Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Resultados 1 - 9 de 9
Filtrar
1.
Rev Sci Instrum ; 92(9): 094103, 2021 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-34598543

RESUMEN

We describe the design, construction, operation, and performance of a simple and versatile semi-batch reactor that is especially useful for measurement of gas/solid reaction rates at pressures in the range of 1 mTorr to 1500 Torr. The reactor operates by repeatedly imposing small AC modulations of reactant gas pressure on top of a much larger DC pressure background. Based on the rate of pressure relaxation following each AC pulse, the reaction rate is determined. Our design is characterized by modular construction from off-the-shelf, ultra-high-vacuum-compatible components, which facilitate easy retrofitting and adaptation to a range of experimental conditions. Automated experiment control and data acquisition is accomplished via a custom National Instruments© LabView virtual instrument. Data analysis is automated using a custom series of Mathworks© Matlab scripts. We demonstrate reactor performance through measurements of hydrogenation kinetics for a composite H2 getter material consisting of 1,4-bis(phenylethynyl)benzene mixed with a palladium/carbon catalyst.

2.
J Crohns Colitis ; 15(3): 367-374, 2021 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-33022055

RESUMEN

BACKGROUND: The aim of this study was to define clusters of activity in a population-based cohort during the first 5 years after diagnosis in children with ulcerative colitis [UC] and to identify early prognostic risk factors. METHODS: All UC patients from the SIGENP IBD registry with a complete follow-up of at least 5 years were included. Active disease was defined every 6 months in the presence of at least one of the following: clinical activity [Paediatric Ulcerative Colitis Activity Index ≥ 35]; endoscopic activity [Mayo score ≥ 1]; faecal calprotectin > 250 µg/g; hospitalization; surgery; or treatment escalation. Formula-based clusters were generated based on four published questionnaire-based activity patterns in adults, plus one additional cluster. RESULTS: In total, 226 patients were identified. Forty-two [19%] had moderate-severe chronically active disease, 31 [14%] chronic-intermittent, 75 [33%] quiescent, 54 [24%] active disease in the first 2 years after the diagnosis, then sustained remission, and 24 [11%] a remission in the first 2 years then an active disease. Mild disease onset along with a lower clinical severity not requiring the use of corticosteroids at 6 months were related to a quiescent disease course at the next follow-up (logistic model area under the curve 0.86 [95% confidence interval 0.78-0.94]; positive predictive value 67%; negative predictive value 70%). Eight per cent of patients needed surgery, none in the quiescent group [p = 0.04]. CONCLUSIONS: More than one-third of children with UC present with a chronically active or intermittent course during the first 5 years of follow-up. A significant group of patients has active disease in the first 2 years and then sustained remission. Interestingly, after initial treatment, one-third of patients have well-controlled disease throughout.


Asunto(s)
Colitis Ulcerosa/epidemiología , Índice de Severidad de la Enfermedad , Adolescente , Niño , Colectomía/estadística & datos numéricos , Colitis Ulcerosa/terapia , Progresión de la Enfermedad , Utilización de Medicamentos/tendencias , Femenino , Estudios de Seguimiento , Glucocorticoides/uso terapéutico , Humanos , Italia/epidemiología , Masculino , Sistema de Registros , Inducción de Remisión
3.
Eur Rev Med Pharmacol Sci ; 13 Suppl 1: 23-32, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19530508

RESUMEN

Inflammatory bowel diseases (IBD) are often associated with extraintestinal manifestations (EIMs), which occur in approximately one third of patients. There is only few published data on the occurrence of these manifestations in children and adolescents, so most of the data are taken by studies in adult patients. The organs most commonly affected are joints, skin, eyes and biliary tract, although nearly every organ may be involved. Some of the EIMs are clearly related to intestinal disease activity (i.e., erythema nodosum, peripheral arthritis, orofacial lesions), whereas others occur independently (i.e., pyoderma gangrenosum, anterior uveitis/iritis, ankylosing spondylitis, primary sclerosing cholangitis). Many extraintestinal disorders may be direct inflammatory and metabolic complications of the intestinal inflammation (i.e., osteoporosis, growth retardation, nephrolithiasis, ureteral obstruction, thromboembolic disease). In this review we provide an overview on the prevalence and clinical aspects of the more commonly reported EIMs of Crohn's disease and ulcerative colitis in pediatric patients, focusing on specific issues of children affected by IBD (growth failure and metabolic osteopathy).


Asunto(s)
Enfermedades Inflamatorias del Intestino/diagnóstico , Adolescente , Enfermedades Óseas Metabólicas/diagnóstico , Niño , Colangitis Esclerosante/diagnóstico , Oftalmopatías/diagnóstico , Trastornos del Crecimiento/diagnóstico , Humanos , Enfermedades Musculoesqueléticas/diagnóstico , Enfermedades de la Piel/diagnóstico , Enfermedades Urológicas/diagnóstico
4.
Aliment Pharmacol Ther ; 48(5): 523-537, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-29984520

RESUMEN

BACKGROUND: Risk benefit strategies in managing inflammatory bowel diseases (IBD) are dependent upon understanding the risks of uncontrolled inflammation vs those of treatments. Malignancy and mortality in IBD have been associated with disease-related inflammation and immune suppression, but data are limited due to their rare occurrence. AIM: To identify and describe the most common causes of mortality, types of cancer and previous or current therapy among children and young adults with paediatric-onset IBD. METHODS: Information on paediatric-onset IBD patients diagnosed with malignancy or mortality was prospectively collected via a survey in 25 countries over a 42-month period. Patients were included if death or malignancy occurred after IBD diagnosis but before the age of 26 years. RESULTS: In total, 60 patients were identified including 43 malignancies and 26 fatal cases (9 due to cancer). Main causes of fatality were malignancies (n = 9), IBD or IBD-therapy related nonmalignant causes (n = 10; including 5 infections), and suicides (n = 3). Three cases, all fatal, of hepatosplenic T-cell lymphoma were identified, all were biologic-naïve but thiopurine-exposed. No other haematological malignancies were fatal. The 6 other fatal cancer cases included 3 colorectal adenocarcinomas and 3 cholangiocarcinomas (CCAs). Primary sclerosing cholangitis (PSC) was present in 5 (56%) fatal cancers (1 colorectal carcinoma, 3 CCAs and 1 hepatosplenic T-cell lymphoma). CONCLUSIONS: We report the largest number of paediatric-onset IBD patients with cancer and/or fatal outcomes to date. Malignancies followed by infections were the major causes of mortality. We identified PSC as a significant risk factor for cancer-associated mortality. Disease-related adenocarcinomas were a commoner cause of death than lymphomas.


Asunto(s)
Enfermedades Inflamatorias del Intestino/complicaciones , Enfermedades Inflamatorias del Intestino/mortalidad , Neoplasias/complicaciones , Neoplasias/mortalidad , Adolescente , Adulto , Edad de Inicio , Niño , Preescolar , Europa (Continente)/epidemiología , Femenino , Humanos , Lactante , Recién Nacido , Enfermedades Inflamatorias del Intestino/epidemiología , Masculino , Neoplasias/epidemiología , Estudios Prospectivos , Medición de Riesgo , Factores de Riesgo , Adulto Joven
5.
J Crohns Colitis ; 9(7): 558-64, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25895877

RESUMEN

BACKGROUND AND AIMS: Recent epidemiological studies showed an increase in ulcerative colitis among children, especially in its aggressive form, requiring surgical treatment. Although medical therapeutic strategies are standardized, there is still no consensus regarding indications, timing and kind of surgery. This study aimed to define the surgical management of paediatric ulcerative colitis and describe attitudes to it among paediatric surgeons. METHODS: This was a retrospective cohort study. All national gastroenterology units were invited to participate. From January 2009 to December 2013, data on paediatric patients diagnosed with ulcerative colitis that required surgery were collected. RESULTS: Seven units participated in the study. Seventy-one colectomies were performed (77.3% laparoscopically). Main surgical indications were a severe ulcerative colitis attack (33.8%) and no response to medical therapies (56.3%). A three-stage strategy was chosen in 71% of cases. Straight anastomosis was performed in 14% and J-pouch anastomosis in 86% of cases. A reconstructive laparoscopic approach was used in 58% of patients. Ileo-anal anastomosis was performed by the Knight-Griffen technique in 85.4% and by the pull-through technique in 9.1% of patients. Complications after colectomy, after reconstruction and after stoma closure were reported in 12.7, 19.3 and 35% of cases, respectively. CONCLUSIONS: This study shows that there is general consensus regarding indications for surgery. The ideal surgical technique remains under debate. Laparoscopy is a procedure widely adopted for colectomy but its use in reconstructive surgery remains limited. Longer follow-up must be planned to define the quality of life of these patients.


Asunto(s)
Actitud del Personal de Salud , Colitis Ulcerosa/cirugía , Gastroenterología , Proctocolectomía Restauradora/métodos , Adolescente , Niño , Preescolar , Colitis Ulcerosa/tratamiento farmacológico , Colostomía/efectos adversos , Defecación , Resistencia a Medicamentos , Incontinencia Fecal/etiología , Femenino , Humanos , Italia , Masculino , Reservoritis/etiología , Proctocolectomía Restauradora/efectos adversos , Estudios Retrospectivos , Índice de Severidad de la Enfermedad
6.
Anticancer Res ; 16(4B): 2221-3, 1996.
Artículo en Inglés | MEDLINE | ID: mdl-8694547

RESUMEN

Numerous tumor markers such as CEA, MCA, CA 15-3 have been assayed in breast cancer patients to detect relapse at a preclinical stage and most of all to monitor the treatment of the advanced disease. Since they are not site-specific, pyridinium crosslink dosage has recently been reported as a specific bone resorption marker in several non neoplastic diseases. The aim of this study was to evaluate the urinary pyridinium crosslink levels in breast cancer with or without osseous involvement, and to correlate it with serial doses of CA 15-3. 285 breast cancer patients (226 free of disease and 59 with bone metastases) were measured for both pyridinoline and CA 15-3. In the metastatic patients the mean values of the two markers were significantly higher than in non evident disease patients (P = < 0.01 and p = < 0.001 respectively). Abnormal values over the normal were found in 22% for pyridinoline and 11% for CA 15-3 in patients free of disease while the normal values observed in patients with bone metastases were 22% for pyridinoline and 39% for CA 15-3. Tandem dosage of CA 15-3, was highly sensitive but site-aspecific, and pyridinoline, which is bone specific, may be useful chiefly in the monitoring of breast cancer treatment, since many physiological conditions such as age, menopausal status and variation over 24 hours, and cost effectiveness will influence the use of pyridinoline during follow-up.


Asunto(s)
Aminoácidos/orina , Biomarcadores de Tumor/análisis , Neoplasias Óseas/diagnóstico , Neoplasias Óseas/secundario , Neoplasias de la Mama/diagnóstico , Mucina-1/sangre , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Persona de Mediana Edad
7.
Dig Liver Dis ; 42(2): 115-21, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19640811

RESUMEN

BACKGROUND & AIMS: In a group of children with suspected pulmonary aspiration, we aimed to describe the type and physical characteristics of gastro-oesophageal reflux (GOR) episodes, and to determine their correlation with the lipid-laden macrophage (LLM) content in bronchoalveolar lavage (BAL). PATIENTS AND METHODS: Twenty-one children with a diagnosis of bronchial asthma, recurrent lung consolidations and recurrent laryngotracheitis underwent 24-h multichannel intraluminal impedance and pH (MII-pH) monitoring, fibreoptic bronchoscopy and BAL. The following parameters were evaluated: total number of reflux episodes, number of acid reflux [AR; pH<4] and non-acid reflux [NAR] episodes [pH>4], height of reflux episodes, LLM content and percentage of neutrophils in the BAL. RESULTS: The number of NAR episodes and the number of those reaching the proximal oesophagus were significantly higher in patients with recurrent lung consolidations than in those with bronchial asthma and laryngotracheitis (p<0.01 and p<0.01). BAL studies showed a significantly higher LLM content in children with recurrent lung consolidations than in those with bronchial asthma and laryngotracheitis (p<0.01). The LLM content correlated significantly with the total number of reflux episodes (r=0.73; p<0.001) and with those reaching the proximal oesophagus (r=0.67; p<0.001). Finally, the LLM content correlated with the number of NAR episodes (r=0.61; p<0.01), with those reaching the proximal oesophagus (r=0.64; p<0.01) and with the percentage of BAL neutrophils (r=0.7; p<0.01). CONCLUSION: NAR episodes reaching the proximal oesophagus correlate with diagnostic marker for pulmonary micro-aspiration. MII-pH monitoring increases the yield in identifying types and proximal extension of reflux episodes, that discriminate between patients with and without pulmonary aspiration.


Asunto(s)
Líquido del Lavado Bronquioalveolar , Reflujo Gastroesofágico/complicaciones , Macrófagos , Neumonía por Aspiración/etiología , Asma , Broncoscopía , Recuento de Células , Niño , Preescolar , Estudios Transversales , Femenino , Reflujo Gastroesofágico/diagnóstico , Humanos , Masculino , Neutrófilos , Traqueítis/etiología
8.
Aliment Pharmacol Ther ; 32(8): 1017-22, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20937047

RESUMEN

BACKGROUND: Patients with ulcerative colitis often receive thiopurines as immunomodulators (IMs) to maintain remission and avoid corticosteroids. If unresponsive or intolerant to these agents, patients are treated with methotrexate, an antimetabolite never assessed in paediatric ulcerative colitis. AIM: To describe the experience with methotrexate in children with ulcerative colitis. METHODS: Thirty-two patients (median age 13.9 years) received methotrexate. Pediatric Ulcerative Colitis Activity Index (PUCAI) and use of corticosteroids were the main outcomes evaluated at baseline and at 3, 6 and 12 months. RESULTS: Indications to methotrexate were azathioprine unresponsiveness in 18 patients, azathioprine intolerance/toxicity in 10 and spondyloarthropathy in four. Response or remission was achieved in 72%, 63% and 50% of patients at 3, 6 and 12 months respectively. Mean PUCAI were 49.5 ± 23.3 at baseline and 32.9 ± 21.9, 29.5 ± 21.8 and 29.4 ± 19.9 at 3, 6 and 12 months respectively (P: 0.03). At the beginning of methotrexate, 16 patients (50%) received corticosteroids that were discontinued in 13 of them (81%) by 6 months. At the end of the study, 11 patients (33%) needed short courses of corticosteroids for disease relapse. CONCLUSIONS: Methotrexate may be useful in treating children with ulcerative colitis, although large, controlled trials are warranted to define better its effectiveness.


Asunto(s)
Antiinflamatorios/uso terapéutico , Antimetabolitos Antineoplásicos/uso terapéutico , Colitis Ulcerosa/tratamiento farmacológico , Metotrexato/uso terapéutico , Adolescente , Corticoesteroides/uso terapéutico , Niño , Femenino , Humanos , Estudios Longitudinales , Masculino , Inducción de Remisión , Estudios Retrospectivos
SELECCIÓN DE REFERENCIAS
Detalles de la búsqueda