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Guo Y, Murphy MSQ, Dimanlig-Cruz S, Leclerc A, Smith MA, Corsi DJ, Rennicks White R, Dingwall-Harvey ALJ, Harrold J, Walker MC, Wen SW, El-Chaâr D. Infant Infections Following Cesarean Delivery on Maternal Request: A Population-Based Cohort Study. J Obstet Gynaecol Can 2024; 46:102455. [PMID: 38583665 DOI: 10.1016/j.jogc.2024.102455] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2023] [Revised: 03/05/2024] [Accepted: 03/07/2024] [Indexed: 04/09/2024]
Abstract
OBJECTIVES Investigations about cesarean delivery (CD) on maternal request (CDMR) and infant infection risk frequently rely on administrative data with poorly defined indications for CD. We sought to determine the association between CDMR and infant infection using an intent-to-treat approach. METHODS This was a population-based cohort study of low-risk singleton pregnancies with a term live birth in Ontario, Canada between April 2012 and March 2018. Subjects with prior CD were excluded. Outcomes included upper and lower respiratory tract infections, gastrointestinal infections, otitis media, and a composite of these 4. Relative risk and 95% CI were calculated for component and composite outcomes up to 1 year following planned CDMR versus planned vaginal deliveries (VDs). Subgroup and sensitivity analyses included age at infection (≤28 vs. >28 days), type of care (ambulatory vs. hospitalisation), restricting the cohort to nulliparous pregnancies, and including individuals with previous CD. Last, we re-examined outcome risk on an as-treated basis (actual CD vs. actual VD). RESULTS Of 422 134 pregnancies, 0.4% (1827) resulted in a planned CDMR. After adjusting for covariates, planned CDMR was not associated with a risk of composite infant infections (adjusted relative risk 1.02; 95% CI 0.92-1.11). Findings for component infection outcomes, subgroup, and sensitivity analyses were similar. However, the as-treated analysis of the role of delivery mode on infant risk for infection demonstrated that actual CD (planned and unplanned) was associated with an increased risk for infant infections compared to actual VD. CONCLUSIONS Planned CDMR is not associated with increased risk for neonatal or infant infections compared with planned VD. Study design must be carefully considered when investigating the impact of CDMR on infant infection outcomes.
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Affiliation(s)
- Yanfang Guo
- Better Outcomes Registry and Network (BORN), Ottawa, ON; Clinical Epidemiology Program, Ottawa Hospital Research Institute, Ottawa, ON
| | - Malia S Q Murphy
- Clinical Epidemiology Program, Ottawa Hospital Research Institute, Ottawa, ON
| | - Sheryll Dimanlig-Cruz
- Better Outcomes Registry and Network (BORN), Ottawa, ON; Clinical Epidemiology Program, Ottawa Hospital Research Institute, Ottawa, ON
| | - Alexie Leclerc
- Clinical Epidemiology Program, Ottawa Hospital Research Institute, Ottawa, ON
| | | | - Daniel J Corsi
- Better Outcomes Registry and Network (BORN), Ottawa, ON; Children's Hospital of Eastern Ontario Research Institute, Ottawa, ON
| | - Ruth Rennicks White
- Clinical Epidemiology Program, Ottawa Hospital Research Institute, Ottawa, ON; Department of Obstetrics, Gynecology and Newborn Care, The Ottawa Hospital, Ottawa, ON
| | - Alysha L J Dingwall-Harvey
- Clinical Epidemiology Program, Ottawa Hospital Research Institute, Ottawa, ON; Children's Hospital of Eastern Ontario Research Institute, Ottawa, ON
| | - JoAnn Harrold
- Children's Hospital of Eastern Ontario Research Institute, Ottawa, ON; Department of Obstetrics, Gynecology and Newborn Care, The Ottawa Hospital, Ottawa, ON
| | - Mark C Walker
- Department of Obstetrics and Gynecology, University of Ottawa, Ottawa, ON; International and Global Health Office, University of Ottawa, Ottawa, ON
| | - Shi Wu Wen
- Clinical Epidemiology Program, Ottawa Hospital Research Institute, Ottawa, ON; Department of Obstetrics, Gynecology and Newborn Care, The Ottawa Hospital, Ottawa, ON
| | - Darine El-Chaâr
- Clinical Epidemiology Program, Ottawa Hospital Research Institute, Ottawa, ON; Department of Obstetrics and Gynecology, University of Ottawa, Ottawa, ON.
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Smith MA, Rosenstock CV. Do difficult airway alert cards help if practice doesn't change? Anaesthesia 2022; 77:1077-1080. [PMID: 35949181 DOI: 10.1111/anae.15832] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/20/2022] [Indexed: 11/30/2022]
Affiliation(s)
| | - C V Rosenstock
- Department of Anaesthesia, Nordsjaellands Hospital, Hillerød, Denmark
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Davies-Oliveira JC, Smith MA, Grover S, Canfell K, Crosbie EJ. Eliminating Cervical Cancer: Progress and Challenges for High-income Countries. Clin Oncol (R Coll Radiol) 2021; 33:550-559. [PMID: 34315640 DOI: 10.1016/j.clon.2021.06.013] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2021] [Revised: 06/21/2021] [Accepted: 06/29/2021] [Indexed: 11/26/2022]
Abstract
In 2020, the World Health Organization launched a major initiative to eliminate cervical cancer globally. The initiative is built around the three key pillars of human papillomavirus (HPV) vaccination, cervical screening and treatment, with associated intervention targets for the year 2030. The '90-70-90' targets specify that 90% of adolescent girls receive prophylactic HPV vaccination, 70% of adult women receive a minimum twice-in-a-lifetime cervical HPV test and 90% receive appropriate treatment for preinvasive or invasive disease. Modelling has shown that if these targets are met, the elimination of cervical cancer, defined as fewer than four cases per 100 000 women per annum, will be achieved within a century. Many high-income countries are well positioned to eliminate cervical cancer within the coming decades, but few have achieved '90-70-90' and many challenges must still be addressed to deliver these critical interventions effectively. This review considers the current status of cervical cancer control in relation to each of the three elimination pillars in high-income countries and discusses some of the developments that will assist countries in reaching these ambitious targets by 2030.
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Affiliation(s)
- J C Davies-Oliveira
- Gynaecological Oncology Research Group, Division of Cancer Sciences, University of Manchester, Faculty of Biology, Medicine and Health, Manchester, UK; Department of Obstetrics and Gynaecology, St Mary's Hospital, Manchester University NHS Foundation Trust, Manchester Academic Health Science Centre, Manchester, UK
| | - M A Smith
- The Daffodil Centre, The University of Sydney, a joint venture with Cancer Council NSW, Sydney, New South Wales, Australia
| | - S Grover
- The Daffodil Centre, The University of Sydney, a joint venture with Cancer Council NSW, Sydney, New South Wales, Australia; Department of Radiation Oncology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
| | - K Canfell
- The Daffodil Centre, The University of Sydney, a joint venture with Cancer Council NSW, Sydney, New South Wales, Australia.
| | - E J Crosbie
- Gynaecological Oncology Research Group, Division of Cancer Sciences, University of Manchester, Faculty of Biology, Medicine and Health, Manchester, UK; Department of Obstetrics and Gynaecology, St Mary's Hospital, Manchester University NHS Foundation Trust, Manchester Academic Health Science Centre, Manchester, UK
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Simons ES, Smith MA, Dengler-Crish CM, Crish SD. Retinal ganglion cell loss and gliosis in the retinofugal projection following intravitreal exposure to amyloid-beta. Neurobiol Dis 2021; 147:105146. [PMID: 33122075 DOI: 10.1016/j.nbd.2020.105146] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2020] [Revised: 10/09/2020] [Accepted: 10/23/2020] [Indexed: 01/07/2023] Open
Abstract
Pathological accumulations of amyloid-beta (Aβ) peptide are found in retina early in Alzheimer's disease, yet its effects on retinal neuronal structure remain unknown. To investigate this, we injected fibrillized Aβ1-42 protein into the eye of adult C57BL/6 J mice and analyzed the retina, optic nerve (ON), and the superior colliculus (SC), the primary retinal target in mice. We found that retinal Aβ exposure stimulated microglial activation and retinal ganglion cell (RGC) loss as early as 1-week post-injection. Pathology was not limited to the retina, but propagated into other areas of the central nervous system. Microgliosis spread throughout the retinal projection (retina, ON, and SC), with multiplex protein quantitation demonstrating an increase in endogenously produced Aβ in the ON and SC corresponding to the injected retinas. Surprisingly, this pathology spread to the opposite side, with unilateral Aβ eye injections driving increased Aβ levels, neuroinflammation, and RGC death in the opposite, un-injected retinal projection. As Aβ-mediated microglial activation has been shown to propagate Aβ pathology, we also investigated the role of the Aβ-binding microglial scavenger receptor CD36 in this pathology. Transgenic mice lacking the CD36 receptor were resistant to Aβ-induced inflammation and RGC death up to 2 weeks following exposure. These results indicate that Aβ pathology drives regional neuropathology in the retina and does not remain isolated to the affected eye, but spreads throughout the nervous system. Further, CD36 may serve as a promising target to prevent Aβ-mediated inflammatory damage.
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Affiliation(s)
- E S Simons
- Northeast Ohio Medical University, Rootstown, OH 44272, United States; Kent State Biomedical Sciences Graduate Program, Kent, OH 44240, United States
| | - M A Smith
- Northeast Ohio Medical University, Rootstown, OH 44272, United States; Kent State Biomedical Sciences Graduate Program, Kent, OH 44240, United States; Akron Children's Hospital, Rebecca D. Considine Research Institute, Akron, OH 44302, United States
| | - C M Dengler-Crish
- Northeast Ohio Medical University, Rootstown, OH 44272, United States; Kent State Biomedical Sciences Graduate Program, Kent, OH 44240, United States
| | - S D Crish
- Northeast Ohio Medical University, Rootstown, OH 44272, United States; Kent State Biomedical Sciences Graduate Program, Kent, OH 44240, United States.
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Shishkina EA, Timofeev YS, Volchkova AY, Sharagin PA, Zalyapin VI, Degteva MO, Smith MA, Napier BA. Trabecula: A Random Generator of Computational Phantoms for Bone Marrow Dosimetry. Health Phys 2020; 118:53-59. [PMID: 31764420 DOI: 10.1097/hp.0000000000001127] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
This study was motivated by the efforts to evaluate radiation risk for leukemia incidence in the Techa River cohort, where the main bone marrow dose contributors were Sr (bone-seeking beta emitters). Energy deposition in bone marrow targets was evaluated by simulating radiation particle transport using computational phantoms. The present paper describes the computer program Trabecula implementing an algorithm for parametric generation of computational phantoms, which serve as the basis for calculating bone marrow doses. Trabecula is a user-friendly tool that automatically converts analytical models into voxelized representations that are directly compatible as input to Monte Carlo N Particle code.
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Affiliation(s)
| | - Y S Timofeev
- Urals Research Centre for Radiation Medicine (URCRM), Chelyabinsk, Russia
| | - A Y Volchkova
- Urals Research Centre for Radiation Medicine (URCRM), Chelyabinsk, Russia
| | - P A Sharagin
- Urals Research Centre for Radiation Medicine (URCRM), Chelyabinsk, Russia
| | - V I Zalyapin
- Southern Urals State University (SUSU), Chelyabinsk, Russia
| | - M O Degteva
- Urals Research Centre for Radiation Medicine (URCRM), Chelyabinsk, Russia
| | - M A Smith
- Pacific Northwest National Laboratory, Richland, WA
| | - B A Napier
- Pacific Northwest National Laboratory, Richland, WA
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Degteva MO, Napier BA, Tolstykh EI, Shishkina EA, Shagina NB, Volchkova AY, Bougrov NG, Smith MA, Anspaugh LR. Enhancements in the Techa River Dosimetry System: TRDS-2016D Code for Reconstruction of Deterministic Estimates of Dose From Environmental Exposures. Health Phys 2019; 117:378-387. [PMID: 30958804 DOI: 10.1097/hp.0000000000001067] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Waterborne releases to the Techa River from the Mayak plutonium facility in Russia during 1949-1956 resulted in significant doses to persons living downstream. The dosimetry system Techa River Dosimetry System-2016D has been developed, which provides individual doses of external and internal exposure for the members of the Techa River cohort and other persons who were exposed to releases of radioactive material to the Southern Urals. The results of computation of individual doses absorbed in red bone marrow and extraskeletal tissues for the Techa River cohort members (29,647 persons) are presented, which are based on residence histories on the contaminated Techa River and the East Urals Radioactive Trace, which was formed in 1957 as a result of the Kyshtym Accident. Available Sr body-burden measurements and available information on individual household locations have been used for refinement of individual dose estimates. Techa River Dosimetry System-2016D-based dose estimates will be used for verification of risk of low-dose-rate effects of ionizing radiation in the Techa River cohort.
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Affiliation(s)
- M O Degteva
- Urals Research Center for Radiation Medicine, Chelyabinsk, Russia
| | - B A Napier
- Battelle Pacific Northwest National Laboratory, Richland, WA
| | - E I Tolstykh
- Urals Research Center for Radiation Medicine, Chelyabinsk, Russia
| | - E A Shishkina
- Urals Research Center for Radiation Medicine, Chelyabinsk, Russia
| | - N B Shagina
- Urals Research Center for Radiation Medicine, Chelyabinsk, Russia
| | - A Yu Volchkova
- Urals Research Center for Radiation Medicine, Chelyabinsk, Russia
| | - N G Bougrov
- Urals Research Center for Radiation Medicine, Chelyabinsk, Russia
| | - M A Smith
- Battelle Pacific Northwest National Laboratory, Richland, WA
| | - L R Anspaugh
- Emeritus, Department of Radiology, University of Utah, Salt Lake City, UT
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Abstract
OBJECTIVES To examine whether there are associations between active travel and markers of a healthy, low-carbon (HLC) diet (increased consumption of fruit and vegetables (FV), reduced consumption of red and processed meat (RPM)). DESIGN Cross-sectional analysis of a cohort study. SETTINGS Population cohort of over 500 000 people recruited from 22 centres across the UK. Participants aged between 40 and 69 years were recruited between 2006 and 2010. PARTICIPANTS 412 299 adults with complete data on travel mode use, consumption of FV and RPM, and sociodemographic covariates were included in the analysis. EXPOSURE MEASURES Mutually exclusive mode or mode combinations of travel (car, public transport, walking, cycling) for non-work and commuting journeys. OUTCOME MEASURES Consumption of FV measured as portions per day and RPM measured as frequency per week. RESULTS Engaging in all types of active travel was positively associated with higher FV consumption and negatively associated with more frequent RPM consumption. Cycling exclusively or in combination with walking was most strongly associated with increased dietary consumption of FV and reduced consumption of RPM for both non-work and commuting journeys. Overall, the strongest associations were between non-work cycling and FV consumption (males: adjusted OR=2.18, 95% CI 2.06 to 2.30; females: adjusted OR=2.50, 95% CI 2.31 to 2.71) and non-work cycling and RPM consumption (males: adjusted OR=0.57, 95% CI 0.54 to 0.60; females: adjusted OR=0.54, 95% CI 0.50 to 0.59). Associations were generally similar for both commuting and non-work travel, and were robust to adjustment with sociodemographic and behavioural factors. CONCLUSIONS There are strong associations between engaging in active travel, particularly cycling, and HLC dietary consumption, suggesting that these HLC behaviours are related. Further research is needed to better understand the drivers and dynamics between these behaviours within individuals, and whether they share common underlying causes.
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Affiliation(s)
| | - Jan Rasmus Boehnke
- Department of Health Sciences, University of York, York, UK
- School of Nursing and Health Sciences, University of Dundee, Dundee, UK
| | - Hilary Graham
- Department of Health Sciences, University of York, York, UK
| | - Piran C L White
- Department of Environment and Geography, University of York, York, UK
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Hudspeth K, Wang S, Wang J, Rahman S, Smith MA, Casey KA, Manna Z, Sanjuan M, Kolbeck R, Hasni S, Ettinger R, Siegel RM. Natural killer cell expression of Ki67 is associated with elevated serum IL-15, disease activity and nephritis in systemic lupus erythematosus. Clin Exp Immunol 2019; 196:226-236. [PMID: 30693467 DOI: 10.1111/cei.13263] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/13/2018] [Indexed: 12/13/2022] Open
Abstract
Systemic lupus erythematosus (SLE) is a complex autoimmune disorder whose pathology involves multiple immune cell types, including B and T lymphocytes as well as myeloid cells. While it is clear that autoantibody-producing B cells, as well as CD4+ T cell help, are key contributors to disease, little is known regarding the role of innate lymphoid cells such as natural killer (NK) cells in the pathogenesis of SLE. We have characterized the phenotype of NK cells by multi-color flow cytometry in a large cohort of SLE patients. While the overall percentage of NK cells was similar or slightly decreased compared to healthy controls, a subset of patients displayed a high frequency of NK cells expressing the proliferation marker, Ki67, which was not found in healthy donors. Although expression of Ki67 on NK cells correlated with Ki67 on other immune cell subsets, the frequency of Ki67 on NK cells was considerably higher. Increased frequencies of Ki67+ NK cells correlated strongly with clinical severity and active nephritis and was also related to low NK cell numbers, but not overall leukopenia. Proteomic and functional data indicate that the cytokine interleukin-15 promotes the induction of Ki67 on NK cells. These results suggest a role for NK cells in regulating the immune-mediated pathology of SLE as well as reveal a possible target for therapeutic intervention.
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Affiliation(s)
- K Hudspeth
- Immunoregulation Section, Autoimmunity Branch, National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS), National Institutes of Health, Bethesda, MD, USA
| | - S Wang
- Respiratory, Inflammation, and Autoimmunity Group, MedImmune LLC, Gaithersburg, MD, USA
| | - J Wang
- Respiratory, Inflammation, and Autoimmunity Group, MedImmune LLC, Gaithersburg, MD, USA
| | - S Rahman
- Respiratory, Inflammation, and Autoimmunity Group, MedImmune LLC, Gaithersburg, MD, USA
| | - M A Smith
- Respiratory, Inflammation, and Autoimmunity Group, MedImmune LLC, Gaithersburg, MD, USA
| | - K A Casey
- Respiratory, Inflammation, and Autoimmunity Group, MedImmune LLC, Gaithersburg, MD, USA
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- Respiratory, Inflammation, and Autoimmunity Group, MedImmune LLC, Gaithersburg, MD, USA
| | - Z Manna
- Office of the Clinical Director, National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS), National Institutes of Health, Bethesda, Maryland, USA
| | - M Sanjuan
- Respiratory, Inflammation, and Autoimmunity Group, MedImmune LLC, Gaithersburg, MD, USA
| | - R Kolbeck
- Respiratory, Inflammation, and Autoimmunity Group, MedImmune LLC, Gaithersburg, MD, USA
| | - S Hasni
- Office of the Clinical Director, National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS), National Institutes of Health, Bethesda, Maryland, USA
| | - R Ettinger
- Respiratory, Inflammation, and Autoimmunity Group, MedImmune LLC, Gaithersburg, MD, USA
| | - R M Siegel
- Immunoregulation Section, Autoimmunity Branch, National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS), National Institutes of Health, Bethesda, MD, USA.,Office of the Clinical Director, National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS), National Institutes of Health, Bethesda, Maryland, USA
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Angelopoulos NV, Harvey JP, Bolland JD, Nunn AD, Noble RAA, Smith MA, Taylor MJ, Masters JEG, Moxon J, Cowx IG. Overcoming the dichotomy of implementing societal flood risk management while conserving instream fish habitat - A long-term study from a highly modified urban river. J Environ Manage 2018; 224:69-76. [PMID: 30031920 DOI: 10.1016/j.jenvman.2018.07.030] [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] [Subscribe] [Scholar Register] [Received: 05/18/2018] [Revised: 07/10/2018] [Accepted: 07/10/2018] [Indexed: 06/08/2023]
Abstract
Flood Risk Management (FRM) is often essential to reduce the risk of flooding to properties and infrastructure in urban landscapes, but typically degrades the habitats required by many aquatic animals for foraging, refuge and reproduction. This conflict between flood risk management and biodiversity is driven by conflicting directives, such as the EU Floods and Water Framework Directives, and has led to a requirement for synergistic solutions for FRM that integrate river restoration actions. Unfortunately, ecological monitoring and appraisal of combined FRM and river restoration works is inadequate. This paper uses a case study from the River Don in Northern England to evaluate the effects of the FRM and subsequent river restoration works on instream habitat and the associated fish assemblage over an 8-year period. Flood risk management created a homogeneous channel but did not negatively affect fish species composition or densities, specifically brown trout. Densities of adult brown trout were comparable pre and post-FRM, while densities of juvenile bullhead and brown trout increased dramatically post FRM. River restoration works created a heterogeneous channel but did not significantly improve species composition or brown trout density. Species composition post-river restoration works returned to that similar to pre-FRM over a short-term period, but with improved numbers of juvenile bullhead. Although habitat complexity increased after river restoration works, long-term changes in species composition and densities were marginal, probably because the river reset habitat complexity within the time framework of the study.
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Affiliation(s)
- N V Angelopoulos
- Hull International Fisheries Institute, School of Environmental Sciences, University of Hull, Hull HU6 7RX, UK.
| | - J P Harvey
- Hull International Fisheries Institute, School of Environmental Sciences, University of Hull, Hull HU6 7RX, UK
| | - J D Bolland
- Hull International Fisheries Institute, School of Environmental Sciences, University of Hull, Hull HU6 7RX, UK
| | - A D Nunn
- Hull International Fisheries Institute, School of Environmental Sciences, University of Hull, Hull HU6 7RX, UK
| | - R A A Noble
- Hull International Fisheries Institute, School of Environmental Sciences, University of Hull, Hull HU6 7RX, UK
| | - M A Smith
- Hull International Fisheries Institute, School of Environmental Sciences, University of Hull, Hull HU6 7RX, UK
| | - M J Taylor
- Hull International Fisheries Institute, School of Environmental Sciences, University of Hull, Hull HU6 7RX, UK
| | - J E G Masters
- Environment Agency, Fisheries, Biodiversity and Geomorphology, Yorkshire Area. Lateral, 8 City Walk. Leeds LS11 9AT, UK
| | - J Moxon
- Environment Agency, Fisheries, Biodiversity and Geomorphology, Yorkshire Area. Lateral, 8 City Walk. Leeds LS11 9AT, UK
| | - I G Cowx
- Hull International Fisheries Institute, School of Environmental Sciences, University of Hull, Hull HU6 7RX, UK
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Smith MA, Plyler ES, Dengler-Crish CM, Meier J, Crish SD. Nodes of Ranvier in Glaucoma. Neuroscience 2018; 390:104-118. [PMID: 30149050 DOI: 10.1016/j.neuroscience.2018.08.016] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2018] [Revised: 08/15/2018] [Accepted: 08/17/2018] [Indexed: 01/13/2023]
Abstract
Retinal ganglion cell axons of the DBA/2J mouse model of glaucoma, a model characterized by extensive neuroinflammation, preserve synaptic contacts with their subcortical targets for a time after onset of anterograde axonal transport deficits, axon terminal hypertrophy, and cytoskeletal alterations. Though retrograde axonal transport is still evident in these axons, it is unknown if they retain their ability to transmit visual information to the brain. Using a combination of in vivo multiunit electrophysiology, neuronal tract tracing, multichannel immunofluorescence, and transmission electron microscopy, we report that eye-brain signaling deficits precede transport loss and axonal degeneration in the DBA/2J retinal projection. These deficits are accompanied by node of Ranvier pathology - consisting of increased node length and redistribution of the voltage-gated sodium channel Nav1.6 that parallel changes seen early in multiple sclerosis (MS) axonopathy. Further, with age, axon caliber and neurofilament density increase without corresponding changes in myelin thickness. In contrast to these findings in DBA/2J mice, node pathologies were not observed in the induced microbead occlusion model of glaucoma - a model that lacks pre-existing inflammation. After one week of systemic treatment with fingolimod, an immunosuppressant therapy for relapsing-remitting MS, DBA/2J mice showed a substantial reduction in node pathology and mild effects on axon morphology. These data suggest that neurophysiological deficits in the DBA/2J may be due to defects in intact axons and targeting node pathology may be a promising intervention for some types of glaucoma.
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Affiliation(s)
- M A Smith
- Northeast Ohio Medical University, Rootstown, OH 44272, United States
| | - E S Plyler
- Northeast Ohio Medical University, Rootstown, OH 44272, United States; Kent State Biomedical Sciences Graduate Program, United States
| | - C M Dengler-Crish
- Northeast Ohio Medical University, Rootstown, OH 44272, United States
| | - J Meier
- Northeast Ohio Medical University, Rootstown, OH 44272, United States
| | - S D Crish
- Northeast Ohio Medical University, Rootstown, OH 44272, United States.
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Abstract
Autologous blood transfusion is one of the most effective ways of avoiding the need for homologous transfusion and all its associated complications. Since the beginning of 1985, autotransfusions have been used in 48 patients undergoing total joint replacement, without significant complications. Their average haemoglobin level two weeks postoperatively was 11.3 mg/dl. We believe that this is a safe, effective and economical procedure which benefits both patients and medical staff, and its use should be more widespread.
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Henderson LE, Abdelmegeed MA, Yoo SH, Rhee SG, Zhu X, Smith MA, Nguyen RQ, Perry G, Song BJ. Enhanced Phosphorylation of Bax and Its Translocation into Mitochondria in the Brains of Individuals Affiliated with Alzheimer's Disease. Open Neurol J 2017; 11:48-58. [PMID: 29290835 PMCID: PMC5738752 DOI: 10.2174/1874205x01711010048] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2017] [Revised: 09/05/2017] [Accepted: 10/10/2017] [Indexed: 12/22/2022] Open
Abstract
Background: Despite increased neuronal death, senile plaques, and neurofibrillary tangles observed in patients suffering from Alzheimer’s disease (AD), the detailed mechanism of cell death in AD is still poorly understood. Method: We hypothesized that p38 kinase activates and then phosphorylates Bax, leading to its translocation to mitochondria in AD brains compared to controls. The aim of this study was to investigate the role of p38 kinase in phosphorylation and sub-cellular localization of pro-apoptotic Bax in the frontal cortex of the brains from AD and control subjects. Increased oxidative stress in AD individuals compared to control was evaluated by measuring the levels of carbonylated proteins and oxidized peroxiredoxin, an antioxidant enzyme. The relative amounts of p38 kinase and phospho-Bax in mitochondria in AD brains and controls were determined by immunoblot analysis using the respective antibody against each protein following immunoprecipitation. Results: Our results showed that the levels of oxidized peroxiredoxin-SO3 and carbonylated proteins are significantly elevated in AD brains compared to controls, demonstrating the increased oxidative stress. Conclusion: The amount of phospho-p38 kinase is increased in AD brains and the activated p38 kinase appears to phosphorylate Thr residue(s) of Bax, which leads to its mitochondrial translocation, contributing to apoptosis and ultimately, neurodegeneration.
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Affiliation(s)
- L E Henderson
- Laboratory of Membrane Biochemistry and Biophysics, National Institute on Alcohol Abuse and Alcoholism, Bethesda, Maryland 20892-9410, USA
| | - M A Abdelmegeed
- Laboratory of Membrane Biochemistry and Biophysics, National Institute on Alcohol Abuse and Alcoholism, Bethesda, Maryland 20892-9410, USA
| | - S H Yoo
- Laboratory of Membrane Biochemistry and Biophysics, National Institute on Alcohol Abuse and Alcoholism, Bethesda, Maryland 20892-9410, USA
| | - S G Rhee
- Division of Life and Pharmaceutical Sciences, Ewha Womans University, Seoul, Korea
| | - X Zhu
- Department of Pathology, Case Western Reserve University, Cleveland, Ohio 44106, USA
| | - M A Smith
- Department of Pathology, Case Western Reserve University, Cleveland, Ohio 44106, USA
| | - R Q Nguyen
- Department of Biology, College of Sciences, University of Texas at San Antonio, San Antonio, TX, USA
| | - G Perry
- Department of Biology, College of Sciences, University of Texas at San Antonio, San Antonio, TX, USA
| | - B J Song
- Laboratory of Membrane Biochemistry and Biophysics, National Institute on Alcohol Abuse and Alcoholism, Bethesda, Maryland 20892-9410, USA
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Konecky RO, Smith MA, Olson CR. Monkey prefrontal neurons during Sternberg task performance: full contents of working memory or most recent item? J Neurophysiol 2017; 117:2269-2281. [PMID: 28331006 DOI: 10.1152/jn.00541.2016] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2016] [Revised: 02/16/2017] [Accepted: 03/08/2017] [Indexed: 11/22/2022] Open
Abstract
To explore the brain mechanisms underlying multi-item working memory, we monitored the activity of neurons in the dorsolateral prefrontal cortex while macaque monkeys performed spatial and chromatic versions of a Sternberg working-memory task. Each trial required holding three sequentially presented samples in working memory so as to identify a subsequent probe matching one of them. The monkeys were able to recall all three samples at levels well above chance, exhibiting modest load and recency effects. Prefrontal neurons signaled the identity of each sample during the delay period immediately following its presentation. However, as each new sample was presented, the representation of antecedent samples became weak and shifted to an anomalous code. A linear classifier operating on the basis of population activity during the final delay period was able to perform at approximately the level of the monkeys on trials requiring recall of the third sample but showed a falloff in performance on trials requiring recall of the first or second sample much steeper than observed in the monkeys. We conclude that delay-period activity in the prefrontal cortex robustly represented only the most recent item. The monkeys apparently based performance of this classic working-memory task on some storage mechanism in addition to the prefrontal delay-period firing rate. Possibilities include delay-period activity in areas outside the prefrontal cortex and changes within the prefrontal cortex not manifest at the level of the firing rate.NEW & NOTEWORTHY It has long been thought that items held in working memory are encoded by delay-period activity in the dorsolateral prefrontal cortex. Here we describe evidence contrary to that view. In monkeys performing a serial multi-item working memory task, dorsolateral prefrontal neurons encode almost exclusively the identity of the sample presented most recently. Information about earlier samples must be encoded outside the prefrontal cortex or represented within the prefrontal cortex in a cryptic code.
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Affiliation(s)
- R O Konecky
- Department of Neuroscience, University of Pittsburgh, Pittsburgh, Pennsylvania.,Center for the Neural Basis of Cognition, Carnegie Mellon University, Pittsburgh, Pennsylvania; and.,Departments of Ophthalmology and Bioengineering, and Fox Center for Vision Restoration, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - M A Smith
- Department of Neuroscience, University of Pittsburgh, Pittsburgh, Pennsylvania.,Center for the Neural Basis of Cognition, Carnegie Mellon University, Pittsburgh, Pennsylvania; and.,Departments of Ophthalmology and Bioengineering, and Fox Center for Vision Restoration, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - C R Olson
- Department of Neuroscience, University of Pittsburgh, Pittsburgh, Pennsylvania; .,Center for the Neural Basis of Cognition, Carnegie Mellon University, Pittsburgh, Pennsylvania; and
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Tran H, Grimm J, Wang B, Smith MA, Gogola A, Nelson S, Tyler-Kabara E, Schuman J, Wollstein G, Sigal IA. Mapping in-vivo optic nerve head strains caused by intraocular and intracranial pressures. Proc SPIE Int Soc Opt Eng 2017; 10067. [PMID: 29618852 DOI: 10.1117/12.2257360] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Although it is well documented that abnormal levels of either intraocular (IOP) or intracranial pressure (ICP) can lead to potentially blinding conditions, such as glaucoma and papilledema, little is known about how the pressures actually affect the eye. Even less is known about potential interplay between their effects, namely how the level of one pressure might alter the effects of the other. Our goal was to measure in-vivo the pressure-induced stretch and compression of the lamina cribrosa due to acute changes of IOP and ICP. The lamina cribrosa is a structure within the optic nerve head, in the back of the eye. It is important because it is in the lamina cribrosa that the pressure-induced deformations are believed to initiate damage to neural tissues leading to blindness. An eye of a rhesus macaque monkey was imaged in-vivo with optical coherence tomography while IOP and ICP were controlled through cannulas in the anterior chamber and lateral ventricle, respectively. The image volumes were analyzed with a newly developed digital image correlation technique. The effects of both pressures were highly localized, nonlinear and non-monotonic, with strong interactions. Pressure variations from the baseline normal levels caused substantial stretch and compression of the neural tissues in the posterior pole, sometimes exceeding 20%. Chronic exposure to such high levels of biomechanical insult would likely lead to neural tissue damage and loss of vision. Our results demonstrate the power of digital image correlation technique based on non-invasive imaging technologies to help understand how pressures induce biomechanical insults and lead to vision problems.
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Affiliation(s)
- H Tran
- Department of Ophthalmology, University of Pittsburgh, 203 Lothrop St., Pittsburgh, PA, USA 15213.,Department of Bioengineering, University of Pittsburgh, 3700 O'Hara St., Pittsburgh, PA, USA 15213
| | - J Grimm
- Department of Ophthalmology, University of Pittsburgh, 203 Lothrop St., Pittsburgh, PA, USA 15213
| | - B Wang
- Department of Ophthalmology, University of Pittsburgh, 203 Lothrop St., Pittsburgh, PA, USA 15213.,Department of Bioengineering, University of Pittsburgh, 3700 O'Hara St., Pittsburgh, PA, USA 15213
| | - M A Smith
- Department of Ophthalmology, University of Pittsburgh, 203 Lothrop St., Pittsburgh, PA, USA 15213.,Department of Bioengineering, University of Pittsburgh, 3700 O'Hara St., Pittsburgh, PA, USA 15213
| | - A Gogola
- Department of Ophthalmology, University of Pittsburgh, 203 Lothrop St., Pittsburgh, PA, USA 15213
| | - S Nelson
- Department of Ophthalmology, University of Pittsburgh, 203 Lothrop St., Pittsburgh, PA, USA 15213
| | - E Tyler-Kabara
- Department of Neurosurgery, University of Pittsburgh, 200 Lothrop St, Pittsburgh PA, USA 15213
| | - J Schuman
- NYU Langone Eye Center, NYU School of Medicine, 240 East 38 St., New York, NY, USA 10016
| | - G Wollstein
- NYU Langone Eye Center, NYU School of Medicine, 240 East 38 St., New York, NY, USA 10016
| | - I A Sigal
- Department of Ophthalmology, University of Pittsburgh, 203 Lothrop St., Pittsburgh, PA, USA 15213.,Department of Bioengineering, University of Pittsburgh, 3700 O'Hara St., Pittsburgh, PA, USA 15213
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15
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Ruesch A, Smith MA, Wollstein G, Sigal IA, Nelson S, Kainerstorfer JM. Correlation between Cerebral Hemodynamic and Perfusion Pressure Changes in Non-Human Primates. Proc SPIE Int Soc Opt Eng 2017; 10059:100591P. [PMID: 29311754 PMCID: PMC5755600 DOI: 10.1117/12.2252550] [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] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
The mechanism that maintains a stable blood flow in the brain despite changes in cerebral perfusion pressure (CPP), and therefore guaranties a constant supply of oxygen and nutrients to the neurons, is known as cerebral autoregulation (CA). In a certain range of CPP, blood flow is mediated by a vasomotor adjustment in vascular resistance through dilation of blood vessels. CA is known to be impaired in diseases like traumatic brain injury, Parkinson's disease, stroke, hydrocephalus and others. If CA is impaired, blood flow and pressure changes are coupled and the oxygen supply might be unstable. Lassen's blood flow autoregulation curve describes this mechanism, where a plateau of stable blood flow in a specific range of CPP corresponds to intact autoregulation. Knowing the limits of this plateau and maintaining CPP within these limits can improve patient outcome. Since CPP is influenced by both intracranial pressure and arterial blood pressure, long term changes in either can lead to autoregulation impairment. Non-invasive methods for monitoring blood flow autoregulation are therefore needed. We propose to use Near infrared spectroscopy (NIRS) to fill this need. NIRS is an optical technique, which measures microvascular changes in cerebral hemoglobin concentration. We pe erformed experiments on non-human primates during exsanguination to demonstrate that the limits of blood flow autoregulation can be accessed with NIRS.
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Affiliation(s)
- A Ruesch
- Department of Biomedical Engineering, Carnegie Mellon University, 5000 Forbes Avenue, Pittsburgh, PA 15213
| | - M A Smith
- Department of Ophthalmology, University of Pittsburgh, Eye and Ear Institute, 203 Lothrop Street, Pittsburgh, PA 15213
| | - G Wollstein
- NYU Langone Eye Center, New York University School of Medicine, 462 First Avenue, New York, NY 10016
| | - I A Sigal
- Department of Ophthalmology, University of Pittsburgh, Eye and Ear Institute, 203 Lothrop Street, Pittsburgh, PA 15213
| | - S Nelson
- Department of Ophthalmology, University of Pittsburgh, Eye and Ear Institute, 203 Lothrop Street, Pittsburgh, PA 15213
| | - J M Kainerstorfer
- Department of Biomedical Engineering, Carnegie Mellon University, 5000 Forbes Avenue, Pittsburgh, PA 15213
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16
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Sellers RM, Smith MA, Shelton JN, Rowley SA, Chavous TM. Multidimensional Model of Racial Identity: A Reconceptualization of African American Racial Identity. Pers Soc Psychol Rev 2016; 2:18-39. [PMID: 15647149 DOI: 10.1207/s15327957pspr0201_2] [Citation(s) in RCA: 570] [Impact Index Per Article: 71.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
Abstract
Research on African American racial identity has utilized 2 distinct approaches. The mainstream approach has focused on universal properties associated with ethnic and racial identities. In contrast, the underground approach has focused on documenting the qualitative meaning of being African American, with an emphasis on the unique cultural and historical experiences of African Americans. The Multidimensional Model of Racial Identity (MMRI) represents a synthesis of the strengths of these two approaches. The underlying assumptions associated with the model are explored. The model proposes 4 dimensions of African American racial identity: salience, centrality, regard, and ideology. A description of these dimensions is provided along with a discussion of how they interact to influence behavior at the level of the event. We argue that the MMRI has the potential to make contributions to traditional research objectives of both approaches, as well as to provide the impetus to explore new questions.
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Affiliation(s)
- R M Sellers
- Department of Psychology, University of Michigan, Ann Arbor, USA.
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17
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Smith MA, Bush RD, van de Ven RJ, Hopkins DL. The combined effects of grain supplementation and tenderstretching on alpaca (Vicugna pacos) meat quality. Meat Sci 2016; 125:53-60. [PMID: 27888773 DOI: 10.1016/j.meatsci.2016.11.015] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2016] [Revised: 11/18/2016] [Accepted: 11/20/2016] [Indexed: 11/24/2022]
Abstract
This study investigated the effects of feeding a mixed grain supplement and tenderstretching (TS) alpaca carcasses on meat quality. A total of 56 castrated 24month old alpacas were divided into two treatments (pasture-only, and pasture plus supplementation). Supplemented groups were fed a mixed grain ration in addition to ad lib pasture for 10weeks. Animals were slaughtered across two kill days (n=28). One half of each carcass was suspended by the pelvis (TS) prior to chilling, and the other half was Achilles tendon hung (AH). After 24h, muscles were removed and aged for 10 and 25d. TS significantly increased sarcomere length and reduced shear force and cooking loss in the m. semimembranosus. This trend was not observed in other muscles including the m. longissimus thoracis et lumborum (LL) and m. psoas major. Ageing period resulted in a marginal improvement in LL tenderness. There is clear evidence that TS improves tenderness in the hindquarter of alpacas.
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Affiliation(s)
- M A Smith
- The University of Sydney, Faculty of Veterinary Science, 425 Werombi Road, Camden, NSW 2570, Australia.
| | - R D Bush
- The University of Sydney, Faculty of Veterinary Science, 425 Werombi Road, Camden, NSW 2570, Australia
| | - R J van de Ven
- NSW Department of Primary Industries, Orange Agricultural Institute, Forest Road, Orange, NSW 2800, Australia
| | - D L Hopkins
- NSW Department of Primary Industries, Centre for Red Meat and Sheep Development, Cowra, NSW 2794, Australia
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18
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Smith MA, Böhnke JR, Graham H, White PCL, Prady SL. OP24 Associations between active travel and diet: An exploration of pro-health, low carbon behaviours in the National Diet and Nutrition Survey. Br J Soc Med 2016. [DOI: 10.1136/jech-2016-208064.24] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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19
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Jones L, Carol H, Evans K, Richmond J, Houghton PJ, Smith MA, Lock RB. A review of new agents evaluated against pediatric acute lymphoblastic leukemia by the Pediatric Preclinical Testing Program. Leukemia 2016; 30:2133-2141. [PMID: 27416986 DOI: 10.1038/leu.2016.192] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2016] [Revised: 05/31/2016] [Accepted: 07/04/2016] [Indexed: 02/07/2023]
Abstract
Acute lymphoblastic leukemia (ALL) in children exemplifies how multi-agent chemotherapy has improved the outcome for patients. Refinements in treatment protocols and improvements in supportive care for this most common pediatric malignancy have led to a cure rate that now approaches 90%. However, certain pediatric ALL subgroups remain relatively intractable to treatment and many patients who relapse face a similarly dismal outcome. Moreover, survivors of pediatric ALL suffer the long-term sequelae of their intensive treatment throughout their lives. Therefore, the development of drugs to treat relapsed/refractory pediatric ALL, as well as those that more specifically target leukemia cells, remains a high priority. As pediatric malignancies represent a minority of the overall cancer burden, it is not surprising that they are generally underrepresented in drug development efforts. The identification of novel therapies relies largely on the reappropriation of drugs developed for adult malignancies. However, despite the large number of experimental agents available, clinical evaluation of novel drugs for pediatric ALL is hindered by limited patient numbers and the availability of effective established drugs. The Pediatric Preclinical Testing Program (PPTP) was established in 2005 to provide a mechanism by which novel therapeutics could be evaluated against xenograft and cell line models of the most common childhood malignancies, including ALL, to prioritize those with the greatest activity for clinical evaluation. In this article, we review the results of >50 novel agents and combinations tested against the PPTP ALL xenografts, highlighting comparisons between PPTP results and clinical data where possible.
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Affiliation(s)
- L Jones
- Leukaemia Biology Program, Children's Cancer Institute, Lowy Cancer Research Centre, UNSW, Sydney, New South Wales, Australia
| | - H Carol
- Leukaemia Biology Program, Children's Cancer Institute, Lowy Cancer Research Centre, UNSW, Sydney, New South Wales, Australia
| | - K Evans
- Leukaemia Biology Program, Children's Cancer Institute, Lowy Cancer Research Centre, UNSW, Sydney, New South Wales, Australia
| | - J Richmond
- Leukaemia Biology Program, Children's Cancer Institute, Lowy Cancer Research Centre, UNSW, Sydney, New South Wales, Australia
| | - P J Houghton
- Molecular Medicine, Greehey Children's Cancer Research Institute, University of Texas Health Science Center at San Antonio, San Antonio, TX, USA
| | - M A Smith
- Cancer Therapy Evaluation Program, NCI, Bethesda, MD, USA
| | - R B Lock
- Leukaemia Biology Program, Children's Cancer Institute, Lowy Cancer Research Centre, UNSW, Sydney, New South Wales, Australia
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20
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Affiliation(s)
- M A Smith
- University of Newcastle-upon-Tyne, Newcastle-upon-Tyne, UK.
| | - A J Byrne
- Institute of Medical Education, College of Biomedical and Life Sciences, Cardiff University School of Medicine, Cardiff, UK
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21
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Yoshida T, Zhang G, Smith MA, Lopez AS, Bai Y, Li J. Correction: Tyrosine Phosphoproteomics Identifies Both Codrivers and Cotargeting Strategies for T790M-Related EGFR-TKI Resistance in Non-Small Cell Lung Cancer. Clin Cancer Res 2015; 21:3571. [PMID: 26240294 DOI: 10.1158/1078-0432.ccr-15-1183] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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22
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Joseph L, Casanegra AI, Dhariwal M, Smith MA, Raju MG, Militello MA, Gomes MP, Gornik HL, Bartholomew JR. Bivalirudin for the treatment of patients with confirmed or suspected heparin-induced thrombocytopenia. J Thromb Haemost 2014; 12:1044-53. [PMID: 24766902 DOI: 10.1111/jth.12592] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [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] [Received: 12/06/2014] [Accepted: 04/14/2014] [Indexed: 02/04/2023]
Abstract
BACKGROUND Heparin-induced thrombocytopenia (HIT) is an adverse immune-mediated response to unfractionated heparin and, less commonly, low molecular weight heparin. It is associated with a high thrombotic risk and the potential for limb and life-threatening complications. Argatroban is the only approved and currently available anticoagulant for HIT treatment in the USA. OBJECTIVES To report safety and efficacy outcomes with bivalirudin for HIT treatment. METHODS We retrospectively examined records from our registry of patients with a suspected, confirmed or previous history of HIT and who had received bivalirudin for anticoagulation in a single tertiary-care center over a 9-year period. RESULTS We identified 461 patients who received bivalirudin: 220 (47.7%) were surgical patients, and 241 (52.3%) were medical patients. Of this population, 107 (23.2%) were critically ill, and 109 (23.6%) were dialysis-dependent. Suspected, confirmed and previous history of HIT were reported in 262, 124 and 75 patients, respectively. Of 386 patients with suspected or confirmed HIT, 223 patients (57.8%) had thrombosis at HIT diagnosis. New thrombosis was identified in 21 patients (4.6%) while they were on treatment with therapeutic doses of bivalirudin. No patient required HIT-related amputation. Major bleeding occurred in 35 patients (7.6%). We found a significant increase in major bleeding risk in the critically ill population (13.1%; odds ratio 2.4, 95% confidence interval 1.2-4.9, P = 0.014). The 30-day all-cause mortality rate was 14.5% (67 patients), and eight of 67 (1.7%) deaths were HIT-related. CONCLUSION Bivalirudin may be an effective and safe alternative option for the treatment of both suspected and confirmed HIT, and appears to reduce the rate of HIT-related amputation.
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Affiliation(s)
- L Joseph
- Division of Cardiovascular Diseases, Department of Internal Medicine, University of Iowa Hospitals and Clinics, Iowa City, IA, USA
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23
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Smith MA, Hoffman LM, Beckerle MC. LIM proteins in actin cytoskeleton mechanoresponse. Trends Cell Biol 2014; 24:575-83. [PMID: 24933506 DOI: 10.1016/j.tcb.2014.04.009] [Citation(s) in RCA: 79] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2013] [Revised: 04/23/2014] [Accepted: 04/30/2014] [Indexed: 01/21/2023]
Abstract
The actin cytoskeleton assembles into branched networks or bundles to generate mechanical force for critical cellular processes such as establishment of polarity, adhesion, and migration. Stress fibers (SFs) are contractile actomyosin structures that physically couple to the extracellular matrix through integrin-based focal adhesions (FAs), thereby transmitting force into and across the cell. Recently, LIN-11, Isl1, and MEC-3 (LIM) domain proteins have been implicated in mediating this cytoskeletal mechanotransduction. Among the more well-studied LIM domain adapter proteins is zyxin, a dynamic component of both FAs and SFs. Here we discuss recent research detailing the mechanisms by which SFs adjust their structure and composition to balance mechanical forces and suggest ways that zyxin and other LIM domain proteins mediate mechanoresponse.
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Affiliation(s)
- M A Smith
- Department of Biology, University of Utah, Salt Lake City, UT 84112, USA; Huntsman Cancer Institute, University of Utah, Salt Lake City, UT 84112, USA
| | - L M Hoffman
- Department of Biology, University of Utah, Salt Lake City, UT 84112, USA; Huntsman Cancer Institute, University of Utah, Salt Lake City, UT 84112, USA
| | - M C Beckerle
- Department of Biology, University of Utah, Salt Lake City, UT 84112, USA; Huntsman Cancer Institute, University of Utah, Salt Lake City, UT 84112, USA; Department of Oncological Sciences, University of Utah, Salt Lake City, UT 84112, USA.
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Jones DC, Bennett CR, Smith MA, Scott AM. High-power beam transport through a hollow-core photonic bandgap fiber. Opt Lett 2014; 39:3122-3125. [PMID: 24875992 DOI: 10.1364/ol.39.003122] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
We investigate the use of a seven-cell hollow-core photonic bandgap fiber for transport of CW laser radiation from a single-mode, narrow-linewidth, high-power fiber laser amplifier. Over 90% of the amplifier output was coupled successfully and transmitted through the fiber in a near-Gaussian mode, with negligible backreflection into the source. 100 W of power was successfully transmitted continuously without damage and 160 W of power was transmitted briefly before the onset of thermal lensing in the coupling optics.
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Smith MA, Tellier PP, Roger M, Coutlée F, Franco EL, Richardson H. Determinants of Human Papillomavirus Coinfections among Montreal University Students: The Influence of Behavioral and Biologic Factors. Cancer Epidemiol Biomarkers Prev 2014; 23:812-22. [DOI: 10.1158/1055-9965.epi-13-1255] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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Leal TB, Holden T, Cavalcante L, Allen GO, Schumacher JR, Smith MA, Weiss JM, Neuman HB, LoConte NK. Colon Cancer Staging in Vulnerable Older Adults: Adherence to National Guidelines and Impact on Survival. Ann Hematol Oncol 2014; 1:1012. [PMID: 25914900 PMCID: PMC4405259] [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] [Grants] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
BACKGROUND There is concern that elders are not adequately evaluated prior to colon cancer surgery. We sought to determine adherence with ACOVE-3 (Assessing Care of Vulnerable Elders) quality indicators for pre-operative staging prior to colectomy for colon cancer utilizing the Surveillance, Epidemiology and End Results (SEER)-Medicare linked database (1992-2005). METHODS We determined the proportion of patients aged 75 and older who had preoperative staging prior to colectomy for colon adenocarcinoma. Preoperative staging was defined as abdominopelvic computed tomography or magnetic resonance imaging scan (SCAN) and colonoscopy or flexible sigmoidoscopy (SCOPE). Multivariate logistic regression identified predictors of adherence. Odds ratios were adjusted for comorbidity, socioeconomic status, and disease severity. The association of adherence to ACOVE-3 and survival was quantified. RESULTS Of the 37,862 patients, the majority were 75-84 years, 28% of the patients were ≥85 years. Regarding preoperative staging in the 6-month interval prior to surgical resection, 8% had neither SCAN nor SCOPE, 6% had only SCAN, 43% had only SCOPE, and 43% had both SCAN and SCOPE. Compared to patients who were not staged, those evaluated with either SCOPE alone or SCAN plus SCOPE had lower odds of 3-year mortality. Patients who were staged with SCAN alone had an increased odds of death compared to those who had neither SCAN or SCOPE. CONCLUSIONS These data demonstrate that the majority of vulnerable elders with colon cancer did not receive appropriate preoperative staging prior to resection. The findings also confirm that adherence to ACOVE-3 guidelines is associated with improved long-term survival.
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Affiliation(s)
- TB Leal
- University of Wisconsin Carbone Cancer Center
- University of Wisconsin Department of Medicine, Section of Hematology/Oncology
| | - T Holden
- University of Wisconsin Department of Medicine, Section of Hematology/Oncology
| | - L Cavalcante
- University of Wisconsin Department of Medicine, Section of Hematology/Oncology
| | - GO Allen
- University of Wisconsin Health Innovation Program
| | | | - MA Smith
- University of Wisconsin Health Innovation Program
| | - JM Weiss
- University of Wisconsin Carbone Cancer Center
- University of Wisconsin Department of Medicine, Section of Division of Gastroenterology and Hepatology
| | - HB Neuman
- University of Wisconsin Department of Surgery
| | - NK LoConte
- University of Wisconsin Carbone Cancer Center
- University of Wisconsin Department of Medicine, Section of Hematology/Oncology
- University of Wisconsin Health Innovation Program
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27
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Batarseh KI, Smith MA. Synergistic activities of a silver(I) glutamic acid complex and reactive oxygen species (ROS): a novel antimicrobial and chemotherapeutic agent. Curr Med Chem 2013; 19:3635-40. [PMID: 22680634 DOI: 10.2174/092986712801323216] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2012] [Revised: 04/27/2012] [Accepted: 04/30/2012] [Indexed: 11/22/2022]
Abstract
The antimicrobial and chemotherapeutic activities of a silver(I) glutamic acid complex with the synergistic concomitant generation of reactive oxygen species (ROS) were investigated here. The ROS generation system employed was via Fenton chemistry. The antimicrobial and chemotherapeutic activities were investigated on Staphylococcus aureus ATCC 43300 and Escherichia coli bacteria, and Vero and MCF-7 tumor cell lines, respectively. Antimicrobial activities were conducted by determining minimum inhibitory concentration (MIC), while chemotherapeutic efficacies were done by serial dilution using standard techniques to determine the half maximal inhibitory concentration (IC50). The antimicrobial and chemotherapeutic results obtained were compared with positive control drugs gentamicin, oxacillin, penicillin, streptomycin and cisplatin, a ubiquitously used platinum-based antitumor drug, and with the silver(I) glutamic acid complex and hydrogen peroxide separately. Based on MIC and IC50 values, it was determined that this synergistic approach was very effective at extremely low concentrations, especially when compared with the other drugs evaluated here. This finding might be of great significance regarding metronomic dosing when this synergistic approach is clinically implemented. Since silver at low concentrations exhibits no toxic, mutagenic and carcinogenic activities, this might offer an alternative approach for the development of safer silver-based antimicrobial and chemotherapeutic drugs, thereby reducing or even eliminating the toxicity associated with current drugs. Accordingly, the present approach might be integrated into the systemic clinical treatment of infectious diseases and cancer.
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Affiliation(s)
- K I Batarseh
- NovaGene, LLC 265 High Street 4th Floor Morgantown, WV 26505, USA.
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Blaker PA, Arenas-Hernandez M, Smith MA, Shobowale-Bakre EA, Fairbanks L, Irving PM, Sanderson JD, Marinaki AM. Mechanism of allopurinol induced TPMT inhibition. Biochem Pharmacol 2013; 86:539-47. [PMID: 23770457 DOI: 10.1016/j.bcp.2013.06.002] [Citation(s) in RCA: 77] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2013] [Revised: 06/04/2013] [Accepted: 06/05/2013] [Indexed: 12/16/2022]
Abstract
Up to 1/5 of patients with wildtype thiopurine-S-methyltransferase (TPMT) activity prescribed azathioprine (AZA) or mercaptopurine (MP) demonstrate a skewed drug metabolism in which MP is preferentially methylated to yield methylmercaptopurine (MeMP). This is known as thiopurine hypermethylation and is associated with drug toxicity and treatment non-response. Co-prescription of allopurinol with low dose AZA/MP (25-33%) circumvents this phenotype and leads to a dramatic reduction in methylated metabolites; however, the biochemical mechanism remains unclear. Using intact and lysate red cell models we propose a novel pathway of allopurinol mediated TPMT inhibition, through the production of thioxanthine (TX, 2-hydroxymercaptopurine). In red blood cells pre-incubated with 250 μM MP for 2h prior to the addition of 250 μM TX or an equivalent volume of Earle's balanced salt solution, there was a significant reduction in the concentration of MeMP detected at 4h and 6h in cells exposed to TX (4 h, 1.68, p=0.0005, t-test). TX acts as a direct TPMT inhibitor with an apparent Ki of 0.329 mM. In addition we have confirmed that the mechanism is relevant to in vivo metabolism by demonstrating raised urinary TX levels in patients receiving combination therapy. We conclude that the formation of TX in patients receiving combination therapy with AZA/MP and allopurinol, likely explains the significant reduction of methylated metabolites due to direct TPMT inhibition.
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Affiliation(s)
- P A Blaker
- Department of Gastroenterology, Guy's and St Thomas' NHS Hospitals Foundation Trust, London, UK.
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Perry EA, Castellani RJ, Moreira PI, Nunomura A, Lui Q, Harris PLR, Sayre LM, Szweda PA, Szweda LI, Zhu X, Smith MA, Perry G. Neurofilaments are the major neuronal target of hydroxynonenal-mediated protein cross-links. Free Radic Res 2013; 47:507-10. [PMID: 23566300 DOI: 10.3109/10715762.2013.794265] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Lipid peroxidation generates reactive aldehydes, most notably hydroxynonenal (HNE), which covalently binds amino acid residue side chains leading to protein inactivation and insolubility. Specific adducts of lipid peroxidation have been demonstrated to be intimately associated with pathological lesions of Alzheimer's disease (AD), suggesting that oxidative stress is a major component in the disease. Here, we examined the HNE-cross-linking modifications by using an antibody specific for a lysine-lysine cross-link. Since in a prior study we noted no immunolabeling of neuritic plaques or neurofibrillary tangles but instead found strong labeling of axons, we focused this study on axons. Axonal labeling was examined in mouse sciatic nerve, and immunoblotting showed the cross-link was restricted to neurofilament heavy and medium subunits, which while altering migration, did not indicate larger NF aggregates, indicative of intermolecular cross-links. Examination of mice at various ages showed the extent of modification remaining relatively constant through the life span. These findings demonstrate lipid-cross-linking peroxidation primarily involves lysine-rich neurofilaments and is restricted to intramolecular cross-links.
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Affiliation(s)
- E A Perry
- Department of Biology, The University of Texas at San Antonio, San Antonio, TX, USA
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Reay JL, Smith MA, Riby LM. B vitamins and cognitive performance in older adults: review. ISRN Nutr 2013; 2013:650983. [PMID: 24959550 PMCID: PMC4045270 DOI: 10.5402/2013/650983] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 12/07/2012] [Accepted: 01/29/2013] [Indexed: 11/23/2022]
Abstract
A copious amount of scientific scrutiny has been dedicated to documenting typical and atypical human ageing, with a substantial body of work focusing upon the impact of lifestyle choices. One such lifestyle choice is that of diet and, in particular, micronutrient ingestion. Epidemiological studies have reported positive associations between B vitamin status and cognitive function, including negative associations between biological markers (i.e., homocysteine) of dysregulated one-carbon metabolism and cognitive function. This has led to a surge of randomised control trials (RCTs) investigations into B vitamin therapy. However, results have continuingly failed to show beneficial behavioural effects. Despite this, results reliably show treatment-related increases in B vitamin level and decreases in homocysteine level—both of which have been identified as risk factors for atypical ageing. In this paper we argue that it would be premature to conclude that B vitamin therapy has no potential and that more research is needed to systematically investigate the optimal dose, the therapeutic “window,” and individual differences in therapy responders and nonresponders. We start with a brief look at one-carbon metabolism and then consider the evidence from epidemiological studies and RCTs in relation to three specific B vitamins: folic acid (B9), pyridoxine (B6), and cobamides (B12).
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Affiliation(s)
- J L Reay
- School of Social Sciences and Law, Teesside University, Middlesbrough, Tees Valley TS1 3BA, UK
| | - M A Smith
- Department of Psychology, School of Life Sciences, Northumbria University, Newcastle upon Tyne NE1 8STl, UK
| | - L M Riby
- Department of Psychology, School of Life Sciences, Northumbria University, Newcastle upon Tyne NE1 8STl, UK
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Walker GC, Berry E, Smye SW, Zinov'ev NN, Fitzgerald AJ, Miles RE, Chamberlain M, Smith MA. Two methods for modelling the propagation of terahertz radiation in a layered structure. J Biol Phys 2013; 29:141-8. [PMID: 23345830 DOI: 10.1023/a:1024484523964] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Modelling the interaction of terahertz(THz) radiation with biological tissueposes many interesting problems. THzradiation is neither obviously described byan electric field distribution or anensemble of photons and biological tissueis an inhomogeneous medium with anelectronic permittivity that is bothspatially and frequency dependent making ita complex system to model.A three-layer system of parallel-sidedslabs has been used as the system throughwhich the passage of THz radiation has beensimulated. Two modelling approaches havebeen developed a thin film matrix model anda Monte Carlo model. The source data foreach of these methods, taken at the sametime as the data recorded to experimentallyverify them, was a THz spectrum that hadpassed though air only.Experimental verification of these twomodels was carried out using athree-layered in vitro phantom. Simulatedtransmission spectrum data was compared toexperimental transmission spectrum datafirst to determine and then to compare theaccuracy of the two methods. Goodagreement was found, with typical resultshaving a correlation coefficient of 0.90for the thin film matrix model and 0.78 forthe Monte Carlo model over the full THzspectrum. Further work is underway toimprove the models above 1 THz.
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Affiliation(s)
- G C Walker
- Academic Unit of Medical Physics, University of Leeds, UK
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Fitzgerald AJ, Berry E, Zinov'ev NN, Homer-Vanniasinkam S, Miles RE, Chamberlain JM, Smith MA. Catalogue of human tissue optical properties at terahertz frequencies. J Biol Phys 2013; 29:123-8. [PMID: 23345827 DOI: 10.1023/a:1024428406218] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Recently published studies suggest thatterahertz pulsed imaging will have applications inmedicine and biology, but there iscurrently very little information about the opticalproperties of human tissue at terahertzfrequencies. Such information would be useful forpredicting the feasibility of proposedapplications, optimising acquisition protocols,providing information about variability ofhealthy tissue and supplying data for studies of theinteraction mechanisms. Research ethicscommittee approval was obtained, andmeasurements made from samples of freshlyexcised human tissue, using a broadbandterahertz pulsed imaging system comprisingfrequencies approximately 0.5 to 2.5 THz.Refractive index and linear absorptioncoefficient were found. Reproducibility wasdetermined using blood from one volunteer,which was drawn and measured on consecutivedays. Skin, adipose tissue, striatedmuscle, vein and nerve were measured (to date, from oneindividual). Water had a higher refractiveindex (2.04 ± 0.07) than any tissue.The linear absorption coefficient was higher formuscle than adipose tissue, as expectedfrom the higher hydration of muscle. As these samples camefrom a single subject, there is currentlyinsufficient statistical power to draw firmconclusions, but results suggest that in vivo clinical imaging will be feasible in certainapplications.
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Affiliation(s)
- A J Fitzgerald
- Academic Unit of Medical Physics and Centre of Medical Imaging Research, University of Leeds, Wellcome Wing, Leeds General Infirmary, Great George Street, Leeds, LS1 3EX UK
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Smith MA, Cole KT, Iordanou JC, Kerns DC, Newsom PC, Peitz GW, Schmidt KT. The mu/kappa agonist nalbuphine attenuates sensitization to the behavioral effects of cocaine. Pharmacol Biochem Behav 2013; 104:40-6. [PMID: 23305678 DOI: 10.1016/j.pbb.2012.12.026] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/19/2012] [Revised: 12/07/2012] [Accepted: 12/28/2012] [Indexed: 02/01/2023]
Abstract
Sensitization refers to an increase in sensitivity to a drug and is believed to play a role in the etiology of substance use disorders. The purpose of the present study was to evaluate the ability of the mixed mu/kappa agonist nalbuphine to modulate sensitization to the locomotor and positive reinforcing effects of cocaine. Rats were habituated to a locomotor activity chamber and treated with saline (1.0 ml/kg, ip), cocaine (10 mg/kg, ip), or cocaine+nalbuphine (10 mg/kg, ip) every day for 10 days. Following locomotor activity testing, rats were implanted with intravenous catheters and cocaine self-administration was examined on fixed ratio (FR) and progressive ratio (PR) schedules of reinforcement. Rats treated with cocaine exhibited a progressive increase in locomotor activity over the 10-day treatment period, and this effect was significantly reduced in rats treated with cocaine+nalbuphine. In self-administration tests, rats treated with cocaine exhibited significantly higher levels of responding at a threshold dose of cocaine (0.03 mg/kg/infusion) on both FR and PR schedules than rats treated with saline. This increase in responding at a threshold dose of cocaine was blocked completely in rats treated with cocaine+nalbuphine. These data suggest that nalbuphine attenuates the development of sensitization to the behavioral effects of cocaine.
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Affiliation(s)
- M A Smith
- Department of Psychology, Davidson College, Davidson, NC 28035, USA.
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Abstract
A growing number of reports have related cocaine use with the onset of myocardial infarction in young otherwise healthy individuals. Although the cardiac effects of cocaine have traditionally been attributed to sympathomimetic stimulation, several studies have suggested that cocaine may be directly cardiotoxic. The purpose of this study was to evaluate the cardiotoxic effects of cocaine in an in vitro preparation devoid of sympathetic innervation. Primary cultures of rat cardiac muscle and non-muscle cells were prepared from hearts excised from 3-5-day-old Sprague-Dawley rats. Cultures were exposed to various cocaine concentrations (1 x 10(-7)-1 x 10(-3)m) for 1-24 hr. Beating activity, morphological status and lactate dehydrogenase (LDH) leakage were evaluated following cocaine exposure. A decrease in the beating activity of cultured muscle cells was observed 1 hr after exposure to the highest cocaine concentrations (1 x 10(-5)-1 x 10(-3)m) tested. Similar results were obtained 24 hr after exposure. Morphological alterations in muscle cells were evident only after exposure to the highest concentration (1 x 10(-3)m). Vacuoles appeared 1 hr after cocaine exposure and were replaced by dark granules within 24 hr. LDH release was significantly elevated in the muscle cell cultures exposed to 1 x 10(-3)m cocaine for 24 hr. The pattern of cocaine-induced morphological alterations and enzyme leakage was similar in non-muscle cells. These data suggest that cocaine induces direct toxic effects on both cardiac muscle and non-muscle cells maintained in an environment free of neuronal and hormonal influences.
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Affiliation(s)
- A A Welder
- Department of Pharmacology and Toxicology, College of Pharmacy, The University of Texas, Austin, TX 78712, USA
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Hörst SM, Yelle RV, Buch A, Carrasco N, Cernogora G, Dutuit O, Quirico E, Sciamma-O'Brien E, Smith MA, Somogyi A, Szopa C, Thissen R, Vuitton V. Formation of amino acids and nucleotide bases in a Titan atmosphere simulation experiment. Astrobiology 2012; 12:809-17. [PMID: 22917035 PMCID: PMC3444770 DOI: 10.1089/ast.2011.0623] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
The discovery of large (>100 u) molecules in Titan's upper atmosphere has heightened astrobiological interest in this unique satellite. In particular, complex organic aerosols produced in atmospheres containing C, N, O, and H, like that of Titan, could be a source of prebiotic molecules. In this work, aerosols produced in a Titan atmosphere simulation experiment with enhanced CO (N(2)/CH(4)/CO gas mixtures of 96.2%/2.0%/1.8% and 93.2%/5.0%/1.8%) were found to contain 18 molecules with molecular formulae that correspond to biological amino acids and nucleotide bases. Very high-resolution mass spectrometry of isotopically labeled samples confirmed that C(4)H(5)N(3)O, C(4)H(4)N(2)O(2), C(5)H(6)N(2)O(2), C(5)H(5)N(5), and C(6)H(9)N(3)O(2) are produced by chemistry in the simulation chamber. Gas chromatography-mass spectrometry (GC-MS) analyses of the non-isotopic samples confirmed the presence of cytosine (C(4)H(5)N(3)O), uracil (C(5)H(4)N(2)O(2)), thymine (C(5)H(6)N(2)O(2)), guanine (C(5)H(5)N(5)O), glycine (C(2)H(5)NO(2)), and alanine (C(3)H(7)NO(2)). Adenine (C(5)H(5)N(5)) was detected by GC-MS in isotopically labeled samples. The remaining prebiotic molecules were detected in unlabeled samples only and may have been affected by contamination in the chamber. These results demonstrate that prebiotic molecules can be formed by the high-energy chemistry similar to that which occurs in planetary upper atmospheres and therefore identifies a new source of prebiotic material, potentially increasing the range of planets where life could begin.
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Affiliation(s)
- S M Hörst
- Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, Colorado 80309, USA.
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Hudzik TJ, Maciag C, Smith MA, Caccese R, Pietras MR, Bui KH, Coupal M, Adam L, Payza K, Griffin A, Smagin G, Song D, Swedberg MDB, Brown W. Preclinical pharmacology of AZD2327: a highly selective agonist of the δ-opioid receptor. J Pharmacol Exp Ther 2011; 338:195-204. [PMID: 21444630 DOI: 10.1124/jpet.111.179432] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
In the present article, we summarize the preclinical pharmacology of 4-{(R)-(3-aminophenyl)[4-(4-fluorobenzyl)-piperazin-1-yl]methyl}-N,N-diethylbenzamide (AZD2327), a highly potent and selective agonist of the δ-opioid receptor. AZD2327 binds with sub-nanomolar affinity to the human opioid receptor (K(i) = 0.49 and 0.75 nM at the C27 and F27 isoforms, respectively) and is highly selective (>1000-fold) over the human μ- and κ-opioid receptor subtypes as well as >130 other receptors and channels. In functional assays, AZD2327 shows full agonism at human δ-opioid receptors ([(35)S]GTPγ EC(50) = 24 and 9.2 nM at C27 and F27 isoforms, respectively) and also at the rat and mouse δ-opioid receptors. AZD2327 is active in a wide range of models predictive of anxiolytic activity, including a modified Geller-Seifter conflict test and social interaction test, as well as in antidepressant models, including learned helplessness. In animals implanted with microdialysis probes and then given an acute stressor by pairing electric shock delivery with a flashing light, there is an increase in norepinephrine release into the prefrontal cortex associated with this acute anxiety state. Both the benzodiazepine anxiolytic standard diazepam and AZD2327 blocked this norepinephrine release equally well, and there was no evidence of tolerance to these effects of AZD2327. Overall, these data support the role of the δ-opioid receptor in the regulation of mood, and data suggest that AZD2327 may possess unique antidepressant and anxiolytic activities that could make a novel contribution to the pharmacotherapy of psychiatric disorders.
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Affiliation(s)
- T J Hudzik
- AstraZeneca Research and Development, Wilmington, Delaware, USA.
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Yelle RV, Vuitton V, Lavvas P, Klippenstein SJ, Smith MA, Hörst SM, Cui J. Formation of NH3 and CH2NH in Titan's upper atmosphere. Faraday Discuss 2011; 147:31-49; discussion 83-102. [PMID: 21302541 DOI: 10.1039/c004787m] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The large abundance of NH3 in Titan's upper atmosphere is a consequence of coupled ion and neutral chemistry. The density of NH3 is inferred from the measured abundance of NH4+. NH3 is produced primarily through reaction of NH2 with H2CN, a process neglected in previous models. NH2 is produced by several reactions including electron recombination of CH2NH2+. The density of CH2NH2+ is closely linked to the density of CH2NH through proton exchange reactions and recombination. CH2NH is produced by reaction of N(2D) and NH with ambient hydrocarbons. Thus, production of NH3 is the result of a chain of reactions involving non-nitrile functional groups and the large density of NH3 implies large densities for these associated molecules. This suggests that amine and imine functional groups may be incorporated as well in other, more complex organic molecules.
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Affiliation(s)
- Roger V Yelle
- Department of Planetary Sciences, University of Arizona, Tucson, AZ 85721, USA
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Smith MA, Irving PM, Marinaki AM, Sanderson JD. Review article: malignancy on thiopurine treatment with special reference to inflammatory bowel disease. Aliment Pharmacol Ther 2010; 32:119-30. [PMID: 20412066 DOI: 10.1111/j.1365-2036.2010.04330.x] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
BACKGROUND Immunosuppression is a risk factor for carcinogenesis. Thiopurines specifically contribute to this. As thiopurines are used more aggressively in the treatment of IBD, it is likely that we will see more thiopurine-related malignancy. AIM To review the literature, exploring how immunosuppression, thiopurines specifically, might cause cancer and which malignancies occur in practice, placing specific emphasis on IBD cohorts. METHODS Search terms included 'malignancy' 'cancer' 'azathioprine' 'mercaptopurine' 'tioguanine (thioguanine)' 'thiopurine' and 'inflammatory bowel disease' 'Crohn's disease' 'ulcerative colitis'. We also searched for specific cancers (lymphoma, colorectal cancer, skin cancer, cervical cancer) and reviewed the reference lists of the articles detected. RESULTS Immunosuppression is associated with an increased risk of cancer. Thiopurines are associated with specific additional risks. In IBD cohorts, very few thiopurine-related malignancies have been reported. However, studies suggest a relative risk of 4-5 for lymphoma. This still translates into a low actual risk, (one extra lymphoma in every 300-1400 years of thiopurine treatment). CONCLUSIONS Whilst we must be aware of this risk and counsel our patients appropriately, thiopurines remain a mainstay of IBD therapy. We present practical advice aimed at minimizing our patients' risk of developing malignancy, whilst optimizing the benefits that thiopurines can provide.
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Affiliation(s)
- M A Smith
- Department of Gastroenterology Guy's & St. Thomas' NHS Foundation Trust, London, UK
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Abstract
Inflammatory bowel disease (IBD) affects body image, relationships, family planning, fertility and pregnancy outcomes. However, the common misconception that IBD is a contraindication, or serious concern, in pregnancy is essentially a myth. Most patients with IBD can expect to have uneventful pregnancies. We present an overview of the management of IBD during pregnancy, including management in those planning pregnancy, the suitability of relevant medication during pregnancy and breast feeding, investigation and monitoring of IBD during pregnancy, surgical management and considerations relating to delivery. While there are some definite alterations required in the management of IBD during pregnancy, management is essentially unchanged. With close attention to aspects such as nutrition and smoking cessation, and optimal disease control in the run-up to and during pregnancy, we have an opportunity to help our patients with IBD achieve good pregnancy outcomes.
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Affiliation(s)
- M A Smith
- Department of Gastroenterology, Guy's & St Thomas' NHS Foundation Trust , London , UK
| | - J D Sanderson
- Department of Gastroenterology, Guy's & St Thomas' NHS Foundation Trust , London , UK
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Bonda DJ, Bajić VP, Spremo-Potparevic B, Casadesus G, Zhu X, Smith MA, Lee HG. Review: cell cycle aberrations and neurodegeneration. Neuropathol Appl Neurobiol 2010; 36:157-63. [PMID: 20059701 DOI: 10.1111/j.1365-2990.2010.01064.x] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The cell cycle is a highly regulated and fundamental cellular process that involves complex feedback regulation of many proteins, and any compromise to its integrity elicits dire consequences for the cell. For example, in neurodegenerative diseases such as Alzheimer disease (AD), evidence for abnormal cell cycle re-entry precedes other hallmarks of disease and as such, implicates cell cycle aberrations in the aetiology of AD. The mechanism(s) for cell cycle re-entry in AD, however, remain unclear. Current theory suggests it to be part of a combination of early events that together elicit the degenerative pathology and cognitive phenotype consistent with the disease. We propose a 'Two-Hit Hypothesis' that highlights the concerted interaction between cell cycle alterations and oxidative stress that combine to produce neurodegeneration. Here, we review the evidence implicating cell cycle mechanisms in AD and how such changes, especially in combination with oxidative stress, would lead to a cascade of events leading to disease. Based on this concept, we propose new opportunities for disease treatment.
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Affiliation(s)
- D J Bonda
- Departments of Pathology, Case Western Reserve University, Cleveland, Ohio 44106, USA
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Smith MA, Walmsley JP, Phillips TJ, Pinchbeck GL, Booth TM, Greet TRC, Richardson DW, Ross MW, Schramme MC, Singer ER, Smith RK, Clegg PD. Effect of age at presentation on outcome following arthroscopic debridement of subchondral cystic lesions of the medial femoral condyle: 85 horses (1993-2003). Equine Vet J 2010; 37:175-80. [PMID: 15779633 DOI: 10.2746/0425164054223741] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [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: 11/19/2022]
Abstract
REASONS FOR PERFORMING STUDY Subchondral cystic lesions of the medial femoral condyle (SCMFC) are well documented in horses < or =3 years; arthroscopic debridement or enucleation of the cyst is currently the surgical treatment of choice. However, studies of occurence and outcome following surgery in older horses are lacking. OBJECTIVE To identify factors important in outcome for horses with SCMFC treated by arthroscopic debridement. HYPOTHESIS Age of horse at presentation has a significant influence on return to work following arthroscopic treatment for SCMFC. Clinical and diagnostic findings are also significant with respect to prognosis. METHODS A retrospective review of medical records from 6 equine referral centres identified 85 horses that underwent arthroscopic debridement of SCMFC. Clinical examination, radiographic and arthroscopic findings were analysed together with follow-up data. Univariable analysis and multivariable logistic regression models were used to determine factors affecting return to soundness. Event-time analysis was performed to evaluate return to work. RESULTS Older horses (>3 years) were less likely to return to soundness (P = 0.02) or to work (P = 0.04) than younger horses (< or = 3 years). Of 39 horses age 0-3 years, 25 (64%, 95% CI 49-79%) returned to soundness. Of 46 horses age >3 years, 16 (35%,95% CI 21-49%) returned to soundness. In addition, cartilage damage at sites other than the SCMFC negatively affected prognosis (P = 0.05). The hospital where treatment was performed had no influence on return to soundness. CONCLUSIONS Older horses carry a worse prognosis for both return to soundness and return to work. POTENTIAL RELEVANCE It is important for clients to be made aware of the difference in outcome between age groups.
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Affiliation(s)
- M A Smith
- Department of Veterinary Clinical Science, University of Liverpool, Leahurst, Neston, Wirral CH64 7TE, UK
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Smith MA, Marinaki AM, Arenas M, Shobowale-Bakre M, Lewis CM, Ansari A, Duley J, Sanderson JD. Novel pharmacogenetic markers for treatment outcome in azathioprine-treated inflammatory bowel disease. Aliment Pharmacol Ther 2009; 30:375-84. [PMID: 19500084 DOI: 10.1111/j.1365-2036.2009.04057.x] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
BACKGROUND Azathioprine (AZA) pharmacogenetics are complex and much studied. Genetic polymorphism in TPMT is known to influence treatment outcome. Xanthine oxidase/dehydrogenase (XDH) and aldehyde oxidase (AO) compete with TPMT to inactivate AZA. AIM To assess whether genetic polymorphism in AOX1, XDH and MOCOS (the product of which activates the essential cofactor for AO and XDH) is associated with AZA treatment outcome in IBD. METHODS Real-time PCR was conducted for a panel of single nucleotide polymorphism (SNPs) in AOX1, XDH and MOCOS using TaqMan SNP genotyping assays in a prospective cohort of 192 patients receiving AZA for IBD. RESULTS Single nucleotide polymorphism AOX1 c.3404A > G (Asn1135Ser, rs55754655) predicted lack of AZA response (P = 0.035, OR 2.54, 95%CI 1.06-6.13) and when combined with TPMT activity, this information allowed stratification of a patient's chance of AZA response, ranging from 86% in patients where both markers were favourable to 33% where they were unfavourable (P < 0.0001). We also demonstrated a weak protective effect against adverse drug reactions (ADRs) from SNPs XDH c.837C > T (P = 0.048, OR 0.23, 95% CI 0.05-1.05) and MOCOS c.2107A > C, (P = 0.058 in recessive model, OR 0.64, 95%CI 0.36-1.15), which was stronger where they coincided (P = 0.019). CONCLUSION These findings have important implications for clinical practice and our understanding of AZA metabolism.
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Affiliation(s)
- M A Smith
- Department of Gastroenterology, Guy's & St. Thomas' NHS Foundation Trust, London, UK
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Carleton BC, Poole RL, Smith MA, Leeder JS, Ghannadan R, Ross CJD, Phillips MS, Hayden MR. Adverse drug reaction active surveillance: developing a national network in Canada's children's hospitals. Pharmacoepidemiol Drug Saf 2009; 18:713-21. [DOI: 10.1002/pds.1772] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Meurer WJ, Sánchez BN, Smith MA, Lisabeth LD, Majersik JJ, Brown DL, Uchino K, Bonikowski FP, Mendizabal JE, Zahuranec DB, Morgenstern LB. Predicting ischaemic stroke subtype from presenting systolic blood pressure: the BASIC Project. J Intern Med 2009; 265:388-96. [PMID: 19019190 PMCID: PMC2707751 DOI: 10.1111/j.1365-2796.2008.02022.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE We hypothesized that low presenting systolic blood pressure (SBP) predicted cardioembolic stroke aetiology. DESIGN Active and passive surveillance were used to identify all ischaemic strokes as part of the Brain Attack Surveillance in Corpus Christi (BASIC) population-based study. Multinomial logistic regression was used to examine the association between stroke subtype and first documented SBP in the medical record. SETTING Nueces County, TX, USA (313,645 residents in 2000). The community is urban with the majority of the population residing in the city of Corpus Christi. The area is served by seven adult acute care hospitals. PATIENTS Three hundred and eight cases with completed ischaemic stroke and determined subtype aetiology between January 2000 and December 2002. RESULTS Lower presenting SBP was associated with stroke subtype (P = 0.001). This association remained significant in the final model adjusted for age and history of coronary artery disease. The odds of cardioembolic versus small vessel occlusion increased by 20% (OR = 1.20, 95% CI: 1.07-1.35) for every 10 mmHg decrease in presenting SBP. Other covariates including race/ethnicity, gender, history of hypertension, and diabetes were neither significant predictors of stroke subtype, nor did they confound the association of SBP and stroke subtype. A 5 year increase in age increased the odds of cardioembolic subtype by 25% (OR = 1.25, 95% CI: 1.07-1.47). CONCLUSIONS Lower initial SBP and older age at ischaemic stroke presentation were associated with cardioembolic stroke. Suspicion of cardioembolic stroke should be increased in those presenting with low SBP.
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Affiliation(s)
- W J Meurer
- Stroke Program, University of Michigan Health System, USA
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48
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Abstract
Multiple lines of evidence demonstrate that oxidative stress is an early event in Alzheimer's disease (AD), occurring prior to cytopathology, and therefore may play a key pathogenic role in AD. Oxidative stress not only temporally precedes the pathological lesions of the disease but also activates cell signaling pathways, which, in turn, contribute to lesion formation and, at the same time, provoke cellular responses such as compensatory upregulation of antioxidant enzymes found in vulnerable neurons in AD. In this review, we provide an overview of the evidence of oxidative stress and compensatory responses that occur in AD, particularly focused on potential sources of oxidative stress and the roles and mechanism of activation of stress-activated protein kinase pathways.
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Affiliation(s)
- B Su
- Department of Pathology, Case Western Reserve University, Cleveland, Ohio 44106, USA
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49
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Wong E, Carleton BC, Wright DFB, Smith MA, Verbeek L, Hildebrand CA, Stannard P, Vaillancourt R, Elliot-Miller P, Ross CJD, Hayden MR. Genotypic Approaches to Therapy in Children (GATC): using information technology to improve drug safety. Stud Health Technol Inform 2009; 143:209-214. [PMID: 19380938] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Adverse drug reactions (ADRs) are a major cause of morbidity and mortality in children. Current models of ADR surveillance have repeatedly demonstrated little pragmatic value to practicing clinicians. ADR reporting rates in the US and Canada suggest that only 5% of ADRs are reported. The Genotypic Approaches to Therapy in Children (GATC) network was established to identify and solve drug safety problems in paediatrics. We hypothesized that genetic polymorphisms underlie a significant portion of concentration-dependent ADRs in children. Our objective was to establish an ADR active surveillance network in paediatric hospitals across Canada. Surveillance clinicians evaluate clinical information from ADR cases and drug-matched controls, and collected DNA samples from all patients. The surveillance network will enable the identification of predictive genomic-markers for ADRs. With this knowledge, children at risk can be identified before therapy is initiated and enable personalized adjustments to therapy based on genetic make-up.
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Affiliation(s)
- E Wong
- Children's Hospital of Eastern Ontario, Ottawa, ON, Canada.
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50
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Hisadome K, Smith MA, Choudhury AI, Claret M, Withers DJ, Ashford MLJ. 5-HT inhibition of rat insulin 2 promoter Cre recombinase transgene and proopiomelanocortin neuron excitability in the mouse arcuate nucleus. Neuroscience 2008; 159:83-93. [PMID: 19135134 PMCID: PMC2661429 DOI: 10.1016/j.neuroscience.2008.12.003] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2008] [Revised: 11/28/2008] [Accepted: 12/02/2008] [Indexed: 11/28/2022]
Abstract
A number of anti-obesity agents have been developed that enhance hypothalamic 5-HT transmission. Various studies have demonstrated that arcuate neurons, which express proopiomelanocortin peptides (POMC neurons), and neuropeptide Y with agouti-related protein (NPY/AgRP) neurons, are components of the hypothalamic circuits responsible for energy homeostasis. An additional arcuate neuron population, rat insulin 2 promoter Cre recombinase transgene (RIPCre) neurons, has recently been implicated in hypothalamic melanocortin circuits involved in energy balance. It is currently unclear how 5-HT modifies neuron excitability in these local arcuate neuronal circuits. We show that 5-HT alters the excitability of the majority of mouse arcuate RIPCre neurons, by either hyperpolarization and inhibition or depolarization and excitation. RIPCre neurons sensitive to 5-HT, predominantly exhibit hyperpolarization and pharmacological studies indicate that inhibition of neuronal firing is likely to be through 5-HT1F receptors increasing current through a voltage-dependent potassium conductance. Indeed, 5-HT1F receptor immunoreactivity co-localizes with RIPCre green fluorescent protein expression. A minority population of POMC neurons also respond to 5-HT by hyperpolarization, and this appears to be mediated by the same receptor-channel mechanism. As neither POMC nor RIPCre neuronal populations display a common electrical response to 5-HT, this may indicate that sub-divisions of POMC and RIPCre neurons exist, perhaps serving different outputs.
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Affiliation(s)
- K Hisadome
- Biomedical Research Institute, Ninewells Hospital and Medical School, University of Dundee, Dundee, DD1 9SY, Scotland, UK
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