Mutations in the retinal guanylate cyclase (RETGC-1) gene in dominant cone-rod dystrophy

The dominant cone-rod dystrophy gene CORD6 has previously been mapped to within an 8 cM interval on chromosome 17p12-p13. The retinal- specific guanylate cyclase gene (RETGC-1), which maps to within this genetic interval and previously was implicated in Leber's congenital amaurosis, was screened for mutations within this family and in a panel of small families and individuals with various cone and cone- rod dystrophy phenotypes. A missense mutation (E837D) was identified in affected members of the CORD6 family, as well as a second missense mutation (R838C) in three other families with dominant cone-rod dystrophy. RETGC-1 is only the fourth gene to be implicated in cone-rod dystrophy and this is the first report of dominant mutations in this gene.      

The spindle observation and its relationship with fertilization after intracytoplasmic sperm injection in living human oocytes

OBJECTIVE: To image spindles in living human oocytes and to examine the relation between spindles and fertilization after ICSI. DESIGN: The LC polscope was used to examine spindles in an observational study of living oocytes. SETTING: Academic IVF clinic. PATIENT(S): Women being treated for infertility. INTERVENTION(S): Oocytes retrieved from patients for infertility treatment were examined before ICSI. Aged, unfertilized oocytes after IVF or ICSI were examined with polscope and confocal microscopes to compare the two methods. MAIN OUTCOME MEASURE(S): Spindle structure in living oocytes and fertilization after ICSI. RESULT(S): Spindles could be imaged in 61.4% of oocytes. More oocytes with spindles than oocytes without spindles fertilized normally after ICSI (61.8% vs. 44.2%). Spindles in most aged oocytes were partially or completely disassembled, and only a few microtubules around the chromosomes or dispersed microtubules in the cytoplasm were observed. Confocal images of immunostained spindles were almost identical to polscope images of spindle birefringence. CONCLUSION(S): Spindles in living human oocytes can be imaged by using the polscope. A birefringent spindle in human oocytes may clinically predict the quality and age of oocytes. This method also can be used to monitor spindle position during ICSI.     

Circulatory shock

Patients with malignancy may present with acute circulatory compromise requiring ICU monitoring and care. The clinician must be familiar with a multiplicity of acute and chronic medical conditions common to the general population and also with conditions directly related to cancer or therapy thereof.     

Perceived benefits of word prediction intervention on written productivity in children with spina bifida and hydrocephalus

Word prediction has been commonly used as a tool to enhance written productivity. However, the effectiveness of word prediction as a strategy to meet this targeted outcome has not been established. Using a single-subject alternating treatments design, this study evaluated the effect of word prediction on written productivity from the users' perspectives. Three girls and one boy aged 10-12 with spina bifida and hydrocephalus participated in the study over a period of 20 days. The Canadian Occupational Performance Measure (COPM) was used to measure changes in perception of written productivity. Analysis of individual participant data showed that participants perceived word prediction to have the potential to influence written productivity on some writing tasks. Quantitative analysis using a randomization test did not reveal any significant changes in COPM scores after using word prediction. The varied abilities of the participants in the study and the small sample size may be the reasons why statistical analysis did not show any changes. The limitations of this study included use of a copy task, lack of a supporting measure to COPM and limited generalizability. Further studies with a larger sample are necessary to explore the skills required for successful use of word prediction and the impact of word prediction on specific tasks.     

Acute caffeine intake before and after fatiguing exercise improves target shooting engagement time

INTRODUCTION: Previous research has identified acute caffeine ingestion as an effective aid in counteracting the decline in vigilance experienced during sentry duty and sustained operations. However, further research is needed to clarify caffeine's effects under various stressors and additional operational conditions. The purpose of the present study was to examine the effect of caffeine on target detection and rifle marksmanship during simulated combat operations. METHODS: There were 12 reservists who ingested 5 mg x kg(-1) body mass of caffeine (C) or placebo (P) 1 h before beginning a 2.5-h loaded march and 1.0-h sandbag wall construction task. Following exercise, participants were given a re-dose of 2.5 mg x kg(-1) body mass of C or P. An hour after ingestion, participants commenced a 2.5-h shooting session on a small arms simulator, which included friend-foe discrimination (FF) and vigilance (VIG) tasks. Marksmanship performance measures included engagement time (ET), the number of shots fired (NS), accuracy, and precision. RESULTS: C ingestion (initial and/or redose) did not affect shooting performance during the FF task. ET and NS improved during the VIG task with C ingestion (mean +/- SD of 2.82 +/- 0.27 s and 29.2 +/- 1.9 shots out of 30 targets, respectively) compared with the P trial (3.00 +/- 0.26 s and 28.0 +/- 3.0 shots; p < 0.05). CONCLUSION: Caffeine ingestion improves target detection and engagement speed during vigilance situations, but is not effective during more complex operations requiring higher levels of cognitive processing and fine motor control and coordination.     

Novel therapies

OBJECTIVE: To highlight selected research directed to new drug and device technologies to manage mucositis in cancer patients and to illustrate potential impact of successful therapies. DATA SOURCES: Published research articles and abstracts, clinical experience. CONCLUSION: Advances in molecular modeling of mucosal injury in cancer patients have created new opportunities for therapy. Research is analyzing the impact of single-agent interventions; varying degrees of efficacy are being reported. Once optimal dosing strategies for single-agent management are defined, the opportunity for multi-agent therapies will emerge. IMPLICATIONS FOR NURSING PRACTICE: The oncology nurse plays a pivotal role in assessing and managing mucositis in cancer patients.