bluuebunny/crossref_metadata_2025 huggingface dataset:
Diagnostic value of different electrocardiographic voltage criteria for hypertrophic cardiomyopathy in young people
Authors: Erice B. , Romero C. , Andériz M. , Gorostiaga E. , Izquierdo M. , Ibáñez J.
Published: February 2010

Differences in the diagnostic value of various electrocardiographic (ECG) voltage indices for hypertrophic cardiomyopathy (HCM) are yet to be elucidated. The objective of this study was to examine the strongest predictor within ECG voltage criteria for left ventricular hypertrophy (LVH) in HCM to be applied in cardiovascular examination of young people. The electrocardiograms of 36 healthy individuals with high voltages, mimicking HCM (i.e., false‐positive), were statistically compared with those of 30 subjects with an ECG diagnosis of HCM. The most striking ECG voltages observed in HCM patients were those included in leads DI, aVL (R wave) and V3 (S wave) (P<0.001), typically present in the Cornell, Gubner and Lewis voltage criteria. In a stepwise logistic regression analysis model, these indices were the most significant predictors of HCM (P<0.001, P<0.027 and P<0.006, respectively). The combination of Cornell (RaVL+SV3>2.8 mV in men and>2.0 mV in women) with Lewis (RI+SIII−RIII−SI>1.7 mV) or Gubner–Ungerleider (RI+SIII>2.5 mV) indices displayed the highest net sensitivity (80.0% and 76.7%, respectively) while retaining excellent specificity (88.9% and 91.6%, respectively). In conclusion, the combination of the Cornell and the Lewis or Gubner voltage criteria showed the greatest net sensitivity and specificity for the LVH diagnosis of HCM in a cardiovascular examination conducted in young people.
Effects of socioeconomic status on the physical activity in adolescents: a systematic review of the evidence
Authors: Stalsberg R. , Pedersen A. V.
Published: February 2010

The relationship between physical activity and socioeconomic status (SES) is evident in the adult population, but is much discussed with regard to adolescents. The main objective of this review was, therefore, to clarify whether there is a relationship between physical activity and SES in adolescents. Computerized searches were conducted in the databases PubMed, ISI Web of knowledge and SPORTDiscus to identify all relevant articles up to July 2009. Other review articles, descriptive or theoretical articles and articles where the adolescents in the samples were outside the age group of 13–18 years were excluded. Sixty‐two articles were included in the end. The main results support the hypothesis that there is an association between SES and physical activity among adolescents, and that adolescents with higher SES are more physically active than those with lower SES. The findings are, however, far from uniform. Forty‐two percent of the included studies report no or an opposite relation. There is also an inconsistent use of measures for both variables that complicates explanations and interpretations of the findings. This fortifies the claim that there is no single explanation for a possible difference in physical activity between different socioeconomic groups.
Predictors of functional capacity and skill in youth soccer players
Authors: Figueiredo A. J. , Coelho e Silva M. J. , Malina R. M.
Published: February 2010

Predictors of functional capacities and skills in 143 soccer players aged 11–14 years from five clubs in Portugal were investigated. Data for players aged 11–12 (n=75) and 13–14 (n=68) years included chronological age, skeletal age, stage of pubic hair (PH), anthropometry, four functional capacities, four soccer skills and experience; composite functional and skill scores were derived. Multiple linear regression analysis was used to examine the independent effects of age, maturity, body size and proportions, adiposity and experience on individual functional capacities and skills and composite scores. Explained variances differed among functional capacities (22–48%) and skills (<25%), and were greater for composite functional (younger 37%, older 58%) than skill (younger 26%, older 18%) scores. Skeletal maturity was a predictor of the counter‐movement jump in both groups and of composite functional and skill scores in older players. Age and adiposity were primary predictors in players aged 11–12 years, while experience and a proportionally longer trunk (conversely, relatively shorter lower extremities) appeared among predictors in players aged 13–14 years. PH was not among predictors. Except for the counter‐movement jump, predictors of functional capacities and soccer skills differed between age groups.
Post‐exercise aortic hemodynamic responses to low‐intensity resistance exercise with and without vascular occlusion
Authors: Figueroa A. , Vicil F.
Published: February 2010

High‐intensity resistance exercise may acutely increase arterial stiffness. Vascular occlusion (VO) acutely decreases arterial stiffness. The purpose of this study was to evaluate acute aortic hemodynamic responses to low‐intensity resistance exercise (LIRE) with slow eccentric movement with and without VO. Twenty‐three young healthy subjects (12 women and 11 men) were randomized into three trials: seated control (CON), LIRE (six sets at 40% one repetition maximum), and LIRE with VO. Vascular measurements were assessed before, immediately (post1), and 30 min after (post30) each trial. There were significant (P<0.05) time effects and trial‐by‐time interactions such that the changes were greater after the LIRE trials compared with CON. Aortic blood pressure [systolic (∼10 mmHg) and diastolic (∼5 mmHg)], heart rate (∼23 b.p.m.), and the first (∼10 mmHg) and second systolic peak (∼9 mmHg) increased, whereas time to reflection decreased (∼15 ms) at post1. All measurements returned to baseline at post30, except aortic augmentation index (AIx), which decreased ∼5% after the LIRE trials compared with CON. Increases in cardiovascular variables immediately after the LIRE trials were mild and short lasting. Our results indicate that LIRE acutely decreases AIx 30 min after exercise cessation. The use of moderate intermittent VO during LIRE does not produce additional post‐exercise vascular effects.
Effects of Darbepoetin Alfa with exercise in cancer patients undergoing chemotherapy: an explorative study
Authors: Rørth M. , Madsen K. R. , Burmølle S. H. , Midtgaard J. , Andersen C. , Nielsen B. , Stage M. , Adamsen L.
Published: February 2010

Fatigue is frequent in cancer patients undergoing chemotherapy. Erythropoietins (EPO) have shown well‐documented effects on these patients, and administered in pharmacological doses, may reduce the need for transfusion of blood cells and improve quality of life (QoL). An explorative, descriptive, non‐randomised intervention study using semi‐structured interviews was conducted with the aim to gain an insight into the effects and experiences associated with EPO treatment in combination with a structured 6‐week physical exercise intervention. Sixteen cancer patients with evidence of disease, who had received at least one cycle chemotherapy, participated. Participants received 500 μg Darbepoetin Alfa (DA) every 3 weeks during the intervention. Four typologies of patients were identified with regard to DA effects. The interviews revealed that eleven patients experienced some kind of immediate improvement in cognitive and emotional functioning, and subjective daily well‐being. Furthermore physical improvement and changes in QoL outcomes showed no significant differences between the study group and a reference group. A significant increase in the hemoglobin concentration (7.14–7.87 mmol/L, P<0.05) was found in the study group. The future use of EPO in cancer patients is hampered by the reported negative influence of EPO on the prognosis in some diagnoses and should be based on randomized studies.
The KörperkoordinationsTest für Kinder: reference values and suitability for 6–12‐year‐old children in Flanders
Authors: Vandorpe B. , Vandendriessche J. , Lefevre J. , Pion J. , Vaeyens R. , Matthys S. , Philippaerts R. , Lenoir M.
Published: February 2010

An adequate coordination level in children is important for their general development, but also for health, psychosocial, academic and well‐being‐related reasons. In this study, the suitability of the KörperkoordinationsTest für Kinder (KTK) as an assessment instrument for the gross motor coordination was evaluated in 2470 children from 26 elementary schools for general education spread over the Flemish and Brussels‐capital region. All children performed four subtests: walking backwards (WB), moving sideways (MS), hopping for height (HH) and jumping sideways (JS). Age and gender‐specific values were established for the Flemish children anno 2008. Overall, the current sample scored significantly worse than their 1974 German counterparts (P<0.001). Score distribution showed 21% of the children being placed in the problematic range of gross motor coordination level. A decline in coordination was observed especially in those tasks relying primarily on coordinative capacities (WB and MS), while improvements or status quo in those tasks relying on strength and speed (JS and HH) were explained by secular trends. We suggest that the KTK is a valuable instrument for the assessment of the gross motor coordination of Flemish children and efforts should be made in order to face the decline in coordination.
Physical self‐perception and motor performance in normal‐weight, overweight and obese children
Authors: Morano M. , Colella D. , Robazza C. , Bortoli L. , Capranica L.
Published: February 2010

The aim of this study was to examine the relationships among physical self‐perception, body image and motor performance in Italian middle school students. Two hundred and sixty children were categorized into normal‐weight (n=103), overweight (n=86) or obese (n=71) groups. Perceived coordination, body fat and sports competence were assessed using the Physical Self‐Description Questionnaire, while body image was measured using Collins' Child Figure Drawings. Individuals' perceptions of strength, speed and agility were assessed using the Perceived Physical Ability Scale. Tests involving the standing long jump, 2 kg medicine‐ball throw, 10 × 5 m shuttle‐run and 20 and 30 m sprints were also administered. Girls, when compared with boys, and overweight and obese participants, when compared with normal‐weight peers, reported lower perceived and actual physical competence, higher perceived body fat and greater body dissatisfaction. Body dissatisfaction mediated all the associations between body mass index (BMI) and the different aspects of physical self‐perception in boys, but not in girls. The same pattern of results was found for physical self‐perception as a mediator of the relationship between BMI and body dissatisfaction. In conclusion, obesity proved to have adverse effects on both motor performance and physical self‐perception.
Isolated hip and ankle fatigue are unlikely risk factors for anterior cruciate ligament injury
Authors: Thomas A. C. , Palmieri‐Smith R. M. , McLean S. G.
Published: February 2010

Lower extremity neuromuscular fatigue purportedly increases anterior cruciate ligament (ACL) injury risk through promotion of extreme landing mechanics. However, the impact of fatigue on muscle groups critical to the landing strategy remains unclear. This study examined the effects of isolated hip rotator and triceps surae fatigue on lower extremity landing biomechanics. Sixteen healthy females (18–22 years) reported for testing on two occasions, with one muscle group fatigued per session. Subjects performed three single‐leg landings onto a force platform pre‐ and post‐fatigue, defined as an 80% decrease in peak torque in the targeted muscle group. Hip rotator fatigue was induced via alternating concentric contractions and triceps surae fatigue through concentric plantar flexion contractions on an isokinetic dynamometer. Initial contact (IC) kinematics and peak stance (PS) kinetics and kinematics were analyzed pre‐ and post‐fatigue. Hip rotator fatigue increased IC (P=0.05) and PS (P=0.04) hip internal rotation angles. Triceps surae fatigue decreased IC knee flexion (P=0.01) angle. Isolated hip rotator and triceps surae fatigue each produced modifications in lower limb kinematic parameters viewed as risk factors for ACL injury. These modifications, however, do not appear of sufficient magnitude to compromise ligament integrity, suggesting injury via an integrative lower extremity fatigue mechanism is more likely.
Dentinogenic potential of the dental pulp: facts and hypotheses
Authors: TZIAFAS DIMITRIOS
Published: February 2010

The aim of the present article is to discuss observations and hypotheses from different experimental approaches on the biological mechanisms underlying initiation of tertiary dentin formation and therapeutic control of pulp–dentinal regeneration. The specific dentinogenic potential of dental pulp cells in up‐regulating the biosynthetic activity of primary odontoblasts (reactionary dentinogenesis) and differentiation into odontoblast‐like cells (reparative dentinogenesis) is described. The role of biologically active matrices and molecules as signaling factors in the expression of the dentinogenic potential of dental pulp cells, in numerous ex vivo and in vivo models, is reviewed. Data are focused on the mechanisms by which the signaling molecules, in the presence of the appropriate pulp microenvironment and specific mechanical support, can induce competent pulpal cells in the acquisition of odontoblast‐like cell phenotype and reparative dentin formation. The ability of tissue engineering to stimulate reconstruction of the amputated pulp–dentin complex offers exciting opportunities for the future. Advances in molecular biology and bioengineering research might thus be integrated into the clinical problems of endodontology. Received 13 February 2009; accepted 2 September 2009.
Cognitive outcome at 2 years of age in Finnish infants with very low birth weight born between 2001 and 2006
Authors: Munck P , Haataja L , Maunu J , Parkkola R , Rikalainen H , Lapinleimu H , Lehtonen L ,   the PIPARI Study Group
Published: February 2010

Aim:  To study cognitive outcome of premature, very low birth weight (VLBW) infants in relation to parental education and neonatal data.

Methods:  A regional cohort of 182 VLBW infants born between 2001 and 2006 was followed up. Brain ultrasounds (US) were examined serially until term age and brain magnetic resonance imaging at term age. Neurological status was examined systematically. Cognitive development was assessed using the Mental Developmental Index (MDI) of Bayley Scales at 2 years of corrected age. A total of 192 healthy full‐term (FT) controls were assessed with the MDI at 2 years of age.

Results:  The mean MDI in VLBW infants was 101.7 (SD 15.4), which was lower compared with FT controls (109.8, SD 11.7, p < 0.001). In regression analysis of the demographic and medical data of VLBW infants, postnatal corticosteroids (p = 0.04), intestinal perforation (p = 0.03) and major brain pathology (p = 0.02) were negatively associated with the MDI. In VLBW infants, the prevalence of neurodevelopmental impairment was 9.9% (3.3% MDI below 70, 7.1% cerebral palsy, 2.2% hearing aid, no blind infants).

Conclusion:  Cognitive development of VLBW infants seemed to have improved in comparison with earlier publications, but it differed from the FT controls. Neonatal factors affected cognitive development. Therefore, updated regional follow‐up data are important for clinicians.
Vitamin D status and acute lower respiratory infection in early childhood in Sylhet, Bangladesh
Authors: Roth DE , Shah R , Black RE , Baqui AH
Published: February 2010

Aim: Acute lower respiratory tract infection (ALRI) is the most important global cause of childhood death. Micronutrient deficiencies may increase the risk of ALRI. A case–control study was conducted to assess the association between vitamin D status and ALRI in rural Bangladesh.

Methods: Children aged 1–18 months hospitalized with ALRI (cases) were individually matched to controls on age, sex, and village (N = 25 pairs). The mean serum 25‐hydroxyvitamin D concentration [25(OH)D] in cases and controls was compared using paired t‐test. The unadjusted and adjusted odds of ALRI were assessed by multivariate conditional logistic regression.

Results: Mean [25(OH)D] was significantly lower among ALRI cases than controls (29.1 nmol/L vs. 39.1 nmol/L; p = 0.015). The unadjusted odds of ALRI was halved for each 10 nmol/L increase in [25(OH)D] (OR 0.53, 95% CI 0.30–0.96). Adjustment for confounders increased the magnitude of the association.

Conclusion: Vitamin D status was associated with early childhood ALRI in a matched case–control study in rural Bangladesh. Randomized trials may establish whether interventions to improve vitamin D status can reduce the burden of ALRI in early childhood.
Breastfeeding perceptions in communities in Mangochi district in Malawi
Authors: Kamudoni PR , Maleta K , Shi Z , De Paoli MM , Holmboe‐Ottesen G
Published: February 2010

Aim:  To investigate mothers’ perceptions of breastfeeding and influences from their social network.

Methods:  A cross‐sectional survey was carried out in Mangochi district, Malawi where questionnaire data from 157 rural and 192 semi‐urban mother–infant pairs were obtained.

Results:  The proportion of mothers who thought that exclusive breastfeeding should last for 6 months and those who reported to have actually exclusively breastfed were 40.1% and 7.5% respectively. Of those who reported practising exclusive breastfeeding for 6 months, 77.5% stated that exclusive breastfeeding should last for 6 months. This opinion was independently associated with giving birth in a Baby‐Friendly facility, OR = 5.22; 95% CI (1.92–14.16). Among the mothers who thought that exclusive breastfeeding should last for less than 6 months, 43.9% reported having been influenced in their opinion by health workers. Infant crying was the most common (62.4%) reason for stopping exclusive breastfeeding.

Conclusion:  The findings illustrate the positive impact health workers can have, as well as the need to raise awareness of the benefits of exclusive breastfeeding among both health workers and mothers. Furthermore, continued counselling of mothers on how to deal with stressful infant behaviour such as crying may assist to prolong exclusive breastfeeding.
Identifying problematic severe asthma in the individual child – does lung function matter?*
Authors: Lang AM , Konradsen J , Carlsen K‐H , Sachs‐Olsen C , Mowinckel P , Hedlin G , Lødrup Carlsen KC
Published: February 2010

Aim:  Measures of lung function (usually FEV1 <80% predicted) are used to classify asthma severity in both adults and children, despite evidence that lung function impairment is less pronounced in the paediatric asthma population. The present study assesses the relevance of lung function measurements as discriminators of severe childhood asthma.

Methods:  Fifty‐one school‐aged children with problematic severe asthma, 37 mild‐to‐moderate asthmatics and 29 healthy controls underwent a comprehensive clinical work‐up. Problematic severe asthma was defined in patients exhibiting poor asthma control despite high‐dose inhaled corticosteroid treatment and at least one other asthma controller drug. Mild‐to‐moderate asthmatic children used low‐dose inhaled steroids and reported minimal asthma symptoms.

Results:  Baseline FEV1 values were significantly reduced in children with problematic severe asthma, yet FEV1 <80% predicted showed a low sensitivity (41%) for discriminating severe vs. mild‐to‐moderate asthma. Receiver‐operated characteristic analysis estimated the optimal cut‐off of FEV1 to be 90% predicted in this population (sensitivity 61%, specificity 83%). Baseline FEV1/FVC and FEF25–75 values were not superior to FEV1 in discriminating problematic severe asthma, and neither exhaled nitric oxide levels nor bronchial hyperresponsiveness differentiated between the two asthmatic study populations.

Conclusion:  Spirometric measurements are insensitive discriminators of problematic severe asthma in childhood.
The effect of ascorbate on minor recurrent aphthous stomatitis
Authors: Yasui K , Kurata T , Yashiro M , Tsuge M , Ohtsuki S , Morishima T
Published: February 2010

Aim:  Minor recurrent aphthous stomatitis (MRAS) is a common, painful and inflammatory ailment of the oral cavity with juvenile onset and unknown aetiology. The purpose of this study was to evaluate the potential of ascorbate (vitamin C) to reduce the frequency of MRAS and severity of pain.

Patients and methods:  Sixteen MRAS patients (9 boys and 7 girls: mean age, 12.0 ± 2.4 years old) were assigned to take an oral dosage of 2000 mg/m2/day ascorbate.

Subjects:  Their baseline frequency of outbreaks and the level of pains were compared during the treatment; in addition, a crossover clinical trial was performed. Polymorphonuclear leucocytes play a role in the pathogenesis, and then superoxide anion production was evaluated in prior to ascorbate treatment.

Results:  The data indicated a statistically significant 50% reduction in oral ulcer outbreaks and a decline of pain level. Neutrophils were primed for superoxide anion production in the patients with MRAS.

Conclusion:  Ascorbate may modulate the generation of reactive oxygen species and augment neutrophil apoptosis, which could prevent neutrophil‐mediated inflammation. Ascorbate seems to be effective, but the findings of our study were preliminary and it should be re‐evaluated with a larger randomized controlled clinical trials.
Interleukin‐4 receptor polymorphisms in asthma and allergy: relation to different disease phenotypes
Authors: Hesselmar B , Bergin A‐M , Park H , Hahn‐Zoric M , Eriksson B , Hanson L‐Å , Padyukov L
Published: February 2010

Aim:  Inheritance and genetic factors are supposed to influence susceptibility to asthma and allergy. We tested if single nucleotide polymorphisms (SNPs) in the IL4R gene were associated with susceptibility to such diseases, or if they were related to the phenotypic presentation of asthma and allergic rhinoconjunctivitis (ARC).

Methods:  Three hundred and nine 12‐ to 13‐year‐old children were included. Six SNPs in the IL4R were analysed in response to current allergic disease, and to presentation of specific asthma and ARC phenotypes. Questionnaires were used to determine allergic disease status, and skin prick tests to evaluate sensitization to common airborne allergens.

Results:  Less eczema was seen in individuals with the AA‐genotype of rs2057768, and less ARC among those with the AA‐genotype of rs2107356, especially ARC associated with sensitization to pollen. The AA‐genotype of rs2057768 and the TT genotype of rs3024632 were associated with a specific asthma phenotype.

Conclusion:  Variations within the IL4R gene are associated with allergic diseases in children, preferably with eczema and disease phenotypes of ARC and asthma.
Complications affecting preterm neonates from 1991 to 2006: what have we gained?
Authors: Groenendaal F , Termote JUM , Van Der Heide‐Jalving M , Van Haastert IC , De Vries LS
Published: February 2010

Aim:  In this study, we determined whether outcome of preterm neonates has improved over a period of 16 years.

Study design:  Inborn neonates with a gestational age of 25.0–29.9 weeks were included. Patients with severe congenital malformations were excluded. Mortality and morbidity (chronic lung disease; CLD, intraventricular haemorrhage: IVH grade III or IV, cystic periventricular leukomalacia: cPVL, perforated necrotizing enterocolitis: NEC, severe retinopathy of prematurity needing surgery: ROP and cerebral palsy: CP) were compared in three periods (period 1: 1991–1996 n = 434; period 2: 1997–2001 n = 356; period 3: 2002–2006 n = 422).

Results:  Infant mortality decreased from 15.2% to 10.9%. CLD did not differ significantly between periods (14.1–14.8%). Perforated NEC decreased from 2.8% to 1.6%. IVH grade III and IV both remained at 5.7% in period 3, whereas cPVL decreased significantly from 4.5% to 1.6%. Cerebral palsy decreased from 5.8% to 3.5% in period 3. Two neonates in each period were in need of surgery for ROP.

Conclusion:  Inborn preterm patients showed an improved survival and a significant reduction in cPVL and CP. Perforated NEC showed a trend to decrease. CLD and IVH grade III and IV remain a matter of concern.
Snail associates with EGR‐1 and SP‐1 to upregulate transcriptional activation of p15INK4b
Authors: Hu Chi‐Tan , Chang Tsu‐Yao , Cheng Chuan‐Chu , Liu Chun‐Shan , Wu Jia‐Ru , Li Ming‐Che , Wu Wen‐Sheng
Published: February 2010

Snail is a multifunctional transcriptional factor that has been described as a repressor in many different contexts. It is also proposed as an activator in a few cases relevant to tumor progression and cell‐cycle arrest. This study investigated the detailed mechanisms by which Snail upregulates gene expression of the CDK inhibitor p15INK4b in HepG2 induced by the tumor promoter tetradecanoyl phorbol acetate (TPA). Using deletion mapping, the TPA‐responsive element on the p15INK4b promoter was located between 77 and 228 bp upstream of the transcriptional initiation site, within which the putative binding regions of early growth response gene 1 (EGR‐1) and stimulatory protein 1 (SP‐1) were found. Gene expression of EGR‐1, Snail and SP‐1 can be induced by TPA within 0.5–6 h. In addition, basal levels of SP‐1, but not of the other two transcriptional factors, were observed. Blockade of TPA‐induced gene expression of Snail, EGR‐1 or SP‐1 suppressed activation of the p15–pro228 reporter plasmid harboring the TPA‐responsive element. More detailed deletion mapping and site‐directed mutagenesis further concluded that the overlapping EGR‐1/SP‐1‐binding site was required for TPA‐induced p15–pro228 activation. In an EMSA, a DNA–protein complex was elevated by TPA, which can be blocked by antibodies against EGR‐1, SP‐1 or Snail at 6 h. Immunoprecipitation/western blotting demonstrated that TPA could trigger the association of EGR‐1 with Snail or SP‐1. Furthermore, a double chromatin immunoprecipitation assay verified that EGR‐1 could form a complex with Snail or SP‐1 on the TPA‐responsive element after treatment with TPA for 2–6 h. Finally, we demonstrated a novel Snail‐target region which could be bound by Snail and was also required for TPA‐induced p15–pro228 activation. In conclusion, Snail associates with EGR‐1 and SP‐1 to mediate TPA‐induced transcriptional upregulation of p15INK4b in HepG2.

Structured digital abstract

MINT‐7384899: Snail (uniprotkb:O95863) physically interacts (MI:0915) with EGR‐1 (uniprotkb:P18146) by anti bait coimmunoprecipitation (MI:0006)

MINT‐7384908: SP‐1 (uniprotkb:P08047) physically interacts (MI:0915) with EGR‐1 (uniprotkb:P18146) by anti bait coimmunoprecipitation (MI:0006)
Physiological truncation and domain organization of a novel uracil‐DNA‐degrading factor
Authors: Pukáncsik Mária , Békési Angéla , Klement Éva , Hunyadi‐Gulyás Éva , Medzihradszky Katalin F. , Kosinski Jan , Bujnicki Janusz M. , Alfonso Carlos , Rivas Germán , Vértessy Beáta G.
Published: February 2010

Uracil in DNA is usually considered to be an error, but it may be used for signaling in Drosophila development via recognition by a novel uracil‐DNA‐degrading factor (UDE) [(Bekesi A et al. (2007) Biochem Biophys Res Commun355, 643–648]. The UDE protein has no detectable similarity to any other uracil‐DNA‐binding factors, and has no structurally or functionally described homologs. Here, a combination of theoretical and experimental analyses reveals the domain organization and DNA‐binding pattern of UDE. Sequence alignments and limited proteolysis with different proteases show extensive protection by DNA at the N‐terminal duplicated conserved motif 1A/1B segment, and a well‐folded domain within the C‐terminal half encompassing conserved motifs 2–4. Theoretical structure prediction suggests that motifs 1A and 1B fold as similar α‐helical bundles, and reveals two conserved positively charged surface patches that may bind DNA. CD spectroscopy also supports the presence of α‐helices in UDE. Full functionality of a physiologically occurring truncated isoform in Tribolium castaneum lacking one copy of the N‐terminal conserved motif 1 is revealed by activity assays of a representative truncated construct of Drosophila melanogaster UDE. Gel filtration and analytical ultracentrifugation results, together with analysis of predicted structural models, suggest a possible dimerization mechanism for preserving functionality of the truncated isoform.

Structured digital abstract

MINT‐7385914: UDE (uniprotkb:Q961C4) and UDE (uniprotkb:Q961C4) bind (MI:0407) by cosedimentation in solution (MI:0028)
Stars quenching stars: how photoionization by local sources regulates gas cooling and galaxy formation
Authors: Cantalupo Sebastiano
Published: February 2010

Current models of galaxy formation lack an efficient and physically constrained mechanism to regulate star formation (SF) in low and intermediate mass galaxies. We argue that the missing ingredient could be the effect of photoionization by local sources on the gas cooling. We show that the soft X-ray and EUV flux generated by SF is able to efficiently remove the main coolants (e.g. He+, O4+ and Fe8+) from the halo gas via direct photoionization. As a consequence, the cooling and accretion time of the gas surrounding star-forming galaxies may increase by one or two orders of magnitude. For a given halo mass and redshift, the effect is directly related to the value of the star formation rate (SFR). Our results suggest that the existence of a critical SFR above which ‘cold’ mode accretion is stopped, even for haloes with Mvir well below the critical shock-heating mass suggested by previous studies. The evolution of the critical SFR with redshift, for a given halo mass, resembles the respective steep evolution of the observed SFR for z < 1. This suggests that photoionization by local sources would be able to regulate gas accretion and SF, without the need for additional, strong feedback processes.
Superflares from magnetars revealing the GRB central engine
Authors: Giannios Dimitrios
Published: February 2010

Long-duration gamma-ray bursts (GRBs) may be powered by the rotational energy of a millisecond magnetar. I argue that the GRB-driving magnetars lie at the high end of the distribution of magnetic field strengths of magnetars. The field of GRB magnetars decays on time-scale of hundreds of years and can power soft gamma-ray repeater (SGR)-like flares up to ∼100 times more powerful than the 2004 event of SGR 1806–20. A few of these flares per year may have been observed by the Burst and Transient Source Experiment (BATSE) and classified as short-duration GRBs. Association of one of these superflares with a nearby dL≲ 250 Mpc galaxy and the discovery of a, coincident in space, 100-yr-old GRB afterglow (observed in the radio) will be the characteristic signature of the magnetar model for GRBs.
Mineralogy and crystallization history of the Ilafegh 009 EL‐chondritic impact melt rock: An ATEM investigation
Authors: LEROUX H. , DOUKHAN J. C. , BISCHOFF A.
Published: February 2010

Abstract— The Ilafegh 009 meteorite is an impact melt rock from an EL‐chondritic parent body. Its mineralogic assemblage is the result of rapid crystallization after shock‐induced melting. We report here an analytical transmission electron microscopy (ATEM) study of the major minerals of this meteorite (enstatite, plagioclase, Fe‐Ni metal and sulfides). Based on this study, we discuss the crystallization sequence and the further evolution of the rock in the solid state.

Microstructure and microanalyses confirm that the mineralogy of Ilafegh 009 results from the crystallization of an EL‐chondritic melt. The high compositional variability of plagioclases and the presence of silica‐rich glass pockets indicate fast cooling. During crystallization, the large enstatite grains trapped a large number of phases (plagioclase, silica‐rich glass and enstatite nuclei). Sulfides (troilite, alabandite and daubreelite) form finely polycrystalline areas and reveal a complex crystallization sequence. Although Fe‐Ni metal grains formed during rapid cooling, their microstructures show that some postsolidification process occurred in Ilafegh 009. A large number of tiny Ni‐P‐Si‐rich precipitates were detected that formed as a result of exsolution of elements that become insoluble in kamacite at low temperature.

Finally, the microstructure (dislocation arrangements and phase transformations) observed in enstatite and Fe‐Ni metal attests that Ilafegh 009 also experienced a moderate postsolidification shock event.
Absorption bands near three micrometers in diffuse reflectance spectra of carbonaceous chondrites: Comparison with asteroids
Authors: SATO Kimiyasu , MIYAMOTO Masamichi , ZOLENSKY Michael E.
Published: February 2010

Abstract— We measured infrared diffuse reflectance spectra of several carbonaceous chondrites in order to obtain additional information on the surface materials of their presumed parent bodies, C‐type asteroids. The presence and intensity of absorption bands near 3 μm in the reflectance spectra are due to the presence and abundance of hydrates and/or hydroxyl ions. The absorption features of the 3 μm hydration bands of carbonaceous chondrites were compared with those of asteroids 1 Ceres and 2 Pallas. They are commonly classified into separate subtypes, G‐ and B‐type. The spectral shapes of Pallas and Renazzo (CR2 chondrite) around the 3 μm absorption band are an excellent match. This result may suggest that the amount of hydrous minerals in the surface material of Pallas is smaller than that in the CM2 or CI chondrites, and the hydrous minerals on the surface of Pallas may be similar to those found in Renazzo. The spectral features around the 3 μm band of Ceres are different from those of carbonaceous chondrites studied in this paper.
A chondrule origin for dusty relict olivine in unequilibrated chondrites
Authors: JONES RHIAN H. , DANIELSON LISA R.
Published: February 2010

Abstract—We address the origin of “dusty,” metal‐bearing relict olivine grains in chondrules. It has been suggested previously that these grains may be either primitive condensates or derived from a previous generation of chondrules. In this paper, we infer the original composition of dusty olivine grains, before they were reduced, and examine the possibility that they were derived from a previous generation of chondrules. Original compositions of dusty grains, including their estimated initial FeO contents and their minor element contents, match closely with compositions of olivines from chondrules in unequilibrated chondrites. In addition, the cores of some dusty grains are unaltered, and the compositions of these cores are also consistent with a chondrule origin. Therefore, we conclude that a derivation from a previous generation of chondrules is a plausible origin for these relicts. Although alternative origins, such as condensates or interstellar grains, cannot be ruled out on the basis of the available data, chondrules are an obvious source, and we suggest that this is the most likely interpretation. If this is the case, it is additional evidence for the importance of recycling of chondrule material in the chondrule‐forming region.
Lewis Cliff 86360: An Antarctic L‐chondrite with a terrestrial age of 2.35 million years
Authors: WELTEN K. C. , ALDERLIESTEN C. , VAN DER BORG K. , LINDNER L. , LOEKEN T. , SCHULTZ L.
Published: February 2010

Abstract— We measured the concentrations of the cosmogenic radionuclides 10Be (half‐life = 1.51 × 106 a), 26Al (7.05 × 105 a) and 36Cl (3.01 × 105 a) in Lewis Cliff (LEW) 86360, an L‐chondrite from the Lewis Cliff stranding area, East Antarctica. In addition, the concentrations and isotopic compositions of He, Ne and Ar were measured. The combined results yield a terrestrial age of 2.35 ± 0.15 Ma. Only one other stony meteorite with a similar terrestrial age (∼2 Ma) is known from the Allan Hills stranding area (ALH 88019), whereas all previously dated stony meteorites from Antarctica are younger than 1 Ma. We argue that LEW 86360 spent most of its terrestrial residence time deep inside the ice, near the base of the glacier, where ice flow rates are much lower than at the surface. The terrestrial ages of LEW 86360 and ALH 88019 are consistent with existing hypotheses concerning the stability and persistence of the East Antarctic ice sheet.
Cosmogenic effects in Mbale, L5/6 chondrite
Authors: MURTY S. V. S. , BHANDARI N. , SUTHAR K. M. , CLEMENT C. J. , BONINO G. , CASTAGNOLI G. CINI
Published: February 2010

Abstract— Measurements of particle tracks, cosmogenic radionuclides, and rare gas isotopes in Mbale indicate that the meteoroid had a simple, one‐stage exposure for 30.2 Ma in interplanetary space. On the basis of the measured track production rates and 60Co and 26Al activities, the meteoroid is estimated to be a sphere with a radius of ∼36 cm. The activities of several cosmogenic radionuclides (i.e., 57Co, 54Mn, 22Na, 44Ti, and 26Al) in two fragments having different shielding, as estimated by their track density and 60Co activity, provide the depth variation in their production rates. Cobalt‐57, 54Mn and 22Na activities agree with the production that is expected around the maximum of the solar cycle 22 as calculated from the Sunspot numbers. The U, Th‐4He and K‐40Ar ages are measured to be 0.54 Ga indicating a late thermal event which is in agreement with the thermal history of some other L group chondrites. The trapped N has δ15N of −57 ± 4%o, which is much lighter than the average L‐group chondrite value; this indicates the presence of an isotopically anomalous light N component.
The Guenie and Gao chondrites from Burkina Faso: Probably a single shower of stones
Authors: BOUROT‐DENISE Michèle , WENMENGA Urbain , CHRISTOPHE Mireille
Published: February 2010

Abstract— Two H4–5 meteorite showers have been reported to have fallen at one month intervals in the Guenie‐Gao area, but eyewitness accounts are imprecise. Though subtle mineralogical differences are found between stones with different 21Ne content, these differences are insufficient to confirm that two meteorite falls had occurred.
Weathering and polymerization of tektites: An x‐ray photoelectron spectroscopy (XPS) investigation
Authors: BIINO GIUSEPPE G. , GRÖNING PIERANGELO , MEISEL THOMAS
Published: February 2010

Abstract— Tektites are natural glasses formed from terrestrial material that was melted and displaced by the impact of an extraterrestrial body. The surface and near‐surface compositions of tektite glass results from fractionation during impact and ejection, and/or postsolidification weathering. The first goal of this study was to characterise the surface and near‐surface (in the order of tens of angstroms) chemical composition of two tektites by x‐ray photoelectron spectroscopy (XPS), and to estimate the importance of weathering vs. fractionation during flying. In order to separate the chemical modification due to weathering from that due to fractionation during ballistic flight, we studied two samples from the Australasian tektite strewn field. One of them was collected in a hot desert area (Nullarbor Plain, Australia) and the other, in a humid climate (Thailand). Our study reveals the presence of well‐developed leached layers in both tektites. In the Australian tektite, Si is depleted in the topmost layers (a few tens of angstroms). A more complex chemical zoning is defined in the tektite from Thailand. These leached layers are comparable to those observed in weathered glasses, and therefore we conclude that weathering is responsible for the chemical composition of the surface and near‐surface compositions. The second goal was to investigate the chemical environment of O, N and C in the glass. The O peak was resolved into two bridging O components (Si‐O‐Si and Al‐O‐Si) that are comparable to O environments in artificial glasses. The binding energy of the C1s electron is typical for C‐C and C‐H bonds in hydrocarbons; minor organic acid components are also present. Nitrogen is only observed on the surface of the Thailand tektite. The binding energy of N1s is comparable to that of ammonia, and the surface enrichment in N is interpreted as due to sorption related to interactions between glass and fluid buffered by the organic material in the soil.
Shock‐induced melting and vaporization of shatter cone surfaces: Evidence from the Sudbury impact structure
Authors: GIBSON HEATHER M. , SPRAY JOHN G.
Published: February 2010

Abstract— Analytical scanning electron microscopy has been used to investigate the surface textures and compositions of newly exposed shatter cones from the 1.85 Ga Sudbury impact structure, Canada. Unusual surface microstructures are observed at the micron scale, including silicate melt smears, melt fibres and melt splats. Silicate and Ni‐rich spherules up to 5 μm in diameter adorn earlier‐formed surface features, and we interpret these to be condensates formed due to shock‐induced vaporization of the shatter cone surfaces. The development of striations on the shatter cones is attributed to shock‐related fracture and slip. Formation of melts and spherules indicates that the highest ranks of shock metamorphism (Stages IV and V) were realized, but only on a very localized scale. Shatter cone surfaces are, therefore, likely sites for the development of high‐pressure polymorphs and, if the chemistry is appropriate, fullerenes. As such, they may be equivalent to “Type A” pseudotachylytes and shock veins in meteorites.
Petrographic and mineralogical study of new EH melt rocks and a new enstatite chondrite grouplet
Authors: LIN Y. , KIMURA M.
Published: February 2010

Abstract— Enstatite chondrites are classified into EH and EL groups, and some of them were melted once. In this paper, we report petrography and mineral chemistry of five new Antarctic enstatite chondrites. Yamato 793225 is characterized by intermediate properties between the EH and EL groups and probably represents a new grouplet of enstatite chondrites. The three paired meteorites (Y‐8404, Y‐8414 and Y‐86004) may have cooled rapidly near the surface of the parent body as impact EH melt rocks. Yamato 82189 is also classified as EH melt rock, but it experienced slow cooling as did Y‐793225. Yamato 82189 contains the first occurrence of phlogopite in enstatite meteorites.
Bulk and stable isotopic compositions of carbonate minerals in Martian meteorite Allan Hills 84001: No proof of high formation temperature
Authors: TREIMAN ALLAN H. , ROMANEK CHRISTOPHER S.
Published: February 2010

Abstract— Understanding the origin of carbonate minerals in the Martian meteorite Allan Hills (ALH) 84001 is crucial to evaluating the hypothesis that they contain traces of ancient Martian life. Using arguments based on chemical equilibria among carbonates and fluids, an origin at >650 °C (inimical to life) has been proposed. However, the bulk and stable isotopic compositions of the carbonate minerals are open to multiple interpretations and so lend no particular support to a high‐temperature origin. Other methods (possibly less direct) will have to be used to determine the formation temperature of the carbonates in ALH 84001.
The history of Allan Hills 84001 revised: Multiple shock events
Authors: TREIMAN ALLAN H.
Published: February 2010

Abstract—The geologic history of Martian meteorite Allan Hills (ALH) 84001 is more complex than previously recognized, with evidence for four or five crater‐forming impacts onto Mars. This history of repeated deformation and shock metamorphism appears to weaken some arguments that have been offered for and against the hypothesis of ancient Martian life in ALH 84001. Allan Hills 84001 formed originally from basaltic magma. Its first impact event (I1) is inferred from the deformation (D1) that produced the granular‐textured bands (“crush zones”) that transect the original igneous fabric. Deformation D1 is characterized by intense shear and may represent excavation or rebound flow of rock beneath a large impact crater. An intense thermal metamorphism followed D1 and may be related to it. The next impact (I2) produced fractures, (Fr2) in which carbonate “pancakes” were deposited and produced feldspathic glass from some of the igneous feldspars and silica. After I2, carbonate pancakes and globules were deposited in Fr2 fractures and replaced feldspathic glass and possibly crystalline silicates. Next, feldspars, feldspathic glass, and possibly some carbonates were mobilized and melted in the third impact (I3). Microfaulting, intense fracturing, and shear are also associated with I3. In the fourth impact (I4), the rock was fractured and deformed without significant heating, which permitted remnant magnetization directions to vary across fracture surfaces. Finally, ALH 84001 was ejected from Mars in event I5, which could be identical to I4. This history of multiple impacts is consistent with the photogeology of the Martian highlands and may help resolve some apparent contradictions among recent results on ALH 84001. For example, the submicron rounded magnetite grains in the carbonate globules could be contemporaneous with carbonate deposition, whereas the elongate magnetite grains, epitaxial on carbonates, could be ascribed to vapor‐phase deposition during I3.
Epitaxial growth of nanophase magnetite in Martian meteorite Allan Hills 84001: Implications for biogenic mineralization
Authors: BRADLEY J. P. , MCSWEEN H. Y. , HARVEY R. P.
Published: February 2010

Abstract— Crystallographic relationships between magnetite, sulfides, and carbonate rosettes in fracture zones of the Allan Hills (ALH) 84001 Martian meteorite have been studied using analytical electron microscopy. We have focused on those magnetite grains whose growth mechanisms can be rigorously established from their crystallographic properties. Individual magnetite nanocrystals on the surfaces of carbonates are epitaxially intergrown with one another in “stacks” of single‐domain crystals. Other magnetite nanocrystals are epitaxially intergrown with the surfaces of the carbonate substrates. The observed magnetite/carbonate (hkl) Miller indices orientation relationships are (?, ?, 3)m ‖ (1, ?, 0)c and (1, ?, 1)m ‖ (0,0, 3)c with lattice mismatches of ∼13% and ∼11%, respectively. Epitaxy is a common mode of vapor‐phase growth of refractory oxides like magnetite, as is the spiral growth about axial screw dislocations previously observed in other magnetite nanocrystals in ALH 84001. Epitaxy rules out intracellular precipitation of these magnetites by (Martian) organisms, provides further evidence of the high‐temperature (>120 °C) inorganic origins of magnetite in ALH 84001, and indicates that the carbonates also have been exposed to elevated temperatures.
Chondrule precursor minerals as anhydrous phases
Authors: MAHARAJ SUSAN V. , HEWINS ROGER H.
Published: February 2010

Abstract— Chondrules might be generated from hydrous or anhydrous precursor minerals, but vesicles due to dehydration during melting are absent in natural chondrules. The occurrence of vesicles in experimental charges made from serpentine‐rich starting material that was (a) flash heated and remelted several times, (b) melted for long durations and (c) melted in a vacuum has been studied in order to test whether vesicles could be eliminated in chondrules made from hydrous precursors. High percentages of vesicles in all experiments indicate that chondrules, whether melted once, multiple times, for a brief or extended period, at solar nebula or higher pressure, were made from anhydrous phases.