The effects of remote ischaemic preconditioning on coronary artery function in patients with stable coronary artery disease.

BACKGROUND: Remote ischaemic preconditioning (RIPC) is a cardioprotective intervention invoking intermittent periods of ischaemia in a tissue or organ remote from the heart. The mechanisms of this effect are incompletely understood. We hypothesised that RIPC might enhance coronary vasodilatation by an endothelium-dependent mechanism. METHODS: We performed a prospective, randomised, sham-controlled, blinded clinical trial. Patients with stable coronary artery disease (CAD) undergoing elective invasive management were prospectively enrolled, and randomised to RIPC or sham (1:1) prior to angiography. Endothelial-dependent vasodilator function was assessed in a non-target coronary artery with intracoronary infusion of incremental acetylcholine doses (10-6, 10-5, 10-4mol/l). Venous blood was sampled pre- and post-RIPC or sham, and analysed for circulating markers of endothelial function. Coronary luminal diameter was assessed by quantitative coronary angiography. The primary outcome was the between-group difference in the mean percentage change in coronary luminal diameter following the maximal acetylcholine dose (Clinicaltrials.gov identifier: NCT02666235). RESULTS: 75 patients were enrolled. Following angiography, 60 patients (mean±SD age 57.5±8.5years; 80% male) were eligible and completed the protocol (n=30 RIPC, n=30 sham). The mean percentage change in coronary luminal diameter was -13.3±22.3% and -2.0±17.2% in the sham and RIPC groups respectively (difference 11.32%, 95%CI: 1.2- 21.4, p=0.032). This remained significant when age and sex were included as covariates (difference 11.01%, 95%CI: 1.01- 21.0, p=0.035). There were no between-group differences in endothelial-independent vasodilation, ECG parameters or circulating markers of endothelial function. CONCLUSIONS: RIPC attenuates the extent of vasoconstriction induced by intracoronary acetylcholine infusion. This endothelium-dependent mechanism may contribute to the cardioprotective effects of RIPC.

Evidence for genetic heterogeneity within eight glaucoma families, with the GLC1A Gln368STOP mutation being an important phenotypic modifier.

OBJECTIVE: To investigate the phenotype and age-related penetrance of primary open-angle glaucoma (POAG) in Australian families with the most common Myocilin mutation (Gln368STOP). DESIGN: Cross-sectional genetic study. PARTICIPANTS: Eight pedigrees carrying the Gln368STOP mutation were ascertained from 1730 consecutive cases of POAG in the Glaucoma Inheritance Study in Tasmania. METHODS: Index cases and available family members were examined for signs of glaucoma, and the presence of the GLC1A Gln368STOP mutation was ascertained by single-strand conformation polymorphism analysis and subsequent direct sequencing. RESULTS: From the eight pedigrees, 29 Gln368STOP mutation-carrying individuals with either ocular hypertension (OHT) or POAG were found, with a mean age at diagnosis of 52.4 +/- 12.9 years and a mean peak intraocular pressure (IOP) of 28.4 +/- 4.7 mmHg. A further 11 mutation carriers older than 40 years have been studied, who as yet show no signs of OHT or POAG. Within the 8 pedigrees, a further 31 individuals with OHT or POAG were identified who did not carry the Gln368STOP mutation. For these individuals the mean age at diagnosis was higher (62.3 +/- 13.7 years, P < 0.01), and the mean peak IOP was lower (25.4 +/- 6.4 mmHg, P = 0.01). For Gln368STOP carriers, age-related penetrance for OHT or POAG was 72% at age 40 years and 82% at age 65 years. A positive family history of POAG was present in all index cases. Five of the eight pedigrees had a positive family history on both maternal and paternal sides. Seven of the eight pedigrees had one or more individuals with POAG who did not carry the mutation. Eight of the 29 Gln368STOP carriers with OHT or POAG had undergone trabeculectomy. CONCLUSIONS: The GLC1A Gln368STOP mutation is associated with POAG, which in the pedigrees studied is of a younger age of onset and higher peak IOP than non-mutation glaucoma cases. In addition, Gln368STOP mutation glaucoma cases were more likely to have undergone glaucoma drainage surgery. We have not observed simple autosomal dominant inheritance patterns for POAG in these pedigrees. Other factors, as yet uncharacterized, are involved in expression of the POAG phenotype in Gln368STOP pedigrees.

Information technology in maternal/child nursing: past, present, and future.

This issue commemorates the remarkable 25-year span of MCN, a journal born at the dawn of the microcomputer revolution. Key events in computer history and nursing informatics are chronicled, followed with visions of future technologies. A review of the technology literature published in MCN is summarized. Clinical implications include four nursing strategies for integrating electronic technology into practice and a list of online information resources.

Computer analysis of the fetal heart rate.

Computer analysis of the fetal heart rate is a technology of the Information Age commercially available for research and clinical practice. Intelligent systems are engineered with algorithms or neural networks designed to simulate expert knowledge. Automated analysis has provided objective, standardized, and reproducible data used to research fetal heart rate responses in the antepartum and intrapartum setting. Perinatal information systems can integrate FHR analysis and data management.

Accuracy and implications of a reported family history of glaucoma: experience from the Glaucoma Inheritance Study in Tasmania.

OBJECTIVES: To ascertain the prevalence of previously undiagnosed primary open-angle glaucoma (POAG) within 5 large POAG pedigrees and to evaluate the reliability of a reported family history of glaucoma within these pedigrees. METHODS: The Glaucoma Inheritance Study in Tasmania (GIST) identified several large adult POAG pedigrees. Intraocular pressure (IOP), optic disc stereophotography, and automated perimetry were performed on all adult pedigree members. Participants were classified as normal (IOP <22 mm Hg and normal optic disc and field); glaucoma suspect (normal field, but an IOP >/=22 mm Hg and/or suspicious optic disc); or POAG (field defect and glaucomatous optic disc). Some individuals with POAG had been previously diagnosed by their local ophthalmologist; others were diagnosed as a result of the GIST project. Family members with a prior diagnosis of POAG were asked to report if they were aware of any relatives with POAG. This reported family history was then directly compared with the actual pedigree (before the diagnosis of new cases) to calculate agreement. MAIN OUTCOME MEASURE: The rate of glaucoma in pedigrees and percentage of previously diagnosed glaucoma cases who were aware of the positive family history of POAG. RESULTS: Four hundred forty-two subjects (mean age, 54 years [range, 13-97 years]) from 5 pedigrees were examined: 316 subjects (71%) were normal, 47 (11%) were previously diagnosed with POAG, and 8 (2%) were previously diagnosed glaucoma suspects; 30 cases (7%) of POAG and 41 suspects (9%) were newly diagnosed as a direct result of the GIST examination. Of the 47 previously diagnosed POAG cases, 41 were questioned about their prior knowledge of any family history and 11 (27%) were unaware of their family history of POAG. CONCLUSIONS: Examination of all adult subjects from POAG families yields new cases. Even in large POAG pedigrees, 27% of previously diagnosed POAG patients were unaware of their positive family history. These findings suggest that a higher percentage of adult POAG may be inherited than hitherto reported. Arch Ophthalmol. 2000;118:900-904

History and development of fetal heart assessment: a composite.

Methods of assessing the fetal heart remained unchanged for approximately 150 years until the first commercial monitor suitable for clinical practice was sold in 1968. The impact and events of the last 30 to 40 years surrounding fetal heart assessment are revealed in perspectives of the past, present, and near future. Assessment practices have been shaped by the development of biotechnology, unrealistic expectations, interpretation disagreement, consumer response, and the practice and educational resources written by nursing and medicine.

Internet communication and discussion lists for perinatal nurses.

The article describes how electronic connectivity facilitates professional communication. A brief background in computer communication networks, telecommunications and Internet access, email, and electronic discussion lists prepares the reader to participate in this technology. Directions for subscribing to an online discussion list and guidelines for professional behavior on the Internet are outlined. The article concludes with a description of the Perinatal Nursing Discussion List, an established networking tool. Printed and electronic resources for locating additional lists and a glossary of online abbreviations and terms are included.

Clinical features associated with mutations in the chromosome 1 open-angle glaucoma gene (GLC1A)

BACKGROUND: A substantial proportion of cases of glaucoma have a genetic basis. Mutations causing glaucoma have been identified in the chromosome 1 open-angle glaucoma gene (GLC1A), which encodes a 57-kd protein known as myocilin. The normal role of this protein and the mechanism by which mutations cause glaucoma are not known. METHODS: We screened 716 patients with primary open-angle glaucoma and 596 control subjects for sequence changes in the GLC1A gene. RESULTS: We identified 16 sequence variations that met the criteria for a probable disease-causing mutation because they altered the predicted amino acid sequence and they were found in one or more patients with glaucoma, in less than 1 percent of the control subjects. These 16 mutations were found in 33 patients (4.6 percent). Six of the mutations were found in more than 1 subject (total, 99). Clinical features associated with these six mutations included an age at diagnosis ranging from 8 to 77 years and maximal recorded intraocular pressures ranging from 12 to 77 mm Hg. CONCLUSIONS: A variety of mutations in the GLC1A gene are associated with glaucoma. The spectrum of disease can range from juvenile glaucoma to typical late-onset primary open-angle glaucoma.