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2.
Br J Ophthalmol ; 94(6): 748-52, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20508050

RESUMO

BACKGROUND/AIMS: Chronic natural killer lymphocytosis (CNKL) has been associated with systemic autoimmunity; however, its association with scleritis or ocular autoimmunity has not been characterised. The natural killer (NK) cell function and immunophenotype of a patient with CNKL who developed bilateral scleritis and multiple systemic autoimmune findings were evaluated. METHODS: The ophthalmic records of a patient with CNKL and scleritis were reviewed over a 6-year period. Flow cytometry was performed to evaluate T cell, NK and B cell populations. NK cellular functions (ie, NK cytotoxicity and cytokine/chemokine production following interleukin 2 (IL2) stimulation) were evaluated. RESULTS: A 56-year-old woman with vitiligo, psoriatic arthritis, thyroiditis, erythema nodosum, bilateral anterior scleritis and Sjogren syndrome was managed with multiple immunosuppressive medications, including prednisone, mycophenolate mofetil and methotrexate. Flow cytometry showed a persistent elevation of CD56(+)CD3(-) NK cells greater than 40%, which was consistent with CNKL. NK cell cytotoxicity assay identified a deficiency of K562 cell lysis in the patient (1.46 mean-fold greater in control vs patient). NK cytokine/chemokine production following IL2 stimulation was also deficient (2.5-32.5-fold greater in control). Cytokines/chemokines assessed included pro-inflammatory (interferon gamma, tumor necrosis factor alpha, IL1, monocyte chemotactic protein 1) and immunoregulatory cytokines (IL4, IL5 and IL10). An abnormal elevation of TCRalpha/beta(+) CD3(+)CD4(-)CD8(-) T cells suggestive of autoimmune lymphoproliferative syndrome was observed; however, apoptosis dysfunction was not found. CONCLUSION: The association of increased but dysfunctional NK cells in the context of multiple systemic and ocular manifestations suggests a role of NK cells in the pathogenesis of our patient's disease. Further studies regarding NK cell dysfunction and ocular autoimmunity are needed.


Assuntos
Doenças Autoimunes/imunologia , Células Matadoras Naturais/imunologia , Linfocitose/imunologia , Esclerite/imunologia , Subpopulações de Linfócitos T/imunologia , Doença Crônica , Citocinas/biossíntese , Citocinas/sangue , Citotoxicidade Imunológica/imunologia , Feminino , Seguimentos , Humanos , Imunofenotipagem , Interleucina-2/imunologia , Pessoa de Meia-Idade , Receptores de Antígenos de Linfócitos T alfa-beta/análise
4.
Clin Exp Immunol ; 140(2): 368-75, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15807864

RESUMO

We report for the first time a significant increased lymphoproliferative response to alpha tropomyosin as well as observing autoantibodies to tropomyosin observed in Behcet's disease (BD) patients with posterior uveitis. Peripheral blood mononuclear cells (PBMCs) from 18 BD patients with posterior uveitis, 18 patients with other forms of noninfectious uveitis, 9 patients with retinal damage due to photocoagulation as well as 18 healthy donors were evaluated for antigen-specific lymphoproliferative responses to alpha tropomyosin and its derivative peptides. The proliferative responses of PBMCs to these antigens were studied using (3)H thymidine incorporation assay. Serum samples were also screened by ELISA for autoantibodies against tropomyosin. Six of the 18 (33%) BD patients with posterior uveitis showed increased proliferative response to alpha tropomyosin or its derivative peptides, while none of the healthy, disease controls were positive. The mean lymphoproliferative responses to tropomyosin were significantly higher (P < 0.02) in the BD patients compared to healthy or disease controls. Higher titres of anti-tropomyosin antibodies were also seen in four of the 18 BD patients but none in the healthy or disease control groups (P < 0.002). The occurrence of these abnormalities supports a possible role for alpha tropomyosin as a self-antigen in a subset of patients with Behcet's disease.


Assuntos
Autoantígenos/imunologia , Síndrome de Behçet/imunologia , Tropomiosina/imunologia , Adolescente , Adulto , Idoso , Autoanticorpos/sangue , Doenças Autoimunes/imunologia , Proliferação de Células , Células Cultivadas , Ensaio de Imunoadsorção Enzimática/métodos , Feminino , Humanos , Ativação Linfocitária/imunologia , Masculino , Pessoa de Meia-Idade , Uveíte Posterior/imunologia
5.
Invest Ophthalmol Vis Sci ; 42(13): 3233-8, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11726628

RESUMO

PURPOSE: Soluble antigen (S-Ag) is a member of the arrestin family of protein with which it shares a high level of homology. It is an immunologically privileged retinal antigen that can elicit experimental autoimmune uveitis (EAU) and is thought to be a target for ocular inflammatory diseases. This study was conducted to identify in humans, the immunogenic determinants of human S-Ag and to establish whether a specific response profile occurs in particular ocular inflammatory conditions. METHODS: Peripheral blood lymphocyte responses were measured against a panel of 40 overlapping synthetic peptides of human S-Ag in patients with chronic uveitis and compared with control subjects. Patients with Behçet disease, sarcoidosis, Vogt-Koyanagi-Harada, and sympathetic ophthalmia were tested. RESULTS: A limited number of immunodominant determinants were identified for Behçet disease and sarcoidosis. These were all located at sites of limited homology with other known arrestins. In addition, several individual patients had prominent proliferative responses to multiple determinants well above that of control subjects. This determinant spread was observed in all disease entities except sympathetic ophthalmia, which did not show any immunoreactivity to S-Ag. Significant response shifts were also noted over time in two patients. CONCLUSIONS: The results indicate that there are specific immunodominant determinants to human S-Ag in patients with certain forms of uveitis. However, in individual patients, response is not limited to these determinants. In the chronic stage of disease, response is spread over many determinants.


Assuntos
Arrestina/imunologia , Epitopos , Uveíte/imunologia , Adulto , Síndrome de Behçet/imunologia , Limiar Diferencial , Feminino , Humanos , Tolerância Imunológica , Ativação Linfocitária/imunologia , Masculino , Pessoa de Meia-Idade , Oftalmia Simpática/imunologia , Valores de Referência , Sarcoidose/imunologia , Síndrome Uveomeningoencefálica/imunologia
6.
Am J Ophthalmol ; 132(5): 794-6, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11704050

RESUMO

PURPOSE: To determine the association between cystoid macular edema and vascular endothelial growth factor concentration in the aqueous humor and plasma of uveitis patients. METHODS: Cross-sectional study. Vascular endothelial growth factor concentrations were measured by enzyme-linked immunosorbent assay in the aqueous humor of 20 uveitis patients (9 with and 11 without cystoid macular edema), and in the plasma of 40 uveitis patients (20 with and 20 without cystoid macular edema) and 20 healthy volunteers. RESULTS: Mean aqueous humor vascular endothelial growth factor concentrations for uveitis patients with and without cystoid macular edema were 152.3 and 109.5 pg/ml, respectively, P =.044. Mean plasma vascular endothelial growth factor concentrations in uveitis patients with and without cystoid macular edema and in healthy volunteers were 32.2, 29.6, and 55.0 pg/ml, respectively. Uveitis patients had lower plasma vascular endothelial growth factor levels than did healthy volunteers, P =.0002. CONCLUSION: In uveitis patients, vascular endothelial growth factor concentration is increased in the aqueous humor of eyes with cystoid macular edema. It may be useful to investigate vascular endothelial growth factor antagonists as a treatment for uveitis-associated cystoid macular edema.


Assuntos
Humor Aquoso/metabolismo , Fatores de Crescimento Endotelial/metabolismo , Linfocinas/metabolismo , Edema Macular/metabolismo , Uveíte/metabolismo , Adolescente , Adulto , Idoso , Criança , Estudos Transversais , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Edema Macular/etiologia , Masculino , Pessoa de Meia-Idade , Uveíte/complicações , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio Vascular
8.
Arch Ophthalmol ; 119(10): 1518-24, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11594954

RESUMO

OBJECTIVE: To investigate the pharmacokinetics and toxicity of intravitreal chemotherapeutic agents in the rabbit eye for the potential treatment of primary intraocular lymphoma and other intraocular malignancies. METHODS: The ocular pharmacokinetics of intravitreal methotrexate sodium (400 microg) was studied in 10 New Zealand white rabbits, and a single-compartment, first-order elimination model was used to calculate the drug half-life. With the use of these data, a treatment schedule using serial injections of intravitreal methotrexate and single injections of fluorouracil and dexamethasone sodium phosphate was developed. This schedule was studied in 4 New Zealand white rabbits to explore the combined toxicity of these agents. RESULTS: Methotrexate vitreous levels, following a 400-microg intravitreal injection, remained therapeutic (>0.5 microM) in the rabbit eye for 48 to 72 hours. Intravitreal methotrexate, combined with fluorouracil and dexamethasone, showed no evidence of drug toxicity as determined by electroretinography and histopathologic examination. CONCLUSIONS: A treatment schedule for primary intraocular lymphoma consisting of methotrexate intravitreal injections every 48 to 72 hours provides therapeutic drug concentrations in the vitreous and, in combination with fluorouracil and dexamethasone, appears to be safe in the rabbit eye. CLINICAL RELEVANCE: Although responsive to conventional chemotherapy or radiotherapy, recurrence of ocular involvement with primary central nervous system lymphoma occurs in more than 50% of treated cases. Anecdotal reports of the use of intravitreal chemotherapy for primary intraocular lymphoma have been encouraging. However, animal data on the pharmacokinetics and toxicity of combined intravitreal agents for the treatment of this disease are lacking.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacocinética , Protocolos de Quimioterapia Combinada Antineoplásica/toxicidade , Neoplasias Oculares/tratamento farmacológico , Linfoma/tratamento farmacológico , Corpo Vítreo/metabolismo , Animais , Disponibilidade Biológica , Cromatografia Líquida de Alta Pressão , Dexametasona/administração & dosagem , Eletrorretinografia/efeitos dos fármacos , Feminino , Fluoruracila/administração & dosagem , Meia-Vida , Masculino , Metotrexato/administração & dosagem , Coelhos , Retina/efeitos dos fármacos , Retina/patologia
9.
Ocul Immunol Inflamm ; 9(2): 75-84, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11449323

RESUMO

PURPOSE: Gyrate atrophy (GA) is a rare hereditary disease that causes retinal destruction. Retinal damage in GA and other heredodegenerative diseases such as retinitis pigmentosa (RP) releases sequestered antigens and may trigger immune response to these molecules. Here, we studied the immune response to retinal antigens in patients with GA and RP and compared it with that of patients with inactive posterior uveitis and normal volunteers. PATIENTS AND METHODS: Peripheral blood was collected from 24 patients with RP, 10 patients with GA, 10 patients with inactive posterior uveitis, and 16 normal volunteers. Cell-mediated immune responses to human S-antigen (HS-Ag), bovine S-antigen (BS-Ag), and interphotoreceptor retinoid-binding protein (IRBP) were investigated by lymphocyte proliferation assay. In addition, serum levels of soluble intercellular adhesion molecule-1 (sICAM-1) and soluble vascular cell adhesion molecule-1 (sVCAM-1) were studied by ELISA. Immunologic data were correlated with clinical and electrophysiological findings. RESULTS: Patients with GA or RP responded to HS-Ag and BS-Ag more vigorously than patients with uveitis or healthy controls, as shown by higher mean stimulation indices and larger proportions of responders. Unlike S-Ag, IRBP stimulated low lymphocyte responses in only a small proportion of RP patients. The mean sVCAM-1 levels were significantly higher in the sera from patients with GA than in that from normal controls. CONCLUSION: An elevated cellular immune response to S-Ag is common in patients with GA and RP. This elevated cellular immune response to S-Ag may exacerbate retinal destruction in patients with GA and RP.


Assuntos
Arrestina/imunologia , Proteínas do Olho , Atrofia Girata/imunologia , Retina/imunologia , Retinose Pigmentar/imunologia , Proteínas de Ligação ao Retinol/imunologia , Uveíte Posterior/imunologia , Adolescente , Adulto , Idoso , Autoantígenos/imunologia , Criança , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Imunidade Celular , Molécula 1 de Adesão Intercelular/sangue , Ativação Linfocitária/imunologia , Masculino , Pessoa de Meia-Idade , Molécula 1 de Adesão de Célula Vascular/sangue
12.
Arch Ophthalmol ; 119(5): 667-9, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11346393

RESUMO

OBJECTIVE: To assess the course of change of visual function outcome variables in 5 patients with gyrate atrophy before a gene replacement therapy clinical trial. METHODS: The outcome variables selected were visual field sensitivity and electroretinogram amplitude. The course of change of these outcome variables was determined by calculation of their half-lives. RESULTS: In the 4 to 6 years during which each patient was followed up for this study, median visual field half-lives were 17.0 years (static perimetry) and 11.4 years (kinetic perimetry). Median electroretinogram half-lives were 16.0 years (maximal response) and 10.7 years (flicker response). CONCLUSIONS: The course of the decline of visual function outcome variables is frequently slow. Thus, a long-term clinical trial would be required to assess the efficacy of the intervention in the preservation of visual function.


Assuntos
Terapia Genética , Atrofia Girata/fisiopatologia , Retina/fisiopatologia , Acuidade Visual/fisiologia , Campos Visuais/fisiologia , Adulto , Idoso , Eletrorretinografia , Atrofia Girata/terapia , Humanos , Pessoa de Meia-Idade , Testes de Campo Visual
13.
Curr Opin Oncol ; 13(3): 137-42, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11307054

RESUMO

Primary intraocular lymphoma (PIOL) is a variant of primary central nervous system lymphoma in which lymphoma cells are initially present only in the eyes without evidence of disease in the brain or cerebrospinal fluid. Patients with PIOL are typically older adults who present with blurred vision and floaters. The ophthalmic examination characteristically shows a cellular infiltrate in the vitreous with or without the presence of subretinal infiltrates. Diagnostic evaluation for PIOL includes neuroimaging, cytologic examination of the cerebrospinal fluid, and a diagnostic vitrectomy with special handling of the vitreous specimen, if the former is nondiagnostic. Molecular and cytokine analyses are useful adjuncts to cytology for the diagnosis of PIOL. Recent molecular studies demonstrating viral DNA in the ocular lymphoma cells suggest a role for infectious agents in the pathogenesis of PIOL. To date, the best mode for treatment of PIOL or recurrent primary central nervous system lymphoma involving only the eyes remains undefined.


Assuntos
Neoplasias do Sistema Nervoso Central/diagnóstico , Neoplasias Oculares/diagnóstico , Linfoma/diagnóstico , Neoplasias da Retina/diagnóstico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias do Sistema Nervoso Central/epidemiologia , Angiofluoresceinografia/métodos , Fundo de Olho , Humanos , Pessoa de Meia-Idade
14.
Am J Ophthalmol ; 131(3): 351-4, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11239868

RESUMO

PURPOSE: To understand better the natural history of ocular toxoplasmosis by reexamining a well-characterized population in Southern Brazil. METHODS: Ophthalmological examination and serologic tests for Toxoplasma gondii infection were performed in 1997 on 383 individuals who had undergone the same evaluation in 1990. RESULTS: Of 109 seronegative subjects in 1990, 21 (19.3%) became seropositive by 1997, and 2 (1.5% of previously seronegative patients; 9.5% of those known to have seroconverted) developed ocular toxoplasmosis. Seroconversion occurred more frequently in individuals under 17 years of age (16 of 46 patients, 34.8%) than in those greater than 17 years of age (5 of 63 patients, 7.9%; p = 0.002). Of 131 seropositive individuals who did not have ocular lesions in 1990, 11 (8.3%) had typical toxoplasmic lesions in 1997. Of the 13 individuals with non-specific hyperpigmented small retinal lesions in 1990, 3 (23%) presented with typical lesions in 1997. CONCLUSIONS: Acquired T. gondii infection can result in late development of ocular lesions. Small, non-specific hyperpigmented retinal lesions may represent sites of T. gondii infection in seropositive individuals.


Assuntos
Doenças Retinianas/epidemiologia , Toxoplasma/imunologia , Toxoplasmose Ocular/epidemiologia , Adolescente , Adulto , Animais , Anticorpos Antiprotozoários/sangue , Brasil/epidemiologia , Criança , Feminino , Seguimentos , Fundo de Olho , Humanos , Incidência , Masculino , Retina/patologia , Doenças Retinianas/diagnóstico , Doenças Retinianas/parasitologia , Estudos Soroepidemiológicos , Toxoplasmose Ocular/diagnóstico , Toxoplasmose Ocular/parasitologia
15.
Am J Ophthalmol ; 131(3): 394-6, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11239884

RESUMO

PURPOSE: In adults with human immunodeficiency virus (HIV) infection, frosted branch angiitis is commonly associated with cytomegalovirus retinitis and responds to anti-cytomegalovirus therapy. We describe the first pediatric case of HIV-associated frosted branch angiitis. METHODS: Case report. RESULTS: A 7-year-old HIV-infected male with frosted branch angiitis was refractory to induction doses of intravenous ganciclovir and foscarnet over a 2-month period. Although cytomegalovirus antigenemia resolved, the angiitis only improved after subsequent treatment with systemic corticosteroids. CONCLUSION: Frosted branch angiitis in this patient was not attributed to cytomegalovirus. The pathogenesis of HIV-associated frosted branch angiitis may differ between children and adults.


Assuntos
Infecções por HIV/complicações , Doenças Retinianas/etiologia , Vasos Retinianos/patologia , Vasculite/etiologia , Antivirais/uso terapêutico , Criança , Retinite por Citomegalovirus/complicações , Retinite por Citomegalovirus/diagnóstico , Retinite por Citomegalovirus/tratamento farmacológico , Foscarnet/uso terapêutico , Ganciclovir/uso terapêutico , Glucocorticoides/uso terapêutico , Infecções por HIV/diagnóstico , Infecções por HIV/tratamento farmacológico , Humanos , Masculino , Doenças Retinianas/diagnóstico , Doenças Retinianas/tratamento farmacológico , Vasos Retinianos/efeitos dos fármacos , Vasculite/diagnóstico , Vasculite/tratamento farmacológico
16.
Am J Ophthalmol ; 130(4): 492-513, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11024423

RESUMO

PURPOSE: To provide recommendations for the use of immunosuppressive drugs in the treatment of patients with ocular inflammatory disorders. PARTICIPANTS: A 12-person panel of physicians with expertise in ophthalmologic, pediatric, and rheumatologic disease, in research, and in the use of immunosuppressive drugs in patient care. EVIDENCE: Published clinical study results. Recommendations were rated according to the quality and strength of available evidence. PROCESS: The panel was convened in September of 1999 and met regularly through May 2000. Subgroups of the panel summarized and presented available information on specific topics to the full panel; recommendations and ratings were determined by group consensus. CONCLUSIONS: Although corticosteroids represent one of the mainstays in the management of patients with ocular inflammation, in many patients, the severity of the disease, the presence of corticosteroid side effects, or the requirement for doses of systemic corticosteroids highly likely to result in corticosteroid complications supports the rationale for immunosuppressive drugs (for example, antimetabolites, T-cell inhibitors, and alkylating agents) being used in the management of these patients. Because of the potential for side effects, treatment must be individualized and regular monitoring performed. With careful use of immunosuppressive drugs for treatment of ocular inflammatory disorders, many patients will benefit from them either with better control of the ocular inflammation or with a decrease in corticosteroid side effects.


Assuntos
Endoftalmite/tratamento farmacológico , Imunossupressores/uso terapêutico , Quimioterapia Combinada , Humanos , Imunossupressores/efeitos adversos , Guias de Prática Clínica como Assunto
17.
Surv Ophthalmol ; 44(6): 518-26, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10906383

RESUMO

Non-Hodgkin's lymphoma involves ocular tissues either as a primary tumor or as secondary metastasis from systemic disease. Diagnosis is based on the identification of malignant cells in the eye by biopsy. Although primary intraocular lymphoma cells have been identified in the optic nerve, ciliary body, and iris of a small number of patients by histopathology, these sites of infiltration have rarely been observed on clinical examination. We studied clinical and histopathological findings of two patients with iris infiltration by primary intraocular lymphoma and reviewed the findings of 163 cases reported in the literature.


Assuntos
Neoplasias da Íris/patologia , Linfoma de Células B/patologia , Linfoma Difuso de Grandes Células B/patologia , Biópsia , Terapia Combinada , Diagnóstico Diferencial , Feminino , Humanos , Neoplasias da Íris/terapia , Linfoma de Células B/terapia , Linfoma Difuso de Grandes Células B/terapia , Masculino , Pessoa de Meia-Idade , Acuidade Visual , Corpo Vítreo/patologia
18.
J Infect Dis ; 181(6): 2018-22, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10837184

RESUMO

Many persons infected with Toxoplasma gondii develop ocular lesions. Immunologic parameters in the response to T. gondii were evaluated in infected persons with and without ocular lesions and in noninfected controls. Subjects were divided into groups on the basis of presence of serum antibodies to T. gondii, presence of ocular lesions, and clinical history. Production of interleukin-2 and interferon-gamma by peripheral blood mononuclear cells from patients with probable congenital toxoplasmosis was decreased, compared with that in persons with presumed acquired infection. Cell proliferation and delayed-type skin reaction induced by soluble toxoplasma tachyzoite antigen followed the same pattern. Asymptomatic persons showed high levels of interleukin-12 and interferon-gamma, whereas persons with ocular lesions had high interleukin-1 and tumor necrosis factor-alpha responses toward soluble toxoplasma tachyzoite antigen. These data suggest that patients with ocular disease due to congenital infection show tolerance toward the parasite. Furthermore, susceptibility to ocular lesions after acquired toxoplasmosis is associated with high levels of interleukin-1 and tumor necrosis factor-alpha, whereas resistance is associated with high levels of interleukin-12 and interferon-gamma.


Assuntos
Antígenos de Protozoários/imunologia , Toxoplasmose Congênita/imunologia , Toxoplasmose/imunologia , Adolescente , Adulto , Citocinas/biossíntese , Feminino , Humanos , Ativação Linfocitária , Masculino , Pessoa de Meia-Idade , Receptores de Antígenos de Linfócitos T alfa-beta/análise
20.
J Clin Oncol ; 18(4): 927-41, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10673536

RESUMO

PURPOSE: To determine the maximum-tolerated dose, toxicities, and pharmacokinetic profile of the farnesyl protein transferase inhibitor R115777 when administered orally bid for 5 days every 2 weeks. PATIENTS AND METHODS: Twenty-seven patients with a median age of 58 years received 85 cycles of R115777 using an intrapatient and interpatient dose escalation schema. Drug was administered orally at escalating doses as a solution (25 to 850 mg bid) or as pellet capsules (500 to 1300 mg bid). Pharmacokinetics were assessed after the first dose and the last dose administered during cycle 1. RESULTS: Dose-limiting toxicity of grade 3 neuropathy was observed in one patient and grade 2 fatigue (decrease in two performance status levels) was seen in four of six patients treated with 1,300 mg bid. The most frequent clinical grade 2 or 3 adverse events in any cycle included nausea, vomiting, headache, fatigue, anemia, and hypotension. Myelosuppression was mild and infrequent. Peak plasma concentrations of R115777 were achieved within 0.5 to 4 hours after oral drug administration. The elimination of R115777 from plasma was biphasic, with sequential half-lives of about 5 hours and 16 hours. There was little drug accumulation after bid dosing, and steady-state concentrations were achieved within 2 to 3 days. The pharmacokinetics were dose proportional in the 25 to 325 mg/dose range for the oral solution. Urinary excretion of unchanged R115777 was less than 0.1% of the oral dose. One patient with metastatic colon cancer treated at the 500-mg bid dose had a 46% decrease in carcinoembryonic antigen levels, improvement in cough, and radiographically stable disease for 5 months. CONCLUSION: R115777 is bioavailable after oral administration and has an acceptable toxicity profile. Based upon pharmacokinetic data, the recommended dose for phase II trials is 500 mg orally bid (total daily dose, 1, 000 mg) for 5 consecutive days followed by 9 days of rest. Studies of continuous dosing and studies of R115777 in combination with chemotherapy are ongoing.


Assuntos
Alquil e Aril Transferases/antagonistas & inibidores , Inibidores Enzimáticos/uso terapêutico , Neoplasias/tratamento farmacológico , Quinolonas/uso terapêutico , Administração Oral , Adulto , Idoso , Anemia/induzido quimicamente , Disponibilidade Biológica , Medula Óssea/efeitos dos fármacos , Cápsulas , Esquema de Medicação , Inibidores Enzimáticos/efeitos adversos , Inibidores Enzimáticos/farmacocinética , Farnesiltranstransferase , Fadiga/induzido quimicamente , Feminino , Meia-Vida , Cefaleia/induzido quimicamente , Humanos , Hipotensão/induzido quimicamente , Masculino , Taxa de Depuração Metabólica , Pessoa de Meia-Idade , Náusea/induzido quimicamente , Doenças do Sistema Nervoso Periférico/induzido quimicamente , Quinolonas/efeitos adversos , Quinolonas/farmacocinética , Soluções , Vômito/induzido quimicamente
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