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1.
Ital J Pediatr ; 49(1): 129, 2023 Sep 29.
Artículo en Inglés | MEDLINE | ID: mdl-37773131

RESUMEN

BACKGROUND: Coronary artery (CA) Z-score system is widely used to define CA aneurysm (CAA). Children and adolescents after acute stage of Kawasaki disease (KD-CA) have a higher risk of developing CAAs if their CA Z-score ≥ 2.5. Z-score system of peak oxygen consumption (Peak VO2 Z-score) allows comparisons across ages and sex, regardless of body size and puberty. We aimed to compare the exercise capacity (EC) indicated by peak VO2 Z-score during cardiopulmonary exercise testing (CPET) directly between KD-CA with different CA Z-score. METHODS: KD-CA after acute stage who received CPET in the last 5 years were retrospectively recruited. CA Z-score was based on Lambda-Mu-Sigma method. Max-Z was the maximum CA Z-score of different CAs. KD children with Max-Z < 2.5 and ≥ 2.5 were defined as KD-1 and KD-2 groups, respectively. Peak VO2 Z-score was calculated using the equation established based on Hong Kong Chinese children and adolescent database. RESULTS: One hundred two KD-CA were recruited (mean age: 11.71 ± 2.57 years). The mean percent of measured peak VO2 to predicted value (peak PD%) was 90.11 ± 13.33. All basic characteristics and baseline pulmonary function indices were comparable between KD-1 (n = 87) and KD-2 (n = 15). KD-1 had significantly higher peak VO2 Z-score (p = .025), peak PD% (p = .008), peak metabolic equivalent (p = .027), and peak rate pressure product (p = .036) than KD-2. CONCLUSIONS: KD-CA had slightly reduced EC than healthy peers. KD-CA with Max-Z ≥ 2.5 had significantly lower peak EC than those < 2.5. Max-Z is potentially useful follow-up indicator after acute stage of KD.


Asunto(s)
Síndrome Mucocutáneo Linfonodular , Humanos , Niño , Adolescente , Vasos Coronarios , Estudios Retrospectivos , Tolerancia al Ejercicio , Consumo de Oxígeno
2.
ACS Appl Mater Interfaces ; 14(35): 39917-39926, 2022 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-36000887

RESUMEN

Due to the sluggish kinetic reaction, the electrolytic oxygen evolution reaction (OER) is one of the obstacles in driving overall water splitting for green hydrogen production. In this study, we demonstrate a strategy to improve the OER performance of Ni3S2. The effect of addition of different FeCl2 contents during the hydrothermal process on the OER activity is systematically evaluated. We found that all samples upon the addition of FeCl2 produced Fe-doped Ni3S2 and FeS2 to form a nanocomposite. Their OER performances strongly depend on the amount of FeCl2, where the NSF-0.25 catalyst with 0.25 mmol FeCl2 added during the hydrothermal synthesis shows the best OER performance. Its overpotential was 230 mV versus RHE and it achieves a high current density of 100 mA·cm-2, which was much lower than that of pristine Ni3S2 (320 mV) or RuO2 (370 mV) as the benchmark OER catalyst. The postcharacterizations reveal that NSF-0.25 has gone through an in situ phase transformation into an Fe-NiOOH phase during the OER test. This study presents a simple method and a low-cost material to improve the OER performance with in situ formation of oxyhydroxide.

3.
Front Pediatr ; 10: 847343, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35402363

RESUMEN

Objective: Kawasaki disease (KD) is the most common form of pediatric vasculitis. We evaluated the influence of KD on cardiopulmonary function and analyzed the echocardiographic findings of patients with KD through serial follow-ups from childhood to adolescence. Methods: This was a retrospective study. We recruited patients with KD after the acute stage who underwent at least two (with >1-year interval between visits) cardiopulmonary exercise testing (CPET) and echocardiographic examinations in the last 10 years. Cardiopulmonary function was determined through CPET on a treadmill. The maximum Z score (Max-Z) of the proximal left anterior descending coronary artery or right coronary artery was determined using echocardiography. Healthy peers matched for age, sex, and body mass index with serial CPET and echocardiographic data were recruited as a control group. Results: Each group consisted of 30 participants with comparable basic characteristics. No significant differences in the variables of the first CPET were observed between the two groups. In the final CPET, the control group had a higher percentage of measured oxygen consumption (Vo2) at the anaerobic threshold (AT) to the predicted peak Vo2 (p = 0.016), higher percentage of measured peak Vo2 to the predicted peak Vo2 (p = 0.0004), and higher Vo2 at AT (p < 0.0001) than those of the KD group. No significant difference in the percentage of distribution of Max-Z was observed between the first and final echocardiographic examinations. Conclusions: Children with a history of KD had comparable exercise capacity to their healthy peers. However, in the follow-up, the aerobic metabolism and peak exercise load capacities of adolescents with KD were significantly lower than those of control adolescents.

4.
J Pediatr ; 238: 233-240.e1, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34228986

RESUMEN

OBJECTIVE: To analyze the aerobic fitness and evolution of exercise tolerance in patients with single-ventricle physiology after total cavopulmonary connection (TCPC) with an extracardiac conduit (ECC). STUDY DESIGN: This retrospective cohort study included patients with previous ECC-TCPC who underwent cardiopulmonary exercise testing (CPET) between September 2010 and September 2019. Patients who completed at least 2 tests (≥6 months apart) with adequate levels of effort were recruited for the serial CPET evaluation. RESULTS: We identified 70 patients (50% male) with a mean age of 6.45 ± 5.14 years at ECC-TCPC and 15.67 ± 5.03 years at the initial CPET. The peak oxygen consumption (peak VO2) to predicted value (peak PD) was 55.90 ± 16.81%. Twenty of the 70 identified patients (50% male) were recruited for serial analysis. The average number of CPETs was 2.6 per patient. The average duration from the first CPET to the last CPET was 3.64 years. The peak VO2 and PD increased slowly, with mean rates of 38.77 ± 129.01 mL/min and 1.66 ± 6.40%, respectively, during the study period. CONCLUSIONS: Although the patients had lower exercise tolerance after ECC-TCPC compared with their normal peers, exercise tolerance appears to have been preserved over the adolescent period in those who underwent serial testing after ECC-TCPC.


Asunto(s)
Umbral Anaerobio/fisiología , Prueba de Esfuerzo/métodos , Procedimiento de Fontan/efectos adversos , Adolescente , Niño , Preescolar , Femenino , Cardiopatías Congénitas/cirugía , Humanos , Lactante , Masculino , Estudios Retrospectivos , Taiwán
5.
PLoS One ; 14(10): e0223907, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31603948

RESUMEN

OBJECTIVE: Overweight and obesity in preschoolers might develop into childhood and even adulthood obesity. Overweight and obesity have been shown to be negatively related with cardiorespiratory fitness (CRF) in children and adults but few studies did among preschoolers. We aimed to evaluate whether excess body adipose is negatively associated with CRF in both the submaximal and maximal effort of preschool children in exercise testing and to examine if there is difference to achieve maximal effort during exercise testing between preschoolers with normal and excess body adipose. METHODS: Data of 106 preschoolers aged 4-6 that received symptom-limited treadmill exercise testing was analyzed. Anthropometry was measured by vector bioelectrical impedance analysis. Excess body adipose was defined as (1) 'overweight' and 'obesity' by body mass index (BMI), (2) fat mass index (FMI) greater than the sex- and age-specific 75th percentile of whole subjects, and (3) fat-free mass index (FFMI) smaller than the sex- and age-specific 25th percentile. CRF was indicated by metabolic equivalent (MET) at anaerobic threshold (AT MET), peak MET, oxygen uptake efficiency slope (OUES) calculated by the 50% (OUES-50) and the entire (OUES-100) duration of the exercise testing. RESULTS: Preschoolers with excess body adipose by three different definitions (BMI, FMI, and FFMI) all had poorer ability to perform maximal effort (p = 0.004, 0.043, and 0.007, respectively). Preschoolers with excess body adipose by BMI and FFMI classifications had lower OUES-50 (p = 0.018, and 0.001, respectively), and lower OUES-100 (p = 0.004, and 0.001, respectively) than peers with normal body adipose during exercise testing while those with excess body adipose by FMI classification showed no significant differences from peers with normal body adipose in both OUES-50 and OUES-100. CONCLUSIONS: Preschoolers with excess body adipose had lower CRF significantly during treadmill exercise testing. Weight control and health promotion should start as early as possible.


Asunto(s)
Capacidad Cardiovascular/fisiología , Obesidad/fisiopatología , Sobrepeso/fisiopatología , Antropometría , Composición Corporal , Índice de Masa Corporal , Niño , Preescolar , Estudios Transversales , Impedancia Eléctrica , Prueba de Esfuerzo , Femenino , Promoción de la Salud , Humanos , Masculino , Obesidad/epidemiología , Sobrepeso/epidemiología , Estudios Retrospectivos
6.
Mol Plant Pathol ; 17(4): 553-64, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26300048

RESUMEN

The soil-borne pathogen Ralstonia solanacearum causes bacterial wilt in a broad range of plants. The main virulence determinants of R. solanacearum are the type III secretion system (T3SS) and its associated type III effectors (T3Es), translocated into the host cells. Of the conserved T3Es among R. solanacearum strains, the Fbox protein RipG7 is required for R. solanacearum pathogenesis on Medicago truncatula. In this work, we describe the natural ripG7 variability existing in the R. solanacearum species complex. We show that eight representative ripG7 orthologues have different contributions to pathogenicity on M. truncatula: only ripG7 from Asian or African strains can complement the absence of ripG7 in GMI1000 (Asian reference strain). Nonetheless, RipG7 proteins from American and Indonesian strains can still interact with M. truncatula SKP1-like/MSKa protein, essential for the function of RipG7 in virulence. This indicates that the absence of complementation is most likely a result of the variability in the leucine-rich repeat (LRR) domain of RipG7. We identified 11 sites under positive selection in the LRR domains of RipG7. By studying the functional impact of these 11 sites, we show the contribution of five positively selected sites for the function of RipG7CMR15 in M. truncatula colonization. This work reveals the genetic and functional variation of the essential core T3E RipG7 from R. solanacearum. This analysis is the first of its kind on an essential disease-controlling T3E, and sheds light on the co-evolutionary arms race between the bacterium and its hosts.


Asunto(s)
Proteínas Bacterianas/química , Proteínas Bacterianas/metabolismo , Sistemas de Secreción Bacterianos , Ralstonia solanacearum/metabolismo , Selección Genética , Secuencia de Aminoácidos , Prueba de Complementación Genética , Medicago truncatula/microbiología , Modelos Moleculares , Mutagénesis Sitio-Dirigida , Mutación/genética , Filogenia , Enfermedades de las Plantas/microbiología , Ralstonia solanacearum/crecimiento & desarrollo , Ralstonia solanacearum/patogenicidad , Homología de Secuencia de Aminoácido , Virulencia
7.
Arch Microbiol ; 196(9): 667-74, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24938767

RESUMEN

Ralstonia solanacearum causes deadly wilting on many crops worldwide. However, the information on its components important for cell integrity and interactions with phages is limited. By systematically characterizing mutants resistant to a T7-like phage, we showed that the biosynthesis of rough lipopolysaccharides (R-LPS) was crucial for maintaining the membrane integrity, while the production of smooth LPS (S-LPS) was required for the resistance to polymyxin B and phage adsorption. Furthermore, RSc0154/ampG disruption did not affect LPS production and phage adsorption but may have caused aberrant release of peptidoglycan fragments, thus hindering phage DNA injection into or virion release from the cell. Mutations in the RSc2958-RSc2962/mla cluster, although not affecting LPS production, may have caused elevated phospholipid level in the outer leaflet of the outer membrane, consequently sheltering the mutants from phage adsorption on the O-antigen. These results specify important roles of the biogenesis and homeogenesis of envelope components for R. solanacearum-phage interaction.


Asunto(s)
Bacteriófagos/fisiología , Lipopolisacáridos/biosíntesis , Peptidoglicano/metabolismo , Fosfolípidos/metabolismo , Ralstonia solanacearum/genética , Ralstonia solanacearum/virología , Bacteriófagos/metabolismo , Pared Celular/metabolismo , Lipopolisacáridos/genética , Lipopolisacáridos/metabolismo , Mutación , Antígenos O/metabolismo , Fosfolípidos/genética
8.
Mol Plant Microbe Interact ; 27(5): 471-8, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24580105

RESUMEN

Lipopolysaccharides (LPS) are critical components for the fitness of most gram-negative bacteria. Ralstonia solanacearum causes a deadly wilting disease in many crops; however, the pathogenic roles of different forms of LPS and their pathways of biogenesis remain unknown. By screening for phage-resistant mutants of R. solanacearum Pss4, whose genome sequence is unavailable, mutants with various types of structural defects in LPS were isolated. Pathogenesis assays of the mutants revealed that production of rough LPS (R-LPS), which does not contain O-polysaccharides, was sufficient to cause necrosis on Nicotiana benthamiana and induce the hypersensitive response on N. tabacum. However, biosynthesis of smooth LPS (S-LPS), which contains O-polysaccharides, was required for bacterial proliferation at infection sites on N. benthamiana leaves and for proliferation and causing wilt on tomato. Complementation tests confirmed the involvement of the previously unidentified cluster RSc2201 to RSc2204 in the formation of R. solanacearum S-LPS. With these data and the availability of the annotated genomic sequence of strain GMI1000, certain loci involved in key steps of R. solanacearum LPS biosynthesis were identified. The strategy of this work could be useful for similar studies in other bacteria without available genome sequences.


Asunto(s)
Lipopolisacáridos/metabolismo , Enfermedades de las Plantas/microbiología , Ralstonia solanacearum/fisiología , Bacteriófagos/fisiología , Vías Biosintéticas , Biología Computacional , Prueba de Complementación Genética , Lipopolisacáridos/análisis , Solanum lycopersicum/microbiología , Mutagénesis Insercional , Hojas de la Planta/microbiología , Ralstonia solanacearum/genética , Ralstonia solanacearum/patogenicidad , Análisis de Secuencia de ADN , Nicotiana/microbiología , Virulencia , Factores de Virulencia
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