70 research outputs found
PF191012 Myszyniec - highest Orionid meteor ever recorded
On the night of Oct 18/19, 2012 at 00:23 UT a -14.7 mag Orionid fireball
occurred over northeastern Poland. The precise orbit and atmospheric trajectory
of the event is presented, based on the data collected by five video and one
photographic Polish Fireball Network (PFN) stations. The beginning height of
the meteor is 168.4 +\- 0.6 km which makes the PF191012 Myszyniec fireball the
highest ever observed, well documented meteor not belonging to the Leonid
shower. The ablation became the dominant source of light of the meteor at a
height of around 115 km. The thermalization of sputtered particles is suggested
to be the source of radiation above that value. The transition height of 115 km
is 10-15 km below the transition heights derived for Leonids and it might
suggest that the material of Leonids should be more fragile and have probably
smaller bulk density than in case of Orionids.Comment: 5 pages, 5 figures, accpeted for publication in Astronomy &
Astrophysic
Fractional exhaled nitric oxide in preterm-born subjects: A systematic review and meta-analysis
Background
Decreased lung function is common in preterm‐born survivors. Increased fractional exhaled nitric oxide (FeNO) appears to be a reliable test for eosinophillic airway inflammation especially in asthma. We, systematically, reviewed the literature to compare FeNO levels in preterm‐born children and adults who did or did not have chronic lung disease of prematurity (CLD) in infancy with term‐born controls.
Methods
We searched eight databases up to February 2018. Studies comparing FeNO levels in preterm‐born subjects (<37 weeks’ gestation) in childhood and adulthood with and without (CLD) with term‐born subjects were identified and extracted by two reviewers. Data were analysed using Review Manager v5.3.
Results
From 6042 article titles, 183 full articles were screened for inclusion. Nineteen studies met the inclusion criteria. Seventeen studies compared FeNO levels in preterm‐ and term‐born children and adults; 11 studies (preterm n = 640 and term n = 4005) were included in a meta‐analysis. The mean FeNO concentration difference between the preterm‐born and term‐born group was −0.74 (95% CI −1.88 to 0.41) ppb. For the six studies reporting data on CLD (preterm n = 204 and term n = 211) the mean difference for FeNO levels was −2.82 (95% CI −5.87 to 0.22) ppb between the preterm‐born CLD and term‐born groups.
Conclusions
Our data suggest that preterm born children with and without CLD have similar FeNO levels to term‐born children suggesting an alternative mechanism to eosinophilic inflammation for symptoms of wheezing and airway obstruction observed in preterm‐born subjects
Multiple invasive species affect germination, growth, and photosynthesis of native weeds and crops in experiments
Alien plant species regularly and simultaneously invade agricultural landscapes and ecosystems; however, the effects of co-invasion on crop production and native biodiversity have rarely been studied. Secondary metabolites produced by alien plants may be allelopathic; if they enter the soil, they may be transported by agricultural activities, negatively affecting crop yield and biodiversity. It is unknown whether substances from different alien species in combination have a greater impact on crops and wild plants than if they are from only one of the alien species. In this study, we used a set of common garden experiments to test the hypothesis that mixed extracts from two common invasive species have synergistic effects on crops and weeds (defined as all non-crop plants) in European agricultural fields compared to single-species extracts. We found that both the combined and individual extracts had detrimental effects on the seed germination, seedling growth, biomass, and photosynthetic performance of both crops and weeds. We found that the negative effect of mixed extracts was not additive and that crop plants were more strongly affected by invasive species extracts than the weeds. Our results are important for managing invasive species in unique ecosystems on agricultural land and preventing economic losses in yield production
Extremely Low Birth Weight Predisposes to Impaired Renal Health: A Pooled Analysis
Background: A number of studies examined the association between preterm delivery and
kidney size and function later in life. However, the number of cases in published cohort studies is low. This study was aimed at performing a multicenter collaboration to pool data to obtain more accurate results to quantify the extent of renal impairment in former extremely low
birth weight (ELBW; <1,000 g) children. Methodology: We performed a subject-level metaanalysis to pool data from Cracow (64 cases/34 controls) and Leuven (93 cases/87 controls).
We assessed and analyzed cystatin C, estimated glomerular filtration rate (eGFR), ultrasound
kidney length, and blood pressure (BP) in 11-year-old ELBW children compared with controls
born at term. The prevalence of hypertension (HT) and prehypertension (preHT) in both
groups was also analyzed. Results: The study group comprised 157 former ELBW children
(gestational age 23–33 weeks and birth weight 430–1,000 g) and 123 children born at term.
Former ELBW children had lower mean eGFR (100.62 ± 16.53 vs. 111.89 ± 15.26 mL/min/1.73
m2; p < 0.001), smaller absolute kidney length (8.56 ± 0.78 vs. 9.008 ± 0.73 cm; <0.001), and
higher systolic (111.8 ± 9.8 vs. 107.2 ± 9.07 mm Hg; p = 0.01) and diastolic (68.6 ± 6.8 vs. 66.3
± 7.7 mm Hg; p = 0.03) BP. Smaller renal size in former ELBW children was positively associated with lower birth weight, shorter gestational age, and severity of perinatal complications
(intraventricular hemorrhage, length of stay, mechanical ventilation, and oxygen therapy).
Conclusion: ELBW is associated with lower eGFR and a high frequency of preHT and HT
Assessment of long-term renal complications in extremely low birth weight children
We assessed the long-term renal complications in a regional cohort of extremely low birth weight (ELBW) children born in 2002–2004. The study group, comprising 78 children born as ELBW infants (88% of the available cohort), was evaluated with measurement of serum cystatin C, urinary albumin excretion, renal ultrasound, and 24-h ambulatory blood pressure measurements. The control group included 38 children born full-term selected from one general practice in the district. Study patients were evaluated at a mean age of 6.7 years, and had a median birthweight of 890 g (25th–75th percentile: 760–950 g) and a median gestational age of 27 weeks (25th–75th percentile: 26–29 weeks). Mean serum cystatin C levels were significantly higher (0.64 vs. 0.59 mg/l; p = 0.01) in the ELBW group. Hypertension was diagnosed in 8/78 ELBW and 2/38 of the control children (p = 0.5). Microalbuminuria (>20 mg/g of creatinine) was detected only in five ELBW children (p = 0.17). The mean renal volume was significantly lower in the ELBW group (absolute kidney volume 81 ml vs. 113 ml; p < 0.001, relative kidney volume 85 vs. 97%; p < 0.001). Abnormally small kidneys (<2/3 of predicted size) were detected in 19 ELBW and four control children (p = 0.08). Multivariate logistic regression revealed that the only independent risk factor for renal complications was weight gained during neonatal hospitalization (odds ratio: 0.67; 95% confidence interval: 0.39–0.94). Serum cystatin C and kidney volume are significantly lower in school-age ELBW children. It is important to include systematic renal evaluation in the follow-up programs of ELBW infants
Can we improve outcome of congenital diaphragmatic hernia?
This review gives an overview of the disease spectrum of congenital diaphragmatic hernia (CDH). Etiological factors, prenatal predictors of survival, new treatment strategies and long-term morbidity are described. Early recognition of problems and improvement of treatment strategies in CDH patients may increase survival and prevent secondary morbidity. Multidisciplinary healthcare is necessary to improve healthcare for CDH patients. Absence of international therapy guidelines, lack of evidence of many therapeutic modalities and the relative low number of CDH patients calls for cooperation between centers with an expertise in the treatment of CDH patients. The international CDH Euro-Consortium is an example of such a collaborative network, which enhances exchange of knowledge, future research and development of treatment protocols
Bronchopulmonary dysplasia: clinical aspects and preventive and therapeutic strategies
Abstract Background Bronchopulmonary dysplasia (BPD) is the result of a complex process in which several prenatal and/or postnatal factors interfere with lower respiratory tract development, leading to a severe, lifelong disease. In this review, what is presently known regarding BPD pathogenesis, its impact on long-term pulmonary morbidity and mortality and the available preventive and therapeutic strategies are discussed. Main body Bronchopulmonary dysplasia is associated with persistent lung impairment later in life, significantly impacting health services because subjects with BPD have, in most cases, frequent respiratory diseases and reductions in quality of life and life expectancy. Prematurity per se is associated with an increased risk of long-term lung problems. However, in children with BPD, impairment of pulmonary structures and function is even greater, although the characterization of long-term outcomes of BPD is difficult because the adults presently available to study have received outdated treatment. Prenatal and postnatal preventive measures are extremely important to reduce the risk of BPD. Conclusion Bronchopulmonary dysplasia is a respiratory condition that presently occurs in preterm neonates and can lead to chronic respiratory problems. Although knowledge about BPD pathogenesis has significantly increased in recent years, not all of the mechanisms that lead to lung damage are completely understood, which explains why therapeutic approaches that are theoretically effective have been only partly satisfactory or useless and, in some cases, potentially negative. However, prevention of prematurity, systematic use of nonaggressive ventilator measures, avoiding supraphysiologic oxygen exposure and administration of surfactant, caffeine and vitamin A can significantly reduce the risk of BPD development. Cell therapy is the most fascinating new measure to address the lung damage due to BPD. It is desirable that ongoing studies yield positive results to definitively solve a major clinical, social and economic problem
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