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61.
Molecular characterization of 3-phosphoglycerate dehydrogenase deficiency--a neurometabolic disorder associated with reduced L-serine biosynthesis 下载免费PDF全文
Klomp LW de Koning TJ Malingré HE van Beurden EA Brink M Opdam FL Duran M Jaeken J Pineda M Van Maldergem L Poll-The BT van den Berg IE Berger R 《American journal of human genetics》2000,67(6):1389-1399
3-phosphoglycerate dehydrogenase (PHGDH) deficiency is a disorder of L-serine biosynthesis that is characterized by congenital microcephaly, psychomotor retardation, and seizures. To investigate the molecular basis for this disorder, the PHGDH mRNA sequence was characterized, and six patients from four families were analyzed for sequence variations. Five patients from three different families were homozygous for a single nucleotide substitution predicted to change valine at position 490 to methionine. The sixth patient was homozygous for a valine to methionine substitution at position 425; both mutations are located in the carboxyterminal part of PHGDH. In vitro expression of these mutant proteins resulted in significant reduction of PHGDH enzyme activities. RNA-blot analysis indicated abundant expression of PHGDH in adult and fetal brain tissue. Taken together with the severe neurological impairment in our patients, the data presented in this paper suggest an important role for PHGDH activity and L-serine biosynthesis in the metabolism, development, and function of the central nervous system. 相似文献
62.
SUMMARY: MIPSIM is a computational package designed to analyse and compare 3D distributions of molecular interaction potentials (MIP) of series of biomolecules. 相似文献
63.
Kirschner RE Randall P Wang P Jawad AF Duran M Huang K Solot C Cohen M LaRossa D 《Plastic and reconstructive surgery》2000,105(6):2127-2132
We report the speech outcome in 90 children with complete unilateral cleft lip and palate who underwent soft palate repair either between 3 and 7 months of age (n = 40) or later than 7 months of age (n = 50). In all patients, palatoplasty was performed by one of two experienced surgeons using a modification of the Furlow technique, and speech evaluations were conducted using the Pittsburgh Weighted Values for Speech Symptoms Associated with Velopharyngeal Incompetence by two speech pathologists with high inter-rater reliability. There were no differences between the groups with respect to resonance, nasal air emission, and articulation. Velopharyngeal function, as measured by the total speech score, was similar between the two groups of patients, as were the rates of secondary pharyngoplasty. These results suggest that very early closure of the soft palate may not offer significant benefit over repair later in infancy with respect to speech outcome. 相似文献
64.
Miquel Lürling 《Journal of phycology》1998,34(4):578-586
Populations of the phenotypically plastic alga Scenedesmus acutus Meyen were cultured in standard medium or in medium with filtered water from a Daphnia culture to examine the expression of ecomorphs in both water types. A rapid formation of four- and eight-celled coenobia was observed in the presence of Daphnia water, but not in standard medium. Moreover, cell dimensions were increased in the Daphnia water containing medium. Population growth rates were comparable in both water types; however, the carrying capacity appeared significantly lower in Daphnia water. Daphnia needed to feed on digestible food to produce the colony-inducing chemicals; medium from starved animals and Daphnia fed polystyrene beads appeared inactive. Neither suspensions of homogenate of Scenedesmus and Cryptomonas nor auxins affected colony formation or growth rate in S. acutus. The colony-inducing infochemicals are probably not constituents of the algae themselves; however, modification of algal constituents in the digestive system of daphniids may be involved. 相似文献
65.
Thomas Landes Ingrid Leroy Ambre Bertholet Alan Diot Farnoosh Khosrobakhsh Marlène Daloyau Noélie Davezac Marie-Christine Miquel Delphine Courilleau Emmanuelle Guillou Aurélien Olichon Guy Lenaers Laetitia Arnauné-Pelloquin Laurent J. Emorine Pascale Belenguer 《Seminars in cell & developmental biology》2010,21(6):593-598
Mitochondrial morphology varies according to cell type and cellular context from an interconnected filamentous network to isolated dots. This morphological plasticity depends on mitochondrial dynamics, a balance between antagonistic forces of fission and fusion. DRP1 and FIS1 control mitochondrial outer membrane fission and Mitofusins its fusion. This review focuses on OPA1, one of the few known actors of inner membrane dynamics, whose mutations provoke an optic neuropathy. Since its first identification in 2000 the characterization of the functions of OPA1 has made rapid progress thus providing numerous clues to unravel the pathogenetic mechanisms of ADOA-1. 相似文献
66.
Blunted suppression of acyl‐ghrelin in response to fructose ingestion in obese adolescents: The role of insulin resistance 下载免费PDF全文
67.
A common variant in the MTNR1b gene is associated with increased risk of impaired fasting glucose (IFG) in youth with obesity 下载免费PDF全文
68.
Jean Yves Le Reste Patrice Nabbe Charles Rivet Charilaos Lygidakis Christa Doerr Slawomir Czachowski Heidrun Lingner Stella Argyriadou Djurdjica Lazic Radost Assenova Melida Hasaganic Miquel Angel Munoz Hans Thulesius Bernard Le Floch Jeremy Derriennic Agnieska Sowinska Harm Van Marwijk Claire Lietard Paul Van Royen 《PloS one》2015,10(1)
Background
Multimorbidity, according to the World Health Organization, exists when there are two or more chronic conditions in one patient. This definition seems inaccurate for the holistic approach to Family Medicine (FM) and long-term care. To avoid this pitfall the European General Practitioners Research Network (EGPRN) designed a comprehensive definition of multimorbidity using a systematic literature review.Objective
To translate that English definition into European languages and to validate the semantic, conceptual and cultural homogeneity of the translations for further research.Method
Forward translation of the EGPRN’s definition of multimorbidity followed by a Delphi consensus procedure assessment, a backward translation and a cultural check with all teams to ensure the homogeneity of the translations in their national context. Consensus was defined as 70% of the scores being higher than 6. Delphi rounds were repeated in each country until a consensus was reachedResults
229 European medical expert FPs participated in the study. Ten consensual translations of the EGPRN comprehensive definition of multimorbidity were achieved.Conclusion
A comprehensive definition of multimorbidity is now available in English and ten European languages for further collaborative research in FM and long-term care. 相似文献69.
T J Robinson H Cernohorska G Diedericks K Cabelova A Duran C A Matthee 《Heredity》2014,112(3):325-332
A South African endemic antelope, the Grey Rhebok (Pelea capreolus), has long been an evolutionary enigma in bovid systematics—its phylogenetic intractability attributed to its curious combination of derived and primitive morphological attributes and the consequences of a rapid radiation. By using a combination of DNA sequences, chromosomal characteristics and quantitative and qualitative morphological features we show that the species is a sister taxon to a clade that comprises the waterbuck, reedbuck and allies. Our finding of few unambiguous synapomorphies reinforces suggestions of a rapid radiation and highlights the effects of incomplete lineage sorting, including the hemiplasic nature of several chromosomal rearrangements. We investigate these data to address the general question of what may have led to Pelea being both genetically and ecologically distinct from the Reduncini. We argue that its adaptation to exposed habitats, free of standing water, arose by vicariance prompted by increasing aridity of the extreme south/southwestern region of the African continent in the Miocene. Ancestral lineages leading to the extant Redunca and Kobus, on the other hand, retreated to water-abundant refugia in the north during these mostly globally cool phases. The mosaic of water-rich environments provided by the Okavango and the drainage systems in the southwestern extension of the East African Rift system are considered to have facilitated speciation and chromosomal evolution within these antelope. 相似文献
70.
Albert Ruhí Eglantine Chappuis Daniel Escoriza Miquel Jover Jordi Sala Dani Boix Stéphanie Gascón Esperança Gacia 《Hydrobiologia》2014,723(1):25-39
Climate characteristics appear to play a key role in filtering organisms based on their biological traits. If this trait filtering by climate indeed occurs, it should have effects on the composition, dynamics, taxonomic relatedness and co-occurrence patterns of local assemblages, regardless of the taxonomic group considered. This preliminary study aimed to assess the extent to which environmental variables might determine these patterns in local communities and to evaluate whether the ultimate cross-taxon congruence relationships are consistent across, or dependent on, the selected region. To this end, we studied the bryophyte, macrophyte, macroinvertebrate, and amphibian communities in two clusters of temporary wetlands on the NE Iberian Peninsula under mesothermal and semiarid climates. We observed effects of environmental filtering, with the communities differing between the climatic regions not only in their compositions but also in their dynamics and taxonomic relatedness patterns. Although the cross-taxon congruence in terms of species richness was high in the mesothermal climate, most of the congruent relationships were disrupted in the semiarid environment. Overall, because climate-dependent patterns appear to prevail over climate-consistent ones, we suggest that the use of surrogate taxa may be of limited value when aiming to assess wetland biodiversity across large areas. 相似文献