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971.
Jiaming Zhang Daniel R. Hill Anne W. Sylvester 《植物学报(英文版)》2007,49(8):1129-1141
RAB guanosine triphosphatases (GTPases) are key regulators of vesicle trafficking and are essential to the growth and development of all eukaryotic cells. During evolution, the RAB family has expanded in different patterns to facilitate distinct cellular, developmental and physiological adaptations. Yeast has only 11 family members, whereas mammalian RABs have expanded to 18 RAB subfamilies. Plant RABs have diversified primarily by duplicating members within a single subfamily. Plant RABs are divided into eight subfamilies, corresponding to mammalian RAB1, RAB2, RAB5, RAB6, RAB7, RAB8, RAB11 and RAB18. Functional diversification of these is exemplified by the RAB1 ls, orthologs of which are partitioned into unique cell compartments in plants where they function to transport vesicles during localized tip growth. Similarly, the RAB2 family in grasses is likely involved in vesicle secretion associated with wall expansion, as determined by analysis of over-expression mutants. We propose that dicots and monocots have also diverged in their RAB profiles to accommodate unique cellular functions between the two groups. Here we present a bioinformatics analysis comparing the RAB sub-families of rice, maize and Arabidopsis. These results will guide future functional studies to test for the role of diversification of subfamilies unique to monocots compared to dicots. 相似文献
972.
973.
Susan Michie Stephen Pilling Philippa Garety Paula Whitty Martin P Eccles Marie Johnston Jemma Simmons 《Implementation science : IS》2007,2(1):1-8
Background
Monitoring and Messaging Devices (MMDs) are telehealth systems used by patients in their homes, and are designed to promote patient self-management, patient education, and clinical monitoring and follow-up activities. Although these systems have been widely promoted by health care systems, including the Veterans Health Administration, very little information is available on factors that facilitate use of the MMD system, or on barriers to use.Methods
We conducted in-depth qualitative interviews with clinicians using MMD-based telehealth programs at two Veterans Affairs Medical Centers in the Midwestern United States.Results
Findings suggest that MMD program enrollment is limited by both clinical and non-clinical factors, and that patients have varying levels of program participation and system use. Telehealth providers see MMDs as a useful tool for monitoring patients who are interested in working on management of their disease, but are concerned with technical challenges and the time commitment required to use MMDs.Conclusion
Telehealth includes a rapidly evolving and potentially promising range of technologies for meeting the growing number of patients and clinicians who face the challenges of diabetes care, and future research should explore the most effective means of ensuring successful program implementation. 相似文献974.
975.
Julien Boudet Anne Chouquet Aicha Chahboune Cécile Giustini Bernard Joris Jean-Pierre Simorre Catherine Bougault 《Biomolecular NMR assignments》2007,1(1):89-91
The ampG gene codes for a permease required to uptake anhydro-muropeptides into bacterial cytoplasm. Located upstream in the same
operon, is another 579-base-pair-long open reading frame encoding a putative lipoprotein YajG, whose nearly complete 1H,13C,15N assignments are reported here. 相似文献
976.
Goldman AS Guisinger VH Aikins M Amarillo ML Belizario VY Garshong B Gyapong J Kabali C Kamal HA Kanjilal S Kyelem D Lizardo J Malecela M Mubyazi G Nitièma PA Ramzy RM Streit TG Wallace A Brady MA Rheingans R Ottesen EA Haddix AC 《PLoS neglected tropical diseases》2007,1(1):e67
Background
Because lymphatic filariasis (LF) elimination efforts are hampered by a dearth of economic information about the cost of mass drug administration (MDA) programs (using either albendazole with diethylcarbamazine [DEC] or albendazole with ivermectin), a multicenter study was undertaken to determine the costs of MDA programs to interrupt transmission of infection with LF. Such results are particularly important because LF programs have the necessary diagnostic and treatment tools to eliminate the disease as a public health problem globally, and already by 2006, the Global Programme to Eliminate LF had initiated treatment programs covering over 400 million of the 1.3 billion people at risk.Methodology/Principal Findings
To obtain annual costs to carry out the MDA strategy, researchers from seven countries developed and followed a common cost analysis protocol designed to estimate 1) the total annual cost of the LF program, 2) the average cost per person treated, and 3) the relative contributions of the endemic countries and the external partners. Costs per person treated ranged from $0.06 to $2.23. Principal reasons for the variation were 1) the age (newness) of the MDA program, 2) the use of volunteers, and 3) the size of the population treated. Substantial contributions by governments were documented – generally 60%–90% of program operation costs, excluding costs of donated medications.Conclusions/Significance
MDA for LF elimination is comparatively inexpensive in relation to most other public health programs. Governments and communities make the predominant financial contributions to actual MDA implementation, not counting the cost of the drugs themselves. The results highlight the impact of the use of volunteers on program costs and provide specific cost data for 7 different countries that can be used as a basis both for modifying current programs and for developing new ones. 相似文献977.
The renewal and differentiation of Isl1+ cardiovascular progenitors are controlled by a Wnt/beta-catenin pathway 总被引:3,自引:0,他引:3
Qyang Y Martin-Puig S Chiravuri M Chen S Xu H Bu L Jiang X Lin L Granger A Moretti A Caron L Wu X Clarke J Taketo MM Laugwitz KL Moon RT Gruber P Evans SM Ding S Chien KR 《Cell Stem Cell》2007,1(2):165-179
Isl1(+) cardiovascular progenitors and their downstream progeny play a pivotal role in cardiogenesis and lineage diversification of the heart. The mechanisms that control their renewal and differentiation are largely unknown. Herein, we show that the Wnt/beta-catenin pathway is a major component by which cardiac mesenchymal cells modulate the prespecification, renewal, and differentiation of isl1(+) cardiovascular progenitors. This microenvironment can be reconstituted by a Wnt3a-secreting feeder layer with ES cell-derived, embryonic, and postnatal isl1(+) cardiovascular progenitors. In vivo activation of beta-catenin signaling in isl1(+) progenitors of the secondary heart field leads to their massive accumulation, inhibition of differentiation, and outflow tract (OFT) morphogenic defects. In addition, the mitosis rate in OFT myocytes is significantly reduced following beta-catenin deletion in isl1(+) precursors. Agents that manipulate Wnt signals can markedly expand isl1(+) progenitors from human neonatal hearts, a key advance toward the cloning of human isl1(+) heart progenitors. 相似文献
978.
Eshete M Marchbank MT Deutscher SL Sproat B Leszczynska G Malkiewicz A Agris PF 《The protein journal》2007,26(1):61-73
Protein recognition of RNA has been studied using Peptide Phage Display Libraries, but in the absence of RNA modifications.
Peptides from two libraries, selected for binding the modified anticodon stem and loop (ASL) of human tRNALys3 having 2-thiouridine (s2U34) and pseudouridine (Ψ39), bound the modified human ASLLys3(s2U34;Ψ39) preferentially and had significant homology with RNA binding proteins. Selected peptides were narrowed to a manageable number
using a less sensitive, but inexpensive assay before conducting intensive characterization. The affinity and specificity of
the best binding peptide (with an N-terminal fluorescein) were characterized by fluorescence spectrophotometry. The peptide
exhibited the highest binding affinity for ASLLys3(s2U34;Ψ39), followed by the hypermodified ASLLys3 (mcm5s2U34;ms2t6A37) and the unmodified ASLLys3, but bound poorly to singly modified ASLLys3 constructs (Ψ39, ms2t6A37,
s2U34), ASLLys1,2
(t6A37) and Escherichia coli ASLGlu (s2U34). Thus, RNA modifications are potentially important recognition elements for proteins and can be targets for selective recognition
by peptides. 相似文献
979.
Deletion of complement factor H-related genes CFHR1 and CFHR3 is associated with atypical hemolytic uremic syndrome
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Zipfel PF Edey M Heinen S Józsi M Richter H Misselwitz J Hoppe B Routledge D Strain L Hughes AE Goodship JA Licht C Goodship TH Skerka C 《PLoS genetics》2007,3(3):e41
Atypical hemolytic uremic syndrome (aHUS) is associated with defective complement regulation. Disease-associated mutations have been described in the genes encoding the complement regulators complement factor H, membrane cofactor protein, factor B, and factor I. In this study, we show in two independent cohorts of aHUS patients that deletion of two closely related genes, complement factor H-related 1 (CFHR1) and complement factor H-related 3 (CFHR3), increases the risk of aHUS. Amplification analysis and sequencing of genomic DNA of three affected individuals revealed a chromosomal deletion of approximately 84 kb in the RCA gene cluster, resulting in loss of the genes coding for CFHR1 and CFHR3, but leaving the genomic structure of factor H intact. The CFHR1 and CFHR3 genes are flanked by long homologous repeats with long interspersed nuclear elements (retrotransposons) and we suggest that nonallelic homologous recombination between these repeats results in the loss of the two genes. Impaired protection of erythrocytes from complement activation is observed in the serum of aHUS patients deficient in CFHR1 and CFHR3, thus suggesting a regulatory role for CFHR1 and CFHR3 in complement activation. The identification of CFHR1/CFHR3 deficiency in aHUS patients may lead to the design of new diagnostic approaches, such as enhanced testing for these genes. 相似文献
980.
Marko-Varga G Ogiwara A Nishimura T Kawamura T Fujii K Kawakami T Kyono Y Tu HK Anyoji H Kanazawa M Akimoto S Hirano T Tsuboi M Nishio K Hada S Jiang H Fukuoka M Nakata K Nishiwaki Y Kunito H Peers IS Harbron CG South MC Higenbottam T Nyberg F Kudoh S Kato H 《Journal of proteome research》2007,6(8):2925-2935
Personalized medicine allows the selection of treatments best suited to an individual patient and disease phenotype. To implement personalized medicine, effective tests predictive of response to treatment or susceptibility to adverse events are needed, and to develop a personalized medicine test, both high quality samples and reliable data are required. We review key features of state-of-the-art proteomic profiling and introduce further analytic developments to build a proteomic toolkit for use in personalized medicine approaches. The combination of novel analytical approaches in proteomic data generation, alignment and comparison permit translation of identified biomarkers into practical assays. We further propose an expanded statistical analysis to understand the sources of variability between individuals in terms of both protein expression and clinical variables and utilize this understanding in a predictive test. 相似文献