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1.
PLoS One ; 9(3): e90838, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24621561

RESUMO

Case reports of patients with mal-functioning metal-on-metal hip replacement (MoMHR) prostheses suggest an association of elevated circulating metal levels with visual and auditory dysfunction. However, it is unknown if this is a cumulative exposure effect and the impact of prolonged low level exposure, relevant to the majority of patients with a well-functioning prosthesis, has not been studied. Twenty four male patients with a well-functioning MoMHR and an age and time since surgery matched group of 24 male patients with conventional total hip arthroplasty (THA) underwent clinical and electrophysiological assessment of their visual and auditory health at a mean of ten years after surgery. Median circulating cobalt and chromium concentrations were higher in patients after MoMHR versus those with THA (P<0.0001), but were within the Medicines and Healthcare Products Regulatory Agency (UK) investigation threshold. Subjective auditory tests including pure tone audiometric and speech discrimination findings were similar between groups (P>0.05). Objective assessments, including amplitude and signal-to-noise ratio of transient evoked and distortion product oto-acoustic emissions (TEOAE and DPOAE, respectively), were similar for all the frequencies tested (P>0.05). Auditory brainstem responses (ABR) and cortical evoked response audiometry (ACR) were also similar between groups (P>0.05). Ophthalmological evaluations, including self-reported visual function by visual functioning questionnaire, as well as binocular low contrast visual acuity and colour vision were similar between groups (P>0.05). Retinal nerve fibre layer thickness and macular volume measured by optical coherence tomography were also similar between groups (P>0.05). In the presence of moderately elevated metal levels associated with well-functioning implants, MoMHR exposure does not associate with clinically demonstrable visual or auditory dysfunction.


Assuntos
Audição , Prótese de Quadril/efeitos adversos , Metais , Visão Ocular , Estudos Transversais , Seguimentos , Saúde , Humanos , Masculino , Metais/sangue , Pessoa de Meia-Idade
3.
Curr Med Res Opin ; 23(12): 3069-78, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17971283

RESUMO

OBJECTIVES: To evaluate the cost-effectiveness of etoricoxib, a cyclooxygenase (COX)-2 selective inhibitor, versus non-selective nonsteroidal anti-inflammatory drugs (nsNSAIDs) in the treatment of ankylosing spondylitis (AS). METHODS: The cost-effectiveness of etoricoxib versus nsNSAIDs was evaluated from the UK National Health Service (NHS) and society perspective with a decision-analytic model. Patients stayed on initial therapy throughout 52 weeks unless they experienced an adverse event (AE) or lacked efficacy, in which case they switched to another nsNSAID or a tumor necrosis factor alpha antagonist. Efficacy data were obtained from a 1-year etoricoxib clinical trial in AS. Bath AS Functional Index (BASFI) data were translated into Quality Adjusted Life Year (QALY) weights using a published data on the relation between BASFI and Short-form (SF) 36 Quality of life scores, as well as the relation between SF-36 and utility. Safety data were based on meta-analyses of etoricoxib trials. Information on treatment pathways, resource consumption, and absenteeism from work was obtained from literature and experts. Model outcomes included QALYs, perforations, ulcers, or bleeds, cardiovascular events, and costs. RESULTS: Etoricoxib was cost-effective compared to nsNSAIDs in terms of cost per QALY saved ( pound5611). Probabilistic sensitivity analysis found a 77% probability of the incremental cost per QALY saved being within a threshold for cost-effectiveness of pound20 000. The expected direct costs over the 52-week period were pound1.23 (95% uncertainty distribution pound1.10; pound1.39) and pound1.13 per day ( pound0.78; pound1.55) for patients starting with etoricoxib and nsNSAIDs, respectively. When costs related to absenteeism were taken into account, the cost per QALY saved was pound281. CONCLUSIONS: Given the underlying assumptions and data used, this economic evaluation demonstrated that, compared to nsNSAIDs, etoricoxib is a cost-effective therapy for AS patients in the UK.


Assuntos
Anti-Inflamatórios não Esteroides/economia , Inibidores de Ciclo-Oxigenase/economia , Piridinas/economia , Espondilite Anquilosante/tratamento farmacológico , Sulfonas/economia , Anti-Inflamatórios não Esteroides/uso terapêutico , Análise Custo-Benefício , Inibidores de Ciclo-Oxigenase/uso terapêutico , Custos de Medicamentos , Etoricoxib , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Piridinas/uso terapêutico , Sulfonas/uso terapêutico , Resultado do Tratamento , Reino Unido
4.
J Leukoc Biol ; 78(1): 266-78, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15817701

RESUMO

Tumor necrosis factor alpha (TNF-alpha) is a potent, pleiotrophic cytokine, which is proinflammatory but can also suppress T lymphocyte function. In chronic inflammatory disease such as rheumatoid arthritis, exposure of T cells to TNF-alpha alters their ability to mount a response by modulating the T cell receptor (TCR) signaling pathway, but the mechanisms involved remain obscure. Here, we investigated the specific role of TNF receptor 1 (TNFR1) signaling in the modulation of the TCR signaling pathway. We observed a down-regulation of the intracellular calcium ([Ca(2+)](i)) signal in Jurkat T cells after just 30 min exposure to TNF-alpha, and maximum suppression was reached after 3 h. This effect was transient, and signals returned to normal after 12 h. This depression of [Ca(2+)](i) was also observed in human CD4+ T lymphocytes. The change in Ca(2+) signal was related to a decrease in the plasma membrane Ca(2+) influx, which was apparent even when the TCR signal was bypassed using thapsigargin to induce a Ca(2+) influx. The role of TNF-alpha-induced activation of the sphingolipid cascade in this pathway was examined. The engagement of TNFR1 by TNF-alpha led to a time-dependent increase in acid sphingomyelinase (SMase; ASM) activity, corresponding with a decrease in cellular sphingomyelin. In parallel, there was an increase in cellular ceramide, which correlated directly with the decrease in the magnitude of the Ca(2+) response to phytohemagglutinin. Exogenous addition of SMase or ceramide mimicked the effects of TNFR1 signals on Ca(2+) responses in Jurkat T cells. Direct evidence for the activation of ASM in this pathway was provided by complete abrogation of the TNF-alpha-induced inhibition of the Ca(2+) influx in an ASM-deficient murine T cell line (OT-II(+/+)ASM(-/-)). This potent ability of TNF-alpha to rapidly modulate the TCR Ca(2+) signal via TNFR1-induced ASM activation can explain its suppressive effect on T cell function. This TNFR1 signaling pathway may play a role as an important regulator of T cell responses.


Assuntos
Sinalização do Cálcio/imunologia , Cálcio/metabolismo , Receptores de Antígenos de Linfócitos T/metabolismo , Receptores Tipo I de Fatores de Necrose Tumoral/metabolismo , Esfingomielina Fosfodiesterase/metabolismo , Anticorpos Monoclonais/farmacologia , Complexo CD3/imunologia , Complexo CD3/metabolismo , Canais de Cálcio/metabolismo , Sinalização do Cálcio/efeitos dos fármacos , Ceramidas/farmacologia , Ativação Enzimática/imunologia , Humanos , Células Jurkat , Lisofosfolipídeos/metabolismo , Fito-Hemaglutininas/farmacologia , Esfingomielina Fosfodiesterase/farmacologia , Esfingosina/análogos & derivados , Esfingosina/metabolismo , Linfócitos T/efeitos dos fármacos , Linfócitos T/metabolismo , Fator de Necrose Tumoral alfa/farmacologia
5.
FEBS Lett ; 579(6): 1539-44, 2005 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-15733870

RESUMO

Persistent tumour necrosis factor alpha (TNF-alpha) exposure uncouples proximal T-cell receptor (TCR)-signalling events. Here, we demonstrate that chronic TNF-alpha exposure also attenuates signalling distal to the TCR, by specifically inhibiting Ca2+ influx evoked by thapsigargin in CD4+ T-cells. Mitogen-induced Ca2+ responses were impaired in a dose dependent manner, and TCR-induced Ca2+ responses were also significantly reduced. The impairment of Ca2+ influx strongly correlated with poor function as proliferative responses to both mitogen and anti-CD3/CD28 stimulation were suppressed. Our findings show that persistent TNF-alpha exposure of T-cells specifically inhibits store operated Ca2+ influx. This may affect gene activation and contribute to the poor T-cell function in chronic inflammatory disease.


Assuntos
Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/metabolismo , Sinalização do Cálcio/efeitos dos fármacos , Cálcio/metabolismo , Fator de Necrose Tumoral alfa/farmacologia , Anticorpos/imunologia , Complexo CD3/metabolismo , Canais de Cálcio/metabolismo , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Humanos
9.
J Am Soc Nephrol ; 15(3): 717-21, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-14978174

RESUMO

UNLABELLED: Tumor necrosis factor alpha (TNFalpha) plays an important role in the pathogenesis of anti-neutrophil cytoplasmic antibody-associated systemic vasculitis. TNFalpha blockade is a potential therapy for these disorders. METHODS: An open-label, multi-center, prospective clinical trial in two subgroups was performed. Study I examined acute disease, either first presentation or relapse (Birmingham Vasculitis Activity Score [BVAS] > or = 10; n = 16); study II examined persistent disease (BVAS > or = 4; n = 16). Patients received infliximab (5 mg/kg) at 0, 2, 6, and 10 wk. Concomitant therapy in study I included prednisolone and cyclophosphamide. Study II patients continued their existing treatment regimens, with prednisolone tapered according to clinical status. RESULTS: Mean age was 52.4 yr, 53% of the patients were female, and follow-up was 16.8 mo. Twenty-eight patients (88%) achieved remission (14 per study group). BVAS decreased from 12.3 (confidence interval [CI] = 10.5 to 14.0) at entry to 0.3 (CI = 0.2 to 0.9) at wk 14 (P < 0.001). C-reactive protein (mg/L) decreased from 29.4 (CI = 16.8 to 42.0) at entry to 7.0 (CI = 3.3 to 10.9) by wk 14 (P = 0.001). Mean prednisolone dose (mg/d) in study II decreased from 23.8 (CI = 15.0 to 32.5) at entry to 8.8 (CI = 5.9 to 11.7) at wk 14 (P = 0.002). There were two deaths and seven serious infections. Relapse occurred in five patients (three in study II) after a mean of 27 wk. CONCLUSION: TNFalpha blockade with infliximab was effective at inducing remission in 88% of patients with antibody-associated systemic vasculitis and permitted reduction in steroid doses. Severe infections were seen in 21% of patients, and despite continued infliximab, 20% of initial responders experienced disease flares. Infliximab is a promising new therapy for vasculitis both as a component of initial therapy and in the management of refractory disease. These results need confirmation in larger randomized trials.


Assuntos
Anticorpos Anticitoplasma de Neutrófilos/sangue , Anticorpos Monoclonais/farmacologia , Anticorpos Monoclonais/uso terapêutico , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Vasculite Leucocitoclástica Cutânea/sangue , Vasculite Leucocitoclástica Cutânea/tratamento farmacológico , Adulto , Feminino , Granulomatose com Poliangiite/sangue , Granulomatose com Poliangiite/complicações , Humanos , Infliximab , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Vasculite Leucocitoclástica Cutânea/complicações
10.
J Rheumatol ; 30(7): 1621-3, 2003 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12858468

RESUMO

The diagnosis of gut vasculitis infers a poor prognosis necessitating aggressive therapy. We describe a case with predominant features of a skin-limited vasculitis but atypical debilitating abdominal symptoms. Although endoscopic biopsies were unremarkable, full thickness biopsy taken at laparotomy revealed a necrotizing vasculitis. After treatment with cyclophosphamide, the previously resistant abdominal symptoms resolved. This case illustrates the need to tailor treatment to disease severity, rather than determine it by the type of vasculitis with which the patient has been labelled. In view of the importance of gastrointestinal involvement to therapy decisions, laparotomy may be necessary to establish the presence of vasculitis.


Assuntos
Laparotomia , Púrpura/diagnóstico , Vasculite Leucocitoclástica Cutânea/diagnóstico , Ciclofosfamida/uso terapêutico , Quimioterapia Combinada , Feminino , Humanos , Imunossupressores/uso terapêutico , Metilprednisolona/uso terapêutico , Pessoa de Meia-Idade , Necrose , Púrpura/tratamento farmacológico , Púrpura/etiologia , Tomografia Computadorizada por Raios X , Resultado do Tratamento , Vasculite Leucocitoclástica Cutânea/complicações , Vasculite Leucocitoclástica Cutânea/tratamento farmacológico
11.
N Engl J Med ; 349(1): 36-44, 2003 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-12840090

RESUMO

BACKGROUND: The primary systemic vasculitides usually associated with autoantibodies to neutrophil cytoplasmic antigens include Wegener's granulomatosis and microscopic polyangiitis. We investigated whether exposure to cyclophosphamide in patients with generalized vasculitis could be reduced by substitution of azathioprine at remission. METHODS: We studied patients with a new diagnosis of generalized vasculitis and a serum creatinine concentration of 5.7 mg per deciliter (500 micromol per liter) or less. All patients received at least three months of therapy with oral cyclophosphamide and prednisolone. After remission, patients were randomly assigned to continued cyclophosphamide therapy (1.5 mg per kilogram of body weight per day) or a substitute regimen of azathioprine (2 mg per kilogram per day). Both groups continued to receive prednisolone and were followed for 18 months from study entry. Relapse was the primary end point. RESULTS: Of 155 patients studied, 144 (93 percent) entered remission and were randomly assigned to azathioprine (71 patients) or continued cyclophosphamide (73 patients). There were eight deaths (5 percent), seven of them during the first three months. Eleven relapses occurred in the azathioprine group (15.5 percent), and 10 occurred in the cyclophosphamide group (13.7 percent, P=0.65). Severe adverse events occurred in 15 patients during the induction phase (10 percent), in 8 patients in the azathioprine group during the remission phase (11 percent), and in 7 patients in the cyclophosphamide group during the remission phase (10 percent, P=0.94 for the comparison between groups during the remission phase). The relapse rate was lower among the patients with microscopic polyangiitis than among those with Wegener's granulomatosis (P=0.03). CONCLUSIONS: In patients with generalized vasculitis, the withdrawal of cyclophosphamide and the substitution of azathioprine after remission did not increase the rate of relapse. Thus, the duration of exposure to cyclophosphamide may be safely reduced.


Assuntos
Anticorpos Anticitoplasma de Neutrófilos/sangue , Azatioprina/uso terapêutico , Ciclofosfamida/uso terapêutico , Imunossupressores/uso terapêutico , Vasculite/tratamento farmacológico , Adulto , Idoso , Azatioprina/efeitos adversos , Ciclofosfamida/efeitos adversos , Quimioterapia Combinada , Feminino , Glucocorticoides/uso terapêutico , Humanos , Imunossupressores/efeitos adversos , Masculino , Pessoa de Meia-Idade , Neutropenia/induzido quimicamente , Prednisolona/uso terapêutico , Recidiva , Indução de Remissão , Vasculite/imunologia , Vasculite/mortalidade
12.
Rev. chil. reumatol ; 17(3): 133-136, 2001.
Artigo em Inglês | LILACS | ID: lil-317531

RESUMO

The progress in many aspects of vasculitis has emphasised the need for detailed assessment to dissect the components of each individual case as it progresses and to use this to determine progressive therapeutic regimes tailored to the current disease status. Assessment of the extent of organ involvement and the degree of disease activity have obvious value in determining the need for initial therapy at disease presentation. The control of acute mortality has revealed a persistent morbidity, most clearly documented in patient self-assessment of their functional status. The high tendency to relapse also stresses the need for continuing assessment during long-term follow-up. Newer drugs may allow specific control of ongoing activity to be achieved at lower risk of toxicity. The problem of accumulating disease scars has not yet been solved although the detailed description of organ damage has revealed the important contribution which damage makes to later mortality. Finally, there are new techniques to look at the function of the endothelium itself the important target tissue in vasculitis. These will hopefully provide opportunities to assess non invasively the state of blood vessels and their potential to respond to further therapy


Assuntos
Humanos , Vasculite , Endotélio
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