Contributors to cognitive impairment in congestive heart failure: a pilot case-control study.

BACKGROUND: Cognitive impairment and heart failure are both serious health problems related to population ageing. Impaired cognitive function is an important but underrecognized complication of congestive heart failure (CHF). The aim of the study was to examine the sociodemographic, clinical, neuroimaging and biochemical parameters affecting cognition in CHF. METHODS: Thirty-one patients with CHF (left-ventricular ejection fraction < 40%) and 24 controls without CHF, all free of clinically significant cognitive impairment, participating in a case-control study were assessed using a cognitive battery (CAMCOG), a depression scale, 6-min-walk test, left-ventricular ejection fraction, semi-quantitative magnetic resonance imaging, and cortisol, aldosterone and renin concentrations. RESULTS: The CHF patients had lower CAMCOG scores than controls (93.5 +/- 6.1 vs 99.9 +/- 2.4, P < 0.001) and had significantly lower scores on visuospatial, executive function, visual memory and verbal learning tasks. Concentrations of renin and aldosterone were higher in patients with CHF (5.4 +/- 6.0 vs 0.8 +/- 0.7 mU/L, P < 0.001 and 598.2 +/- 306.2 vs 346.0 +/- 201.5, P= 0.003). Right medial temporal lobe atrophy was more prominent in CHF (P= 0.030). Left medial temporal lobe atrophy and deep white matter hyperintensities showed moderate association with cognitive scores in CHF, whereas functional capacity and biochemical parameters were fairly correlated to cognition. CONCLUSION: Congestive heart failure is associated with a pattern of generalized cognitive decline. Structural brain changes, functional capacity and biochemical parameters are associated with the cognitive performance of patients with CHF, but their contribution appears modest. The design of a definitive case-control study is described.

HbA1c Is Associated with Frailty in a Group of Aboriginal Australians.

In this cross-sectional study of 141 Aboriginal Australians aged ≥45 years living in the remote Kimberley region of Western Australia, we explored whether glycated haemoglobin (HbA1c) levels were associated with frailty. Sixty-four participants (45.4%) had a HbA1c level ≥6.5% and 84 participants (59.6%) were frail. A significant trend was observed with regard to HbA1c levels and frailty, with those having HbA1c levels ≥6.5% having the greatest prevalence of frailty (70.3%). In binary logistic regression analyses, having a HbA1c level ≥6.5% was associated with being frail after adjustment for age, sex, and education. This association was attenuated after further adjustment for body mass index (BMI). Poorer glycaemic control is very common and a potential risk factor for frailty in remote-living Aboriginal Australians, and appears to be partly mediated by BMI, a known risk factor for diabetes mellitus. Obesity and diabetes mellitus are potentially important modifiable risk factors for frailty.

The use of the laryngeal mask in surgical tracheostomy.

The laryngeal mask may be used as an airway during surgical tracheostomy. This techniques has several advantages over conventional oral endotracheal intubation.

Developing and implementing a wound care program in long-term care.

Pressure ulcers in residents of long-term care facilities cause avoidable pain and suffering, and they place an additional burden on budgets that are already quite lean. To laypersons, these "bedsores" inaccurately enhance a widely held belief that nursing homes provide inferior care. Although most long-term care administrators recognize the need for better prevention and management of pressure ulcers, they lack specialized knowledge in the field of wound prevention and treatment and lack the necessary time to devote to such an effort. A systematic approach using prevention and treatment protocols and a wound care team and staff education, has proved highly effective in reducing the incidence of pressure ulcerations. This article provides a detailed guide for the development and implementation of a wound prevention and care program and defines the critical role played by the WOC nurse within such a program.

Antimicrobial efficacy of AvGard carcase wash under industrial processing conditions.

1. The efficacy of the AvGard Trisodium Phosphate (TSP) immersion carcase wash process was evaluated during 5 industrial trials against Salmonella, Enterobacteriaceae, thermotolerant coliforms and total aerobic count. The effect against Pseudomonas was also studied in the first 3 trials. 2. Dramatic reductions in Salmonella incidence were seen using a whole carcase rinse method. In 4 of the 5 trial sites, only one positive sample was found after AvGard treatment (average 0.5% incidence), in spite of an average control incidence of 57.7%. In the 5th site, a water-chilled broiler plant, an average control incidence of 74.0% was reduced to 9.4% after AvGard treatment. 3. In the latter case, Most Probable Number (MPN) analyses were performed on some of the Salmonella positive samples taken from the control and post-treatment series; the average MPN count per carcase on controls was 115, whereas for AvGard treated birds the figure was only 0.6 per carcase, a greater than 2 log reduction. 4. In addition, AvGard treatment gave average log reductions for all trials of: Enterobacteriaceae; 2.5 log; Coliforms; 2.7 log, and Total Aerobic Count; 1.1 log, leading to carcases substantially free of Gram negative pathogens. 5. Pseudomonas was reduced by an average of 1.7 log in the first 3 trials, dramatically reducing the carcase loading of this important spoilage organism.

Anaesthesia and congenital agranulocytosis: influence of anaesthetic agent on neutrophil numbers in a patient with Kostmann's syndrome.

We describe a 14-month-old male patient with congenital agranulocytosis who received general anaesthesia on three separate occasions during a 6-week period for minor surgery. Granulocyte colony stimulating factor was commenced after the second anaesthetic. Each anaesthetic was followed by profound reductions in neutrophil numbers, irrespective of the agent used. Even the third anaesthetic, which avoided all the common agents thought to have a marrow suppressant effect and given during granulocyte colony stimulating factor therapy, was associated with a marked decrease in neutrophil numbers.

Repair of traumatic transection of the thoracic aorta: esmolol for intraoperative control of arterial pressure.

We report the intraoperative use of esmolol for control of arterial pressure during repair of a traumatic transection of the descending thoracic aorta. A mean infusion rate of esmolol 50.5 micrograms kg-1 min-1 resulted in a decrease in mean arterial pressure to 63 mm Hg and heart rate to 99 beat min-1 and was associated with excellent surgical conditions. The infusion rate of esmolol was titrated easily against mean arterial pressure, which increased rapidly on discontinuing its infusion. Control of arterial pressure with esmolol was comparable to that achieved with sodium nitroprusside, but without the reflex tachycardia or decrease in Pao2 associated with the latter agent.

Teaching fibreoptic nasotracheal intubation with and without closed circuit television.

We have compared the progress of anaesthetists taught fibreoptic nasotracheal intubation with the aid of a closed circuit television (CCTV) system with that of anaesthetists taught by traditional methods. Twenty anaesthetists were allocated randomly to either the video or traditional training group. A graduated training programme was used in which the first stage was an introduction to techniques and apparatus and the second stage was practice on an airway model. During the third stage, rhinoscopy, pharyngoscopy and laryngoscopy were performed on anaesthetized patients whose lungs were ventilated via an orotracheal tube. A maximum time of 6 min was allowed for completion of laryngoscopy. Trainees aimed to perform five endoscopies in less than 60 s before moving on to the next stage. During the fourth stage, they carried out five traditional nasotracheal intubations (plus two video-controlled intubations for the video group) on apnoeic, anaesthetized patients. The mean number of endoscopies required (11.7 vs 21.8), mean total endoscopy time (21.5 vs 63.1 min) and mean number of failed endoscopies (0.8 vs 3.9) were significantly less in the video group. All the video-controlled intubations were successful. There was no significant difference between the number of successful traditional intubations in the two groups (90% video, 92% traditional). CCTV appears to enhance substantially the rate of acquisition of fibreoptic nasotracheal intubation skills.

Role of endogenous retroviruses as mutagens: the hairless mutation of mice.

We have developed an experimental approach to distinguish the 40-60 endogenous C-type proviruses of mice and to determine their association with well characterized developmental and physiological mutations. The hairless (hr) mutation causes a variety of pleiotropic effects. Using oligonucleotide probes specific for different classes of murine leukemia virus, we have identified and cloned a provirus present in HRS/J hr/hr animals but absent in HRS/J +/+. Genetic analyses showed perfect concordance between the hr phenotype and the presence of the provirus in a number of inbred and congenic strains of mice. Molecular analysis of a haired revertant established the causal relationship since it revealed the excision of most of the proviral genome leaving behind one long terminal repeat. These findings show that virus integration caused the hairless mutation and point to the utility of naturally occurring retroviral integrations for accessing the genome of the mouse.

Relationship between retroviral DNA integration and gene expression.

Although retroviruses can integrate their DNA into a large number of sites in the host genome, factors controlling the specificity of integration remain controversial and poorly understood. To assess the effects of transcriptional activity on integration in vivo, we created quail cell clones containing a construct with a minigene cassette, whose expression is controlled by the papilloma virus E2 protein. From these clones we derived transcriptionally active subclones expressing the wild-type E2 protein and transcriptionally silent subclones expressing a mutant E2 protein that binds its target DNA but is unable to activate transcription. By infecting both clones and subclones with avian leukosis virus and using a PCR-based assay to determine viral DNA integration patterns, we were able to assess the effects of both protein binding and transcriptional activity on retroviral DNA integration. Contrary to the hypothesis that transcriptional activity enhances integration, we found an overall decrease in integration into our gene cassette in subclones expressing the wild-type E2 protein. We also found a decrease in integration into our gene cassette in subclones expressing the mutant E2 protein, but only into the protein binding region. Based on these findings, we propose that transcriptionally active DNA is not a preferred target for retroviral integration and that transcriptional activity may in fact be correlated with a decrease in integration.

Structure and expression of the hairless gene of mice.

The hairless mutation of mice was caused by insertion of a murine leukemia virus. Starting with sequences flanking the provirus, a series of overlapping clones surrounding the viral integration site were obtained. By using a combination of sequencing, PCR, and exon-trapping techniques, the hairless gene was identified. It encodes a predicted protein of 1182 amino acids, including a potential zinc-finger domain. The expression patterns of the gene closely reflect the phenotype of animals carrying the hairless mutation.

Molecular basis for attenuation of neurovirulence of a yellow fever Virus/Japanese encephalitis virus chimera vaccine (ChimeriVax-JE).

A yellow fever virus (YFV)/Japanese encephalitis virus (JEV) chimera in which the structural proteins prM and E of YFV 17D are replaced with those of the JEV SA14-14-2 vaccine strain is under evaluation as a candidate vaccine against Japanese encephalitis. The chimera (YFV/JEV SA14-14-2, or ChimeriVax-JE) is less neurovirulent than is YFV 17D vaccine in mouse and nonhuman primate models (F. Guirakhoo et al., Virology 257:363-372, 1999; T. P. Monath et al., Vaccine 17:1869-1882, 1999). Attenuation depends on the presence of the JEV SA14-14-2 E protein, as shown by the high neurovirulence of an analogous YFV/JEV Nakayama chimera derived from the wild JEV Nakayama strain (T. J. Chambers, A. Nestorowicz, P. W. Mason, and C. M. Rice, J. Virol. 73:3095-3101, 1999). Ten amino acid differences exist between the E proteins of ChimeriVax-JE and the YFV/JEV Nakayama virus, four of which are predicted to be neurovirulence determinants based on various sequence comparisons. To identify residues that are involved in attenuation, a series of intratypic YFV/JEV chimeras containing either single or multiple amino acid substitutions were engineered and tested for mouse neurovirulence. Reversions in at least three distinct clusters were required to restore the neurovirulence typical of the YFV/JEV Nakayama virus. Different combinations of cluster-specific reversions could confer neurovirulence; however, residue 138 of the E protein (E(138)) exhibited a dominant effect. No single amino acid reversion produced a phenotype significantly different from that of the ChimeriVax-JE parent. Together with the known genetic stability of the virus during prolonged cell culture and mouse brain passage, these findings support the candidacy of this experimental vaccine as a novel live-attenuated viral vaccine against Japanese encephalitis.

Effects of AvGard treatment on the microbiological flora of poultry carcases.

1. The efficiency of the AvGard (or Assur-Rince in the USA) trisodium phosphate poultry carcase decontamination process was evaluated during both manual and industrial trials against total aerobic mesophilic count (TAMC), thermotolerant coliforms, Pseudomonas, Enterobacteriaceae, Campylobacter, Listeria monocytogenes and Salmonella. 2. The TSP treatment proved to have significant effects on the bacterial decontamination of poultry neck skin, lowering the contamination by a factor of about 10 for TAMC and of 100 for Coliform and Pseudomonas. 3. Numeration of Salmonella with an innovative miniaturised most probable number method has proved that the effect upon these micro-organisms was also close to 2 log10 reduction. 4. The effect of TSP treatment on the ecological balance of psychrotrophic bacterial flora was also investigated to study the origin of the shelf-life flora of treated carcases (Pseudomonas being reduced to the limit of detection) and to ascertain whether L. monocytogenes might gain a competitive advantage. In fact AvGard reduced the number of L. monocytogenes on poultry carcases. 5. As a consequence of the virtual elimination of the Pseudomonas usually present, Brochothrix thermosphacta became the main species responsible for putrefaction. 6. Because the growth rate of Brochothrix thermosphacta was greater than that of L. monocytogenes at refrigeration temperature, it was considered that putrefaction would occur before the emergence of large numbers of L. monocytogenes.