Differential distribution of orexin-A and orexin-B immunoreactivity in the rat brain and spinal cord

The orexins are recently identified appetite-stimulating hypothalamic peptides. We used immunohistochemistry to map orexin-A and orexin-B immunoreactivity in rat brain, spinal cord, and some peripheral tissues. Orexin-A- and orexin-B-immunoreactive cell bodies were confined to the lateral hypothalamic area and perifornical nuclei. Orexin-A-immunoreactive fibers were densely distributed in the hypothalamus, septum, thalamus, locus coeruleus, spinal cord, and near the ventricles, but absent from peripheral sites investigated. In contrast, orexin-B-immunoreactive fibers were distributed sparsely in the hypothalamus. Orexin cells are strategically sited to contribute to feeding regulation, but their widespread projections suggest that orexins have other physiological roles.

Orexin A activates locus coeruleus cell firing and increases arousal in the rat

The localization of orexin neuropeptides in the lateral hypothalamus has focused interest on their role in ingestion. The orexigenic neurones in the lateral hypothalamus, however, project widely in the brain, and thus the physiological role of orexins is likely to be complex. Here we describe an investigation of the action of orexin A in modulating the arousal state of rats by using a combination of tissue localization and electrophysiological and behavioral techniques. We show that the brain region receiving the densest innervation from orexinergic nerves is the locus coeruleus, a key modulator of attentional state, where application of orexin A increases cell firing of intrinsic noradrenergic neurones. Orexin A increases arousal and locomotor activity and modulates neuroendocrine function. The data suggest that orexin A plays an important role in orchestrating the sleep-wake cycle.

Nutrition: a necessary adjunct to hospital care?

Good nutrition is undoubtedly central to optimum health and to the recovery from illness yet research and clinical surveys repeatedly demonstrate an unacceptably high incidence of malnutrition in hospital patients in whom it delays recovery, increases the incidence of complications and significantly increases the cost of treatment; the human cost is inestimable.

A systematic approach to erectile dysfunction in the cardiovascular patient: a consensus statement

Sexual activity is no more stressful to the heart when compared with a number of other natural daily activities, e.g. walking one mile on the level in 20 minutes. The cardiac risk of sexual activity in patients diagnosed with cardiovascular disease is minimal in properly assessed and advised patients. Erectile dysfunction (ED) is common, affecting 10% of men aged 40-70 years and increases in frequency with age. ED and cardiovascular disease share many of the same risk factors and often coexist. ED in the diagnosed cardiovascular patient should be identified by routine questioning in general practice. Modern therapies can restore a sexual relationship in the majority of patients with ED and can lead to a substantial improvement in quality of life. The majority of patients assessed to be at low or intermediate cardiac risk, as defined later in this paper (Table 4), can be effectively managed in primary care. Primary care treatment for ED in patients defined as high risk can be initiated following a specialist opinion and/or confirmation that the patient's cardiovascular condition is stabilised. There is no evidence that currently licensed treatments for ED add to the overall cardiovascular risk in patients with or without diagnosed cardiovascular disease.

Benchmarking pathology services: implementing a longitudinal study

This paper details the benchmarking process and its application to the activities of pathology laboratories participating in a benchmark pilot study [the Royal College of Pathologists of Australasian (RCPA) Benchmarking Project]. The discussion highlights the primary issues confronted in collecting, processing, analysing and comparing benchmark data. The paper outlines the benefits of engaging in a benchmarking exercise and provides a framework which can be applied across a range of public health settings. This information is then applied to a review of the development of the RCPA Benchmarking Project. Consideration is also given to the nature of the preliminary results of the project and the implications of these results to the on-going conduct of the study.

Facing the issue of dependence: some implications from the literature for the hospice and hospice nurses

Research and clinical practice suggest that dependence upon others causes distress to those with a life-threatening illness and that the hospice may serve to reinforce feelings of loss of autonomy. Hospice nurses can contribute to good care and act therapeutically to maximize an individual's potential for independent activity where this is possible and desirable. However, literature from other contexts demonstrates variability in the extent to which this is achieved. This paper outlines the problem of dependence in those with a life threatening illness. Therapeutic nursing is explored in relation to issues which may arise in a hospice context, potential relationships between therapeutic nursing and partnership are noted, particularly with regard to the possible meanings of dependence which for some individuals comes to be apprehensively associated with impending death.

Two-site immunoassays for osteoclastic tartrate-resistant acid phosphatase based on characterization of six monoclonal antibodies

Tartrate-resistant acid phosphatase (TRAP), an enzyme expressed in bone-resorbing osteoclasts, is secreted into the circulation during bone resorption. We used six monoclonal antibodies (MAbs) to optimize direct two-site fluoroimmunoassays for determining serum TRAP concentrations. Four of the MABs, 1F1, 2H1, 4E6, and 5C1, were raised against recombinant human TRAP, and the other two, O1A and J1B, against human bone TRAP. 2H1, J1B, and O1A appeared to be highly specific for TRAP. 1F1 and 4E6 were poor in recognizing bone TRAP and were not useful in the assay. 5C1, while having a good affinity for the bone enzyme, was not specific. Serum TRAP is relatively stable, because 7 days of storage of serum samples at 4 degreesC and -20 degreesC or five thawing-freezing cycles, did not change the TRAP concentration detected using the two-site assays. All studied assays detected an increase in serum TRAP concentrations of postmenopausal women compared with premenopausal women, the difference being highest with MAB pairs 2H1-5C1 and O1A-J1B. These results suggest that serum TRAP may be a useful bone resorption marker, and the MAB pairs 2H1-5C1 and O1A-J1B may be useful in determining the bone resorption rate.

Analysis of uroliths from cats and dogs in New Zealand, 1993-96

AIMS

Canine and feline uroliths were analysed to determine the prevalence of particular types of urolith and the dog breeds at risk.

METHODS

Three hundred and sixty-nine uroliths recovered from 316 dogs and 53 cats between November 1993 and December 1996 were analysed by X-ray diffraction, and by infrared spectrometry where X-ray diffraction alone was non-diagnostic.

RESULTS

Bitches of small breeds especially Welsh corgi and Bichon frise, were most frequently affected. Struvite was the most common urolith (204 dogs). Oxalate (60 dogs) was the second most prevalent urolith identified, followed by cystine (24 dogs). The breeds producing cystine calculi were: Dalmatian, Bassett hound, Borzoi, Newfoundland, Shetland sheepdog, Labrador, Chihuahua, Fox terrier, English bulldog, Bichon frise, Doberman pinscher, Border collie. Silica uroliths were identified for the first time in New Zealand. All feline uroliths were struvite.

CONCLUSION

The results are useful in determining the prevalence of specific types of urolith in New Zealand and the breeds at risk of forming them.

Processing of the Alzheimer's disease amyloid precursor protein in Pichia pastoris: immunodetection of alpha-, beta-, and gamma-secretase products

betaA4 (Abeta) amyloid peptide, a major component of Alzheimer's disease (AD) plaques, is a proteolytic product of the amyloid precursor protein (APP). Endoproteases, termed beta- and gamma-secretase, release respectively the N- and C-termini of the peptide. APP default secretion involves cleavage within the betaA4 domain by alpha-secretase. To study the conservation of APP processing in lower eukaryotes, the yeast Pichia pastoris was transfected with human APP695 cDNA. In addition to the full-length integral transmembrane protein found in the cell lysate, soluble/secreted APP (sAPP) was detected in the culture medium. Most sAPP comprised the N-terminal moiety of betaA4 and corresponds to sAPPalpha, the product of alpha-secretase. The culture medium also contained minor secreted forms detected by a monoclonal antibody specific for sAPPbeta (the ectodomain released by beta-secretase cleavage). Analysis of the cell lysates with specific antibodies also detected membrane-associated C-terminal fragments corresponding to the products of alpha and beta cleavages. Moreover, immunoprecipitation of the culture medium with three antibodies directed at distinct epitopes of the betaA4 domain yielded a 4 kDa product with the same electrophoretic mobility as betaA4 synthetic peptide. These results suggest that the alpha-, beta-, and gamma-secretase cleavages are conserved in yeast and that P. pastoris may offer an alternative to mammalian cells to identify the proteases involved in the generation of AD betaA4 amyloid.

Antibodies to TR2 (herpesvirus entry mediator), a new member of the TNF receptor superfamily, block T cell proliferation, expression of activation markers, and production of cytokines

TR2 (TNFR-related 2) is a recently identified member of the TNFR family with homology to TNFRII. We have demonstrated previously that TR2 mRNA is expressed in resting and activated human T cells and that TR2-Ig partially inhibits an allogeneic mixed leukocyte proliferation response. We now characterize TR2 further by the use of specific mAbs. Flow-cytometry analysis using TR2 mAbs confirmed that resting PBL express high levels of cell surface TR2, and that TR2 is widely expressed on all freshly isolated lymphocyte subpopulations. However, stimulation of purified T cells with either PHA or PHA plus PMA resulted in decreased surface expression within 48 h of activation before returning to resting levels at 72 h. TR2 mAbs inhibited CD4+ T cell proliferation in response to stimulation by immobilized CD3 or CD3 plus CD28 mAbs. Assay of culture supernatants by ELISA showed inhibition of TNF-alpha, IFN-gamma, IL-2, and IL-4 production, which, for IL-2 and TNF-alpha was also confirmed by intracellular cytokine staining. Furthermore, expression of activation markers on CD4+ T cells, including CD25, CD30, CD69, CD71, and OX40 (CD134), was inhibited. TR2 mAbs inhibited proliferation in a three-way MLR, and a response to soluble recall Ag, tetanus toxoid. In conclusion, these results suggest that TR2 is involved in the activation cascade of T cell responses and TR2 mAbs prevent optimal T cell proliferation, cytokine production, and expression of activation markers.

Xerostomia: aetiology and management in cancer patients

Although oral complications are common sequelae of cancer/cancer treatment, only sporadic research is published in the literature. It is clear that 'routine' oral hygiene measures are inadequate; a little time and effort may, however, reduce oral discomfort. This is particularly true in the case of xerostomia, which is often thought to be a relatively minor symptom with few deleterious effects. Many patients, however, find xerostomia a significant cause of distress, and for this reason alone, health care professionals require knowledge and appreciation of the pathology and aetiology of the condition and approaches to its management. This paper reviews the physiology of salivation and the aetiology of xerostomia and considers the ways in which the condition can be managed.

Promoting oral health in institutionalised older adults: a nursing perspective

Current demographic trends necessitate that increased attention be paid to problems arising in the older population. One such area relates to the oral cavity, which may be affected by both the effects of aging and the effects of disease and illness. Yet the evidence shows a significant lack of adequate oral care, which may create major problems for affected individuals, causing oral and dental problems that may, in turn, predispose to nutritional deficiencies, communication difficulties and devastating dental disease (Ogle, 1982). This paper reviews the literature pertaining to this complex subject, concluding that although nurses have an important role in providing effective oral care for the institutionalised patient, it is difficult to identify appropriate techniques, agents and tools with which to provide such care. Further research in this field is undoubtedly needed.