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Schneider-Utaka AK, Hanes S, Boughton CK, Hartnell S, Thabit H, Mubita WM, Draxlbauer K, Poettler T, Hayes J, Wilinska ME, Mader JK, Narendran P, Leelarathna L, Evans ML, Hovorka R, Hood KK. Patient-reported outcomes for older adults on CamAPS FX closed loop system. Diabet Med 2023; 40:e15126. [PMID: 37171467 DOI: 10.1111/dme.15126] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/03/2022] [Revised: 04/25/2023] [Accepted: 05/02/2023] [Indexed: 05/13/2023]
Abstract
AIMS Use of the CamAPS FX hybrid closed loop (CL) system is associated with improved time in range and glycated haemoglobin A1c across the age span, but little is known about its effects on patient-reported outcomes (PROs). METHODS This open-label, randomized, multi-site study compared CamAPS FX to sensor-augmented pump (SAP) in a sample of older adults (≥60 years) with type 1 diabetes (T1D). Thirty-five older adults completed PROs surveys at the start of the study and after each period of 16 weeks using either CL or SAP. At the end of the study, 19 participated in interviews about their experiences with CL. RESULTS Results examining the 16 weeks of CL use showed that the overall Diabetes Distress Scale score and two subscales (powerlessness and physician distress) improved significantly along with trust on the Glucose Monitoring Satisfaction Survey. User experience interview responses were consistent in noting benefits of 'improved glycaemic control' and 'worrying less about diabetes'. CONCLUSION In this sample of older adults with T1D who have previously shown glycaemic benefit, there are indicators of improved PROs and subjective user experience benefits.
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Affiliation(s)
- A K Schneider-Utaka
- Division of Endocrinology and Diabetes, Stanford Diabetes Research Center, University, Stanford, California, USA
| | - S Hanes
- Division of Endocrinology and Diabetes, Stanford Diabetes Research Center, University, Stanford, California, USA
| | - C K Boughton
- Wellcome Trust-MRC Institute of Metabolic Science, University of Cambridge, Cambridge, UK
- Wolfson Diabetes and Endocrine Clinic, Cambridge University Hospitals NHS Foundation Trust, Cambridge, UK
| | - S Hartnell
- Wolfson Diabetes and Endocrine Clinic, Cambridge University Hospitals NHS Foundation Trust, Cambridge, UK
| | - H Thabit
- Diabetes, Endocrinology and Metabolism Centre, Manchester University NHS Foundation Trust, Manchester Academic Health Science Centre, Manchester, UK
- Division of Diabetes, Endocrinology and Gastroenterology, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK
| | - W M Mubita
- Diabetes, Endocrinology and Metabolism Centre, Manchester University NHS Foundation Trust, Manchester Academic Health Science Centre, Manchester, UK
| | - K Draxlbauer
- University Hospitals Birmingham NHS Foundation Trust, Birmingham, UK
| | - T Poettler
- Division of Endocrinology and Diabetology, Department of Internal Medicine, Medical University of Graz, Graz, Austria
| | - J Hayes
- Wellcome Trust-MRC Institute of Metabolic Science, University of Cambridge, Cambridge, UK
| | - M E Wilinska
- Wellcome Trust-MRC Institute of Metabolic Science, University of Cambridge, Cambridge, UK
| | - J K Mader
- Division of Endocrinology and Diabetology, Department of Internal Medicine, Medical University of Graz, Graz, Austria
| | - P Narendran
- University Hospitals Birmingham NHS Foundation Trust, Birmingham, UK
- Institute of Immunology and Immunotherapy, University of Birmingham, Birmingham, UK
| | - L Leelarathna
- Diabetes, Endocrinology and Metabolism Centre, Manchester University NHS Foundation Trust, Manchester Academic Health Science Centre, Manchester, UK
- Division of Diabetes, Endocrinology and Gastroenterology, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK
| | - M L Evans
- Wellcome Trust-MRC Institute of Metabolic Science, University of Cambridge, Cambridge, UK
- Wolfson Diabetes and Endocrine Clinic, Cambridge University Hospitals NHS Foundation Trust, Cambridge, UK
| | - R Hovorka
- Wellcome Trust-MRC Institute of Metabolic Science, University of Cambridge, Cambridge, UK
| | - K K Hood
- Division of Endocrinology and Diabetes, Stanford Diabetes Research Center, University, Stanford, California, USA
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Sathyanarayanan A, Crabtree T, Choudhary P, Elliott J, Evans ML, Lumb A, Wilmot EG. Delivering evidence-based interventions for type 1 diabetes in the virtual world - A review of UK practice during the SARS-CoV-2 pandemic. Diabetes Res Clin Pract 2022; 185:109777. [PMID: 35157943 PMCID: PMC8831709 DOI: 10.1016/j.diabres.2022.109777] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/06/2021] [Revised: 02/02/2022] [Accepted: 02/07/2022] [Indexed: 12/05/2022]
Abstract
AIMS This review considers the impact of the SARS-CoV-2 pandemic on access to interventions for those living with type 1 diabetes and discusses the solutions which have been considered and actioned to ensure ongoing access care. METHODS We performed a focussed review of the published literature, and the guidelines for changes that have been effected during the pandemic. We also drew from expert recommendations and information about local practice changes for areas where formal data have not been published. RESULTS Evidence based interventions which support the achievement of improved glucose levels and/or reduction in hypoglycaemia include group structured education to support self-management, insulin pump therapy and continuous glucose monitoring. The SARS-CoV-2 pandemic had impacted the ability of diabetes services to deliver these intervention. Multiple adaptations have been put in place - transition to online delivery of education and care, and usage of diabetes technology. CONCLUSIONS Although various adaptations have been made during the pandemic that have positively influenced uptake of services, there are many areas of delivery that need immediate improvement in the UK. We recommend a proactive approach in recognising the digital divide and inequity in distribution of these changes and we recommend introducing measures to reduce them.
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Affiliation(s)
| | - T Crabtree
- University Hospitals of Derby and Burton NHS FT, DE22 3NE, UK; Division of Medical Sciences & Graduate Entry Medicine, School of Medicine, University of Nottingham, NG7 2RD, UK.
| | - P Choudhary
- Diabetes Research Centre, Leicester Diabetes Centre - Bloom, University of Leicester, LE1 7RH, UK.
| | - J Elliott
- Department of Oncology and Metabolism, University of Sheffield, S10 2TN, UK.
| | - M L Evans
- Wellcome Trust/ MRC Institute of Metabolic Science and Department of Medicine, University of Cambridge, CB2 1TN, UK.
| | - A Lumb
- Oxford Centre for Diabetes, Endocrinology and Metabolism, Churchill Hospital, Oxford OX3 7LE, UK; NIHR Oxford Biomedical Research Centre, Oxford OX4 2PG, UK.
| | - E G Wilmot
- University Hospitals of Derby and Burton NHS FT, DE22 3NE, UK; Division of Medical Sciences & Graduate Entry Medicine, School of Medicine, University of Nottingham, NG7 2RD, UK
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Bally L, Thabit H, Ruan Y, Mader JK, Kojzar H, Dellweg S, Benesch C, Hartnell S, Leelarathna L, Wilinska ME, Evans ML, Arnolds S, Pieber TR, Hovorka R. Bolusing frequency and amount impacts glucose control during hybrid closed-loop. Diabet Med 2018; 35:347-351. [PMID: 28755444 PMCID: PMC5788742 DOI: 10.1111/dme.13436] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 07/25/2017] [Indexed: 12/16/2022]
Abstract
AIM To compare bolus insulin delivery patterns during closed-loop home studies in adults with suboptimally [HbA1c 58-86 mmol/mol (7.5%-10%)] and well-controlled [58 mmol/mol (< 7.5%)] Type 1 diabetes. METHODS Retrospective analysis of daytime and night-time insulin delivery during home use of closed-loop over 4 weeks. Daytime and night-time controller effort, defined as amount of insulin delivered by closed-loop relative to usual basal insulin delivery, and daytime bolus effort, defined as total bolus insulin delivery relative to total daytime insulin delivery were compared between both cohorts. Correlation analysis was performed between individual bolus behaviour (bolus effort and frequency) and daytime controller efforts, and proportion of time spent within and below sensor glucose target range. RESULTS Individuals with suboptimally controlled Type 1 diabetes had significantly lower bolus effort (P = 0.038) and daily bolus frequency (P < 0.001) compared with those with well-controlled diabetes. Controller effort during both daytime (P = 0.007) and night-time (P = 0.005) were significantly higher for those with suboptimally controlled Type 1 diabetes. Time when glucose was within the target range (3.9-10.0 mmol/L) during daytime correlated positively with bolus effort (r = 0.37, P = 0.016) and bolus frequency (r = 0.33, P = 0.037). Time when glucose was below the target range during daytime was comparable in both groups (P = 0.36), and did not correlate significantly with bolus effort (r = 0.28, P = 0.066) or bolus frequency (r = -0.21, P = 0.19). CONCLUSION More frequent bolusing and higher proportion of insulin delivered as bolus during hybrid closed-loop use correlated positively with time glucose was in target range. This emphasises the need for user input and educational support to benefit from this novel therapeutic modality.
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Affiliation(s)
- L. Bally
- Wellcome Trust–MRC Institute of Metabolic ScienceUniversity of CambridgeCambridgeUK
- Department of Diabetes & EndocrinologyCambridge University Hospitals NHS Foundation TrustCambridgeUK
- Department of Diabetes & EndocrinologyClinical Nutrition and Metabolism, InselspitalBern University HospitalUniversity of BernBernSwitzerland
| | - H. Thabit
- Wellcome Trust–MRC Institute of Metabolic ScienceUniversity of CambridgeCambridgeUK
- Department of Diabetes & EndocrinologyCambridge University Hospitals NHS Foundation TrustCambridgeUK
| | - Y. Ruan
- Wellcome Trust–MRC Institute of Metabolic ScienceUniversity of CambridgeCambridgeUK
- Department of PaediatricsUniversity of CambridgeCambridgeUK
| | - J. K. Mader
- Department of Internal MedicineDivision of Endocrinology & DiabetologyMedical University of GrazGrazAustria
| | - H. Kojzar
- Department of Internal MedicineDivision of Endocrinology & DiabetologyMedical University of GrazGrazAustria
| | - S. Dellweg
- Profil Institut fuer Stoffwechselforschung GmbHNeussGermany
| | - C. Benesch
- Profil Institut fuer Stoffwechselforschung GmbHNeussGermany
| | - S. Hartnell
- Department of Diabetes & EndocrinologyCambridge University Hospitals NHS Foundation TrustCambridgeUK
| | - L. Leelarathna
- Central Manchester University Hospitals NHS foundation Trust and University of ManchesterManchesterUK
| | - M. E. Wilinska
- Wellcome Trust–MRC Institute of Metabolic ScienceUniversity of CambridgeCambridgeUK
- Department of PaediatricsUniversity of CambridgeCambridgeUK
| | - M. L. Evans
- Wellcome Trust–MRC Institute of Metabolic ScienceUniversity of CambridgeCambridgeUK
- Department of Diabetes & EndocrinologyCambridge University Hospitals NHS Foundation TrustCambridgeUK
| | - S. Arnolds
- Profil Institut fuer Stoffwechselforschung GmbHNeussGermany
| | - T. R. Pieber
- Department of Internal MedicineDivision of Endocrinology & DiabetologyMedical University of GrazGrazAustria
| | - R. Hovorka
- Wellcome Trust–MRC Institute of Metabolic ScienceUniversity of CambridgeCambridgeUK
- Department of PaediatricsUniversity of CambridgeCambridgeUK
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4
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Thabit H, Tauschmann M, Allen JM, Leelarathna L, Hartnell S, Wilinska ME, Acerini CL, Dellweg S, Benesch C, Heinemann L, Mader JK, Holzer M, Kojzar H, Exall J, Yong J, Pichierri J, Barnard KD, Kollman C, Cheng P, Hindmarsh PC, Campbell FM, Arnolds S, Pieber TR, Evans ML, Dunger DB, Hovorka R. Home Use of an Artificial Beta Cell in Type 1 Diabetes. N Engl J Med 2015; 373:2129-2140. [PMID: 26379095 PMCID: PMC4697362 DOI: 10.1056/nejmoa1509351] [Citation(s) in RCA: 315] [Impact Index Per Article: 35.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
BACKGROUND The feasibility, safety, and efficacy of prolonged use of an artificial beta cell (closed-loop insulin-delivery system) in the home setting have not been established. METHODS In two multicenter, crossover, randomized, controlled studies conducted under free-living home conditions, we compared closed-loop insulin delivery with sensor-augmented pump therapy in 58 patients with type 1 diabetes. The closed-loop system was used day and night by 33 adults and overnight by 25 children and adolescents. Participants used the closed-loop system for a 12-week period and sensor-augmented pump therapy (control) for a similar period. The primary end point was the proportion of time that the glucose level was between 70 mg and 180 mg per deciliter for adults and between 70 mg and 145 mg per deciliter for children and adolescents. RESULTS Among adults, the proportion of time that the glucose level was in the target range was 11.0 percentage points (95% confidence interval [CI], 8.1 to 13.8) greater with the use of the closed-loop system day and night than with control therapy (P<0.001). The mean glucose level was lower during the closed-loop phase than during the control phase (difference, -11 mg per deciliter; 95% CI, -17 to -6; P<0.001), as were the area under the curve for the period when the glucose level was less than 63 mg per deciliter (39% lower; 95% CI, 24 to 51; P<0.001) and the mean glycated hemoglobin level (difference, -0.3%; 95% CI, -0.5 to -0.1; P=0.002). Among children and adolescents, the proportion of time with the nighttime glucose level in the target range was higher during the closed-loop phase than during the control phase (by 24.7 percentage points; 95% CI, 20.6 to 28.7; P<0.001), and the mean nighttime glucose level was lower (difference, -29 mg per deciliter; 95% CI, -39 to -20; P<0.001). The area under the curve for the period in which the day-and-night glucose levels were less than 63 mg per deciliter was lower by 42% (95% CI, 4 to 65; P=0.03). Three severe hypoglycemic episodes occurred during the closed-loop phase when the closed-loop system was not in use. CONCLUSIONS Among patients with type 1 diabetes, 12-week use of a closed-loop system, as compared with sensor-augmented pump therapy, improved glucose control, reduced hypoglycemia, and, in adults, resulted in a lower glycated hemoglobin level. (Funded by the JDRF and others; AP@home04 and APCam08 ClinicalTrials.gov numbers, NCT01961622 and NCT01778348.).
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Barnard KD, Wysocki T, Thabit H, Evans ML, Amiel S, Heller S, Young A, Hovorka R. Psychosocial aspects of closed- and open-loop insulin delivery: closing the loop in adults with Type 1 diabetes in the home setting. Diabet Med 2015; 32:601-8. [PMID: 25615888 DOI: 10.1111/dme.12706] [Citation(s) in RCA: 76] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 01/19/2015] [Indexed: 12/29/2022]
Abstract
AIMS To explore the psychosocial experiences of closed-loop technology and to compare ratings of closed- and open-loop technology for adults with Type 1 diabetes taking part in a randomized crossover study. METHODS Adults (aged > 18 years) on insulin pump therapy were recruited to receive a first phase of either real-time continuous glucose monitoring with overnight closed-loop or real-time continuous glucose monitoring alone (open-loop) followed by a second phase of the alternative treatment in random order, at home for 4 weeks, unsupervised. Participants were invited to share their views in semi-structured interviews. The impact of the closed-loop technology, positive and negative aspects of living with the device overnight, along with the hopes and anxieties of the participants, were explored. RESULTS The participants in the trial were 24 adults with a mean (sd) age of 43 (12) years, of whom 54% were men. The mean (range) interview duration was 26 (12-46) min. Content and thematic analysis showed the following key positive themes: improved blood glucose control (n = 16); reassurance/reduced worry (n = 16); improved overnight control leading to improved daily functioning and diabetes control (n = 16); and improved sleep (n = 8). The key negative themes were: technical difficulties (n = 24); intrusiveness of alarms (n = 13); and size of equipment (n = 7). Of the 24 participant, 20 would recommend the closed-loop technology. CONCLUSIONS Closed-loop therapy has positive effects when it works in freeing participants from the demands of self-management. The downside was technical difficulties, particularly concerning the pump and 'connectivity', which it is hoped will improve. Future research should continue to explore the acceptability of the closed-loop system as a realistic therapy option, taking account of user concerns as new systems are designed. Failure to do this may reduce the eventual utility of new systems.
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Affiliation(s)
- K D Barnard
- HDH, Faculty of Medicine, University of Southampton, Southampton, UK
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6
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Thabit H, Elleri D, Leelarathna L, Allen JM, Lubina-Solomon A, Stadler M, Walkinshaw E, Iqbal A, Choudhary P, Wilinska ME, Barnard KD, Heller SR, Amiel SA, Evans ML, Dunger DB, Hovorka R. Unsupervised home use of an overnight closed-loop system over 3-4 weeks: a pooled analysis of randomized controlled studies in adults and adolescents with type 1 diabetes. Diabetes Obes Metab 2015; 17:452-8. [PMID: 25492378 PMCID: PMC4510702 DOI: 10.1111/dom.12427] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/29/2014] [Revised: 12/01/2014] [Accepted: 12/04/2014] [Indexed: 12/25/2022]
Abstract
AIMS To compare overnight closed-loop and sensor-augmented pump therapy in patients with type 1 diabetes by combining data collected during free-living unsupervised randomized crossover home studies. METHODS A total of 40 participants with type 1 diabetes, of whom 24 were adults [mean ± standard deviation (s.d.) age 43 ± 12 years and glycated haemoglobin (HbA1c) 8.0 ± 0.9%] and 16 were adolescents (mean ± s.d. age 15.6 ± 3.6 years and HbA1c 8.1 ± 0.8%), underwent two periods of sensor-augmented pump therapy in the home setting, in combination with or without an overnight closed-loop insulin delivery system that uses a model predictive control algorithm to direct insulin delivery. The order of the two interventions was random; each period lasted 4 weeks in adults and 3 weeks in adolescents. The primary outcome was time during which sensor glucose readings were in the target range of 3.9-8.0 mmol/l. RESULTS The proportion of time when sensor glucose was in the target range (3.9-8.0 mmol/l) overnight (between 24:00 and 08:00 hours) was 18.5% greater during closed-loop insulin delivery than during sensor-augmented therapy (p < 0.001). Closed-loop therapy significantly reduced mean overnight glucose levels by 0.9 mmol/l (p < 0.001), with no difference in glycaemic variability, as measured by the standard deviation of sensor glucose. Time spent above the target range was reduced (p = 0.001), as was time spent in hypoglycaemia (<3.9 mmol/l; p = 0.014) during closed-loop therapy. Lower mean overnight glucose levels during closed-loop therapy were brought about by increased overnight insulin delivery (p < 0.001) without changes to the total daily delivery (p = 0.84). CONCLUSION Overnight closed-loop insulin therapy at home in adults and adolescents with type 1 diabetes is feasible, showing improvements in glucose control and reducing the risk of nocturnal hypoglycaemia.
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Affiliation(s)
- H Thabit
- Wellcome Trust-MRC Institute of Metabolic Science, University of Cambridge, Cambridge, UK
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7
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Ogunnowo-Bada EO, Heeley N, Brochard L, Evans ML. Brain glucose sensing, glucokinase and neural control of metabolism and islet function. Diabetes Obes Metab 2014; 16 Suppl 1:26-32. [PMID: 25200293 PMCID: PMC4405079 DOI: 10.1111/dom.12334] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/29/2014] [Accepted: 06/05/2014] [Indexed: 11/30/2022]
Abstract
It is increasingly apparent that the brain plays a central role in metabolic homeostasis, including the maintenance of blood glucose. This is achieved by various efferent pathways from the brain to periphery, which help control hepatic glucose flux and perhaps insulin-stimulated insulin secretion. Also, critically important for the brain given its dependence on a constant supply of glucose as a fuel--emergency counter-regulatory responses are triggered by the brain if blood glucose starts to fall. To exert these control functions, the brain needs to detect rapidly and accurately changes in blood glucose. In this review, we summarize some of the mechanisms postulated to play a role in this and examine the potential role of the low-affinity hexokinase, glucokinase, in the brain as a key part of some of this sensing. We also discuss how these processes may become altered in diabetes and related metabolic diseases.
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Affiliation(s)
- E O Ogunnowo-Bada
- Wellcome Trust-MRC Institute of Metabolic Science, IMS Metabolic Research Laboratories, University of CambridgeCambridge, UK
| | - N Heeley
- Wellcome Trust-MRC Institute of Metabolic Science, IMS Metabolic Research Laboratories, University of CambridgeCambridge, UK
| | - L Brochard
- Wellcome Trust-MRC Institute of Metabolic Science, IMS Metabolic Research Laboratories, University of CambridgeCambridge, UK
| | - M L Evans
- Wellcome Trust-MRC Institute of Metabolic Science, IMS Metabolic Research Laboratories, University of CambridgeCambridge, UK
- Correspondence to: Mark Evans, Wellcome Trust-MRC Institute of Metabolic Science, University of Cambridge, IMS Metabolic Research Laboratories, Box 289 Addenbrookes Hospital, Hills Road, Cambridge CB2 0QQ, UK. E-mail:
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Thabit H, Kumareswaran K, Haidar A, Leelarathna L, Caldwell K, Elleri D, Allen JM, Nodale M, Wilinska ME, Jackson NC, Umpleby AM, Evans ML, Hovorka R. Glucose turnover after replacement of usual therapy by insulin in insulin-naive type 2 diabetes subjects. J Clin Endocrinol Metab 2014; 99:2225-32. [PMID: 24606105 DOI: 10.1210/jc.2013-4519] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
CONTEXT Discontinuation of anti-hyperglycemic oral agents and initiation of insulin is recommended in certain clinical situations for inpatients with type 2 diabetes (T2D). The effects on glucose turnover when these agents are acutely withdrawn are poorly understood and may be of importance when insulin therapy is initiated. OBJECTIVE Our objective was to investigate alterations in glucose turnover after acute withdrawal of noninsulin therapy. DESIGN AND SETTING This was a randomized crossover study at a clinical research facility. PARTICIPANTS Participants included 12 insulin-naive subjects with T2D. METHODS Subjects attended two 24-hour visits. Standard therapy was discontinued and replaced by closed-loop insulin delivery during the intervention visit. Usual anti-hyperglycemic therapy was continued during the control visit. Systemic glucose appearance (Ra) and glucose disposal (Rd) were measured using a tracer dilution technique with iv [6,6-(2)H2]glucose. RESULTS Plasma glucose profiles during both visits were comparable (P = .48). Glucose Ra increased during the day (21.4 [19.5, 23.5] vs 18.6 [17.0, 21.6) μmol/kg/min, P = .019) and decreased overnight (9.7 [8.5, 11.4] vs 11.6 [10.3, 12.9] μmol/kg/min, P = .004) when the usual therapy was discontinued and replaced with insulin. Increased daytime glucose Rd (21.2 [19.4, 23.9] vs 18.8 [18.3, 21.7] μmol/kg/min, P = .002) and decreased overnight Rd (10.4 [9.1, 12.0] vs 11.8 [10.7, 13.7] μmol/kg/min, P = .005) were observed when the usual therapy was discontinued, whereas daytime peripheral insulin sensitivity was reduced (47.8 [24.8, 66.1] vs 62.5 [34.8, 75.8] nmol/kg/min per pmol/L, P = .034). CONCLUSION In T2D, acute discontinuation of anti-hyperglycemic therapy and replacement with insulin increases postprandial Ra and reduces peripheral insulin sensitivity. Insulin dose initiation may need to compensate for these alterations.
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Affiliation(s)
- H Thabit
- Metabolic Research Laboratories (H.T., K.K., L.L., K.C., D.E., J.M.A., M.N., M.E.W., M.L.E., R.H.), Wellcome Trust-Medical Research Council Institute of Metabolic Science, and Department of Paediatrics (D.E., J.M.A., M.E.W., R.H.), University of Cambridge, Cambridge CB2 0QQ, United Kingdom; Centre for Intelligent Machines (A.H.), McGill University, Montreal, Quebec H3A 0E9, Canada; and Postgraduate Medical School (N.C.J., A.M.U.), University of Surrey, Guildford GU2 7TE, United Kingdom
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Hollaway GJ, Evans ML, Wallwork H, Dyson CB, McKay AC. Yield Loss in Cereals, Caused by Fusarium culmorum and F. pseudograminearum, Is Related to Fungal DNA in Soil Prior to Planting, Rainfall, and Cereal Type. Plant Dis 2013; 97:977-982. [PMID: 30722534 DOI: 10.1094/pdis-09-12-0867-re] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
In southeastern Australia, Fusarium crown rot, caused by Fusarium culmorum or F. pseudograminearum, is an increasingly important disease of cereals. Because in-crop control options are limited, it is important for growers to know prior to planting which fields are at risk of yield loss from crown rot. Understanding the relationships between crown rot inoculum and yield loss would assist in assessing the risk of yield loss from crown rot in fields prior to planting. Thirty-five data sets from crown rot management experiments conducted in the states of South Australia and Victoria during the years 2005 to 2010 were examined. Relationships between Fusarium spp. DNA concentrations (inoculum) in soil samples taken prior to planting and disease development and grain yield were evaluated in seasons with contrasting seasonal rainfall. F. culmorum and F. pseudograminearum DNA concentrations in soil prior to planting were found to be positively related to crown rot expression (stem browning and whiteheads) and negatively related to grain yield of durum wheat, bread wheat, and barley. Losses from crown rot were greatest when rainfall during September and October (crop maturation) was below the long-term average. Losses from crown rot were greater in durum wheat than bread wheat and least in barley. Yield losses from F. pseudograminearum were similar to yield losses from F. culmorum. Yield loss patterns were consistent across experiments and between states; therefore, it is reasonable to expect that similar relationships will occur over broad geographic areas. This suggests that quantitative polymerase chain reaction technology and soil sampling could be powerful tools for assessing crown rot inoculum concentrations prior to planting and predicting the risk of yield loss from crown rot wherever this disease is an issue.
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Affiliation(s)
- G J Hollaway
- Biosciences Research Division, Department of Environment & Primary Industries, Horsham, 3401, Victoria, Australia
| | - M L Evans
- South Australian Research and Development Institute, Adelaide, 5001, South Australia, Australia
| | - H Wallwork
- South Australian Research and Development Institute, Adelaide, 5001, South Australia, Australia
| | - C B Dyson
- South Australian Research and Development Institute, Adelaide, 5001, South Australia, Australia
| | - A C McKay
- South Australian Research and Development Institute, Adelaide, 5001, South Australia, Australia
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Elleri D, Allen JM, Harris J, Kumareswaran K, Nodale M, Leelarathna L, Acerini CL, Haidar A, Wilinska ME, Jackson N, Umpleby AM, Evans ML, Dunger DB, Hovorka R. Absorption patterns of meals containing complex carbohydrates in type 1 diabetes. Diabetologia 2013; 56:1108-17. [PMID: 23435829 DOI: 10.1007/s00125-013-2852-x] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/28/2012] [Accepted: 01/21/2013] [Indexed: 02/07/2023]
Abstract
AIMS/HYPOTHESIS Successful postprandial glycaemia management requires understanding of absorption patterns after meals containing variable complex carbohydrates. We studied eight young participants with type 1 diabetes to investigate a large low-glycaemic-load (LG) meal and another eight participants to investigate a high-glycaemic-load (HG) meal matched for carbohydrates (121 g). METHODS On Visit 1, participants consumed an evening meal. On follow-up Visit 2, a variable-target glucose clamp was performed to reproduce glucose and insulin levels from Visit 1. Adopting stable-label tracer dilution methodology, we measured endogenous glucose production on Visit 2 and subtracted it from total glucose appearance measured on Visit 1 to obtain meal-attributable glucose appearance. RESULTS After the LG meal, 25%, 50% and 75% of cumulative glucose appearance was at 88 ± 21, 175 ± 39 and 270 ± 54 min (mean ± SD), whereas glucose from the HG meal appeared significantly faster at 56 ± 12, 100 ± 25 and 153 ± 39 min (p < 0.001 to 0.003), and resulted in a 50% higher peak appearance (p < 0.001). Higher apparent bioavailability by 15% (p = 0.037) was observed after the LG meal. We documented a 20 min deceleration of dietary mixed carbohydrates compared with dietary glucose for the HG meal and a twofold deceleration for the LG meal. CONCLUSIONS/INTERPRETATION Absorption patterns may be influenced by glycaemic load and/or meal composition, affecting optimum prandial insulin dosing in type 1 diabetes.
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Affiliation(s)
- D Elleri
- University of Cambridge Metabolic Research Laboratories and NIHR Cambridge Biomedical Research Centre, Institute of Metabolic Science, Box 289, Addenbrooke's Hospital, Hills Road, Cambridge CB2 0QQ, UK
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11
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Moss CE, Marsh WJ, Parker HE, Ogunnowo-Bada E, Riches CH, Habib AM, Evans ML, Gribble FM, Reimann F. Somatostatin receptor 5 and cannabinoid receptor 1 activation inhibit secretion of glucose-dependent insulinotropic polypeptide from intestinal K cells in rodents. Diabetologia 2012; 55:3094-103. [PMID: 22872212 PMCID: PMC3464380 DOI: 10.1007/s00125-012-2663-5] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/26/2012] [Accepted: 07/03/2012] [Indexed: 12/25/2022]
Abstract
AIMS/HYPOTHESIS Glucose-dependent insulinotropic polypeptide (GIP) is an enteroendocrine hormone that promotes storage of glucose and fat. Its secretion from intestinal K cells is triggered by nutrient ingestion and is modulated by intracellular cAMP. In view of the proadipogenic actions of GIP, this study aimed to identify pathways in K cells that lower cAMP levels and GIP secretion. METHODS Murine K cells purified by flow cytometry were analysed for expression of G(αi)-coupled receptors by transcriptomic microarrays. Somatostatin and cannabinoid receptor expression was confirmed by quantitative RT-PCR. Hormone secretion in vitro was measured in GLUTag and primary murine intestinal cultures. cAMP was monitored in GLUTag cells using the genetically encoded sensor Epac2-camps. In vivo tolerance tests were performed in cannulated rats. RESULTS Purified murine K cells expressed high mRNA levels for somatostatin receptors (Sstrs) Sstr2, Sstr3 and Sstr5, and cannabinoid receptor type 1 (Cnr1, CB1). Somatostatin inhibited GIP and glucagon-like peptide-1 (GLP-1) secretion from primary small intestinal cultures, in part through SSTR5, and reduced cAMP generation in GLUTag cells. Although the CB1 agonist methanandamide (mAEA) inhibited GIP secretion, no significant effect was observed on GLP-1 secretion from primary cultures. In cannulated rats, treatment with mAEA prior to an oral glucose tolerance test suppressed plasma GIP but not GLP-1 levels, whereas the CB1 antagonist AM251 elevated basal GIP concentrations. CONCLUSIONS/INTERPRETATION GIP release is inhibited by somatostatin and CB1 agonists. The differential effects of CB1 ligands on GIP and GLP-1 release may provide a new tool to dissociate secretion of these incretin hormones and lower GIP but not GLP-1 levels in vivo.
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MESH Headings
- Animals
- Colon/cytology
- Colon/metabolism
- Cyclic AMP/metabolism
- Enteroendocrine Cells/cytology
- Enteroendocrine Cells/metabolism
- Gastric Inhibitory Polypeptide/metabolism
- Glucagon-Like Peptide 1/metabolism
- Incretins/metabolism
- Intestine, Small/cytology
- Intestine, Small/metabolism
- Male
- Mice
- Mice, Inbred C57BL
- Primary Cell Culture
- RNA, Messenger/metabolism
- Rats
- Rats, Sprague-Dawley
- Receptor, Cannabinoid, CB1/genetics
- Receptor, Cannabinoid, CB1/metabolism
- Receptors, Somatostatin/genetics
- Receptors, Somatostatin/metabolism
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Affiliation(s)
- C. E. Moss
- Cambridge Institute for Medical Research, Wellcome Trust/MRC Building, Addenbrooke’s Hospital, Box 139, Hills Road, Cambridge, CB2 0XY UK
| | - W. J. Marsh
- Cambridge Metabolic Research Laboratories and Department of Medicine, Addenbrooke’s Hospital, Hills Road, Cambridge, UK
| | - H. E. Parker
- Cambridge Institute for Medical Research, Wellcome Trust/MRC Building, Addenbrooke’s Hospital, Box 139, Hills Road, Cambridge, CB2 0XY UK
| | - E. Ogunnowo-Bada
- Cambridge Metabolic Research Laboratories and Department of Medicine, Addenbrooke’s Hospital, Hills Road, Cambridge, UK
| | - C. H. Riches
- Cambridge Metabolic Research Laboratories and Department of Medicine, Addenbrooke’s Hospital, Hills Road, Cambridge, UK
| | - A. M. Habib
- Cambridge Institute for Medical Research, Wellcome Trust/MRC Building, Addenbrooke’s Hospital, Box 139, Hills Road, Cambridge, CB2 0XY UK
| | - M. L. Evans
- Cambridge Metabolic Research Laboratories and Department of Medicine, Addenbrooke’s Hospital, Hills Road, Cambridge, UK
| | - F. M. Gribble
- Cambridge Institute for Medical Research, Wellcome Trust/MRC Building, Addenbrooke’s Hospital, Box 139, Hills Road, Cambridge, CB2 0XY UK
| | - F. Reimann
- Cambridge Institute for Medical Research, Wellcome Trust/MRC Building, Addenbrooke’s Hospital, Box 139, Hills Road, Cambridge, CB2 0XY UK
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12
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Evans ML, Bernatchez L. Oxidative phosphorylation gene transcription in whitefish species pairs reveals patterns of parallel and nonparallel physiological divergence. J Evol Biol 2012; 25:1823-34. [PMID: 22830417 DOI: 10.1111/j.1420-9101.2012.02570.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2012] [Accepted: 05/31/2012] [Indexed: 12/31/2022]
Abstract
Across multiple lakes in North America, lake whitefish (Coregonus clupeaformis) have independently evolved 'dwarf' and 'normal' sympatric species pairs that exhibit pronounced phenotypic and genetic divergence. In particular, traits associated with metabolism have been shown to be highly differentiated between whitefish species. Here, we examine the transcription of genes associated with the five mitochondrial and nuclear genome-encoded oxidative phosphorylation (OXPHOS) complexes, the primary physiological mechanism responsible for the production of ATP, in whitefish species pairs from Cliff Lake and Webster Lake in Maine, USA. We observed OXPHOS gene transcription divergence between dwarf and normal whitefish in each of the two lakes, with the former exhibiting transcription upregulation for genes associated with each of the OXPHOS complexes. We also observed a significant influence of lake on transcription levels for some of the genes, indicating that inter-lake ecological or genetic differences are contributing to variation in OXPHOS gene transcription levels. Together, our results support the hypothesis that metabolic divergence is a critical adaptation involved in whitefish speciation and implicate OXPHOS gene upregulation as a factor involved in meeting the enhanced energetic demands of dwarf whitefish. Further studies are now needed to evaluate the contribution of genetically vs. plasticity driven variation in transcription associated with this critical physiological pathway.
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Affiliation(s)
- M L Evans
- Institut de Biologie Intégrative et des Systèmes, Pavillon Charles-Eugène-Marchand, Université Laval, Québec, QC, Canada.
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13
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Haidar A, Elleri D, Allen JM, Harris J, Kumareswaran K, Nodale M, Acerini CL, Wilinska ME, Jackson N, Umpleby AM, Evans ML, Dunger DB, Hovorka R. Validity of triple- and dual-tracer techniques to estimate glucose appearance. Am J Physiol Endocrinol Metab 2012; 302:E1493-501. [PMID: 22454288 PMCID: PMC3378162 DOI: 10.1152/ajpendo.00581.2011] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/23/2011] [Accepted: 03/21/2012] [Indexed: 11/22/2022]
Abstract
The triple-tracer (TT) dilution technique has been proposed to be the gold standard method to measure postprandial glucose appearance. However, validation against an independent standard has been missing. We addressed this issue and also validated the simpler dual-tracer (DT) technique. Sixteen young subjects with type 1 diabetes (age 19.5 ± 3.8 yr, BMI 23.4 ± 1.5 kg/m(2), HbA(1c) 8.7 ± 1.7%, diabetes duration 9.0 ± 6.9 yr, total daily insulin 0.9 ± 0.2 U·kg(-1)·day(-1), mean ± SD) received a variable intravenous 20% dextrose infusion enriched with [U-(13)C]glucose over 8 h to achieve postprandial-resembling glucose excursions while intravenous insulin was administered to achieve postprandial-resembling levels of plasma insulin. Primed [6,6-(2)H(2)]glucose was infused in a manner that mimicked the expected endogenous glucose production and [U-(13)C; 1,2,3,4,5,6,6-(2)H(7)]glucose was infused in a manner that mimicked the expected glucose appearance from a standard meal. Plasma glucose enrichment was measured by gas chromatography-mass spectrometry. The intravenous dextrose infusion served as an independent standard and was reconstructed using the TT and DT techniques with the two-compartment Radziuk/Mari model and an advanced stochastic computational method. The difference between the infused and reconstructed dextrose profile was similar for the two methods (root mean square error 6.6 ± 1.9 vs. 8.0 ± 3.5 μmol·kg(-1)·min(-1), TT vs. DT, P = NS, paired t-test). The TT technique was more accurate in recovering the overall dextrose infusion (100 ± 9 and 92 ± 12%; P = 0.02). The root mean square error associated with the mean dextrose infusion profile was 2.5 and 3.3 μmol·kg(-1)·min(-1) for the TT and DT techniques, respectively. We conclude that the TT and DT techniques combined with the advanced computational method can measure accurately exogenous glucose appearance. The TT technique tends to outperform slightly the DT technique, but the latter benefits from reduced experimental and computational complexity.
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Affiliation(s)
- A. Haidar
- Metabolic Research Laboratories, Institute of Metabolic Science, University of Cambridge, Cambridge, United Kingdom
- Centre for Intelligent Machines, McGill University, Montreal, Quebec, Canada
| | - D. Elleri
- Metabolic Research Laboratories, Institute of Metabolic Science, University of Cambridge, Cambridge, United Kingdom
- Department of Paediatrics, University of Cambridge, Cambridge, United Kingdom; and
| | - J. M. Allen
- Metabolic Research Laboratories, Institute of Metabolic Science, University of Cambridge, Cambridge, United Kingdom
- Department of Paediatrics, University of Cambridge, Cambridge, United Kingdom; and
| | - J. Harris
- Metabolic Research Laboratories, Institute of Metabolic Science, University of Cambridge, Cambridge, United Kingdom
| | - K. Kumareswaran
- Metabolic Research Laboratories, Institute of Metabolic Science, University of Cambridge, Cambridge, United Kingdom
| | - M. Nodale
- Metabolic Research Laboratories, Institute of Metabolic Science, University of Cambridge, Cambridge, United Kingdom
| | - C. L. Acerini
- Department of Paediatrics, University of Cambridge, Cambridge, United Kingdom; and
| | - M. E. Wilinska
- Metabolic Research Laboratories, Institute of Metabolic Science, University of Cambridge, Cambridge, United Kingdom
| | - N. Jackson
- Postgraduate Medical School, University of Surrey, Guilford, United Kingdom
| | - A. M. Umpleby
- Postgraduate Medical School, University of Surrey, Guilford, United Kingdom
| | - M. L. Evans
- Metabolic Research Laboratories, Institute of Metabolic Science, University of Cambridge, Cambridge, United Kingdom
| | - D. B. Dunger
- Metabolic Research Laboratories, Institute of Metabolic Science, University of Cambridge, Cambridge, United Kingdom
- Department of Paediatrics, University of Cambridge, Cambridge, United Kingdom; and
| | - R. Hovorka
- Metabolic Research Laboratories, Institute of Metabolic Science, University of Cambridge, Cambridge, United Kingdom
- Department of Paediatrics, University of Cambridge, Cambridge, United Kingdom; and
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14
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Abstract
The application of calcium chelating agents (EDTA or EGTA) to the tips of maize roots caused a loss of gravitropic sensitivity. When the chelator was replaced with calcium chloride, gravitropic sensitivity was restored. Asymmetric application of calcium chloride near the tip of a vertical root caused curvature toward the calcium source. When the calcium was applied to the upper surface of the tip of a root oriented horizontally, the root curved upward even though control roots exhibited strong downward curvature. Application of calcium chloride to the tips of decapped roots, which are known to be gravitropically insensitive, did not restore gravitropic sensitivity. However, asymmetric application of calcium chloride near the tips of decapped roots caused curvature toward the calcium source. Calcium may play a key role in linking gravity detection to gravitropic curvature in roots.
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15
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Abstract
When the esterase substrate alpha-naphthyl acetate is added to segments from coleoptiles of oat (Avena sativa L., var. Victory) or corn (Zea mays L., Bear hybrid WF 9 x 38) or to roots of lentil (Lens culinaris Med.), it is rapidly taken up and hydrolyzed to alpha-naphthol and acetic acid. This technique was used to generate intracellular acid and to study the effect of its efflux on growth. With corn coleoptile segments, treatment with alpha-naphthyl acetate induced more rapid and more prolonged growth than did exposure to external acidic buffers. Dose-response studies of alpha-naphthyl acetate induction of H(+) secretion and growth indicated the existence of a distinct threshold rate of H(+) efflux below which growth is not enhanced. The rate of H(+) efflux induced by optimal levels of auxin appears to be at or below this threshold level in corn coleoptile tissue. These data indicate that the relationship between external acidification and elongation is not a simple one and that the effectiveness of H(+) entering the cell wall may depend on factors not directly correlated with the appearance of H(+) in the external medium.
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Affiliation(s)
- M J Vesper
- Department of Botany, The Ohio State University, Columbus, Ohio 43210
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16
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Evans ML, Neff BD, Heath DD. MHC genetic structure and divergence across populations of Chinook salmon (Oncorhynchus tshawytscha). Heredity (Edinb) 2009; 104:449-59. [PMID: 19773808 DOI: 10.1038/hdy.2009.121] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
The major histocompatibility complex (MHC) is thought to be under strong selection pressure because of its integral role in pathogen recognition. Consequently, patterns of MHC genetic variation should reflect selection pressures across the landscape. We examined genetic variation and population genetic structure at the MHC class I-A1 and class II-B1 exons in five Chinook salmon (Oncorhynchus tshawytscha) populations from two geographic regions in British Columbia, Canada. We then compared estimates of population structure at the MHC genes with neutral estimates based on microsatellites to examine the potential for local adaptation at the MHC. Chinook salmon are in decline throughout much of their native range and understanding the degree of local adaptation exhibited by the MHC may be important in conservation planning. Comparisons among populations yielded higher G'(ST) estimates for the MHC class I than expected under neutrality based on the microsatellites. In contrast, the MHC class II tended to exhibit lower G'(ST) values than did the microsatellites. These results suggest that across populations unique selection pressures are driving allele frequency differences at the MHC class I but that the MHC class II may be the subject of homogenizing selection. Rates of nonsynonymous versus synonymous substitutions found in codons associated within the MHC class I and II peptide-binding regions provided strong evidence of positive selection. Together, these results support the hypothesis that selection is influencing genetic variation at the MHC, but suggest that selection pressures may vary at the two classes of loci both at the sequence and population levels.
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Affiliation(s)
- M L Evans
- Department of Biology, University of Western Ontario, Ontario, Canada
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17
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Abstract
AIM To investigate the potential for the non-glucose metabolic substrate alanine to support brain function during glucose deprivation in man. METHODS Seven healthy men were studied on two occasions using a hyperinsulinaemic glucose clamp to lower arterialized plasma glucose to 2.5 mmol/l, in the presence of either 2 mmol/kg/h alanine infusion or saline, measuring counter-regulatory hormonal responses, symptoms generated and cognitive function with a mini-battery of tests sensitive to hypoglycaemia. RESULTS Alanine infusion elevated plasma alanine (peak value 1481 +/- 1260 vs. 138 +/- 32 micro mol/l, P = 0.02 alanine vs. saline) and lactate (peak value 3.09 +/- 0.14 vs. 2.05 +/- 0.12 mmol/l, P = 0.02). Cognitive function assessed by the Stroop word and colour subtests deteriorated less with alanine than saline (P < 0.01 for both). Other cognitive function tests deteriorated equally and counter-regulatory hormones rose equally during hypoglycaemia in both studies (P > 0.34) except for increased glucagon with alanine (peak 260 +/- 53 vs. 91 + 8 ng/l, P = 0.03). There was no significant effect of alanine on either autonomic or neuroglycopenic symptom scores. CONCLUSIONS Some, but not all, aspects of cognitive performance may be supported by an alanine infusion during hypoglycaemia. It is not clear whether alanine supports brain function directly or via increased availability of lactate. These data contribute to the growing evidence that regional metabolic differences exist in the brain's ability to use non-glucose fuels during hypoglycaemia.
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Affiliation(s)
- M L Evans
- Department of Medicine, University of Cambridge, Box 157 Addenbrooke's Hospital, Hills Road, Cambridge CB2 2QQ, UK
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18
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Abstract
Visceral pain is the most common form of pain produced by disease and is thus of interest in the study of gastrointestinal (GI) complaints such as irritable bowel syndrome, in which sensory signals perceived as GI pain travel in extrinsic afferent neurones with cell bodies in the dorsal root ganglia (DRG). The DRG from which the primary spinal afferent innervation of the mouse descending colon arises are not well defined. This study has combined retrograde labelling and immunohistochemistry to identify and characterize these neurones. Small to medium-sized retrogradely labelled cell bodies were found in the DRG at levels T8-L1 and L6-S1. Calcitonin gene-related peptide (CGRP)- and P2X3-like immunoreactivity (LI) was seen in 81 and 32%, respectively, of retrogradely labelled cells, and 20% bound the Griffonia simplicifolia-derived isolectin IB4. CGRP-LI and IB4 were co-localized in 22% of retrogradely labelled cells, whilst P2X3-LI and IB4 were co-localized in 7% (vs 34% seen in the whole DRG population). Eighty-two per cent of retrogradely labelled cells exhibited vanilloid receptor 1-like immunoreactivity (VR1-LI). These data suggest that mouse colonic spinal primary afferent neurones are mostly peptidergic CGRP-containing, VR1-LI, C fibre afferents. In contrast to the general DRG population, a subset of neurones exist that are P2X3 receptor-LI but do not bind IB4.
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Affiliation(s)
- D R Robinson
- Department of Pharmacology, University of Cambridge, Cambridge, UK
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19
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Jacob RJ, Fan X, Evans ML, Dziura J, Sherwin RS. Brain glucose levels are elevated in chronically hyperglycemic diabetic rats: no evidence for protective adaptation by the blood brain barrier. Metabolism 2002; 51:1522-4. [PMID: 12489061 DOI: 10.1053/meta.2002.36347] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Recent evidence suggests that brain function may be impaired by prolonged elevations of blood glucose, such as those that occur in poorly controlled diabetes. However, little is known about the effects of such hyperglycemia on brain metabolic substrate levels. Using microdialysis in awake, freely moving rats, we directly measured brain extracellular fluid (ECF) glucose, lactate, and beta-hydroxybutyrate (betaOHB) levels in the inferior colliculus in chronically hyperglycemic BB/wor diabetic rats and in control (Sprague-Dawley) rats during euglycemia and acute hyperglycemia. The ECF:plasma glucose ratio (0.27 to 0.34) was remarkably similar in animals from all 3 groups, resulting in proportional elevations of brain ECF glucose in the hyperglycemic groups. Moreover, brain ECF levels of lactate and beta-OHB were increased in diabetic (DM) rats as compared with controls. Our results suggest that no significant protective adaptation of the blood brain barrier (BBB) transfer of glucose occurs in chronic hyperglycemia. Hence, brain tissue may be chronically exposed to markedly elevated levels of glucose and other metabolic fuels during poorly controlled diabetes, and therefore it may be subject to the same long-term adverse effects of hyperglycemia seen in peripheral tissues.
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Affiliation(s)
- R J Jacob
- Department of Medicine, Yale University School of Medicine, New Haven, CT, USA
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20
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McCrimmon RJ, Evans ML, Jacob RJ, Fan X, Zhu Y, Shulman GI, Sherwin RS. AICAR and phlorizin reverse the hypoglycemia-specific defect in glucagon secretion in the diabetic BB rat. Am J Physiol Endocrinol Metab 2002; 283:E1076-83. [PMID: 12376337 DOI: 10.1152/ajpendo.00195.2002] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Individuals with type 1 diabetes demonstrate a hypoglycemia-specific defect in glucagon secretion. To determine whether intraislet hyperinsulinemia plays a role in the genesis of this defect, glucagon-secretory responses to moderate hypoglycemia induced by either insulin or a novel combination of the noninsulin glucose-lowering agents 5-aminoimidazole-4-carboxamide (AICAR) and phlorizin were compared in diabetic BB rats (an animal model of type 1 diabetes) and nondiabetic BB rats. The phlorizin-AICAR combination was able to induce moderate and equivalent hypoglycemia in both diabetic and nondiabetic BB rats in the absence of marked hyperinsulinemia. Diabetic BB rats demonstrated impaired glucagon and epinephrine responses during insulin-induced hypoglycemia compared with nondiabetic rats. In contrast, both glucagon (9- to 10-fold increase) and epinephrine (5- to 6-fold increase) responses were markedly improved during phlorizin-AICAR hypoglycemia. Combining phlorizin, AICAR, and insulin attenuated the glucagon response to hypoglycemia by 70% in the diabetic BB rat. Phlorizin plus AICAR had no effect on counterregulatory hormones under euglycemic conditions. We conclude that alpha-cell glucagon secretion in response to hypoglycemia is not defective if intraislet hyperinsulinemia is prevented. This suggests that exogenous insulin plays a pivotal role in the etiology of this defect.
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Affiliation(s)
- R J McCrimmon
- Department of Internal Medicine and Endocrinology, Yale University School of Medicine, New Haven, Connecticut 06520, USA
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21
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Evans ML, Sherwin RS. Brain glucose metabolism and hypoglycaemia. Diabetes Nutr Metab 2002; 15:294-6; discussion 296. [PMID: 12625472] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 03/01/2023]
Affiliation(s)
- M L Evans
- Diabetes Endocrine Research Center, Department of Internal Medicine, Yale School of Medicine, New Haven 06520, USA
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22
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Mullen JL, Wolverton C, Ishikawa H, Hangarter RP, Evans ML. Spatial separation of light perception and growth response in maize root phototropism. Plant Cell Environ 2002; 25:1191-1196. [PMID: 12361060 DOI: 10.1046/j.1365-3040.2002.00899.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Although the effects of gravity on root growth are well known and interactions between light and gravity have been reported, details of root phototropic responses are less documented. We used high-resolution image analysis to study phototropism in primary roots of Zea mays L. Similar to the location of perception in gravitropism, the perception of light was localized in the root cap. Phototropic curvature away from the light, on the other hand, developed in the central elongation zone, more basal than the site of initiation of gravitropic curvature. The phototropic curvature saturated at approximately 10 micromoles m-2 s-1 blue light with a peak curvature of 29 +/- 4 degrees, in part due to induction of positive gravitropism following displacement of the root tip from vertical during negative phototropism. However, at higher fluence rates, development of phototropic curvature is arrested even if gravitropism is avoided by maintaining the root cap vertically using a rotating feedback system. Thus continuous illumination can cause adaptation in the signalling pathway of the phototropic response in roots.
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Affiliation(s)
- J L Mullen
- Department of Biology, Indiana University, Bloomington, IN 47405, USA.
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23
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Abstract
A combination of microspectrofluorimetry and single cell voltage-clamp was used to examine the response to ATP of cultured neurons from rat dorsal root ganglia. ATP activated an inward current and a rise in internal calcium concentration that was dependent on the external calcium concentration and on the magnitude of the ATP-induced current response. The response was not affected by prerelease of internal calcium stores with caffeine. The rise in internal calcium was increased at hyperpolarized membrane potentials as the calcium driving force was increased. These results demonstrate that the ATP-gated channels in these cells can admit a significant amount of calcium in a physiological calcium gradient. This alternative calcium entry pathway could provide an internal calcium signal that is spatially distinct to that generated by voltage-gated calcium entry.
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Affiliation(s)
- M. M. Bouvier
- Department of Pharmacology, Smith Kline & French Research, The Frythe, Welwyn Garden City, AL6 9AR, UK
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24
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Abegg AL, Vickery LE, Bremer ME, Donnelly AM, Doshi PD, Evans ML, Thurman TL, Braford SR, Caparon MH, Bauer SC, Giri JG, Welply JK, McKearn JP, Smith WG. The enhanced in vitro hematopoietic activity of leridistim, a chimeric dual G-CSF and IL-3 receptor agonist. Leukemia 2002; 16:316-26. [PMID: 11896534 DOI: 10.1038/sj.leu.2402366] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2001] [Accepted: 10/18/2001] [Indexed: 11/08/2022]
Abstract
The in vitro activity of leridistim was characterized for cell proliferation, generation of colony-forming units (CFU) and differentiation of CD34+ cells. In AML-193.1.3 cells, leridistim exhibited a significant increase in potency compared to rhG-CSF, SC-65303 (an IL-3 receptor agonist) or an equimolar combination of rhG-CSF and SC-65303. CFU-GM assays demonstrated that at 50% of the maximum response, the relative potency of leridistim was 12-fold greater than the combination of rhG-CSF and rhIL-3 and 44-fold more potent than rhG-CSF alone. In multi-lineage CFU assays, a combination of erythropoietin (rhEPO) and leridistim resulted in greater numbers of BFU-E, CFU-GEMM and CFU-Mk than rhEPO alone. Ex vivo culture of peripheral blood or bone marrow CD34+ cells with leridistim substantially increased total viable cells over cultures stimulated with rhG-CSF, SC-65303, or a combination of rhG-CSF and SC-65303. Culture with leridistim, resulted in a greater increase in myeloid (CD15+/CD11b+), monocytic (CD41-/CD14+) and megakaryocytic (CD41+/CD14-) precursor cells without depleting the progenitor pool (CD34+/CD15-/CD11b-). These results demonstrate that leridistim is a more potent stimulator of hematopoietic proliferation and differentiation than the single receptor agonists (rhG-CSF and SC-65303) either alone or combined. These unique attributes suggest that leridistim may enhance hematopoietic reconstitution following myelosuppressive chemotherapy.
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Affiliation(s)
- A L Abegg
- Pharmacia Discovery Research, 700 Chesterfield Village Parkway North, St Louis, MO 63198, USA
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Heller SR, Amiel SA, Evans ML, Kong MF, Macdonald IA, Peacey SR. Does insulin lispro preserve the physiological defences to hypoglycaemia during intensive insulin therapy with a conventional basal bolus regimen? Diabetes Obes Metab 2002; 4:106-12. [PMID: 11940107 DOI: 10.1046/j.1463-1326.2002.00186.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
AIM Insulin lispro used in an intensive basal/bolus regimen produces equivalent glycaemic control to human-soluble insulin but reduces rates of hypoglycaemia. We tested the hypothesis that the use of rapid-acting analogues might prevent the development of defective hypoglycaemic counterregulation during intensive insulin therapy. METHODS Ten patients with type 1 diabetes (four female, mean age 33 +/- 3 years, diabetes duration 12 +/- 2 years) participated in an open, randomized cross-over study, with 2 months run-in and 4-month treatment periods using either lispro or human-soluble insulin before meals and human NPH insulin (NPH) at night. The total of reported hypoglycaemic episodes (lispro vs. soluble, 123 vs. 128) and HbA(1c) (6.1 +/- 0.2 vs. 6.6 +/- 0.2%) were similar during both treatments. At the end of each period, we measured symptomatic, counterregulatory and cognitive responses, and glycaemic thresholds during hypoglycaemia, induced with a hyperinsulinaemic clamp (blood glucose of 5, 4.5, 3.5 and 2.5 mmol/l). RESULTS We found similar overall responses of adrenaline, cortisol, growth hormone and total symptom score. Glycaemic thresholds for rises in adrenaline (3.1 +/- 0.2 vs. 3.1 +/- 0.2 mmol/l, p = 0.76), cortisol (2.2 +/- 0.1 vs. 2.2 +/- 0.1 mmol/l, p = 0.16), growth hormone (3.3 +/- 0.15 vs. 2.9 +/- 0.2 mmol/l, p = 0.13), symptoms (3.2 +/- 0.2 vs. 3.3 +/- 0.1 mmol/l, p = 0.051) and impaired cognitive function (3.0 +/- 0.2 vs. 3.0 +/-0.2 mmol/l, p = 0.20) were also similar. CONCLUSION Four months of intensive treatment, with insulin lispro used pre-prandially and isophane at night, produced relatively preserved but equivalent physiological responses to hypoglycaemia as those on soluble insulin. Longer periods of treatment or alternative regimens may be necessary to demonstrate beneficial effects on hypoglycaemic physiological responses.
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26
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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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Affiliation(s)
- E M Soffin
- Psychiatry Centre of Excellence for Drug Discovery, GlaxoSmithKline, New Frontiers Science Park, Third Avenue, Harlow, CM19 5AW, Essex, UK.
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27
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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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Affiliation(s)
- D Young
- Laboratory for Statistical Neuroimaging, Mailman Research Center, McLean Hospital, 115 Mill St. Belmont, MA 02478, USA
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28
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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] [What about the content of this article? (0)] [Affiliation(s)] [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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Affiliation(s)
- A R Calver
- Department of Neuroscience Research, SmithKline Beecham Pharmaceuticals, New Frontiers Science Park, Third Avenue, Essex CM19 5AW, Harlow, UK.
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29
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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] [What about the content of this article? (0)] [Affiliation(s)] [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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Affiliation(s)
- R A Anderson
- Department of Cardiology, Wales Heart Research Institute, University of Wales College of Medicine, Heath Park, CF44XN, Cardiff, UK.
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30
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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] [What about the content of this article? (0)] [Affiliation(s)] [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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Affiliation(s)
- K J Charles
- Neurology CEDD, GlaxoSmithKline Pharmaceuticals, New Frontiers Science Park, Harlow, Essex, UK
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31
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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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Affiliation(s)
- D J Cutler
- Diabetes & Endocrinology Research Group, Department of Medicine, University of Liverpool, L69 3GA, Liverpool, England, UK
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32
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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] [What about the content of this article? (0)] [Affiliation(s)] [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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Affiliation(s)
- X J Cai
- Diabetes and Endocrinology Research Group, University of Liverpool, UK.
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33
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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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Affiliation(s)
- C Wolverton
- Department of Plant Biology, The Ohio State University, Columbus, OH 43210, USA
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34
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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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Affiliation(s)
- J V Juturi
- Harry S. Truman Memorial Veterans Affairs Medical Center, Columbia, Missouri, USA
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35
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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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Affiliation(s)
- M L Evans
- School of Nursing, University of North Carolina Greensboro, 27402-6172, USA
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36
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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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Affiliation(s)
- M L Evans
- Department of Internal Medicine, Diabetes Endocrinology Research Center, Yale University School of Medicine, New Haven, Connecticut 06520, USA.
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37
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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] [What about the content of this article? (0)] [Affiliation(s)] [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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Affiliation(s)
- A M Ray
- Department of Neuroscience Research, SmithKline Beecham Pharmaceuticals, New Frontiers Science Park (North), Third Avenue, Harlow, CM19 5AW, Essex, UK.
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38
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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 Physiol 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] [What about the content of this article? (0)] [Affiliation(s)] [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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Affiliation(s)
- J L Mullen
- Department of Plant Biology, The Ohio State University, Columbus 43210-1293, USA.
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39
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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. Biol Sci Space 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] [What about the content of this article? (0)] [Affiliation(s)] [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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Affiliation(s)
- C Wolverton
- Department of Plant Biology, The Ohio State University, Columbus 43210, USA
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40
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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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Affiliation(s)
- L J Sievert
- Department of Radiology, University of Missouri Health Sciences Center, Columbia, USA
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41
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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. J Plant Res 1999; 112:493-496. [PMID: 11543178 DOI: 10.1007/pl00013905] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [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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Affiliation(s)
- C Wolverton
- Department of Plant Biology, The Ohio State University, Columbus 43210, USA
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42
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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] [What about the content of this article? (0)] [Affiliation(s)] [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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Affiliation(s)
- D J Cutler
- Department of Medicine, University of Liverpool, England.
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43
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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: 877] [Impact Index Per Article: 35.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [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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Affiliation(s)
- J J Hagan
- Neuroscience Research, Europe, SmithKline Beecham Pharmaceuticals, New Frontiers Science Park, Third Avenue, Harlow, Essex, United Kingdom CM19 5AW.
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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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Affiliation(s)
- M L Evans
- Department of Gynecology and Obstetrics, Loma Linda University School of Medicine 92350, USA
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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] [What about the content of this article? (0)] [Affiliation(s)] [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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Affiliation(s)
- M Caeser
- Neuroscience Research, SmithKline Beecham Pharmaceuticals, Harlow, Essex, UK
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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] [What about the content of this article? (0)] [Affiliation(s)] [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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Affiliation(s)
- K C Oberg
- Department of Pathology and Human Anatomy, Loma Linda University School of Medicine, Loma Linda, CA 92350, USA
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47
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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 Physiol 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] [What about the content of this article? (0)] [Affiliation(s)] [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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Affiliation(s)
- J L Mullen
- Department of Plant Biology, The Ohio State University, Columbus, Ohio 43210-1293, USA
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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] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Affiliation(s)
- M L Evans
- Nursing Service, Presbyterian Hospital of Dallas, TX, USA
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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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Affiliation(s)
- M L Evans
- University of North Carolina at Greensboro, USA
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