RESUMO
PURPOSE: To evaluate the ability of phacoemulsifiers with active versus passive infusion fluidics control systems to maintain target intraocular pressures (IOPs) under varying flow conditions. SETTING: Alcon Research, Ltd., Lake Forest, California, USA. DESIGN: Experimental study. METHODS: An acrylic test chamber was used to model the anterior chamber of the eye. Two passive (gravity-based) systems were tested using bottle heights yielding infusion pressures of 41, 75, and 109 cm of water under zero-flow conditions. One actively controlled system was tested using equivalent target IOPs of 30, 55, and 80 mm Hg. Test chamber IOPs were measured at aspiration flow rates of 15, 30, 45, and 60 cc/min. RESULTS: The measured flow rates were similar between fluidics systems across the range of intended aspiration flow rates. All systems achieved the desired target IOPs under zero-flow conditions. After activation of aspiration flow, however, measured IOPs decreased from target IOPs for the 2 passive systems. Each 15 cc/min increase in the aspiration flow rate produced a pressure drop of 14.0 to 16.2 mm Hg or 9.3 to 14.2 mm Hg, depending on the system. Measured IOPs in the actively controlled system closely matched the targeted IOPs across all tested aspiration flow rates, deviating from targets by no more than 4.3 mm Hg. CONCLUSIONS: All phacoemulsification aspiration infusion fluidics systems achieved target IOPs under zero-flow conditions. Only the actively controlled system maintained target IOPs across a range of aspiration flow rates. These experimental findings suggest that anterior chamber stability might be better in the clinical setting using an actively controlled system. FINANCIAL DISCLOSURE: Dr. Dimalanta is an employee of Alcon Research, Ltd. Dr. Miller is an investigator and speaker for and a consultant to Alcon Laboratories, Inc. Dr. Nicoli has no financial or proprietary interest in any material or method mentioned.
Assuntos
Acetatos/administração & dosagem , Câmara Anterior/anatomia & histologia , Pressão Intraocular/fisiologia , Minerais/administração & dosagem , Soluções Oftálmicas/administração & dosagem , Facoemulsificação , Cloreto de Sódio/administração & dosagem , Complacência (Medida de Distensibilidade) , Combinação de Medicamentos , Humanos , Hidrodinâmica , SucçãoRESUMO
PURPOSE: To evaluate the safety and efficacy of Morcher 50F iris diaphragm implantation to manage moderate to large defects of the human iris. SETTING: Stein Eye Institute, UCLA, Los Angeles, California, USA. DESIGN: Prospective nonrandomized interventional case series. METHODS: The demographic, preoperative, and postoperative data of patients who had implantation of modified capsular tension rings and followed to 1 year were reviewed. Safety measures included loss of corrected distance visual acuity (CDVA), surgical complications, adverse events, and secondary surgical interventions. Efficacy measures included CDVA with glare, daytime and nighttime glare symptom scores, and subjective cosmesis scores. RESULTS: The study comprised 12 patients. The median CDVA was 20/70 before surgery and 20/20 after surgery. There were no lost lines of CDVA and no intraoperative complications. The most common postoperative complication was posterior capsule opacification. Two adverse events were unrelated to the device. Four patients had secondary surgical interventions, the most common of which was laser capsulotomy. The median CDVA with glare improved from less than 20/400 before surgery to 20/50 after surgery. One patient worsened. The median subjective daytime glare symptom score improved from 9 to 3 on a 10-point scale (P = .001). The median nighttime subjective glare symptom score improved from 8 to 2 (P = .001). The subjective cosmetic appearance of the eye stayed the same or improved for all patients (P = .031). CONCLUSION: Iris diaphragm implantation was relatively safe and effective for reducing light and glare sensitivity in eyes with iris defects when combined with cataract extraction and intraocular lens implantation. FINANCIAL DISCLOSURE: None of the authors has a financial or proprietary interest in any material or method mentioned.
Assuntos
Implante de Lente Intraocular , Lentes Intraoculares , California , Catarata , Extração de Catarata , Humanos , Iris , Complicações Pós-Operatórias , Estudos Prospectivos , Próteses e Implantes , Estudos RetrospectivosRESUMO
An unusual case of spontaneous corneal perforation of acute hydrops in the left eye of a 21-year-old man is presented. The patient had a history of atopic diseases. To evaluate the status of the other eye, corneal topographic analysis was performed. This confirmed a subclinical keratoconus in the fellow eye and the association with atopy, eye rubbing, and rapid progression of the ectasia leading to perforation.
Assuntos
Edema da Córnea/complicações , Edema da Córnea/patologia , Topografia da Córnea , Ceratocone/complicações , Acetazolamida/uso terapêutico , Doença Aguda , Adulto , Edema da Córnea/tratamento farmacológico , Lâmina Limitante Posterior/efeitos dos fármacos , Lâmina Limitante Posterior/patologia , Quimioterapia Combinada , Endotélio Corneano/efeitos dos fármacos , Endotélio Corneano/patologia , Humanos , Ceratocone/tratamento farmacológico , Masculino , Ruptura Espontânea , Timolol/uso terapêutico , Acuidade VisualRESUMO
An unusual case of bilateral acute endophthalmitis in association with the HLA-DQ5 histocompatibility antigen is reported. A 35-year-old woman with high myopia and cataracts in both eyes underwent phacoemulsification procedures performed in separate sessions using different viscoelastic substances and following the same strict prophylactic measures. After each surgical procedure, she developed S. epidermidis acute endophthalmitis in the right eye and Propionibacterium acnes acute endophthalmitis in the left eye; both were successfully treated with capsular bag irrigation and intracameral vancomycin (1 mg/0.1 mL). She tested positive for the HLA-DQ5 (DQ1), DQ2 antigen. The question is raised as to whether the HLA-DQ5 histocompatibility antigen may be a predisposing factor for both staphylococcal and P. Acnes acute endophthalmitis. A multicenter prospective study is proposed to identify this HLA antigen in all patients scheduled for cataract surgery who have a history of postoperative endophthalmitis in the fellow eye.
Assuntos
Endoftalmite/microbiologia , Infecções Oculares Bacterianas , Infecções por Bactérias Gram-Positivas , Antígenos HLA-DQ/análise , Complicações Pós-Operatórias/microbiologia , Propionibacterium acnes/isolamento & purificação , Staphylococcus epidermidis/isolamento & purificação , Doença Aguda , Adulto , Antibacterianos/uso terapêutico , Humor Aquoso/microbiologia , Extração de Catarata , Endoftalmite/tratamento farmacológico , Endoftalmite/genética , Infecções Oculares Bacterianas/tratamento farmacológico , Infecções Oculares Bacterianas/genética , Infecções Oculares Bacterianas/microbiologia , Feminino , Predisposição Genética para Doença , Infecções por Bactérias Gram-Positivas/tratamento farmacológico , Infecções por Bactérias Gram-Positivas/genética , Infecções por Bactérias Gram-Positivas/microbiologia , Humanos , Implante de Lente Intraocular , Complicações Pós-Operatórias/tratamento farmacológico , Vancomicina/uso terapêuticoRESUMO
Tissue damage by ischemia/reperfusion (I/R) results from a temporary cessation of blood flow followed by the restoration of circulation. The injury depresses mitochondrial respiration, increases the production of reactive oxygen species (ROS), decreases the mitochondrial transmembrane potential, and stimulates invasion by inflammatory cells. The primary objective of this work was to address the potential use of bone marrow stem cells (BMSCs) to preserve and restore mitochondrial function in the kidney after I/R. Mitochondria from renal proximal tubule cells were isolated by differential centrifugation from rat kidneys subjected to I/R (clamping of renal arteries followed by release of circulation after 30 min), without or with subcapsular administration of BMSCs. Respiration starting from mitochondrial complex II was strongly affected following I/R. However, when BMSCs were injected before ischemia or together with reperfusion, normal electron fluxes, electrochemical gradient for protons, and ATP synthesis were almost completely preserved, and mitochondrial ROS formation occurred at a low rate. In homogenates from cultured renal cells transiently treated with antimycin A, the coculture with BMSCs induced a remarkable increase in protein S-nitrosylation that was similar to that found in mitochondria isolated from I/R rats, evidence that BMSCs protected against both superoxide anion and peroxynitrite. Labeled BMSCs migrated to damaged tubules, suggesting that the injury functions as a signal to attract and host the injected BMSCs. Structural correlates of BMSC injection in kidney tissue included stimulus of tubule cell proliferation, inhibition of apoptosis, and decreased inflammatory response. Histopathological analysis demonstrated a score of complete preservation of tubular structures by BMSCs, associated with normal plasma creatinine and urinary osmolality. These key findings shed light on the mechanisms that explain, at the mitochondrial level, how stem cells prevent damage by I/R. The action of BMSCs on mitochondrial functions raises the possibility that autologous BMSCs may help prevent I/R injuries associated with transplantation and acute renal diseases.
Assuntos
Trifosfato de Adenosina/metabolismo , Rim/metabolismo , Mitocôndrias/metabolismo , Animais , Masculino , Potencial da Membrana Mitocondrial/fisiologia , Estresse Oxidativo/fisiologia , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo , Traumatismo por Reperfusão/metabolismo , Células-Tronco/citologia , Células-Tronco/metabolismoRESUMO
The aim of this study was to apply the protocol for the shelf life prediction of bakery products proposed by Calligaris and others (2007a) on bread sticks. The methodology comprises 4 steps: (1) evaluation of the physical properties of fat; (2) performing the accelerated shelf life test; (3) evaluation of sensory acceptance limit and the relevant chemical index limit; (4) setting up the shelf life prediction model. The results allow validating the shelf life prediction methodology proposed. In fact, the peroxide number was found to be a representative index of the quality depletion of bread sticks during their shelf life. In addition, once again by accounting for the changes in the fat physical state, it is possible to set up a modified Arrhenius equation able to describe the temperature dependence of peroxide formation. Finally, a mathematical model to simply and quickly calculate the shelf life of bread sticks has been developed.
Assuntos
Pão/normas , Conservação de Alimentos/normas , Peroxidação de Lipídeos , Peróxidos/análise , Pão/análise , Fenômenos Químicos , Físico-Química , Humanos , Matemática , Modelos Teóricos , Oxirredução , Valor Preditivo dos Testes , Controle de Qualidade , Paladar , Fatores de TempoRESUMO
PURPOSE: To analyze the effect of glaucomatocyclitic crisis on the optic nerve head, as well as its consequent structural and hemodynamic changes. To evaluate the surgical indication for Posner-Schlossman syndrome. MATERIALS AND METHODS: Four Posner-Schlossman syndrome cases were evaluated for an analysis of the phenomena occurring in the optic disc by means of retinal confocal tomography and Scanning Laser Doppler Flowmetry, and their correlation with visual function as measured with automated computerized perimetry. In all cases the images were obtained in the mediate period after the attack, while in case 1, measurements were performed in the immediate and mediate periods before, during and after the attack. RESULTS: Significant differences were found between optic nerve head parameters and retinal flow measurements in the different phases evaluated. No permanent optic nerve head damage was demonstrated in any of the cases studied, except for case 4 (Posner-Schlossman syndrome associated with traumatic glaucoma). All the variables analyzed returned to normal values after remission of the acute rise in intraocular pressure. CONCLUSIONS: During the attacks of ocular hypertension the optic nerve head experiences significant morphologic changes and hemodynamic variations; nevertheless since they are transient, they fail to cause permanent damage. There was only one case, in which there was optic disc damage and visual field loss. It can be concluded that surgery should be restricted to those cases with severe and disabling symptoms (relative surgical indication) or to cases with progressive optic neuropathy with visual field loss, when the syndrome is associated with glaucoma (absolute surgical indication).
Assuntos
Glaucoma de Ângulo Aberto/fisiopatologia , Pressão Intraocular , Iridociclite/fisiopatologia , Disco Óptico/irrigação sanguínea , Disco Óptico/fisiopatologia , Velocidade do Fluxo Sanguíneo , Glaucoma de Ângulo Aberto/cirurgia , Humanos , Fluxometria por Laser-Doppler , Microscopia Confocal , Estudos Prospectivos , Síndrome , Tomografia , Testes de Campo Visual , Campos VisuaisRESUMO
We studied 81 patients with chronic hepatitis C to investigate the relationship between iron and alpha-interferon response. Sixty-one patients (group A) were given alpha-interferon irrespective of iron status, whereas 20 (group B) with iron overload, were iron depleted before alpha-interferon therapy. In group A, 21 patients responded to alpha-interferon and 40 were non-responders. Increased iron indices were significantly more frequent in non-responders than responders. Multivariate analysis showed that among the independent variables evaluated, only gamma-GT and liver iron concentration predicted therapy outcome. After phlebotomy treatment, serum alanine aminotransferase fell significantly both in patients of group B (196 +/- 122 IU/l vs 82 +/- 37 IU/l, p < 10(-6)) and in 12 non-responders of group A (198 +/- 89 IU/l vs 107 +/- 81 IU/l, p < 10(-6)). In 16 iron depleted patients, eight from each group, subsequent treatment with alpha-interferon produced a response in only one patient. These results suggest that increased liver iron is a negative prognostic factor for alpha-interferon response in chronic hepatitis C. Iron depletion had a beneficial effect on serum alanine aminotransferase in all the patients treated, but did not improve the response to alpha-interferon.
Assuntos
Hepatite C/metabolismo , Interferon-alfa/uso terapêutico , Ferro/metabolismo , Adulto , Idoso , Alanina Transaminase/sangue , Alanina Transaminase/metabolismo , Feminino , Ferritinas/sangue , Ferritinas/metabolismo , Hepatite C/terapia , Humanos , Deficiências de Ferro , Sobrecarga de Ferro/metabolismo , Fígado/química , Fígado/metabolismo , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Flebotomia , Prognóstico , Transferrina/metabolismo , gama-GlutamiltransferaseRESUMO
We evaluate the relation between genotype and phenotype in 47 Italian male patients with homozygous genetic hemochromatosis (GH). Phenotype evaluation was based on the ratio of amount of iron removed (IR) by phlebotomy and age (IR/age). Patients were divided in two classes of phenotype expression: class I included 26 patients with less severe iron overload (IR/age <0.33) and class II included 21 patients with a more marked one (IR/age >0.33). Genetic variability was assessed by haplotype analysis combining alleles at HLA-B, D6S265, HLA-A, and D6S105 loci. A common ancestral haplotype carrying D6S265-1, HLA-A3, and D6S105-8 alleles was present in 13 of 52 (25%) chromosomes in class I and in 24 of 42 (57%) chromosomes in class II (P = .0027). Homozygotes and heterozygotes for the ancestral haplotype had higher iron indices than patients carrying two haplotypes other than the ancestral one. Seven of the eight patients homozygous for the ancestral haplotype were in class II, heterozygotes were equally distributed between the two classes, whereas 14 of 18 carriers of other haplotype combinations were in class I. Our results suggests that the gene defect linked to the ancestral haplotype is the result of a single, severe mutation. The high variability of phenotype expression in heterozygotes for the ancestral haplotype could be accounted for the contribution of the mutation carried by the second haplotype. Combination of different mutations could be responsible for the variable degrees of iron overload found in patients with GH.
Assuntos
Antígenos HLA-A/genética , Antígenos HLA-B/genética , Hemocromatose/genética , Adulto , Idoso , Mapeamento Cromossômico , Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/genética , Ferritinas/sangue , Genes MHC Classe I , Triagem de Portadores Genéticos , Variação Genética , Haplótipos , Hemocromatose/sangue , Hemocromatose/imunologia , Homozigoto , Humanos , Ferro/metabolismo , Itália , Fígado/patologia , Cirrose Hepática/etiologia , Cirrose Hepática/genética , Cirrose Hepática/patologia , Masculino , Pessoa de Meia-Idade , Fenótipo , Transferrina/análiseAssuntos
Túnica Conjuntiva/patologia , Oftalmopatias/patologia , Hemorragia , Linfangiectasia/patologia , Adulto , Feminino , HumanosAssuntos
Coriorretinite/etiologia , Toxoplasmose Ocular/complicações , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-IdadeAssuntos
Oftalmopatias/diagnóstico por imagem , Nervo Óptico/diagnóstico por imagem , Retina/diagnóstico por imagem , Adulto , Angiografia , Pré-Escolar , Neoplasias Oculares/diagnóstico por imagem , Feminino , Fluoresceínas , Humanos , Masculino , Pessoa de Meia-Idade , Retina/anormalidades , Retina/irrigação sanguíneaRESUMO
Se describe la tecnica de Ritch y Podos para realizar la iridectomia con laser. Se presento el resultado obtenido en 18 ojos.Se propone un metodo para evitar el problema de la "carbonizacion"