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1.
Sci Total Environ ; 626: 1439-1462, 2018 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-29898550

RESUMEN

Since its founding in 1993 the International Long-term Ecological Research Network (ILTER) has gone through pronounced development phases. The current network comprises 44 active member LTER networks representing 700 LTER Sites and ~80 LTSER Platforms across all continents, active in the fields of ecosystem, critical zone and socio-ecological research. The critical challenges and most important achievements of the initial phase have now become state-of-the-art in networking for excellent science. At the same time increasing integration, accelerating technology, networking of resources and a strong pull for more socially relevant scientific information have been modifying the mission and goals of ILTER. This article provides a critical review of ILTER's mission, goals, development and impacts. Major characteristics, tools, services, partnerships and selected examples of relative strengths relevant for advancing ILTER are presented. We elaborate on the tradeoffs between the needs of the scientific community and stakeholder expectations. The embedding of ILTER in an increasingly collaborative landscape of global environmental observation and ecological research networks and infrastructures is also reflected by developments of pioneering regional and national LTER networks such as SAEON in South Africa, CERN/CEOBEX in China, TERN in Australia or eLTER RI in Europe. The primary role of ILTER is currently seen as a mechanism to investigate ecosystem structure, function, and services in response to a wide range of environmental forcings using long-term, place-based research. We suggest four main fields of activities and advancements for the next decade through development/delivery of a: (1) Global multi-disciplinary community of researchers and research institutes; (2) Strategic global framework and strong partnerships in ecosystem observation and research; (3) Global Research Infrastructure (GRI); and (4) a scientific knowledge factory for societally relevant information on sustainable use of natural resources.

2.
Eur Respir J ; 38(6): 1336-42, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21622589

RESUMEN

The aim of our study was to evaluate the responses to an exercise programme with respect to initial fitness in subjects with cystic fibrosis (CF). 72 subjects (42 female) aged 10-43 yrs (forced expiratory volume in 1 s of 62.0 ± 26.7% predicted) were included. Participants were divided into three groups based on peak oxygen uptake expressed as % predicted. Subjects participated in a multifaceted rehabilitation programme, including five-times-a-week exercise training, for 6 weeks. Exercise and ventilatory capacity were determined by a maximal incremental cycling test. Oxygen uptake, workload and peak cardiac frequency at peak and submaximal workload were used as parameters for exercise capacity and responsiveness to training. Lung function values were significantly different between groups (p < 0.05), and increased after training (p < 0.05) only in groups with a lower initial fitness level. Responsiveness to training showed differences between groups (p < 0.05) at peak and ventilatory anaerobic threshold (VAT; p < 0.05), with higher improvements in subjects with lower initial fitness level. The improvements in exercise parameters in CF at peak and VAT depended on the fitness level at baseline, independent of lung function. These improvements seen after training were comparable with those seen in healthy subjects, suggesting that responsiveness to exercise is similar in CF and in healthy untrained persons.


Asunto(s)
Fibrosis Quística/terapia , Terapia por Ejercicio , Aptitud Física/fisiología , Adolescente , Adulto , Umbral Anaerobio/fisiología , Niño , Fibrosis Quística/fisiopatología , Prueba de Esfuerzo , Tolerancia al Ejercicio/fisiología , Femenino , Frecuencia Cardíaca/fisiología , Humanos , Masculino , Consumo de Oxígeno/fisiología , Resultado del Tratamiento , Adulto Joven
3.
Pediatr Pulmonol ; 43(10): 953-64, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18781654

RESUMEN

The objective of this study was to examine the effects of a supervised exercise training program performed during an in patient rehabilitation course on various attributes of health-related fitness, e.g., flexibility, balance and coordination. 286 patients with CF, age range 6-18 years (11.8 +/- 3.4 years), mean forced expiratory volume in 1 sec (FEV1 82.7 +/- 22.3% predicted) were included. Patients performed the modified Munich fitness test (mMFT) to assess flexibility, balance, strength and coordination. To assess aerobic capacity a 6-min walk-test (6MWT) was performed. In addition, some of the patients performed an incremental exercise test on a bicycle ergometer using the Godfrey protocol before and after the exercise training program. The supervised training program consisted of 4-6 weeks of different sports activities 5 times per week. After training, pulmonary function showed a significant (P < 0.05) increase. All test items of the mMFT improved significantly (P < 0.05). Compared to healthy children test scores achieved from children with CF in the mMFT were lower but within a normal range. Our children with CF had a lower walk distance in 6MWT (P < 0.05) compared to healthy. Our findings clearly demonstrated benefits of a systematic exercise training program on components of physical fitness in patients with CF, with improvements of test-tasks to predicted normal in some cases. The results from our study suggested that an exercise training program in CF should be focused on several aspects of physical fitness including all components of physical fitness, e.g. aerobic endurance, flexibility, balance and motor skills.


Asunto(s)
Fibrosis Quística/rehabilitación , Terapia por Ejercicio , Tolerancia al Ejercicio/fisiología , Adolescente , Niño , Femenino , Humanos , Masculino , Aptitud Física
6.
Pediatr Pulmonol ; 31(6): 474-7, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11389581

RESUMEN

Cystic fibrosis (CF) and bronchopulmonary dysplasia (BPD) are two common causes of chronic lung disease in children. Patients with BPD or CF often have recurrent respiratory symptoms, failure to thrive, and/or metabolic alkalosis during infancy and childhood. Thus, recognizing the diagnosis of CF in an infant with BPD can be difficult. We present three infants with both BPD and CF. The infants shared a history of respiratory distress and prolonged oxygen requirements. All three also had difficulty gaining weight, even after pancreatic enzyme supplementation was instituted. Metabolic alkalosis was observed in two infants. Previous studies in children with CF suggest that early diagnosis may impact both lung health and nutritional status. A high index of suspicion is necessary for clinicians to identify these children early and intervene with appropriate therapy.


Asunto(s)
Displasia Broncopulmonar/patología , Fibrosis Quística/patología , Alcalosis , Displasia Broncopulmonar/etiología , Preescolar , Fibrosis Quística/diagnóstico , Fibrosis Quística/etiología , Diagnóstico Diferencial , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Estado Nutricional , Oxígeno/uso terapéutico , Síndrome de Dificultad Respiratoria del Recién Nacido/terapia , Aumento de Peso
7.
Med Sci Sports Exerc ; 33(1): 30-5, 2001 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11194108

RESUMEN

PURPOSE: This study was conducted to: 1) measure total physical activity levels, including the intensities of the various types of activities, in children and adolescents with CF compared with non-CF healthy control subjects; and 2) determine whether vigorous activity level was related to aerobic fitness and disease status in patients with CF. METHODS: Thirty patients with CF (18 male, 12 female) and 30 control subjects (17 male, 13 female), 7-17 yr old, participated in this study. Habitual physical activity was measured using Kriska's Modifiable Activity Questionnaire (MAQ) and the past year's average of total hours, MET-hours, and vigorous (VIG) hours (>6 METs) of activity per week were determined. Aerobic fitness was determined from peak oxygen uptake (VO2peak) obtained via maximal exercise testing on a cycle ergometer. Standard spirometry was used to measure pulmonary function. Body mass index (BMI) was determined from height and weight measurements. RESULTS: The CF and control groups were similar in age and gender distribution, but the patients were smaller (BMI, 98 vs 112% of predicted) and less aerobically fit (36.5 vs 41.4 mL x kg(-1) x min(-1)). Total and MET-hours of physical activity did not differ between groups; however, the CF group participated in significantly fewer hours of vigorous activities than the control group (2 vs 3.7 h x wk(-1)). In patients with worse lung disease, VIG-h x wk(-1) were significantly related to VO2peak (r = 0.83). CONCLUSION: These results suggest that children with CF engage in less vigorous physical activities than their healthy non-CF peers, despite having good lung function. In view of the progressive nature of the disease, and the association between aerobic fitness and vigorous activity, patients should be encouraged to engage in more vigorous activities that promote aerobic fitness and may ultimately have an impact on survival.


Asunto(s)
Fibrosis Quística/fisiopatología , Ejercicio Físico , Adolescente , Estudios de Casos y Controles , Niño , Prueba de Esfuerzo , Femenino , Humanos , Masculino , Aptitud Física , Pruebas de Función Respiratoria
9.
Am J Gastroenterol ; 95(8): 1932-8, 2000 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10950038

RESUMEN

OBJECTIVE: The safety and efficacy of Minimicrospheres, which are enteric-coated, delayed-release pancrelipase capsules, on fat absorption in pediatric/adolescent and adult cystic fibrosis (CF) patients was assessed. Exocrine pancreatic insufficiency, common in CF patients, causes steatorrhea due to insufficient release of pancreatic enzymes. METHODS: In the open-label phase, 97 CF patients with pancreatic insufficiency and steatorrhea were stabilized on a high-fat diet and administered pancrelipase. Seventy-four patients with >80% coefficient of fat absorption received placebo or pancrelipase in the double-blind phase. Fat intake and excretion, stool frequency and consistency, and clinical global improvement were recorded. RESULTS: Average daily fat intake was comparable between treatment groups within each age group (adults vs pediatric/adolescent), but placebo patients had a significant (p < 0.001) mean decrease in coefficient of fat absorption (adult, 36.9 percentage points; pediatric/adolescent, 34.9 percentage points) from open-label to double-blind treatment compared to pancrelipase patients (adult, 2 percentage points; pediatric/adolescent, 3.25 percentage points); this difference was caused by a greater (p < or = 0.001) increase in mean fecal fat excretion (grams per day) in the placebo groups compared to pancrelipase groups (adult: 61.9 vs 2.3; pediatric/adolescent: 45.4 vs 4.1). Change in mean stool frequency from open-label to double-blind phases was significantly different (p < or = 0.002) between treatment groups, with increases in placebo groups and no difference (adult) or decrease (pediatric/adolescent) in pancrelipase groups. Pancrelipase patients' stool consistency remained about the same from open-label to double-blind. Placebo patients' stool consistency decreased (became softer) from open-label pancrelipase to double-blind placebo. Clinical global improvement data showed that > or =83% of pancrelipase patients improved or remained unchanged. CONCLUSIONS: Enteric-coated, delayed-release (Minimicrospheres) pancrelipase capsules are an effective treatment for steatorrhea associated with pancreatic insufficiency in patients with cystic fibrosis.


Asunto(s)
Enfermedad Celíaca/tratamiento farmacológico , Enfermedad Celíaca/etiología , Fibrosis Quística/complicaciones , Insuficiencia Pancreática Exocrina/etiología , Fármacos Gastrointestinales/efectos adversos , Fármacos Gastrointestinales/uso terapéutico , Pancrelipasa/efectos adversos , Pancrelipasa/uso terapéutico , Adulto , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Femenino , Humanos , Masculino , Placebos/efectos adversos , Placebos/uso terapéutico , Factores de Tiempo
10.
Neurosurgery ; 46(3): 744-7, 2000 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10719873

RESUMEN

OBJECTIVE AND IMPORTANCE: Intracranial fibrous tumors are uncommon during childhood. An unusual case of benign intrasylvian "fibroma" that has remained clinically and radiographically stable more than 3 years after a subtotal resection is described. CLINICAL PRESENTATION: A 9-year-old girl with cystic fibrosis presented with new-onset focal seizures referable to a large calcified left sylvian fissure mass. INTERVENTION: An open biopsy with subtotal resection of the lesion revealed a benign process characterized by exuberant fibrocollagenous tissue intermeshed with chronic inflammatory cells and foreign body giant cells, encompassing islands of gliotic brain tissue. Immunohistochemical analysis showed staining for epithelial membrane antigen and reticulin within some of the spindle cells, although the majority were nonreactive. The majority of tumor cells exhibited staining for laminin; CD34 staining was absent. Ultrastructural studies were also suggestive of a fibroblastic rather than a meningothelial origin of the lesion, with elongated cells separated by abundant extracellular collagen. Although dense adherence of the mass to the pial surface and the middle cerebral artery vessels precluded a complete resection, the patient remains seizure-free without anticonvulsant therapy more than 3 years postoperatively with no evidence of growth of the lesion. CONCLUSION: The lesion in this patient bears morphological similarity to a rare group of tumors referred to as "intracerebral fibromas," although a variety of other rare mesenchymal neoplasms were also considered within the differential diagnosis. However, the absence of any definite neoplastic features, the finding of chronic inflammatory changes, and the lack of growth of the residual tumor during an extended follow-up interval indicate that the mass may represent either an extremely indolent neoplasm or a nonneoplastic process. The differential diagnosis of intracranial fibrous tumors is contrasted with that of the reported case.


Asunto(s)
Neoplasias Encefálicas/complicaciones , Acueducto del Mesencéfalo , Fibrosis Quística/complicaciones , Fibroma/complicaciones , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/patología , Neoplasias Encefálicas/cirugía , Niño , Diagnóstico Diferencial , Femenino , Fibroma/diagnóstico , Fibroma/patología , Fibroma/cirugía , Humanos , Imagen por Resonancia Magnética , Inducción de Remisión , Convulsiones/etiología , Tomografía Computarizada por Rayos X
11.
Pediatr Pulmonol ; 28(4): 255-60, 1999 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-10497374

RESUMEN

Chest physiotherapy (CPT) is recommended for the clearance of bronchial secretions in the management of patients with cystic fibrosis (CF). The Flutter valve (Scandipharm, Birmingham, AL) has been introduced as an alternative method to CPT for airway mucus clearance. The objective of this study was to compare the short-term effects of CPT and the Flutter valve on pulmonary function and exercise tolerance in patients with cystic fibrosis. Twenty-three patients, 5 to 21 years of age, were randomized to receive one of two interventions: CPT or the Flutter valve, upon admission to the hospital for a 2-week treatment of pulmonary exacerbation. Pulmonary function testing (PFTs) and the 6-min walk test were performed on admission, day 7, and day 14 of hospitalization. Data analysis indicated no significant differences between the two groups on admission. Both groups showed improvement in pulmonary function test results, but the Flutter group had a higher mean forced vital capacity (FVC) and forced expiratory volume in 1 sec (FEV(1)) compared to the CPT group after 1 week of intervention. Both groups continued to improve during the 2-week intervention, with no significant difference in FVC or FEV(1) between groups by the end of 2 weeks. Mean forced expiratory flow rate between 25-75% of vital capacity (FEF(25-75)), 6-min walk distance, and resting arterial oxyhemoglobin saturation (SaO(2)) showed little change by day 7, but improved significantly (P< 0.05) by day 14 of hospitalization in both groups, with no significant difference between groups. This study demonstrated that patients using the Flutter device had better pulmonary function after 1 week of therapy and similar improvement in pulmonary function and exercise tolerance compared to CPT after 2 weeks of therapy, suggesting that Flutter valve therapy is an acceptable alternative to standard CPT during in-hospital care of patients with CF.


Asunto(s)
Fibrosis Quística/rehabilitación , Modalidades de Fisioterapia , Terapia Respiratoria/instrumentación , Adolescente , Adulto , Análisis de Varianza , Niño , Preescolar , Fibrosis Quística/diagnóstico , Fibrosis Quística/fisiopatología , Drenaje Postural/métodos , Tolerancia al Ejercicio , Femenino , Volumen Espiratorio Forzado , Humanos , Masculino , Modalidades de Fisioterapia/métodos , Recurrencia , Terapia Respiratoria/métodos , Sensibilidad y Especificidad , Resultado del Tratamiento , Vibración
14.
Dysphagia ; 12(4): 207-11, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9294941

RESUMEN

Esophageal venting following air insufflation may occur by secondary peristalsis or by isolated transient lower esophageal sphincter relaxation (TLESR). To identify factors determining venting by these two mechanisms, we analyzed the responses to esophageal air insufflation in 4 infants and in 2 adults. We used a nine-lumen dual-Dent-sleeve manometric catheter with an air insufflation esophageal side hole, identifying swallowing by pharyngeal manometry or submental electromyography. The time from the venting lower esophageal sphincter relaxation (whether part of a secondary peristalsis or an isolated TLESR) to the next swallow (whether spontaneous, in the infants, or on command, in the adults) was characterized as > or = 15 sec or < 15 sec. Of the 25 evaluable trials, the subsequent swallow was > or = 15 sec after the venting response in 9 instances and < 15 sec afterward in 16 instances. Eight of the 9 trials with delayed swallows (> or = 15 sec) were vented by secondary peristalsis, whereas 11 of the 16 with early swallows (< 15 sec) were vented by TLESR (X2 p < 0.01). TLESRs may be induced by esophageal stimuli, in which case they may represent "wave-suppressed" secondary peristaltic complexes.


Asunto(s)
Esófago/fisiología , Relajación Muscular , Adulto , Trastornos de Deglución/diagnóstico , Electromiografía/métodos , Humanos , Lactante , Recién Nacido , Insuflación/instrumentación , Masculino , Manometría/instrumentación , Persona de Mediana Edad , Peristaltismo
15.
Pediatr Pulmonol ; 23(2): 87-94, 1997 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9065945

RESUMEN

Maximum expiratory and inspiratory flow-volume (MEFV, MIFV) curves, specific airway conductance (sGaw), and flexible fiberoptic laryngoscopy were examined in 8 pediatric lung transplant recipients with vocal cord paralysis (VCP). Six were heart-lung (H-L) and 2 double-lung (D-L) recipients, 7 had left VCP, and 1 had right VCP. Based on the pulmonary function tests (PFT), 2 subgroups could be distinguished in the 8 recipients with VCP. Group A (5/8 recipients; mean age, 13 +/- 3.4 years; mean height, 144.3 +/- 12.3 cm) had significantly reduced specific airway conductance (sGaw; < 2 SD from predicted) and normal MEF25, MEF50, peak expiratory flow (PEF), forced expiratory volume in 1 second (FEV1), and %FEV1/forced vital capacity (FVC); this pattern suggested variable extrathoracic airway obstruction. PIF was normal in 4/5 and reduced in 1/5 of these recipients. Group B (3/8 recipients with VCP; mean age, 17 +/- 2.4 years; mean height, 156.3 +/- 12.0 cm) had significantly reduced sGaw, MEF25, MEF50, PEF, FEV1, and %FEV1/FVC, implying primarily small airway obstruction. These recipients had bronchiolitis obliterans. The results suggest that a pattern of reduced sGaw and normal MEFs, PEF, FEV1, and PIF should raise the possibility of VCP in patients after lung transplantation. sGaw is more sensitive than PIF and PEF in identifying airway obstruction due to VCP, and should be routinely included in the follow-up evaluation of lung transplant recipients.


Asunto(s)
Trasplante de Pulmón , Complicaciones Posoperatorias/fisiopatología , Pruebas de Función Respiratoria , Parálisis de los Pliegues Vocales/fisiopatología , Adolescente , Niño , Femenino , Volumen Espiratorio Forzado , Humanos , Laringoscopía , Trasplante de Pulmón/fisiología , Masculino , Complicaciones Posoperatorias/etiología , Ventilación Pulmonar , Parálisis de los Pliegues Vocales/etiología
17.
J Pediatr ; 129(6): 846-55, 1996 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-8969726

RESUMEN

OBJECTIVES: To determine the immunologic response to a brief bout of intense exercise in children and to determine the effects of prolonged activity and maturation level of the subjects on this response. STUDY DESIGN: We determined counts of leukocytes and their subsets, counts of lymphocytes and their subsets, and natural killer (NK) cell activity and cell number before and 3 and 60 minutes after a Wingate anaerobic test (WAnT) in 16 male swimmers (9 to 17 years of age) and 17 male nonswimmers (9 to 17 years of age). Subjects were also categorized by pubertal status based on Tanner staging and by level of physical activity. The Student t test and analysis of variance were used to determine statistical significance, with values expressed as mean +/- SEM. RESULTS: Three minutes after the WAnT, all children had increases in leukocytes (28%), lymphocytes (43%), and NK cells (395%) (p < 0.01). Swimmers had less baseline NK cell activity (54 +/- 6 cytolytic units) than nonswimmers (87 +/- 10 cytolytic units) after the WAnT (p < 0.01), although both groups showed an increase to similar levels of NK activity 3 minutes after exercise. Pubertal effects on these responses were not significant. CONCLUSIONS: Our results demonstrate transient leukocytosis, lymphocytosis, and increases in NK cell number and activity in 8- to 17-year-old boys after a brief bout of intense exercise. Formal athletic training appears to be associated with a lower baseline NK cell activity, and yet such activity is still within the normal range for this age group. Further investigations are necessary to determine the impact of such training on overall health and the ability to fight infection.


Asunto(s)
Ejercicio Físico/fisiología , Sistema Inmunológico/inmunología , Aptitud Física/fisiología , Adolescente , Anaerobiosis , Análisis de Varianza , Niño , Prueba de Esfuerzo , Humanos , Inmunidad Celular/fisiología , Masculino , Examen Físico , Pubertad/inmunología , Natación/fisiología , Factores de Tiempo
18.
Presse Med ; 25(33): 1592-4, 1996 Nov 02.
Artículo en Francés | MEDLINE | ID: mdl-8952674

RESUMEN

Pituitary stimulation tests are widely used to explore hypophyseal adenomas. There are few disadvantages, although a few cases of pituitary necrosis have been published. We report a new case with a dramatic outcome. A 30-year-old man with clinical signs of acromegalia and major visual disorders was found to have a voluminous macro-adenoma of the pituitary gland. Thirty minutes after beginning the stimulation test, the patient complained of major headache and experienced persistant vomiting for several hours. Brain magnetic resonance imaging the next day did not reveal evidence of pituitary necrosis. Sudden onset coma occurred one hour later. The CT scan demonstrated hemorrhagic necrosis of the adenoma. The patient died despite emergency surgery. Due to the risk of hemorrhagic necrosis of a pituitary adenoma, baseline assays may be sufficient for diagnosis in patients with clinical signs highly suggestive of pituitary oversecretion, especially when a voluminous tumor is involved. Rigorous clinical surveillance is required after stimulation tests.


Asunto(s)
Adenoma/fisiopatología , Hemorragia Cerebral/etiología , Pruebas de Función Hipofisaria/efectos adversos , Neoplasias Hipofisarias/fisiopatología , Adenoma/patología , Adulto , Resultado Fatal , Humanos , Masculino , Necrosis , Neoplasias Hipofisarias/patología
20.
J Pediatr Psychol ; 21(2): 209-35, 1996 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8920154

RESUMEN

Critiqued previous conceptual and methodological approaches to the measurement of stress and coping. Applied Goldfried and D'Zurilla's behavior-analytic model to create a context-specific measure of problematic situations and coping strategies for parents of school-age children with cystic fibrosis (CF). The sample was stratified by child's gender and illness severity. Forty-seven families (46 mothers, 32 fathers) and 8 health care professionals completed structured interviews or daily diaries to obtain the widest range of problematic situations; 1,725 situations were elicited across all participants and then content-analyzed into 97 nonredundant categories in 11 domains (e.g., Discipline, Medical Care). Few differences were found in problem frequency or difficulty as a function of either gender or illness severity. Using empirical criteria, the most frequent and difficult problem situations were selected and developed into role-play vignettes that include relevant contextual, developmental, and interactional details. The Role-Play Inventory of Situations and Coping Strategies (RISCS) consists of 31 audiotaped vignettes designed to elicit and evaluate the coping strategies used by parents of children with CF.


Asunto(s)
Adaptación Psicológica , Fibrosis Quística/psicología , Padres/psicología , Psicometría/métodos , Desempeño de Papel , Adulto , Niño , Femenino , Humanos , Indiana , Masculino , Modelos Psicológicos , Pennsylvania , Reproducibilidad de los Resultados
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