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1.
J Laryngol Otol ; 135(3): 246-249, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33622427

RESUMO

BACKGROUND: Concerns have emerged regarding infection transmission during flexible nasoendoscopy. METHODS: Information was gathered prospectively on flexible nasoendoscopy procedures performed between March and June 2020. Patients and healthcare workers were followed up to assess for coronavirus disease 2019 development. One-sided 97.5 per cent Poisson confidence intervals were calculated for upper limits of risk where zero events were observed. RESULTS: A total of 286 patients were recruited. The most common indication for flexible nasoendoscopy was investigation of 'red flag' symptoms (67 per cent). Forty-seven patients (16 per cent, 95 per cent confidence interval = 13-21 per cent) had suspicious findings on flexible nasoendoscopy requiring further investigation. Twenty patients (7.1 per cent, 95 per cent confidence interval = 4.4-11 per cent) had new cancer diagnoses. Zero coronavirus disease 2019 infections were recorded in the 273 patients. No. 27 endoscopists (the doctors and nurses who carried out the procedures) were followed up.The risk of developing coronavirus disease 2019 after flexible nasoendoscopy was determined to be 0-1.3 per cent. CONCLUSION: The risk of coronavirus disease 2019 transmission associated with performing flexible nasoendoscopy in asymptomatic patients, while using appropriate personal protective equipment, is very low. Additional data are required to confirm these findings in the setting of further disease surges.


Assuntos
COVID-19/epidemiologia , COVID-19/transmissão , Endoscopia/efeitos adversos , Controle de Infecções/organização & administração , Transmissão de Doença Infecciosa do Paciente para o Profissional/prevenção & controle , Transmissão de Doença Infecciosa do Paciente para o Profissional/estatística & dados numéricos , Adulto , COVID-19/prevenção & controle , Endoscopia/instrumentação , Feminino , Humanos , Irlanda , Masculino , Seleção de Pacientes , Equipamento de Proteção Individual , Estudos Prospectivos , Estudos Retrospectivos , Medição de Risco
2.
Eye (Lond) ; 29(12): 1538-44, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26228291

RESUMO

PURPOSE: To compare 2.0 mg ranibizumab (RBZ) injections with 0.5 mg RBZ for eyes with center-involved diabetic macular edema (DME) and a central subfield thickness (CFT) of ≥250 µm on time-domain optical coherence tomography.DesignRandomized, controlled, multicenter clinical trial. METHODS: Eligible eyes were randomized in a 1:1 ratio to 0.5 mg (n=77) or 2.0 mg (n=75) RBZ. Study eyes received 6-monthly injections.Main outcome measuresThe primary outcome measure was the mean change in best corrected visual acuity (BCVA) at month 6. Secondary outcomes included the incidence and severity of systemic and ocular adverse events and the mean change in CFT from baseline. RESULTS: In all, 152 eyes (152 patients) were randomized in the study. At month 6, the mean improvement from baseline BCVA was +9.43 letters in the 0.5 mg RBZ group and +7.01 letters in the 2.0 mg RBZ group (P=0.161). At month 6, one death occurred in the 0.5 mg RBZ group and three deaths in the 2.0 mg RBZ group, all due to myocardial infarction in subjects with a prior history of heart disease. Mean CFT was reduced by 168.58 µm in the 0.5 mg RBZ group and by 159.70 µm in the 2.0 mg RBZ group (P=0.708). CONCLUSIONS: There was no statistically significant difference in the mean number of letters gained between the 0.5 and 2.0 mg RBZ groups through month 6. In this DME study population, high-dose RBZ does not appear to provide additional benefit over 0.5 mg RBZ.


Assuntos
Inibidores da Angiogênese/administração & dosagem , Retinopatia Diabética/tratamento farmacológico , Edema Macular/tratamento farmacológico , Ranibizumab/administração & dosagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Retinopatia Diabética/diagnóstico , Retinopatia Diabética/fisiopatologia , Método Duplo-Cego , Feminino , Seguimentos , Humanos , Injeções Intravítreas , Edema Macular/diagnóstico , Edema Macular/fisiopatologia , Masculino , Pessoa de Meia-Idade , Retina/patologia , Tomografia de Coerência Óptica , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores
4.
Retina ; 23(3): 299-306, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12824828

RESUMO

PURPOSE: To evaluate the use of ocular photodynamic therapy (OPT) with verteporfin in patients with choroidal neovascularization (CNV) from ocular histoplasmosis syndrome (OHS) and to compare these results with those for a natural history group. METHODS: A retrospective chart review was performed to identify cases of CNV secondary to OHS treated with OPT. Complete data were available for 38 of 41 eligible eyes. Data regarding the following variables were abstracted from the patient charts: demographic characteristics, previous surgery, angiographic features, number and timing of treatments with OPT, follow-up time, and visual acuity. The visual acuity results of eyes receiving photodynamic therapy were compared with those for a natural history cohort. RESULTS: On average, OHS patients who received treatment developed 0.88 line of visual improvement. Visual acuity improved or stayed the same in 69% (22 of 32) of eyes, improved by > or = 2 lines in 44% (14 of 32), and improved by > or = 4 lines in 22% (7 of 32). Patients who received OPT were 2.07 times more likely to have improved or constant vision than were those in the natural history group as described in one retrospective series (odds ratio = 2.07; 95% confidence interval, 0.78-5.56; P = 0.162). Thirty-eight percent (12 of 32) of eyes had undergone submacular surgery for CNV before any OPT. CONCLUSIONS: Ocular photodynamic therapy with verteporfin may be beneficial in patients with CNV secondary to OHS, even in the setting of previous submacular surgery.


Assuntos
Neovascularização de Coroide/tratamento farmacológico , Infecções Oculares Fúngicas/complicações , Histoplasmose/complicações , Fotoquimioterapia , Fármacos Fotossensibilizantes/uso terapêutico , Porfirinas/uso terapêutico , Adolescente , Adulto , Idoso , Neovascularização de Coroide/diagnóstico , Neovascularização de Coroide/etiologia , Feminino , Angiofluoresceinografia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Síndrome , Verteporfina , Acuidade Visual
5.
Ophthalmology ; 106(8): 1546-53, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10442903

RESUMO

OBJECTIVE: To evaluate the posterior segment findings seen in ocular cat scratch disease. DESIGN: Retrospective case series. PARTICIPANTS: There were 24 patients (35 eyes) with choroidal, retinal, or optic disc manifestations of Bartonella infection evaluated at the authors' institutions over a 6-year period. MAIN OUTCOME MEASURES: Clinical and photographic records were reviewed for evidence of disc edema, macular star, foci of retinitis or choroiditis, choroidal masses, optic nerve masses, vascular-occlusive events, or other findings. RESULTS: Discrete white retinal or choroidal lesions, 50 to 3000 microm in diameter, were the most common posterior segment findings in this series of patients (83% of eyes, 83% of patients). Optic disc swelling was the second most common finding (46% of eyes, 63% of patients) followed by a macular star (43% of eyes, 63% of patients). Vascular-occlusive events were also seen (14% of eyes, 21% of patients), and the site of occlusion was found to be intimately associated with the aforementioned retinal lesions. Final visual acuity was 20/25 or better in 26 (74%) of 35 eyes and was similar in both treated and untreated patients. CONCLUSION: Isolated foci of retinitis or choroiditis were the most common ocular manifestation of cat scratch disease in the authors' patient population, but an array of posterior segment findings may occur.


Assuntos
Doença da Arranhadura de Gato/diagnóstico , Corioidite/diagnóstico , Infecções Oculares Bacterianas/diagnóstico , Papiledema/diagnóstico , Retinite/diagnóstico , Adolescente , Adulto , Antibacterianos/uso terapêutico , Doença da Arranhadura de Gato/tratamento farmacológico , Criança , Corioidite/tratamento farmacológico , Infecções Oculares Bacterianas/tratamento farmacológico , Feminino , Fundo de Olho , Humanos , Masculino , Pessoa de Meia-Idade , Papiledema/tratamento farmacológico , Retinite/tratamento farmacológico , Estudos Retrospectivos , Transtornos da Visão/diagnóstico , Acuidade Visual
6.
Am J Ophthalmol ; 126(1): 134-5, 1998 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9683162

RESUMO

PURPOSE: To report two cases in which cystoid macular edema developed after initiation of topical latanoprost for glaucoma. METHODS: Case reports. One pseudophakic eye in each of two patients treated with latanoprost for glaucoma developed decreased vision and cystoid macular edema. Latanoprost was discontinued, and the cystoid macular edema was treated with topical corticosteroids and ketorolac. RESULTS: After discontinuing latanoprost and starting corticosteroids and ketorolac, visual acuity improved from counting fingers to 20/60 in one patient's left eye and from 20/100 to 20/25 in the other patient's right eye. The macular edema resolved in both eyes. CONCLUSIONS: Topical latanoprost may be associated with cystoid macular edema; this may be related to a prostaglandin-like action.


Assuntos
Glaucoma/tratamento farmacológico , Edema Macular/induzido quimicamente , Prostaglandinas F Sintéticas/efeitos adversos , Administração Tópica , Idoso , Idoso de 80 Anos ou mais , Anti-Inflamatórios não Esteroides/uso terapêutico , Feminino , Glucocorticoides/uso terapêutico , Humanos , Cetorolaco , Latanoprosta , Edema Macular/tratamento farmacológico , Masculino , Soluções Oftálmicas , Prednisolona/análogos & derivados , Prednisolona/uso terapêutico , Tolmetino/análogos & derivados , Tolmetino/uso terapêutico , Acuidade Visual
8.
Arch Ophthalmol ; 116(4): 470-4, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9565044

RESUMO

BACKGROUND: Active inflammation has not been traditionally associated with the ocular histoplasmosis syndrome. OBJECTIVE: To investigate the occurrence of presumed inflammatory chorioretinal lesions in patients with the ocular histoplasmosis syndrome. METHODS: Patients seen with acute symptoms and a clinical picture of ocular histoplasmosis were observed prospectively between August 13, 1993, and December 2, 1997. Symptoms, visual acuity, and fluorescein sodium angiography were used to document changes in inflammatory loci. RESULTS: Twelve patients were seen with active inflammatory lesions. Eleven had resolution of the loci with lessening of symptoms and improvement in acuity and angiographic findings. A typical subretinal neovascular membrane developed in 1 patient 8 months after the onset of symptoms. CONCLUSIONS: Inflammatory chorioretinal lesions can reactivate in the ocular histoplasmosis syndrome. In most of these patients, neovascularization did not develop and visual acuity was preserved.


Assuntos
Coriorretinite/microbiologia , Infecções Oculares Fúngicas/complicações , Histoplasmose/complicações , Doença Aguda , Adolescente , Adulto , Idoso , Coriorretinite/tratamento farmacológico , Coriorretinite/fisiopatologia , Infecções Oculares Fúngicas/tratamento farmacológico , Infecções Oculares Fúngicas/fisiopatologia , Feminino , Angiofluoresceinografia , Seguimentos , Fundo de Olho , Glucocorticoides/uso terapêutico , Histoplasmose/tratamento farmacológico , Histoplasmose/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Prednisona/uso terapêutico , Estudos Prospectivos , Recidiva , Neovascularização Retiniana/etiologia , Síndrome , Acuidade Visual/fisiologia
9.
Curr Opin Ophthalmol ; 6(3): 8-12, 1995 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10151086

RESUMO

The ocular histoplasmosis syndrome consists of punched-out, atrophic chorioretinal lesions, and peripapillary scarring in the absence of vitreal inflammation. Choroidal neovascularization is the cause of significant visual loss in involved eyes and is estimated to occur in up to 5% of affected eyes. An experimental primate model has given us a better understanding of the possible etiology and pathogenesis. Laser therapy for extrafoveal and juxtafoveal choroidal neovascularization has been shown to be effective. Recent advances in surgical technique and instrumentation have demonstrated the potential for the successful treatment of subfoveal choroidal neovascularization. The surgical specimens obtained from this approach have allowed for the study of the active process of neovascularization in this disease. This report summarizes our current knowledge regarding the pathogenesis and epidemiology of ocular histoplasmosis and the treatments currently utilized in the management of its associated choroidal neovascularization.


Assuntos
Doenças da Coroide/microbiologia , Infecções Oculares Fúngicas/etiologia , Histoplasmose/etiologia , Doenças Retinianas/microbiologia , Animais , Atrofia , Corioide/irrigação sanguínea , Corioide/patologia , Doenças da Coroide/patologia , Doenças da Coroide/cirurgia , Infecções Oculares Fúngicas/patologia , Infecções Oculares Fúngicas/cirurgia , Fóvea Central , Histoplasmose/patologia , Histoplasmose/cirurgia , Humanos , Fotocoagulação a Laser , Macaca , Neovascularização Patológica/microbiologia , Neovascularização Patológica/cirurgia , Retina/patologia , Doenças Retinianas/patologia , Doenças Retinianas/cirurgia
10.
Am J Ophthalmol ; 118(4): 457-62, 1994 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-7943123

RESUMO

We treated a patient with reactive lymphoid hyperplasia in whom the diagnosis was made by chorioretinal biopsy. Histopathologic examination and culture of the biopsied specimen allowed us to rule out a neoplastic or infectious process. The biopsy result allowed us to treat him with systemic corticosteroid alone, thus avoiding the potential harmful side effects of other medications, including antituberculous drugs. There were no surgical or postoperative complications. This study confirms the usefulness of chorioretinal biopsy for establishing a diagnosis and formulating a rational treatment plan.


Assuntos
Corioide/patologia , Pseudotumor Orbitário/patologia , Retina/patologia , Antígenos CD/análise , Biópsia , Corioide/diagnóstico por imagem , Angiofluoresceinografia , Fundo de Olho , Humanos , Hiperplasia , Masculino , Pessoa de Meia-Idade , Prednisona/uso terapêutico , Ultrassonografia
11.
Am J Ophthalmol ; 117(1): 13-8, 1994 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-8291587

RESUMO

Twenty-nine patients (30 eyes) with pseudo-opercula were followed up for six to 65 months (mean, 24 months). Visual acuity was 20/30 or better in all but one eye that was amblyopic. Only one eye developed a decrease in visual acuity and changes interpreted as a stage 1 (foveal detachment induced by tangential traction of the cortical vitreous) impending hole. After vitrectomy visual acuity returned to 20/20. Ultrasonographic examination confirmed the presence of pseudo-opercula in all 22 eyes examined. We concluded that the a pseudo-operculum is a favorable prognostic sign and that its presence is demonstrable ultrasonographically.


Assuntos
Macula Lutea/diagnóstico por imagem , Perfurações Retinianas/diagnóstico por imagem , Corpo Vítreo/diagnóstico por imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Oftalmopatias/diagnóstico por imagem , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Perfurações Retinianas/etiologia , Perfurações Retinianas/fisiopatologia , Ultrassonografia , Acuidade Visual , Corpo Vítreo/fisiopatologia
12.
South Med J ; 87(1): 97-8, 1994 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8284730

RESUMO

We present this case to emphasize the potentially fatal outcome of supraventricular tachycardia in infancy, particularly if it has been undiagnosed for several days. Certainly, careful monitoring needs to take place during any attempt at cardioversion or any other noxious stimulation of the patient. Bicarbonate therapy should be provided if metabolic acidosis is present. Restoration of sinus rhythm may not guarantee an immediate return of normal cardiac function.


Assuntos
Parada Cardíaca/etiologia , Taquicardia Supraventricular/complicações , Humanos , Lactente , Masculino , Remissão Espontânea , Choque Cardiogênico/etiologia
13.
Ophthalmology ; 100(12): 1846-50, 1993 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8259285

RESUMO

PURPOSE: Accidental skin puncture carries the risk of both hepatitis B and human immunodeficiency virus transmission. There have been studies of the incidence of these skin punctures in general surgery, but no study has focused on ophthalmic surgery. METHOD: All incident reports of skin punctures in the Bascom Palmer Eye Institute operating rooms from January 1990 through November 1991 were reviewed retrospectively. The incidence of skin puncture also was studied propsectively from December 1991 through May 1992. During the prospective phase, the healthcare worker was asked to complete an anonymous form regarding the instrument involved, whether it was clean or contaminated, the persons involved, and whether the room lights were on or off. RESULTS: There were 37 such occurrences in 14,878 operations (0.25%) during the retrospective study and 12 in 4246 operations (0.28%) in the prospective period. In only one case was the instrument contaminated by contact with a patient known to have positive serology for the human immunodeficiency virus. There were no documented seroconversions of healthcare personnel for either hepatitis B or human immunodeficiency virus. In 63% of these occurrences, the penetrating instrument was known to be definitely contaminated with the patient's blood. Only one person was handling the instrument 84% of the time. CONCLUSION: The low but present danger to ophthalmic personnel during surgical procedures justifies precautions to decrease the occurrence of skin punctures.


Assuntos
Acidentes de Trabalho/estatística & dados numéricos , Oftalmologia/estatística & dados numéricos , Pele/lesões , Instrumentos Cirúrgicos/efeitos adversos , Ferimentos Perfurantes/epidemiologia , Feminino , Florida/epidemiologia , Humanos , Incidência , Masculino , Estudos Retrospectivos , Fatores de Risco , Ferimentos Perfurantes/etiologia
14.
Arch Ophthalmol ; 111(6): 789-94, 1993 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7685589

RESUMO

OBJECTIVE: We undertook a retrospective study of all choroidal nevi with overlying neovascularization seen at Bascom Palmer Eye Institute, Miami, Fla, to determine long-term effects on vision and whether the presence of neovascularization represented increased malignant potential of the lesion. DESIGN: A computer search of patients with a coded diagnosis of both a choroidal nevus and choroidal neovascularization was performed. Cases in which the neovascularization was directly overlying the nevus were used for the study. RESULTS: The records of 23 patients followed up for a mean of 6.5 years were reviewed for visual acuity, effect of treatment, and change in the size of the choroidal lesion. Fifteen of the 23 patients had a final visual acuity in the affected eye of 20/200 or better. Five of six patients treated with laser had visual improvement of 2 or more lines. Only one of these lesions showed any growth, and this was after 17 years of no growth. CONCLUSIONS: Choroidal neovascularization associated with choroidal nevi can have profound effects on vision. Laser treatment, when indicated, is effective and may be safely performed. The clinical course of these lesions, to date, does not indicate any clinically significant malignant transformation.


Assuntos
Neoplasias da Coroide/complicações , Corioide/irrigação sanguínea , Neovascularização Patológica/complicações , Nevo Pigmentado/complicações , Adulto , Idoso , Idoso de 80 Anos ou mais , Corioide/patologia , Neoplasias da Coroide/patologia , Feminino , Angiofluoresceinografia , Seguimentos , Fundo de Olho , Humanos , Fotocoagulação a Laser , Masculino , Pessoa de Meia-Idade , Neovascularização Patológica/patologia , Neovascularização Patológica/cirurgia , Nevo Pigmentado/patologia , Estudos Retrospectivos , Acuidade Visual
16.
Ophthalmology ; 99(11): 1678-85, 1992 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-1280798

RESUMO

BACKGROUND: Several recent articles have described syndromes in which there is enlargement of the blind spot associated with retinal lesions. These have included the multiple evanescent white dot syndrome, acute macular neuroretinopathy, acute idiopathic blind spot enlargement syndrome, and multifocal choroiditis or pseudo presumed ocular histoplasmosis syndrome (pseudo POHS). METHODS: The authors reviewed the records of seven patients in whom signs and symptoms of acute enlargement of the blind spot and pseudo POHS developed. RESULTS: All seven patients had photopsia accompanying enlargement of the blind spot during their illness. Four had transient white spots as seen in the multiple evanescent white dot syndrome. All presented with or developed chorioretinal scars or neovascularization similar to that seen in multifocal choroiditis or pseudo POHS. In four of the seven patients, POHS-like scars developed only in the eye that was symptomatic with blind spot enlargement and photopsia. Five of the 7 had visual acuity of 20/25 or better at the last follow-up. CONCLUSION: It would appear that there is an overlap in the clinical findings of all of these syndromes and that there may be a common link in their etiology.


Assuntos
Corioide/irrigação sanguínea , Corioidite/etiologia , Neovascularização Patológica/etiologia , Disco Óptico/patologia , Adulto , Feminino , Angiofluoresceinografia , Fundo de Olho , Humanos , Hipertrofia , Masculino , Doenças Retinianas/complicações , Síndrome , Acuidade Visual , Campos Visuais
17.
Arch Ophthalmol ; 110(5): 675-80, 1992 May.
Artigo em Inglês | MEDLINE | ID: mdl-1580843

RESUMO

Diffuse unilateral subacute neuroretinitis is an endemic disease associated with severe visual loss in the southeastern and midwestern United States and the Caribbean. It is caused by a single nematode that may wander in the subretinal space for many months or years. Until recently, the only effective treatment has involved the difficult and time-consuming biomicroscopic detection of the worm followed by photocoagulation. This report describes the use of oral thiabendazole in four patients with presumed diffuse, unilateral, subacute neuroretinitis. Serial fundus photography was used to detect evidence of early destruction of the worm.


Assuntos
Infecções por Nematoides/tratamento farmacológico , Neurite Óptica/etiologia , Retinite/etiologia , Tiabendazol/uso terapêutico , Administração Oral , Adolescente , Animais , Criança , Feminino , Fundo de Olho , Humanos , Masculino , Nematoides/isolamento & purificação , Infecções por Nematoides/parasitologia , Neurite Óptica/patologia , Retina/parasitologia , Retinite/patologia
18.
Transplantation ; 51(6): 1258-62, 1991 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-2048199

RESUMO

Male-specific, H-Y antigen is a widely utilized antigen system for analyzing the role of non-MHC transplantation antigens in graft rejection. In this study, we examined the role of H-Y antigen in corneal graft rejection. Orthotopic corneal grafts from male LBNF1 rats were transplanted to syngeneic female LBNF1 recipients. The male corneal grafts survived beyond 100 days on naive female recipients. In other experiments, hosts bearing clear male corneal grafts and systemically immunized with subcutaneous inoculations of male splenocytes followed by full-thickness male skin grafts failed to reject their corneal grafts, even though the male skin grafts were swiftly rejected. The inability of female hosts to reject existing male corneal grafts suggested that the cornea failed to express H-Y transplantation antigen. Further experiments, however, revealed that male-specific antigen was expressed on corneal grafts. Hosts bearing clear male grafts in the left eye rejected subsequent male skin grafts and promptly rejected male corneal grafts transplanted to the contralateral eye. Interestingly, the original male corneal grafts remained clear during the rejection of both the skin graft and the second corneal graft. The results indicate that corneal grafts representing minor histocompatibility disparities enjoy immunologic privilege in the naive host, even if the host is subsequently immunized systemically.


Assuntos
Transplante de Córnea/imunologia , Antígeno H-Y/imunologia , Animais , Feminino , Rejeição de Enxerto , Sobrevivência de Enxerto , Histocompatibilidade , Imunização , Masculino , Ratos , Pele/imunologia , Baço/imunologia
19.
Transplantation ; 51(2): 532-6, 1991 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-1994550

RESUMO

While the immune privilege nature of the eye affords significant protection to corneal grafts, immunologic rejection is the leading cause of graft failure. Class II antigens are normally absent or expressed at very low levels in normal cornea. The role that class II antigens play in causing graft rejection is particularly interesting. Class II molecules are present on many cells of the immune system, and therefore are important in modulating and mediating immune reactions. The absence of class II bearing cells in the cornea leads to the interesting issue of whether or not those antigens can induce immune rejection of a corneal graft. In the current study we have made use of a pair of congenic rat strains that differ only at class II loci to determine the impact of these antigens on corneal graft survival. Central corneal grafts were not rejected. Recipients preimmunized with skin grafts rejected 100% of the class II disparate corneas with a median survival time (MST) of 15.5 days. When class II disparate Langerhans-cell-containing (LC+) corneas were grafted, the corneas were not rejected, but they immunized the recipients as evidenced by the rejection of a second corneal graft on the contralateral eye. Immunofluorescent stains demonstrated transient expression of class II antigens on graft epithelium after transplantation. This temporary appearance of class II provides a target for rejection in the preimmunized animals but is of insufficient duration to both prime naive animals and provide a target for antigraft effectors.


Assuntos
Transplante de Córnea/imunologia , Antígenos de Histocompatibilidade Classe II/imunologia , Animais , Sobrevivência de Enxerto , Células de Langerhans/imunologia , Ratos , Ratos Endogâmicos , Fatores de Tempo
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