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C Shaw

Publications and source records attributed to C Shaw.

At least 127 records · Page 7Linked to original sources
PubMed1996

Amnesia and recognition memory: a re-analysis of psychometric data.

The present study compared the recognition memory deficit in different groups of amnesics using scores from a standard test. The data, taken from a literature search, came from 33 studies reporting the performance of amnesic subjects on the recognition memory test (RMT) [77]. A total of 112 amnesic subjects were grouped according to their pathology. In addition, the analysis included subjects with schizophrenia, amygdala damage, or frontal lobe damage. Of these three nonamnesic groups, only the frontal lobe subjects were impaired on both RMT subtests, while the schizophrenics showed a disproportionate impairment for the recognition of faces. The amygdala subjects were also poor at face recognition. Among the amnesic groups, those subjects likely to have multiple sites of pathology (e.g. Korsakoff amnesics, post-encephalitics) were found to be the most impaired on the RMT. In contrast, those amnesics with more focal, limbic lesions in the hippocampus, fornix, or mamillary body region showed much milder deficits on the RMT task, some performing at normal levels. Despite their apparent sparing of recognition, the overall severity of amnesia in those subjects with limbic lesions appeared comparable to that in the remaining amnesics. These findings indicate that deficits on both subtests of the RMT are a frequent but not inevitable component of anterograde amnesia. They also point to a distinct subgroup of amnesias associated with selective damage in the hippocampus or its diencephalic targets, in which there is a relative sparing of recognition under certain test conditions.

Adolescent↗
PubMed1996

The Pharmacology of Nematode FMRFamide-related Peptides.

FMRFamide-related peptides (FaRPs) are the largest known family of invertebrate neuropeptides. Immunocytochemical screens of nematode tissues using antisera raised to these peptides have localized extensive FaRP-immunostaining to their nervous systems. Although 21 FaRPs have been isolated and sequenced from extracts of free-living and parasitic nematodes, available evidence indicates that other FaRPs await discovery. While our knowledge of the pharmacology of these native nematode neuropeptides is extremely limited, reports on their physiological activity in nematodes are ever increasing. All the nematode FaRPs examined so far have been found to have potent and varied actions on nematode neuromuscular activity. It is only through the extensive pharmacological and physiological assessment of the tissue, cell and receptor interactions of these peptidic messengers that an understanding of their activity on nematode neuromusculature will be possible. In this review, Aaron Maule and colleagues examine the current understanding of the pharmacology of nematode FaRPs.

Journal Article↗
PubMed1996

Insect neuropeptide F (NPF)-related peptides: isolation from Colorado potato beetle (Leptinotarsa decemlineata) brain.

Two novel neuropeptides with neuropeptide F (NPF)-like immunoreactivity have been isolated from brain extracts of the Colorado potato beetle. Purification was achieved primarily by use of reverse phase chromatography including initial C-18 Sep-Pak cartridges and 4 subsequent analytical HPLC columns. Combined data from automated Edman degradation, immunochemical analysis, u.v. absorbance and mass spectrometry led to the elucidation of their full primary structures. The deduced sequences are: Ala-Arg-Gly-Pro-Gln-Leu-Arg-Leu-Arg-Phe-NH2 (ARGPQLRLRFamide) and Ala-Pro-Ser-Leu-Arg-Leu-Arg-Phe-NH2 (APSLRLRFamide). On the basis of their primary structure both peptides can be appended to the invertebrate group of neuropeptide Y (NPY)-like peptides, generally referred to as NPFs. We suggest these peptides to be designated Led-NPF-1 and Led-NPF-2.

Amino Acid Sequence↗
PubMed1996

Cholinergic, serotoninergic and peptidergic components of the nervous system of Discocotyle sagittata (Monogenea:Polyopisthocotylea).

Cholinergic, serotoninergic (5-HT) and peptidergic neuronal pathways have been demonstrated in both central and peripheral nervous systems of adult Discocotyle sagittata, using enzyme histochemistry and indirect immunocytochemistry in conjunction with confocal scanning laser microscopy. Antisera to 2 native flatworm neuropeptides, neuropeptide F and the FMRFamide-related peptide (FaRP), GNFFRFamide, were employed to detect peptide immunoreactivity. The CNS is composed of paired cerebral ganglia and connecting dorsal commissure, together with several paired longitudinal nerve cords. The main longitudinal nerve cords (lateral, ventral and dorsal) are interconnected at intervals by a series of annular cross-connectives, producing a ladder-like arrangement typical of the platyhelminth nervous system. At the level of the haptor, the ventral cords provide nerve roots which innervate each of the 9 clamps. Cholinergic and peptidergic neuronal organisation was similar, but distinct from that of the serotoninergic components. The PNS and reproductive system are predominantly innervated by peptidergic neurones.

Animals↗
PubMed1996

Conscious sedation: a multidisciplinary team approach.

The administration of intravenous conscious sedation for patients undergoing minor procedures has increased in many settings throughout health care. Recognizing this, managers are challenged to develop policies to standardize the quality of patient care delivery. Consumer interest and knowledge in health care has increased dramatically in the last few years. Their demands for decreased cost, increased technology, and quality of care have compelled health care organizations to adopt quality management models. Quality improvement teams were developed to look at processes crossing departmental boundaries. Teams facilitate dialogue, understanding, and knowledge, and use the scientific method to design, streamline, and improve processes. The authors share strategies for policy development using a 7-step quality improvement process with a multidisciplinary team approach.

Clinical Competence↗
PubMed1996

Neuropeptides and their evolution.

Neuropeptides are ubiquitous signalling molecules in all metazoans possessing nervous systems, from the simple nerve nets of the cnidarians to the immensely complex systems of mammals. While the discipline of peptide neuroendocrinology was born through the study of higher vertebrates, there now exists a plethora of information regarding neuropeptides and peptidic regulatory factors in invertebrates. Such phylogenetic studies have revealed that peptidic neurotransmission is of early evolutionary origin and that, while invertebrates have nervous systems which are simpler in terms of nerve cell number and organisation when compared with vertebrates, the complexity of the peptidic 'vocabulary' of invertebrate neurones is of a similar order of magnitude. Most research on invertebrate neuropeptides has been directed towards representative members of groups such as the insects and molluscs and it is only in recent years that efforts have been focused on the helminths (platyhelminths and nematodes). Here, the putative origins of peptidic transmitters is discussed and the current state of knowledge on helminth neuropeptides is reviewed. In order to place the study of helminth neuropeptides in an historical and conceptual perspective, methodological development and conceptual modifications in the disciplines of vertebrate and higher invertebrate peptide neuroendocrinology have been summarised.

Animals↗
PubMed1996

Isolation, localization, and bioactivity of the FMRFamide-related neuropeptides GYIRFamide and YIRFamide from the marine turbellarian Bdelloura candida.

Two FMRFamide-related neuropeptides, GYIRFamide and YIRFamide, were isolated from the marine turbellarian Bdelloura candida. The peptides elicited a dose-dependent contraction of isolated turbellarian muscle fibers, and both were more potent than FMRFamide. Structure-activity studies, using a range of analogues of the tetrapeptide amide, indicated that the structure of the endogenous peptides was optimal for peak activity. Immunocytochemistry, using an autologous antiserum, revealed a widespread distribution of peptide immunoreactivity within central and peripheral neurons and their processes. This study indicates an important role for GYIRFamide and YIRFamide in the control of neuromuscular function in turbellarians.

Amino Acid Sequence↗
PubMed1996

Accreditation programs for hospitals: funding and operation.

Accreditation is a formal process by which an authorized body assesses and recognizes an individual, an organization (like a hospital), a program, or a group as complying with requirements such as standards or criteria. This article analyses and compares the activity and funding of six health care accrediting bodies which operate in five different countries, and which in 1994, accredited over 5000 health centres. The data included in this article could be useful for other institutions who wish to commence accreditation programmes for health care organizations.

Accreditation↗
PubMed1996

A case report of paroxysmal dystonic choreoathetosis due to hypoglycaemia induced by an insulinoma.

Hypoglycaemia due to an insulinoma can mimic acute disorders of cognition, consciousness, epilepsy, transient ischaemia, or psychosis, and chronic disorders of dementia and neuropathy. Misdiagnosis and delay in treatment are common and prolonged hypoglycaemia can lead to permanent neurological deficit or fatal coma. A 27 year old woman with hypoglycaemia induced by an insulinoma presented with features typical of paroxysmal non-kinesiogenic dystonic choreoathetosis. Striatal dysfunction as a consequence of hypoglycaemia has rarely been described. Insulinoma is a readily treatable condition that should be considered in the differential diagnosis of a paroxysmal movement disorder.

Adult↗
PubMed1995

Isolation of AF2 (KHEYLRFamide) from Caenorhabditis elegans: evidence for the presence of more than one FMRFamide-related peptide-encoding gene.

Numerous FMRFamide-related peptides (FaRPs) have been isolated and sequenced from extracts of free-living and parasitic nematodes. The most abundant FaRP identified in ethanolic/methanolic extracts of the parasitic forms, Ascaris suum and Haemonchus contortus and from the free-living nematode, Panagrellus redivivus, was KHEYLRFamide (AF2). Analysis of the nucleotide sequences of cloned FaRP-precursor genes from C. elegans and, more recently, Caenorhabditis vulgaris identified a series of related FaRPs which did not include AF2. An acid-ethanol extract of Caenorhabditis elegans was screened radioimmunometrically for the presence of FaRPs using a C-terminally directed FaRP antiserum. Approximately 300 pmols of the most abundant immunoreactive peptide was purified to homogeneity and 30 pmols was subjected to Edman degradation analysis and gas-phase sequencing. The unequivocal primary structure of the heptapeptide, Lys-His-Glu-Tyr-Leu-Arg-Phe-NH2 (AF2) was determined following a single gas-phase sequencing run. The molecular mass of the peptide was determined using a time-of-flight mass spectrometer and was found to be 920 (MH+)+, which was consistent with the theoretical mass of C-terminally amidated AF2. These results indicate that C. elegans possesses more than one FaRP gene.

Amino Acid Sequence↗
PubMed1995

Localisation, quantitation, and characterisation of neuropeptide F- and FMRFamide-immunoreactive peptides in turbellarians and a monogenean: a comparative study.

Over the past decade it has become clear that the nervous systems of platyhelminths are both complex and highly developed, particularly in peptidergic elements. The central position of an ancestral flatworm in the evolution of the Bilateria has placed a greater importance on the study of modern flatworms. Using antisera generated to the C-terminal region of platyhelminth neuropeptide F and the molluscan neuropeptide, FMRFamide, in immunocytochemistry at both light and ultrastructural levels, immunoreactivities have been localised within the nervous systems of three species of triclad turbellarians, Dugesia lugubris, Dendrocoelum lacteum, and Polycelis nigra, and one species of monogenean trematode, Diclidophora merlangi. Extensive immunostaining was obtained with both antisera throughout the central and peripheral nervous systems of all species studied, but intensity and abundance was significantly greater in the turbellarians. Indirect electron-immunogold labeling demonstrated that immunoreactivity to both neuropeptides was often colocalised in neurosecretory vesicles, although discrete populations of vesicles were also observed. Radioimmunoassay of extracts of all species confirmed that neuropeptide F immunoreactivity was consistently more abundant than FMRFamide immunoreactivity, and that the levels of both in the three turbellarians were several orders of magnitude greater than those found in the monogenean. Chromatographic analyses of turbellarian extracts revealed that neuropeptide F and FMRFamide immunoreactivities were attributable to different peptides. These data imply that the neuropeptidergic systems systems of turbellarians are considerably more extensive than those of monogeneans, and would suggest that a regression has occurred in the latter as a consequence of the adoption of a mere sedentary parasitic lifestyle.

Animals↗
PubMed1995

GYIRFamide: a novel FMRFamide-related peptide (FaRP) from the triclad turbellarian, Dugesia tigrina.

Modern phylogenetic schemes propose a free-living turbellarian-like organism as the ancestor of all Bilateria, including chordates. While neuropeptides are now known to be of ancient origin within the nervous systems of invertebrates, the neuropeptides of turbellarians remain virtually unexplored. Here we report the primary structure of an FMRFamide-related pentapeptide, Gly-Tyr-Ile-Arg-Phe amide (GYIRFamide), isolated from an acidified ethanolic extract of the aquatic triclad turbellarian, Dugesia tigrina. Previously, we reported the primary structure, RYIRFamide, from the New Zealand terrestrial turbellarian, Artioposthia triangulata, widely regarded as a most atypical species. However, the present data implies a high degree of primary structural conservation between the FMRFamide-related peptides of both species despite the zoogeographical isolation of the New Zealand form for several hundred million years. In addition, while authentic FMRFamide itself has been identified in many molluscs and a few annelids, the current data would suggest that turbellarian analogues are typically pentapeptides with an X-Y-I-R-Famide motif. A protein/peptide database search revealed that the sequence GYIRF is contained within the primary structure of several bacterial Ni/Fe hydrogenase B-type cytochrome subunits and several proliferating cell nuclear antigens (cyclins) from plants.

Amino Acid Sequence↗
PubMed1995

A proliferative adult human oligodendrocyte progenitor.

The failure of oligodendrocytes to sustain repair of demyelinated axons contributes to the cumulative neurological disability which characterizes multiple sclerosis. In the rodent, transplanted neonatal glial progenitors efficiently remyelinate gliotoxic lesions. Proliferative bipotential progenitors are also present in the adult rat, but have not hitherto been identified in adult human tissue. Here we demonstrate cells in cultures of adult human temporal lobe which are morphologically and immunocytochemically identical to rate progenitors, are bipotential, and exhibit an astrocyte-driven proliferative response. The identification of an adult human oligodendrocyte progenitor is the first step towards developing interventional strategies for promoting repair of demyelinated lesions in patients with multiple sclerosis.

Astrocytes↗
PubMed1995

Immunohistochemical localization of a Shaker-related voltage-gated potassium channel protein in Schistosoma mansoni (Trematoda: Digenea).

We have recently isolated a cDNA (SKv1.1) encoding a Shaker-related K+ channel from the human parasitic trematode Schistosoma mansoni. In order to better understand the functions of SKv1.1 protein, the distribution of SKv1.1 protein in adult S. mansoni was analyzed by immunohistochemistry using a region-specific antibody. SKv1.1 proteins were widely expressed in the nervous and muscular systems. The strongest immunoreactivity (IR) was observed in the nervous system of both male and female. In the nervous system, IR for SKv1.1 proteins was localized in cell bodies and nerve fibers of the anterior ganglia, the central commissure, and the main nerve cords. IR was also observed in the dorsal and the ventral peripheral nerve nets, fine nerve fibers entering into a variety of structures such as the dorsal tubercles, longitudinal and ventral muscle fibers, and oral and ventral suckers. In the muscular system, SKv1.1 proteins were localized to the longitudinal, circular, and ventral muscle fibers of male as well as in isolated muscle fibers where native A-type K+ currents were measured. Moderate IR was also seen in a large number of cell bodies in the parenchyma. These results indicate that SKv1.1 protein may play an important role in the regulation of the excitability of neurons and muscle cells of S. mansoni.

Amino Acid Sequence↗