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91.
Septins: a ring to part mother and daughter 总被引:15,自引:0,他引:15
The septins are well conserved GTPases found in animals and fungi. In yeast, they are required for the formation of 10-nm filaments, with which they co-localize at the bud neck. Therefore, septins have been proposed to be components of the neck filaments and to have polymerization properties. In support of this hypothesis, septin complexes purified from yeast and flies form filaments in vitro. However, recent studies have questioned the relevance of septin filament formation for septin function. Particularly, septin polymerization may not be required for their function in cytokinesis. New septin functions have also been recently uncovered: in budding yeast, the septin ring is required for the maintenance of cell polarity. It forms a cortical barrier that prevents lateral diffusion of membrane-associated proteins through the bud neck. Here, we review the most recent functional and biochemical data, to discuss whether there is a link between septin polymerization properties and septin function. 相似文献
92.
Genetic polymorphism of cytomegalovirus strains responsible of congenital infections 总被引:1,自引:0,他引:1
Picone O Costa JM Ville Y Chaix ML Rouzioux C Leruez-Ville M 《Pathologie-biologie》2004,52(9):534-539
OBJECTIVES: Congenital Cytomegalovirus (CMV) infection is the main cause of neurological handicap in young children. The objective for studying genetic polymorphism of strains responsible for congenital infection is to identify CMV strains or groups of strains which would be more frequent in this context and/or which would be responsible for more severe congenital infection. METHODS: In this paper, we report and analyze the literature concerning the genetic polymorphism of CMV strains responsible of congenital infection, in the genes coding for the envelop protein B and the non structural UL144 protein and in the CMV short tandem repeats. RESULTS AND CONCLUSION: All UL144 and gB genotypes can be vertically transmitted from mothers to fetuses, none of these studies has shown any link between the genotypes and the severity of congenital disease. Moreover, no link between short tandem repeats polymorphism and severity of congenital disease has been demonstrated. However, short tandem repeats analysis may be a powerful tool to study the epidemiology of CMV congenital infections. 相似文献
93.
Alain Verloes Yves Gillerot Jean-Paul Langhendries Jean-Pierre Fryns Lucien Koulischer 《American journal of medical genetics. Part A》1992,43(4):669-677
We report on a case of neonatal hypothalamic hamartoblastoma with holoprosencephaly, Hirschsprung disease, and tetramelic postaxial polydactyly. Twenty-seven previous cases of congenital hypothalamic embryonic tumours with associated congenital defects are reviewed. A classification in isolated, associated, and syndromal forms is proposed. The difficulties encountered in differential diagnosis between the syndromal form (mainly represented by the Pallister-Hall syndrome) and related diseases as Smith-Lemli-Opitz type II, holoprosencephaly-polydactyly, orofaciodigital type VI and hydrolethalus syndromes are outlined. Two pathogenic mechanisms are discussed: a classical pleiotropic model and single sequence model. The latter is sufficient to delineate syndromal hypothalamic hamartoblastoma. With the former, syndromal hypothalamic hamartoblastoma cannot be clearly recognized in the absence of a CNS tumour, a child with syndromal hypothalamic hamartoblastoma cannot be reliably diagnosed as Pallister-Hall rather than another MCA syndrome, and, ultimately, the existence of Pallister-Hall syndrome could be questioned, as it could only be the extreme expression of one or several other syndromes. As this hypothesis cannot be proven or disproven at this point, the authors suggest creating the concept of multiplex phenotype. “Cerebro-Acro-Visceral Early lethality multiplex syndrome” is suggested to encompass all the ambiguous cases. Within this complex, an operative classification key is proposed. © 1992 Wiley-Liss, Inc. 相似文献
94.
Vincent Guion Philipe De Souto Barreto Yves Rolland 《Journal of the American Medical Directors Association》2021,22(2):393-398.e3
ObjectiveTo describe nursing home residents’ (NHRs) functional trajectories and mortality after a transfer to the emergency department (ED).DesignCase-control observational multicenter study.Setting and ParticipantsIn total, 1037 NHRs presenting to 17 EDs in France over 4 nonconsecutive weeks in 2016.MethodsFinite mixture models were fitted to longitudinal data on activities of daily living (ADL) scores before transfer (time 1), during hospitalization (time 2), and within 1 week after discharge (time 3) to identify groups of NHRs following similar functional evolution. Factors associated with mortality were investigated by Cox regressions.ResultsTrajectory modeling identified 4 distinct trajectories of ADL. The first showed a high and stable (across time 1, time 2, and time 3) functional capacity around 5.2/6 ADL points, with breathlessness as the main condition leading to transfer. The second displayed an initial 37.8% decrease in baseline ADL performance (between time 1 and time 2), followed by a 12.5% recovery of baseline ADL performance (time 2?time 3), with fractures as the main condition. The third displayed a similar initial decrease, followed by a 6.7% recovery. The fourth displayed an initial 70.1% decrease, followed by an 8.5% recover, with more complex geriatric polypathology situations. Functional decline was more likely after being transferred for a cerebrovascular condition or for a fracture, after being discharged from ED to a surgery department, and with a heavier burden of distressing symptoms during transfer. Mortality after ED transfer was more likely in older NHRs, those in a more severe condition, those who were hospitalized more frequently in the past month, and those transferred for cerebrovascular conditions or breathlessness.Conclusions and ImplicationsIdentified trajectories and factors associated with functional decline and mortality should help clinicians decide whether to transfer NHRs to ED. NHRs with high functional ability seem to benefit from ED transfers whereas on-site alternatives should be sought for those with poor functional ability. 相似文献
95.
Ben Khadhra Hajer Rose-Robert Françoise Herpe Yves Edouard Sevestre Henri Choukroun Gabriel Catherine Luc Amant Carole Saint Fabien 《International urology and nephrology》2021,53(1):59-67
International Urology and Nephrology - Biomarkers for the diagnosis and monitoring treatment response of kidney cancer are urgently needed. Neutrophil gelatinase-associated lipocalin (NGAL) is a... 相似文献
96.
97.
Yann Gouëffic Jean L. Pin Jean Sabatier Yves Alimi Eric Steinmetz Pierre-Edouard Magnan Olivier Marret Adrien Kaladji Bertrand Chavent Benjamin Kretz Alexandra Jobert Solène Schirr-Bonnans Béatrice Guyomarc'h Valéry P. Riche Lucie S. du Mont Philippe Tessier 《European journal of vascular and endovascular surgery》2021,61(3):447-455
98.
Ouhibi Nadia; Menezo Yves; Benet Gerard; Nicollet Bernard 《Human reproduction (Oxford, England)》1989,4(3):229-235
This study proposes a procedure for the isolation and cultureof oviduct epithelial cells of several species. In-vitro cultureon such a feeder seems to allow full embryonic development andviability. The inner linings of Fallopian tubes from mouse,rabbit, cow and human were trypsinized and the epithelial cellswere enriched with Percoll gradient. Isolated cells, obtainedin high yield with good viability, were maintained in monolayerculture in B2-Menezo medium supplemented with serum, which alsosupports early embryonic development in vitro. The plated primarycultures reached confluence within 8 days, producting a monolayerof cohesive polygonalcells. Associated with this large epithelialcall population, ciliated cells as wellas polykaryotic cellsand few fibroblastic nestswere observed. After the first sub-culture,the ciliated cells disappeared and the epithelial cell monolayergrew rapidly to confluence with in 3 days and displayed contactinhibition. No epithelial cell growth could be obtained inculturein the absence of serum. The addition of oestrogens had no effecton any of the cultured oviductal epithelial cells. A sponotaneousalteration was observed in morphology and growth after severalpassages, the number of which depends mainly upon the species 相似文献
99.
Armin Junghardt Hannes Wildberger Yves Robert Bela Török 《Documenta ophthalmologica. Advances in ophthalmology》1993,83(2):139-149
The pattern electroretinogram and the visual evoked potential were recorded simultaneously with various stimulus fields and artificial scotomata of increasing sizes. In contrast to an earlier study, a smaller check size (20) and two stimulus field sizes (20° × 20° and 10° × 10°) for the scotomata were used. With a concentric decreasing stimulus field, a reduction of both the pattern electroretinogram and visual evoked potential was found. Both showed a simultaneous reduction of amplitudes, but, compared with the amplitude in the full field, the reduction was more extensive for the pattern electroretinogram at each test field size. This implies a greater contribution to the pattern electroretinogram from more eccentric retinal parts. An artificial central scotoma of increasing size in the 20° × 20° field had less influence on the pattern electroretinogram than on the visual evoked potential. The percentage amplitude loss of the visual evoked potential was more pronounced. The visual evoked potential was eventually abolished by a scotoma size from 10° × 10° upward, while the pattern electroretinogram was still registrable. When scotomata of similar size were introduced in a smaller (10° × 10°) field, percentage pattern electroretinogram and visual evoked potential amplitude losses were less separated than in a larger (20° × 20°) test field. 相似文献
100.