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1.
Clin Gastroenterol Hepatol ; 20(12): 2905-2907.e2, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-34555518

RESUMO

Eosinophilic esophagitis (EoE) is an immune-mediated condition characterized by symptoms of esophageal dysfunction and an eosinophilic inflammation of the esophagus.1 Swallowed topical steroids represent one of the possible strategies for inducing and maintaining remission in EoE.2 To date, a validated maintenance strategy has yet to be defined, especially in children. The available evidence suggests decreasing the dose after a successful induction therapy.3 No study has reported the efficacy of a continuous progressive dose reduction; thus, it is unknown if all patients need to use the same dosages and for how long.4,5.


Assuntos
Esofagite Eosinofílica , Criança , Humanos , Esofagite Eosinofílica/diagnóstico , Budesonida , Glucocorticoides/uso terapêutico , Esteroides/uso terapêutico
2.
J Pediatr Gastroenterol Nutr ; 75(3): 325-333, 2022 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-35706095

RESUMO

OBJECTIVES: Few pediatric data on phenotypic aspects of eosinophilic esophagitis (EoE) are available. The pEEr registry was developed to prospectively characterize children with EoE from Europe and Israel. METHODS: pEEr is an ongoing prospective registry enrolling children with esophageal eosinophilia (≥15 eos/HPF). Anonymized data were collected from 19 pediatric centers. Data regarding demographics, clinical manifestations, endoscopy, histology, and therapies were collected. RESULTS: A total of 582 subjects (61% male) were analyzed. The median age at diagnosis was 10.5 years [interquartile range (IQR): 5.7-17.7], whereas the age at symptom onset was 9.2 years (IQR: 4.3-16.4), resulting in a median diagnostic delay of 1.2 years (IQR: 0.7-2.3). The diagnostic delay was longer below age <6 years. Shorter diagnostic delays were associated with the presence of food allergy or a family history for EoE. Symptoms varied by age with dysphagia and food impaction more common in adolescents, while vomiting and failure to thrive more common in younger children ( P < 0.001). Among endoscopic findings, esophageal rings were more common in adolescents, whereas exudates were more frequent in younger children( P < 0.001). Patients who responded to proton pump inhibitors (PPIs) were more likely to be older, males, and less often presented severe endoscopic findings. Patients unresponsive to PPIs received topical steroids (40%), elimination diet (41%), or a combined therapy (19%). CONCLUSIONS: EoE findings vary according to age in pediatric EoE. Young children are commonly characterized by non-specific symptoms, atopic dermatitis, food allergy, and inflammatory endoscopic lesions. Adolescents usually have dysphagia or food impaction, fibrostenotic lesions, and a better PPI response.


Assuntos
Transtornos de Deglutição , Esofagite Eosinofílica , Hipersensibilidade Alimentar , Adolescente , Criança , Pré-Escolar , Transtornos de Deglutição/tratamento farmacológico , Transtornos de Deglutição/etiologia , Diagnóstico Tardio , Endoscopia Gastrointestinal , Enterite , Eosinofilia , Esofagite Eosinofílica/complicações , Esofagite Eosinofílica/diagnóstico , Esofagite Eosinofílica/epidemiologia , Feminino , Gastrite , Humanos , Masculino , Inibidores da Bomba de Prótons/uso terapêutico , Sistema de Registros
3.
Pediatr Dev Pathol ; 25(2): 99-106, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34492208

RESUMO

BACKGROUND: Accurate measurements of mucosal eosinophil concentrations in gastrointestinal tracts of healthy children are necessary to differentiate health and disease states in general, and better define eosinophilic gastrointestinal diseases. STUDY: We retrospectively reviewed gastrointestinal biopsies from children with macroscopically normal endoscopies, who, after a minimal follow-up of one year, were not diagnosed with any organic disease. Peak eosinophil concentrations and distributions were assessed from each segment of the gastrointestinal tract. RESULTS: Three centers (Italy, United Kingdom, and Israel) contributed 202 patients (median age 13 years IQR 9.5-15.5, range 1-18 years). Median (IQR, range) eosinophil concentrations (eos/mm2) were: esophagus 0 (0-0, 0-84), stomach 0 (0-4, 0-84), duodenal bulb 20 (13-30, 7-67), second part of duodenum 20 (13-29, 0-105), terminal ileum 29 (14-51, 0-247), cecum 53 (37-89, 10-232), ascending colon 55 (25-84, 0-236), transverse colon 38 (21-67, 4-181), descending colon 29 (17-59, 0-114), sigmoid colon 25 (13-40, 0-215) and rectum 13 (4-28, 0-152). Significant geographical variance was present, however, no differences in eosinophil concentrations were identified between children with resolving symptoms vs. those with functional diagnoses, nor across age groups. CONCLUSIONS: Standardized eosinophil concentrations from the gastrointestinal tracts of children without organic disease will serve to better define both health and disease states. No differences were found between resolved symptoms vs. functional diagnoses nor between age groups in this pediatric cohort.


Assuntos
Eosinofilia , Gastrite , Adolescente , Criança , Pré-Escolar , Eosinofilia/patologia , Eosinófilos/patologia , Gastrite/patologia , Humanos , Lactente , Estudos Retrospectivos
4.
J Pediatr Gastroenterol Nutr ; 72(5): 736-741, 2021 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-33416268

RESUMO

OBJECTIVES: Retrospective, observational, single-center, cohort study investigating the safety profile of biological therapy in children with inflammatory bowel disease (IBD). METHODS: Retrospective, observational, cohort study of pediatric patients with IBD, receiving infliximab, adalimumab, vedolizumab, or ustekinumab for at least 2 months. Data related to the immediate and delayed adverse events (AEs) were collected, focusing on the reaction type and severity, the time of onset, the outcome and the temporary or definitive therapy discontinuation secondary to the AE. Number of suspected and confirmed coronavirus disease-209 (COVID-19) cases and their outcomes, as well as flu vaccination coverage were collected. RESULTS: One hundred eighty-five children were included (101 [55%] CD, 82 [44%] UC, and 2 [1%] IBDU): 149 received infliximab (IFX) (81%), 88 (48%) adalimumab (ADA), 18 (21%) vedolizumab, and 4 (2%) ustekinumab. The overall AE rates were 49%, 67% of whom likely medication-related. Eleven (6%) patients experienced more than 1 AE, 18 patients (10%) presented an immediate reaction, and 82 (45%) a delayed AE. Among the 90 patients experiencing at least 1 AE, 97% had mild-to-moderate AEs. Only 4 SAEs were reported (4%). Treatment discontinuation because of AE occurred in 25 patients (14%). Four COVID-19 cases were reported, all with a mild course. CONCLUSIONS: Our findings confirm a good safety profile of biologics. Infusion reactions to IFX administration remain one of the main issues, significantly linked to its immunogenicity and consequently with an impact on its efficacy and durability.


Assuntos
COVID-19 , Doenças Inflamatórias Intestinais , Adalimumab/efeitos adversos , Terapia Biológica/efeitos adversos , Criança , Estudos de Coortes , Humanos , Doenças Inflamatórias Intestinais/tratamento farmacológico , Infliximab/efeitos adversos , Estudos Retrospectivos , SARS-CoV-2 , Resultado do Tratamento
5.
Dig Dis Sci ; 64(6): 1571-1578, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30659470

RESUMO

BACKGROUND: A new prepared oral viscous budesonide (PVB) has been effective in inducing clinical and histological remission in pediatric eosinophilic esophagitis (EoE). AIMS: To evaluate the efficacy of a 12-week maintenance therapy on clinical, endoscopic, and histological remission using half of the dose used in the induction therapy. METHODS: We prospectively enrolled pediatric patients with active EoE. After 12 weeks of induction therapy with PVB (< 150 cm: 2 mg/day; ≥ 150 cm: 4 mg/day) patients received a maintenance dose of half of the dose used in the induction therapy (1 mg or 2 mg) for another 12 weeks. A 12-week follow-up was then performed in all patients after the end of therapy. Endoscopy was performed at weeks 0, 12, 24, and 36. Symptoms, endoscopy, and histology scores were also calculated. Serum cortisol was evaluated during the treatment period. RESULTS: We enrolled 20 children (15 males; median age 10 years; range 4-17). After the 12-week induction therapy 18 patients (90%) were in remission, with a significant decrease in the median peak of eosinophil count/HPF as well as a marked reduction in clinical, endoscopic, and histological scores (p < 0.01). At the end of the maintenance therapy (week 24), 17 patients (85%) were still in remission, while there were only 9 at week 36 (45%). No significant changes in cortisol levels were observed during the study period. CONCLUSIONS: The 12-week maintenance treatment with the half the dose of PVB was effective in sustaining remission at week 24; however, no reduction in the rate of relapse after suspension of treatment occurred.


Assuntos
Budesonida/administração & dosagem , Esofagite Eosinofílica/tratamento farmacológico , Glucocorticoides/administração & dosagem , Administração Oral , Adolescente , Idade de Início , Budesonida/efeitos adversos , Criança , Pré-Escolar , Esquema de Medicação , Composição de Medicamentos , Esofagite Eosinofílica/imunologia , Esofagite Eosinofílica/patologia , Feminino , Glucocorticoides/efeitos adversos , Humanos , Quimioterapia de Manutenção , Masculino , Soluções Farmacêuticas , Projetos Piloto , Estudos Prospectivos , Recidiva , Indução de Remissão , Cidade de Roma , Fatores de Tempo , Resultado do Tratamento , Viscosidade
6.
J Pediatr Gastroenterol Nutr ; 64(2): 218-224, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27253660

RESUMO

OBJECTIVES: Oral viscous budesonide is a recent therapeutic option for eosinophilic oesophagitis (EoE) compared with dietary restriction and inhaled steroids. This single-centre, open-label, not blinded study aims to evaluate the efficacy and safety of a new, preprepared oral viscous budesonide suspension (PVB) in children and adolescents with EoE. METHODS: We treated 36 children with PVB (29 boys; median age 12 years) with EoE diagnosed according to European Society for Paediatric Gastroenterology Hepatology and Nutrition guidelines. Patients <150 and >150 cm height received 2 and 4 mg PVB daily, respectively, for 12 weeks. Upper gastrointestinal endoscopy was performed at baseline, after 12 weeks of therapy and 24 weeks after the end of therapy. Baseline and post-treatment scores were calculated for symptoms, endoscopy, and histology. Serum cortisol was performed at baseline, 12, and 36 weeks. RESULTS: At the end of PVB trial, endoscopy showed macroscopic remission in 32 patients (88.9%), whereas at histology median pre- and post-treatment peak eosinophil count/high power field (HPF) markedly decreased from 42.2 (range: 15-100) to 2.9 (range: 0-30); moreover, mean symptom and histology scores impressively improved compared with baseline (P < 0.01). At 24 weeks after the end of PVB therapy, endoscopy showed oesophageal relapse in 21 patients (58.3%), whereas 15 (41.7%) were still in remission. Seven children (19.4%) with positive multichannel intraluminal impedance-pH were treated also with proton pump inhibitors. No significant difference between pre-/post-treatment morning cortisol levels occurred. CONCLUSIONS: The new PVB suspension presented in the present study is effective and safe for treating children with proven EoE. Larger placebo-controlled clinical trials would provide more information about dosing, efficacy, and long-term safety of this formulation, specifically designed for the oesophagus.


Assuntos
Anti-Inflamatórios/administração & dosagem , Budesonida/administração & dosagem , Esofagite Eosinofílica/tratamento farmacológico , Administração Oral , Adolescente , Anti-Inflamatórios/uso terapêutico , Budesonida/uso terapêutico , Criança , Pré-Escolar , Esofagite Eosinofílica/diagnóstico , Feminino , Seguimentos , Humanos , Masculino , Projetos Piloto , Estudos Prospectivos , Suspensões , Resultado do Tratamento
7.
Pediatr Allergy Immunol ; 26(1): 18-24, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25684674

RESUMO

BACKGROUND: Lymphoid nodular hyperplasia (LNH) of the lower gastrointestinal tract is a common finding during paediatric colonoscopies, and its clinical significance has not yet been clearly established. OBJECTIVE: The purpose of this prospective, parallel multi-arm, randomized clinical trial was to study relationship between food allergy and LNH. METHODS: We recruited 268 children who had undergone a diagnostic colonoscopy between 1 January 2009 and 30 September 2011. The inclusion criteria were the following: (i) demonstration of LNH; (ii) no concomitant inflammatory or immune disease; (iii) no treatment since the clinical onset. The patients were assigned 1:1:1 to elimination diet (Group A), mesalamine (Group B) or symptomatic treatment with antispasmodics or antidiarrhoeal drugs (Group C) for an 8-wk period. Patients were followed for 24 months. RESULTS: We enrolled 72 of 97 children with intestinal LNH who were referred for haematochezia (76%), recurrent abdominal pain (68%) and/or chronic diarrhoea (32%). Clinical improvement was observed in 75%, 83% and 79% of the patients in Groups A, B and C, respectively. The difference in the response to treatment among the groups and the association to the clinical, endoscopic and allergic features of the patients were not statistically significant. CONCLUSIONS: Intestinal LNH should be considered a benign finding in children without red flags, because the symptoms are largely self-limiting. The use of mesalamine or elimination diet does not modify the clinical outcome compared to symptomatic therapy. The presence of food allergy was not predicted by allergy skin testing and was found in a minority of patients.


Assuntos
Hiperplasia do Linfonodo Gigante/epidemiologia , Hipersensibilidade Alimentar/epidemiologia , Mesalamina/administração & dosagem , Adolescente , Anti-Inflamatórios não Esteroides/administração & dosagem , Anti-Inflamatórios não Esteroides/efeitos adversos , Antidiarreicos/administração & dosagem , Antidiarreicos/efeitos adversos , Hiperplasia do Linfonodo Gigante/terapia , Criança , Pré-Escolar , Colonoscopia , Dietoterapia , Feminino , Seguimentos , Hipersensibilidade Alimentar/terapia , Humanos , Itália , Masculino , Mesalamina/efeitos adversos , Parassimpatolíticos/administração & dosagem , Parassimpatolíticos/efeitos adversos , Estudos Prospectivos , Testes Cutâneos
8.
Inflamm Bowel Dis ; 29(7): 1057-1064, 2023 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-35942651

RESUMO

BACKGROUND: Scarce data have investigated the association between pediatric inflammatory bowel disease (IBD) and eosinophilic esophagitis (EoE). We, therefore, aimed to describe the epidemiology and the possible peculiar phenotype and natural history of such an association. METHODS: Case-control study is based on the Italian Society for Pediatric Gastroenterology (SIGENP) national registry. All children with a combined diagnosis of IBD and EoE were included. The overall prevalence and incidence in 2 periods, 2009 to 2015, and 2016 to 2021, were calculated. Cases were matched with IBD only and EoE only patients in a 1:3:3 ratio. Phenotype and outcomes (courses of steroids, risk of complications, surgery, treatment escalation, and hospitalization) were compared between groups. RESULTS: Eleven patients (age 11.2 ±â€…2.8 years, Males 91%) with EoE-IBD out of 3090 patients with IBD were identified, resulting in an overall prevalence of 0.35% and an incidence of 0.18% for 2009 to 2015 and 0.45% for 2016 to 2021. Treatment escalation rates for IBD were significantly higher in patients with IBD compared with EoE-IBD at 12- and 24-month follow-up (0% vs 30%, P = .04; and 9% vs 45.5%, P = .03, respectively). Furthermore, patients with IBD were at a significantly higher risk of hospitalization than both EoE-IBD and EoE patients (log rank P < .001). We found no significant differences in major outcomes related to the EoE course in EoE-IBD patients compared with EoE ones. CONCLUSIONS: The incidence and prevalence of EoE in children with IBD are low, although the incidence seems to be rising in recent years. Having EoE appears to be associated with a milder IBD disease course, whereas having IBD does not seem to affect the natural history of EoE. More data are needed to better define the phenotype of such association.


We investigated the association between pediatric inflammatory bowel disease (IBD) and eosinophilic esophagitis (EoE). Our results showed that having an EoE might be associated with a milder IBD disease course, but larger cohort analyses are needed to confirm such result.


Assuntos
Esofagite Eosinofílica , Doenças Inflamatórias Intestinais , Masculino , Humanos , Esofagite Eosinofílica/complicações , Esofagite Eosinofílica/epidemiologia , Estudos de Casos e Controles , Doenças Inflamatórias Intestinais/complicações , Doenças Inflamatórias Intestinais/epidemiologia
9.
Paediatr Drugs ; 22(4): 343-356, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32519266

RESUMO

Eosinophilic esophagitis (EoE) is a chronic immune-mediated inflammatory disorder characterized by symptomatic esophageal dysfunction and an eosinophil-predominant inflammation of the esophagus. EoE arises from interaction between genetic and environmental factors. In pediatric patients, clinical manifestations vary depending on age, from a gastroesophageal reflux disease (GERD)-like condition to severe dysphagic symptoms. Upper endoscopy is considered the gold standard for diagnosis and monitoring of EoE; however, significant efforts are underway to identify noninvasive diagnostic tools and biomarkers to avoid repetitive invasive procedures. Therapeutic first-line options currently available for EoE are elimination diets, proton pump inhibitors (PPIs), and steroids. The aim of treatment is to improve clinical symptoms while obtaining mucosal healing and avoiding long-term complications. Dietary treatment options comprise different empiric diets or an exclusively amino acid formula. Despite the efficacy of diets, compliance is often challenging. PPIs and topical steroids represent the main pharmacological options for EoE, and both can induce and maintain remission. Topical steroids have been reported as more effective, but data on long-term safety remain insufficient for both these and PPIs. Endoscopic dilations are currently reserved for severe untreated fibrostenotic disease unresponsive to medical therapies. Several biologic agents are available but not yet approved for EoE.


Assuntos
Esofagite Eosinofílica/tratamento farmacológico , Refluxo Gastroesofágico/tratamento farmacológico , Inibidores da Bomba de Prótons/uso terapêutico , Criança , Endoscopia , Glucocorticoides/uso terapêutico , Humanos , Cooperação do Paciente
10.
Dig Liver Dis ; 52(2): 158-163, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31653522

RESUMO

BACKGROUND: Topical steroids are effective in eosinophilic esophagitis (EoE), but patients often show different tendencies to relapse. We assessed whether gene expression is associated with a sort of steroid dependency in EoE children. METHODS: Biopsy samples were prospectively collected on EoE children responding to topical steroids. Patients treated with viscous budesonide for 24 weeks were subsequently classified as early (6 months) or late (>6 months) relapsing. RNA was isolated from esophageal biopsies at the time of the relapse and analyzed by NGS for transcriptome profiling. RESULTS: Of 40 patients, 22 patients were considered for mRNA expression profile. Thirteen were included in the early-relapse group, and 9 were in the late-relapse. No significant difference was observed in the two groups for clinical, endoscopic or histological features. Using the mRNA expression profile we performed supervised clustering using the 10 top differentially expressed genes between early and late relapsing patients. The heatmap and PCA show a proper segregation among patients. SERPINB12 is the only gene attaining a significant differential expression between the two groups (FDR < 0.05). CONCLUSIONS: Different tendencies to relapse in EoE children responding to topical steroids might be related to altered mRNA expressions. SERPINB12 presented a significantly higher expression in the late relapse group and it deserves further investigations.


Assuntos
Budesonida/administração & dosagem , Esofagite Eosinofílica/genética , Perfilação da Expressão Gênica , Serpinas/genética , Esteroides/administração & dosagem , Adolescente , Biomarcadores , Budesonida/efeitos adversos , Criança , Esofagite Eosinofílica/tratamento farmacológico , Esôfago/patologia , Feminino , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Projetos Piloto , RNA Mensageiro/genética , Recidiva , Esteroides/efeitos adversos
11.
World J Clin Cases ; 7(16): 2256-2268, 2019 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-31531320

RESUMO

BACKGROUND: Allergy to cow's milk is the most frequent allergy occurring in infants and young children. The dietary management of these patients consists of the elimination of any cow's milk proteins from the diet, and for formula-fed infants, the substitution of the usual infant formula with an adapted formula that is generally based on extensively hydrolyzed cow's milk proteins. The American Academy of Pediatrics has established specific criteria to confirm the hypoallergenicity of a formula intended for these children. AIM: To assess the hypoallergenicity of a new thickened extensively hydrolyzed casein-based formula (TeHCF) in children with cow's milk allergy (CMA). METHODS: Children diagnosed with CMA through a double-blind placebo-controlled food challenge (DBPCFC) were randomly administered increased doses of a placebo formula or the TeHCF [Allernova, new thickener including fibres (Novalac)] under double-blind conditions and medical surveillance on two separate days. Otherwise, both of these formulas and a cow's milk-based formula were randomly introduced to children who were highly suspected of having CMA on three separate days. Immediate and late reactions occurring after the introduction of any of these formulas were thoroughly recorded by the physician at the hospital and reported by parents to the physician after hospital discharge, respectively. If the children tolerated the TeHCF during the DBPCFC, they were exclusively fed this formula during a 3-mo period where potential allergic symptoms, anthropometric parameters, as secondary outcomes, and adverse events were registered. The Cow's Milk-related Symptoms Score (CoMiSSTM) was assessed and anthropometric parameters were compared to World Health Organization (WHO) reference data. RESULTS: Of the 30 children included in the study, the CMA diagnosis of 29 (mean age: 8.03 ± 7.43 mo) patients was confirmed by a DBPCFC. The children all tolerated the TeHCF during both the challenge and the subsequent 3-mo feeding period, which they all completed. During the latter period, the CoMiSSTM remained at a very low level, never exceeding its baseline value (1.4 ± 2.0), growth parameters were within WHO reference standards and no adverse event related to the TeHCF was reported. Over the first week of this period, the proportion of patients with digestive discomfort significantly decreased from 20.7% (6/29) to 3.4% (1/29), P = 0.025. The proportion of satisfaction with the overall effect of the formula reported by the parents and investigator was high, as was the formula acceptability by the child. CONCLUSION: The new TeHCF meets the hypoallergenicity criteria according to the American Academy of Pediatrics standards, confirming that the tested TeHCF is adapted to the dietary management of children with CMA. Moreover, growth was adequate in the included population.

12.
Dig Liver Dis ; 50(9): 910-915, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29724467

RESUMO

BACKGROUND: Gastro-oesophageal reflux is very common in the paediatric age group. There is no single and reliable test to distinguish between physiologic and pathological gastro-oesophageal reflux, and this lack of clear distinction between disease and normal can have a negative impact on the management of children. AIMS: To evaluate the usefulness of 24-h oesophageal pH-impedance study in infants and children with suspected gastro-oesophageal reflux disease. METHODS: Patients were classified by age groups (A-C) and reflux-related symptoms (typical and atypical). All underwent pH-impedance study. If the latter suggested an abnormal reflux, patients received therapy in accordance with NASPGHAN/ESPGHAN recommendations, while those with normal study had an additional diagnostic work-up. The efficacy of therapy was evaluated with a specific standardized questionnaire for different ages. RESULTS: The study was abnormal in 203/428 patients (47%) while normal in 225/428 (53%). Of those with abnormal study, 109 exhibited typical symptoms (54%), and 94 atypical (46%). The great majority of the patients with abnormal study were responsive to medical anti-reflux therapy. CONCLUSIONS: We confirm the utility of prolonged oesophageal pH-impedance study in detecting gastro-oesophageal reflux disease in children and in guiding therapy. Performing oesophageal pH-impedance monitoring in children with suspected gastro-oesophageal reflux disease is helpful to establish the diagnosis and avoid unnecessary therapy.


Assuntos
Impedância Elétrica , Monitoramento do pH Esofágico/métodos , Refluxo Gastroesofágico/diagnóstico , Adolescente , Análise de Variância , Criança , Pré-Escolar , Feminino , Refluxo Gastroesofágico/tratamento farmacológico , Humanos , Lactente , Masculino , Estudos Prospectivos , Inibidores da Bomba de Prótons/uso terapêutico , Inquéritos e Questionários
13.
PLoS One ; 11(1): e0147464, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26816029

RESUMO

This paper describes a computational approach to the theoretical problems involved in the Young's single-photon double-slit experiment, focusing on a simulation of this experiment in the absence of measuring devices. Specifically, the human visual system is used in place of a photomultiplier or similar apparatus. Beginning with the assumption that the human eye perceives light in the presence of very few photons, we measure human eye performance as a sensor in a double-slit one-photon-at-a-time experimental setup. To interpret the results, we implement a simulation algorithm and compare its results with those of human subjects under identical experimental conditions. In order to evaluate the perceptive parameters exactly, which vary depending on the light conditions and on the subject's sensitivity, we first review the existing literature on the biophysics of the human eye in the presence of a dim light source, and then use the known values of the experimental variables to set the parameters of the computational simulation. The results of the simulation and their comparison with the experiment involving human subjects are reported and discussed. It is found that, while the computer simulation indicates that the human eye has the capacity to detect the corpuscular nature of photons under these conditions, this was not observed in practice. The possible reasons for the difference between theoretical prediction and experimental results are discussed.


Assuntos
Simulação por Computador , Modelos Biológicos , Visão Ocular/fisiologia , Vias Visuais/fisiologia , Percepção Visual/fisiologia , Algoritmos , Humanos , Luz , Fótons
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