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71.
Dr. A. Conforti M. Donini G. Brocco P. Del Soldato G. Benoni L. Cuzzolin 《Inflammation research》1993,40(3-4):176-180
Diclofenac and its derivative nitrofenac were compared to test their anti-inflammatory efficacy and gastrointestinal toxicity in rats.A similar good anti-inflammatory activity of the two drugs was observed in carrageenan oedema and a marked gastrointestinal toxicity was induced by diclofenac, while nitrofenac failed to produce gastric damage even with very high doses (50 and 100 mg/kg).The lack of the gastric ulcers in rats treated with nitrofenac could be due to the absorption of the drug as an inactive inhibitor of PG synthesis and/or to the fact that probably nitric oxide is release in the intestine and plays an important protective role in maintaining the tissue integrity. 相似文献
72.
Inflammatory muscle diseases (IMD), including dermatomyositis (DM) and polymyositis (PM), affect skeletal muscle, leading to profound tissue modification. The etiology of IMD is unknown, but multiple steps of the disease pathogenesis have been identified. The main alterations involve the immune response. Cellular infiltrates found in the muscle provide strong evidence for the involvement of a preferential immune mechanism of muscle damage. The pathologic differences found between PM and DM indicate a different role played by cell-mediated and humoral immune alterations. It is well accepted that in the pathogenetic pathway both host genes and environmental factors are involved. Apoptosis, or programmed cell death, is a complex process that plays a key role in many physiological events. It regulates the turnover of immune cells and is one of the mechanisms involved in ensuring a competent, non-autoreactive repertoire of lymphocytes. Apoptosis as a mechanism of muscle fibre death has been described in several neuromuscular disorders and muscular dystrophies, and evidence of a lack of apoptosis in IMD suggests a failure of apoptotic clearance of inflammatory cells playing a role in the maintenance of chronic cytotoxic muscle fibre damage. Most likely, the failure of apoptosis seems to be the main hallmark of the pathogenesis of IMD. 相似文献
73.
Detection of human antibodies against Plasmodium falciparum sporozoites using synthetic peptides. 总被引:5,自引:1,他引:5 下载免费PDF全文
G Del Giudice A S Verdini M Pinori A Pessi J P Verhave C Tougne B Ivanoff P H Lambert H D Engers 《Journal of clinical microbiology》1987,25(1):91-96
A large peptide consisting of about 40 (Asn-Ala-Asn-Pro) repeats of Plasmodium falciparum circumsporozoite protein, (NANP)40, was synthesized. It was recognized specifically by monoclonal antibodies produced against P. falciparum sporozoites. Moreover, this peptide strongly inhibited the binding of such monoclonal antibodies to antigens present in a sporozoite extract. The (NANP)40 peptide was employed without any carrier to develop an enzyme-linked immunosorbent assay to detect sporozoite-specific serum antibodies arising after natural malaria infections. Antibodies were detected in a high percentage (43.1%) of European patients suffering from acute P. falciparum malaria and in Africans living in an area of Gabon endemic for malaria. In the latter group, the frequency of antisporozoite antibodies increased with age, reaching 65.9% in individuals more than 40 years old. There was a significant correlation between the results obtained with an immunofluorescence assay with glutaraldehyde-fixed sporozoites and those obtained by enzyme-linked immunosorbent assay with (NANP)40. Therefore, such synthetic peptides representing the repetitive epitope of P. falciparum circumsporozoite protein can be used for the detection of antisporozoite antibodies and for the epidemiological studies required to obtain base-line data concerning the immune status of individuals before their participation in a sporozoite vaccine trial. 相似文献
74.
Giuseppe A. Ramirez Valentina Canti Stefania Del Rosso Roberta Erra Lucia Moiola Marco Magnoni 《Autoimmunity》2020,53(1):21-27
AbstractBackground: Systemic lupus erythematosus (SLE) is associated with a constellation of complications affecting multiple organs, including neuropsychiatric manifestations (NPSLE) and ischaemic events, leading to increased long-term morbidity. Antiphospholipid antibodies (aPL) are a major determinant of vascular inflammation and thromboembolic risk. The diagnostic role of anti-phosphatidylserine/prothrombin (aPS/PT) antibodies in this setting is incompletely defined.Aim: To verify whether aPS/PT add to diagnostics and disease stratification in patients with SLE with or without other aPL.Methods: 131 consecutive patients were studied, including 20 patients with SLE and secondary antiphospholipid syndrome (APS). aPS/PT IgG and IgM were assessed through ELISA and patients were stratified based on the presence of other aPL, on their clinical and laboratory features at time of blood sampling and on their clinical history. Synthetic indices of disease activity, chronic damage and cardiovascular risk were calculated at time of venipuncture.Results: Fifty-one (38.9%) patients with SLE had aPS/PT and 15 (11.5%) patients had aPS/PT as the only aPL (aPS/PT-only). aPS/PT-only patients had a significantly higher prevalence of NPSLE than quadruple aPL-negative patients (p?=?.007). Patients with aPS/PT were more likely to have a history of ischaemia, thrombocytopenia and Libman–Sacks’ endocarditis. The presence of aPS/PT also associated with previous accrual of at least one damage item (p?=?.043), but had limited predictive values for damage progression in the short term.Conclusion: aPS/PT antibodies provide non-redundant information that could contribute to risk assessment and stratification of patients with SLE. 相似文献
75.
Neuroprotective effects of IGF-I against TNFalpha-induced neuronal damage in HIV-associated dementia
Ying Wang J Peruzzi F Lassak A Del Valle L Radhakrishnan S Rappaport J Khalili K Amini S Reiss K 《Virology》2003,305(1):66-76
Human immunodeficiency virus type 1 (HIV-1) infection often results in disorders of the central nervous system, including HIV-associated dementia (HAD). It is suspected that tumor necrosis factor-alpha (TNFalpha) released by activated and/or infected macrophages/microglia plays a role in the process of neuronal damage seen in AIDS patients. In light of earlier studies showing that the activation of the insulin-like growth factor I receptor (IGF-IR) exerts a strong neuroprotective effect, we investigated the ability of IGF-I to protect neuronal cells from HIV-infected macrophages. Our results demonstrate that the conditioned medium from HIV-1-infected macrophages, HIV/CM, causes loss of neuronal processes in differentiated PC12 and P19 neurons and that these neurodegenerative effects are associated with the presence of TNFalpha. Furthermore, we demonstrate that IGF-I rescues differentiated neurons from both HIV/CM and TNFalpha-induced damage and that IGF-I-mediated neuroprotection is strongly enhanced by overexpression of the wt IGF-IR cDNA and attenuated by the antisense IGF-IR cDNA. Finally, IGF-I-mediated antiapoptotic pathways are continuously functional in differentiated neurons exposed to HIV/CM and are likely supported by TNFalpha-mediated phosphorylation of I(kappa)B. All together these results suggest that the balance between TNFalpha and IGF-IR signaling pathways may control the extent of neuronal injury in this HIV-related experimental setting. 相似文献
76.
Bjarnarson SP Jakobsen H Del Giudice G Trannoy E Siegrist CA Jonsdottir I 《European journal of immunology》2005,35(4):1037-1045
The aim of vaccination is to rapidly elicit protective immunity and generate memory for sustained protection. We studied the induction and persistence of polysaccharide (PS)-specific memory in neonatal and infant mice primed with pneumococcal conjugate (Pnc1-TT) by assessing the response to native pneumococcal PS (PPS-1), the kinetics of the PPS-1-specific IgG response to a second Pnc1-TT dose and affinity maturation. A subcutaneous (s.c.) Pnc1-TT booster induced a rapid increase in PPS-1-specific IgG, indicating efficient priming for memory by a single dose of Pnc1-TT already at 1 week of age. High levels were maintained for >12 weeks. However, a PPS-1 booster induced no response in neonatal or infant mice. The adjuvant LT-K63 significantly enhanced the IgG response and affinity to Pnc1-TT by both the s.c. and the intranasal (i.n.) route in all age groups. In neonatal and infant mice, PPS-1 and LT-K63 induced a booster response only when given i.n. following either s.c. or i.n. priming with Pnc1-TT and LT-K63. In contrast, PPS-1 with or without LT-K63 administered s.c. compromised the ongoing PPS-1-specific response elicited in neonatal mice by either s.c. or i.n. priming with Pnc1-TT and LT-K63. These results demonstrate the advantage of the mucosal route for elicitation of PS-specific memory responses in early life. 相似文献
77.
Enhancement of protective efficacy following intranasal immunization with vaccine plus a nontoxic LTK63 mutant delivered with nanoparticles 总被引:8,自引:0,他引:8
Baudner BC Balland O Giuliani MM Von Hoegen P Rappuoli R Betbeder D Del Giudice G 《Infection and immunity》2002,70(9):4785-4790
Most vaccines are still given parenterally. Mucosal vaccination would offer different advantages over parenteral immunization, including blocking of the pathogens at the portal of entry. In this paper, nontoxic Escherichia coli heat-labile enterotoxin (LT) mutants and Supramolecular Biovector systems (SMBV) were evaluated in mice as mucosal adjuvants and delivery systems, respectively, for intranasal immunization with the conjugated group C meningococcal vaccine. The conjugated vaccine formulated together with the LT mutants and the SMBV induced very high titers of serum and mucosal antibodies specific for the group C meningococcal polysaccharide. This vaccination strategy also induced high titers of antibodies with bactericidal activity, which is known to correlate with efficacy. Importantly, the mucosal vaccination, but not the conventional parenteral vaccination, induced bactericidal antibodies at the mucosal level. These data strongly support the feasibility of development of intranasal vaccines with an enhanced protective efficacy against meningococci and possibly against other encapsulated bacteria. 相似文献
78.
Harrath R Bourlet T Delézay O Douche-Aourik F Omar S Aouni M Pozzetto B 《Journal of medical virology》2004,74(2):283-290
Although the transmission of coxsackievirus B3 occurs mainly via the oral route, little is known about the primary replication and persistence of this agent in the intestine. To address this question, BALB/c mice were inoculated by gavage with coxsackievirus B3, Nancy strain. The mice were killed from 1 hr to 90 days after infection. The viral markers were detected in the small intestine using RT-PCR, cell culture and detection of VP1 protein. Coxsackievirus B3 was detected positive by the three methods from hr 2 to day 45 after infection. By using monoclonal antibodies directed towards VP1, CD40 and CD26, the virus was shown to be present in the lymphocytes of the mucosa as soon as 2 hr after infection; in contrast, no virus was detected in the epithelial cells lining the intestinal lumen. Further experiments were performed to evaluate the capacity of coxsackievirus B3 to establish a persistent infection in two intestinal cell lines. In contrast to HT29 cells, the CaCo-2 cells were shown to develop a persistent infection for up to 20 passages, as demonstrated by the detection of viral RNA and VP1 protein. This study provides further evidence that, after infection by the oral route, the viral particles are concentrated in the lymphocytes of the mucosal layer. In addition, the results suggest that coxsackievirus B3 is capable of establishing a persistent infection in the small intestine that may act as a reservoir of viral particles for the delayed spread of the virus to other target organs. 相似文献
79.
80.
Gómez-Román JJ Del Valle CE Zarrabeitia MT Martínez JC Goñi FZ Lera RM Cuevas J Val-Bernal JF 《Pathology international》2005,55(9):580-584
Bronchioloalveolar carcinoma is a distinctive subtype of pulmonary adenocarcinoma, without effective therapy, although there have recently been some attempts to use lung transplantation. However, a high post-transplantation local recurrence rate is described with some controversy regarding the possible involved mechanisms, the main possibilities being the lymphatic spread and aerosolization. Presented herein is a case of a bilateral lung transplantation for a bilateral and pneumonic form of non-mucinous bronchioloalveolar carcinoma in a 43-year-old woman. The histological analysis of mediastinal lymph nodes during surgery did not show neoplastic cells. Thirty-five months after transplantation several nodular opacities in donor lungs were detected. Three pulmonary wedge resections were performed showing a non-mucinous bronchioloalveolar carcinoma with the same histological characteristics as the primary. Again, the mediastinal lymph nodes were tumor free. A complete microsatellites molecular analysis was performed to compare the primary and recurrent carcinoma using capillary electrophoresis, showing that the recurrent tumor was generated in a recipient cellular clone. The absence of lymph node metastasis and the molecular evidence of the recipient origin of the neoplasm supports the contamination of the new lungs at the time of implantation as being the reason for the high incidence of recurrence after lung transplantation in this kind of disease. 相似文献