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S Natoli

Publications and source records attributed to S Natoli.

11 recordsLinked to original sources
PubMed2003

Measurement of oxysterols and alpha-tocopherol in plasma and tissue samples as indices of oxidant stress status.

Oxidant stress seems to play a role in several setting of human pathology, such as atherosclerosis, cancer, and aging. The study of oxidant stress in human disease should be based on the evaluation of either sensitive and specific markers of enhanced oxidant stress, such as oxysterols, or antioxidant defense, by measuring alpha-tocopherol. We have developed a rapid method to measure the oxysterols 7beta-hydroxycholesterol and 7-ketocholesterol in plasma (50 healthy subjects) and tissue as an index of oxidant stress in vivo, and from the same sample alpha-tocopherol content. The mean plasma concentration of 7beta-hydroxycholesterol and 7-ketocholesterol was 4.6+/-1.1 and 13.4+/-7.6 ng/mL, respectively. Plasma alpha-tocopherol concentration was 5.8+/-1.0 micromol/mol cholesterol. Samples from atherosclerotic plaques contained 20 times more cholesterol, about 45 times higher oxysterols levels, and 600 times more alpha-tocopherol compared to normal arteries. No significant difference in cholesterol and oxysterol content was observed between cirrhotic and normal liver. However, cirrhotic liver contained significantly smaller concentration of alpha-tocopherol compared to normal liver. In conclusion, we have developed a rapid and reliable method for the assay of cholesterol oxidation products and alpha-tocopherol in plasma and tissue useful for estimation of oxidant stress/antioxidant balance.

Adult↗
PubMed2000

Superoxide anion and hydroxyl radical release by collagen-induced platelet aggregation--role of arachidonic acid metabolism.

Previous study demonstrated that platelets undergoing anoxia-reoxygenation generate superoxide anion (O2-) and hydroxyl radical (OH ) which in turn contribute to activate arachidonic acid (AA) metabolism. However it has not been clarified if oxygen free radicals (OFRs) are also generated when platelets are aggregated by common agonists. We used two probes, i.e. lucigenin and salicylic acid (SA), to measure platelet release of O2- and OH(0), respectively. Among the agonists used, such as ADP, thrombin and collagen, the release of O2- and OH was observed mainly when platelets were stimulated with collagen. Such release was inhibited in platelets pre-treated by aspirin suggesting that AA metabolism was the main source of O2- and OH(0) formation. To further analyze this relationship, O2- and OH(0) formation was measured during AA-stimulated platelet aggregation (PA); we observed that O2- and OH(0) release were dependent upon AA concentration. Furthermore, we found that the incubation of platelets with AACOCF3, a potent inhibitor of cytosolic phospholipase A2, inhibited collagen-induced platelet O2- and OH(0) release. The incubation of platelets with salicylic acid or ascorbic acid, which blunt OH and O2- respectively, inhibited both collagen-induced platelet aggregation and AA-release. This study demonstrated that collagen-induced platelet aggregation is associated with O2- and OH formation, which is dependent upon AA release and metabolism.

Adenosine Diphosphate↗
PubMed1999

[Oxidative stress and hypercholesterolemia: increase of radical hydroxyl in patients with hypercholesterolemia].

A close relationship exists between high blood cholesterol levels and atherosclerosis. This relationship, which represents an important risk factor for cardiovascular diseases, may be dependent on enhanced oxidative stress. To investigate this hypothesis, we studied 20 patients (12 females and 8 males, aged between 40 and 65 years) with high blood cholesterol levels (240-450 mg/dl) but without other risk factors for atherosclerosis and 20 healthy individuals matched for sex and age, with blood cholesterol levels < 240 mg/dl. We elaborated a laboratory technique that identifies two metabolites of the hydroxyl radical, the 2,3 and the 2,5 dihydroxybenzoic acid (DHBA), in basal conditions and after stimulation by 0.5-1 microM formyl-methionine-leucyl-phenylalanine, which is a specific activator of leukocytes. Results show that patients with hypercholesterolemia have a significant increase of 2,3 e 2,5 DHBA both in basal conditions and after stimulation (p = 0.03). A significant correlation (rho = 0.474; p = 0.004) was found between 2,3-2,5 DHBA and serum cholesterol. This study shows that patients with hypercholesterolemia have enhanced leukocyte oxidative stress and suggests that cholesterol could play a pivotal role.

Adult↗
PubMed1999

The integrated treatment of peritoneal carcinomatosis. A preliminary experience.

Some low-grade malignant tumors arising in the abdomen, lack of infiltrative attitude and "redistribute" on the peritoneum with no extraregional spreading. In this cases the complete tumor cytoreduction followed by intra- or postoperative regional chemotherapy has curative intent. Peritonectomy is the complete removal of all the parietal peritoneum and the visceral peritoneum involved by disease. After peritonectomy hyperthermic antiblastic perfusion is carried out throughout the abdomino-pelvic cavity for 60 minutes, at a temperature of 41.5 degrees C, with mitomycin C (3.3 mg/m2/Lt of perfusate) and cisplatin (25 mg/m2/Lt) (appendicular or colorectal primary), or cisplatin alone is (ovarian primary). Alternatively the immediate postoperative regional chemotherapy is performed with 5-fluorouracil (13.5 mg/Kg) and Lederfolin (125 mg/m2) (colic or appendicular tumor) or cisplatin (25 ng/m2) (ovarian tumor), each day for 5 days. Twenty patients affected by extensive peritoneal carcinomatosis (12 ovarian, 5 colonic, 1 appendicular, 1 mesothelial and 1 gastric primary) were submitted to peritonectomy with no residual macroscopic disease in all cases except three. Six patients were treated with intraoperative intra-abdominal hyperthermic antiblastic perfusion, while immediate postoperative intra-abdominal chemotherapy was given in 4 patients and systemic chemotherapy in other 5. Hospital mortality was 20%. At a mean follow-up of 11 months 14 patients are alive, 11 without disease and the median overall survival is 10.2 months. The curative potential of the combined therapeutic approach seems high in patients with peritoneal carcinomatosis from ovarian or colorectal primary not responding to systemic chemotherapy. Selection criteria of patients can strictly affect the surgical risk and the treatment has to be reserved for controlled clinical trials.

Abdominal Neoplasms↗
PubMed1996

Toxic shock syndrome due to group C streptococci. A case report.

BACKGROUND: Streptococcal toxic shock-like syndrome is a life-threatening illness which is on the increase. In early reports, only group A beta-hemolytic streptococcus was associated with the disease, but recent evidence indicates non-A streptococci groups are also involved. OBSERVATIONS: We describe the first reported case of streptococcal toxic shock-like syndrome caused by a group C strain in Italy. Prior to the disease, the patient, a 46-year-old man, had been in good health and had only a 3-day history of sore throat, low grade fever, vomiting, diarrhea, and myalgia before admission. Initially, diagnosis was based only on clinical evidence: shock, multiorgan failure, profound hypothermia, and no apparent signs of infection. Toxic cardiomyopathy was also present. RESULTS: Positive throat swab and blood culture confirmed a "definite case" following established criteria. Anamnesis showed a diagnosis of monoclonal gammopathy. Antibiotic treatment was begun immediately on admission of the patient, who was discharged 20 days later in good health. CONCLUSIONS: This case illustrates how an early diagnosis and prompt antibiotic therapy can determine a more favorable outcome.

Humans↗
PubMed1995

[Tetraplegia and acute respiratory insufficiency from an ischemic cervical medulla lesion after cocaine use. A clinical case].

The article deals with a case report on tetraplegia and acute respiratory failure following ischemic damage of the spinal medulla in the cervical tract due to cocaine assumption. The ischemic damaged produced by cocaine usually injure the great vessels of the cranial base. The case report is particular because of the area and the seize of the injured vessel. Finally, the most important hypotheses about the pathogenesis in the ischemic cerebrovascular cocaine-induced damages are debated.

Adult↗
PubMed1995

[Thrombocytopenia and thrombophilic state in heparin therapy].

The authors report two clinical cases of thrombocytopenia and thrombosis which occurred during profilaxys and therapy with heparin. The mechanisms involved are reviewed and the possible therapeutic role of heparin-like drugs is discussed according to data presented in the international literature.

Anticoagulants↗
PubMed1987

[Not Available].

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History, Ancient↗
PubMedDate not supplied

Complications with fully implantable venous access systems in oncologic patients.

AIMS: To evaluate the complications caused by long-term central venous catheterization in patients with malignant hemopathies or solid tumors. METHODS: Retrospective study from June 1988 to June 1993 in 211 consecutive patients who required 223 venous access devices for long-term use. A consistent analysis was possible only in 161 of these patients. RESULTS: Fourteen catheter systems were removed for complications. Infections were the most common complications, with an overall incidence rate of 9.6%, i.e. 0.033/100 catheter days/patient. A significant difference was noted between the two groups of patients: 10 cases (24%) in malignant hemopathies, 6 cases (4.8%) in solid tumors (P = 0.0002). The main mechanical complication was thrombosis, with an incidence rate of 3%. CONCLUSIONS: Given the cost-benefit ratio, our study indicates that fully implantable venous access systems in oncologic patients are extremely useful.

Adolescent↗