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991.
Arun Vishwanath Linda Brodsky Steve Shaha Michael Leonard Michael Cimino 《International journal of medical informatics》2009,78(5):330-339
Context
Medication error prevention is a priority for the U.S. healthcare system in the 21st century. Use of technology is considered by some as critical to achieve this goal. Knowledge of the attitudinal barriers to such adoption, however, is limited.Objective
To determine the attitudes of frontline prescriber clinicians towards technology in general, and PDAs specifically, before and after introduction of a PDA in the clinical setting of medication prescribing.Design
A pre- and post-intervention web-based survey, 12-14 months apart.Setting
Academic tertiary care children's hospital.Participants
Total of 244 prescriber clinicians.Intervention
Distribution of a PDA with pediatric-specific medication prescribing information after completion of an on-line medication safety certification and other safety focused educational sessions.Main outcome measures
Ratings (5-point Likert scale) reflecting perceptions and attitudes towards technology in general and technology in medical settings along with self-reported usage of the PDA for Rx.Results
Early Adopters and Late Adopters were identified statistically, and the group membership reflected their prior exposure to and ownership of other technologies. Early Adopters tended to be younger and less experienced clinically (e.g., residents) and more frequent owners and users of technology. Early Adopters expressed significantly more favorable attitudes toward technology and PDAs on both pre- to post-intervention survey occasions. They also utilized the PDA for Rx more often than LAs. Interestingly, PDA use for Early Adopters was based on its ease of use, while PDA use among later adopters was based on its clinical usefulness.Conclusions
Provision of point of care information using PDAs and a user-friendly, pediatric-specific medication information software package did not positively affect the attitudes of prescriber clinicians among those already favorable toward technology. However, a significant change was found among those with initially less favorable attitudes. Organizations need to understand the nature of both Early and Late Adopters and plan appropriately for managing the respective needs and expectations when potentially beneficial technologies are introduced. In order to ensure the success of an implementation, the training and supportive interventions need to be carefully designed and specifically catered to the personality-based outcome expectations of the prescriber. 相似文献992.
Linda K?hn Sara J Bowne Lori S Sullivan Stephen P Daiger Marie SI Burstedt Konstantin Kadzhaev Ola Sandgren Irina Golovleva 《European journal of human genetics : EJHG》2009,17(5):651-655
The aim of this study was to identify and characterize the underlying molecular mechanisms in autosomal-dominant retinitis pigmentosa (adRP) with incomplete penetrance in two Swedish families. An extended genealogical study and haplotype analysis indicated a common origin. Mutation identification was carried out by multiplex ligation-dependent probe amplification (MLPA) and sequencing. Clinical examinations of adRP families including electroretinography revealed obligate gene carriers without abnormalities, which indicated incomplete penetrance. Linkage analysis resulted in mapping of the disease locus to 19q13.42 (RP11). Sequence analyses did not reveal any mutations segregating with the disease in eight genes including PRPF31. Subsequent MLPA detected a large genomic deletion of 11 exons in the PRPF31 gene and, additionally, three genes upstream of the PRPF31. Breakpoints occurred in intron 11 of PRPF31 and in LOC441864, ‘similar to osteoclast-associated receptor isoform 5.'' An almost 59 kb deletion segregated with the disease in all affected individuals and was present in several asymptomatic family members but not in 20 simplex RP cases or 94 healthy controls tested by allele-specific PCR. A large genomic deletion resulting in almost entire loss of PRPF31 and three additional genes identified as the cause of adRP in two Swedish families provide an additional evidence that mechanism of the disease evolvement is haploinsufficiency. Identification of the deletion breakpoints allowed development of a simple tool for molecular testing of this genetic subtype of adRP. 相似文献
993.
Revenkova E Focarelli ML Susani L Paulis M Bassi MT Mannini L Frattini A Delia D Krantz I Vezzoni P Jessberger R Musio A 《Human molecular genetics》2009,18(3):418-427
Cornelia de Lange syndrome (CdLS) is a clinically heterogeneous developmental disorder characterized by facial dysmorphia, upper limb malformations, growth and cognitive retardation. Mutations in the sister chromatid cohesion factor genes NIPBL, SMC1A and SMC3 are present in approximately 65% of CdLS patients. In addition to their canonical roles in chromosome segregation, the cohesin proteins are involved in other biological processes such as regulation of gene expression, DNA repair and maintenance of genome stability. To gain insights into the molecular basis of CdLS, we analyzed the affinity of mutated SMC1A and SMC3 hinge domains for DNA. Mutated hinge dimers bind DNA with higher affinity than wild-type proteins. SMC1A- and SMC3-mutated CdLS cell lines display genomic instability and sensitivity to ionizing radiation and interstrand crosslinking agents. We propose that SMC1A and SMC3 CdLS mutations affect the dynamic association between SMC proteins and DNA, providing new clues to the underlying molecular cause of CdLS. 相似文献
994.
Michael J. Keherly Ching-Chyuan Hsieh Jerome L. McCombs Linda S. Merryman John Papaconstantinou 《Somatic Cell and Molecular Genetics》1996,22(2):119-134
We utilized an AFP-HPRT transgene, i.e. the HPRT coding sequences under the regulation of AFP enhancer and promoter sequences,
to localize the AFP extinguisher locus in intertypic somatic cell hybrids (hepatoma X fibroblast). This hybrid gene construct,
which directly links AFP regulation to a reversibly selective gene, enabled the selection of stably transfected cells which
express AFP, as well as cells showing extinction of AFP. Mouse hepatoma cells stably transfected with and expressing the transgene
were fused to human fibroblasts, and the resulting somatic cell hybrids were characterized using Southern, Northern and karyotypic
analyses. That several hybrids exhibited the proper extinction of AFP, AFP-HPRT and albumin suggests coregulation of these
genes by an extinguisher. Segregant lines derived from these hybrids were selected for the loss of extinguisher activity and
for reexpression of the transgene. Karyotypic analysis of hybrid and segregant lines, exhibiting proper AFP, albumin and AFP-HPRT
phenotypes, revealed that the presence of human chromosome 7 was most closely associated with the AFP-extinguished state.
The hybrids generated in these studies now make it possible to isolate the sequences responsible for AFP and albumin extinction. 相似文献
995.
996.
Krezowski J Knudson D Ebeling C Pitstick R Giri RK Schenk D Westaway D Younkin L Younkin SG Ashe KH Carlson GA 《Human molecular genetics》2004,13(18):1989-1997
Phenotypes produced by expression of human amyloid precursor protein (APP) transgenes vary depending on the genetic background of the mouse. FVB/N mice overexpressing human APP695 develop a central nervous system disorder and die prematurely, precluding development of Abeta peptide amyloid plaques. 129S6 mice are resistant to the lethal effects of APP overexpression, allowing sufficient levels of Abeta expression for the development of amyloid plaques and age-dependent memory deficits. To identify the genes that determine susceptibility or resistance to APP we analyzed crosses involving FVB/NCr and 129S6.Tg2576 mice that overexpress 'Swedish' mutant (K670N, M671L) APP695. APP transgene-positive FVB129S6F1 (F1) mice are resistant to the lethal effects of APP overexpression, so FVBxF1 backcross and F2 intercross offspring were produced. Analysis of age of death as a quantitative trait revealed significant linkage to loci on proximal chromosome 14 and on chromosome 9; 129S6 alleles protect against the lethal effects of APP. Within the chromosome 14 interval are segments homologous to regions on human chromosome 10 that have been linked to late onset Alzheimer's disease or to levels of Abeta peptide in plasma. However, analysis of plasma Abeta peptide concentrations at 6 weeks in backcross offspring produced no significant linkage. Similarly, elevation of human Abeta peptide concentrations by expression of mutant presenilin transgenes did not increase the proportion of mice dying prematurely, suggesting that early death reflects effects of APP or fragments other than Abeta. 相似文献
997.
998.
Ejim LJ D'Costa VM Elowe NH Loredo-Osti JC Malo D Wright GD 《Infection and immunity》2004,72(6):3310-3314
The biosynthesis of methionine in bacteria requires the mobilization of sulfur from Cys by the formation and degradation of cystathionine. Cystathionine beta-lyase, encoded by metC in bacteria and STR3 in Schizosaccharomyces pombe, catalyzes the breakdown of cystathionine to homocysteine, the penultimate step in methionine biosynthesis. This enzyme has been suggested to be the target for pyridinamine antimicrobial agents. We have demonstrated, by using purified enzymes from bacteria and yeast, that cystathionine beta-lyase is not the likely target of these agents. Nonetheless, an insertional inactivation of metC in Salmonella enterica serovar Typhimurium resulted in the attenuation of virulence in a mouse model of systemic infection. This result confirms a previous chemical validation of the Met biosynthetic pathway as a target for the development of antibacterial agents and demonstrates that cystathionine beta-lyase is important for bacterial virulence. 相似文献
999.
Ewing-Cobbs L Barnes M Fletcher JM Levin HS Swank PR Song J 《Developmental neuropsychology》2004,25(1-2):107-133
In a prospective longitudinal study, academic achievement scores were obtained from youth 5 to 15 years of age who sustained mild-moderate (n = 34) or severe (n = 43) traumatic brain injuries (TBI). Achievement scores were collected from baseline to 5 years following TBI and were subjected to individual growth curve analysis. The models fitted age at injury, years since injury, duration of impaired consciousness, and interaction effects to Reading Decoding, Reading Comprehension, Spelling, and Arithmetic standard scores. Although scores improved significantly over the follow-up relative to normative data from the standardization sample of the tests, children with severe TBI showed persistent deficits on all achievement scores in comparison to children with mild-moderate TBI. Interactions of the slope and age parameters for the Arithmetic and Reading Decoding scores indicated greater increases over time in achievement scores of the children injured at an older age, but deceleration in growth curves for the younger children with both mild-moderate and severe TBI. These results are compatible with the hypothesis that early brain injuries disrupt the acquisition of some academic skills. Hierarchical regression models revealed that indexes of academic achievement obtained 2 years following TBI had weak relations with the duration of impaired consciousness and socioeconomic status. In contrast, concurrent cognitive variables such as phonological processing and verbal memory accounted for more variability in academic scores. Given the significant and persistent decrement in basic academic skills in youth with severe TBI, it is clear that head-injured youth require intensive, long-term remediation and intervention not only of the academic skills themselves, but also of those cognitive abilities that support the development and maintenance of reading and math. 相似文献
1000.