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1.
Orbit ; 40(4): 287-291, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32567441

RESUMO

PURPOSE: The role of silicone stent intubation in dacryocystorhinostomy (DCR) is not clear, and conclusions presented in the literature are contradictory both regarding if intubation should be recommended and if so, the appropriate duration of intubation. This paper reports on the long-term outcome of a comparatively short duration of silicone stent intubation, one week, and discusses the possibility of an optimal duration of intubation where the benefit of the silicone stent is utilized but with minimal risk of complications. METHODS: A total of 70 cases of DCR were followed in 67 patients for four years in a descriptive case series of uncomplicated external DCR with one-week silicone stent intubation. Pre- and perioperative findings, complications, and the need for additional surgery were recorded. At end of follow-up, a questionnaire was sent to the patients asking them to grade the frequency of epiphoric problems. If graded often/constant, a follow-up visit was offered. RESULTS: One patient received additional surgery during follow-up due to persistent epiphora caused by synechiae between the middle turbinate and lateral nasal wall. The response rate to the questionnaire was 88%, with 93% of the respondents reporting epiphora never/seldom. Four patients reported persistent problems: one declined further examination, the tear duct was anatomically patent in two, and one was referred to the ENT department due to inflamed nasal mucosa and extensive adhesions. The long-term functional or anatomical success rate was 97%. CONCLUSIONS: This study shows that a high long-term success rate for uncomplicated DCR is possible with only one-week silicone stent intubation.


Assuntos
Dacriocistorinostomia , Doenças do Aparelho Lacrimal , Ducto Nasolacrimal , Humanos , Intubação Intratraqueal , Ducto Nasolacrimal/cirurgia , Elastômeros de Silicone
2.
Science ; 356(6342): 1069-1072, 2017 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-28596364

RESUMO

The origin of cometary matter and the potential contribution of comets to inner-planet atmospheres are long-standing problems. During a series of dedicated low-altitude orbits, the Rosetta Orbiter Spectrometer for Ion and Neutral Analysis (ROSINA) on the Rosetta spacecraft analyzed the isotopes of xenon in the coma of comet 67P/Churyumov-Gerasimenko. The xenon isotopic composition shows deficits in heavy xenon isotopes and matches that of a primordial atmospheric component. The present-day Earth atmosphere contains 22 ± 5% cometary xenon, in addition to chondritic (or solar) xenon.

3.
Nature ; 526(7575): 678-81, 2015 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-26511578

RESUMO

The composition of the neutral gas comas of most comets is dominated by H2O, CO and CO2, typically comprising as much as 95 per cent of the total gas density. In addition, cometary comas have been found to contain a rich array of other molecules, including sulfuric compounds and complex hydrocarbons. Molecular oxygen (O2), however, despite its detection on other icy bodies such as the moons of Jupiter and Saturn, has remained undetected in cometary comas. Here we report in situ measurement of O2 in the coma of comet 67P/Churyumov-Gerasimenko, with local abundances ranging from one per cent to ten per cent relative to H2O and with a mean value of 3.80 ± 0.85 per cent. Our observations indicate that the O2/H2O ratio is isotropic in the coma and does not change systematically with heliocentric distance. This suggests that primordial O2 was incorporated into the nucleus during the comet's formation, which is unexpected given the low upper limits from remote sensing observations. Current Solar System formation models do not predict conditions that would allow this to occur.


Assuntos
Meteoroides , Oxigênio/análise , Monóxido de Carbono/análise , Meio Ambiente Extraterreno/química , Gelo/análise , Nitrogênio/análise , Oxigênio/efeitos da radiação , Fotólise , Sistema Solar/química , Astronave , Água/análise
4.
Science ; 348(6231): 232-5, 2015 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-25791084

RESUMO

Molecular nitrogen (N2) is thought to have been the most abundant form of nitrogen in the protosolar nebula. It is the main N-bearing molecule in the atmospheres of Pluto and Triton and probably the main nitrogen reservoir from which the giant planets formed. Yet in comets, often considered the most primitive bodies in the solar system, N2 has not been detected. Here we report the direct in situ measurement of N2 in the Jupiter family comet 67P/Churyumov-Gerasimenko, made by the Rosetta Orbiter Spectrometer for Ion and Neutral Analysis mass spectrometer aboard the Rosetta spacecraft. A N2/CO ratio of (5.70 ± 0.66) × 10(-3) (2σ standard deviation of the sampled mean) corresponds to depletion by a factor of ~25.4 ± 8.9 as compared to the protosolar value. This depletion suggests that cometary grains formed at low-temperature conditions below ~30 kelvin.

5.
Science ; 347(6220): aaa0276, 2015 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-25613892

RESUMO

Comets contain the best-preserved material from the beginning of our planetary system. Their nuclei and comae composition reveal clues about physical and chemical conditions during the early solar system when comets formed. ROSINA (Rosetta Orbiter Spectrometer for Ion and Neutral Analysis) onboard the Rosetta spacecraft has measured the coma composition of comet 67P/Churyumov-Gerasimenko with well-sampled time resolution per rotation. Measurements were made over many comet rotation periods and a wide range of latitudes. These measurements show large fluctuations in composition in a heterogeneous coma that has diurnal and possibly seasonal variations in the major outgassing species: water, carbon monoxide, and carbon dioxide. These results indicate a complex coma-nucleus relationship where seasonal variations may be driven by temperature differences just below the comet surface.

6.
Science ; 347(6220): 1261952, 2015 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-25501976

RESUMO

The provenance of water and organic compounds on Earth and other terrestrial planets has been discussed for a long time without reaching a consensus. One of the best means to distinguish between different scenarios is by determining the deuterium-to-hydrogen (D/H) ratios in the reservoirs for comets and Earth's oceans. Here, we report the direct in situ measurement of the D/H ratio in the Jupiter family comet 67P/Churyumov-Gerasimenko by the ROSINA mass spectrometer aboard the European Space Agency's Rosetta spacecraft, which is found to be (5.3 ± 0.7) × 10(-4)­that is, approximately three times the terrestrial value. Previous cometary measurements and our new finding suggest a wide range of D/H ratios in the water within Jupiter family objects and preclude the idea that this reservoir is solely composed of Earth ocean-like water.

7.
Environ Int ; 64: 61-8, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24368294

RESUMO

Brominated flame retardants (BFRs) are used in a wide variety of products such as electronic devices, upholstery and carpets and in insulation boards. The study presented here aimed to quantify the amounts of BFRs in house dust in Germany. For this purpose 20 residences' dust samples were collected from vacuum cleaner bags and analysed with LC-MS/MS and simultaneously with GC/MS. Using GC/MS, the median (95th percentile) concentrations of PBDEs (sum of tetra- to hepta-congeners), BDE 209, Σ-HBCD (sum of three congeners), and decabromodiphenylethane (DBDPE) were 42ng/g (230ng/g), 950ng/g (3426ng/g), 335ng/g (1545ng/g), and 146ng/g (1059ng/g), respectively. Using LC-MS/MS some "novel" flame retardants were found in median concentrations of 343ng/g (bis(2-ethyl-1-hexyl)tetrabromophthalate, TBPH), and 28ng/g (tetrabromobisphenol A, TBBPA). Whilst 1,2-bis-(2,4,6-tribromophenoxy)ethane (BTBPE) and 2-ethyl-1-hexyl-2,3,4,5-tetrabromobenzoate (EH-TBB) could not be detected. Based on these measurements an exposure assessment for the sum of tetra- to heptabrominated congeners, BDE 209, and Σ-HBCD resulted in a "high" daily intake for toddlers (based on 95th percentiles) of 1.2ng/kg b.w., 0.69ng/kg b.w., and 8.9ng/kg b.w., respectively. For TBPH the "high" intake was calculated at 4.1ng/kg b.w. and for DBDPE at 5.3ng/kg b.w. A clear tendency was observed to apply "novel" BFRs in Germany. Moreover, the results suggest that the recent exposure to PBDEs and HBCD via house dust in Germany is well below the levels that are associated with health effects. For the "novel" brominated flame retardants such an assessment is not possible due to limited toxicological information.


Assuntos
Poeira/análise , Monitoramento Ambiental , Retardadores de Chama/análise , Éteres Difenil Halogenados/análise , Cromatografia Gasosa-Espectrometria de Massas , Alemanha , Humanos , Hidrocarbonetos Bromados/análise , Bifenil Polibromatos/análise , Espectrometria de Massas em Tandem
8.
J Chromatogr A ; 1241: 28-36, 2012 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-22546182

RESUMO

Brominated flame retardants (BFRs) are persistent and widespread chemicals. Therefore human beings are exposed to BFRs. House dust may be one source of exposure and contains a lot of xenobiotics in relatively high concentrations. In contrast to common GC-MS based methods here an online LC-MS/MS method is presented to quantify 16 BFRs in dust using ultrasonic solvent extraction as a single sample work up step. LOQ from 0.6 (tetrabromobisphenol A) to 80 (polybrominated diphenylethers (BDE 28) ng/g dust were achieved. Data for accuracy, precision and recovery are presented and are comparable to common LC-MS/MS methods in different matrices. In addition 5 real house dust samples were analyzed with high concentration (535 ng/g) for bis(2-ethyl-1-hexyl)tetrabromophthalate which is a novel alternative BFRs to replace common BDE's.


Assuntos
Poluição do Ar em Ambientes Fechados/análise , Fracionamento Químico/métodos , Poeira/análise , Retardadores de Chama/análise , Éteres Difenil Halogenados/análise , Bifenil Polibromatos/análise , Cromatografia Líquida/métodos , Retardadores de Chama/isolamento & purificação , Éteres Difenil Halogenados/isolamento & purificação , Limite de Detecção , Modelos Lineares , Bifenil Polibromatos/isolamento & purificação , Reprodutibilidade dos Testes , Sonicação , Espectrometria de Massas em Tandem/métodos
10.
Br J Ophthalmol ; 88(11): 1422-4, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15489486

RESUMO

AIM: To report symptoms and findings of lacrimal duct malfunction after topical mitomycin C (MMC) for conjunctival neoplasia. METHODS: 14 consecutive patients treated with 1-6 cycles of topical 0.04% MMC four times daily for periods of 2 weeks were interviewed about symptoms of lacrimal duct malfunction. Patients who complained of tearing had examination of the puncta and canaliculi including probing and lacrimal duct irrigation. RESULTS: Nine patients complained of epiphora after topical MMC. Three of these patients had normal puncta and canaliculi, patent to irrigation. In these patients epiphora ceased spontaneously after probing and irrigation. The additional six patients had stenosis of the punctum (n = 3), the common canaliculus (n = 1), both puncta and both canaliculi (n = 1) and complete occlusion of the lower canaliculus (n = 1). CONCLUSION: Obstruction of the puncta or canaliculi is not an infrequent event after topical 0.04% MMC.


Assuntos
Antibióticos Antineoplásicos/efeitos adversos , Neoplasias da Túnica Conjuntiva/tratamento farmacológico , Obstrução dos Ductos Lacrimais/induzido quimicamente , Mitomicina/efeitos adversos , Lágrimas/metabolismo , Administração Tópica , Adulto , Idoso , Idoso de 80 Anos ou mais , Antibióticos Antineoplásicos/administração & dosagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mitomicina/administração & dosagem , Estudos Retrospectivos
11.
Br J Ophthalmol ; 88(7): 911-4, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15205236

RESUMO

AIM: Evaluation of the benefits of a new technique for pterygium surgery with respect to postoperative pain and surgery time. METHODS: A prospective randomised clinical trial was carried out in 43 patients. 43 eyes were operated for primary nasal pterygium. Autologous conjunctival graft taken at the superotemporal limbus was used to cover the sclera after pterygium excision. After randomisation, in 20 patients the transplant was attached to the sclera with a fibrin tissue adhesive (Tisseel Duo Quick) and in 23 patients with absorbable sutures (7-0 Vicryl Rapid). The Mann-Whitney test was used as statistical analysis. Postoperative pain was graded according to the visual analogue scale (VAS) twice daily during the first week after surgery. Surgery time was noted from the first incision until the lid speculum was removed. RESULTS: The average pain was significantly lower when glue had been used, p<0.05. Average surgery time was 9.7 minutes (range 6-13) for glue and 18.5 minutes (range 12-30) for sutures, p<0.001. No complications occurred. CONCLUSION: Using glue instead of sutures when attaching the conjunctival transplant in pterygium surgery causes significantly less postoperative pain and shortens surgery time significantly.


Assuntos
Pterígio/cirurgia , Adulto , Idoso , Túnica Conjuntiva/transplante , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Oftalmológicos/métodos , Dor Pós-Operatória/etiologia , Complicações Pós-Operatórias/etiologia , Período Pós-Operatório , Estudos Prospectivos , Suturas , Fatores de Tempo , Adesivos Teciduais , Transplante Autólogo
12.
Graefes Arch Clin Exp Ophthalmol ; 238(8): 682-9, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11011689

RESUMO

BACKGROUND: In some retinal diseases and following transplantation of retinal pigment epithelium (RPE), melanin granules are liberated to the subretinal space. Our aim was to investigate the cellular response to implanted extracellular melanin. METHODS: After pars plana vitrectomy, 17 albino rabbits received a suspension of melanin granules in the subretinal space. Postoperative examination included ophthalmoscopy, color fundus photography, histology using monoclonal antibodies identifying RPE cells (AE1/3), macrophages (RAM 11), B-lymphocytes (CD20) and T-lymphocytes (CD45), and electron microscopy. The follow-up time was 2 weeks, 4 weeks and 6 months. RESULTS: On fundus photographs, the layer of melanin showed focal attenuation with lighter areas at 6 months. Melanin granules were phagocytosed by RPE cells and macrophages at 2 weeks, as identified by monoclonal antibodies. In areas where an abundance of melanin was present, multilayers of macrophages were seen associated with considerable photoreceptor damage. Pigment-laden cells invaded the neural retina. The cellular infiltration of the retina was focal, and when it involved the outer nuclear layer the photoreceptor damage was severe. Electron microscopy demonstrated the presence of melanosomes intracellularly in Müller glia. The process of phagocytosis and removal of melanin granules from the subretinal space was slow and not completed at 6 months. CONCLUSION: Our experiments show that implantation of melanin granules in the subretinal space of albino rabbits may induce a considerable phagocytic cellular response featuring the host's RPE, macrophages and glial cells. The migration of pigment-laden cells into the neural retina was associated with focal photoreceptor damage.


Assuntos
Movimento Celular/fisiologia , Melaninas/administração & dosagem , Células Fotorreceptoras de Vertebrados/ultraestrutura , Epitélio Pigmentado Ocular/ultraestrutura , Animais , Linfócitos B/ultraestrutura , Implantes de Medicamento , Macrófagos/ultraestrutura , Fagocitose/fisiologia , Coelhos , Linfócitos T/ultraestrutura
13.
Acta Ophthalmol Scand ; 78(2): 122-9, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10794242

RESUMO

PURPOSE: To determine the effects of systemic cyclosporine A (CsA) on the survival of retinal pigment epithelial (RPE) allografts in the subretinal space in an animal model using atraumatic transplantation surgery. METHODS: Following pars plana vitrectomy, an RPE cell suspension from brown rabbits was injected with a glass micropipette into the subretinal space of 39 albino rabbits. For immunosuppression, 22 rabbits were given an injection of CsA, 20 mg daily intramuscularly, 17 rabbits with RPE grafts were controls. The grafts were monitored by biomicroscopy, color fundus photography, and fluorescein angiography. Rabbits were sacrificed at 1, 3 and 6 months, respectively, and the eyes processed for light and electron microscopy including immunohistochemistry. RESULTS: After three months, the transplanted RPE cells, in both the CsA group and the controls, formed a monolayer in the subretinal space. Although a few macrophages were encountered, there was no massive cellular infiltration and the photoreceptor layer was well preserved. After six months, however, there was a disruption of grafted RPE cells in both groups, characterized by dispersion of melanin pigment in the subretinal space, and invasion of macrophages with focal photoreceptor damage but no infiltration of lymphocytes in the retina or choroid. No significant differences between the CsA treated and the control eyes were discernible. CONCLUSION: Although the subretinal space has been considered an immunologically privileged site, we found that the survival of RPE allografts was limited. CsA did not prevent RPE allograft destruction in the subretinal space. The transplant seems to be disrupted either by immunological mechanisms that are not inhibited by CsA, or by nonimmunologic events.


Assuntos
Transplante de Células , Ciclosporina/uso terapêutico , Sobrevivência de Enxerto/efeitos dos fármacos , Imunossupressores/uso terapêutico , Epitélio Pigmentado Ocular/transplante , Retina/cirurgia , Animais , Sobrevivência Celular/efeitos dos fármacos , Espaço Extracelular , Fundo de Olho , Linfócitos/patologia , Macrófagos/patologia , Masculino , Melaninas/metabolismo , Epitélio Pigmentado Ocular/metabolismo , Epitélio Pigmentado Ocular/patologia , Coelhos , Retina/patologia , Transplante Homólogo
14.
J Biol Chem ; 275(9): 6259-66, 2000 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-10692422

RESUMO

Cyclooxygenase-2 (COX-2), the enzyme primarily responsible for induced prostaglandin synthesis, is an immediate early gene induced by endotoxin in macrophages. We investigated the cis-acting elements of the COX-2 5'-flanking sequence, the transcription factors and signaling pathways responsible for transcriptional activation of the COX-2 gene in endotoxin-treated murine RAW 264.7 macrophages. Luciferase reporter constructs with alterations in presumptive cis-acting transcriptional regulatory elements demonstrate that the cyclic AMP-response element and two nuclear factor interleukin-6 (CCAAT/enhancer-binding protein (C/EBP)) sites of the COX-2 promoter are required for optimal endotoxin-dependent induction. In contrast, the E-box and NF-kappaB sites are not required for endotoxin-dependent induction. Inhibition of endotoxin-induced NF-kappaB activation by expression of an inhibitor-kappaB alpha mutant does not block endotoxin-dependent COX-2 reporter activity. Overexpression of c-Jun, C/EBPbeta, and C/EBPdelta enhances induction of the COX-2 reporter, while overexpression of cyclic AMP-response element-binding protein or "dominant negative" C/EBPbeta represses COX-2 induction. In addition, endotoxin rapidly and transiently elicits c-Jun phosphorylation in RAW 264.7 macrophages. Cotransfection of the COX-2 reporter with dominant negative expression vectors shows that endotoxin-induced COX-2 gene expression requires signaling through a Ras-independent pathway involving the adapter protein ECSIT and the signaling kinases MEKK1 and JNK. In contrast, endotoxin-induced COX-2 reporter activity is not blocked by overexpression of dominant-negative forms of Raf-1, ERK1, or ERK2.


Assuntos
Proteínas de Drosophila , Endotoxinas/farmacologia , Isoenzimas/genética , MAP Quinase Quinase Quinase 1 , Macrófagos/efeitos dos fármacos , Prostaglandina-Endoperóxido Sintases/genética , Ativação Transcricional , Proteínas Adaptadoras de Transdução de Sinal , Animais , Proteínas Estimuladoras de Ligação a CCAAT , AMP Cíclico/genética , Ciclo-Oxigenase 2 , Proteínas de Ligação a DNA/genética , Genes Reporter , Proteínas I-kappa B/genética , Proteínas Quinases JNK Ativadas por Mitógeno , Lipopolissacarídeos/farmacologia , Camundongos , Proteínas Quinases Ativadas por Mitógeno/genética , Mutação , Proteínas Nucleares/genética , Fosforilação , Regiões Promotoras Genéticas , Proteínas Serina-Treonina Quinases/genética , Proteínas/genética , Proteínas Proto-Oncogênicas c-jun/metabolismo , Transdução de Sinais
15.
Eur J Ophthalmol ; 9(3): 217-30, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10544978

RESUMO

PURPOSE: To determine the long-term outcome of human retinal pigment epithelium (RPE) transplants in patients with advanced age-related macular degeneration (AMD). METHODS: Using pars plana microsurgical techniques, RPE allografts were transplanted subretinally to four groups of AMD patients: five patients received organized patch transplants after removal of choroidal neovascular membranes, four got small patch transplants in dry AMD; suspensions of RPE cells were transplanted in five cases with dry AMD, and two patients with RPE tears. None received immunosuppression. Transplants were followed for 24-38 months by biomicroscopy, fundus photography, SLO microperimetry, and fluorescein angiography. Rejection was defined as loss of visual function over the transplant, development of an exudative response (subretinal fluid with or without neovascularization), fluorescein leakage, and disruption, depigmentation, or encapsulation of the transplant. RESULTS: Four of 16 transplants (25%) presented no clinical signs of rejection. Three of the four small patch transplants remained pigmented and essentially unchanged after 30-32 months. Clinical signs of graft rejection appeared within three months in all cases of neovascular AMD (disrupted blood-retinal barrier, BRB), but after 6-20 months in five of nine eyes with non-exudative AMD (intact BRB). CONCLUSIONS: Subretinal human RPE allografts present a high rejection rate (75%) without immunosuppression. However, small extrafoveal transplants remained unchanged in shape, size and color for more than two years in non-exudative AMD. A disrupted BRB is likely to enhance graft rejection, which occurs earlier in exudative than in non-exudative AMD.


Assuntos
Degeneração Macular/cirurgia , Epitélio Pigmentado Ocular/transplante , Fatores Etários , Idoso , Feminino , Angiofluoresceinografia , Rejeição de Enxerto/imunologia , Humanos , Terapia de Imunossupressão , Masculino , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Oftalmológicos/métodos , Epitélio Pigmentado Ocular/embriologia , Gravidez , Fatores de Tempo , Transplante Homólogo , Resultado do Tratamento , Vitrectomia
16.
J Rheumatol ; 26(10): 2102-9, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10529124

RESUMO

OBJECTIVE: To determine the lowest effective starting dose and residual benefit of cyclosporine A (CSA) in patients with rheumatoid arthritis (RA) refractory to other agents. METHODS: In a double blind (masked observer), controlled, multicenter study, patients with RA started CSA 0 (placebo; n = 61), 1.5 (n = 89), or 2.5 (n = 94) mg/kg/day in a 21 week study that permitted dose escalation after 8 weeks, 1 week tapering of dose at 16 weeks, and post-therapy observation for 4 weeks. RESULTS: Patients with RA taking CSA 2.5 mg/kg/day fared better than those in the placebo or CSA 1.5 mg/kg/day groups in Patient Global Assessment, Examiner Global Assessment, Pain/Tender Joint Count and Index, Swollen Joint Count, and the "Ability at this moment" part of a modified Health Assessment Questionnaire. There was no difference in response between CSA 1.5 mg/kg/day and placebo groups. In the CSA 2.5 mg/kg/day group: improvement occurred between 8 and 12 weeks of therapy; average CSA dose escalation resulted in CSA 2.85 mg/kg/day by Week 16; benefit was not maintained during post-therapy observation and 7 patients discontinued the study because of an adverse event. Adverse events were common in all groups and included gastrointestinal discomfort, hypertension, and increased creatinine. Adverse events remitted with adjustment of dose or after washout in most patients. CONCLUSION: In RA, treatment of patients with CSA 2.5 mg/kg/day, but not 1.5 mg/kg/day, resulted in improvement of 4 of 5 primary efficacy variables when compared to placebo. Adverse events were mostly manageable. CSA was an effective therapy for patients with RA who had failed at least one second line agent.


Assuntos
Antirreumáticos/uso terapêutico , Artrite Reumatoide/tratamento farmacológico , Ciclosporina/uso terapêutico , Adulto , Antirreumáticos/administração & dosagem , Antirreumáticos/efeitos adversos , Ciclosporina/administração & dosagem , Ciclosporina/efeitos adversos , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
17.
Genes Dev ; 13(16): 2059-71, 1999 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-10465784

RESUMO

Activation of NF-kappaB as a consequence of signaling through the Toll and IL-1 receptors is a major element of innate immune responses. We report the identification and characterization of a novel intermediate in these signaling pathways that bridges TRAF6 to MEKK-1. This adapter protein, which we have named ECSIT (evolutionarily conserved signaling intermediate in Toll pathways), is specific for the Toll/IL-1 pathways and is a regulator of MEKK-1 processing. Expression of wild-type ECSIT accelerates processing of MEKK-1, whereas a dominant-negative fragment of ECSIT blocks MEKK-1 processing and activation of NF-kappaB. These results indicate an important role for ECSIT in signaling to NF-kappaB and suggest that processing of MEKK-1 is required for its function in the Toll/IL-1 pathway.


Assuntos
Proteínas de Drosophila , Proteínas de Insetos/metabolismo , MAP Quinase Quinase Quinase 1 , Glicoproteínas de Membrana/metabolismo , Proteínas/metabolismo , Receptores de Superfície Celular/metabolismo , Receptores Imunológicos , Receptores de Interleucina-1/metabolismo , Transdução de Sinais , Proteínas Adaptadoras de Transdução de Sinal , Sequência de Aminoácidos , Animais , Evolução Biológica , Linhagem Celular Transformada , Clonagem Molecular , Drosophila , Ativação Enzimática , Humanos , Camundongos , Dados de Sequência Molecular , NF-kappa B/metabolismo , Processamento de Proteína Pós-Traducional , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas/genética , Saccharomyces cerevisiae , Fator 6 Associado a Receptor de TNF , Receptores Toll-Like
18.
Acta Ophthalmol Scand ; 77(3): 247-54, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10406140

RESUMO

PURPOSE: To determine the long-term RPE allograft survival in the subretinal space using suspensions of RPE cells and atraumatic transplantation surgery. METHODS: Nineteen albino rabbits were transplanted with suspensions of pigmented RPE cells from brown rabbits. Following pars plana vitrectomy, the RPE cell suspension was injected through a small retinotomy using a glass micropipette into the subretinal space under microscopic control. No immunosuppression was used. The eyes were monitored by biomicroscopy, color fundus photography, and fluorescein angiography. Rabbits were sacrificed at 1, 3 and 6 months, respectively, and the eyes processed for light and electron microscopy, using monoclonal antibodies for identifying macrophages. RESULTS: Transplanted RPE cells were present in the subretinal space in all eyes at 6 months. There was no fluorescein leakage. Generally, the RPE allograft formed a monolayer, but focal fragmentation and disruption with dispersion of melanin pigment occurred. Foci of multilayers of cells in the subretinal space, containing large macrophages, were associated with adjacent photoreceptor damage. There was no infiltration of lymphocytes but macrophages and glial cells were contiguous to the transplant. Cells harboring intracytoplasmatic melanin pigment were observed in the neural retina. CONCLUSION: Transplantation of RPE cell suspensions to the subretinal space generally forms a monolayer that persists at 6 months. However, in areas of multilayers of RPE cells and macrophages, graft failure occurs in combination with adjacent photoreceptor damage. Graft failure is not associated with the infiltration of lymphocytes, but other mechanisms seem to occur.


Assuntos
Epitélio Pigmentado Ocular/transplante , Retina/cirurgia , Animais , Anticorpos Monoclonais , Angiofluoresceinografia , Seguimentos , Fundo de Olho , Sobrevivência de Enxerto , Macrófagos/imunologia , Masculino , Epitélio Pigmentado Ocular/imunologia , Epitélio Pigmentado Ocular/ultraestrutura , Coelhos , Retina/ultraestrutura , Transplante Homólogo
19.
Curr Opin Immunol ; 11(1): 13-8, 1999 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10047546

RESUMO

Innate immune recognition is mediated by a system of germline-encoded receptors that recognize conserved molecular patterns that are associated with microbial pathogens. These receptors are coupled to signal transduction pathways that control expression of a variety of inducible immune-response genes. Toll receptors and the associated signaling pathways of nuclear factor kappaB may represent the most ancient host defense system found in mammals, insects and plants.


Assuntos
Proteínas de Drosophila , Imunidade Inata/fisiologia , Glicoproteínas de Membrana/fisiologia , Receptores de Superfície Celular/fisiologia , Receptores Imunológicos , Animais , Humanos , Proteínas de Insetos/imunologia , Proteínas de Insetos/metabolismo , Glicoproteínas de Membrana/imunologia , Glicoproteínas de Membrana/metabolismo , Proteínas de Membrana/imunologia , Proteínas de Membrana/metabolismo , NF-kappa B/imunologia , NF-kappa B/metabolismo , Transdução de Sinais , Receptores Toll-Like
20.
Mol Cell ; 2(2): 253-8, 1998 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9734363

RESUMO

The Toll-mediated signaling cascade using the NF-kappaB pathway has been shown to be essential for immune responses in adult Drosophila, and we recently reported that a human homolog of the Drosophila Toll protein induces various immune response genes via this pathway. We now demonstrate that signaling by the human Toll receptor employs an adaptor protein, MyD88, and induces activation of NF-kappaB via the Pelle-like kinase IRAK and the TRAF6 protein, similar to IL-1R-mediated NF-kappaB activation. However, we find that Toll and IL-1R signaling pathways are not identical with respect to AP-1 activation. Finally, our findings implicate MyD88 as a general adaptor/regulator molecule for the Toll/IL-1R family of receptors for innate immunity.


Assuntos
Antígenos de Diferenciação , Glicoproteínas de Membrana , Proteínas de Membrana/metabolismo , Proteínas/metabolismo , Receptores de Superfície Celular , Receptores Imunológicos/metabolismo , Proteínas Adaptadoras de Transdução de Sinal , Animais , Drosophila , Proteínas de Drosophila , Humanos , Quinases Associadas a Receptores de Interleucina-1 , Proteínas de Membrana/imunologia , Fator 88 de Diferenciação Mieloide , NF-kappa B/metabolismo , Proteínas Quinases/metabolismo , Proteínas/química , Proteínas/genética , Receptores de Interleucina-1/metabolismo , Transdução de Sinais , Fator 6 Associado a Receptor de TNF , Receptores Toll-Like , Fator de Transcrição AP-1/metabolismo
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