The metabolic syndrome and schizophrenia: the latest evidence and nursing guidelines for management

The introduction of second-generation antipsychotic drugs for the treatment of schizophrenia has provided significant benefits for clients experiencing this disorder. While they have been found effective in reducing psychotic symptoms, there is evidence that these drugs are also linked with a group of side effects commonly known as the metabolic syndrome. Mental health nurses are well positioned to prevent, detect and/or manage the development of this problematic constellation of symptoms. Guidelines for practice can be useful in prevention and management of the syndrome and enhance nursing care of clients who are taking second-generation antipsychotics.

Gene therapy progress and prospects: Duchenne muscular dystrophy

Duchenne muscular dystrophy (DMD) is a severe muscle wasting disorder affecting 1/3500 male births. There is currently no effective treatment, but gene therapy approaches are offering viable avenues for treatment development. The last 10 years have seen the development of a number of strategies and tools for muscle gene therapy. However, the major hurdle has been the inability to deliver vectors at high enough efficiency via a systemic route. The last 2-3 years (reviewed here) have seen unrivalled progress in efficient systemic delivery of viral and non-viral gene transfer agents and antisense oligonucleotides. This progress, coupled with the successful completion of the first gene therapy clinical trial for DMD, has led to three more clinical trials planned for the immediate future.

Clinical assessment and core outcome variables are poor predictors of hip arthritis diagnosed by MRI in juvenile idiopathic arthritis

OBJECTIVES

To compare the diagnostic performance of clinical assessment against magnetic resonance imaging (MRI) diagnosed hip arthritis in a juvenile idiopathic arthritis (JIA) population. To determine the clinical and serological predictors of MRI diagnosed hip arthritis.

METHODS

A total of 34 JIA patients with established disease (mean disease duration 6.3 yrs) had their hip MRIs scored for features of active hip arthritis and hip damage. Results were compared with clinical variables (disease subtype, history of hip pain, core outcome variables (COV)) and the clinician's assessment of active hip arthritis.

RESULTS

MRI features of active hip arthritis were found in 45 hips (70%) and hip damage in 36 hips (56%). Clinical assessment had fair agreement with MRI scoring of active arthritis in patients with disease duration <4 yrs (kappa score 0.38, P = 0.045). Clinical assessment had a sensitivity of 25.7% and specificity of 91% for detecting MRI diagnosed arthritis. Of the core outcome variables only erythrocyte sedimentation rate predicted inflammation detected on MRI (r = 0.44, P = 0.014).

CONCLUSIONS

The association between the clinician's assessment, core outcome variables and MRI findings in this study was limited. This indicates that clinical and laboratory findings are inadequate diagnostic tools for the assessment of hip arthritis when compared with MRI as the gold standard.

Adaptation of healthy mastication to factors pertaining to the individual or to the food

Mastication is a physiological process controlled by the central nervous system and modulated by inputs from the mouth. Both the intrinsic characteristics of the subject and the extrinsic characteristics of the chewed food are responsible for variations of the masticatory function. Age, gender and dental state constitute the most studied intrinsic factors whereas hardness, rheological characteristics such as plasticity or elasticity, and food size are the better known extrinsic factors. These factors cause physiological adaptations which can occur during individual cycles or the whole sequence of mastication. Electromyographic and jaw movements (kinematic) recordings are commonly used to study mastication, from which, several variables can be measured. Vertical and lateral amplitudes and, velocities of jaw movements, are only given by kinematic recordings. Bioelectrical activities per cycle or per sequence are closely linked to masticatory forces and are measured from electromyographic recordings. Number of cycles, sequence duration and masticatory frequency can be measured from both types of recordings. The objective of this review is to provide an overview of the variations of the measured masticatory variables that occur when mastication adapts to changes in characteristics of the individual or the food.

Antipsychotic drugs and pregnant or breastfeeding women: the issues for mental health nurses

Antipsychotic drugs and pregnant or breastfeeding women: the issues for mental health nurses Mental illness can affect up to 10% of pregnant women, and women with a pre-existing psychiatric condition are more likely to experience a relapse of symptoms during pregnancy. Antipsychotic drugs are an important part of the treatment of psychotic illnesses; however, their safety with pregnant or breastfeeding women has not been fully established. Given that these drugs will be ordered for pregnant or breastfeeding women diagnosed with a psychosis or with a pre-existing psychiatric condition, it is imperative that mental health nurses and others administering the drugs, or caring for those taking the drugs, be aware of their consequences. A review of the available evidence, albeit at times contradictory, is presented along with a discussion of the implications for mental health nurses. Recommendations for consideration when administering or counselling women regarding the use of antipsychotic drugs in pregnancy or when breastfeeding, are also included.

Guidelines and adenosine dosing in supraventricular tachycardia

This retrospective review of present practice of administration of adenosine by paediatricians shows that current guidelines recommend starting doses that are effective in only 9% of infants and children.

Anosmia is very common in the Lewy body variant of Alzheimer's disease

BACKGROUND

Olfactory abnormalities are reported in Alzheimer's disease and Parkinson's disease. Anosmia appears to be common in dementia with Lewy bodies but not in pure Alzheimer's disease.

OBJECTIVE

To determine whether anosmia improves discrimination between the Lewy body variant (LBV) of Alzheimer's disease and "pure" Alzheimer's disease.

METHODS

106 cases of necropsy confirmed pure Alzheimer's disease (n = 89) or LBV (n = 17) were reviewed. All had received butanol odour threshold testing. Anosmia was defined as a score < or = 1.0 on a 0-9 point scale. Logistic regression analysis was used to model potential predictors (for example, parkinsonism, smoking, hallucinations) of neuropathological diagnosis and anosmia.

RESULTS

LBV cases had an increased prevalence of anosmia (65%) compared with Alzheimer's disease (23%; odds ratio (OR) = 6.3, p = 0.00045), or normal elderly people (6.7%). Within the dementia cases, the negative predictive value (92%) and specificity (78%) of anosmia were both good; sensitivity for detecting LBV was 65%, but the positive predictive value (PPV) was only 35%. Logistic regression models showed anosmia (OR = 5.4, p = 0.005) and visual hallucinations (OR = 7.3, p = 0.007) were strong independent predictors of Lewy body pathology. When anosmia was added as a core feature to consensus diagnostic criteria for probable Lewy body dementia, five additional cases of LBV were detected (29% increased sensitivity), but with four additional false positives (1% increased discrimination, 4% decreased specificity, 33% decreased PPV).

CONCLUSIONS

Anosmia is very common in LBV. Adding anosmia as a core feature improved sensitivity for detecting LBV, but did not improve discrimination between Alzheimer's disease and LBV owing to a concomitant increase in false positives.

Clostridium difficile: a questionnaire survey of laboratory practice in England, Wales, and Northern Ireland

Since January 2004, the incidence of Clostridium difficile associated disease (CDAD) has been monitored by a systematic, national, laboratory surveillance system. This system incorporates the recommendations of a body of experts, the National Clostridium difficile Standards Group, which was convened in 2002 to advise the Department of Health (DoH). The recommendations of the group were informed by a questionnaire survey of current practice, and the results of that survey have been used to assess the implications of the recommendations on laboratory practice. Large variability was found as to the specimens selected, tested, and reported on for C. difficile. Standardisation of the diagnosis and reporting of CDAD is desirable and necessary to increase understanding of its epidemiology.

MRI of the marrow in the paediatric skeleton

Magnetic resonance imaging (MRI) has greatly advanced evaluation of marrow diseases of the paediatric skeleton. As with many other aspects of paediatric radiology it is important to recognize the normal variations in the appearance of the marrow that occur in the growing child. These normal variations need to be differentiated from diseases and conditions that affect the marrow. This review describes the normal changes that occur in children with age, and the appearances of the pathological changes seen in infection, infiltration, haematological disorders, transplantation and radiation therapy.

The circumstances of adults with a psychotic disorder

This article presents some findings about adults with a psychotic disorder who were identified in the OPCS surveys of psychiatric morbidity. The main aim of the analysis was to identify characteristics associated with differences in the circumstances and health-related behaviour of adults aged 16-64 with psychosis. The analysis covers people who were identified by the various criteria used on the surveys as having a psychotic illness and who were considered to be living in private households. First we describe briefly the survey methods used and how diagnoses of psychosis were derived. We then present results from four topic areas covered in the analysis. These are: use of medication, use of health services, difficulties with activities of daily living, and social support.

A Gr receptor is required for response to the sugar trehalose in taste neurons of Drosophila

We recently identified from the Drosophila genome database a large family of G protein-coupled receptor genes, the Gr genes, and predicted that they encode taste receptors on the basis of their structure and specificity of expression. The expression of Gr genes in gustatory neurons has subsequently been confirmed and 56 family members have been reported. Here we provide functional evidence that one Gr gene, Gr5a, encodes a taste receptor required for response to the sugar trehalose. In two different mutants that carry deletions in Gr5a, electrophysiological and behavioral responses to trehalose were diminished but the response to sucrose was unaffected. Transgenic rescue experiments showed that Gr5a confers response to trehalose. The results correlate a particular taste ligand with a Gr receptor and indicate a role for G protein-mediated signaling in the transduction of sweet taste in Drosophila.

Point-of-care testing. Cost issues and impact on hospital operations

Advancing technology has allowed for the migration of laboratory testing from the central laboratory to the near-patient setting, leading ideally to a shorter therapeutic turnaround time. This potential benefit, however, comes with a price tag. Assessing the cost-benefit ratio on a per test basis cannot effectively be done in a generalized manner, because each hospital must evaluate this with respect to its own unique circumstances. There are, however, certain outcomes, such as decreased LOS and decreased blood-product usage that, if achieved, far outweigh the cost of POCT, justifying its use. Any hospital attempting to implement POCT must also realize that hospital operations are affected by such use and that adjustments and careful laboratory oversight are required.

Odor coding in the Drosophila antenna

Odor coding in the Drosophila antenna is examined by a functional analysis of individual olfactory receptor neurons (ORNs) in vivo. Sixteen distinct classes of ORNs, each with a unique response spectrum to a panel of 47 diverse odors, are identified by extracellular recordings. ORNs exhibit multiple modes of response dynamics: an individual neuron can show either excitatory or inhibitory responses, and can exhibit different modes of termination kinetics, when stimulated with different odors. The 16 ORN classes are combined in stereotyped configurations within seven functional types of basiconic sensilla. One sensillum type contains four ORNs and the others contain two neurons, combined according to a strict pairing rule. We provide a functional map of ORNs, showing that each ORN class is restricted to a particular spatial domain on the antennal surface.

Distinct molecular mechanisms and divergent endocytotic pathways of AMPA receptor internalization

Internalization of postsynaptic AMPA receptors depresses excitatory transmission, but the underlying dynamics and mechanisms of this process are unclear. Using immunofluorescence and surface biotinylation, we characterized and quantified basal and regulated AMPA receptor endocytosis in cultured hippocampal neurons, in response to synaptic activity, AMPA and insulin. AMPA-induced AMPA receptor internalization is mediated in part by secondary activation of voltage-dependent calcium channels, and in part by ligand binding independent of receptor activation. Although both require dynamin, insulin- and AMPA-induced AMPA receptor internalization are differentially dependent on protein phosphatases and sequence determinants within the cytoplasmic tails of GluR1 and GluR2 subunits. AMPA receptors internalized in response to AMPA stimulation enter a recycling endosome system, whereas those internalized in response to insulin diverge into a distinct compartment. Thus, the molecular mechanisms and intracellular sorting of AMPA receptors are diverse, and depend on the internalizing stimulus.

Evaluation of a centrifuge with rapid turnaround time for the preparation of plasma samples for measurement of common STAT markers on the ACS: 180 system

Reported is the evaluation of a new centrifugation method, Statspin, that addresses both time and sample separation integrity. The method can successfully separate the plasma fraction from the cellular material in 2 minutes as compared to 20 minutes for the conventional centrifuge method. The Statspin, combined with the ACS:180 system, can generate test results in less than 30 minutes, exclusive of transport to the laboratory. This study demonstrated that the combined technologies offer timing-saving improvements for clinical laboratories offering STAT immunoassays for cardiac markers, endocrine molecules, and therapeutic drugs.

Capsaicin-stimulated release of substance P from cultured dorsal root ganglion neurons: involvement of two distinct mechanisms

Capsaicin, the pungent component of "hot" chili peppers, selectively activates a distinct population of primary sensory neurons responsive to noxious stimuli. Many of these fibres express neuropeptides including the tachykinin, substance P. Using cultured dorsal root ganglion neurons, we found that capsaicin (10 microM) stimulated a 2-fold increase in release of substance P in the absence of extracellular Ca(2+). Elevated potassium (75 mM) was unable to induce release under these conditions. The introduction of Ca(2+) enhanced capsaicin-induced release and brought about a robust response to potassium. Preincubation of cells with botulinum neurotoxin A (100 nM) completely blocked potassium-induced release but the capsaicin response, in the absence of Ca(2+), was unaffected. However, toxin treatment dramatically reduced capsaicin-stimulated release in the presence of Ca(2+). It is concluded that capsaicin induces release of substance P from dorsal root ganglion neurons via two mechanisms, one requiring extracellular Ca(2+) and the intact synaptosomal-associated protein 25 kDa (SNAP-25), and the other independent of extracellular Ca(2+) and not involving SNAP-25.

Use of a dual monoclonal solid phase and a polyclonal detector to create an immunoassay for the detection of human cardiac troponin I

OBJECTIVES

We report the development of a fully automated, random access, chemiluminescent immunoassay, for the detection of human cardiac Troponin I (cTnI) in serum and plasma for use on the ACS:180(R) System.

DESIGN AND METHODS

This assay format uses a combination of two monoclonal antibodies covalently coupled to paramagnetic (PMP) particles as a solid phase and an affinity purified polyclonal antibody, specific to the N-terminal domain of cTnI (peptide-3 region) labeled with a chemiluminescent compound as the detector antibody. The assay offers excellent low-end sensitivity and precision.

RESULTS

No interferences are observed from by blood components such as HAMA and drugs used in cardiac therapy. Patient samples tested on the ACS:180 cTnI assay showed good correlation with the Stratus cTnI assay (ACS: cTnI = 1. 02*Stratus + 0.05 g/L, r = 0.96, n = 1170).

CONCLUSION

Paired with the other ACS:180 cardiac assays, myoglobin and CKMBII, the ACS:180 system now offers an excellent panel of cardiac assay for use in rapid and accurate diagnosis of a myocardial event.

Development of an in vitro bioassay for Clostridium botulinum type B neurotoxin in foods that is more sensitive than the mouse bioassay

A novel, in vitro bioassay for detection of the botulinum type B neurotoxin in a range of media was developed. The assay is amplified by the enzymic activity of the neurotoxin's light chain and includes the following three stages: first, a small, monoclonal antibody-based immunoaffinity column captures the toxin; second, a peptide substrate is cleaved by using the endopeptidase activity of the type B neurotoxin; and finally, a modified enzyme-linked immunoassay system detects the peptide cleavage products. The assay is highly specific for type B neurotoxin and is capable of detecting type B toxin at a concentration of 5 pg ml(-1) (0.5 mouse 50% lethal dose ml(-1)) in approximately 5 h. The format of the test was found to be suitable for detecting botulinum type B toxin in a range of foodstuffs with a sensitivity that exceeds the sensitivity of the mouse assay. Using highly specific monoclonal antibodies as the capture phase, we found that the endopeptidase assay was capable of differentiating between the type B neurotoxins produced by proteolytic and nonproteolytic strains of Clostridium botulinum type B.