentinel node identification rate was 91%. Sentinel node positivity rate was 15%. Frozen sections were examined in 199 cases. Distribution of positive cases according to primary thickness is the following: <1 mm: 1%; 1-1.99 mm: 5%; 2-2.99 mm: 18% and > or =3 mm: 27%. Sentinel node appeared to be the only metastatic node in 77% of patients submitted to dissection. The adoption of preoperative lymphoscintigraphy and the intraoperative use of the gamma probe contributed substantially in S.N. identification. No complications caused by the procedure were reported. Eight patients had a regional node relapse after a negative sentinel node biopsy and were submitted to therapeutic distant dissection. Currently 513 patients are alive with no evidence of disease. Present data confirm the feasibility and safety of sentinel node technique for selection of patients to be submitted to radical node dissection and to eventual adjuvant treatments.

Adolescent↗
PubMed1999

[Anatomo-pathologic study of sentinel lymph nodes in melanoma. Analysis of 200 cases].

Pathologic evaluation of sentinel lymph node represents a new technique for managing high-risk primary melanoma. We examined the sentinel lymph node biopsies of 200 patients affected by primary melanomas of trunk, limbs, head and neck, who had been operated at "M. Bufalini" Hospital between April 1996 and July 1998. The lymphatic mapping has been performed through the preoperative intradermal injection of vital blue dye and technetium-labelled albumin. 319 sentinel lymph nodes were harvested and the 11.3% (15% of patients) were positive for melanoma metastases. No metastases were found in melanomas < or = 1 mm. The percentage of positive sentinel lymph nodes in patients with melanomas > 1 mm in thickness was 16.3% (22% of patients). In 5 cases (2.5%) nodal nevi were found, 1 of which was associated with micrometastasis. All 30 patients with positive sentinel lymph nodes underwent regional lymph node dissection and 555 lymph nodes were harvested. Melanoma metastases were found in only 7 patients, in 31 lymph nodes. The procedure of SLN detection and biopsy is a feasible surgical approach to melanoma patients. It is extremely useful in finding early metastases and in effective pathologic staging. As a consequence of the very low incidence of metastases in the sentinel lymph nodes of patients with thin melanomas, we suggest the sentinel lymph node mapping should be offered to patients with primary melanomas at least 1 mm in depth.

Adolescent↗
PubMed1997

Capsular pseudoinvasion after fine-needle aspiration of follicular adenomas of the thyroid.

Two cases of an unusual finding of capsular pseudoinvasion in follicular thyroid adenomas after fine-needle aspiration (FNA) procedures are reported. These capsular breaches were noted along the hemorrhagic needle track, which traversed the normal peripheral thyroid parenchyma into the lesions. A reparative reaction was seen at some points along one of the tracks. Histologic examination also showed extrusion of the tumor parenchyma through the capsular interruption in one case. Surgical pathologists should be aware of this rare complication of FNA of thyroid follicular adenomas as a differential diagnosis of minimally invasive (encapsulated) follicular carcinoma.

Adenoma↗
PubMed1996

Superinfection by Listeria monocytogenes of cultured human enterocyte-like cells infected with poliovirus or rotavirus.

A mixed infection with either rotavirus or poliovirus and Listeria monocytogenes was analysed in Caco-2 cells, a tumour-derived cell line, highly susceptible to these pathogens. The multiplication of these pathogens, whose usual site of entry and/or replication is the intestine, was also followed by electron microscopy. Results obtained showed an increase of L. monocytogenes internalisation in cells infected with rotavirus, whereas the preinfection with poliovirus had only a slight interfering effect on bacterial entry. Analysis of L. monocytogenes multiplication in virus-infected cells revealed that rotavirus also promoted bacterial replication, which poliovirus hampered replication. Concerning the effect of Caco-2 cell invasion by L. monocytogenes on viral replication, we observed an increase in rotavirus antigen synthesis but no significant effect on poliovirus yield under our experimental conditions.

Caco-2 Cells↗
PubMed1996

Protective effect of the nitroxide tempol against the cardiotoxicity of adriamycin.

Nitroxides are cell permeable, stable radicals that have been shown to exert antioxidant effects in several experimental models. In the present study, the ability of the piperidine nitroxide TEMPOL to prevent the acute cardiac toxicity of Adriamycin (ADR), which depends on oxygen-derived free radical generation, was assessed in isolated rat hearts. The results obtained show that TEMPOL (2.5 mM) significantly reduces the contractile impairment as well as the lipid peroxidation observed in rat heart preparations perfused with 100 micrograms/ml of ADR for 60 min. Both direct interaction with free radicals and decrease of Fe(II) availability (by stable oxidation and/or by chelation) seem to contribute to the cardioprotective effect to TEMPOL. HPLC and EPR studies of the subcellular distribution of TEMPOL indicate that substantial amounts of the nitroxide localize to the mitochondrial and microsomal fractions, in an ordered environment possibly corresponding to the interface between membrane and aqueous compartments.

Analysis of Variance↗
PubMed1996

Enteropathogens associated with childhood diarrhea in Italy. The Italian Study Group on Gastrointestinal Infections.

BACKGROUND: Infectious diarrheal diseases remain an important cause of childhood morbidity in industrialized countries. The knowledge of the etiology and epidemiology of childhood diarrhea in a given area is needed to plan any measure designed to prevent or ameliorate diarrheal illness and to develop practice guidelines for the most appropriate stool examination procedures. METHODS: We evaluated 618 children with diarrhea and 135 controls prospectively for viral, bacterial and parasitic enteric pathogens. Diarrheagenic Escherichia coli was identified by gene probes specific to different virulence factors. Stool filtrates were examined for the presence of free bacterial toxins by a cell culture cytotoxicity assay. Clinical and epidemiologic data were recorded and analyzed in relation to microbiologic findings. RESULTS: Enteropathogens were identified in 59% of children with diarrhea and in 10.4% of asymptomatic controls. The agents mainly associated with disease were rotavirus (23.6%), Salmonella (19.2%) and Campylobacter (7.9%). Rotavirus was significantly more frequent among children observed as inpatients whereas Campylobacter was significantly more common in outpatients. Infections with diarrheagenic E. coli, Shigella flexneri, yersinia enterocolitica, Cryptosporidium and Giardia were observed in a limited number of patients. The clinical presentation of children was not sufficiently characteristic to permit presumptive diagnosis of a specific pathogen. conversely the presence of blood and/or leukocytes in stools had a high positive predictive value for Salmonella or Campylobacter infection. CONCLUSION: The results of this study will be useful for planning strategies to prevent and control diarrheal diseases in our country.

Child↗
PubMed1996

The effects of inhibitors of vacuolar acidification on the release of Listeria monocytogenes from phagosomes of Caco-2 cells.

To evaluate the role of the acidic pH of phagosomes on the invasive ability and fate of Listeria monocytogenes within host cells, entry and replication of this gram-positive bacterium in a human enterocyte-like cell line (Caco-2) were investigated by a combination of biochemical and ultrastructural approaches. The effects of inhibitors of vacuolar acidification--the lipophilic weak base ammonium chloride, the carboxylic ionophore monensin and the vacuolar proton ATPase inhibitor bafilomycin A1--on the bacterial invasion pathway were analysed. These agents, which raise the intracellular vesicle acidic pH of living cells by different mechanisms, affected L. monocytogenes replication in Caco-2 cells. Bacteria internalised by bafilomycin-treated cells were unable to escape from phagosomes, as demonstrated by electronmicroscopy. The results provide evidence that low pH is required for efficient intracellular growth of L. monocytogenes.

Ammonium Chloride↗
PubMed1996

Characteristics of Escherichia coli strains belonging to enteropathogenic E. coli serogroups isolated in Italy from children with diarrhea.

Fifty-five Escherichia coli strains belonging to enteropathogenic E. coli (EPEC) serogroups were examined for phenotypic and genetic factors associated with virulence. The strains were isolated in Italy from children with diarrhea and identified as EPEC by clinical laboratories using commercially available antisera. O:H serotyping showed that 35 strains (27 of O26, O111, and O128 serogroups) belonged to 11 serotypes considered to be classical EPEC O:H serotypes. The other 20 isolates were classified as 15 nonclassical EPEC O:H serotypes. All the potential EPEC virulence factors associated with bacterial adhesion (localized adherence, fluorescentactin staining test positivity, presence of the attaching and effacing [eaeA] gene), the production of verotoxin, and the positivity with the enterohemorrhagic E. coli probe were significantly more frequent among isolates belonging to classical than nonclassical serotypes. Strains displaying an aggregative adhesion and hybridizing with the enteroaggregative DNA probe were found in serogroups O86, O111, and O126. Verotoxin-producing isolates belonged to serogroups O26, O111, and O128. Only one of the isolates hybridized with the EPEC adherence factor (EAF) probe, but 33 strains gave positive results with the eae probe, confirming that the former is more suitable in epidemiological studies in European countries. These results indicate that up to 75% of strains identified as EPEC by commercial antisera may possess potential virulence properties and/or belong to classical EPEC O:H serotypes and suggest that O grouping is still a useful diagnostic tool for presumptive identification of diarrheagenic E. coli in clinical laboratories.

Adhesins, Bacterial↗
PubMed1996

Proximal subungual onychomycosis due to Microsporum canis.

A case of proximal subungual onychomycosis due to Microsporum canis in a 36-year-old woman is presented. The onychomycosis involved the left thumb and the little fingernails, with thinning of the nail plate and crumbling of the nail plate surface. A milky-white discoloration of the proximal portion of the left thumbnail was also evident. A 2-mm longitudinal nail biopsy showed a large number of fungal elements in the whole length of the nail plate. Fungal hyphae were more numerous in the ventral nail plate and produced detachment of the superficial nail plate. The nail bed was not invaded by fungal elements and was devoid of inflammatory changes. Proximal subungual onychomycosis is uncommon in immunocompetent individuals but has frequently been described in patients with AIDS. In our patient, in whom the proximal subungual onychomycosis was due to M. canis, there were no clinical or biochemical signs of immunodeficiency. Oral treatment with terbinafine, 250 mg/daily for 2 months, produced clinical and mycological cure.

Adult↗
PubMed1995

Differential inhibition of superoxide, hydroxyl and peroxyl radicals by nimesulide and its main metabolite 4-hydroxynimesulide.

The superoxide and hydroxyl radical scavenging activities of nimesulide (CAS 51803-78-2) and its main metabolite 4-hydroxynimesulide (CAS 109032-22-6) were investigated by Electron Spin Resonance (ESR) spectroscopy, with the spin trapping technique. Hydroxynimesulide is a good scavenger of both O2 degrees- (IC50 = 40 mumol/l) and HO degree (IC50 = 54.8 mumol/l) radicals, and its high reactivity towards HO degree was confirmed by the rate constant for reaction with HO degree (K = 8.9 x 10(10) mol-1 l s-1) determined by competition kinetic studies with 5,5-dimethyl-l-pyrroline-N-oxide. Nimesulide, which has been shown by ESR to be inactive as a superoxide quencher, has a rate constant of reaction with HO degree slightly greater than that of its metabolite (3.3 x 10(11) mol-1 l s-1). In the HO degree-induced peroxidation of phosphatidylcholine (PC) liposomes, both compounds act as potent preventive antioxidants, but the HO degree entrapping capacity of the parent drug was again greater than that of hydroxynimesulide (IC50 2.12 vs 3.84 mumol/l). The metabolite is also a potent scavenger of the peroxyl radical (ROO degree) in the propagation phase of PC peroxidation (marker conjugated dienes), with an IC50 = 2.67 mumol/l; at 5 mumol/l it induces a lag time in the decomposition of PC hydroperoxides (PC-OOH) into aldehydic products of 40 h longer than in the controls (markers: conjugated dienes and total carbonyl functions). In PC liposomes, in the presence of preformed PC-OOH, the metabolite prevents PC peroxidation stimulated by 5 mumol/l Fe2+, via the Fenton reaction (marker: conjugated dienes), at the micromolar level (IC50 = 17 mumol/l) through an anti-free radical activity and a free iron chelating mechanism. Hydroxynimesulide in fact interacts with Fe2+ ions, giving rise to a strong complex, with a stability constant (log K) estimated to be around 8/9. In addition, hydroxynimesulide efficiently protects ex vivo synovial fluid lipids from the oxidative stress induced by Fe2+/ascorbate, already at 10 mumol/l (marker: thiobarbituric acid reactive substances). These results provide evidence for strong antioxidant and iron-chelating properties of 4-hydroxynimesulide, which can act synergistically with the specific HO degree scavenging activity of the parent drug in preventing and limiting in vivo the free radical-mediated tissue damage in both acute and chronic inflammatory situations.

Anti-Inflammatory Agents, Non-Steroidal↗