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2.
Nanotoxicology ; 10(6): 720-7, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-26581431

RESUMO

Nanoparticle (NP) pharmacokinetics and biological effects are influenced by many factors, especially surface physicochemical properties. We assessed the effects of an amorphous silica coating on the fate of zinc after intravenous (IV) injection of neutron activated uncoated (65)ZnO or silica-coated (65)ZnO NPs in male Wistar Han rats. Groups of IV-injected rats were sequentially euthanized, and 18 tissues were collected and analyzed for (65)Zn radioactivity. The protein coronas on each ZnO NP after incubation in rat plasma were analyzed by SDS-PAGE gel electrophoresis and mass spectrometry of selected gel bands. Plasma clearance for both NPs was biphasic with rapid initial and slower terminal clearance rates. Half-lives of plasma clearance of silica-coated (65)ZnO were shorter (initial - <1 min; terminal - 2.5 min) than uncoated (65)ZnO (initial - 1.9 min; terminal - 38 min). Interestingly, the silica-coated (65)ZnO group had higher (65)Zn associated with red blood cells and higher initial uptake in the liver. The (65)Zn concentrations in all the other tissues were significantly lower in the silica-coated than uncoated groups. We also found that the protein corona formed on silica-coated ZnO NPs had higher amounts of plasma proteins, particularly albumin, transferrin, A1 inhibitor 3, α-2-hs-glycoprotein, apoprotein E and α-1 antitrypsin. Surface modification with amorphous silica alters the protein corona, agglomerate size, and zeta potential of ZnO NPs, which in turn influences ZnO biokinetic behavior in the circulation. This emphasizes the critical role of the protein corona in the biokinetics, toxicology and nanomedical applications of NPs.


Assuntos
Proteínas Sanguíneas/metabolismo , Nanopartículas/química , Dióxido de Silício/sangue , Dióxido de Silício/química , Óxido de Zinco/sangue , Óxido de Zinco/química , Animais , Eletroforese em Gel de Poliacrilamida , Cinética , Masculino , Taxa de Depuração Metabólica , Nanopartículas/análise , Coroa de Proteína/metabolismo , Ratos , Ratos Wistar , Propriedades de Superfície
3.
Part Fibre Toxicol ; 12: 31, 2015 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-26458946

RESUMO

BACKGROUND: The physicochemical properties of nanoparticles (NPs) influence their biological outcomes. METHODS: We assessed the effects of an amorphous silica coating on the pharmacokinetics and pulmonary effects of CeO2 NPs following intratracheal (IT) instillation, gavage and intravenous injection in rats. Uncoated and silica-coated CeO2 NPs were generated by flame spray pyrolysis and later neutron-activated. These radioactive NPs were IT-instilled, gavaged, or intravenously (IV) injected in rats. Animals were analyzed over 28 days post-IT, 7 days post-gavage and 2 days post-injection. RESULTS: Our data indicate that silica coating caused more but transient lung inflammation compared to uncoated CeO2. The transient inflammation of silica-coated CeO2 was accompanied by its enhanced clearance. Then, from 7 to 28 days, clearance was similar although significantly more (141)Ce from silica-coated (35%) was cleared than from uncoated (19%) (141)CeO2 in 28 days. The protein coronas of the two NPs were significantly different when they were incubated with alveolar lining fluid. Despite more rapid clearance from the lungs, the extrapulmonary (141)Ce from silica-coated (141)CeO2 was still minimal (<1%) although lower than from uncoated (141)CeO2 NPs. Post-gavage, nearly 100% of both NPs were excreted in the feces consistent with very low gut absorption. Both IV-injected (141)CeO2 NP types were primarily retained in the liver and spleen. The silica coating significantly altered the plasma protein corona composition and enhanced retention of (141)Ce in other organs except the liver. CONCLUSION: We conclude that silica coating of nanoceria alters the biodistribution of cerium likely due to modifications in protein corona formation after IT and IV administration.


Assuntos
Cério/química , Nanopartículas Metálicas , Dióxido de Silício/química , Animais , Cinética , Microscopia Eletrônica , Ratos , Distribuição Tecidual
4.
Ann Rheum Dis ; 72(10): 1613-20, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23687260

RESUMO

OBJECTIVES: To compare the efficacy and safety of innovator infliximab (INX) and CT-P13, an INX biosimilar, in active rheumatoid arthritis patients with inadequate response to methotrexate (MTX) treatment. METHODS: Phase III randomised, double-blind, multicentre, multinational, parallel-group study. Patients with active disease despite MTX (12.5-25 mg/week) were randomised to receive 3 mg/kg of CT-P13 (n=302) or INX (n=304) with MTX and folic acid. The primary endpoint was the American College of Rheumatology 20% (ACR20) response at week 30. Therapeutic equivalence of clinical response according to ACR20 criteria was concluded if the 95% CI for the treatment difference was within ±15%. Secondary endpoints included ACR response criteria, European League Against Rheumatism (EULAR) response criteria, change in Disease Activity Score 28 (DAS28), Medical Outcomes Study Short-Form Health Survey (SF-36), Simplified Disease Activity Index, Clinical Disease Activity Index, as well as pharmacokinetic (PK) and pharmacodynamic (PD) parameters, safety and immunogenicity. RESULTS: At week 30, ACR20 responses were 60.9% for CT-P13 and 58.6% for INX (95% CI -6% to 10%) in the intention-to-treat population. The proportions in CT-P13 and INX groups achieving good or moderate EULAR responses (C reactive protein (CRP)) at week 30 were 85.8% and 87.1%, respectively. Low disease activity or remission according to DAS28-CRP, ACR-EULAR remission rates, ACR50/ACR70 responses and all other PK and PD endpoints were highly similar at week 30. Incidence of drug-related adverse events (35.2% vs 35.9%) and detection of antidrug antibodies (48.4% vs 48.2%) were highly similar for CT-P13 and INX, respectively. CONCLUSIONS: CT-P13 demonstrated equivalent efficacy to INX at week 30, with a comparable PK profile and immunogenicity. CT-P13 was well tolerated, with a safety profile comparable with that of INX. CLINICALTRIALS.GOV IDENTIFIER: NCT01217086.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Antirreumáticos/uso terapêutico , Artrite Reumatoide/tratamento farmacológico , Imunoglobulina G/uso terapêutico , Metotrexato/uso terapêutico , Adolescente , Adulto , Idoso , Anticorpos Monoclonais/efeitos adversos , Anticorpos Monoclonais/sangue , Antirreumáticos/efeitos adversos , Antirreumáticos/sangue , Artrite Reumatoide/sangue , Método Duplo-Cego , Quimioterapia Combinada , Feminino , Humanos , Imunoglobulina G/efeitos adversos , Imunoglobulina G/sangue , Infliximab , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Resultado do Tratamento , Adulto Jovem
5.
Clin Rheumatol ; 31(5): 829-34, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22281876

RESUMO

Hereditary periodic fever syndromes (HPFS) are rare genetic diseases characterized by recurrent episodes of inflammation. Little information is available concerning HPFS in Latin American Hispanic population. The purpose of this study was to determine the clinical and genetic features of HPFS in Chilean population. A multicenter retrospective study of Hispanic Chilean patients with genetically confirmed HPFS was performed. We included 13 patients, 8 with familial Mediterranean fever (FMF) and 5 with TNF receptor-associated periodic syndrome (TRAPS), evaluated at rheumatology or pediatric rheumatology clinics between January 2007 and December 2010. Median age of symptoms onset was 8 years (range 1-35) and 8 years (range 0.3-21) for FMF and TRAPS, respectively. Median duration of fever was 3 days (range 2.5-15) for FMF and 21 days (range 9.5-30) for TRAPS. Genotyping of the MEFV gene in FMF patients revealed a homozygous M694V missense mutation in one patient, and heterozygous missense mutations in seven patients: M694V (n = 3), E148Q, R717H, A744S, and A511V. Sequencing of the TNFRSF1A gene in TRAPS patients revealed heterozygous missense mutations in four patients: T50M, C30R, R92Q, and IVS3+30:G→A, and a two-base pair deletion (IVS2-17_18del2bpCT) in one patient. Mutation in MEFV R717H and mutations in TNFRSF1A IVS2-17_18del2bpCT and IVS3+30:G→A are novel and have not been described previously. This study reports the largest series of genetically confirmed HPFS in Latin America, and adds evidence regarding the clinical and genetic characteristics of patients with FMF and TRAPS in Hispanic population. Mutations identified in MEFV and TNFRSF1A genes include defects reported in other ethnicities and novel mutations.


Assuntos
Proteínas do Citoesqueleto/genética , Febre Familiar do Mediterrâneo , Predisposição Genética para Doença , Mutação de Sentido Incorreto , Receptores Tipo I de Fatores de Necrose Tumoral/genética , Adolescente , Adulto , Criança , Pré-Escolar , Chile/epidemiologia , Análise Mutacional de DNA , Febre Familiar do Mediterrâneo/epidemiologia , Febre Familiar do Mediterrâneo/genética , Febre Familiar do Mediterrâneo/patologia , Feminino , Humanos , Lactente , Masculino , Pirina , Recidiva , Estudos Retrospectivos , Adulto Jovem
6.
Lancet ; 377(9767): 721-31, 2011 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-21296403

RESUMO

BACKGROUND: Systemic lupus erythematosus is a heterogeneous autoimmune disease that is associated with B-cell hyperactivity, autoantibodies, and increased concentrations of B-lymphocyte stimulator (BLyS). The efficacy and safety of the fully human monoclonal antibody belimumab (BLyS-specific inhibitor) was assessed in patients with active systemic lupus erythematosus. METHODS: Patients (aged ≥18 years) who were seropositive with scores of at least 6 on the Safety of Estrogens in Lupus Erythematosus National Assessment-Systemic Lupus Erythematosus Disease Activity Index (SELENA-SLEDAI) were enrolled in a multicentre phase 3 study, which was done in Latin America, Asia-Pacific, and eastern Europe. Patients were randomly assigned by use of a central interactive voice response system in a 1:1:1 ratio to belimumab 1 mg/kg or 10 mg/kg, or placebo by intravenous infusion in 1 h on days 0, 14, and 28, and then every 28 days until 48 weeks, with standard of care. Patients, investigators, study coordinators, and sponsors were masked to treatment assignment. Primary efficacy endpoint was improvement in the Systemic Lupus Erythematosus Responder Index (SRI) at week 52 (reduction ≥4 points in SELENA-SLEDAI score; no new British Isles Lupus Assessment Group [BILAG] A organ domain score and no more than 1 new B organ domain score; and no worsening [<0·3 increase] in Physician's Global Assessment [PGA] score) versus baseline. Method of analysis was by modified intention to treat. This trial is registered with ClinicalTrials.gov, number NCT00424476. FINDINGS: 867 patients were randomly assigned to belimumab 1 mg/kg (n=289) or 10 mg/kg (n=290), or placebo (n=288). 865 were treated and analysed in the belimumab (1 mg/kg, n=288; 10 mg/kg, n=290) and placebo groups (n=287). Significantly higher SRI rates were noted with belimumab 1 mg/kg (148 [51%], odds ratio 1·55 [95% CI 1·10-2·19]; p=0·0129) and 10 mg/kg (167 [58%], 1·83 [1·30-2·59]; p=0·0006) than with placebo (125 [44%]) at week 52. More patients had their SELENA-SLEDAI score reduced by at least 4 points during 52 weeks with belimumab 1 mg/kg (153 [53%], 1·51 [1·07-2·14]; p=0·0189) and 10 mg/kg (169 [58%], 1·71 [1·21-2·41]; p=0·0024) than with placebo (132 [46%]). More patients given belimumab 1 mg/kg (226 [78%], 1·38 [0·93-2·04]; p=0·1064) and 10 mg/kg (236 [81%], 1·62 [1·09-2·42]; p=0·0181) had no new BILAG A or no more than 1 new B flare than did those in the placebo group (210 [73%]). No worsening in PGA score was noted in more patients with belimumab 1 mg/kg (227 [79%], 1·68 [1·15-2·47]; p=0·0078) and 10 mg/kg (231 [80%], 1·74 [1·18-2·55]; p=0·0048) than with placebo (199 [69%]). Rates of adverse events were similar in the groups given belimumab 1 mg/kg and 10 mg/kg, and placebo: serious infection was reported in 22 (8%), 13 (4%), and 17 (6%) patients, respectively, and severe or serious hypersensitivity reactions on an infusion day were reported in two (<1%), two (<1%), and no patients, respectively. No malignant diseases were reported. INTERPRETATION: Belimumab has the potential to be the first targeted biological treatment that is approved specifically for systemic lupus erythematosus, providing a new option for the management of this important prototypic autoimmune disease. FUNDING: Human Genome Sciences and GlaxoSmithKline.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Fatores Imunológicos/uso terapêutico , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Doença Aguda , Adulto , Idoso , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/efeitos adversos , Anticorpos Monoclonais Humanizados , Esquema de Medicação , Feminino , Humanos , Fatores Imunológicos/administração & dosagem , Fatores Imunológicos/efeitos adversos , Modelos Logísticos , Lúpus Eritematoso Sistêmico/diagnóstico , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Inquéritos e Questionários , Resultado do Tratamento
8.
Bol. Hosp. Viña del Mar ; 42(2): 89-92, 1986.
Artigo em Espanhol | LILACS | ID: lil-104063

RESUMO

Se estudiaron 9 pacientes portadores de Poliarteritis Nodosa diagnosticada durante un período de 9 años en el Hospital del Salvador de Santiago. Los síntomas de presentación fueron inespecíficos en la mayoría e inclcuyeron compromiso del estado general, fiebre, baja de peso y nódulos cutáneos. También hubo compromiso renal y ocular. El tiempo promedio entre el inicio de la enfermedad y el diagnóstico fue de 9.8 meses. El diagnóstico tardío de la enfermedad en esta serie parece estar relacionado con la inespecificidad de los síntomas clínicos. La mortalidad fue 22% que es similar a la descrita en la literatura


Assuntos
Adulto , Pessoa de Meia-Idade , Humanos , Poliarterite Nodosa/fisiopatologia , Ciclofosfamida/uso terapêutico , Poliarterite Nodosa/tratamento farmacológico , Prednisona/uso terapêutico
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