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1.
Sci Total Environ ; 613-614: 409-417, 2018 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-28918272

RESUMO

This study presents a modelling system to evaluate the impact of weight reduction in light commercial vehicles with diesel engines on air quality and greenhouse gas emissions. The PROPS model assesses the emissions of one vehicle in the aforementioned category and its corresponding reduced-weight version. The results serve as an input to the RIAT+ tool, an air quality integrated assessment modelling system. This paper applies the tools in a case study in the Lombardy region (Italy) and discusses the input data pre-processing, the PROPS-RIAT+ modelling system runs, and the results.

2.
Clin Exp Rheumatol ; 25(5): 696-700, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-18078616

RESUMO

OBJECTIVES: Recent studies demonstrated in vivo the effectiveness of statins in reducing the inflammatory response in rheumatic diseases, and still more recently, simvastatin has been reported to inhibit in vitro IL-6 and IL-8 production by unstimulated fibroblast-like-synoviocytes (FLS) from rheumatoid arthritis (RA) patients. However, no data are available on the effect of statins on the production of these cytokines induced by IL-1, which plays a crucial role in joint inflammation in the course of active RA in vivo. METHODS: In 12 RA patients, synovial tissue specimens were taken to obtain cultures of FLS. Cultures were incubated with IL-1 +/- simvastatin (5-50 micromol/l), and IL-6 and IL-8 production was evaluated (ELISA), also following the addition of mevalonate and its isoprenoid derivatives. Moreover, nuclear factor-kB (NF-kB) activation (immunocytochemistry and Western Blot analysis) were also evaluated. RESULTS: Culture incubation with IL-1 produced a dramatic increase (up to 40-fold) in cytokine production with respect to unstimulated cells. Simvastatin significantly inhibited (about 20%) IL-6 and IL-8 production from IL-1-stimulated FLS. This effect was completely reverted by the concomitant incubation with mevalonate or geranylgeraniol (but not farnesol or squalene). Moreover, simvastatin produced a clear-cut inhibition of IL-1-induced NF-kB activation. CONCLUSION: Simvastatin significantly inhibits the production of IL-6 and IL-8 also in IL-1-stimulated FLS, even though to a lesser extent than in unstimulated cells, via a HMG-CoA-reductase block with an interference in prenylation process and NF-kB activation. Our results further support the rationale for the use of statins in the treatment of rheumatoid synovitis.


Assuntos
Artrite Reumatoide/metabolismo , Interleucina-1beta/farmacologia , Interleucina-6/metabolismo , Interleucina-8/metabolismo , NF-kappa B/metabolismo , Sinvastatina/farmacologia , Membrana Sinovial/metabolismo , Artrite Reumatoide/patologia , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Diterpenos/farmacologia , Feminino , Humanos , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Masculino , Ácido Mevalônico/farmacologia , Pessoa de Meia-Idade , Membrana Sinovial/citologia , Membrana Sinovial/efeitos dos fármacos , Membrana Sinovial/patologia
3.
Clin Exp Rheumatol ; 23(2): 205-12, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15895891

RESUMO

OBJECTIVE: Rheumatoid arthritis (RA) is a chronic inflammatory disease which involves the synovial membrane of multiple diarthroidal joints causing damage to cartilage and bones. The damage process seems to be related to an overproduction of oxygen reactive species inducing an oxidative perturbation. Since sulfhydryl groups are primary antioxidant factors, we were interested in investigating the balance of plasma sulfhydryl/disulfides in patients with active RA compared to healthy control subjects. METHODS: Twenty-one patients with RA and 15 age-matched controls were studied. Plasmatic sulfhydryl groups and their disulfide form concentrations were measured by spectrophotometry or HPLC. RESULTS: RA patients showed significantly lower levels of plasma protein sulfhydryls and cysteinyl-glycine compared to healthy controls (p < 0.001). Conversely, cystine and homocystine, and protein-bound cysteine and homocysteine were significantly increased (p < 0.005 in disulfides forms and p < 0.05 in protein mixed disulfides forms). There was a significant correlation between some clinical data (ESR, number of tender/swollen joints) and some of the parameters studied. CONCLUSION: The results of this study indicate a biochemical disturbance of plasma sulfhydryl/disulfides balance in patients with RA compared to controls with an increase in some oxidised forms (disulfides and protein mixed disulfides) and a decrease in free thiols. The increase in total homocysteine, correlated to the higher risk of cardiovascular diseases in RA patients, is associated with higher levels of the oxidised forms, disulfides and protein-thiol mixed disulfides.


Assuntos
Artrite Reumatoide/sangue , Compostos de Sulfidrila/sangue , Artrite Reumatoide/fisiopatologia , Dipeptídeos/sangue , Dissulfetos/sangue , Feminino , Homocistina/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Estresse Oxidativo
4.
J Biomol Struct Dyn ; 18(1): 155-68, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11021660

RESUMO

Geometry optimizations and energy calculations have been carried out via molecular orbital methods at the density functional B3LYP/LANL2DZ level on the molecules PO3-, OPO3(3-), HOPO3(2-), CH3OPO3(2-), H(CH3OPO3)-, O(PO3)2(4-), HO(PO3)2(3-), CH2(PO3)2(4-), (CH3OPO2)O(PO3)3-, O(PO3)3(5-), HO(PO3)3(4-), (PO3)3(3-), (CH3OPO2)O(PO3)2(4-), [Mg[O(PO3)2)]]2-, [Ca[O(PO3)2]]2-, [Ca[CH2(PO3)2]]2-, [Ca[CH3OPO2)O(PO3)]]-, [Ca(PO3)3]-, [Ca[O(PO3)3]]3-, and [Ca[CH3OPO2)O(PO3)2]]2- with the aim to find reliable and easily accessible computational methods to simulate some phosphate-containing molecules of importance for the living cells and to study the energetics for protonation and metal-complex formation reactions. The analysis is part of a general investigation on phosphate-containing molecules as potential dissolving agents for calcium pyrophosphate dihydrate (CPPD) crystals which deposit in certain articular diseases. The basis set was expanded to 6-31G** for the P atoms for all the molecules investigated and to 6-31G* for the O atoms for OPO3(3-). Calculations at the semiempirical MNDO/d level were also carried out for comparison purposes on the free ligand molecules and on [Mg[O(PO3)2]]2-. The density functional analysis reproduced well the geometry found at the solid state via X-ray diffraction. The analyses of the geometrical parameters and the total electronic energy of the molecules shows that O(PO3)2(4-) and other di- and tri-phosphates are versatile ligands for divalent metal ions like Ca2+. The computed P-O-P bond angle for free O(PO3)2(4-) is 180 degrees and the conformation of the two PO3- groupings is staggered along the P...P vector. The linear arrangement for P-O-P is assisted by P-O pi interactions. The bending of the P-O-P angle when accompanied by a slight P-O(b) elongation requires a very small amount of energy; 4.65 kcal/mol to pass from 180 to 140 degrees , as calculated at the DFT level. The computed Ca-O and Mg-O bond distances for [M[O(PO3)2]]2- are 2.378 and 2.079A, when the metal ions link two oxygen atoms from each PO3 group. The computed Ca-O bond lengths for [Ca[CH3OPO2)O(PO3)]]- are 2.482 (PalphaO2) and 2.358A (PbetaO2), showing a significant lengthening for Ca-OPalpha, when compared to the pyrophosphate derivative. The Ca-O bond lengths for [Ca[O(PO3)3]]3- and [Ca[CH3OPO2)O(PO3)2]]2- are 2.251A and 2.525 (PalphaO2), 2.407 and 2.338 (PbetaO2), and 2.251 and 2.228A (PgammaO2), showing a shortening for the Ca-OPgamma bond upon methylation. The (Pbeta)O-Pgamma bond length increases significantly (0.09 A) upon Ca(II) coordination to (CH3OPO2)O(PO3)2(4-) via all the three PO3 groups. This latter result suggests that metal complexes of linear organic-triphosphates have a larger tendency to release the PgammaO3 group when compared to the free ligand molecules. The electronic contribution to the energy of the complex formation reaction for [Ca[CH2(PO3)2]]2- is only slightly higher (some 1.8 kcal) than that for [Ca[O(PO3)2]]2-; but is much higher (some 63 kcal) than that relevant to the formation of [Ca[CH3OPO2)O(PO3)2]]2-. (ABSTRACT TRUNCATED)


Assuntos
Fosfatos de Cálcio/química , Condrocalcinose/metabolismo , Pirofosfato de Cálcio/química , Cristalização , Humanos , Técnicas In Vitro , Modelos Moleculares , Polifosfatos/química , Termodinâmica
6.
Rheumatology (Oxford) ; 46(7): 1161-4, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17478466

RESUMO

OBJECTIVES: To evaluate the long-term efficacy and safety of infliximab in patients with Behçet's disease (BD) and refractory bilateral posterior uveitis, and to assess the proportion of relapse-free subjects through months 12 and 24. METHODS: Open-label, multicentre, 24-month, prospective, follow up study on 12 consecutive patients with BD and refractory posterior uveitis who had failed at least one immunosuppressive drug. At baseline patients received prednisolone 1 mg/Kg/day with rapid tapering and nine infliximab infusions (5 mg/kg) over a 12-month period. Non-responders after the third infusion withdrew from the study. Patients were evaluated for ocular inflammation degree, visual acuity (VA), number of ocular attacks and incidence of adverse events (AEs). RESULTS: At 12-month visit, 9/12 (75%) patients achieved a complete remission with no relapse during the treatment period. All had a dramatic improvement of ocular inflammation after the first infusion, six were in complete remission after three infusions, and three after four. All these patients suspended corticosteroids at week 22. At 24-month visit, seven out of nine (78%) were still in remission. Mean VA improved from 0.2 +/- 0.6 to 0.5 +/- 0.2 (P < 0.001), and ocular attacks dropped from 40 in the year before therapy to 5 after infliximab cessation (P < 0.001). One patient had a partial remission with two relapses during treatment, and 2/12 (17%) patients showed no improvement. Infliximab was well tolerated with no serious AEs. CONCLUSIONS: Infliximab is rapidly effective and safe in a high proportion BD patients with refractory posterior uveitis, and may be helpful to prevent recurrences.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Síndrome de Behçet/tratamento farmacológico , Imunossupressores/uso terapêutico , Uveíte Posterior/tratamento farmacológico , Adulto , Análise de Variância , Síndrome de Behçet/complicações , Quimioterapia Combinada , Feminino , Seguimentos , Glucocorticoides/uso terapêutico , Humanos , Infliximab , Masculino , Pessoa de Meia-Idade , Prednisolona/uso terapêutico , Estudos Prospectivos , Estatísticas não Paramétricas , Resultado do Tratamento , Uveíte Posterior/complicações
7.
Boll Soc Ital Biol Sper ; 75(7-8): 47-53, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-11433678

RESUMO

Body temperature can modulate the pathogenesis of infectious, metabolic and autoimmune diseases. This effect has been attributed to several hypothesized mechanisms. Body temperature could play an important role in influencing some cellular functions of human white blood cells. In this work we examined the temperature effect on the respiratory burst in human neutrophils. Human polymorphonuclear leucocytes (PMN) were obtained from heparinized venous blood by dextran sedimentation and erythrocyte lysis with NH4Cl (0.87%). Granulocytes were stimulated with opsonized zymosan (OZ), formyl-methionyl-leucyl-phenylalanine (FMLP), phorbol myristate acetate (PMA), and monosodium urate (MSU) crystals at different temperatures (26, 37, 39, 40, 42 degrees C). The technique of luminol dependent chemiluminescence (CL) was used as indicator of oxygen free radicals (OFR) release by stimulated cells. OFR production from PMN stimulated with OZ, PMA, FMLP was higher at 37 degrees C than at 26, 39, 40, 42 degrees C (p < 0.001 OZ stimulated PMN at 40-42 degrees C; p < 0.05 PMA stimulated PMN at 42 degrees C. Significantly different from 37 degrees C value). OFR release from PMN stimulated with MSU crystals was significantly increased at 39 degrees C compared to 37 degrees C value (p < 0.001). This effect could not only be attributed to temperature influence on neutrophil activity. The specific polymorphonuclear leukocyte response to the microcrystals and the temperature influence on chemical and physical characteristics of the crystals may play an important role. We are now studying the temperature effect on activity of PMN exposed to others crystals.


Assuntos
Neutrófilos/efeitos dos fármacos , Explosão Respiratória/efeitos dos fármacos , Células Cultivadas , Radicais Livres/metabolismo , Humanos , N-Formilmetionina Leucil-Fenilalanina/farmacologia , Neutrófilos/citologia , Temperatura , Acetato de Tetradecanoilforbol/farmacologia , Zimosan/farmacologia
8.
Ann Rheum Dis ; 62(5): 460-4, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12695161

RESUMO

OBJECTIVE: To evaluate whether, in patients with the diffuse form of systemic sclerosis (dSSc), macrophage migration inhibitory factor (MIF) production is dysregulated. METHODS: 10 patients with dSSc and 10 healthy controls, matched for age and sex, were studied. MIF expression was evaluated by immunohistochemistry on formalin fixed skin biopsies of patients with dSSc and controls. MIF levels were assayed in the sera and in the supernatants of skin cultured fibroblasts by a colorimetric sandwich enzyme linked immunosorbent assay (ELISA). MIF concentrations in culture medium samples and in serum samples were compared by Student's two tailed t test for unpaired data. RESULTS: Anti-MIF antibody immunostained the basal and mainly suprabasal keratinocytes. Small perivascular clusters of infiltrating mononuclear cells were positive; scattered spindle fibroblast-like cells were immunostained in superficial and deep dermal layers. The serum concentrations of MIF in patients with dSSc (mean (SD) 10705.6 (9311) pg/ml) were significantly higher than in controls (2157.5 (1288.6) pg/ml; p=0.011); MIF levels from dSSc fibroblast cultures (mean (SD) 1.74 (0.16) ng/2 x 10(5) cells) were also significantly higher than in controls (0.6 (0.2) ng/2 x 10(5) cells; p=0.008). CONCLUSION: These results suggest that MIF may be involved in the amplifying proinflammatory loop leading to scleroderma tissue remodelling.


Assuntos
Fatores Inibidores da Migração de Macrófagos/análise , Escleroderma Sistêmico/metabolismo , Adulto , Idoso , Biópsia , Células Cultivadas/metabolismo , Ensaio de Imunoadsorção Enzimática/métodos , Feminino , Fibroblastos/metabolismo , Humanos , Imuno-Histoquímica/métodos , Fatores Inibidores da Migração de Macrófagos/sangue , Pessoa de Meia-Idade , Regulação para Cima
9.
Ann Rheum Dis ; 60(10): 962-7, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11557654

RESUMO

OBJECTIVE: To determine the dissolving ability (DA) of linear pentasodium tripolyphosphate (PSTP), cyclic trisodium metaphosphate (TSMP), polymeric sodium metaphosphate (SMP) on synthetic crystals of calcium pyrophosphate dihydrate (CPPD) and on crystalline aggregates of menisci from patients with chondrocalcinosis (CC). METHODS: Synthetic CPPD crystals were mixed with phosphate buffered saline (PBS), which contained the different polyphosphates, for one hour at 37 degrees C. The calcified menisci were obtained from the knees of four female patients with CPPD disease who underwent total arthroscopic meniscectomy for degenerative meniscal lesions. Meniscal cryosections and fragments were incubated in SMP (15 mg/ml PBS) at 37 degrees C for one hour and 24 hours, respectively. Histological evaluation on meniscal samples after polyphosphate incubation was carried out by ordinary transmitted light microscopy and polarised light microscopy. The dissolution of CPPD crystals by polyphosphates was assessed by atomic absorption spectroscopy, which determined the amount of calcium liberated from synthetic crystals and meniscal fragments. Cytotoxicity of SMP was evaluated by tetrazolium salt assay and by an ultrastructural study on cultured chondrocytes. RESULTS: SMP and PSTP showed higher DA on CPPD crystals than TSMP. Analysis of the DA values at increasing concentrations of SMP showed that a concentration of 15 mg/ml completely dissolved 2.0 mg CPPD crystals. The solution of meniscal CPPD crystals showed a significant increase of calcium concentration after three hours and 24 hours of SMP incubation (p=0.0001; Kruskal-Wallis analysis of variance) compared with fragments incubated in PBS control solution. Macroscopic and microscopic evaluation of meniscal specimens showed a notable reduction of CPPD deposits. A 50% inhibitory dose on cultured chondrocytes was reached at the maximum concentration of SMP used in this work (15 mg/ml); ultrastructural analysis did not show morphological alterations in the treated cells. CONCLUSION: The results of this study indicate that linear polyphosphates are effective in dissolving both synthetic and ex vivo CPPD crystal aggregates. This suggests a potential therapeutic use for these molecules in the treatment of symptomatic CC.


Assuntos
Pirofosfato de Cálcio/química , Condrocalcinose/metabolismo , Polifosfatos/química , Idoso , Análise de Variância , Condrócitos/ultraestrutura , Técnicas de Cultura , Feminino , Humanos , Concentração Inibidora 50 , Microscopia Eletrônica , Microscopia de Polarização , Pessoa de Meia-Idade , Solubilidade , Espectrofotometria Atômica , Estatísticas não Paramétricas
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