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Lee H, Sam K, Coulon F, De Gisi S, Notarnicola M, Labianca C. Recent developments and prospects of sustainable remediation treatments for major contaminants in soil: A review. Sci Total Environ 2024; 912:168769. [PMID: 38008308 DOI: 10.1016/j.scitotenv.2023.168769] [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] [Subscribe] [Scholar Register] [Received: 07/31/2023] [Revised: 11/17/2023] [Accepted: 11/19/2023] [Indexed: 11/28/2023]
Abstract
Rapid industrialisation and urbanisation are contributing to the entry of emerging contaminants into the environment, posing a significant threat to soil health and quality. Therefore, several remediation technologies have been investigated and tested at a field scale to address the issue. However, these remediation technologies face challenges related to cost-effectiveness, environmental concerns, secondary pollution due to the generation of by-products, long-term pollution leaching risks, and social acceptance. Overcoming these constraints necessitates the implementation of sustainable remediation methodologies that prioritise approaches with minimal environmental ramifications and the most substantial net social and economic advantages. Hence, this review delves into diverse contaminants that threaten soil health and quality. Moreover, it outlines the research imperatives for advancing innovative remediation techniques and effective management strategies to tackle this concern. The review discusses a remediation treatment train approach that encourages resource recovery, strengthens the circular economy, and employs a Life Cycle Assessment (LCA) framework to assess the environmental impacts of different remediation strategies. Additionally, the study explores mechanisms to integrate sustainability principles into soil remediation practices. It underscores the necessity for a comprehensive and systematic approach that takes into account the economic, social, and environmental consequences of remediation methodologies in the development of sustainable solutions.
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Affiliation(s)
- H Lee
- College of Engineering and Physical Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
| | - K Sam
- School of the Environment, Geography and Geoscience, University of Portsmouth, University House, Winston Churchill Ave, Portsmouth PO1 2UP, UK
| | - F Coulon
- School of Water, Energy and Environment, Cranfield University, Cranfield, Bedfordshire MK43 0AL, UK
| | - S De Gisi
- Department of Civil, Environmental, Land, Building Engineering and Chemistry (DICATECh), Polytechnic University of Bari, Via E. Orabona n. 4, 70125 Bari, Italy
| | - M Notarnicola
- Department of Civil, Environmental, Land, Building Engineering and Chemistry (DICATECh), Polytechnic University of Bari, Via E. Orabona n. 4, 70125 Bari, Italy
| | - C Labianca
- Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, China; Arup, Level 5, Festival Walk, 80 Tat Chee Avenue, Kowloon Tong, Hong Kong, China.
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Ismaeel A, Tai APK, Santos EG, Maraia H, Aalto I, Altman J, Doležal J, Lembrechts JJ, Camargo JL, Aalto J, Sam K, Avelino do Nascimento LC, Kopecký M, Svátek M, Nunes MH, Matula R, Plichta R, Abera T, Maeda EE. Patterns of tropical forest understory temperatures. Nat Commun 2024; 15:549. [PMID: 38263406 PMCID: PMC10805846 DOI: 10.1038/s41467-024-44734-0] [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] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2023] [Accepted: 01/02/2024] [Indexed: 01/25/2024] Open
Abstract
Temperature is a fundamental driver of species distribution and ecosystem functioning. Yet, our knowledge of the microclimatic conditions experienced by organisms inside tropical forests remains limited. This is because ecological studies often rely on coarse-gridded temperature estimates representing the conditions at 2 m height in an open-air environment (i.e., macroclimate). In this study, we present a high-resolution pantropical estimate of near-ground (15 cm above the surface) temperatures inside forests. We quantify diurnal and seasonal variability, thus revealing both spatial and temporal microclimate patterns. We find that on average, understory near-ground temperatures are 1.6 °C cooler than the open-air temperatures. The diurnal temperature range is on average 1.7 °C lower inside the forests, in comparison to open-air conditions. More importantly, we demonstrate a substantial spatial variability in the microclimate characteristics of tropical forests. This variability is regulated by a combination of large-scale climate conditions, vegetation structure and topography, and hence could not be captured by existing macroclimate grids. Our results thus contribute to quantifying the actual thermal ranges experienced by organisms inside tropical forests and provide new insights into how these limits may be affected by climate change and ecosystem disturbances.
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Affiliation(s)
- Ali Ismaeel
- Earth and Environmental Sciences Programme, Faculty of Science, The Chinese University of Hong Kong, Hong Kong, China
| | - Amos P K Tai
- Earth and Environmental Sciences Programme, Faculty of Science, The Chinese University of Hong Kong, Hong Kong, China
- State Key Laboratory of Agrobiotechnology, and Institute of Environment, Energy and Sustainability, The Chinese University of Hong Kong, Hong Kong, China
| | - Erone Ghizoni Santos
- Department of Geosciences and Geography, University of Helsinki, P.O. Box 68, FI-00014, Helsinki, Finland
| | - Heveakore Maraia
- Institute of Entomology, Biology Centre of the Czech Academy of Sciences, České Budějovice, Branisovska 31, CZ 370 05, Czech Republic
- Faculty of Science, University of South Bohemia, Branisovska 1760, CZ 370 05, České Budějovice, Czechia
| | - Iris Aalto
- Department of Geosciences and Geography, University of Helsinki, P.O. Box 68, FI-00014, Helsinki, Finland
- School of GeoSciences, University of Edinburgh, Edinburgh, EH8 9XP, UK
| | - Jan Altman
- Institute of Botany of the Czech Academy of Sciences, Zámek 1, CZ-252 43, Průhonice, Czech Republic
- Faculty of Forestry and Wood Sciences, University of Life Sciences Prague, Kamýcká 129, CZ-16521, Praha 6-Suchdol, Prague, Czech Republic
| | - Jiří Doležal
- Faculty of Science, University of South Bohemia, Branisovska 1760, CZ 370 05, České Budějovice, Czechia
- Institute of Botany of the Czech Academy of Sciences, Zámek 1, CZ-252 43, Průhonice, Czech Republic
| | - Jonas J Lembrechts
- Research Group Plants and Ecosystems, University of Antwerp, 2610, Wilrijk, Belgium
| | - José Luís Camargo
- Biological Dynamics of Forest Fragment Project (BDFFP) - National Institute of Amazonian Research (INPA), CP 478, 69067-375, Manaus, AM, Brazil
| | - Juha Aalto
- Department of Geosciences and Geography, University of Helsinki, P.O. Box 68, FI-00014, Helsinki, Finland
- Finnish Meteorological Institute, P.O. Box 503, FI-00101, Helsinki, Finland
| | - Kateřina Sam
- Institute of Entomology, Biology Centre of the Czech Academy of Sciences, České Budějovice, Branisovska 31, CZ 370 05, Czech Republic
- Faculty of Science, University of South Bohemia, Branisovska 1760, CZ 370 05, České Budějovice, Czechia
| | | | - Martin Kopecký
- Institute of Botany of the Czech Academy of Sciences, Zámek 1, CZ-252 43, Průhonice, Czech Republic
- Faculty of Forestry and Wood Sciences, University of Life Sciences Prague, Kamýcká 129, CZ-16521, Praha 6-Suchdol, Prague, Czech Republic
| | - Martin Svátek
- Department of Forest Botany, Dendrology and Geobiocoenology, Faculty of Forestry and Wood Technology, Mendel University in Brno, Zemědělská 3, 61300, Brno, Czech Republic
| | - Matheus Henrique Nunes
- Department of Geosciences and Geography, University of Helsinki, P.O. Box 68, FI-00014, Helsinki, Finland
- Department of Geographical Sciences, University of Maryland, College Park, MD, 20742, USA
| | - Radim Matula
- Faculty of Forestry and Wood Sciences, University of Life Sciences Prague, Kamýcká 129, CZ-16521, Praha 6-Suchdol, Prague, Czech Republic
| | - Roman Plichta
- Department of Forest Botany, Dendrology and Geobiocoenology, Faculty of Forestry and Wood Technology, Mendel University in Brno, Zemědělská 3, 61300, Brno, Czech Republic
| | - Temesgen Abera
- Department of Geosciences and Geography, University of Helsinki, P.O. Box 68, FI-00014, Helsinki, Finland
- Department of Environmental Informatics, Faculty of Geography, Philipps Universität-Marburg, Deutschhausstrasse, 12, 35032, Marburg, Germany
| | - Eduardo Eiji Maeda
- Department of Geosciences and Geography, University of Helsinki, P.O. Box 68, FI-00014, Helsinki, Finland.
- Finnish Meteorological Institute, P.O. Box 503, FI-00101, Helsinki, Finland.
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McKetton L, Venkatraghavan L, Rosen C, Mandell DM, Sam K, Sobczyk O, Poublanc J, Gray E, Crawley A, Duffin J, Fisher JA, Mikulis DJ. Improved White Matter Cerebrovascular Reactivity after Revascularization in Patients with Steno-Occlusive Disease. AJNR Am J Neuroradiol 2018; 40:45-50. [PMID: 30573457 DOI: 10.3174/ajnr.a5912] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2018] [Accepted: 10/08/2018] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE One feature that patients with steno-occlusive cerebrovascular disease have in common is the presence of white matter (WM) lesions on MRI. The purpose of this study was to evaluate the effect of direct surgical revascularization on impaired WM cerebrovascular reactivity in patients with steno-occlusive disease. MATERIALS AND METHODS We recruited 35 patients with steno-occlusive disease, Moyamoya disease (n = 24), Moyamoya syndrome (n = 3), atherosclerosis (n = 6), vasculitis (n = 1), and idiopathic stenosis (n = 1), who underwent unilateral brain revascularization using a direct superficial temporal artery-to-MCA bypass (19 women; mean age, 45.8 ± 16.5 years). WM cerebrovascular reactivity was measured preoperatively and postoperatively using blood oxygen level-dependent (BOLD) MR imaging during iso-oxic hypercapnic changes in end-tidal carbon dioxide and was expressed as %Δ BOLD MR signal intensity per millimeter end-tidal partial pressure of CO2. RESULTS WM cerebrovascular reactivity significantly improved after direct unilateral superficial temporal artery-to-middle cerebral artery (STA-MCA) bypass in the revascularized hemisphere in the MCA territory (mean ± SD, -0.0005 ± 0.053 to 0.053 ± 0.046 %BOLD/mm Hg; P < .0001) and in the anterior cerebral artery territory (mean, 0.0015 ± 0.059 to 0.021 ± 0.052 %BOLD/mm Hg; P = .005). There was no difference in WM cerebrovascular reactivity in the ipsilateral posterior cerebral artery territory nor in the vascular territories of the nonrevascularized hemisphere (P < .05). CONCLUSIONS Cerebral revascularization surgery is an effective treatment for reversing preoperative cerebrovascular reactivity deficits in WM. In addition, direct-STA-MCA bypass may prevent recurrence of preoperative symptoms.
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Affiliation(s)
- L McKetton
- From the Division of Neuroradiology, Joint Department of Medical Imaging (L.M., C.R., D.M.M., K.S., O.S., J.P., E.G., A.C., D.J.M.)
| | - L Venkatraghavan
- Department of Anesthesia and Pain Management (L.V., J.A.F.), University Health Network, Toronto, Ontario, Canada
| | - C Rosen
- From the Division of Neuroradiology, Joint Department of Medical Imaging (L.M., C.R., D.M.M., K.S., O.S., J.P., E.G., A.C., D.J.M.)
| | - D M Mandell
- From the Division of Neuroradiology, Joint Department of Medical Imaging (L.M., C.R., D.M.M., K.S., O.S., J.P., E.G., A.C., D.J.M.)
| | - K Sam
- From the Division of Neuroradiology, Joint Department of Medical Imaging (L.M., C.R., D.M.M., K.S., O.S., J.P., E.G., A.C., D.J.M.).,Russell H. Morgan Department of Radiology and Radiological Science (K.S.), John Hopkins School of Medicine, Baltimore, Maryland
| | - O Sobczyk
- From the Division of Neuroradiology, Joint Department of Medical Imaging (L.M., C.R., D.M.M., K.S., O.S., J.P., E.G., A.C., D.J.M.)
| | - J Poublanc
- From the Division of Neuroradiology, Joint Department of Medical Imaging (L.M., C.R., D.M.M., K.S., O.S., J.P., E.G., A.C., D.J.M.)
| | - E Gray
- From the Division of Neuroradiology, Joint Department of Medical Imaging (L.M., C.R., D.M.M., K.S., O.S., J.P., E.G., A.C., D.J.M.)
| | - A Crawley
- From the Division of Neuroradiology, Joint Department of Medical Imaging (L.M., C.R., D.M.M., K.S., O.S., J.P., E.G., A.C., D.J.M.)
| | - J Duffin
- Department of Physiology (J.D., J.A.F.).,Institute of Medical Sciences (J.D., J.A.F., D.J.M.), University of Toronto, Toronto, Ontario, Canada
| | - J A Fisher
- Department of Anesthesia and Pain Management (L.V., J.A.F.), University Health Network, Toronto, Ontario, Canada.,Department of Physiology (J.D., J.A.F.).,Institute of Medical Sciences (J.D., J.A.F., D.J.M.), University of Toronto, Toronto, Ontario, Canada
| | - D J Mikulis
- From the Division of Neuroradiology, Joint Department of Medical Imaging (L.M., C.R., D.M.M., K.S., O.S., J.P., E.G., A.C., D.J.M.) .,Institute of Medical Sciences (J.D., J.A.F., D.J.M.), University of Toronto, Toronto, Ontario, Canada
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Sam K, Zabbey N. Contaminated land and wetland remediation in Nigeria: Opportunities for sustainable livelihood creation. Sci Total Environ 2018; 639:1560-1573. [PMID: 29929319 DOI: 10.1016/j.scitotenv.2018.05.266] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [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: 01/17/2018] [Revised: 05/16/2018] [Accepted: 05/22/2018] [Indexed: 06/08/2023]
Abstract
The Niger Delta region of Nigeria is one of the most crude oil impacted deltas globally. The region has experienced over five decades of oil related contamination of the total environment (air, soil, water and biota). In 2011, UNEP released a seminal report on oil impact on Ogoniland environments, which up scaled demands for urgent clean up and restoration of degraded bio-resource rich environments of the Niger Delta, starting from Ogoniland. The Nigerian Government demonstrated renewed political will to remediate contaminated sites in Ogoniland with a launch of the clean-up exercise in June 2016. Stakeholders' expectations from the clean-up include not only environmental remediation but also restoration and creation of sustainable livelihood opportunities to reduce poverty in the region. Most studies have focused on the environmental restoration aspect and identified bioremediation as the likely appropriate remediation approach for Ogoniland, given its low environmental footprints, and low-cost burden on the weak and overstretched economy of Nigeria. This study mapped opportunities for sustainable livelihood creation during the Ogoniland remediation and restoration exercise. Given the value chain of bioremediation and its ancillary activities, the study analysed opportunities and mechanisms for skilled and unskilled job creation and prospects for sustainable livelihoods and knock-on effects. It is anticipated that the clean-up process would lead to economic prosperity and mitigate resource-driven conflicts in the Niger Delta. The study provides an exemplar for waste-to-wealth transformation in regions where natural resource mining has impacted communities, and has dislocated local economies and age-old livelihood structures.
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Affiliation(s)
- K Sam
- Environment and Conservation Unit, Centre for Environment, Human Rights and Development, Legacy Centre, Abuja Lane, Port Harcourt, Nigeria.
| | - N Zabbey
- Environment and Conservation Unit, Centre for Environment, Human Rights and Development, Legacy Centre, Abuja Lane, Port Harcourt, Nigeria; Department of Fisheries, Faculty of Agriculture, University of Port Harcourt, PMB 5323, East-West Road, Choba, Rivers State, Nigeria
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Benveniste APA, Ebuoma LO, Jonna A, Sam K, Severs FJ, Roark A, Sepulveda KA, Tamara OP, Sedgwick EE. Abstract P4-02-13: Can background parenchymal enhancement (BPE) predict the chance of multicentric/ bilateral breast cancer on staging breast MRI? Cancer Res 2018. [DOI: 10.1158/1538-7445.sabcs17-p4-02-13] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Purpose: Can background parenchymal enhancement (BPE) predict the chance of multicentric/ bilateral breast cancer on staging Breast MRI?
Materials and Methods: Retrospective review of women diagnosed with breast cancer who underwent a breast MRI for staging of disease was performed at a single institution from October 2012 to September 2015.
Results: Breast MRI for staging was done for 435 patients diagnosed with breast cancer. Ages ranging from 24 to 86 years old (median, 52 years); sizes ranging from 0.5 to 13.5 cm (mean, 3.5 cm). 29 patients (7 %) had biopsy-proven second tumors in the same breast but different quadrant as the primary tumor or in the contralateral breast. From the 435 patients, 304 had minimal/ mild BPE and 103 had moderate/marked BPE (28 missing). Of the patients with an invasive primary cancer and a second tumor in the same breast but different quadrant as the primary tumor or in the contralateral breast, 12 of 29 patients had discordance in subtypes between the primary and secondary tumors (41%) and 17 of 29 had concordance in the subtypes between the primary and secondary tumors (59%). 6.3% (19 out 304) of patients with minimal/ mild BPE had multicentric /bilateral disease and 9.7% (10 out 103) of patients with moderate/ marked BPE had multicentric/ bilateral breast cancer.
Conclusion: 435 patients with recent diagnosis of breast cancer who underwent staging breast MRI for diagnosis of additional sites of disease, 7% was diagnosed with an additional site of cancer. From these group of patients, approximately 6% had other site of disease among patients who had minimal/ mild BPE in the breast MRI versus 10% of patients with moderate/marked BPE. BPE may play a role in the setting of multicentric/ bilateral breast cancer.
Citation Format: Benveniste APA, Ebuoma LO, Jonna A, Sam K, Severs Jr. FJ, Roark A, Sepulveda KA, Tamara O-P, Sedgwick EE. Can background parenchymal enhancement (BPE) predict the chance of multicentric/ bilateral breast cancer on staging breast MRI? [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P4-02-13.
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Affiliation(s)
| | - LO Ebuoma
- Baylor College of Medicine, Houston, TX
| | - A Jonna
- Baylor College of Medicine, Houston, TX
| | - K Sam
- Baylor College of Medicine, Houston, TX
| | - FJ Severs
- Baylor College of Medicine, Houston, TX
| | - A Roark
- Baylor College of Medicine, Houston, TX
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Segar ST, Volf M, Zima Jnr J, Isua B, Sisol M, Sam L, Sam K, Souto-Vilarós D, Novotny V. Speciation in a keystone plant genus is driven by elevation: a case study in New Guinean Ficus. J Evol Biol 2016; 30:512-523. [DOI: 10.1111/jeb.13020] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2016] [Revised: 11/11/2016] [Accepted: 11/16/2016] [Indexed: 11/29/2022]
Affiliation(s)
- S. T. Segar
- Faculty of Science; University of South Bohemia; Ceske Budejovice Czech Republic
- Biology Centre CAS; Institute of Entomology; Ceske Budejovice Czech Republic
| | - M. Volf
- Faculty of Science; University of South Bohemia; Ceske Budejovice Czech Republic
- Biology Centre CAS; Institute of Entomology; Ceske Budejovice Czech Republic
| | - J. Zima Jnr
- Biology Centre CAS; Institute of Entomology; Ceske Budejovice Czech Republic
- Institute of Botany; Academy of Sciences of the Czech Republic; Třeboň Czech Republic
| | - B. Isua
- New Guinea Binatang Research Center; Madang Papua New Guinea
| | - M. Sisol
- New Guinea Binatang Research Center; Madang Papua New Guinea
| | - L. Sam
- Environmental Futures Research Institute; Griffith University; Brisbane Qld Australia
- Griffith School of Environment; Griffith University; Brisbane Qld Australia
| | - K. Sam
- Faculty of Science; University of South Bohemia; Ceske Budejovice Czech Republic
- Biology Centre CAS; Institute of Entomology; Ceske Budejovice Czech Republic
| | - D. Souto-Vilarós
- Faculty of Science; University of South Bohemia; Ceske Budejovice Czech Republic
- Biology Centre CAS; Institute of Entomology; Ceske Budejovice Czech Republic
| | - V. Novotny
- Faculty of Science; University of South Bohemia; Ceske Budejovice Czech Republic
- Biology Centre CAS; Institute of Entomology; Ceske Budejovice Czech Republic
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Sam K, Crawley AP, Poublanc J, Conklin J, Sobczyk O, Mandell DM, Duffin J, Venkatraghavan L, Fisher JA, Black SE, Mikulis DJ. Vascular Dysfunction in Leukoaraiosis. AJNR Am J Neuroradiol 2016; 37:2258-2264. [PMID: 27492072 DOI: 10.3174/ajnr.a4888] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2015] [Accepted: 06/07/2016] [Indexed: 01/04/2023]
Abstract
BACKGROUND AND PURPOSE The pathogenesis of leukoaraiosis has long been debated. This work addresses a less well-studied mechanism, cerebrovascular reactivity, which could play a leading role in the pathogenesis of this disease. Our aim was to evaluate blood flow dysregulation and its relation to leukoaraiosis. MATERIALS AND METHODS Cerebrovascular reactivity, the change in the blood oxygen level-dependent 3T MR imaging signal in response to a consistently applied step change in the arterial partial pressure of carbon dioxide, was measured in white matter hyperintensities and their contralateral spatially homologous normal-appearing white matter in 75 older subjects (age range, 50-91 years; 40 men) with leukoaraiosis. Additional quantitative evaluation of regions of leukoaraiosis was performed by using diffusion (n = 75), quantitative T2 (n = 54), and DSC perfusion MRI metrics (n = 25). RESULTS When we compared white matter hyperintensities with contralateral normal-appearing white matter, cerebrovascular reactivity was lower by a mean of 61.2% ± 22.6%, fractional anisotropy was lower by 44.9 % ± 6.9%, and CBF was lower by 10.9% ± 11.9%. T2 was higher by 61.7% ± 13.5%, mean diffusivity was higher by 59.0% ± 11.7%, time-to-maximum was higher by 44.4% ± 30.4%, and TTP was higher by 6.8% ± 5.8% (all P < .01). Cerebral blood volume was lower in white matter hyperintensities compared with contralateral normal-appearing white matter by 10.2% ± 15.0% (P = .03). CONCLUSIONS Not only were resting blood flow metrics abnormal in leukoaraiosis but there is also evidence of reduced cerebrovascular reactivity in these areas. Studies have shown that reduced cerebrovascular reactivity is more sensitive than resting blood flow parameters for assessing vascular insufficiency. Future work is needed to examine the sensitivity of resting-versus-dynamic blood flow measures for investigating the pathogenesis of leukoaraiosis.
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Affiliation(s)
- K Sam
- From the Departments of Physiology (K.S., J.D., J.A.F.).,Division of Neuroradiology (K.S., A.P.C., J.P., J.C., O.S., D.M.M., D.J.M.), Joint Department of Medical Imaging, University Health Network, Toronto, Ontario, Canada
| | - A P Crawley
- Medical Imaging (A.P.C., D.J.M.), University of Toronto, Toronto, Ontario, Canada.,Division of Neuroradiology (K.S., A.P.C., J.P., J.C., O.S., D.M.M., D.J.M.), Joint Department of Medical Imaging, University Health Network, Toronto, Ontario, Canada
| | - J Poublanc
- Division of Neuroradiology (K.S., A.P.C., J.P., J.C., O.S., D.M.M., D.J.M.), Joint Department of Medical Imaging, University Health Network, Toronto, Ontario, Canada
| | - J Conklin
- Division of Neuroradiology (K.S., A.P.C., J.P., J.C., O.S., D.M.M., D.J.M.), Joint Department of Medical Imaging, University Health Network, Toronto, Ontario, Canada
| | - O Sobczyk
- Division of Neuroradiology (K.S., A.P.C., J.P., J.C., O.S., D.M.M., D.J.M.), Joint Department of Medical Imaging, University Health Network, Toronto, Ontario, Canada
| | - D M Mandell
- Division of Neuroradiology (K.S., A.P.C., J.P., J.C., O.S., D.M.M., D.J.M.), Joint Department of Medical Imaging, University Health Network, Toronto, Ontario, Canada
| | - J Duffin
- From the Departments of Physiology (K.S., J.D., J.A.F.).,Department of Anesthesiology (J.D., L.V., J.A.F.), University Health Network and The University of Toronto, Toronto, Ontario, Canada
| | - L Venkatraghavan
- Department of Anesthesiology (J.D., L.V., J.A.F.), University Health Network and The University of Toronto, Toronto, Ontario, Canada
| | - J A Fisher
- From the Departments of Physiology (K.S., J.D., J.A.F.).,Department of Anesthesiology (J.D., L.V., J.A.F.), University Health Network and The University of Toronto, Toronto, Ontario, Canada
| | - S E Black
- L.C. Campbell Cognitive Neurology Research Unit (S.E.B.), Sunnybrook Health Sciences Centre, Toronto, Ontario, Canada
| | - D J Mikulis
- Medical Imaging (A.P.C., D.J.M.), University of Toronto, Toronto, Ontario, Canada .,Division of Neuroradiology (K.S., A.P.C., J.P., J.C., O.S., D.M.M., D.J.M.), Joint Department of Medical Imaging, University Health Network, Toronto, Ontario, Canada
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Sobczyk O, Crawley AP, Poublanc J, Sam K, Mandell DM, Mikulis DJ, Duffin J, Fisher JA. Identifying Significant Changes in Cerebrovascular Reactivity to Carbon Dioxide. AJNR Am J Neuroradiol 2016; 37:818-24. [PMID: 26846924 DOI: 10.3174/ajnr.a4679] [Citation(s) in RCA: 33] [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] [Subscribe] [Scholar Register] [Received: 07/22/2015] [Accepted: 10/23/2015] [Indexed: 01/04/2023]
Abstract
BACKGROUND AND PURPOSE Changes in cerebrovascular reactivity can be used to assess disease progression and response to therapy but require discrimination of pathology from normal test-to-test variability. Such variability is due to variations in methodology, technology, and physiology with time. With uniform test conditions, our aim was to determine the test-to-test variability of cerebrovascular reactivity in healthy subjects and in patients with known cerebrovascular disease. MATERIALS AND METHODS Cerebrovascular reactivity was the ratio of the blood oxygen level-dependent MR imaging response divided by the change in carbon dioxide stimulus. Two standardized cerebrovascular reactivity tests were conducted at 3T in 15 healthy men (36.7 ± 16.1 years of age) within a 4-month period and were coregistered into standard space to yield voxelwise mean cerebrovascular reactivity interval difference measures, composing a reference interval difference atlas. Cerebrovascular reactivity interval difference maps were prepared for 11 male patients. For each patient, the test-retest difference of each voxel was scored statistically as z-values of the corresponding voxel mean difference in the reference atlas and then color-coded and superimposed on the anatomic images to create cerebrovascular reactivity interval difference z-maps. RESULTS There were no significant test-to-test differences in cerebrovascular reactivity in either gray or white matter (mean gray matter, P = .431; mean white matter, P = .857; paired t test) in the healthy cohort. The patient cerebrovascular reactivity interval difference z-maps indicated regions where cerebrovascular reactivity increased or decreased and the probability that the changes were significant. CONCLUSIONS Accounting for normal test-to-test differences in cerebrovascular reactivity enables the assessment of significant changes in disease status (stability, progression, or regression) in patients with time.
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Affiliation(s)
- O Sobczyk
- From the Institute of Medical Science (O.S., D.J.M., J.A.F.)
| | - A P Crawley
- Joint Department of Medical Imaging and the Functional Neuroimaging Laboratory (A.P.C., J.P., K.S., D.M.M., D.J.M.)
| | - J Poublanc
- Joint Department of Medical Imaging and the Functional Neuroimaging Laboratory (A.P.C., J.P., K.S., D.M.M., D.J.M.)
| | - K Sam
- Department of Physiology (K.S., J.D., J.A.F.), University of Toronto, Toronto, Canada Joint Department of Medical Imaging and the Functional Neuroimaging Laboratory (A.P.C., J.P., K.S., D.M.M., D.J.M.)
| | - D M Mandell
- Joint Department of Medical Imaging and the Functional Neuroimaging Laboratory (A.P.C., J.P., K.S., D.M.M., D.J.M.)
| | - D J Mikulis
- From the Institute of Medical Science (O.S., D.J.M., J.A.F.) Joint Department of Medical Imaging and the Functional Neuroimaging Laboratory (A.P.C., J.P., K.S., D.M.M., D.J.M.)
| | - J Duffin
- Department of Physiology (K.S., J.D., J.A.F.), University of Toronto, Toronto, Canada Department of Anaesthesia and Pain Management (J.D., J.A.F.), University Health Network, Toronto, Canada
| | - J A Fisher
- From the Institute of Medical Science (O.S., D.J.M., J.A.F.) Department of Physiology (K.S., J.D., J.A.F.), University of Toronto, Toronto, Canada Department of Anaesthesia and Pain Management (J.D., J.A.F.), University Health Network, Toronto, Canada
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Hou HM, Sam K, Hägg U, Rabie ABM, Bendeus M, Yam LYC, Ip MS. Long-term dentofacial changes in Chinese obstructive sleep apnea patients after treatment with a mandibular advancement device. Angle Orthod 2006; 76:432-40. [PMID: 16637723 DOI: 10.1043/0003-3219(2006)076[0432:ldcico]2.0.co;2] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
The objective of this study was to evaluate long-term dentofacial changes in Chinese obstructive sleep apnea (OSA) patients treated with a mandibular advancement device (MAD). Lateral cephalograms in natural head posture were obtained from 67 consecutive OSA patients (mean age = 46.9 +/- 8.9 years) treated with an MAD. The cephalograms were obtained at start of treatment (T0), after 1 year (T1), 2 years (T2), and 3 years (T3) of treatment. The lateral cephalograms were digitized twice, and the average of two readings was used for statistical analyses. Small, but statistically significant changes occurred in some dentofacial variables. The lower anterior facial height steadily increased during the observation period, and this increase was significant for the T0-T1 and T1-T2 periods and marginally significant for the T2-T3 period. A significant increase in the mandibular plane angle was observed during the T0-T1 and T2-T3 periods only. Significant reductions in the overjet and overbite were observed for the T0-T1 period but not thereafter. Statistically significant dentofacial changes were observed in this study, but they were of small magnitude. The overjet and overbite changes observed mainly occurred at the initial stage of treatment.
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Affiliation(s)
- H M Hou
- Faculty of Dentistry, The University of Hong Kong, Prince Philip Dental Hospital, 34 Hospital Road, Hong Kong SAR, People's Republic of China
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10
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Sam K, Lam B, Ooi CG, Cooke M, Ip MS. Effect of a non-adjustable oral appliance on upper airway morphology in obstructive sleep apnoea. Respir Med 2005; 100:897-902. [PMID: 16219453 DOI: 10.1016/j.rmed.2005.08.019] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/04/2004] [Revised: 06/01/2005] [Accepted: 08/10/2005] [Indexed: 11/28/2022]
Abstract
BACKGROUND To evaluate the effect of oral appliance (OA) on upper airway morphology and its relationship with treatment response in subjects with obstructive sleep apnoea (OSA). METHODS Symptomatic OSA subjects were recruited. Non-adjustable OA was custom made. Variables examined at baseline and while wearing the device at 2 months included polysomnographic data, computed tomographic measurements of upper airway cross sectional area at level of velopharynx (VA) and hypopharynx (HA), upper airway volume, and cephalometric parameters. Treatment outcome was based on post-treatment apnoea-hypopnoea index (AHI). RESULTS Forty patients were recruited and 23 (7 women) completed the study. They were middle-aged (49, 40-58 years) (median, interquartile range) and overweight (BMI 26, 23.3-29.5 kg/m2), with moderate OSA (AHI 26.4, 14.1-36). The overall post treatment AHI was 8.4 (2.4-12.5), with 14 (61%) patients showing good response (AHI<10), and the other 9 patients showing moderate response (>50% reduction in AHI but still 10). OA decreased the cross-sectional area of the HA (P=0.046), showed a trend of decreasing the ratio of cross-sectional area of the HA to cross-sectional area of the VA (P=0.053) and significantly increased the overall upper airway volume (P=0.006, n=11). No significant relationship between upper airway parameters and treatment outcome was identified. CONCLUSIONS OA altered upper airway morphometry towards a profile consistent with decreased propensity to collapse, which may thus have contributed to improvement of OSA.
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Affiliation(s)
- K Sam
- Orthodontics, Faculty of Dentistry, University of Hong Kong, Hong Kong SAR, China
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Affiliation(s)
- C Xin
- School of Mathematical Sciences, Peking University.
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12
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Sam K, Rabie AB, King NM. Orthodontic intrusion of periodontally involved teeth. J Clin Orthod 2001; 35:325-30. [PMID: 11475543] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/20/2023]
Affiliation(s)
- K Sam
- Faculty of Dentistry, University of Hong Kong, Prince Philip Dental Hospital, 34 Hospital Road, Hong Kong
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Sam K, Labrie F, Poirier D. N-Butyl-N-methyl-11-(3'-hydroxy-21', 17'-carbolactone-19'-nor-17'alpha-pregna-1',3', 5'(10')-trien-7'alpha-yl)-undecanamide: an inhibitor of type 2 17beta-hydroxysteroid dehydrogenase that does not have oestrogenic or androgenic activity. Eur J Med Chem 2000; 35:217-25. [PMID: 10758283 DOI: 10.1016/s0223-5234(00)00124-0] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
It is well known that 17beta-hydroxysteroid dehydrogenases (17beta-HSDs) play a key role in the formation and inactivation, from circulating precursors, of several active androgens and oestrogens. These enzymes can thus regulate tumoural cell proliferation in androgen- and oestrogen-dependent cancers. Recently, we discovered that adding a spiro-gamma-lactone to the oestradiol nucleus results in a novel inhibitor of type 2 17beta-HSD, an enzyme that catalyses the interconversions between 4-androstene-3,17-dione and testosterone, and between oestrone and oestradiol. This finding motivated our introducing the spiro-gamma-lactone moiety onto an anti-oestrogenic nucleus. The N-butyl-N-methyl-11-(3'-hydroxy-21', 17'-carbolactone-19'-nor-17'alpha-pregna-1',3', 5'(10')-trien-7'alpha-yl)-undecanamide (4) was then efficiently synthesized and its biological activity was assessed in vitro. Despite the presence of a bulky alkylamide side chain, the spiro-gamma-lactone function conserved its ability to inhibit type 2 17beta-HSD (IC(50) = 0.35 and 0.25 microM, with and without side chain, respectively). Furthermore, the selective inhibition by lactone 4 toward type 2 17beta-HSD (microsomal fraction of human placenta) was demonstrated by the absence of inhibitory activity toward type 1 17beta-HSD (cytosolic fraction of human placenta). Cell proliferation assays indicated that compound 4 had no oestrogenic activity but did show anti-oestrogenic activity on ER(+) cell line ZR-75-1. No androgenic activity could be detected when assayed on the AR(+) cell line Shionogi either. Based on these facts, we report the synthesis of a new steroidal derivative, one that inhibits type 2 17beta-HSD while possessing anti-oestrogenic activity.
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Affiliation(s)
- K Sam
- Medicinal Chemistry Division, Laboratory of Molecular Endocrinology, Laval University Medical Research Center, Centre hospitalier universitaire de Québec and Laval University, 2705 Laurier Boulevard, Québec, Canada
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