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Soffin EM, Evans ML, Gill CH, Harries MH, Benham CD, Davies CH. SB-334867-A antagonises orexin mediated excitation in the locus coeruleus. Neuropharmacology 2002; 42:127-33. [PMID: 11750922 DOI: 10.1016/s0028-3908(01)00156-3] [Citation(s) in RCA: 74] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Electrophysiological recordings from identified noradrenergic locus coeruleus (LC) neurones in rat brain slices have revealed that the orexins can cause direct and reversible depolarisation of the postsynaptic membrane. Whilst it is known that the membrane depolarisation produced by orexin-A can triple the firing rate of spontaneously active LC neurones, quantitative pharmacological analysis that determines the receptor subtype(s) mediating the orexinergic response has not yet been performed. Here we demonstrate that the effects of orexin-A are five-fold more potent than orexin-B on LC neuronal excitability. We show further that the orexin receptor antagonist SB-334867-A inhibits the effects of both agonists with pK(B) values similar to those calculated for human OX1 receptors expressed in CHO cells. Finally, we found no evidence for tonic activation of OX1 receptors in LC noradrenergic neurones despite electron microscopic evidence that orexin terminals directly contact these neurones. These data demonstrate that SB-334867-A is a useful tool compound with which to study the physiology of OX1 receptors.
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Young D, Ma J, Cherkerzian S, Froimowitz MP, Ennulat DJ, Cohen BM, Evans ML, Lange N. Automated identification of Fos expression. Biostatistics 2001; 2:351-64. [PMID: 12933544 DOI: 10.1093/biostatistics/2.3.351] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The concentration of Fos, a protein encoded by the immediate-early gene c-fos, provides a measure of synaptic activity that may not parallel the electrical activity of neurons. Such a measure is important for the difficult problem of identifying dynamic properties of neuronal circuitries activated by a variety of stimuli and behaviours. We employ two-stage statistical pattern recognition to identify cellular nuclei that express Fos in two-dimensional sections of rat forebrain after administration of antipsychotic drugs. In stage one, we distinguish dark-stained candidate nuclei from image background by a thresholding algorithm and record size and shape measurements of these objects. In stage two, we compare performance of linear and quadratic discriminants, nearest-neighbour and artificial neural network classifiers that employ functions of these measurements to label candidate objects as either Fos nuclei, two touching Fos nuclei or irrelevant background material. New images of neighbouring brain tissue serve as test sets to assess generalizability of the best derived classification rule, as determined by lowest cross-validation misclassification rate. Three experts, two internal and one external, compare manual and automated results for accuracy assessment. Analyses of a subset of images on two separate occasions provide quantitative measures of inter- and intra-expert consistency. We conclude that our automated procedure yields results that compare favourably with those of the experts and thus has potential to remove much of the tedium, subjectivity and irreproducibility of current Fos identification methods in digital microscopy.
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Calver AR, Medhurst AD, Robbins MJ, Charles KJ, Evans ML, Harrison DC, Stammers M, Hughes SA, Hervieu G, Couve A, Moss SJ, Middlemiss DN, Pangalos MN. The expression of GABA(B1) and GABA(B2) receptor subunits in the cNS differs from that in peripheral tissues. Neuroscience 2001; 100:155-70. [PMID: 10996466 DOI: 10.1016/s0306-4522(00)00262-1] [Citation(s) in RCA: 128] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
GABA(B) receptors are G-protein-coupled receptors that mediate the slow and prolonged synaptic actions of GABA in the CNS via the modulation of ion channels. Unusually, GABA(B) receptors form functional heterodimers composed of GABA(B1) and GABA(B2) subunits. The GABA(B1) subunit is essential for ligand binding, whereas the GABA(B2) subunit is essential for functional expression of the receptor dimer at the cell surface. We have used real-time reverse transcriptase-polymerase chain reaction to analyse expression levels of these subunits, and their associated splice variants, in the CNS and peripheral tissues of human and rat. GABA(B1) subunit splice variants were expressed throughout the CNS and peripheral tissues, whereas surprisingly GABA(B2) subunit splice variants were neural specific. Using novel antisera specific to individual GABA(B) receptor subunits, we have confirmed these findings at the protein level. Analysis by immunoblotting demonstrated the presence of the GABA(B1) subunit, but not the GABA(B2) subunit, in uterus and spleen. Furthermore, we have shown the first immunocytochemical analysis of the GABA(B2) subunit in the brain and spinal cord using a GABA(B2)-specific antibody. We have, therefore, identified areas of non-overlap between GABA(B1) and GABA(B2) subunit expression in tissues known to contain functional GABA(B) receptors. Such areas are of interest as they may well contain novel GABA(B) receptor subunit isoforms, expression of which would enable the GABA(B1) subunit to reach the cell surface and form functional GABA(B) receptors.
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Anderson RA, Evans ML, Ellis GR, Graham J, Morris K, Jackson SK, Lewis MJ, Rees A, Frenneaux MP. The relationships between post-prandial lipaemia, endothelial function and oxidative stress in healthy individuals and patients with type 2 diabetes. Atherosclerosis 2001; 154:475-83. [PMID: 11166782 DOI: 10.1016/s0021-9150(00)00499-8] [Citation(s) in RCA: 179] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Post-prandial lipaemia (PPL) is a factor in atherogenesis and results in reversible endothelial dysfunction in healthy individuals. Oxidative stress and triglyceride (TG)-rich lipoproteins have been implicated. Type 2 diabetes (NIDDM) results in exaggerated PPL. We attempted to delineate the mechanisms of PPL induced, endothelial dysfunction (EF) and oxidative stress in 12 NIDDM and 12 matched healthy subjects. Subjects underwent a fat tolerance test, with endothelial function assessed by flow-mediated vasodilatation and oxidative stress measured by venous lipid-derived free radicals ex vivo and lipid peroxidation products over the postprandial phase. Fasting TG, post-prandial hypertriglyceridaemia and the TG enrichment of all lipoproteins was significantly greater in NIDDM. Post-prandial endothelial function inversely correlated with fasting HDL-C (r=-0.84, P=0.001) in both the control and NIDDM groups. The deterioration in EF in the NIDDM group also correlated with TG enrichment of VLDL and LDL. PPL in both groups also resulted in increased oxidative stress. The increment in free radicals correlated with TG enrichment of VLDL in both groups and was, therefore, greater in NIDDM. Thus, PPL -- with the production of TG-enrichment of VLDL -- results in endothelial dysfunction by an oxidative stress mechanism in both groups. The magnitude is greater in NIDDM. Fasting HDL-C appears to contribute to the protection of the endothelium against this phenomenon. Hence, exaggerated PPL associated with reduced HDL-C may be important in the pathogenesis of vascular disease, particularly in NIDDM.
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Charles KJ, Evans ML, Robbins MJ, Calver AR, Leslie RA, Pangalos MN. Comparative immunohistochemical localisation of GABA(B1a), GABA(B1b) and GABA(B2) subunits in rat brain, spinal cord and dorsal root ganglion. Neuroscience 2001; 106:447-67. [PMID: 11591450 DOI: 10.1016/s0306-4522(01)00296-2] [Citation(s) in RCA: 104] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
GABA(B) receptors are G-protein-coupled receptors mediating the slow onset and prolonged synaptic actions of GABA in the CNS. The recent cloning of two genes, GABA(B1) and GABA(B2), has revealed a novel requirement for GABA(B) receptor signalling. Studies have demonstrated that the two receptor subunits associate as a GABA(B1)/GABA(B2) heterodimer to form a functional GABA(B) receptor. In this study we have developed polyclonal antisera specific to two splice variants of the GABA(B1) subunit, GABA(B1a) and GABA(B1b), as well as an antiserum to the GABA(B2) subunit. Using affinity-purified antibodies derived from these antisera we have mapped out the distribution profile of each subunit in rat brain, spinal cord and dorsal root ganglion. In brain the highest areas of GABA(B1a), GABA(B1b) and GABA(B2) subunit expression were found in neocortex, hippocampus, thalamus, cerebellum and habenula. In spinal cord, GABA(B1) and GABA(B2) subunits were expressed in the superficial layers of the dorsal horn, as well as in motor neurones in the deeper layers of the ventral horn. GABA(B) receptor subunit immunoreactivity in dorsal root ganglion suggested that expression of GABA(B1b) was restricted to the large diameter neurones, in contrast to GABA(B1a) and GABA(B2) subunits which were expressed in both large and small diameter neurones. Although expression levels of GABA(B1) and GABA(B2) subunits varied we found no areas in which GABA(B1) was expressed in the absence of GABA(B2). This suggests that most, if not all, GABA(B1) immunoreactivity may represent functional GABA(B) receptors. Although our data are in general agreement with functional studies, some discrepancies in GABA(B1) subunit expression occurred with respect to other immunohistochemical studies. Overall our data suggest that GABA(B) receptors are widely expressed throughout the brain and spinal cord, and that GABA(B1a) and GABA(B1b) subunits can associate with GABA(B2) to form both pre- and post-synaptic receptors.
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Cutler DJ, Morris R, Evans ML, Leslie RA, Arch JR, Williams G. Orexin-A immunoreactive neurons in the rat hypothalamus do not contain neuronal nitric oxide synthase (nNOS). Peptides 2001; 22:123-8. [PMID: 11179606 DOI: 10.1016/s0196-9781(00)00364-8] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The lateral hypothalamic area (LHA), a key site involved in the central control of feeding and energy homeostasis, contains populations of neurons that produce the orexin peptides or nitric oxide, two chemical factors that increase food intake. In this study, we used immunohistochemistry to investigate the possibility that rat LHA neurons co-express orexin-A and neuronal nitric oxide synthase (nNOS). The orexin-A and nNOS cell populations in the LHA showed extensive overlap without co-localization, and no evidence of direct anatomic contact was found. The finding that LHA neurons do not co-localize orexin-A and nNOS may suggest that the actions of the orexins and nitric oxide on food intake are mediated via independent mechanisms, however, nitric oxide is a diffusible molecule and could potentially affect the activity of orexin neurons via a non-synaptic mechanism.
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Cai XJ, Evans ML, Lister CA, Leslie RA, Arch JR, Wilson S, Williams G. Hypoglycemia activates orexin neurons and selectively increases hypothalamic orexin-B levels: responses inhibited by feeding and possibly mediated by the nucleus of the solitary tract. Diabetes 2001; 50:105-12. [PMID: 11147774 DOI: 10.2337/diabetes.50.1.105] [Citation(s) in RCA: 164] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Orexins are novel appetite-stimulating peptides expressed in the lateral hypothalamic area (LHA), and their expression is stimulated by hypoglycemia in fasted rats. We investigated activation of orexin and other neurons during insulin-induced hypoglycemia using the immediate early gene product Fos. Insulin (50 U/kg) lowered plasma glucose by >50% after 5 h and stimulated feeding sixfold compared with saline-injected controls. Hypoglycemic rats allowed to feed and normoglycemic controls both showed sparse Fos-positive (Fos+) neurons in the LHA and the paraventricular nucleus (PVN) and arcuate nucleus (ARC) and showed none in the nucleus of the solitary tract (NTS), which relays visceral feeding signals to the LHA. In the LHA, total numbers of Fos+ neurons were comparable in fed hypoglycemic and control groups (60 +/- 6 vs. 52 +/- 4 cells/mm2, P > 0.05), as were Fos+ neurons immunoreactive for orexin (1.4 +/- 0.4 vs. 0.6 +/- 0.4 cells/mm2, P > 0.05). By contrast, hypoglycemic rats that were fasted showed significantly more Fos+ nuclei in the LHA (96 +/- 10 cells/mm2, P < 0.05, vs. both other groups) and Fos+ orexin neurons (8.4 +/- 3.3 cells/mm2, P < 0.001, vs. both other groups). They also showed two- to threefold more Fos+ nuclei (P < 0.001) in the PVN and ARC than both fed hypoglycemic rats and controls and showed strikingly abundant Fos+ neurons in the NTS and dorsal motor nucleus of the vagus. In parallel studies, whole hypothalamic orexin-A levels were not changed in hypoglycemic rats, whether fasted or freely fed, whereas orexin-B levels were 10-fold higher in hypoglycemic fasted rats than in control and hypoglycemic fed groups. These data support our hypothesis that orexin neurons are stimulated by falling glucose levels but are readily inhibited by signals related to nutrient ingestion and suggest that they may functionally link with neuronal activity in the NTS. Orexin-A and -B may play specific roles in behavioral or neuroendocrine responses to hypoglycemia.
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Wolverton C, Mullen JL, Ishikawa H, Evans ML. Two distinct regions of response drive differential growth in Vigna root electrotropism. PLANT, CELL & ENVIRONMENT 2000; 23:1275-1280. [PMID: 11706855 DOI: 10.1046/j.1365-3040.2000.00629.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Although exogenous electric fields have been reported to influence the orientation of plant root growth, reports of the ultimate direction of differential growth have been contradictory. Using a high-resolution image analysis approach, the kinetics of electrotropic curvature in Vigna mungo L. roots were investigated. It was found that curvature occurred in the same root toward both the anode and cathode. However, these two responses occurred in two different regions of the root, the central elongation zone (CEZ) and distal elongation zone (DEZ), respectively. These oppositely directed responses could be reproduced individually by a localized electric field application to the region of response. This indicates that both are true responses to the electric field, rather than one being a secondary response to an induced gravitropic stimulation. The individual responses differed in the type of differential growth giving rise to curvature. In the CEZ, curvature was driven by inhibition of elongation, whereas curvature in the DEZ was primarily due to stimulation of elongation. This stimulation of elongation is consistent with the growth response of the DEZ to other environmental stimuli.
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Juturi JV, Maghfoor I, Doll DC, Evans ML. A case of biliary carcinoid presenting with pancreatitis and obstructive jaundice. Am J Gastroenterol 2000; 95:2973-4. [PMID: 11051379 DOI: 10.1111/j.1572-0241.2000.00819.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
A 43-yr-old man presented to the clinic with abdominal pain, jaundice, nausea, and vomiting and weight loss over a 6-month period. Physical exam was unrevealing other than mild epigastric tenderness. A computed tomographic scan of the abdomen revealed a mass in the head of the pancreas, which was resected at laparotomy by a Whipple's procedure. The histology showed a biliary tract carcinoid tumor. The patient had normal hydroxy-indole-acetic acid (HIAA) levels throughout. There has been no evidence of disease or tumor recurrence at 3.5 yr of follow up.
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Abstract
Using available computer graphics software programs, a novice can develop a presentation. Going beyond the basics, however, requires knowledge of the use of the elements of design: fonts, colors, and graphics. This article describes how to select fonts and colors and provides guidelines for use of pictures and graphs. Guidelines for use of default settings and templates, and considerations related to the use of animation, sound, and projection are included. Examples are provided to demonstrate important points and creating a polished, professional product.
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Evans ML, Pernet A, Lomas J, Jones J, Amiel SA. Delay in onset of awareness of acute hypoglycemia and of restoration of cognitive performance during recovery. Diabetes Care 2000; 23:893-7. [PMID: 10895837 DOI: 10.2337/diacare.23.7.893] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
OBJECTIVE To examine the time course for the onset of, and recovery from, acute hypoglycemia in healthy subjects. RESEARCH DESIGN AND METHODS Eight healthy male volunteers were studied on 2 occasions in random order using a hyperinsulinemic (1.5 mU x kg(-1) x min(-1)) glucose clamp technique. During control studies, euglycemia (5.01 +/- 0.02 mmol/l) was maintained for 225 +/- 3 min. On the other occasion, after a euglycemic baseline period, arterialized plasma glucose was allowed to fall rapidly to 2.65 +/- 0.02 mmol/l, then maintained at this nadir for 90 min before euglycemia was rapidly restored. RESULTS Cognitive function assessed by a battery of sensitive tests (4-choice reaction time, Stroop word, and color-word test) became impaired immediately at onset of hypoglycemia (P < 0.05 for all in the hypoglycemic study vs. those in the euglycemic study). Counterregulatory hormone responses (epinephrine, norepinephrine, glucagon, cortisol, and growth hormone) and symptomatic awareness of hypoglycemia (assessed by a questionnaire) were relatively delayed, being detected 20 min after the onset of hypoglycemia. There was no diminution (adaptation) of any responses, cognitive, humoral, or symptomatic, during sustained hypoglycemia. During recovery, the 4-choice reaction time continued to be abnormal even after resolution of symptomatic awareness (P = 0.025). CONCLUSIONS During hypoglycemia, cognitive performance may become impaired before symptomatic awareness. During recovery from hypoglycemia, recovery of cognitive function lags behind the restoration of glucose levels and resolution of symptoms. Our findings have implications for the design of studies examining experimental hypoglycemia and need to be investigated in people with diabetes.
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Ray AM, Owen DE, Evans ML, Davis JB, Benham CD. Caspase inhibitors are functionally neuroprotective against oxygen glucose deprivation induced CA1 death in rat organotypic hippocampal slices. Brain Res 2000; 867:62-9. [PMID: 10837798 DOI: 10.1016/s0006-8993(00)02230-7] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We have explored the neuroprotective efficacy of the cell penetrant caspase inhibitor, Ac-YVAD-cmk, in a hippocampal slice model of neuronal cell death induced by oxygen and glucose deprivation. Organotypic hippocampal slice cultures were prepared from 8 to 10-day-old rats and maintained for 10 to 12 days in vitro. Pre-treatment with Ac-YVAD-cmk prior to 45 min oxygen and glucose deprivation was neuroprotective as measured by propidium iodide uptake, with an EC(50) between 1 and 10 micromol/l. Ac-YVAD-cmk was also able to preserve synaptic function in the organotypic hippocampal slice cultures 24 h after oxygen and glucose deprivation. Ac-YVAD-cmk prevented the increase in histone-associated DNA fragmentation induced by oxygen and glucose deprivation. Interleukin-1beta did not reverse the protective effect of Ac-YVAD-cmk, and interleukin-1 receptor antagonist alone was not protective. These results show that caspase inhibitors are neuroprotective in a hippocampal slice culture system, using structural, biochemical and electrophysiological endpoints, and that this effect is not a result of inhibition of interleukin-1beta production.
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Mullen JL, Wolverton C, Ishikawa H, Evans ML. Kinetics of constant gravitropic stimulus responses in Arabidopsis roots using a feedback system. PLANT PHYSIOLOGY 2000; 123:665-70. [PMID: 10859196 PMCID: PMC59034 DOI: 10.1104/pp.123.2.665] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/1999] [Accepted: 02/09/2000] [Indexed: 05/18/2023]
Abstract
The study of gravitropism is hindered by the fact that as a root responds, the gravitational stimulus changes. Using a feedback system to connect a rotating stage platform to a video digitizer system, we were able to maintain a constant angle of gravistimulation to Arabidopsis roots for long time periods. The rate of curvature approximated the sine rule for angles of stimulation between 20 degrees and 120 degrees. For a given angle of stimulation, the rate of curvature also remained constant, with no observed diminishment of the response. Although previous reports of Arabidopsis root gravitropism suggest latent periods of approximately 30 min, using a smooth mechanical stage to reorient the root, we observed a mean time lag of approximately 10 min. This more rapid onset of curvature can, in part, be explained by reduced mechanical perturbation during the process of gravistimulation. This suggests that mechanical stimulation associated with rapid root re-orientation may confound investigations of early gravitropic events.
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Wolverton C, Mullen JL, Aizawa S, Yoshizaki I, Kamigaichi S, Mukai C, Shimazu T, Fukui K, Evans ML, Ishikawa H. Inhibition of root elongation in microgravity by an applied electric field. UCHU SEIBUTSU KAGAKU 2000; 14:58-63. [PMID: 11543422 DOI: 10.2187/bss.14.58] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Roots grown in an applied electric field demonstrate a bidirectional curvature. To further understand the nature of this response and its implications for the regulation of differential growth, we applied an electric field to roots growing in microgravity. We found that growth rates of roots in microgravity were higher than growth rates of ground controls. Immediately upon application of the electric field, root elongation was inhibited. We interpret this result as an indication that, in the absence of a gravity stimulus, the sensitivity of the root to an applied electric stimulus is increased. Further space experiments are required to determine the extent to which this sensitivity is shifted. The implications of this result are discussed in relation to gravitropic signaling and the regulation of differential cell elongation in the root.
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Abstract
A 56-year-old man initially presented to his family physician with tingling in the fingertips of his left hand. A chest radiograph revealed a left upper lobe mass. Local resection found a soft tissue osteogenic sarcoma. This is a report of a rare case of primary pulmonary osteogenic sarcoma.
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Wolverton C, Mullen JL, Aizawa S, Yoshizaki I, Kamigaichi S, Mukai C, Shimazu T, Fukui K, Evans ML, Ishikawa H. Inhibition of root elongation in microgravity by an applied electric field. JOURNAL OF PLANT RESEARCH 1999; 112:493-496. [PMID: 11543178 DOI: 10.1007/pl00013905] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Roots grown in an applied electric field demonstrate a bidirectional curvature. To further understand the nature of this response and its implications for the regulation of differential growth, we applied an electric field to roots growing in microgravity. We found that growth rates of roots in microgravity were higher than growth rates of ground controls. Immediately upon application of the electric field, root elongation was inhibited. We interpret this result as an indication that, in the absence of a gravity stimulus, the sensitivity of the root to an applied electric stimulus is increased. Further space experiments are required to determine the extent to which this sensitivity is shifted. The implications of this result are discussed in relation to gravitropic signaling and the regulation of differential cell elongation in the root.
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Cutler DJ, Morris R, Sheridhar V, Wattam TA, Holmes S, Patel S, Arch JR, Wilson S, Buckingham RE, Evans ML, Leslie RA, Williams G. Differential distribution of orexin-A and orexin-B immunoreactivity in the rat brain and spinal cord. Peptides 1999; 20:1455-70. [PMID: 10698122 DOI: 10.1016/s0196-9781(99)00157-6] [Citation(s) in RCA: 186] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
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.
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Hagan JJ, Leslie RA, Patel S, Evans ML, Wattam TA, Holmes S, Benham CD, Taylor SG, Routledge C, Hemmati P, Munton RP, Ashmeade TE, Shah AS, Hatcher JP, Hatcher PD, Jones DN, Smith MI, Piper DC, Hunter AJ, Porter RA, Upton N. Orexin A activates locus coeruleus cell firing and increases arousal in the rat. Proc Natl Acad Sci U S A 1999; 96:10911-6. [PMID: 10485925 PMCID: PMC17982 DOI: 10.1073/pnas.96.19.10911] [Citation(s) in RCA: 888] [Impact Index Per Article: 35.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
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.
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Evans ML, Chan PJ, Patton WC, King A. Sperm artificially exposed to antisperm antibodies show altered deoxyribonucleic acid. J Assist Reprod Genet 1999; 16:443-9. [PMID: 10478325 PMCID: PMC3455493 DOI: 10.1023/a:1020525726674] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
PURPOSE Our purpose was to assess sperm deoxyribonucleic acid (DNA) integrity after exposure to antisperm antibodies. METHODS Donor semen were divided and exposed to sera containing IgG, IgA, and IgM antisperm antibodies. Untreated portions served as the control. After incubation (1 hr, 23 degrees C), the sperm were centrifuge-washed, resuspended, and incubated (23 degrees C) for 2, 5, 7, or 9 days. Acridine orange staining and kinematic parameters were measured. The sentinel (17q21 from D17S855) and beta-globin genes were amplified and analyzed using denaturing gradient gel electrophoresis. RESULTS Sperm preexposed to antisperm antibodies had deleted sentinel gene on days 7 and 9. The beta-globin gene was intact. There were no differences in acridine orange staining. CONCLUSIONS Sperm artificially exposed to antisperm antibodies resulted in a subtle deletion of genetic material. The DNA alteration process was slow and was undetectable at the gross level. More studies are needed to confirm the findings and determine whether DNA repair mechanisms can reverse the damage.
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Caeser M, Evans ML, Benham CD. Lack of effect of the novel anticonvulsant SB-204269 on voltage-dependent currents in neurones cultured from rat hippocampus. Neurosci Lett 1999; 271:57-60. [PMID: 10471213 DOI: 10.1016/s0304-3940(99)00514-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
The novel anticonvulsant SB-204269 inhibits epileptiform afterdischarges induced by high K+ in rat hippocampal slices. Its effects on voltage-gated Na+ currents, measured from cultured hippocampal neurones using whole cell patch clamp, were compared to the effects of existing anticonvulsants. SB-204269 produced no significant tonic block of Na+ currents nor any voltage-dependent and frequency-dependent block at doses 50 to 500 fold higher than its anticonvulsant EC50 of 0.2 microM. In contrast, lamotrigine, phenytoin and carbamazepine at 50 microM, blocked Na+ currents in a voltage-dependent manner. SB-204269 also had no effect on action potential discharges evoked by elevating external K+. These data suggest that direct blockade of voltage-gated channels does not contribute to the anticonvulsant properties of SB-204269 and further support the hypothesis that this compound has a novel mechanism of action.
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Oberg KC, Robles AE, Ducsay CA, Rasi CR, Rouse GA, Childers BJ, Evans ML, Kirsch WM, Hardesty RA. Endoscopic intrauterine surgery in primates: overcoming technical obstacles. Surg Endosc 1999; 13:420-6. [PMID: 10094762 DOI: 10.1007/s004649901004] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Current protocols for fetal surgery require cesarean section and partial fetal extraction, both of which impart significant risks to the mother and fetus. Endoscopic fetal surgery is less invasive and will likely reduce some of these risks, but the technical difficulties and feasibility in a primate model have yet to be explored fully. Four pregnant baboons (95 days gestation) were anesthetized, their uteruses exposed via an abdominal incision, and blunt-tipped flanged endoscopic ports inserted. Amniotic fluid was removed, and warmed saline was infused to dilate the uterus. To evaluate instrumentation and wound closure, the tip of the snout was externalized and bilateral cleft lip-like defects made. The lips were then endoscopically repaired by suture (Endostitch, U.S. Surgical) or unique nonpenetrating clips (VCS, U.S. Surgical). The saline was then removed, amniotic fluid returned, and the ports carefully removed. After 4 weeks, the fetuses were delivered and evaluated. Eight cleft lip-like defects were successfully repaired in all four cases. Operative time averaged 83 min. No infections, amniotic leaks, or adhesions developed. Survival was 50% with two fetuses delivering within 48 hours postoperatively: one from preterm labor, the other with fetal demise from retroperitoneal hemorrhage after operative blunt abdominal trauma. We demonstrate the feasibility of endoscopic fetal surgery in primates. The use of blunt-tipped flanged ports provides a fluid tight seal and allows appropriate closure of the fetal membranes, but requires laparotomy and uterine exposure. Distension of the uterus with warmed saline affords a larger operating field, enhancing visualization and instrumentation of the fetus. Grasping the fetus through the exposed uterus gives excellent control for repair. However, such control is also needed in a percutaneous approach. Further instrumentation development is needed to accomplish similar control for the percutaneous approach.
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Bumgarner SD, Evans ML. Clinical care map for the ambulatory laparoscopic cholecystectomy patient. J Perianesth Nurs 1999; 14:12-6. [PMID: 10358510 DOI: 10.1016/s1089-9472(99)90003-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Shortened hospital stays, expectations of quick recovery, and rapid turn-around times in surgical services challenge perioperative nurses to be creative and innovative providers of essential and appropriate patient education. Nurses need approaches that enable them to meet these challenges. One such approach is the adaptation of a clinical care map to the development of a perioperative patient care guide. This article describes the rationale behind the use of this approach and its application to the education of the patient undergoing laparoscopic cholecystectomy. Steps in the process are described. Nurses can use these steps to develop patient care guides suited to their specific practice setting.
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Mullen JL, Turk E, Johnson K, Wolverton C, Ishikawa H, Simmons C, Söll D, Evans ML. Root-growth behavior of the Arabidopsis mutant rgr1. Roles of gravitropism and circumnutation in the waving/coiling phenomenon. PLANT PHYSIOLOGY 1998; 118:1139-45. [PMID: 9847088 PMCID: PMC34730 DOI: 10.1104/pp.118.4.1139] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/1998] [Accepted: 09/11/1998] [Indexed: 05/18/2023]
Abstract
In this study we investigated the kinetics of the gravitropic response of the Arabidopsis mutant rgr1 (reduced root gravitropism). Although the rate of curvature in rgr1, which is allelic to axr4, was smaller than in the wild type (ecotype Wassilewskija), curvature was initiated in the same region of the root, the distal elongation zone. The time lag for the response was unaffected in the mutant; however, the gravitropic response of rgr1 contained a feature not found in the wild type: when roots growing along the surface of an agar plate were gravistimulated, there was often an upward curvature that initiated in the central elongation zone. Because this response was dependent on the tactile environment of the root, it most likely resulted from the superposition of the waving/coiling phenomenon onto the gravitropic response. We found that the frequency of the waving pattern and circumnutation, a cyclic endogenous pattern of root growth, was the same in rgr1 and in the wild type, so the waving/coiling phenomenon is likely governed by circumnutation patterns. The amplitudes of these oscillations may then be selectively amplified by tactile stimulation to provide a directional preference to the slanting.
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Evans ML, Martin ML, Winslow EH. Nursing care and patient satisfaction. Am J Nurs 1998; 98:57-9. [PMID: 9875184] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
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Evans ML, Dick MJ, Shields DR, Shook DM, Smith MB. Postpartum sleep in the hospital. Relationship to taking-in and taking-hold. Clin Nurs Res 1998; 7:379-89. [PMID: 9919094 DOI: 10.1177/105477389800700405] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
This descriptive, correlational study examined the relationship of sleep in the hospital to the new mother's progression through Rubin's phases of taking-in and taking-hold in 120 women who had delivered vaginally. The Martell and Mitchell Postpartum Questionnaire, which measured taking-in and taking-hold, was completed the evening of delivery and the following two mornings. The Verran and Snyder-Halpern Visual Analog Sleep Scale was completed each morning. Both taking-in and taking-hold were present on the evening of delivery. There were small decreases in taking-in and small increases in taking-hold between the evening of delivery and the first morning. Sleep disturbance was high, and sleep effectiveness was low, on the first evening. Neither sleep measure was a predictor of change in taking-in or taking-hold. Findings indicate that taking-in and taking-hold are both present on the day of delivery and that increases in taking-hold take place despite high levels of sleep disturbance.
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