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1.
Transpl Infect Dis ; 21(4): e13097, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31002443

RESUMO

Endotipsitis is a rare but severe complication of transjugular intrahepatic portosystemic shunt (TIPS), a device widely used to treat portal hypertension in adults, but sparsely used in children. We report a case of endotipsitis in a 3-year-old child affected of biliary atresia. She underwent a Kasai procedure at 3 months of age but, although the bile flow was restored, she presented upper gastrointestinal bleeding due to portal hypertension 1.5 years later. A TIPS was placed in order to control the hemorrhage. A year after TIPS placement, she started presenting repeated episodes of cholangitis. Blood cultures were positive to Enterobacter cloacae. Even with long antibiotic courses, adjusted to blood cultures, infectious signs were observed after antibiotic withdrawal. Device infection was demonstrated through Positron emission tomography-Computed tomography scan. The patient was listed for liver transplantation, and intravenous antibiotic treatment was maintained until stent removal during the liver transplant 8 months later. No infectious complications were demonstrated after the surgery. To the best of our knowledge, this is the first case report of endotipsitis described in a pediatric patient.


Assuntos
Colangite/microbiologia , Transplante de Fígado , Derivação Portossistêmica Transjugular Intra-Hepática/efeitos adversos , Antibacterianos/uso terapêutico , Atresia Biliar/complicações , Pré-Escolar , Colangite/diagnóstico , Colangite/tratamento farmacológico , Enterobacter cloacae/efeitos dos fármacos , Infecções por Enterobacteriaceae/tratamento farmacológico , Feminino , Hemorragia Gastrointestinal/terapia , Humanos
2.
An. pediatr. (2003. Ed. impr.) ; 90(3): 141-147, mar. 2019. tab, graf
Artigo em Espanhol | IBECS | ID: ibc-178366

RESUMO

Introducción: El objetivo del estudio fue evaluar la seguridad y la eficacia de la combinación de ledipasvir/sofosbuvir en la infección crónica por el genotipo 1 y 4 del virus de la hepatitis C (VHC) en pacientes pediátricos. Métodos: Se incluyó a pacientes de entre 6 y 18 años. La duración y la dosis de los fármacos antivirales se administraron según la edad del paciente, el estadio de fibrosis y los tratamientos previos con interferón pegilado y ribavirina. La variable principal de eficacia fue el porcentaje de pacientes con una respuesta virológica sostenida 12 semanas (RVS12) después del tratamiento. Resultados: Nueve pacientes con una mediana de edad de 14,8 años (8,48-17,91) fueron tratados con combinación de ledipasvir/sofosbuvir. Cinco pacientes habían recibido previamente tratamiento con interferón pegilado + ribavirina. Ocho pacientes tenían algún grado de fibrosis. La mediana de la carga viral previa al tratamiento fue de 6,2 log (5,9-6,8) con negativización del ARN del VHC 6 semanas después de comenzar el tratamiento en el 100% de los pacientes. Todos los pacientes mantuvieron una respuesta viral sostenida a las 12 semanas. Tres pacientes (33,3%) tuvieron algún tipo de efecto adverso (2 dolores de cabeza y un afta oral). La mediana de seguimiento posterior al tratamiento fue de 24 semanas (12-104). Conclusiones: El tratamiento con ledipasvir/sofosbuvir en pacientes pediátricos con infección crónica por VHC de genotipo 1 y 4 es seguro y efectivo con RVS12, similar a lo reportado en adultos


Introduction: Hepatitis C virus infection is world health problem. The aim of this study was to assess the safety and efficacy of ledipasvir/sofosbuvir combination in chronic Hepatitis C Virus (HCV) genotype 1 and 4 infection in paediatric patients. Methods: Eligible patients to be treated with ledipasvir/sofosbuvir were patients from 6 to 18 years old with a chronic HCV genotype 1 or 4 infection. The duration and doses of antiviral drugs were changed depending on patient age, fibrosis stage, and PEGylated interferon+ribavirin experience status. The primary efficacy endpoint was the percentage of patients with a sustained virological response 12 weeks post-treatment. Results: A total of nine patients (7 males) with a median age of 14.8 years (8.48-17.91) were treated with ledipasvir/sofosbuvir combination. Five patients received previous treatment with PEGylated interferon + ribavirin during a median of 8.5 months (3-12 months). Eight patients had some degree of fibrosis (1 patient presented with F1, three patients F2, 2 patients F3, and 2 patients F4). The median pre-treatment viral load was 6.2 Log [5.9-6.8] with the HCV RNA becoming negative six weeks after starting the treatment in 100% of the patients. All patients maintained a sustained viral response at 12 weeks. Three patients (33.3%) had some type of adverse effect (2 headache and one oral thrush). The median post-treatment follow-up was 24 weeks (12-104). Conclusions: Treatment with ledipasvir/sofosbuvir in paediatric patients with chronic HCV infection genotype 1 and 4 is safe and effective with SVR12 and similar to those reported in adults


Assuntos
Humanos , Masculino , Feminino , Criança , Adolescente , Infecção/tratamento farmacológico , Hepatite C/complicações , Hepatite C/tratamento farmacológico , Resultado do Tratamento , Sofosbuvir/uso terapêutico , Quimioterapia Combinada/métodos , Resposta Viral Sustentada , Antivirais/uso terapêutico , Estudos Prospectivos , Estudo Observacional
4.
An Pediatr (Barc) ; 90(3): 141-147, 2019 Mar.
Artigo em Espanhol | MEDLINE | ID: mdl-30126773

RESUMO

INTRODUCTION: Hepatitis C virus infection is world health problem. The aim of this study was to assess the safety and efficacy of ledipasvir/sofosbuvir combination in chronic Hepatitis C Virus (HCV) genotype 1 and 4 infection in paediatric patients. METHODS: Eligible patients to be treated with ledipasvir/sofosbuvir were patients from 6 to 18 years old with a chronic HCV genotype 1 or 4 infection. The duration and doses of antiviral drugs were changed depending on patient age, fibrosis stage, and PEGylated interferon+ribavirin experience status. The primary efficacy endpoint was the percentage of patients with a sustained virological response 12 weeks post-treatment. RESULTS: A total of nine patients (7 males) with a median age of 14.8 years (8.48-17.91) were treated with ledipasvir/sofosbuvir combination. Five patients received previous treatment with PEGylated interferon+ribavirin during a median of 8.5 months (3-12 months). Eight patients had some degree of fibrosis (1 patient presented with F1, three patients F2, 2 patients F3, and 2 patients F4). The median pre-treatment viral load was 6.2 Log [5.9-6.8] with the HCV RNA becoming negative six weeks after starting the treatment in 100% of the patients. All patients maintained a sustained viral response at 12 weeks. Three patients (33.3%) had some type of adverse effect (2 headache and one oral thrush). The median post-treatment follow-up was 24 weeks (12-104). CONCLUSIONS: Treatment with ledipasvir/sofosbuvir in paediatric patients with chronic HCV infection genotype 1 and 4 is safe and effective with SVR12 and similar to those reported in adults.


Assuntos
Antivirais/administração & dosagem , Benzimidazóis/administração & dosagem , Fluorenos/administração & dosagem , Hepacivirus/isolamento & purificação , Hepatite C Crônica/tratamento farmacológico , Uridina Monofosfato/análogos & derivados , Adolescente , Antivirais/efeitos adversos , Benzimidazóis/efeitos adversos , Criança , Quimioterapia Combinada , Feminino , Fluorenos/efeitos adversos , Seguimentos , Genótipo , Hepacivirus/genética , Hepatite C Crônica/virologia , Humanos , Interferons/administração & dosagem , Masculino , Estudos Prospectivos , Ribavirina/administração & dosagem , Resultado do Tratamento , Uridina Monofosfato/administração & dosagem , Uridina Monofosfato/efeitos adversos , Carga Viral/efeitos dos fármacos
5.
Liver Transpl ; 24(12): 1736-1745, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30242960

RESUMO

Despite optimal medical treatment and strict low-protein diet, the prognosis of propionic acidemia (PA) patients is generally poor. We aim to report our experience with liver transplantation (LT) in the management of PA patients. Six patients with PA received a LT at a mean age of 5.2 years (1.3-7.5 years). The indications for LT were frequent metabolic decompensations in the first 4 patients and preventative in the last 2 patients. Two patients presented hepatic artery thromboses that were solved through an interventional radiologist approach. These patients showed a very high procoagulant state that was observed by thromboelastography. Arterial vasospasm without thrombus was observed in 2 patients during the LT surgery. In order to avoid hepatic artery thrombosis, an arterial conduit from the recipient aorta to the hepatic artery of the donor was used in the fifth patient. After LT, patients presented improvement in propionyl byproducts without complete normalization, but no decompensations have been observed. In conclusion, LT could be a good therapeutic option to improve the metabolic control and the quality of life of PA patients. Improved surgical strategies along with new techniques of interventional radiology allow us to perform the LT minimizing the complications derived from the higher risk of hepatic artery thrombosis.


Assuntos
Artéria Hepática/patologia , Transplante de Fígado/efeitos adversos , Complicações Pós-Operatórias/epidemiologia , Acidemia Propiônica/cirurgia , Trombose/epidemiologia , Aloenxertos/irrigação sanguínea , Aloenxertos/cirurgia , Anastomose Cirúrgica/métodos , Aorta/cirurgia , Criança , Pré-Escolar , Feminino , Artéria Hepática/cirurgia , Humanos , Lactente , Fígado/irrigação sanguínea , Fígado/cirurgia , Masculino , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/terapia , Estudos Prospectivos , Qualidade de Vida , Radiografia Intervencionista , Estudos Retrospectivos , Trombose/etiologia , Trombose/terapia , Resultado do Tratamento
7.
J Vasc Interv Radiol ; 29(6): 899-904, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29798761

RESUMO

This brief report presents the results of 20 adult and pediatric patients treated with the use of biodegradable SX-Ella biliary stents placed by means of a transhepatic approach for the treatment of benign biliary strictures after liver transplantation. Stent insertions were always feasible (100%), and only 1 case of acute pancreatitis was observed (5%). The overall clinical success rate of the procedure, including anastomotic and nonanastomotic strictures, was 75%, and was higher in the anastomotic stricture group (81.25%) than in the nonanastomotic stricture group (50%).


Assuntos
Colestase/terapia , Transplante de Fígado , Complicações Pós-Operatórias/terapia , Stents , Idoso , Materiais Biocompatíveis , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento
8.
Transpl Int ; 31(1): 38-44, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28833714

RESUMO

To assess the safety and efficacy of conversion from twice-daily tacrolimus to once-daily tacrolimus in pediatric liver transplant recipients. Conversion from twice-daily to once-daily tacrolimus was made in stable pediatric liver transplant recipients. Doses and serum levels of tacrolimus, liver, and renal function were recorded on the day before the conversion and at days 5, 30, 90, and 180 postconversion. Patients were controlled every 2-3 months thereafter. Fifty-five patients were enrolled in the study. The mean age at conversion was 10.2 ± 3.6 years. The mean tacrolimus trough level was 4.7 ± 1.9 ng/dl preconversion, followed by a significant decline to 4.2 ± 1.7 30 days after the switch (P < 0.004). Mean daily tacrolimus dose was 0.09 ± 0.046 mg/Kg preconversion with a significant increase to 0.11 ± 0.060 3 months postconversion (P < 0.001). Fifteen patients with calculated glomerular filtration rate between 60 to 80 ml/min/m2 preconversion showed a significant improvement one and 3 years after the switch (73 ± 4.1, 83 ± 4.3 and 90.3 ± 7.3 ml/min/m2 , respectively (P < 0.001). The mean follow-up was 5.2 ± 2.4 years. Conversion to once-daily tacrolimus is safe and effective in a cohort of stable pediatric liver transplant patients.


Assuntos
Imunossupressores/administração & dosagem , Transplante de Fígado , Tacrolimo/administração & dosagem , Adolescente , Criança , Pré-Escolar , Feminino , Rejeição de Enxerto/prevenção & controle , Humanos , Imunossupressores/farmacocinética , Lactente , Testes de Função Renal , Testes de Função Hepática , Masculino , Adesão à Medicação/estatística & dados numéricos , Estudos Prospectivos , Tacrolimo/farmacocinética
9.
Case Rep Infect Dis ; 2017: 4545721, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28326209

RESUMO

Primary meningococcal meningitis is an infrequent but known disease. However, the infection of a prosthetic joint with Neisseria meningitidis is rare. We hereby describe the second case of an arthroplasty infected with Neisseria meningitidis that responded favourably to prosthesis retention with surgical debridement, in combination with antibiotics treatment.

10.
Duazary ; 13(2): 87-94, 2016. tab
Artigo em Espanhol | LILACS, COLNAL | ID: biblio-988089

RESUMO

Se evaluó el recuento plaquetario en sangre periférica de sujetos sanos tratados con antiagregantes plaquetarios. Se analizaron 20 sujetos. Se distribuyeron en dos grupos: A: 10 sujetos que recibieron Aspirina (100 mg) y B: 10 con Clopidogrel (75 mg) por 7 días. Se les realizó recuento plaquetario en sangre periférica y en PRP. Encontrándose un conteo de plaquetas antes del tratamiento con antiagregantes en sangre periférica de 258,6 ± 54,46 x 109 l 7 días después de 254 ± 41,86 x 109 l (Aspirina), 285,4±70,92 y 196,5±37,90 x 109 l (Clopidogrel) respectivamente. En el PRP de los sujetos antes de recibir Aspirina fue 486,5 ± 129,54 x 109 l y después 449,2 ± 85,51 x 109 l; antes de la ingestión de Clopidogrel fue 565,2 ± 150,41 y 592,9 ± 203,46 x 109 l después del tratamiento. Se encontraron diferencias significativas solo para el conteo plaquetario en el grupo del Clopidogrel (p< 0.05). Se observó una disminución significativa del conteo plaquetario en sangre periférica posterior a la administración del Clopidogrel, posiblemente como consecuencia del mecanismo farmacológico del mismo. Son necesarios más estudios para evaluar un mayor número de individuos y medir mejor el efecto de los antiplaquetarios.


Platelet count in peripheral blood of healthy subjects with antiplatelet drugs. 20 subjects were analized. They were distributed in two groups: subject A: 10 who received aspirin (100 mg) and B:10 with Clopidogrel (75 mg) for 7 days. In all subjects studied platelet count in peripheral blood and PRP. It found a platelet count before treatment with antiplatelet agents in peripheral blood of 258,6 ± 54,46 x 109 l and 7 days after 254 ± 41,86 x 109 l (aspirin) and 285,4 ± 70, 196,5 ± 37,90 x 109 l (Clopidogrel) respectively. In the PRP of subjects before receiving aspirin was 486,5 ± 129,54 x 109 l and after 449,2 ± 85,51 x 109 l; prior to Clopidogrel ingestion was 565,2 ± 150,41 and 592,9 ± 203,46 x 109 l after treatment. Significant differences were found only for the platelet count in the Clopidogrel Group (p < 0.05). A significant decrease in platelet count was observed in peripheral blood after administration of Clopidogrel, possibly as a result of its pharmacological mechanism. More studies are needed to assess a greater number of individuals and better measure the effect of antiplatelet agents.


Assuntos
Plaquetas , Inibidores da Agregação de Plaquetas
11.
Schizophr Res ; 166(1-3): 207-11, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26032569

RESUMO

BACKGROUND: Constipation occurs in 25-60% of the subjects during administration of the antipsychotic drug (AP) clozapine (CLZ). METHODS: We used a colonic transit diagnostic test that quantifies in a single abdominal X-ray the number of silver O-ring markers out of 25 units ingested five days before. The quantity of markers is directly proportional to the degree of gastrointestinal hypomotility, and elimination of over 80% of the markers is considered normal. The test was applied to three groups of AP-treated subjects for at least three consecutive months: CLZ alone (n=45), CLZ+Other APs (n=28), and Other APs (n=64). RESULTS: The number of remaining markers at day 5 (mean±S.D.) was significantly higher in the CLZ alone (10.8±10.6) and in the CLZ+Other APs (9.7±9.7) groups than in the Other AP group (4.5±6.7), Kruskal-Wallis test: p=0.004. No significant associations were found between the number of markers, age, AP dose and treatment duration. All subjects who passed <80% of markers - which approximately corresponds to the 60th percentile of marker elimination - showed a scattered marker distribution along the colon, thus suggesting colon inertia. In subjects with hypomotility, 38.5% of the CLZ group, 25% of the CLZ+Other APs group, and 25% of the Other APs group were negative for the Rome III clinical criteria of constipation, thus showing objective, not subjective, hypomotility. CONCLUSIONS: This study objectively confirms significant gastrointestinal hypomotility associated with CLZ administration.


Assuntos
Antipsicóticos/efeitos adversos , Clozapina/efeitos adversos , Técnicas de Diagnóstico do Sistema Digestório , Trato Gastrointestinal/efeitos dos fármacos , Trato Gastrointestinal/diagnóstico por imagem , Radiografia Abdominal , Adulto , Antipsicóticos/uso terapêutico , Transtorno Bipolar/diagnóstico por imagem , Transtorno Bipolar/tratamento farmacológico , Transtorno Bipolar/fisiopatologia , Clozapina/uso terapêutico , Constipação Intestinal/induzido quimicamente , Constipação Intestinal/diagnóstico por imagem , Constipação Intestinal/fisiopatologia , Feminino , Trato Gastrointestinal/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Radiografia Abdominal/métodos , Esquizofrenia/diagnóstico por imagem , Esquizofrenia/tratamento farmacológico , Esquizofrenia/fisiopatologia , Compostos de Prata
14.
Pediatr Transplant ; 18(2): 185-9, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24438318

RESUMO

eHAT after LT remains a life-threatening complication. In the majority of anticoagulation protocols, heparin is used to prevent thromboses. Our study aimed to monitor AT-III levels in the early post-LT period to assess the need for the administration of AT-III concentrate to ensure the effectiveness of heparin. We monitored coagulation daily by measuring INR, APTT, fibrinogen, platelets, and AT-III. Anticoagulation therapy consisted of LMWH, AT-III, and dipyridamole. AT-III concentrate was administered when AT-III activity was ≤60%. DUS was performed daily for the first five post-operative days or whenever vascular thrombosis was suspected. Between October 2007 and October 2011, 39 LT were performed in our center. The median age was 26 months (6-196) with a median weight of 9 kg (5.5-49). AT-III activity was ≤60% in 27 patients. Lower levels were particularly observed in partial grafts and recipients weighing less than 10 kg. Patent arterial flow was present in all 39 LT during the first five post-operative days. AT-III levels were low in 70% of pediatric patients following LT, thereby risking heparin ineffectiveness. These results may implicate low AT-III levels in the etiology of eHAT post-LT. However, this is a small single-center pilot study and further larger prospective trials are required to confirm these results.


Assuntos
Antitrombina III/análise , Heparina/uso terapêutico , Falência Hepática/cirurgia , Transplante de Fígado , Adolescente , Anastomose Cirúrgica/métodos , Anticoagulantes/uso terapêutico , Criança , Pré-Escolar , Feminino , Artéria Hepática/patologia , Humanos , Imunossupressores/uso terapêutico , Lactente , Falência Hepática/sangue , Masculino , Projetos Piloto , Período Pós-Operatório , Trombose/patologia
15.
Opt Express ; 22(26): 32308-28, 2014 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-25607196

RESUMO

The effect of cross-regional or cross-cultural differences on color appearance ratings and memory colors of familiar objects was investigated in seven different countries/regions - Belgium, Hungary, Brazil, Colombia, Taiwan, China and Iran. In each region the familiar objects were presented on a calibrated monitor in over 100 different colors to a test panel of observers that were asked to rate the similarity of the presented object color with respect to what they thought the object looks like in reality (memory color). For each object and region the mean observer ratings were modeled by a bivariate Gaussian function. A statistical analysis showed significant (p < 0.001) differences between the region average observers and the global average observer obtained by pooling the data from all regions. However, the effect size of geographical region or culture was found to be small. In fact, the differences between the region average observers and the global average observer were found to of the same magnitude or smaller than the typical within region inter-observer variability. Thus, although statistical differences in color appearance ratings and memory between regions were found, regional impact is not likely to be of practical importance.


Assuntos
Visão de Cores/fisiologia , Comparação Transcultural , Rememoração Mental/fisiologia , Modelos Estatísticos , Análise e Desempenho de Tarefas , Adulto , Simulação por Computador , Feminino , Humanos , Internacionalidade , Masculino , Variações Dependentes do Observador
16.
Opt Express ; 22 Suppl 7: A1659-68, 2014 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-25607479

RESUMO

We present in this work a calculation of the theoretical limits attainable for natural light emulation with regard to the joint optimization of the Luminous Efficacy of Radiation and color fidelity by using multiple reflectance spectra datasets, along with an implementation of a physical device that approaches these limits. A reduced visible spectrum of blackbody radiators is introduced and demonstrated which allows lamps designed to emulate natural light to operate with excellent color fidelity and higher efficiency as compared to full visible spectrum sources. It is shown that even though 3,000K and 5,500K blackbody sources have maximum efficacies of 21 lm/W and 89 lm/W, respectively, reduced-spectrum artificial light sources can exceed those values up to 363 lm/W and 313 lm/W, respectively, while retaining excellent color fidelity. Experimental demonstration approaching these values is accomplished through the design and implementation of a 12-channel light engine which emits arbitrarily-tunable spectra. The color fidelity of the designed spectra is assessed through Color Rendering Maps, showing that color fidelity is preserved uniformly over a large spectral reflectance dataset, unlike other approaches to generate white light.

17.
Liver Int ; 34(5): 689-94, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24112412

RESUMO

BACKGROUND & AIMS: Pediatric acute liver failure is a rare disorder which results in death or the need for liver transplantation in 25-50% of cases. The adults scores are unable to predict survival without liver transplantation of pediatric patients. The present study assessed the use the of indocyanine green plasma disappearance rate as a tool to predict the evolution of pediatric patients with acute liver failure. PATIENTS AND METHODS: All patients met the criteria of acute liver failure according to the Pediatric Acute Liver Failure Study Group. King's College, Clichy's criteria and ICG-PDR were obtained on admission or when acute liver failure was diagnosed and repeated every 12-24 hours, respectively. RESULTS: Thirteen out of 48 patients suffered an irreversible liver damage. Seven of them underwent a liver transplantation and 6 died on the waiting. A total of 154 ICG-PDR measurements were taken during the study (Median 12.4 %/min, r:6.2 - 26.3). The ICG-PDR was significantly lower in patients who suffered irreversible liver damage compared with those who survived without liver transplantation (median ICG-PDR 4.1 %/min; r:4.0 - 5.7 vs median ICG-PDR 20.3 %/min; r: 9.1 - 30.1; respectively. P < 0.001). Using a ROC curve the cutoff of ICG-PDR for assessing the need for liver transplantation was set at 5.9 %/min (sensitivity 92.3%, specificity 97.1%). Sensitivity, specificity, PPV, NPV and DA for ICG-PDR were higher than the King's College and Clichy's criteria. CONCLUSIONS: ICG-PDR is a powerful tool that would improve the categorization of patients with pediatric acute liver failure.


Assuntos
Corantes , Verde de Indocianina , Falência Hepática Aguda/diagnóstico , Criança , Pré-Escolar , Corantes/metabolismo , Feminino , Humanos , Verde de Indocianina/metabolismo , Lactente , Falência Hepática Aguda/sangue , Masculino , Valor Preditivo dos Testes , Estudos Prospectivos , Estudos Retrospectivos
18.
Opt Lett ; 37(23): 4997-9, 2012 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-23202116

RESUMO

In this Letter, the main attributes known to affect color quality are treated statistically over a set of 118 spectra representing the current mainstream lighting technology. The color rendering index (CRI) is used to assess color fidelity while colorfulness is used to complement CRI-R(a), supported by the growing evidence that assessment of light spectra cannot overlook color preference inputs. Colorfulness is evaluated by our optimal color (O(c)) index, through a code that computes the (MacAdam) theoretical maximum volumetric gamut of objects under a given illuminant for all the spectra in our database. Pearson correlation coefficients for CRI-R(a), the (Y. Ohno's) color quality scale (CQS) and O(c) show a high correlation (0.950) between CRI-R(a) and CQS-Q(a), while O(c) shows the lowest correlation (0.577) with CRI-R(a), meaning that O(c) represents the best complement to CRI-R(a) and Q(a) for an in-depth study of color quality.

19.
Opt Express ; 20(5): 4939-56, 2012 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-22418299

RESUMO

The method of evaluating color rendering using a visual, graphical metric is presented. A two-dimensional Color Rendering Map (CRM) of a light source's color-rendering capabilities is explained and demonstrated. Extension of this technique to three-dimensional CRMs of objects under illumination is explained, including the method of introducing numerical indices in order to evaluate standards for specific applications in lighting. Three diverse applications, having a range from subtle to significant color variation, are shown with their respective CRMs. These three applications are also used to demonstrate how three differing light sources produce different maps. The results show a flexible, simple method to obtain a clear, visual determination of color rendering performance from differing sources used in differing illumination applications. The use of numeric indices in these applications shows how specific standards can be imposed in assessing the applicability of a light source.


Assuntos
Algoritmos , Cor , Colorimetria/instrumentação , Gráficos por Computador , Iluminação/instrumentação , Desenho de Equipamento , Análise de Falha de Equipamento/instrumentação , Análise de Falha de Equipamento/métodos
20.
Liver Transpl ; 17(12): 1474-80, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21932378

RESUMO

The outcomes and characterization of hepatitis C virus (HCV) infections after pediatric liver transplantation (LT) have rarely been reported. We describe our experience with HCV infections after pediatric LT. Ten of 207 children (4.8%) who underwent LT at our institution (1985-2010) developed previously undiagnosed HCV disease. Eight received a liver graft before blood product and donor screening for HCV became available. The mean age at transplantation was 8.9 ± 4.3 years, and the median time from transplantation to the diagnosis of HCV was 15.1 years (range = 0.2-19.7 years). The genotypes were 1 (n = 8), 3 (n = 1), and undetermined (n = 1). At the time of this writing, all the patients were still alive with a mean follow-up of 7.3 ± 5.5 years after the diagnosis of HCV. Five patients did not receive treatment; 2 of these patients achieved spontaneous viral clearance (SVC). Four of the 5 treated patients achieved a sustained virological response, and 3 had an early virological response (EVR). Two of these 4 patients developed chronic rejection while they were on treatment, but this was resolved with a conversion from cyclosporine A to tacrolimus. The remaining patient was continuing treatment and had achieved EVR. In conclusion, despite the limitations of our series, de novo HCV infections after pediatric LT seem to have a slow histological progression. Even with genotype 1, the patients have a good long-term prognosis and respond well to treatment. Nevertheless, chronic rejection during antiviral therapy may develop. In addition, SVC may occur in this population.


Assuntos
Hepatite C/etiologia , Transplante de Fígado/efeitos adversos , Adolescente , Antivirais/uso terapêutico , Biomarcadores/sangue , Criança , Pré-Escolar , Doença Crônica , Feminino , Rejeição de Enxerto/etiologia , Rejeição de Enxerto/prevenção & controle , Hepacivirus/genética , Hepacivirus/imunologia , Hepatite C/diagnóstico , Hepatite C/tratamento farmacológico , Hepatite C/patologia , Anticorpos Anti-Hepatite C/sangue , Humanos , Imunossupressores/efeitos adversos , Masculino , RNA Viral/sangue , Espanha , Fatores de Tempo , Resultado do Tratamento , Carga Viral
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