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Li L, Guo Y, Chen C, Wang Z, Liu Z. Mechanisms of hyponatremia and diabetes insipidus after acute spinal cord injury: a critical review. Chin Neurosurg J 2023; 9:32. [PMID: 37968769 PMCID: PMC10647149 DOI: 10.1186/s41016-023-00347-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2023] [Accepted: 10/24/2023] [Indexed: 11/17/2023] Open
Abstract
The incidence of hyponatremia after spinal cord injury was reported to be between 25 and 80%. Hyponatremia can lead to a variety of clinical symptoms, from mild to severe and even life-threatening. Hyponatremia is often associated with diabetes insipidus, which refers to insufficient arginine vasopressin (AVP) secretion or defective renal response to AVP, with clinical manifestations of syndromes such as hypoosmolality, polydipsia, and polydipsia. Recent mechanistic studies on hyponatremia and diabetes insipidus after acute spinal cord injury have been performed in isolation, without integrating the above two symptoms into different pathological manifestations that occur in the same injury state and without considering the acute spinal cord injury patient's condition as a whole. The therapeutic principles of CSWS and SIADH are in opposition to one another. It is not easy to identify the mechanism of hyponatremia in clinical practice, which makes selecting the treatment difficult. According to the existing theories, treatments for hyponatremia and diabetes insipidus together are contraindicated, whether the mechanism of hyponatremia is thought to be CSWS or SIADH. In this paper, we review the mechanism of these two pathological manifestations and suggest that our current understanding of the mechanisms of hyponatremia and diabetes insipidus after high acute cervical SCI is insufficient, and it is likely that there are other undetected pathogenetic mechanisms.
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Affiliation(s)
- Lianhua Li
- Department of Orthopedics, the Fourth Medical Center of PLA General Hospital, Beijing, China.
| | - Yanhui Guo
- Department of Orthopedics, the Fourth Medical Center of PLA General Hospital, Beijing, China
| | - Chen Chen
- Department of Orthopedics, the Fourth Medical Center of PLA General Hospital, Beijing, China
| | - Zhonghe Wang
- Department of Orthopedics, the Fourth Medical Center of PLA General Hospital, Beijing, China
| | - Zhi Liu
- Department of Orthopedics, the Fourth Medical Center of PLA General Hospital, Beijing, China
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2
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Hubscher CH, Gumbel JH, Armstrong JE, Montgomery LR. Impact of activity-based recovery training and desmopressin on spinal cord injury-induced polyuria in Wistar rats. J Spinal Cord Med 2023; 46:910-916. [PMID: 35604340 PMCID: PMC10653760 DOI: 10.1080/10790268.2022.2069538] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
Abstract
Activity-based recovery training (ABRT) reverses spinal cord injury (SCI) induced polyuria and alterations of biomarkers involved with fluid balance, including expression levels of kidney vasopressin 2 receptors. However, void volumes do not return to pre-injury baseline levels, indicating a combinatorial approach may be necessary. In the current study, acute effects of a pharmacological intervention versus placebo were examined in male rats that had received 70 daily ABRT sessions. The treatment, desmopressin (DDAVP - synthetic analogue of arginine vasopressin), an antidiuretic therapy used for the management of bedwetting in children and central diabetes insipidus, has previously shown some promise in a few limited cohorts of SCI individuals having nocturnal polyuria. A total of 70 sessions of ABRT over a 10-week timeframe again reduced the overproduction of urine, but not completely to pre-SCI baseline levels. DDAVP treatment maintained but did not further reduce the level of urine output in the ABRT group without continuous exercise, demonstrating either intervention/treatment alone is effective, despite no additive effect. Although intake did not change from pre-injury levels despite polyuria, DDAVP treatment also reduced drink volume. Further studies are needed as the mechanisms underlying changes in fluid and solute balance are likely multi-factorial involving a complex interaction between the neural (both central and peripheral) control of systems mediating thirst, urinary output, and cardiovascular regulation.
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Affiliation(s)
- Charles H. Hubscher
- Department of Anatomical Sciences & Neurobiology, University of Louisville, Louisville, KY, USA
- Kentucky Spinal Cord Research Center, Louisville, KY, USA
| | - Jason H. Gumbel
- Department of Anatomical Sciences & Neurobiology, University of Louisville, Louisville, KY, USA
| | - James E. Armstrong
- Department of Anatomical Sciences & Neurobiology, University of Louisville, Louisville, KY, USA
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3
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Osei-Owusu P, Collyer E, Dahlen SA, Echols Adams RE, Tom VJ. Maladaptation of Renal Hemodynamics Contributes to Kidney Dysfunction Resulting from Thoracic Spinal Cord Injury in Mice. Am J Physiol Renal Physiol 2022; 323:F120-F140. [PMID: 35658716 PMCID: PMC9306783 DOI: 10.1152/ajprenal.00072.2022] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Renal dysfunction is a hallmark of spinal cord injury (SCI). Several SCI sequalae are implicated, however, the exact pathogenic mechanism of renal dysfunction is unclear. Herein, we found that T3 (T3Tx) or T10 (T10Tx) complete thoracic spinal cord transection induced hypotension, bradycardia, and hypothermia immediately after injury. T3Tx-induced hypotension but not bradycardia or hypothermia slowly recovered to levels in T10Tx SCI and uninjured mice ~16 h after injury as determined by continuous radiotelemetry monitoring. Both types of thoracic SCI led to a marked decrease in albuminuria and proteinuria in all phases of SCI, while the kidney injury marker, NGAL, rapidly increased in the acute phase, remaining elevated in the chronic phase of T3Tx SCI. Renal interstitial and vascular elastin fragmentation after SCI were worsened during chronic T3Tx SCI. In the chronic phase, renal vascular resistance response to a step increase in renal perfusion pressure or a bolus injection of Ang II or NE was almost completely abolished after T3Tx SCI. Bulk RNAseq analysis showed enrichment of genes involved in extracellular matrix (ECM) remodeling and chemokine signaling in the kidney from T3Tx SCI mice. Serum levels of interleukin 6 was elevated in the acute but not chronic phase of T3Tx and T10Tx SCI, while serum amyloid A1 level was elevated in both acute and chronic phases. We conclude that tissue fibrosis and hemodynamic impairment are involved in renal dysfunction resulting from thoracic SCI; these pathological alterations, exacerbated by high thoracic-level injury, is mediated at least partly by renal microvascular ECM remodeling.
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Affiliation(s)
- Patrick Osei-Owusu
- Physiology & Biophysics, Case Western Reserve University, Cleveland, OH, United States
| | - Eileen Collyer
- Neurobiology and Anatomy, Drexel University, Philadelphia, PA, United States
| | - Shelby A Dahlen
- Physiology & Biophysics, Case Western Reserve University, Cleveland, OH, United States
| | - Raisa E Echols Adams
- Physiology & Biophysics, Case Western Reserve University, Cleveland, OH, United States
| | - Veronica J Tom
- Neurobiology and Anatomy, Drexel University, Philadelphia, PA, United States
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Sun XS, Wang XL, Bai M, Song C, Eaton DC, Yue Q, Martin KK, Cai H, Garraway S, Wang LH, Ma HP. Atrial Natriuretic Peptide and the Epithelial Sodium Channel Contribute to Spinal Cord Injury-Induced Polyuria in Mice. J Neurotrauma 2022; 39:724-734. [PMID: 35216518 PMCID: PMC9081061 DOI: 10.1089/neu.2021.0305] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Polyuria is found in patients with spinal cord injury (SCI). However, the underlying cellular and molecular mechanism is unknown. Here, we show that mice had elevated urine for 7 days after T10 contusion. Using multi-photon confocal microscopy, we performed intra-vital imaging experiments to evaluate water reabsorption in kidney tubules by examining fluorescent intensity in the lumen of the distal tubule from live mice. The data show that SCI significantly reduced the concentrating function of kidney tubules. The reduced water reabsorption appears to be mediated by atrial natriuretic peptide (ANP) because SCI increased the expression levels of both ANP and natriuretic peptide receptor A (NPR-A) in the kidney cortex. Our patch-clamp single-channel recordings from split-open distal tubules show that SCI decreased the activity of the epithelial sodium channel (ENaC). Western blot combined with confocal microscopy data show that the levels of 70 kD γ-ENaC, which is an active isoform because of proteolytic cleavage, were significantly reduced in distal tubule principal cells. An NPR-A inhibitor (A71915) given intravenously eliminated the effects of SCI on ENaC and polyuria. These data together with previous studies suggest that SCI causes polyuria, probably by reducing ENaC activity through elevating ANP and NPR-A. Further investigation of the signal transduction pathways may provide useful information for discovering an efficient drug to treat SCI-induced polyuria.
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Affiliation(s)
- Xue-Song Sun
- Department of Neurology, the Second Affiliated Hospital of Harbin Medical University, Harbin, People's Republic of China
- Department of Cell Biology, Emory University School of Medicine, Atlanta, Georgia, USA
| | - Xiao-Long Wang
- Department of Orthopedic Surgery, Cancer Hospital of Harbin Medical University, Harbin, People's Republic of China
| | - Ming Bai
- Department of Neurology, the Second Affiliated Hospital of Harbin Medical University, Harbin, People's Republic of China
| | - Chang Song
- Department of Neurology, the Second Affiliated Hospital of Harbin Medical University, Harbin, People's Republic of China
- Renal Division, Emory University School of Medicine, Atlanta, Georgia, USA
| | - Douglas C. Eaton
- Renal Division, Emory University School of Medicine, Atlanta, Georgia, USA
| | - Qiang Yue
- Renal Division, Emory University School of Medicine, Atlanta, Georgia, USA
| | - Karmarcha K. Martin
- Department of Cell Biology, Emory University School of Medicine, Atlanta, Georgia, USA
| | - Hui Cai
- Renal Division, Emory University School of Medicine, Atlanta, Georgia, USA
- Section of Nephrology, Atlanta VA Medical Center, Decatur, Georgia, USA
| | - Sandra Garraway
- Department of Cell Biology, Emory University School of Medicine, Atlanta, Georgia, USA
| | - Li-Hua Wang
- Department of Neurology, the Second Affiliated Hospital of Harbin Medical University, Harbin, People's Republic of China
| | - He-Ping Ma
- Department of Cell Biology, Emory University School of Medicine, Atlanta, Georgia, USA
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Gumbel JH, Yang CB, Hubscher CH. Timeline of Changes in Biomarkers Associated with Spinal Cord Injury-Induced Polyuria. Neurotrauma Rep 2021; 2:462-475. [PMID: 34901942 PMCID: PMC8655813 DOI: 10.1089/neur.2021.0046] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Deficits in upper and lower urinary tract function, which include detrusor overactivity, urinary incontinence, detrusor-sphincter dyssynergia, and polyuria, are among the leading issues that arise after spinal cord injury (SCI) affecting quality of life. Given that overproduction of urine (polyuria) has been shown to be associated with an imbalance in key regulators of body fluid homeostasis, the current study examined the timing of changes in levels of various relevant hormones, peptides, receptors, and channels post-contusion injury in adult male Wistar rats. The results show significant up- or downregulation at various time points, beginning at 7 days post-injury, in levels of urinary atrial natriuretic peptide, serum arginine vasopressin (AVP), kidney natriuretic peptide receptor-A, kidney vasopressin-2 receptor, kidney aquaporin-2 channels, and kidney epithelial sodium channels (β- and γ-, but not α-, subunits). The number of AVP-labeled neurons in the hypothalamus (supraoptic and -chiasmatic, but not paraventricular, nuclei) was also significantly altered at one or more time points. These data show significant fluctuations in key biomarkers involved in body fluid homeostasis during the post-SCI secondary injury phase, suggesting that therapeutic interventions (e.g., desmopressin, a synthetic analogue of AVP) should be considered early post-SCI.
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Affiliation(s)
- Jason H. Gumbel
- Department of Anatomical Sciences and Neurobiology, University of Louisville, Louisville, Kentucky, USA
| | - Cui Bo Yang
- Department of Anatomical Sciences and Neurobiology, University of Louisville, Louisville, Kentucky, USA
| | - Charles H. Hubscher
- Department of Anatomical Sciences and Neurobiology, University of Louisville, Louisville, Kentucky, USA
- Kentucky Spinal Cord Injury Research Center, University of Louisville, Louisville, Kentucky, USA
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Herrity AN, Aslan SC, Ugiliweneza B, Mohamed AZ, Hubscher CH, Harkema SJ. Improvements in Bladder Function Following Activity-Based Recovery Training With Epidural Stimulation After Chronic Spinal Cord Injury. Front Syst Neurosci 2021; 14:614691. [PMID: 33469421 PMCID: PMC7813989 DOI: 10.3389/fnsys.2020.614691] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2020] [Accepted: 12/03/2020] [Indexed: 12/27/2022] Open
Abstract
Spinal cord injury (SCI) results in profound neurologic impairment with widespread deficits in sensorimotor and autonomic systems. Voluntary and autonomic control of bladder function is disrupted resulting in possible detrusor overactivity, low compliance, and uncoordinated bladder and external urethral sphincter contractions impairing storage and/or voiding. Conservative treatments managing neurogenic bladder post-injury, such as oral pharmacotherapy and catheterization, are important components of urological surveillance and clinical care. However, as urinary complications continue to impact long-term morbidity in this population, additional therapeutic and rehabilitative approaches are needed that aim to improve function by targeting the recovery of underlying impairments. Several human and animal studies, including our previously published reports, have documented gains in bladder function due to activity-based recovery strategies, such as locomotor training. Furthermore, epidural stimulation of the spinal cord (scES) combined with intense activity-based recovery training has been shown to produce volitional lower extremity movement, standing, as well as improve the regulation of cardiovascular function. In our center, several participants anecdotally reported improvements in bladder function as a result of training with epidural stimulation configured for motor systems. Thus, in this study, the effects of activity-based recovery training in combination with scES were tested on bladder function, resulting in improvements in overall bladder storage parameters relative to a control cohort (no intervention). However, elevated blood pressure elicited during bladder distention, characteristic of autonomic dysreflexia, was not attenuated with training. We then examined, in a separate, large cross-sectional cohort, the interaction between detrusor pressure and blood pressure at maximum capacity, and found that the functional relationship between urinary bladder distention and blood pressure regulation is disrupted. Regardless of one’s bladder emptying method (indwelling suprapubic catheter vs. intermittent catheterization), autonomic instability can play a critical role in the ability to improve bladder storage, with SCI enhancing the vesico-vascular reflex. These results support the role of intersystem stimulation, integrating scES for both bladder and cardiovascular function to further improve bladder storage.
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Affiliation(s)
- April N Herrity
- Kentucky Spinal Cord Injury Research Center, University of Louisville, Louisville, KY, United States.,Department of Neurological Surgery, University of Louisville, Louisville, KY, United States
| | - Sevda C Aslan
- Kentucky Spinal Cord Injury Research Center, University of Louisville, Louisville, KY, United States.,Department of Neurological Surgery, University of Louisville, Louisville, KY, United States
| | - Beatrice Ugiliweneza
- Kentucky Spinal Cord Injury Research Center, University of Louisville, Louisville, KY, United States.,Department of Neurological Surgery, University of Louisville, Louisville, KY, United States
| | - Ahmad Z Mohamed
- Department of Urology, University of Louisville, Louisville, KY, United States
| | - Charles H Hubscher
- Kentucky Spinal Cord Injury Research Center, University of Louisville, Louisville, KY, United States.,Department of Anatomical Sciences and Neurobiology, University of Louisville, Louisville, KY, United States
| | - Susan J Harkema
- Kentucky Spinal Cord Injury Research Center, University of Louisville, Louisville, KY, United States.,Department of Neurological Surgery, University of Louisville, Louisville, KY, United States
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Gumbel JH, Montgomery LR, Yang CB, Hubscher CH. Activity-Based Training Reverses Spinal Cord Injury-Induced Changes in Kidney Receptor Densities and Membrane Proteins. J Neurotrauma 2019; 37:555-563. [PMID: 31456470 DOI: 10.1089/neu.2019.6670] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Complications in upper and lower urinary function arise after spinal cord injury (SCI), which creates a significant impact on quality of life for those affected. One upper urinary complication is SCI-induced polyuria, or the overproduction of urine, of which the underlying mechanisms have yet to be elucidated. Activity-based training (ABT) has been utilized in both animal and clinical settings as a rehabilitative therapy to improve many issues that arise after SCI, including more recently urogenital function. The goal of the current study was to identify potential mechanisms contributing to previously identified improvements in polyuria with ABT, using a male rat moderate-severe spinal contusion model. Although ABT had no significant effect on reversing injury-induced alterations of serum arginine vasopressin and urinary atrial natriuretic peptide levels, there was a dramatic effect upon the receptors of these fluid balance hormones (vasopressin receptor 2 and natriuretic peptide A receptor), as well as kidney aquaporin 2 and sodium channels. ABT changes in densities of key receptors and kidney membrane proteins involved in fluid balance after chronic SCI support the likelihood of multiple mechanisms through which exercise can positively influence urinary tract function after SCI. By understanding the mechanisms, amount, and timing regarding how ABT improves different aspects of urinary function, more targeted training strategies can be developed to optimize the functional gains within the SCI population.
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Affiliation(s)
- Jason H Gumbel
- Department of Anatomical Sciences and Neurobiology, University of Louisville, Louisville, Kentucky
| | - Lynnette R Montgomery
- Department of Anatomical Sciences and Neurobiology, University of Louisville, Louisville, Kentucky.,Kentucky Spinal Cord Injury Rehabilitation Center, University of Louisville, Louisville, Kentucky
| | - Cui Bo Yang
- Department of Anatomical Sciences and Neurobiology, University of Louisville, Louisville, Kentucky
| | - Charles H Hubscher
- Department of Anatomical Sciences and Neurobiology, University of Louisville, Louisville, Kentucky.,Kentucky Spinal Cord Injury Rehabilitation Center, University of Louisville, Louisville, Kentucky
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Holmes GM, Hubscher CH, Krassioukov A, Jakeman LB, Kleitman N. Recommendations for evaluation of bladder and bowel function in pre-clinical spinal cord injury research. J Spinal Cord Med 2019; 43:165-176. [PMID: 31556844 PMCID: PMC7054945 DOI: 10.1080/10790268.2019.1661697] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Objective: In order to encourage the inclusion of bladder and bowel outcome measures in preclinical spinal cord injury (SCI) research, this paper identifies and categorizes 1) fundamental, 2) recommended, 3) supplemental and 4) exploratory sets of outcome measures for pre-clinical assessment of bladder and bowel function with broad applicability to animal models of SCI.Methods: Drawing upon the collective research experience of autonomic physiologists and informed in consultation with clinical experts, a critical assessment of currently available bladder and bowel outcome measures (histological, biochemical, in vivo functional, ex vivo physiological and electrophysiological tests) was made to identify the strengths, deficiencies and ease of inclusion for future studies of experimental SCI.Results: Based upon pre-established criteria generated by the Neurogenic Bladder and Bowel Working Group that included history of use in experimental settings, citations in the literature by multiple independent groups, ease of general use, reproducibility and sensitivity to change, three fundamental measures each for bladder and bowel assessments were identified. Briefly defined, these assessments centered upon tissue morphology, voiding efficiency/volume and smooth muscle-mediated pressure studies. Additional assessment measures were categorized as recommended, supplemental or exploratory based upon the balance between technical requirements and potential mechanistic insights to be gained by the study.Conclusion: Several fundamental assessments share reasonable levels of technical and material investment, including some that could assess bladder and bowel function non-invasively and simultaneously. Such measures used more inclusively across SCI studies would advance progress in this high priority area. When complemented with a few additional investigator-selected study-relevant supplemental measures, they are highly recommended for research programs investigating the efficacy of therapeutic interventions in preclinical animal models of SCI that have a bladder and/or bowel focus.
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Affiliation(s)
- Gregory M. Holmes
- Neural and Behavioral Sciences, Pennsylvania State University College of Medicine, Hershey, Pennsylvania, USA,Correspondence to: Gregory M. Holmes, Neural and Behavioral Sciences, Pennsylvania State University College of Medicine, 500 University Dr., Hershey, PA 17036, USA. ;
| | - Charles H. Hubscher
- Department of Anatomical Sciences and Neurobiology, University of Louisville, Louisville, Kentucky, USA,Kentucky Spinal Cord Injury Research Center, University of Louisville, Louisville, Kentucky, USA
| | - Andrei Krassioukov
- ICORD, University of British Columbia, GF Strong Rehabilitation Centre, Vancouver, Canada
| | - Lyn B. Jakeman
- National Institute of Neurological Disorders and Stroke, Bethesda, Maryland, USA
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Viaene A, Roggeman S, Goessaert AS, Kessler TM, Mehnert U, Besien VV, De Muynck M, Everaert K. Conservative treatment for leg oedema and the effect on nocturnal polyuria in patients with spinal cord injury. BJU Int 2019; 123:E43-E50. [DOI: 10.1111/bju.14672] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Annick Viaene
- Department of Physical Medicine and Rehabilitation; Ghent University Hospital; Gent Belgium
| | - Saskia Roggeman
- Department of Urology; Ghent University Hospital; Ghent University; Gent Belgium
| | - An-Sofie Goessaert
- Department of Urology; Ghent University Hospital; Ghent University; Gent Belgium
| | - Thomas M. Kessler
- Department of Neuro-Urology; Spinal Cord Injury Center & Research; Balgrist University Hospital; University of Zürich; Zürich Switzerland
| | - Ulrich Mehnert
- Department of Neuro-Urology; Spinal Cord Injury Center & Research; Balgrist University Hospital; University of Zürich; Zürich Switzerland
| | - Vickie Van Besien
- Department of Rehabilitation Sciences and Physiotherapy; Ghent University Hospital; Gent Belgium
| | - Martine De Muynck
- Department of Physical Medicine and Rehabilitation; Ghent University Hospital; Gent Belgium
| | - Karel Everaert
- Department of Urology; Ghent University Hospital; Ghent University; Gent Belgium
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Goh MY, Millard MS, Wong ECK, Berlowitz DJ, Graco M, Schembri RM, Brown DJ, Frauman AG, O’Callaghan CJ. Comparison of diurnal blood pressure and urine production between people with and without chronic spinal cord injury. Spinal Cord 2018; 56:847-855. [DOI: 10.1038/s41393-018-0081-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2017] [Revised: 02/08/2018] [Accepted: 02/12/2018] [Indexed: 12/20/2022]
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