Paolo Francesco Alberti

Nitroaspirin plus clopidogrel versus aspirin plus clopidogrel against platelet thromboembolism and intimal thickening in mice

Clopidogrel plus aspirin is the treatment of choice for patients undergoing percutaneous, coronary interventions with stenting, but it does not prevent restenosis. NCX-4016, a nitric oxide-releasing aspirin (nitroaspirin), exerts a wider range of antiplatelet actions compared to aspirin, superior antithrombotic activity and reduces restenosis after arterial injury in animals. The aim of the present study was to compare the combination of nitroaspirin plus clopidogrel with aspirin plus clopidogrel in a model of platelet pulmonary thromboembolism, bleeding and intimal thickening in mice. Drugs were administered orally for 5 days; the antithrombotic effects were evaluated against collagen plus epinephrine-induced pulmonary thromboembolism, the haemorrhagic effects by tail transection bleeding time and the effects on neointima proliferation by histomorphology of photochemically injured femoral arteries. Lung platelet emboli were reduced significantly and more effectively by nitroaspirin plus clopidogrel (-56%, p<0.05 vs control) than by aspirin plus clopidogrel (-26%, p<0.05 vs control). Ex vivo platelet aggregation was inhibited maximally by nitroaspirin plus clopidogrel. Aspirin plus clopidogrel strikingly prolonged the bleeding time while nitroaspirin plus clopidogrel induced a lesser prolongation. Nitroaspirin plus clopidogrel significantly reduced intimal thickening of the femoral artery while aspirin plus clopidogrel was ineffective. Nitroaspirin plus clopidogrel is more effective and less prohaemorrhagic than aspirin plus clopidogrel in mice; provided these data are confirmed in other animal models, nitroaspirin plus clopidogrel may represent a new regimen to be tested in patients undergoing coronary revascularization procedures.

Nitric oxide enhances the anti-inflammatory and anti-atherogenic activity of atorvastatin in a mouse model of accelerated atherosclerosis.

AIMS The aim of the present study was to assess whether the addition of a nitric oxide (NO)-donating moiety to atorvastatin enhances anti-inflammatory and anti-atherogenic effects in an animal model of endothelial dysfunction, systemic peroxidation and inflammation, and accelerated atherosclerosis. METHODS AND RESULTS Low-density lipoprotein receptor (LDLR)(-/-) mice kept on a high-fat diet (HFD) for 16 weeks underwent photochemical injury to the femoral artery with the local production of oxygen radicals. HFD markedly enhanced cholesterol, inflammatory biomarkers in plasma and in the femoral arterial wall, and atherosclerotic lesions in the aortic arch; inflammation and atherosclerosis were further increased by photochemically generated oxygen radicals. Treatment with the NO-donating atorvastatin NCX 6560 (11.7 mg/kg) was significantly more effective than atorvastatin (10 mg/kg) in reducing the following parameters: lipid-rich lesions in the aortic arch (surface covered: atorvastatin = 24 ± 5%; NCX 6560 = 14.7 ± 3.9%; P< 0.05); the production of radical oxygen species in the aorta (dichlorofluorescein fluorescence intensity per milligram of protein: atorvastatin = 2419 ± 136.7; NCX 6560 = 1766 ± 161.2; P< 0.05); femoral artery intima/media thickness (atorvastatin = 1.2 ± 0.11; NCX 6560 = 0.3 ± 0.14; P< 0.05); circulating interleukin-6 (atorvastatin = 34.3 ± 6.8 pg/mL; NCX 6560 = 17.7 ± 14.4 pg/mL; P< 0.05); and matrix metalloproteinase 2 in the arterial wall (atorvastatin = 55.2 ± 1.9 ng/µg of proteins; NCX 6560 = 45.8 ± 2.6 ng/µg of proteins; P < 0.05). CONCLUSION In conditions of severe endothelial dysfunction, systemic peroxidation and inflammation, and accelerated atherosclerosis, atorvastatin, even at high doses, displays suboptimal anti-atherogenic and anti-inflammatory effects, while the addition of a NO-donating property confers enhanced anti-atherogenic and anti-inflammatory effects.

Lipid nanoparticles for brain targeting III. Long-term stability and in vivo toxicity

PURPOSE The aim of the work was to assess the long-term stability and the safety of lipid nanoparticles intended for brain drug delivery. METHODS Lipid nanoparticles, prepared by high pressure homogenization, were stored at room temperature and 4°C and monitored for their mean hydrodynamic diameter and Gaussian distribution width over time. Cetylpalmitate and polysorbate(®) 80 chemical integrity were investigated by nuclear magnetic resonance on diagnostic signals. Nanoparticle toxicity was assessed in chicken embryos by chorioallantoic membrane assay and in rodents by brain histological evaluation. RESULTS Data showed nanoparticle stability at 4°C over a period of time of 4 years with only a limited particle size increase while at room temperature destabilization was observed after 9 months. Nuclear magnetic resonance investigation confirmed the absence (<5%) of chemical degradation of the lipid matrix and the surfactant after 4 years of storage at 4°C. Chorioallantoic membrane assay and rat brain histology showed the absence of acute toxicity corroborating previously published data. CONCLUSIONS Cetylpalmitate nanoparticle long-term physical and chemical stability, together with the in vivo safety, corroborate the existing evidences of the high value of colloidal lipids as parenteral formulations and carriers for brain drug delivery.

Amyloid tumours in the soft tissues of the legs : Case report and review of the literature

Abstract We present a case of multiple amyloidomas occurring in the calves of a 61-year-old woman, without systemic amyloidosis or plasma cell dyscrasia. The disappearance of Congo red positivity after potassium permanganate treatment and immunohistochemical results showed that this was a case of reactive AA amyloidosis. True soft tissue amyloidomas are extremely rare, and this is the first case of AA amyloidoma in the soft tissues of the legs.

Distal intramural spread in colorectal cancer: a reappraisal of the extent of distal clearance in fifty cases.

Fifty colorectal carcinomas were Investigated to demonstrate distal intramural spread (DIS). In 17 cases (34 %) a DIS ranging from 0.25 to 3.5 cm was present. DIS was positively correlated with stage C2 (p < 0.01), lymph node metastasis (p < 0.03) and Infiltrative growth of the tumor (p < 0.05). Our results show that DIS is a relatively frequent event but of limited extension. In fact, a distal clearance margin of 2 cm was considered safe for all patients but one C2 mucoid case. No pathologic feature can predict preoperatively the presence and extent of DIS.

5-Fluorouracil carcinogenesis in BALB/c mice.

5-Fluorouracil, a drug mainly used in the treatment of gastrointestinal tract neoplasms, was administered i.p. to BALB/c mice at the dose of 30 mg/kg body weight once a week for 50 weeks to test its carcinogenicity. The treatment induced a significant increase in lung tumor in both sexes (males, p < 0.05; females, p < 0.01) and tumors of the lymphoreticular system in female mice (p < 0.001). These results suggest that 5-fluorouracil is carcinogenic in mice.

Human papilloma virus infection and Ki-ras oncogene in paraffin-embedded squamous carcinomas of the cervix.

42 paraffin-embedded squamous cervical carcinomas were screened for the presence of human papilloma virus (HPV; 6b, 11, 16, 18) and for activation of the Ki-ras oncogene family by polymerase chain reaction. In 72% of cases we found one or more HPV types, but no mutations of the Ki-ras gene (codon 12-1 and 61-1, 61-2 and 61-3) were found. We conclude that mutations of the Ki-ras oncogene, at the positions analyzed, are not likely to be involved in the events leading to cervical carcinogenesis.

Bilateral primary malignant lymphoma of the breast. A case report.

A case of bilateral primary malignant lymphoma of the breast in a 30 year old woman is described. The tumors were first discovered during a self-examination of the breast at the 7th month of pregnancy. Thereafter they rapidly increased in size. The patient underwent simple bilateral mastectomy, and histological examination revealed a centroblastic/centro-cytic lymphoma. The patient is alive and well 9 months after mastectomy.