MLL2 mutation detection in 86 patients with Kabuki syndrome: a genotype-phenotype study.

Recently, pathogenic variants in the MLL2 gene were identified as the most common cause of Kabuki (Niikawa-Kuroki) syndrome (MIM#147920). To further elucidate the genotype-phenotype correlation, we studied a large cohort of 86 clinically defined patients with Kabuki syndrome (KS) for mutations in MLL2. All patients were assessed using a standardized phenotype list and all were scored using a newly developed clinical score list for KS (MLL2-Kabuki score 0-10). Sequencing of the full coding region and intron-exon boundaries of MLL2 identified a total of 45 likely pathogenic mutations (52%): 31 nonsense, 10 missense and four splice-site mutations, 34 of which were novel. In five additional patients, novel, i.e. non-dbSNP132 variants of clinically unknown relevance, were identified. Patients with likely pathogenic nonsense or missense MLL2 mutations were usually more severely affected (median 'MLL2-Kabuki score' of 6) as compared to the patients without MLL2 mutations (median 'MLL2-Kabuki score' of 5), a significant difference (p < 0.0014). Several typical facial features such as large dysplastic ears, arched eyebrows with sparse lateral third, blue sclerae, a flat nasal tip with a broad nasal root, and a thin upper and a full lower lip were observed more often in mutation positive patients.

The apoptosis-promoting factor TIA-1 is a regulator of alternative pre-mRNA splicing.

We report here that the apoptosis-promoting protein TIA-1 regulates alternative pre-mRNA splicing of the Drosophila melanogaster gene male-specific-lethal 2 and of the human apoptotic gene Fas. TIA-1 associates selectively with pre-mRNAs that contain 5' splice sites followed by U-rich sequences. TIA-1 binding to the U-rich stretches facilitates 5' splice site recognition by U1 snRNP. This activity is critical for activation of the weak 5' splice site of msl-2 and for modulating the choice of splice site partner in Fas. Structural and functional similarities with the Saccharomyces cerevisiae splicing factor Nam8 suggest striking evolutionary conservation of a mechanism of pre-mRNA splicing regulation that controls biological processes as diverse as meiosis in yeast, dosage compensation in fruit flies, or programmed cell death in humans.

Interaction of the U3-55k protein with U3 snoRNA is mediated by the box B/C motif of U3 and the WD repeats of U3-55k.

U3 small nucleolar RNA (snoRNA) is a member of the Box C/D family of snoRNAs which functions in ribosomal RNA processing. U3-55k is a protein that has been found to interact with U3 but not other members of the Box C/D snoRNA family. We have found that interaction of the U3-55k protein with U3 RNA in vivo is mediated by the conserved Box B/C motif which is unique to U3 snoRNA. Mutation of Box B and Box C, but not of other conserved sequence elements, disrupted interaction of U3-55k with U3 RNA. Furthermore, a fragment of U3 containing only these two conserved elements was bound by U3-55k in vivo. RNA binding assays performed in vitro indicate that Box C may be the primary determinant of the interaction. We have cloned the cDNA encoding the Xenopus laevis U3-55k protein and find strong homology to the human sequence, including six WD repeats. Deletion of WD repeats or sequences near the C-terminus of U3-55k resulted in loss of association with U3 RNA and also loss of localization of U3-55k to the nucleolus, suggesting that protein-protein interactions contribute to the localization and RNA binding of U3-55k in vivo.

The roles of Rrp5p in the synthesis of yeast 18S and 5.8S rRNA can be functionally and physically separated.

The yeast nucleolar protein Rrp5p is the only known trans-acting factor that is essential for the synthesis of both 18S rRNA and the major, short form of 5.8S (5.8Ss) rRNA, which were thought to be produced in two independent sets of pre-rRNA processing reactions. To identify domains within Rrp5p required for either processing pathway, we have analyzed a set of eight deletion mutants that together cover the entire RRP5 sequence. Surprisingly, only one of the deletions is lethal, indicating that regions encompassing about 80% of the protein can be removed individually without disrupting its essential biological function. Biochemical analysis clearly demonstrated the presence of two distinct functional domains. Removal of each of three contiguous segments from the N-terminal half specifically inhibits the formation of 5.8Ss rRNA, whereas deleting part of the C-terminal region of the protein only blocks the production of 18S rRNA. The latter phenotype is also caused by a temperature-sensitive mutation within the same C-terminal region. The two functional regions identified by the mutational analysis appear to be correlated with the structural domains detected by computer analysis. They can even be physically separated, as demonstrated by the fact that full Rrp5p activity can be supplied by two contiguous protein fragments expressed in trans.

Improving patient follow-up through implementation of an ambulatory care quality improvement program.

Nurse practitioners in ambulatory care settings must begin using quality improvement strategies to enhance patient outcomes and to improve patient follow-up. The article highlights the development and beginning stages of implementation of one such quality improvement program and discusses the actions that were taken to increase timeliness of key patient processes. An example of a quality improvement educational program, outlines of the plan, and scope of services are also provided.

An evaluation of the effectiveness of competency-based code blue education.

Two types of mock code programs were compared. The specific factors investigated were nurse satisfaction, comfort, and retention of knowledge and skills. A sample of 48 nurses initially participated in the mock code program, with 45 nurses participating in the 6-month follow-up evaluation. The study revealed that competency-based and group code blue programs resulted in similar levels of satisfaction, knowledge, and rate of performance of critical elements 6 months after the initial program.

Examining competency-based orientation implementation.

A competency-based orientation program provides a structured, comprehensive approach to the process of orientation. However, the program is only as good as the implementation. It is important for management, preceptors, and orientees to be knowledgeable of the details of the program and the procedures involved in the implementation process. when problems arise, it is important that all those involved solve the problems in an organized, systematic fashion.

Nurse-managed cancer-screening clinic.

As many institutions are reconfiguring the work environment to compete within the managed care arena, nurse-managed clinics can be one cost-effective option in which advanced practice nurses can further enhance the quality and efficiency of health care services provided by the primary care physicians in this everchanging health care arena.

Improving technology: blood glucose testing.

Nurses frequently monitor blood glucose at the patient's bedside, allowing timely assessment and interventions. To meet the Joint Commission on Accreditation of Health Organization's requirements and guidelines from National Committee on Clinical Laboratory Standards and College of American Pathologists, quality control compliance must be maintained. After testing three blood glucose monitors, one institution selected a machine that eliminated handwritten documentation, ensured quality control testing, and improved ease of use.