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11.
Exhaled nitric oxide is age-dependent in asthma 总被引:1,自引:0,他引:1
Avital A Uwyyed K Berkman N Bar-Yishay E Godfrey S Springer C 《Pediatric pulmonology》2003,36(5):433-438
We determined whether the exhaled nitric oxide (eNO) level in asthmatics is age-dependent. Eighty-seven asthmatic patients aged 2-41 years were studied. Hyperreactivity to adenosine 5'-monophosphate (AMP) was used to confirm asthma (= 200 mg/ml). In the younger group of children (2-5 years), AMP challenge was performed by the provocation concentration causing wheeze (PCW) method, while in the older groups of patients (6-41 years), regular spirometry was used. Exhaled NO was measured in the younger group by the tidal breathing method (TBm) and in the older subjects by the slow vital capacity method (SVCm). TBm and SVCm were compared in 21 other subjects, and there was a significant correlation between the two values (r = 0.96, P < 0.0001). The equation of correlation between the two methods was eNOTBm = 0.78eNOSVCm - 0.51. Within asthmatic patients, we found a significant increase in eNO with age (P < 0.0001), while there was no significant difference in AMP reactivity (P = 0.35). We conclude that eNO in asthmatic patients is age-dependent, with lower values in young children. 相似文献
12.
The growth and differentiation of the central nervous system are closely related to the presence of iodine and thyroid hormones. It has been hypothesized that neurobehavioral disabilities of childhood, such as attention deficit hyperactivity disorder (ADHD), learning disorders, and autism can be attributed to fetal thyroidal endocrine disruption in utero. To determine whether there is an association between neonatal thyroid status and a subsequent diagnosis of a neurobehavioral disability, neonatal thyroxine (T(4)) levels have been used as the indicator of the presence of intrauterine thyroidal dysfunction. Neonatal T(4) levels were obtained from the neonatal hypothyroidism screening program. All cases were diagnosed at medical school diagnostic clinics, the diagnostic categories being ADHD, autism spectrum disorder, behavioral disorder, cognitive disorder, developmental delay, emotional disorder, learning disability, and speech/language disorder. Conditional logistic regression analysis was performed for each clinical condition. Odds ratios for the conditions ranged from 0.92 to 1.13 with p values ranging between 0.19 and 0.84. No significant differences were detected between neonatal T(4) values of the cases and the controls for any of the neurobehavioral conditions. All neonatal T(4) values were within normal ranges. The data provide no evidence to suggest that intrauterine thyroid status as reflected by the neonatal T(4) values had an impact on the neurologic disorders diagnosed in childhood. 相似文献
13.
Svetlana Fischer Nancy Agmon-Levin Yinon Shapira Bat-Sheva Porat Katz Eduard Graell Ricard Cervera Ljudmila Stojanovich Jose A. Gómez Puerta Raimon Sanmartí Yehuda Shoenfeld 《Immunologic research》2013,56(2-3):287-292
Parasitic infections may induce variable immunomodulatory effects and control of autoimmune disease. Toxoplasma gondii (T. gondii) is a ubiquitous intracellular protozoan that was recently associated with autoimmunity. This study was undertaken to investigate the seroprevalence and clinical correlation of anti-T. gondii antibodies in patients with rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE). We evaluated sera from European patients with RA (n = 125) and SLE (n = 164) for the prevalence of anti-T. gondii IgG antibodies (ATXAb), as well as other common infections such as Cytomegalovirus, Epstein-Barr, and Rubella virus. The rates of seropositivity were determined utilizing the LIAISON chemiluminescent immunoassays (DiaSorin, Italy). Our results showed a higher seroprevalence of ATXAb in RA patients, as compared with SLE patients [63 vs. 36 %, respectively (p = 0.01)]. The rates of seropositivity of IgG against other infectious agents were comparable between RA and SLE patients. ATXAb-seropositivity was associated with older age of RA patients, although it did not correlate with RA disease activity and other manifestations of the disease. In conclusion, our data suggest a possible link between exposure to T. gondii infection and RA. 相似文献
14.
Adi Porat Rein Uri Kramer Moran Hausman Kedem Aviva Fattal-Valevski Alexis Mitelpunkt 《Brain & development》2021,43(2):268-279
BackgroundMost children with Benign epilepsy with centro-temporal spikes (BECTS) undergo remission during late adolescence and do not require treatment. In a small group of patients, the condition may evolve to encephalopathic syndromes including epileptic encephalopathy with continuous spike-and-wave during sleep (ECSWS), or Landau-Kleffner Syndrome (LKS). Development of prediction models for early identification of at-risk children is of utmost importance.AimTo develop a predictive model of encephalopathic transformation using data-driven approaches, reveal complex interactions to identify potential risk factors.MethodsData were collected from a cohort of 91 patients diagnosed with BECTS treated between the years 2005–2017 at a pediatric neurology institute. Data on the initial presentation was collected based on a novel BECTS ontology and used to discover potential risk factors and to build a predictive model. Statistical and machine learning methods were compared.ResultsA subgroup of 18 children had encephalopathic transformation. The least absolute shrinkage and selection operator (LASSO) regression Model with Elastic Net was able to successfully detect children with ECSWS or LKS. Sensitivity and specificity were 0.83 and 0.44. The most notable risk factors were fronto-temporal and temporo-parietal localization of epileptic foci, semiology of seizure involving dysarthria or somatosensory auras.ConclusionNovel prediction model for early identification of patients with BECTS at risk for ECSWS or LKS. This model can be used as a screening tool and assist physicians to consider special management for children predicted at high-risk. Clinical application of machine learning methods opens new frontiers of personalized patient care and treatment. 相似文献
15.
P. Yagupsky A. Slonim U. Amit N. Porat R. Dagan 《European journal of clinical microbiology & infectious diseases》2013,32(8):1049-1053
The purpose of this study was to investigate the prevalence of β-lactamase and the genomic clonality of a large collection of Kingella kingae isolates from Israeli patients with a variety of invasive infections and asymptomatic pharyngeal carriers. β-lactamase production was studied by the nitrocefin method and the minimum inhibitory concentrations (MICs) of penicillin and amoxicillin–clavulanate were determined by the epsilon (Etest) method. The genotypic clonality of isolates was investigated by pulsed-field electrophoresis (PFGE). β-lactamase was found in 2 of 190 (1.1 %) invasive isolates and in 66 of 429 (15.4 %) randomly chosen carriage organisms (p?<?0.001). Overall, 73 distinct PFGE clones were identified (33 among invasive organisms and 56 among carriage isolates). β-lactamase production was found to be limited to four distinct PFGE clones, which were common among carriage strains but rare among invasive strains, and all organisms in the collection belonging to these four clones expressed β-lactamase. The penicillin MIC of β-lactamase-producing isolates ranged between 0.094 and 2 mcg/mL (MIC50: 0.25 mcg/mL; MIC90: 1.5 mcg/mL) and that of amoxicillin–clavulanate between 0.064 and 0.47 mcg/mL (MIC50: 0.125 mcg/mL; MIC90: 0.125 mcg/mL). The penicillin MIC of β-lactamase non-producing isolates ranged between <0.002 and 0.064 mcg/mL (MIC50: 0.023 mcg/mL; MIC90: 0.047 mcg/mL). Although β-lactamase production is prevalent among K. kingae organisms carried by healthy carriers, the low invasive potential of most colonizing clones results in infrequent detection of the enzyme in isolates from patients with clinical infections. The exceptional presence of β-lactamase among invasive organisms correlates with the favorable response of K. kingae infections to the administration of β-lactamase-susceptible antibiotics. 相似文献
16.
Ortenberg R Gon S Porat A Beckwith J 《Proceedings of the National Academy of Sciences of the United States of America》2004,101(19):7439-7444
A strain of Escherichia coli missing three members of the thioredoxin superfamily, thioredoxins 1 and 2 and glutaredoxin 1, is unable to grow, a phenotype presumed to be due to the inability of cells to reduce the essential enzyme ribonucleotide reductase. Two classes of mutations can restore growth to such a strain. First, we have isolated a collection of mutations in the gene for the protein glutaredoxin 3 that suppress the growth defect. Remarkably, all eight independent mutations alter the same amino acid, methionine-43, changing it to valine, isoleucine, or leucine. From the position of the amino acid changes and their effects, we propose that these alterations change the protein so that its properties are closer to those of glutaredoxin 1. The second means of suppressing the growth defects of the multiply mutant strain was by mutations in the DNA replication genes, dnaA and dnaN. These mutations substantially increase the expression of ribonucleotide reductase, most likely by altering the interaction of the regulatory protein DnaA with the ribonucleotide reductase promoter. Our results suggest that this increase in the concentration of ribonucleotide reductase in the cell allows more effective interaction with glutaredoxin 3, thus restoring an effective pool of deoxyribonucleotides. Our studies present direct evidence that ribonucleotide reductase is the only essential enzyme that requires the three reductive proteins missing in our strains. Our results also suggest an unexpected regulatory interaction between the DnaA and DnaN proteins. 相似文献
17.
Detailed Transabdominal Fetal Anatomic Scanning in the Late First Trimester Versus the Early Second Trimester of Pregnancy 下载免费PDF全文
18.
Hagai Yanai Albert Shteinberg Ziv Porat Arie Budovsky Alex Braiman Rolf Zeische Vadim E. Fraifeld 《Aging》2015,7(9):664-672
Idiopathic pulmonary fibrosis (IPF) is an age-related fatal disease with unknown etiology and no effective treatment. In this study, we show that primary cultures of fibroblasts derived from lung biopsies of IPF patients exhibited (i) accelerated replicative cellular senescence (CS); (ii) high resistance to oxidative-stress-induced cytotoxicity or CS; (iii) a CS-like morphology (even at the proliferative phase); and (iv) rapid accumulation of senescent cells expressing the myofibroblast marker α-SMA. Our findings suggest that CS could serve as a bridge connecting lung aging and its quite frequent outcome -- pulmonary fibrosis, and be an important player in the disease progression. Consequently, targeting senescent cells offers the potential of being a promising therapeutic approach. 相似文献
19.
20.
A novel potential therapy for vascular diseases: blood‐derived stem/progenitor cells specifically activated by dendritic cells 下载免费PDF全文