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Scott SR, Singh K, Yu Q, Sen CK, Wang M. Sex as Biological Variable in Cardiac Mitochondrial Bioenergetic Responses to Acute Stress. Int J Mol Sci 2022; 23:9312. [PMID: 36012574 PMCID: PMC9409303 DOI: 10.3390/ijms23169312] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [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] [Subscribe] [Scholar Register] [Received: 07/06/2022] [Revised: 08/10/2022] [Accepted: 08/17/2022] [Indexed: 11/29/2022] Open
Abstract
Cardiac dysfunction/damage following trauma, shock, sepsis, and ischemia impacts clinical outcomes. Acute inflammation and oxidative stress triggered by these injuries impair mitochondria, which are critical to maintaining cardiac function. Despite sex dimorphisms in consequences of these injuries, it is unclear whether mitochondrial bioenergetic responses to inflammation/oxidative stress are sex-dependent. We hypothesized that sex disparity in mitochondrial bioenergetics following TNFα or H2O2 exposure is responsible for reported sex differences in cardiac damage/dysfunction. Methods and Results: Cardiomyocytes isolated from age-matched adult male and female mice were subjected to 1 h TNFα or H2O2 challenge, followed by detection of mitochondrial respiration capacity using the Seahorse XF96 Cell Mito Stress Test. Mitochondrial membrane potential (ΔΨm) was analyzed using JC-1 in TNFα-challenged cardiomyocytes. We found that cardiomyocytes isolated from female mice displayed a better mitochondrial bioenergetic response to TNFα or H2O2 than those isolated from male mice did. TNFα decreased ΔΨm in cardiomyocytes isolated from males but not from females. 17β-estradiol (E2) treatment improved mitochondrial metabolic function in cardiomyocytes from male mice subjected to TNFα or H2O2 treatment. Conclusions: Cardiomyocyte mitochondria from female mice were more resistant to acute stress than those from males. The female sex hormone E2 treatment protected cardiac mitochondria against acute inflammatory and oxidative stress.
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Affiliation(s)
- Susan R. Scott
- Department of Surgery, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Kanhaiya Singh
- Department of Surgery, Indiana University School of Medicine, Indianapolis, IN 46202, USA
- Indiana Center for Regenerative Medicine and Engineering, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Qing Yu
- Department of Surgery, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Chandan K. Sen
- Department of Surgery, Indiana University School of Medicine, Indianapolis, IN 46202, USA
- Indiana Center for Regenerative Medicine and Engineering, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Meijing Wang
- Department of Surgery, Indiana University School of Medicine, Indianapolis, IN 46202, USA
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Lee Y, Singh J, Scott SR, Ellis B, Zorlutuna P, Wang M. A Recombinant Dimethylarginine Dimethylaminohydrolase-1-Based Biotherapeutics to Pharmacologically Lower Asymmetric Dimethyl Arginine, thus Improving Postischemic Cardiac Function and Cardiomyocyte Mitochondrial Activity. Mol Pharmacol 2022; 101:226-235. [PMID: 35042831 PMCID: PMC11033929 DOI: 10.1124/molpharm.121.000394] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Accepted: 01/16/2022] [Indexed: 11/22/2022] Open
Abstract
High serum levels of asymmetric dimethyl arginine (ADMA) are associated with cardiovascular disease and mortality. Pharmacological agents to specifically lower ADMA and their potential impact on cardiovascular complications are not known. In this study, we aimed to investigate the effect of specific lowering of ADMA on myocardial response to ischemia-reperfusion injury (I/R) and direct effects on cardiomyocyte function. Effects of recombinant dimethylarginine dimethylaminohydrolase (rDDAH)-1 on I/R injury were determined using isolated mouse heart preparation. Respiration capacity and mitochondrial reactive oxygen species (ROS) generation were determined on mouse cardiomyocytes. Our results show that lowering ADMA by rDDAH-1 treatment resulted in improved recovery of cardiac function and reduction in myocardial infarct size in mouse heart response to I/R injury (control 22.24 ±4.60% versus rDDAH-1 15.90 ±4.23%, P < 0.01). In mouse cardiomyocytes, rDDAH-1 treatment improved ADMA-induced dysregulation of respiration capacity and decreased mitochondrial ROS. Furthermore, in human induced pluripotent stem cell (hiPSC)-derived cardiomyocytes with impaired contractility under hypoxia and high ADMA, rDDAH-1 treatment improved recovery and beating frequency (P < 0.05). rDDAH-1 treatment selectively modified I/R-induced myocardial cytokine expression, resulting in reduction in proinflammatory cytokine IL-17A (P < 0.001) and increased expression of anti-inflammatory cytokines IL-10 and IL-13 (P < 0.01). Further in vitro studies showed that IL-17A was the predominant and common cytokine modulated by ADMA-DDAH pathway in heart, cardiomyocytes, and endothelial cells. These studies show that lowering ADMA by pharmacological treatment with rDDAH-1 reduced I/R injury, improved cardiac function, and ameliorated cardiomyocyte bioenergetics and beating activity. These effects may be attributable to ADMA lowering in cardiomyocytes and preservation of cardiomyocyte mitochondrial function. SIGNIFICANCE STATEMENT: The pathological role of asymmetric dimethyl arginine (ADMA) has been demonstrated by its association with cardiovascular disease and mortality. Currently, pharmacological drugs to specifically lower ADMA are not available. The present study provides the first evidence that lowering of ADMA by recombinant recombinant dimethylarginine dimethylaminohydrolase (rDDAH)-1 improved postischemic cardiac function and cardiomyocyte bioenergetics and beating activity. Our studies suggest that lowering of ADMA by pharmacologic treatment offers opportunity to develop new therapies for the treatment of cardiovascular and renal disease.
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Affiliation(s)
- Young Lee
- Indiana Center for Biomedical Innovation, Indianapolis, Indiana (Y.L., J.S.); Indiana University School of Medicine, Indianapolis, Indiana (J.S.); Department of Surgery, Indiana University, School of Medicine, Indianapolis, Indiana (S.R.S., M.W.); Bioengineering Graduate Program (B.E., P.Z.) and Aerospace and Mechanical Engineering Department (P.Z.), University of Notre Dame, Notre Dame, Indiana; and Vasculonics LLC, Indianapolis, Indiana (J.S.)
| | - Jaipal Singh
- Indiana Center for Biomedical Innovation, Indianapolis, Indiana (Y.L., J.S.); Indiana University School of Medicine, Indianapolis, Indiana (J.S.); Department of Surgery, Indiana University, School of Medicine, Indianapolis, Indiana (S.R.S., M.W.); Bioengineering Graduate Program (B.E., P.Z.) and Aerospace and Mechanical Engineering Department (P.Z.), University of Notre Dame, Notre Dame, Indiana; and Vasculonics LLC, Indianapolis, Indiana (J.S.)
| | - Susan R Scott
- Indiana Center for Biomedical Innovation, Indianapolis, Indiana (Y.L., J.S.); Indiana University School of Medicine, Indianapolis, Indiana (J.S.); Department of Surgery, Indiana University, School of Medicine, Indianapolis, Indiana (S.R.S., M.W.); Bioengineering Graduate Program (B.E., P.Z.) and Aerospace and Mechanical Engineering Department (P.Z.), University of Notre Dame, Notre Dame, Indiana; and Vasculonics LLC, Indianapolis, Indiana (J.S.)
| | - Bradley Ellis
- Indiana Center for Biomedical Innovation, Indianapolis, Indiana (Y.L., J.S.); Indiana University School of Medicine, Indianapolis, Indiana (J.S.); Department of Surgery, Indiana University, School of Medicine, Indianapolis, Indiana (S.R.S., M.W.); Bioengineering Graduate Program (B.E., P.Z.) and Aerospace and Mechanical Engineering Department (P.Z.), University of Notre Dame, Notre Dame, Indiana; and Vasculonics LLC, Indianapolis, Indiana (J.S.)
| | - Pinar Zorlutuna
- Indiana Center for Biomedical Innovation, Indianapolis, Indiana (Y.L., J.S.); Indiana University School of Medicine, Indianapolis, Indiana (J.S.); Department of Surgery, Indiana University, School of Medicine, Indianapolis, Indiana (S.R.S., M.W.); Bioengineering Graduate Program (B.E., P.Z.) and Aerospace and Mechanical Engineering Department (P.Z.), University of Notre Dame, Notre Dame, Indiana; and Vasculonics LLC, Indianapolis, Indiana (J.S.)
| | - Meijing Wang
- Indiana Center for Biomedical Innovation, Indianapolis, Indiana (Y.L., J.S.); Indiana University School of Medicine, Indianapolis, Indiana (J.S.); Department of Surgery, Indiana University, School of Medicine, Indianapolis, Indiana (S.R.S., M.W.); Bioengineering Graduate Program (B.E., P.Z.) and Aerospace and Mechanical Engineering Department (P.Z.), University of Notre Dame, Notre Dame, Indiana; and Vasculonics LLC, Indianapolis, Indiana (J.S.)
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Scott SR, March KL, Wang IW, Singh K, Liu J, Turrentine M, Sen CK, Wang M. Bone marrow- or adipose-mesenchymal stromal cell secretome preserves myocardial transcriptome profile and ameliorates cardiac damage following ex vivo cold storage. J Mol Cell Cardiol 2022; 164:1-12. [PMID: 34774548 PMCID: PMC8860861 DOI: 10.1016/j.yjmcc.2021.11.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/11/2021] [Revised: 10/24/2021] [Accepted: 11/03/2021] [Indexed: 12/11/2022]
Abstract
BACKGROUND Heart transplantation, a life-saving approach for patients with end-stage heart disease, is limited by shortage of donor organs. While prolonged storage provides more organs, it increases the extent of ischemia. Therefore, we seek to understand molecular mechanisms underlying pathophysiological changes of donor hearts during prolonged storage. Additionally, considering mesenchymal stromal cell (MSC)-derived paracrine protection, we aim to test if MSC secretome preserves myocardial transcriptome profile and whether MSC secretome from a certain source provides the optimal protection in donor hearts during cold storage. METHODS AND RESULTS Isolated mouse hearts were divided into: no cold storage (control), 6 h cold storage (6 h-I), 6 h-I + conditioned media from bone marrow MSCs (BM-MSC CM), and 6 h-I + adipose-MSC CM (Ad-MSC CM). Deep RNA sequencing analysis revealed that compared to control, 6 h-I led to 266 differentially expressed genes, many of which were implicated in modulating mitochondrial performance, oxidative stress response, myocardial function, and apoptosis. BM-MSC CM and Ad-MSC CM restored these gene expression towards control. They also improved 6 h-I-induced myocardial functional depression, reduced inflammatory cytokine production, decreased apoptosis, and reduced myocardial H2O2. However, neither MSC-exosomes nor exosome-depleted CM recapitulated MSC CM-ameliorated apoptosis and CM-improved mitochondrial preservation during cold ischemia. Knockdown of Per2 by specific siRNA abolished MSC CM-mediated these protective effects in cardiomyocytes following 6 h cold storage. CONCLUSIONS Our results demonstrated that using MSC secretome (BM-MSCs and Ad-MSCs) during prolonged cold storage confers preservation of the normal transcriptional "fingerprint", and reduces donor heart damage. MSC-released soluble factors and exosomes may synergistically act for donor heart protection.
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Affiliation(s)
- Susan R Scott
- Department of Surgery, IU School of Medicine, Indianapolis, IN, U.S.A
| | - Keith L March
- Division of Cardiovascular Medicine, Department of Medicine, IU School of Medicine, Indianapolis, IN, U.S.A,Division of Cardiovascular Medicine, Center for Regenerative Medicine, University of Florida, Gainesville, FL, U.S.A
| | - I-wen Wang
- Department of Surgery, IU School of Medicine, Indianapolis, IN, U.S.A,Methodist Hospital, IU Health, IU School of Medicine, Indianapolis, IN, U.S.A
| | - Kanhaiya Singh
- Department of Surgery, IU School of Medicine, Indianapolis, IN, U.S.A,Indiana Center for Regenerative Medicine and Engineering, Indiana University School of Medicine, Indianapolis, Indiana, U.S.A
| | - Jianyun Liu
- Department of Surgery, IU School of Medicine, Indianapolis, IN, U.S.A
| | - Mark Turrentine
- Department of Surgery, IU School of Medicine, Indianapolis, IN, U.S.A
| | - Chandan K Sen
- Department of Surgery, IU School of Medicine, Indianapolis, IN, U.S.A,Indiana Center for Regenerative Medicine and Engineering, Indiana University School of Medicine, Indianapolis, Indiana, U.S.A
| | - Meijing Wang
- Department of Surgery, IU School of Medicine, Indianapolis, IN, USA.
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Wang M, Scott SR, Koniaris LG, Zimmers TA. Pathological Responses of Cardiac Mitochondria to Burn Trauma. Int J Mol Sci 2020; 21:ijms21186655. [PMID: 32932869 PMCID: PMC7554938 DOI: 10.3390/ijms21186655] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [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] [Subscribe] [Scholar Register] [Received: 07/27/2020] [Revised: 09/04/2020] [Accepted: 09/08/2020] [Indexed: 12/18/2022] Open
Abstract
Despite advances in treatment and care, burn trauma remains the fourth most common type of traumatic injury. Burn-induced cardiac failure is a key factor for patient mortality, especially during the initial post-burn period (the first 24 to 48 h). Mitochondria, among the most important subcellular organelles in cardiomyocytes, are a central player in determining the severity of myocardial damage. Defects in mitochondrial function and structure are involved in pathogenesis of numerous myocardial injuries and cardiovascular diseases. In this article, we comprehensively review the current findings on cardiac mitochondrial pathological changes and summarize burn-impaired mitochondrial respiration capacity and energy supply, induced mitochondrial oxidative stress, and increased cell death. The molecular mechanisms underlying these alterations are discussed, along with the possible influence of other biological variables. We hope this review will provide useful information to explore potential therapeutic approaches that target mitochondria for cardiac protection following burn injury.
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Affiliation(s)
- Meijing Wang
- Department of Surgery, Indiana University School of Medicine, Indianapolis, IN 46202, USA; (S.R.S.); (L.G.K.); (T.A.Z.)
- Correspondence:
| | - Susan R. Scott
- Department of Surgery, Indiana University School of Medicine, Indianapolis, IN 46202, USA; (S.R.S.); (L.G.K.); (T.A.Z.)
| | - Leonidas G. Koniaris
- Department of Surgery, Indiana University School of Medicine, Indianapolis, IN 46202, USA; (S.R.S.); (L.G.K.); (T.A.Z.)
- Simon Cancer Center, Indiana University, Indianapolis, IN 46202, USA
- Indiana Center for Musculoskeletal Health, Indianopolis, IN 46202, USA
- Center for Cachexia Research Innovation and Therapy, Indiana University Purdue University Indianapolis, Indianapolis, IN 46202, USA
| | - Teresa A. Zimmers
- Department of Surgery, Indiana University School of Medicine, Indianapolis, IN 46202, USA; (S.R.S.); (L.G.K.); (T.A.Z.)
- Simon Cancer Center, Indiana University, Indianapolis, IN 46202, USA
- Indiana Center for Musculoskeletal Health, Indianopolis, IN 46202, USA
- Center for Cachexia Research Innovation and Therapy, Indiana University Purdue University Indianapolis, Indianapolis, IN 46202, USA
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Mautner VF, Nguyen R, Kutta H, Fuensterer C, Bokemeyer C, Hagel C, Friedrich RE, Scott SR, Panse J. Bevacizumab induces regression of vestibular schwannomas leading to improved hearing in neurofibromatosis type 2 patients. Akt Neurol 2009. [DOI: 10.1055/s-0029-1238749] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Abstract
Meningiomas account for 18-20% of all intracranial tumours and often recur despite surgical resection. Hydroxyurea is under evaluation as adjuvant therapy of meningiomas. In the authors' initial report of 17 patients with meningioma, hydroxyurea demonstrated modest efficacy, with a median time to progression (TTP) of 80 weeks. In the current study, 21 patients with meningioma have been placed on hydroxyurea (20 mg/kg/day orally), with extended follow-up of the original cohort. Eighteen of 20 evaluable patients (90%) responded with stable disease ranging from 20 to 328 + weeks (median TTP 176 weeks; 11 patients censored). Five of the stabilized patients progressed after 20, 56, 36, 216 and 56 weeks, respectively. Two patients had progressive disease after 10 weeks. Toxicity was mainly haematological. Hydroxyurea has modest activity against meningiomas and should be considered for patients who are poor surgical candidates, have unresectable or large residual meningiomas, or have progressed after surgical resection or irradiation, or both.
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Affiliation(s)
- H B Newton
- Division of Neuro-Oncology, Dardinger Neuro-Oncology Center, Department of Neurology, Ohio State University Medical Center, Columbus, Ohio 43210, USA.
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Scott SR, Reid I, Smith J, Natynczuk S, Robson-Ward M, Vaughan J. A staff perspective of early warning signs intervention for individuals with psychosis: clinical and service implications. J Psychiatr Ment Health Nurs 2004; 11:469-75. [PMID: 15255922 DOI: 10.1111/j.1365-2850.2004.00748.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [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: 11/28/2022]
Abstract
Research has established the benefits of early warnings signs monitoring in the prevention of relapse for individuals with psychosis. This study explored staff views (n = 8) of the implementation of an early warning signs clinic within a day hospital of an adult mental health service. A qualitative methodology using focus groups was adopted and content analysis was used to discover themes arising from the data. Overall, the data indicated a positive view of the early warning signs clinic, with benefits for clients, staff and their relationship; and for service delivery and resources. The clinical and service implications are discussed.
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Affiliation(s)
- S R Scott
- Worcestershire Mental Health Partnership NHS Trust, Mental Health Services, St Anne's Orchard Day Hospital, Malvern, Worcester, UK
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8
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Ulate G, Scott SR, González J, Gilabert JA, Artalejo AR. Extracellular ATP regulates exocytosis in inhibiting multiple Ca(2+) channel types in bovine chromaffin cells. Pflugers Arch 2000; 439:304-14. [PMID: 10650982 DOI: 10.1007/s004249900185] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [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: 10/25/2022]
Abstract
Feedback modulation of voltage-dependent Ca2+ channels by ATP is a well documented phenomenon in bovine chromaffin cells. However, its influence in the control of hormone release is at present poorly understood. By using combined patch-clamp and fura-2 fluorescence measurements we provide evidence that the three Ca2+ channel types (L, N and P/Q) expressed in bovine chromaffin cells are inhibited by ATP (30 microM), and that their involvement in the secretory response, as assayed by capacitance measurements, is roughly proportional to their contribution to the whole-cell Ca2+ current (ICa) both in the absence and presence of ATP. ATP did not modify the capacitance increase observed in cells dialyzed with Ca(2+)-EGTA buffers (1.5 microM free Ca2+), thus excluding a direct effect of ATP on the secretory machinery. Voltage predepolarizations or long chemical (2 s, 70 mM KCl) depolarizations attenuate the effect of ATP on exocytosis by partially relieving the inhibition of ICa Likewise, a strong stimulation that depletes the readily releasable pool of vesicles prevents an inhibitory effect of ATP on the secretory response. While these results lend support to the hypothesis of autocrine modulation of exocytosis by endogenously released ATP acting on P2y-purinoceptors to inhibit ICa, feedback regulation of the rate of release will be a complex function of the occupancy of those receptors and of the electrical and secretory activity of the cell.
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Affiliation(s)
- G Ulate
- Departamento de Farmacología y Terapéutica. Facultad de Medicine, Universidad Autónoma de Madrid, Spain
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Scott SR, Kiessling K, Parekh AB. An examination of the role of intracellular ATP in the activation of store-operated Ca2+ influx and Ca2+-dependent capacitance increases in rat basophilic leukaemia cells. Pflugers Arch 1998; 436:928-33. [PMID: 9799409 DOI: 10.1007/s004240050725] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
The role of ATP in both the activation of store-operated Ca2+ current ICRAC and in Ca2+-dependent vesicular fusion was examined in a study of rat basophilic leukaemia (RBL) cells using the whole-cell patch-clamp technique. Fusion was monitored via changes in plasma membrane capacitance. Following a decrease in the levels of intracellular ATP, achieved using the mitochondrial poison antimycin and the ATP synthase inhibitor oligomycin, as well as a reduction of glycolysis by removal of external glucose, ICRAC activated in a manner similar to control cells when stores are depleted by dialysis with a pipette solution containing either inositol 1,4, 5-trisphosphate (InsP3) or ionomycin together with a high concentration of EGTA. Dialysis of cells for 150 s with the non-hydrolysable ATP analogue 5'-adenylylimidodiphosphate (AMP-PNP) (2 mM) in addition to the mitochondrial inhibitors also failed to prevent activation of ICRAC following external application of ionomycin and thapsigargin, when compared with control recordings obtained with 2 mM ATP instead. Ca2+-dependent vesicular fusion was triggered by dialysing cells with 10 microM Ca2+ and guanosine-5'-O-(3-thiotriphosphate (GTP[gamma-S]). The capacitance increase was unaffected by inhibition of glycolysis, mitochondrial inhibitors or dialysis with either AMP-PNP or adenosine 5'-O-(3-thiotriphosphate) (ATP[gamma-S]) instead of ATP. We conclude that ATP hydrolysis does not seem to be necessary for the activation of ICRAC or for the capacitance increases elicited by high concentrations of intracellular Ca2+.
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Affiliation(s)
- S R Scott
- Laboratory of molecular and cellular signalling, Department of Physiology, University of Oxford, Parks Road, Oxford OX1 3PT, UK
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10
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Abstract
The ontogeny of the cerebral pyruvate recycling pathway and the cellular localization of associated enzymes, malic enzyme (ME) and phosphoenolpyruvate carboxykinase (PEPCK), have been investigated using a combination of 13C NMR spectroscopy, enzymatic analysis, and molecular biology approaches. Activity of the pathway, using [1,2-(13)C2]acetate as a substrate, was detected by 13C NMR in brain extracts 3 weeks after birth, increasing progressively up to the third month of age. In whole-brain homogenates, ME activity increased to adult levels with the same time course as the recycling pathway. PEPCK activity was low during the first 2 weeks of life and decreased further toward adulthood. ME and PEPCK activity were found in primary cultures of astrocytes and in synaptosomal fractions of adult brain. Primary cultures of cortical neurons showed PEPCK activity but no detectable ME activity. The cytosolic ME gene was expressed in primary cultures of neurons and in astrocytes as well as in the neonatal and adult brain. The PEPCK gene was expressed both in primary cultures of cortical neurons and in astrocytes, but the level of its expression in the neonatal and adult brain was undetectable.
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Affiliation(s)
- F Cruz
- Instituto de Investigaciones Biomédicas, CSIC, Madrid, Spain
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Abstract
Preliminary findings are presented regarding Visi-Pitch settings in relation to automatically derived perturbation values (jitter). Jitter values were estimated from sustained phonation of /a/ at each of four filter settings for three subjects using Visi-Pitch. Data were compared to values obtained by hand measuring the same signals and employing Koike's formula. Results indicated that the magnitude of difference between jitter estimated by Visi-Pitch and hand measurement was small. Findings support the use of the manufacturer's recommended filter settings as opposed to alternative settings suggested by Karnell.
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Affiliation(s)
- C K Perry
- Voice and Phonology Research Lab, University of Wyoming, Laramie, USA
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Abstract
This clinical investigation was designed to study the influence of age on stereoselective drug disposition using hexobarbital as a model marker. The disposition of hexobarbital enantiomers was investigated in 10 young and 10 elderly, healthy male volunteers. Mean oral clearance (+/- SD) of d-hexobarbital (1.9 +/- 0.5 vs. 1.7 +/- 0.3 ml/min/kg; P greater than 0.05) did not differ significantly between the young and elderly subjects, respectively. However, despite wide intersubject variability, l-hexobarbital mean oral clearance (+/- SD) was approximately twofold greater in the young than in the elderly subjects (16.9 +/- 11.9 vs. 8.2 +/- 3.2 ml/min/kg; P less than 0.05). This resulted in a significantly greater enantiomeric oral clearance ratio in the young when compared with the elderly subjects (8.3 +/- 3.4 vs. 4.7 +/- 1.4; P less than 0.01). No significant difference (P greater than 0.05) in pharmacologic response after hexobarbital administration was found between the two groups. Demonstration of an age-related preferential decline in metabolism of one enantiomer over another has not been reported previously for any racemic drug in animals or humans.
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Affiliation(s)
- M H Chandler
- Drug Product Evaluation Unit, University of Kentucky College of Pharmacy, Lexington 40536-0082
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13
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Scott SR. Hospital admissions for pneumonia. A Kentucky Peer Review Organization study. J Ky Med Assoc 1985; 83:73-4. [PMID: 3973473] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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Michael RT, Fuchs VR, Scott SR. Changes in the propensity to live alone: 1950-1976. Demography 1980; 17:39-56. [PMID: 7353707] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
The growth in single-person households is a pervasive behavioral phenomenon in the United States in the post-war period. In this paper we investigate determination of the propensity to live alone, using 1970 data across states for single men and women ages 25 to 34 and for elderly widows. Income level appears to be a major determinant of the propensity to live alone. The estimated cross-state equations track about three-quarters of the increase in the propensity to live alone between 1950-1976 and suggest that income growth has been the principal identified influence. Other variables found to affect (positively) the propensity to live alone include mobility, schooling level, and for young people a measure of social climate; non-whites appear to have a somewhat lower propensity to live alone.
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Scott SR. Patient acceptance of the nurse practitioner. Experience in a university health service. J Am Coll Health Assoc 1975; 23:364. [PMID: 1165348] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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16
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Scott SR. The use of problem oriented medical records in college health services. J Am Coll Health Assoc 1974; 22:332-4. [PMID: 4827577] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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Scott SR. A New Method of Demonstrating the Topographical Anatomy of the Adult Human Skull. J Anat Physiol 1906; 40:171-85. [PMID: 17232674 PMCID: PMC1287481] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
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