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941.
Pauline Scherdel Jean-Fran?ois Salaün Marie-No?lle Robberecht-Riquet Laura Reali Gabriella Páll Elke J?ger-Roman Manuel Praena Crespo Marilena Moretto Margareta Seher-Zupan?i? Sigurlaug Agustsson the European Confederation of Primary Care Paediatricians research group Martin Chalumeau 《PloS one》2013,8(8)
Objective
We aimed to study current practices in growth monitoring by European primary care paediatricians and to explore their perceived needs in this field.Methods
We developed a cross-sectional, anonymous on-line survey and contacted primary care paediatricians listed in national directories in the 18 European countries with a confederation of primary care paediatricians. Paediatricians participated in the survey between April and September 2011.Results
Of the 1,198 paediatricians from 11 European countries (response rate 13%) who participated, 29% used the 2006 World Health Organization Multicentre Growth Reference Study growth charts, 69% used national growth charts; 61% used software to draw growth charts and 79% did not use a formal algorithm to detect abnormal growth on growth charts. Among the 21% of paediatricians who used algorithms, many used non-algorithmic simple thresholds for height and weight and none used the algorithms published in the international literature. In all, 69% of paediatricians declared that a validated algorithm to monitor growth would be useful in daily practice. We found important between-country variations.Conclusion
The varied growth-monitoring practices declared by primary care paediatricians reveals the need for standardization and evidence-based algorithms to define abnormal growth and the development of software that would use such algorithms. 相似文献942.
Xiaolu Qu Hua Zhang Yurong Xie Juan Wang Naizhi Chen Shanjin Huang 《The Plant cell》2013,25(5):1803-1817
Apical actin filaments are crucial for pollen tube tip growth. However, the specific dynamic changes and regulatory mechanisms associated with actin filaments in the apical region remain largely unknown. Here, we have investigated the quantitative dynamic parameters that underlie actin filament growth and disappearance in the apical regions of pollen tubes and identified villin as the major player that drives rapid turnover of actin filaments in this region. Downregulation of Arabidopsis thaliana VILLIN2 (VLN2) and VLN5 led to accumulation of actin filaments at the pollen tube apex. Careful analysis of single filament dynamics showed that the severing frequency significantly decreased, and the lifetime significantly increased in vln2 vln5 pollen tubes. These results indicate that villin-mediated severing is critical for turnover and departure of actin filaments originating in the apical region. Consequently, the construction of actin collars was affected in vln2 vln5 pollen tubes. In addition to the decrease in severing frequency, actin filaments also became wavy and buckled in the apical cytoplasm of vln2 vln5 pollen tubes. These results suggest that villin confers rigidity upon actin filaments. Furthermore, an observed decrease in skewness of actin filaments in the subapical region of vln2 vln5 pollen tubes suggests that villin-mediated bundling activity may also play a role in the construction of actin collars. Thus, our data suggest that villins promote actin turnover at pollen tube tips and facilitate the construction of actin collars. 相似文献
943.
Christian Milani Arancha Hevia Elena Foroni Sabrina Duranti Francesca Turroni Gabriele Andrea Lugli Borja Sanchez Rebeca Martín Miguel Gueimonde Douwe van Sinderen Abelardo Margolles Marco Ventura 《PloS one》2013,8(7)
Assessing the distribution of 16S rRNA gene sequences within a biological sample represents the current state-of-the-art for determination of human gut microbiota composition. Advances in dissecting the microbial biodiversity of this ecosystem have very much been dependent on the development of novel high-throughput DNA sequencing technologies, like the Ion Torrent. However, the precise representation of this bacterial community may be affected by the protocols used for DNA extraction as well as by the PCR primers employed in the amplification reaction. Here, we describe an optimized protocol for 16S rRNA gene-based profiling of the fecal microbiota. 相似文献
944.
Fabiano Tófoli de Araújo Victor M. Bolanos-Garcia Cristiane T. Pereira Mario Sanches Elisa E. Oshiro Rita C. C. Ferreira Dimitri Y. Chigardze Jo?o Alexandre Gon?alves Barbosa Luís Carlos de Souza Ferreira Celso E. Benedetti Tom L. Blundell Andrea Balan 《PloS one》2013,8(11)
Background
The uptake of sulphur-containing compounds plays a pivotal role in the physiology of bacteria that live in aerobic soils where organosulfur compounds such as sulphonates and sulphate esters represent more than 95% of the available sulphur. Until now, no information has been available on the uptake of sulphonates by bacterial plant pathogens, particularly those of the Xanthomonas genus, which encompasses several pathogenic species. In the present study, we characterised the alkanesulphonate uptake system (Ssu) of Xanthomonas axonopodis pv. citri 306 strain (X. citri), the etiological agent of citrus canker.Methodology/Principal Findings
A single operon-like gene cluster (ssuEDACB) that encodes both the sulphur uptake system and enzymes involved in desulphurisation was detected in the genomes of X. citri and of the closely related species. We characterised X. citri SsuA protein, a periplasmic alkanesulphonate-binding protein that, together with SsuC and SsuB, defines the alkanesulphonate uptake system. The crystal structure of SsuA bound to MOPS, MES and HEPES, which is herein described for the first time, provides evidence for the importance of a conserved dipole in sulphate group coordination, identifies specific amino acids interacting with the sulphate group and shows the presence of a rather large binding pocket that explains the rather wide range of molecules recognised by the protein. Isolation of an isogenic ssuA-knockout derivative of the X. citri 306 strain showed that disruption of alkanesulphonate uptake affects both xanthan gum production and generation of canker lesions in sweet orange leaves.Conclusions/Significance
The present study unravels unique structural and functional features of the X. citri SsuA protein and provides the first experimental evidence that an ABC uptake system affects the virulence of this phytopathogen. 相似文献945.
Adela Poitevin-Chacón José Hinojosa-Gómez 《Reports of Practical Oncology and Radiotherapy》2013,18(2):57-60
Aim
This survey is performed to learn about the structure of radiotherapy in México.Background
Radiation oncology practice is increasing because of the higher incidence of cancer. There is no published data about radiotherapy in México.Materials and methods
A questionnaire was sent to the 83 registered centers in the database of the Mexican regulatory agency. One out of the 32 states has no radiotherapy. 27 centers from 14 states provided their answers.Results
829 patients are treated annually with any radiotherapy modality in each center. Two centers have one cobalt machine, 7 have a cobalt and a linac and 10 have more than one linac. Five centers use 2D planning systems, 22 use 3D; 9, conventional simulators; 22, CT based simulation, and 1 center has no simulation. Most of the centers verify beams with films, electronic portal image devices and cone beam CTs are also used. Intensity modulated and image guided radiotherapy are performed in 5 states. Breast, prostate, cervix, lung, rectum and head and neck cancer are the six most common locations. There are 45 public and 38 private centers, 2 dedicated to children. Two gamma knife units, 5 Novalis systems, 1 tomotherapy and 2 cyberknife machines are working. All centers have at least one radiation oncologist, one physicist and one radiotherapist.Conclusions
Definitive conclusions cannot be drawn from this limited feedback due to a low participation of centers. This survey about radiotherapy in Mexico shows the heterogeneity of equipment as well as medical and technical staff in the whole country. 相似文献946.
Peter Müller Karl-Rudolf Erlemann Karin Müller Juan J. Calvete Edda Töpfer-Petersen Kathleen Marienfeld A. Herrmann 《European biophysics journal : EBJ》1998,27(1):33-41
PDC-109 is the major protein of bovine seminal plasma. It binds to the bovine sperm surface at ejaculation and modulates
sperm capacitation. PDC-109 displays phosphorylcholine- and heparin-binding activities which are thought to account for its
sperm surface coating and glycosaminoglycan-induced sperm capacitating activities, respectively. We have characterized the
interaction of isolated PDC-109 with membranes of phospholipid vesicles using a biophysical approach. Our results show that
PDC-109 interacts not only with the solvent-exposed phosphorylcholine head group but also with the hydrophobic core of liposomes.
Binding of PDC-109 to membranes is a very rapid, biphasic process with half times of less than one second. Maximal binding
of PDC-109 to small unilamellar vesicles was achieved with a stoichiometric ratio of 10–11 phosphatidylcholine molecules/PDC-109
molecule. Incorporation of phosphatidylethanolamine or phosphatidylserine into phosphatidylcholine vesicles reduced the binding
of PDC-109, suggesting that both the density of phosphorylcholine groups and the surface charge determine the interaction
of the seminal plasma protein with the surface of the membrane. Electron spin resonance measurements showed that binding of
PDC-109 to phosphatidylcholine vesicles caused a rigidification of the membrane. The relevance of the data for describing
the role of PDC-109 in the modulation of sperm capacitation is discussed.
Received: 16 June 1997 / Accepted: 10 September 1997 相似文献
947.
The Wolf-Hirschhorn syndrome (WHS) is caused by a partial deletion in the short arm of chromosome 4 band 16.3 (4p16.3). A unique-sequence human DNA probe (39 kb) localized within this region has been used to search for sequence homology in the apes' equivalent chromosome 3 by FISH-technique. The WHS loci are conserved in higher primates at the expected position. Nevertheless, a control probe, which detects alphoid sequences of the pericentromeric region of humans, is diverged in chimpanzee, gorilla, and orangutan. The conservation of WHS loci and divergence of DNA alphoid sequences have further added to the controversy concerning human descent. 相似文献
948.
949.
Partial purification and characterization of two cytoplasmic DNA polymerases from ungerminated wheat. 总被引:2,自引:1,他引:2 下载免费PDF全文
Two DNA polymerases have been purified from the 105,000 x g supernatant of ungerminated wheat. The purification stages included: high speed centrifugation, salt fractionation, DEAE-cellulose chromatography, Sephadex G-150 filtration and phosphocellulose chromatography. Several properties of the two enzyme (called A and B according to the order of elution from the phosphocellulose column) have been studied. Enzyme A has a sedimentation coefficient of about 7 S, utilizes activated DNA and synthetic polydeoxynucleotides as well as poly rA-dT12, while B has a sedimentation coefficient of about 6.2 and uses only activated DNA and synthetic polydeoxynucleotides as templates. Other parameters like KCl effect, MnCl2 effect, optimum pH, etc. Allow us to distinguish clearly between both DNA polymerases. 相似文献
950.
K. Böjthe-Horváth F. Hetényi Á. Kocsis L. Szabó M. Varga-Balázs I. Máthé P. Tétényi 《Phytochemistry》1980,21(12):2917-2919
From the aerial parts of Galium verum in flower, asperuloside and V1 iridoid were isolated. From the mother liquor obtained on recrystallizatio 相似文献