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Howard K, Garvey G, Anderson K, Dickson M, Viney R, Ratcliffe J, Howell M, Gall A, Cunningham J, Whop LJ, Cass A, Jaure A, Mulhern B. Development of the What Matters 2 Adults (WM2A) wellbeing measure for Aboriginal and Torres Strait Islander adults. Soc Sci Med 2024; 347:116694. [PMID: 38569315 DOI: 10.1016/j.socscimed.2024.116694] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2023] [Revised: 01/30/2024] [Accepted: 02/12/2024] [Indexed: 04/05/2024]
Abstract
PURPOSE As wellbeing is culturally bound, wellbeing measures for Aboriginal and Torres Strait Islander peoples must be culturally relevant and grounded in Aboriginal and Torres Strait Islander values and preferences. We describe the development of a nationally-relevant and culturally grounded wellbeing measure for Aboriginal and Torres Strait Islander adults: the What Matters to Adults (WM2A) measure. METHODS We used a mixed methods approach to measure development, combining Indigenist methodologies and psychometric methods. Candidate items were derived through a large national qualitative study. Think-aloud interviews (n = 17) were conducted to assess comprehension, acceptability, and wording of candidate items. Two national surveys collected data on the item pool (n = 312, n = 354). Items were analysed using exploratory factor analysis (EFA), and item response theory (IRT) to test dimensionality, local dependence and item fit. A Collaborative Yarning approach ensured Aboriginal and Torres Strait Islander voices were privileged throughout. RESULTS Fifty candidate items were developed, refined, and tested. Using EFA, an eight factor model was developed. All items met pre-specified thresholds for maximum endorsement frequencies, and floor and ceiling effects; no item redundancy was identified. Ten items did not meet thresholds for aggregate adjacent endorsement frequencies. During Collaborative Yarning, six items were removed based on low factor loadings (<0.4) and twelve due to conceptual overlap, high correlations with other items, endorsement frequencies, and/or low IRT item level information. Several items were retained for content validity. The final measure includes 32 items across 10 domains (Balance & control; Hope & resilience; Caring for others; Culture & Country; Spirit & identity; Feeling valued; Connection with others; Access; Racism & worries; Pride & strength). CONCLUSIONS The unique combination of Indigenist and psychometric methodologies to develop WM2A ensures a culturally and psychometrically robust measure, relevant across a range of settings and applications.
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Affiliation(s)
- K Howard
- Menzies Centre for Health Policy and Economics, Faculty of Medicine and Health, University of Sydney, NSW, 2006, Australia; Sydney School of Public Health, Faculty of Medicine and Health, University of Sydney, NSW, 2006, Australia.
| | - G Garvey
- The First Nations Cancer & Wellbeing Research Team, The School of Public Health, Faculty of Medicine, The University of Queensland, Brisbane Qld 4072, Australia
| | - K Anderson
- The First Nations Cancer & Wellbeing Research Team, The School of Public Health, Faculty of Medicine, The University of Queensland, Brisbane Qld 4072, Australia
| | - M Dickson
- Sydney School of Public Health, Faculty of Medicine and Health, University of Sydney, NSW, 2006, Australia; The Poche Centre for Indigenous Health, Faculty of Medicine and Health, University of Sydney, NSW, 2006, Australia
| | - R Viney
- The Centre for Health Economics Research and Evaluation (CHERE), University of Technology Sydney, Ultimo, NSW, 2007, Australia
| | - J Ratcliffe
- Caring Futures Institute, College of Nursing and Health Sciences, Flinders University, Adelaide, SA, 5001, Australia
| | - M Howell
- Menzies Centre for Health Policy and Economics, Faculty of Medicine and Health, University of Sydney, NSW, 2006, Australia; Sydney School of Public Health, Faculty of Medicine and Health, University of Sydney, NSW, 2006, Australia
| | - A Gall
- The First Nations Cancer & Wellbeing Research Team, The School of Public Health, Faculty of Medicine, The University of Queensland, Brisbane Qld 4072, Australia
| | - J Cunningham
- Menzies School of Health Research, Charles Darwin University, Darwin NT, Australia
| | - L J Whop
- National Centre for Epidemiology and Population Health, College of Health and Medicine, Australian National University, Canberra, ACT, 2600, Australia
| | - A Cass
- Menzies School of Health Research, Charles Darwin University, Darwin NT, Australia
| | - A Jaure
- Sydney School of Public Health, Faculty of Medicine and Health, University of Sydney, NSW, 2006, Australia
| | - B Mulhern
- The Centre for Health Economics Research and Evaluation (CHERE), University of Technology Sydney, Ultimo, NSW, 2007, Australia
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2
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Messant M, Hani U, Hennebelle T, Guérard F, Gakière B, Gall A, Thomine S, Krieger-Liszkay A. Manganese concentration affects chloroplast structure and the photosynthetic apparatus in Marchantia polymorpha. Plant Physiol 2023; 192:356-369. [PMID: 36722179 DOI: 10.1093/plphys/kiad052] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/09/2022] [Revised: 12/06/2022] [Accepted: 12/06/2022] [Indexed: 05/03/2023]
Abstract
Manganese (Mn) is an essential metal for plant growth. The most important Mn-containing enzyme is the Mn4CaO5 cluster that catalyzes water oxidation in photosystem II (PSII). Mn deficiency primarily affects photosynthesis, whereas Mn excess is generally toxic. Here, we studied Mn excess and deficiency in the liverwort Marchantia polymorpha, an emerging model ideally suited for analysis of metal stress since it accumulates rapidly toxic substances due to the absence of well-developed vascular and radicular systems and a reduced cuticle. We established growth conditions for Mn excess and deficiency and analyzed the metal content in thalli and isolated chloroplasts. In vivo super-resolution fluorescence microscopy and transmission electron microscopy revealed changes in the organization of the thylakoid membrane under Mn excess and deficiency. Both Mn excess and Mn deficiency increased the stacking of the thylakoid membrane. We investigated photosynthetic performance by measuring chlorophyll fluorescence at room temperature and 77 K, measuring P700 absorbance, and studying the susceptibility of thalli to photoinhibition. Nonoptimal Mn concentrations changed the ratio of PSI to PSII. Upon Mn deficiency, higher non-photochemical quenching was observed, electron donation to PSI was favored, and PSII was less susceptible to photoinhibition. Mn deficiency seemed to favor cyclic electron flow around PSI, thereby protecting PSII in high light. The results presented here suggest an important role of Mn in the organization of the thylakoid membrane and photosynthetic electron transport.
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Affiliation(s)
- Marine Messant
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Saclay, 91198 Gif-sur-Yvette cedex, France
| | - Umama Hani
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Saclay, 91198 Gif-sur-Yvette cedex, France
| | - Thaïs Hennebelle
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Saclay, 91198 Gif-sur-Yvette cedex, France
| | - Florence Guérard
- Institute of Plant Sciences Paris-Saclay, CNRS, Université Paris-Sud, Institut National de la Recherche Agronomique, Université d'Evry, Université Paris-Diderot, Université Paris-Saclay, 91405 Orsay Cedex, France
| | - Bertrand Gakière
- Institute of Plant Sciences Paris-Saclay, CNRS, Université Paris-Sud, Institut National de la Recherche Agronomique, Université d'Evry, Université Paris-Diderot, Université Paris-Saclay, 91405 Orsay Cedex, France
| | - Andrew Gall
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Saclay, 91198 Gif-sur-Yvette cedex, France
| | - Sébastien Thomine
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Saclay, 91198 Gif-sur-Yvette cedex, France
| | - Anja Krieger-Liszkay
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Saclay, 91198 Gif-sur-Yvette cedex, France
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Bruno VD, Sammut E, Gall A, Baz-Lopez D, Ascione R, Johnson TW. Quantitative evaluation of coronary artery occlusion by 3D coronary volume reconstruction in a large animal model of acute myocardial infarction. Eur Heart J 2021. [DOI: 10.1093/eurheartj/ehab724.3257] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Abstract
Background
Large animal models of acute myocardial infarction (MI) offer an important platform to test novel therapies. Consistency of infarct size between animals is critical to ensure an accurate assessment of therapies against control. However, anatomical variation challenges the ability to achieve a consistent infarct size and care must be taken to respect the principles of the 3Rs through minimisation of interventional fatalities.
Purpose
To standardise the approach of a closed chest model of balloon occlusion-facilitated MI. Novel 3-dimensional quantitative coronary angiography (3DQCA) software has been used retrospectively to identify a correlation between coronary volume occlusion and the extension of the myocardial scar.
Methods
Twenty-four Yorkshire pigs (mean weight 63.1±3 kg) underwent a closed chest MI model via percutaneous occlusion of the mid portion of the left anterior descending artery (LAD) for 60 minutes. The evaluation of the myocardial damage was obtained via cardiac magnetic resonance imaging (CMR) between 24 and 48 hours after the MI model (Acute) and at 4–5 weeks after MI (Chronic). Troponin I was also measured at multiple timepoints. 3DQCA reconstruction (QAngio XA 3D, Medis medical imaging systems NL) was generated from 2 angiographic projections with segmental analysis of all 3 major epicardial vessels including lumen volume, reference diameters, and segment length. The occlusive volume and vessel length was identified through co-registration of balloon position.
Results
At the short term timepoint, a significant correlation was found between the LAD volume occluded and the scar size as percentage of the LV mass (Spearman correlation 0.72, p value <0.01, Fig. 1). Using Youden index analysis we identified a cut-off point of 32.8% of the LAD volume to determine a scar volume >20% (Fig. 2). At chronic phase the correlation between these two variables was not significant, although there was a trend towards significance (p value = 0.06, Cor = 0.54). No significant correlation was found with serum Troponin I.
Conclusions
There is a significant correlation between the LAD volume occluded and the overall scar size in the acute phase and at least 32.8% of the LAD volume should be occluded to determine a scar volume >20% of the entire LV. This indicates that a prospective measure of occluded LAD volume might minimise the intra-experimental variability in studies aiming to reduce infarct size and acute myocardial injury.
Funding Acknowledgement
Type of funding sources: Other. Main funding source(s): This research work was supported by grants awarded to Professor Ascione: the British Heart Foundation (BHF) (BHF IG/14/2/30991, BHF RM/13/2/30158), and the Medical Research Council (MRC) (MRC MR/L012723/1).
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Affiliation(s)
- V D Bruno
- University of Bristol, Bristol, United Kingdom
| | - E Sammut
- University of Bristol, Bristol, United Kingdom
| | - A Gall
- Bristol Heart Institute, Bristol, United Kingdom
| | - D Baz-Lopez
- University of Bristol, Bristol, United Kingdom
| | - R Ascione
- University of Bristol, Bristol, United Kingdom
| | - T W Johnson
- University of Bristol, Bristol, United Kingdom
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Gall A, Diaz A, Garvey G, Anderson K, Lindsay D, Howard K. An exploration of the sociodemographic and health conditions associated with self-rated wellbeing for Aboriginal and Torres Strait Islander adults. BMC Res Notes 2021; 14:386. [PMID: 34600592 PMCID: PMC8487334 DOI: 10.1186/s13104-021-05794-3] [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] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2021] [Accepted: 09/20/2021] [Indexed: 11/21/2022] Open
Abstract
Objective To identify sociodemographic factors and health conditions associated with self-rated wellbeing for Aboriginal and Torres Strait Islander adults. Participants were recruited via investigator networks and an online panel provider with an established nationwide panel of Aboriginal and Torres Strait Islander adults. Those interested were invited to complete a survey that included an assessment of wellbeing using a visual analogue scale. Data was collected from October–November 2019 and August–September 2020. Exploratory analyses were conducted to ascertain factors associated with self-rated wellbeing for Aboriginal and Torres Strait Islander adults. Results Having more than enough money to last until next pay day, full-time employment, completion of grade 12, having a partner, and living with others were significantly associated with higher wellbeing among Aboriginal and Torres Strait Islander adults. A self-reported history of depression, anxiety, other mental health conditions, heart disease, or disability were associated with lower self-rated wellbeing scores. Our findings indicate a need for further investigation among these socioeconomic and patient groups to identify how to improve and support the wellbeing of Aboriginal and Torres Strait Islander adults. Supplementary Information The online version contains supplementary material available at 10.1186/s13104-021-05794-3.
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Affiliation(s)
- A Gall
- Wellbeing and Preventable Chronic Disease Division, Menzies School of Health Research, Charles Darwin University, Casuarina, NT, Australia.
| | - A Diaz
- Wellbeing and Preventable Chronic Disease Division, Menzies School of Health Research, Charles Darwin University, Casuarina, NT, Australia
| | - G Garvey
- Wellbeing and Preventable Chronic Disease Division, Menzies School of Health Research, Charles Darwin University, Casuarina, NT, Australia.,School of Public Health, Faculty of Medicine & Health, University of Sydney, Sydney, NSW, 2006, Australia.,School of Public Health, University of Queensland, Brisbane, Australia
| | - K Anderson
- Wellbeing and Preventable Chronic Disease Division, Menzies School of Health Research, Charles Darwin University, Casuarina, NT, Australia
| | - D Lindsay
- Wellbeing and Preventable Chronic Disease Division, Menzies School of Health Research, Charles Darwin University, Casuarina, NT, Australia
| | - K Howard
- School of Public Health, Faculty of Medicine & Health, University of Sydney, Sydney, NSW, 2006, Australia.,Menzies Centre for Health Policy and Economics, Faculty of Medicine and Health, University of Sydney, Sydney, NSW, 2006, Australia
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5
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Streckaite S, Llansola-Portoles MJ, Pascal AA, Ilioaia C, Gall A, Seki S, Fujii R, Robert B. Pigment structure in the light-harvesting protein of the siphonous green alga Codium fragile. Biochim Biophys Acta Bioenerg 2021; 1862:148384. [PMID: 33545114 DOI: 10.1016/j.bbabio.2021.148384] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 10/13/2020] [Revised: 01/11/2021] [Accepted: 01/21/2021] [Indexed: 11/15/2022]
Abstract
The siphonaxanthin-siphonein-chlorophyll-a/b-binding protein (SCP), a trimeric light-harvesting complex isolated from photosystem II of the siphonous green alga Codium fragile, binds the carotenoid siphonaxanthin (Sx) and/or its ester siphonein in place of lutein, in addition to chlorophylls a/b and neoxanthin. SCP exhibits a higher content of chlorophyll b (Chl-b) than its counterpart in green plants, light-harvesting complex II (LHCII), increasing the relative absorption of blue-green light for photosynthesis. Using low temperature absorption and resonance Raman spectroscopies, we reveal the presence of two non-equivalent Sx molecules in SCP, and assign their absorption peaks at 501 and 535 nm. The red-absorbing Sx population exhibits a significant distortion that is reminiscent of lutein 2 in trimeric LHCII. Unexpected enhancement of the Raman modes of Chls-b in SCP allows an unequivocal description of seven to nine non-equivalent Chls-b, and six distinct Chl-a populations in this protein.
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Affiliation(s)
- Simona Streckaite
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198 Gif-sur-Yvette, France
| | - Manuel J Llansola-Portoles
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198 Gif-sur-Yvette, France
| | - Andrew A Pascal
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198 Gif-sur-Yvette, France
| | - Cristian Ilioaia
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198 Gif-sur-Yvette, France
| | - Andrew Gall
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198 Gif-sur-Yvette, France
| | - Soichiro Seki
- Osaka City University, Graduate School of Science, Sumiyoshi Ku, 3-3-138 Sugimoto, Osaka 5588585, Japan
| | - Ritsuko Fujii
- Osaka City University, Graduate School of Science, Sumiyoshi Ku, 3-3-138 Sugimoto, Osaka 5588585, Japan; Osaka City University, The OCU Research Center for Artificial Photosynthesis, Sumiyoshi Ku, 3-3-138 Sugimoto, Osaka 5588585, Japan
| | - Bruno Robert
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198 Gif-sur-Yvette, France.
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Kendall E, Ehrlich C, Chapman K, Shirota C, Allen G, Gall A, Kek-Pamenter JA, Cocks K, Palipana D. Immediate and Long-Term Implications of the COVID-19 Pandemic for People With Disabilities. Am J Public Health 2020; 110:1774-1779. [PMID: 33058709 PMCID: PMC7661992 DOI: 10.2105/ajph.2020.305890] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/22/2020] [Indexed: 11/04/2022]
Abstract
Some people with disabilities may have greater risk of contracting COVID-19 or experiencing worse outcomes if infected. Although COVID-19 is a genuine threat for people with disabilities, they also fear decisions that might limit lifesaving treatment should they contract the virus.During a pandemic, health systems must manage excess demand for treatment, and governments must enact heavy restrictions on their citizens to prevent transmission. Both actions can have a negative impact on people with disabilities.Ironically, the sociotechnical advances prompted by this pandemic could also revolutionize quality of life and participation for people with disabilities. Preparation for future disasters requires careful consideration.
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Affiliation(s)
- Elizabeth Kendall
- All of the authors are with the Hopkins Centre, Menzies Health Institute Qld, Griffith University, Queensland, Australia
| | - Carolyn Ehrlich
- All of the authors are with the Hopkins Centre, Menzies Health Institute Qld, Griffith University, Queensland, Australia
| | - Kelsey Chapman
- All of the authors are with the Hopkins Centre, Menzies Health Institute Qld, Griffith University, Queensland, Australia
| | - Camila Shirota
- All of the authors are with the Hopkins Centre, Menzies Health Institute Qld, Griffith University, Queensland, Australia
| | - Gary Allen
- All of the authors are with the Hopkins Centre, Menzies Health Institute Qld, Griffith University, Queensland, Australia
| | - Andrew Gall
- All of the authors are with the Hopkins Centre, Menzies Health Institute Qld, Griffith University, Queensland, Australia
| | - Joe-Anne Kek-Pamenter
- All of the authors are with the Hopkins Centre, Menzies Health Institute Qld, Griffith University, Queensland, Australia
| | - Kevin Cocks
- All of the authors are with the Hopkins Centre, Menzies Health Institute Qld, Griffith University, Queensland, Australia
| | - Dinesh Palipana
- All of the authors are with the Hopkins Centre, Menzies Health Institute Qld, Griffith University, Queensland, Australia
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7
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Connolly G, Mora J, Sammut E, Kashyap M, Dastidar A, Gall A, De Silva K, Joshi N, Dorman S, Strange J, Johnson T. How relevant is the ISCHEMIA trial to a rapid access chest pain clinic cohort of patients? Eur Heart J 2020. [DOI: 10.1093/ehjci/ehaa946.1414] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Abstract
Background
The ISCHEMIA trial demonstrated that optimal medical therapy (OMT) is not inferior to an early interventional approach for stable angina. This could significantly impact on clinical practice. This study aimed to check the relevance of the ISCHEMIA trial in a real-world population of patients referred to a tertiary centre with recent onset chest pain (CP).
Methods
In this registry study, electronic notes of all patients assessed in a Rapid Access Chest Pain Clinic (RACPC) within a 12-month period (2018–19) were reviewed. Patients were selected if they met key ISCHEMIA trial inclusion criteria.
Results
2416 patients were assessed, 378 (15.6%) presented with typical anginal CP, 1357 (56.2%) had atypical CP and 681 (28.2%) had non anginal CP.
Of the typical CP group, 158 patients were excluded (91 known CAD, 62 ACS, 2 eGFR <30mL/min, 3 severe LVSD). This resulted in 220 patients, representing 58.2% of the typical chest pain population and 9.1% of all patients seen in RACPC. These patients had a median age of 60 years, 96 (44%) female, 119 (54.1%) had high cholesterol, 44 (20%) had diabetes, 115 (52.3%) had hypertension, 104 (47.3%) had a family history of ischaemic heart disease, and 32 (14.5%) were current smokers.
Of these 220 patients, 48 (21.8%) had a CT coronary angiogram (CTCA) requested as their first line investigation (42 completed) with 1 (2.4%) patients result suggestive of significant left main stem (LMS) disease. 15 (6.8%) patients had stress echocardiography requested as their first line investigation (13 completed), 4 (31%) were positive for inducible ischaemia. 3 (1.4%) patients had stress CMR requested as their first line investigation (2 completed), both were negative. 143 (65%) patients had an invasive coronary angiogram (ICA) requested as their first line investigation (112 completed). 8 patients had severe LMS disease and were referred for surgical opinion. A further 11 patients were referred for surgical opinion due to multivessel disease or aberrant coronary anatomy. In total 24 (21.4%) patients were treated with PCI following ICA as their first line investigation.
All patients were started on medical therapy for presumed CAD with up-titration while awaiting investigations. The median wait time for a CTCA was 55 days compared to 165.5 days for ICA.
Two patients (0.9%) from the cohort of 220 patients died during the follow up period, compared to 2.5% of patients admitted from RACPC with an ACS diagnosis.
Conclusion
Patients present with undifferentiated chest pain, consequently the outcomes of the ISCHEMIA trial must be considered cautiously. Within our cohort of 2416 patients, only 9% of patients met key inclusion criteria of the trial. Ultimately, only 19.5% patients with typical chest pain were revascularised, unlike 80% of patients in the invasive arm of ISCHEMIA. It is unclear how the results of the ISCHEMIA trial will impact on UK practice, but it is clear that OMT plays a central role.
Funding Acknowledgement
Type of funding source: None
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Affiliation(s)
| | - J Mora
- Bristol Heart Institute, Bristol, United Kingdom
| | - E Sammut
- University of Bristol, Bristol, United Kingdom
| | - M Kashyap
- Bristol Heart Institute, Bristol, United Kingdom
| | - A Dastidar
- Bristol Heart Institute, Bristol, United Kingdom
| | - A Gall
- Bristol Heart Institute, Bristol, United Kingdom
| | - K De Silva
- Bristol Heart Institute, Bristol, United Kingdom
| | - N Joshi
- Bristol Heart Institute, Bristol, United Kingdom
| | - S Dorman
- Bristol Heart Institute, Bristol, United Kingdom
| | - J Strange
- Bristol Heart Institute, Bristol, United Kingdom
| | - T Johnson
- Bristol Heart Institute, Bristol, United Kingdom
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8
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Chenebault C, Diaz-Santos E, Kammerscheit X, Görgen S, Ilioaia C, Streckaite S, Gall A, Robert B, Marcon E, Buisson DA, Benzerara K, Sassi JF, Cassier-Chauvat C, Chauvat F. A Genetic Toolbox for the New Model Cyanobacterium Cyanothece PCC 7425: A Case Study for the Photosynthetic Production of Limonene. Front Microbiol 2020; 11:586601. [PMID: 33042102 PMCID: PMC7530172 DOI: 10.3389/fmicb.2020.586601] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [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: 07/23/2020] [Accepted: 08/31/2020] [Indexed: 12/17/2022] Open
Abstract
Cyanobacteria, the largest phylum of prokaryotes, perform oxygenic photosynthesis and are regarded as the ancestors of the plant chloroplast and the purveyors of the oxygen and biomass that shaped the biosphere. Nowadays, cyanobacteria are attracting a growing interest in being able to use solar energy, H2O, CO2 and minerals to produce biotechnologically interesting chemicals. This often requires the introduction and expression of heterologous genes encoding the enzymes that are not present in natural cyanobacteria. However, only a handful of model strains with a well-established genetic system are being studied so far, leaving the vast biodiversity of cyanobacteria poorly understood and exploited. In this study, we focused on the robust unicellular cyanobacterium Cyanothece PCC 7425 that has many interesting attributes, such as large cell size; capacity to fix atmospheric nitrogen (under anaerobiosis) and to grow not only on nitrate but also on urea (a frequent pollutant) as the sole nitrogen source; capacity to form CO2-sequestrating intracellular calcium carbonate granules and to produce various biotechnologically interesting products. We demonstrate for the first time that RSF1010-derived plasmid vectors can be used for promoter analysis, as well as constitutive or temperature-controlled overproduction of proteins and analysis of their sub-cellular localization in Cyanothece PCC 7425. These findings are important because no gene manipulation system had been developed for Cyanothece PCC 7425, yet, handicapping its potential to serve as a model host. Furthermore, using this toolbox, we engineered Cyanothece PCC 7425 to produce the high-value terpene, limonene which has applications in biofuels, bioplastics, cosmetics, food and pharmaceutical industries. This is the first report of the engineering of a Cyanothece strain for the production of a chemical and the first demonstration that terpene can be produced by an engineered cyanobacterium growing on urea as the sole nitrogen source.
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Affiliation(s)
- Célia Chenebault
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), Gif-sur-Yvette, France
| | - Encarnación Diaz-Santos
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), Gif-sur-Yvette, France
| | - Xavier Kammerscheit
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), Gif-sur-Yvette, France
| | - Sigrid Görgen
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), Gif-sur-Yvette, France.,Sorbonne Université, Muséum National d'Histoire Naturelle, UMR CNRS 7590, Institut de Minéralogie, de Physique des Matériaux et de Cosmochimie, IMPMC, Paris, France
| | - Cristian Ilioaia
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), Gif-sur-Yvette, France
| | - Simona Streckaite
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), Gif-sur-Yvette, France
| | - Andrew Gall
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), Gif-sur-Yvette, France
| | - Bruno Robert
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), Gif-sur-Yvette, France
| | - Elodie Marcon
- Université Paris-Saclay, Service de Chimie Bio-organique et Marquage (SCBM), CEA/DRF/JOLIOT, Gif-sur-Yvette, France
| | - David-Alexandre Buisson
- Université Paris-Saclay, Service de Chimie Bio-organique et Marquage (SCBM), CEA/DRF/JOLIOT, Gif-sur-Yvette, France
| | - Karim Benzerara
- Sorbonne Université, Muséum National d'Histoire Naturelle, UMR CNRS 7590, Institut de Minéralogie, de Physique des Matériaux et de Cosmochimie, IMPMC, Paris, France
| | - Jean-François Sassi
- Commissariat à l'Énergie Atomique et aux Énergies Alternatives (CEA), Centre de Cadarache, Saint-Paul-lez-Durance, France
| | - Corinne Cassier-Chauvat
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), Gif-sur-Yvette, France
| | - Franck Chauvat
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), Gif-sur-Yvette, France
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Gall A, Anderson K, Adams J, Matthews V, Garvey G. An exploration of healthcare providers' experiences and perspectives of Traditional and complementary medicine usage and disclosure by Indigenous cancer patients. Altern Ther Health Med 2019; 19:259. [PMID: 31533782 PMCID: PMC6751784 DOI: 10.1186/s12906-019-2665-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2018] [Accepted: 08/30/2019] [Indexed: 11/10/2022]
Abstract
Background Traditional and complementary medicines (T&CM) are any form of medicine, practice, treatment, product, technology, knowledge system or ceremony outside of conventional medical practice that aims to prevent and/or treat illness and/or promote well-being. Alongside conventional cancer treatments, T&CM usage is increasing; with 19% of indigenous Australians with cancer reporting using T&CM. There is limited evidence surrounding T&CM use and disclosure by indigenous patients. Our aim was to explore healthcare providers’ views about usage, disclosure/non-disclosure of T&CM by Indigenous cancer patients. Methods Semi-structured, in-depth interviews with 18 healthcare providers, including three indigenous providers, at a large urban hospital providing care to Indigenous cancer patients were conducted to explore providers’ experiences and attitudes towards T&CM use by Indigenous cancer patients. An interpretive phenomenological approach was used to thematically analyse the data. Results Analysis revealed six themes: concern about risk; no ‘real’ benefits; perception of T&CM and conventional medicine as antithetical; barriers to disclosure; ‘patients’ choice’ a double-edged sword; and providers’ lack of knowledge about T&CM. Healthcare providers perceived discord between T&CM and conventional medicine. Most lacked knowledge of T&CM, and had concerns around negative-interactions with conventional treatments. They considered T&CM outside their role, citing this as reasoning for their lack of knowledge. Indigenous healthcare providers had greater understanding and openness towards T&CM. Conclusions Given the potential usage of T&CM by Indigenous cancer patients, providers need a more comprehensive understanding of T&CM in order to inform discussion and facilitate effective disclosure on this topic. If indigenous Australians with cancer feel that cancer care providers are unreceptive to discussing T&CM, patient care risks being compromised; particularly given the potential for negative interactions between T&CM and conventional cancer treatments. Fostering health care interactions where indigenous patients feel comfortable to discuss T&CM usage should be a priority for all cancer care services.
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Llansola-Portoles MJ, Li F, Xu P, Streckaite S, Ilioaia C, Yang C, Gall A, Pascal AA, Croce R, Robert B. Tuning antenna function through hydrogen bonds to chlorophyll a. Biochim Biophys Acta Bioenerg 2019; 1861:148078. [PMID: 31476286 DOI: 10.1016/j.bbabio.2019.148078] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2019] [Revised: 08/27/2019] [Accepted: 08/28/2019] [Indexed: 01/08/2023]
Abstract
We describe a molecular mechanism tuning the functional properties of chlorophyll a (Chl-a) molecules in photosynthetic antenna proteins. Light-harvesting complexes from photosystem II in higher plants - specifically LHCII purified with α- or β-dodecyl-maltoside, along with CP29 - were probed by low-temperature absorption and resonance Raman spectroscopies. We show that hydrogen bonding to the conjugated keto carbonyl group of protein-bound Chl-a tunes the energy of its Soret and Qy absorption transitions, inducing red-shifts that are proportional to the strength of the hydrogen bond involved. Chls-a with non-H-bonded keto C131 groups exhibit the blue-most absorption bands, while both transitions are progressively red-shifted with increasing hydrogen-bonding strength - by up 382 & 605 cm-1 in the Qy and Soret band, respectively. These hydrogen bonds thus tune the site energy of Chl-a in light-harvesting proteins, determining (at least in part) the cascade of energy transfer events in these complexes.
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Affiliation(s)
- Manuel J Llansola-Portoles
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Saclay, F-91198 Gif-sur-Yvette cedex, France
| | - Fei Li
- Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China
| | - Pengqi Xu
- Department of Physics and Astronomy, Faculty of Sciences, VU University Amsterdam, De Boelelaan 1081, 1081 HV Amsterdam, the Netherlands
| | - Simona Streckaite
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Saclay, F-91198 Gif-sur-Yvette cedex, France
| | - Cristian Ilioaia
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Saclay, F-91198 Gif-sur-Yvette cedex, France
| | - Chunhong Yang
- Key Laboratory of Photobiology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, PR China
| | - Andrew Gall
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Saclay, F-91198 Gif-sur-Yvette cedex, France
| | - Andrew A Pascal
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Saclay, F-91198 Gif-sur-Yvette cedex, France.
| | - Roberta Croce
- Department of Physics and Astronomy, Faculty of Sciences, VU University Amsterdam, De Boelelaan 1081, 1081 HV Amsterdam, the Netherlands
| | - Bruno Robert
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Saclay, F-91198 Gif-sur-Yvette cedex, France.
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Gall A, Anderson K, Diaz A, Matthews V, Adams J, Taylor T, Garvey G. Exploring traditional and complementary medicine use by Indigenous Australian women undergoing gynaecological cancer investigations. Complement Ther Clin Pract 2019; 36:88-93. [PMID: 31383451 DOI: 10.1016/j.ctcp.2019.06.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [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: 03/19/2019] [Revised: 05/14/2019] [Accepted: 06/12/2019] [Indexed: 01/15/2023]
Abstract
BACKGROUND Indigenous Australian women experience worse gynaecological cancer outcomes than non-Indigenous women. While traditional and complementary medicine (T&CM) is increasingly used by cancer patients alongside conventional treatments, little is known about T&CM use by Indigenous women. This study aimed to explore the beliefs, attitudes and experiences related to T&CM use and disclosure among Indigenous women undergoing gynaecological cancer investigations. METHODS A mixed-methods design explored T&CM use among Indigenous women who presented for gynaecological cancer investigation at an urban Queensland hospital (September 2016 and January 2018). RESULTS Fourteen women participated. The reported use (86%) and perceived value of T&CM was high among the participants, however, women reported major challenges in communicating with healthcare providers about T&CM, commonly associated with trust and rapport. CONCLUSIONS These findings highlight the need for strategies to facilitate culturally-appropriate doctor-patient communication around T&CM to foster trust and transparency in gynaecological cancer care for Indigenous women.
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Affiliation(s)
- A Gall
- Menzies School of Health Research, Charles Darwin University, Darwin, Australia.
| | - K Anderson
- Menzies School of Health Research, Charles Darwin University, Darwin, Australia.
| | - A Diaz
- Menzies School of Health Research, Charles Darwin University, Darwin, Australia.
| | - V Matthews
- The University of Sydney, University Centre for Rural Health, Lismore, Australia.
| | - J Adams
- University of Technology Sydney, Ultimo, Australia.
| | - T Taylor
- Endeavour College of Natural Health, Brisbane, Australia.
| | - G Garvey
- Menzies School of Health Research, Charles Darwin University, Darwin, Australia.
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Warner N, Ikkos G, Gall A. Spinal cord injury rehabilitation and mental health, SCReaM. Spinal Cord 2016; 55:307-313. [DOI: 10.1038/sc.2016.107] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2015] [Revised: 05/28/2016] [Accepted: 06/05/2016] [Indexed: 11/09/2022]
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Gall A, Ilioaia C, Krüger TPJ, Novoderezhkin VI, Robert B, van Grondelle R. Conformational switching in a light-harvesting protein as followed by single-molecule spectroscopy. Biophys J 2016; 108:2713-20. [PMID: 26039172 PMCID: PMC4457476 DOI: 10.1016/j.bpj.2015.04.017] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2014] [Revised: 04/07/2015] [Accepted: 04/14/2015] [Indexed: 12/02/2022] Open
Abstract
Among the ultimate goals of protein physics, the complete, experimental description of the energy paths leading to protein conformational changes remains a challenge. Single protein fluorescence spectroscopy constitutes an approach of choice for addressing protein dynamics, and, among naturally fluorescing proteins, light-harvesting (LH) proteins from purple bacteria constitute an ideal object for such a study. LHs bind bacteriochlorophyll a molecules, which confer on them a high intrinsic fluorescence yield. Moreover, the electronic properties of these pigment-proteins result from the strong excitonic coupling between their bound bacteriochlorophyll a molecules in combination with the large energetic disorder due to slow fluctuations in their structure. As a result, the position and probability of their fluorescence transition delicately depends on the precise realization of the disorder of the set of bound pigments, which is governed by the LH protein dynamics. Analysis of these parameters using time-resolved single-molecule fluorescence spectroscopy thus yields direct access to the protein dynamics. Applying this technique to the LH2 protein from Rhodovulum (Rdv.) sulfidophilum, the structure—and consequently the fluorescence properties—of which depends on pH, allowed us to follow a single protein, pH-induced, reversible, conformational transition. Hence, for the first time, to our knowledge, a protein transition can be visualized through changes in the electronic structure of the intrinsic cofactors, at a level of a single LH protein, which opens a new, to our knowledge, route for understanding the changes in energy landscape that underlie protein function and adaptation to the needs of living organisms.
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Affiliation(s)
- Andrew Gall
- CEA, Institute of Biology and Technology of Saclay, Gif-sur-Yvette, France; Institute for Integrative Biology of the Cell, Université Paris Saclay, CEA, CNRS, Université Paris Sud, CEA-Saclay, Gif sur Yvette, France.
| | - Cristian Ilioaia
- CEA, Institute of Biology and Technology of Saclay, Gif-sur-Yvette, France; Department of Physics and Astronomy, Faculty of Sciences, VU University Amsterdam, Amsterdam, The Netherlands; Institute for Integrative Biology of the Cell, Université Paris Saclay, CEA, CNRS, Université Paris Sud, CEA-Saclay, Gif sur Yvette, France
| | - Tjaart P J Krüger
- Department of Physics and Astronomy, Faculty of Sciences, VU University Amsterdam, Amsterdam, The Netherlands; Department of Physics, University of Pretoria, Pretoria, South Africa
| | - Vladimir I Novoderezhkin
- Department of Physics and Astronomy, Faculty of Sciences, VU University Amsterdam, Amsterdam, The Netherlands; A. N. Belozersky Institute of Physico-Chemical Biology, Moscow State University, Moscow, Russia
| | - Bruno Robert
- CEA, Institute of Biology and Technology of Saclay, Gif-sur-Yvette, France; Department of Physics and Astronomy, Faculty of Sciences, VU University Amsterdam, Amsterdam, The Netherlands; Institute for Integrative Biology of the Cell, Université Paris Saclay, CEA, CNRS, Université Paris Sud, CEA-Saclay, Gif sur Yvette, France
| | - Rienk van Grondelle
- Department of Physics and Astronomy, Faculty of Sciences, VU University Amsterdam, Amsterdam, The Netherlands.
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Vásquez N, Knight SL, Susser J, Gall A, Ellaway PH, Craggs MD. Pelvic floor muscle training in spinal cord injury and its impact on neurogenic detrusor over-activity and incontinence. Spinal Cord 2015; 53:887-9. [DOI: 10.1038/sc.2015.121] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2015] [Revised: 05/09/2015] [Accepted: 05/29/2015] [Indexed: 11/09/2022]
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Valéry C, Deville-Foillard S, Lefebvre C, Taberner N, Legrand P, Meneau F, Meriadec C, Delvaux C, Bizien T, Kasotakis E, Lopez-Iglesias C, Gall A, Bressanelli S, Le Du MH, Paternostre M, Artzner F. Atomic view of the histidine environment stabilizing higher-pH conformations of pH-dependent proteins. Nat Commun 2015; 6:7771. [PMID: 26190377 PMCID: PMC4518280 DOI: 10.1038/ncomms8771] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2015] [Accepted: 06/09/2015] [Indexed: 11/17/2022] Open
Abstract
External stimuli are powerful tools that naturally control protein assemblies and functions. For example, during viral entry and exit changes in pH are known to trigger large protein conformational changes. However, the molecular features stabilizing the higher pH structures remain unclear. Here we elucidate the conformational change of a self-assembling peptide that forms either small or large nanotubes dependent on the pH. The sub-angstrom high-pH peptide structure reveals a globular conformation stabilized through a strong histidine-serine H-bond and a tight histidine-aromatic packing. Lowering the pH induces histidine protonation, disrupts these interactions and triggers a large change to an extended β-sheet-based conformation. Re-visiting available structures of proteins with pH-dependent conformations reveals both histidine-containing aromatic pockets and histidine-serine proximity as key motifs in higher pH structures. The mechanism discovered in this study may thus be generally used by pH-dependent proteins and opens new prospects in the field of nanomaterials. In biological systems, large pH-induced conformational changes can be observed in certain proteins, a phenomenon poorly understood at the molecular level. Here the authors describe a peptide with the ability to self-organize into either small or large nanotubes in a pH-dependent manner and detail the mechanism driving the transition.
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Affiliation(s)
- Céline Valéry
- 1] Biomolecular Interaction Centre, School of Biological Sciences, University of Canterbury, 8140 Christchurch, New zealand [2] Ipsen, 5 Avenue du Canada, 91940 Les Ulis, France
| | - Stéphanie Deville-Foillard
- 1] Ipsen, 5 Avenue du Canada, 91940 Les Ulis, France [2] CEA, Institute of Biology and Technologies of Saclay, 91191 CEA-Saclay, France [3] Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Sud, 91191 CEA-Saclay, Gif sur Yvette, France
| | - Christelle Lefebvre
- CNRS, UMR 6251, Institut de Physique de Rennes, 263 av. Général Leclerc, Université Rennes I, 35042 Rennes Cedex, France
| | | | | | | | - Cristelle Meriadec
- CNRS, UMR 6251, Institut de Physique de Rennes, 263 av. Général Leclerc, Université Rennes I, 35042 Rennes Cedex, France
| | - Camille Delvaux
- 1] CEA, Institute of Biology and Technologies of Saclay, 91191 CEA-Saclay, France [2] Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Sud, 91191 CEA-Saclay, Gif sur Yvette, France
| | - Thomas Bizien
- CNRS, UMR 6251, Institut de Physique de Rennes, 263 av. Général Leclerc, Université Rennes I, 35042 Rennes Cedex, France
| | - Emmanouil Kasotakis
- 1] CEA, Institute of Biology and Technologies of Saclay, 91191 CEA-Saclay, France [2] Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Sud, 91191 CEA-Saclay, Gif sur Yvette, France
| | - Carmen Lopez-Iglesias
- Cryo-Electron Microscopy Unit. Scientific and Tecnological Centers of the University of Barcelona, E-08028 Barcelona, Spain
| | - Andrew Gall
- 1] CEA, Institute of Biology and Technologies of Saclay, 91191 CEA-Saclay, France [2] Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Sud, 91191 CEA-Saclay, Gif sur Yvette, France
| | - Stéphane Bressanelli
- 1] CEA, Institute of Biology and Technologies of Saclay, 91191 CEA-Saclay, France [2] Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Sud, 91191 CEA-Saclay, Gif sur Yvette, France
| | - Marie-Hélène Le Du
- 1] CEA, Institute of Biology and Technologies of Saclay, 91191 CEA-Saclay, France [2] Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Sud, 91191 CEA-Saclay, Gif sur Yvette, France
| | - Maïté Paternostre
- 1] CEA, Institute of Biology and Technologies of Saclay, 91191 CEA-Saclay, France [2] Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Sud, 91191 CEA-Saclay, Gif sur Yvette, France
| | - Franck Artzner
- CNRS, UMR 6251, Institut de Physique de Rennes, 263 av. Général Leclerc, Université Rennes I, 35042 Rennes Cedex, France
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Butkus V, Gelzinis A, Augulis R, Gall A, Büchel C, Robert B, Zigmantas D, Valkunas L, Abramavicius D. Coherence and population dynamics of chlorophyll excitations in FCP complex: Two-dimensional spectroscopy study. J Chem Phys 2015; 142:212414. [DOI: 10.1063/1.4914098] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Affiliation(s)
- Vytautas Butkus
- Department of Theoretical Physics, Faculty of Physics, Vilnius University, Sauletekio Ave. 9-III, 10222 Vilnius, Lithuania
- Center for Physical Sciences and Technology, Savanoriu Ave. 231, 02300 Vilnius, Lithuania
| | - Andrius Gelzinis
- Department of Theoretical Physics, Faculty of Physics, Vilnius University, Sauletekio Ave. 9-III, 10222 Vilnius, Lithuania
- Center for Physical Sciences and Technology, Savanoriu Ave. 231, 02300 Vilnius, Lithuania
| | - Ramūnas Augulis
- Center for Physical Sciences and Technology, Savanoriu Ave. 231, 02300 Vilnius, Lithuania
| | - Andrew Gall
- Institut de Biologie et Technologies de Saclay, Bât 532, Commissariat à l’Energie Atomique Saclay, 91191 Gif sur Yvette, France
| | - Claudia Büchel
- Institut für Molekulare Biowissenschaften, Universität Frankfurt, Max-von-Laue-Straße 9, Frankfurt, Germany
| | - Bruno Robert
- Institut de Biologie et Technologies de Saclay, Bât 532, Commissariat à l’Energie Atomique Saclay, 91191 Gif sur Yvette, France
| | - Donatas Zigmantas
- Department of Chemical Physics, Lund University, P.O. Box 124, 22100 Lund, Sweden
| | - Leonas Valkunas
- Department of Theoretical Physics, Faculty of Physics, Vilnius University, Sauletekio Ave. 9-III, 10222 Vilnius, Lithuania
- Center for Physical Sciences and Technology, Savanoriu Ave. 231, 02300 Vilnius, Lithuania
| | - Darius Abramavicius
- Department of Theoretical Physics, Faculty of Physics, Vilnius University, Sauletekio Ave. 9-III, 10222 Vilnius, Lithuania
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Gelzinis A, Butkus V, Songaila E, Augulis R, Gall A, Büchel C, Robert B, Abramavicius D, Zigmantas D, Valkunas L. Mapping energy transfer channels in fucoxanthin–chlorophyll protein complex. Biochimica et Biophysica Acta (BBA) - Bioenergetics 2015; 1847:241-247. [DOI: 10.1016/j.bbabio.2014.11.004] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/22/2014] [Revised: 11/11/2014] [Accepted: 11/14/2014] [Indexed: 11/15/2022]
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Gall A, Pascal AA, Robert B. Vibrational techniques applied to photosynthesis: Resonance Raman and fluorescence line-narrowing. Biochim Biophys Acta 2014; 1847:12-8. [PMID: 25268562 DOI: 10.1016/j.bbabio.2014.09.009] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/23/2014] [Revised: 09/12/2014] [Accepted: 09/22/2014] [Indexed: 11/25/2022]
Abstract
Resonance Raman spectroscopy may yield precise information on the conformation of, and the interactions assumed by, the chromophores involved in the first steps of the photosynthetic process. Selectivity is achieved via resonance with the absorption transition of the chromophore of interest. Fluorescence line-narrowing spectroscopy is a complementary technique, in that it provides the same level of information (structure, conformation, interactions), but in this case for the emitting pigment(s) only (whether isolated or in an ensemble of interacting chromophores). The selectivity provided by these vibrational techniques allows for the analysis of pigment molecules not only when they are isolated in solvents, but also when embedded in soluble or membrane proteins and even, as shown recently, in vivo. They can be used, for instance, to relate the electronic properties of these pigment molecules to their structure and/or the physical properties of their environment. These techniques are even able to follow subtle changes in chromophore conformation associated with regulatory processes. After a short introduction to the physical principles that govern resonance Raman and fluorescence line-narrowing spectroscopies, the information content of the vibrational spectra of chlorophyll and carotenoid molecules is described in this article, together with the experiments which helped in determining which structural parameter(s) each vibrational band is sensitive to. A selection of applications is then presented, in order to illustrate how these techniques have been used in the field of photosynthesis, and what type of information has been obtained. This article is part of a Special Issue entitled: Vibrational spectroscopies and bioenergetic systems.
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Affiliation(s)
- Andrew Gall
- Institute of Biology and Technology Saclay, CEA, UMR 8221 CNRS, 91191 Gif/Yvette, France
| | - Andrew A Pascal
- Institute of Biology and Technology Saclay, CEA, UMR 8221 CNRS, 91191 Gif/Yvette, France
| | - Bruno Robert
- Institute of Biology and Technology Saclay, CEA, UMR 8221 CNRS, 91191 Gif/Yvette, France.
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Marx-Stoelting P, Niemann L, Ritz V, Ulbrich B, Gall A, Hirsch-Ernst KI, Pfeil R, Solecki R. Assessment of three approaches for regulatory decision making on pesticides with endocrine disrupting properties. Regul Toxicol Pharmacol 2014; 70:590-604. [PMID: 25239592 DOI: 10.1016/j.yrtph.2014.09.001] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [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: 04/07/2014] [Revised: 08/29/2014] [Accepted: 09/03/2014] [Indexed: 12/30/2022]
Abstract
Recent EU legislation has introduced endocrine disrupting properties as a hazard-based "cut-off" criterion for the approval of active substances as pesticides and biocides. Currently, no specific science-based approach for the assessment of substances with endocrine disrupting properties has been agreed upon, although this new legislation provides interim criteria based on classification and labelling. Different proposals for decision making on potential endocrine disrupting properties in human health risk assessment have been developed by the German Federal Institute for Risk Assessment (BfR) and other regulatory bodies. All these frameworks, although differing with regard to hazard characterisation, include a toxicological assessment of adversity of the effects, the evaluation of underlying modes/mechanisms of action in animals and considerations concerning the relevance of effects to humans. Three options for regulatory decision making were tested upon 39 pesticides for their applicability and to analyze their potential impact on the regulatory status of active substances that are currently approved for use in Europe: Option 1, based purely on hazard identification (adversity, mode of action, and the plausibility that both are related); Option 2, based on hazard identification and additional elements of hazard characterisation (severity and potency); Option 3, based on the interim criteria laid down in the recent EU pesticides legislation. Additionally, the data analysed in this study were used to address the questions, which parts of the endocrine system were affected, which studies were the most sensitive and whether no observed adverse effect levels were observed for substance with ED properties. The results of this exercise represent preliminary categorisations and must not be used as a basis for definitive regulatory decisions. They demonstrate that a combination of criteria for hazard identification with additional criteria of hazard characterisation allows prioritising and differentiating between substances with regard to their regulatory concern. It is proposed to integrate these elements into a decision matrix to be used within a weight of evidence approach for the toxicological categorisation of relevant endocrine disruptors and to consider all parts of the endocrine system for regulatory decision making on endocrine disruption.
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Affiliation(s)
- P Marx-Stoelting
- Bundesinstitut für Risikobewertung (Federal Institute for Risk Assessment), Max-Dohrn-Str 8-10, 10589 Berlin, Germany.
| | - L Niemann
- Bundesinstitut für Risikobewertung (Federal Institute for Risk Assessment), Max-Dohrn-Str 8-10, 10589 Berlin, Germany
| | - V Ritz
- Bundesinstitut für Risikobewertung (Federal Institute for Risk Assessment), Max-Dohrn-Str 8-10, 10589 Berlin, Germany
| | - B Ulbrich
- Bundesinstitut für Risikobewertung (Federal Institute for Risk Assessment), Max-Dohrn-Str 8-10, 10589 Berlin, Germany
| | - A Gall
- Bundesinstitut für Risikobewertung (Federal Institute for Risk Assessment), Max-Dohrn-Str 8-10, 10589 Berlin, Germany
| | - K I Hirsch-Ernst
- Bundesinstitut für Risikobewertung (Federal Institute for Risk Assessment), Max-Dohrn-Str 8-10, 10589 Berlin, Germany
| | - R Pfeil
- Bundesinstitut für Risikobewertung (Federal Institute for Risk Assessment), Max-Dohrn-Str 8-10, 10589 Berlin, Germany
| | - R Solecki
- Bundesinstitut für Risikobewertung (Federal Institute for Risk Assessment), Max-Dohrn-Str 8-10, 10589 Berlin, Germany
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Uragami C, Galzerano D, Gall A, Shigematsu Y, Meisterhans M, Oka N, Iha M, Fujii R, Robert B, Hashimoto H. Light-dependent conformational change of neoxanthin in a siphonous green alga, Codium intricatum, revealed by Raman spectroscopy. Photosynth Res 2014; 121:69-77. [PMID: 24861896 DOI: 10.1007/s11120-014-0011-y] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2013] [Accepted: 05/02/2014] [Indexed: 06/03/2023]
Abstract
Siphonous green algae, a type of deep-sea green algae, appear olive drab and utilize blue-green light for photosynthesis. A siphonous green alga, Codium (C.) intricatum, was isolated from Okinawa prefecture in Japan, and a clonal algal culture in filamentous form was established. The major light-harvesting antenna was analogous to the trimeric LHCII found in higher plants, but the C. intricatum complex contained an unusual carbonyl carotenoid siphonaxanthin. Culture conditions were optimized to achieve high siphonaxanthin content in intact lyophilized filamentous bodies. Interestingly, the carotenoid composition was different when cultured under high irradiance: all-trans neoxanthin was accumulated in addition to the normal 9'-cis form in whole cell extract. Resonance Raman spectra of intact filamentous bodies, cultured under high- and low-light conditions, confirmed the accumulation of all-trans neoxanthin under high irradiance conditions. A plausible function of the presence of all-trans neoxanthin will be discussed in relation to the regulation against high light stress.
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Affiliation(s)
- Chiasa Uragami
- Graduate School of Science, Osaka City University, 3-3-138 Sugimoto, Sumiyoshi-ku, Osaka, 558-8585, Japan
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Chmeliov J, Songaila E, Rancova O, Gall A, Robert B, Abramavicius D, Valkunas L. Excitons in the LH3 complexes from purple bacteria. J Phys Chem B 2013; 117:11058-68. [PMID: 23570515 DOI: 10.1021/jp400239z] [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: 02/05/2023]
Abstract
The noncovalently bound and structurally identical bacteriochlorophyll a chromophores in the peripheral light-harvesting complexes LH2 (B800-850) and LH3 (B800-820) from photosynthetic purple bacteria ensure the variability of the exciton spectra in the near-infrared (820-850 nm) wavelength region. As a result, the spectroscopic properties of the antenna complexes, such as positions of the maxima in the exciton absorption spectra, give rise to very efficient excitation transfer toward the reaction center. In this work, we investigated the possible molecular origin of the excitonically coupled B820 bacteriochlorophylls in LH3 using femtosecond transient absorption spectroscopy, deconvolution of steady-state absorption spectra, and modeling of the electrostatic intermolecular interactions using a charge density coupling approach. Compared to LH2, the upper excitonic level is red-shifted from 755 to 790 nm and is associated with an approximate 2-fold decrease of B820 intrapigment coupling. The absorption properties of LH3 cannot be reproduced by only changing the B850 site energy but also require a different scaling factor to be used to calculate interpigment couplings and a change of histidine protonation state. Several protonation patterns for distinct amino acid groups are presented, giving values of 162-173 cm(-1) at 100 K for the intradimer resonance interaction in the B820 ring.
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Affiliation(s)
- Jevgenij Chmeliov
- Institute of Physics, Center for Physical Sciences and Technology , Gostauto 11, LT-01108 Vilnius, Lithuania
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Mendes-Pinto MM, Sansiaume E, Hashimoto H, Pascal AA, Gall A, Robert B. Electronic Absorption and Ground State Structure of Carotenoid Molecules. J Phys Chem B 2013; 117:11015-21. [DOI: 10.1021/jp309908r] [Citation(s) in RCA: 84] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- Maria M. Mendes-Pinto
- Institute of Biology and Technology
Saclay, CEA, UMR 8221 CNRS, University Paris Sud, CEA Saclay 91191 Gif sur Yvette, France
| | - Elodie Sansiaume
- Institute of Biology and Technology
Saclay, CEA, UMR 8221 CNRS, University Paris Sud, CEA Saclay 91191 Gif sur Yvette, France
| | - Hideki Hashimoto
- The OCU Advanced Research Institute
for Natural Science and Technology (OCARINA) and CREST/JST, Osaka City University, 3-3-138 Sugimoto, Sumiyoshi-ku,
Osaka 558-8585, Japan
| | - Andrew A. Pascal
- Institute of Biology and Technology
Saclay, CEA, UMR 8221 CNRS, University Paris Sud, CEA Saclay 91191 Gif sur Yvette, France
| | - Andrew Gall
- Institute of Biology and Technology
Saclay, CEA, UMR 8221 CNRS, University Paris Sud, CEA Saclay 91191 Gif sur Yvette, France
| | - Bruno Robert
- Institute of Biology and Technology
Saclay, CEA, UMR 8221 CNRS, University Paris Sud, CEA Saclay 91191 Gif sur Yvette, France
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Trinkunas G, Zerlauskiene O, Urbonienė V, Chmeliov J, Gall A, Robert B, Valkunas L. Exciton Band Structure in Bacterial Peripheral Light-Harvesting Complexes. J Phys Chem B 2012; 116:5192-8. [DOI: 10.1021/jp302042w] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Gediminas Trinkunas
- Institute of Physics, Center for Physical Sciences and Technology, Savanoriu
Avenue 231, LT-02300 Vilnius, Lithuania
- Department of Theoretical Physics,
Faculty of Physics, Vilnius University,
Sauletekio Avenue 9, LT-10222 Vilnius, Lithuania
| | - Oksana Zerlauskiene
- Institute of Physics, Center for Physical Sciences and Technology, Savanoriu
Avenue 231, LT-02300 Vilnius, Lithuania
| | - Vidita Urbonienė
- Department of General Physics
and Spectroscopy, Faculty of Physics, Vilnius University, Sauletekio Avenue 9, LT-10222 Vilnius, Lithuania
| | - Jevgenij Chmeliov
- Institute of Physics, Center for Physical Sciences and Technology, Savanoriu
Avenue 231, LT-02300 Vilnius, Lithuania
- Department of Theoretical Physics,
Faculty of Physics, Vilnius University,
Sauletekio Avenue 9, LT-10222 Vilnius, Lithuania
| | - Andrew Gall
- Institute of Biology and Technology of Saclay, CNRS-URA2096, CEA-Saclay,
91911 Gif sur Yvette, France
| | - Bruno Robert
- Institute of Biology and Technology of Saclay, CNRS-URA2096, CEA-Saclay,
91911 Gif sur Yvette, France
| | - Leonas Valkunas
- Institute of Physics, Center for Physical Sciences and Technology, Savanoriu
Avenue 231, LT-02300 Vilnius, Lithuania
- Department of Theoretical Physics,
Faculty of Physics, Vilnius University,
Sauletekio Avenue 9, LT-10222 Vilnius, Lithuania
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Uragami C, Yamashita E, Gall A, Robert B, Hashimoto H. Application of resonance raman microscopy to in vivo carotenoid. Acta Biochim Pol 2012; 59:53-56. [PMID: 22428125] [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] [Received: 10/14/2011] [Accepted: 03/01/2012] [Indexed: 05/31/2023]
Abstract
The high antioxidant activity of astaxanthin has been attracted considerable attention in these days. One of the major antioxidant activities of this carotenoid is anti-photoaging. We have been focusing our attention on this particular issue. The anti-photoaging activity should be functioning in inner skin. In this study we tried to find out the fact that astaxanthin that has been swabbed on the outer surface of the skin has really passed through and reached to the inner skin. For this purpose resonance Raman microscopy was applied to the rat skin sample on which astaxanthin was swabbed on its outer surface. Astaxanthin gives rise to a unique Raman spectrum that is characteristic of its molecular structure. Therefore, we can easily identify the presence or absence of astaxanthin in the area of the rat skin that is subjected to this spectroscopic measurement. We used 532 nm laser light for probing the resonance Raman scattering of astaxanthin. Astaxanthin shows three strong Raman lines at 1508, 1145, and 993 cm(-1). These three lines are ascribable to the C=C stretching, C-C stretching, and C-CH(3) in-plane rocking vibrational modes, respectively. We have constructed confocal Raman microscope that has the spatial resolution of ca. 500 nm. Three-dimensional mapping of the Raman spectrum of astaxanthin has been performed in order to determine its distribution in the rat skin.
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Affiliation(s)
- Chiasa Uragami
- Department of Physics and CREST/JST, Graduate School of Science, Osaka City University, Sugimoto, Sumiyoshi-ku, Japan
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25
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Abstract
The high antioxidant activity of astaxanthin has been attracted considerable attention in these days. One of the major antioxidant activities of this carotenoid is anti-photoaging. We have been focusing our attention on this particular issue. The anti-photoaging activity should be functioning in inner skin. In this study we tried to find out the fact that astaxanthin that has been swabbed on the outer surface of the skin has really passed through and reached to the inner skin. For this purpose resonance Raman microscopy was applied to the rat skin sample on which astaxanthin was swabbed on its outer surface. Astaxanthin gives rise to a unique Raman spectrum that is characteristic of its molecular structure. Therefore, we can easily identify the presence or absence of astaxanthin in the area of the rat skin that is subjected to this spectroscopic measurement. We used 532 nm laser light for probing the resonance Raman scattering of astaxanthin. Astaxanthin shows three strong Raman lines at 1508, 1145, and 993 cm(-1). These three lines are ascribable to the C=C stretching, C-C stretching, and C-CH(3) in-plane rocking vibrational modes, respectively. We have constructed confocal Raman microscope that has the spatial resolution of ca. 500 nm. Three-dimensional mapping of the Raman spectrum of astaxanthin has been performed in order to determine its distribution in the rat skin.
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Gall A, Berera R, Alexandre MTA, Pascal AA, Bordes L, Mendes-Pinto MM, Andrianambinintsoa S, Stoitchkova KV, Marin A, Valkunas L, Horton P, Kennis JTM, van Grondelle R, Ruban A, Robert B. Molecular adaptation of photoprotection: triplet states in light-harvesting proteins. Biophys J 2011; 101:934-42. [PMID: 21843485 DOI: 10.1016/j.bpj.2011.05.057] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2011] [Revised: 05/12/2011] [Accepted: 05/13/2011] [Indexed: 10/17/2022] Open
Abstract
The photosynthetic light-harvesting systems of purple bacteria and plants both utilize specific carotenoids as quenchers of the harmful (bacterio)chlorophyll triplet states via triplet-triplet energy transfer. Here, we explore how the binding of carotenoids to the different types of light-harvesting proteins found in plants and purple bacteria provides adaptation in this vital photoprotective function. We show that the creation of the carotenoid triplet states in the light-harvesting complexes may occur without detectable conformational changes, in contrast to that found for carotenoids in solution. However, in plant light-harvesting complexes, the triplet wavefunction is shared between the carotenoids and their adjacent chlorophylls. This is not observed for the antenna proteins of purple bacteria, where the triplet is virtually fully located on the carotenoid molecule. These results explain the faster triplet-triplet transfer times in plant light-harvesting complexes. We show that this molecular mechanism, which spreads the location of the triplet wavefunction through the pigments of plant light-harvesting complexes, results in the absence of any detectable chlorophyll triplet in these complexes upon excitation, and we propose that it emerged as a photoprotective adaptation during the evolution of oxygenic photosynthesis.
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Affiliation(s)
- Andrew Gall
- CEA, Institute of Biology and Technology of Saclay, Gif sur Yvette, France
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McCarthy ID, Bloomer Z, Gall A, Keen R, Ferguson-Pell M. Changes in the structural and material properties of the tibia in patients with spinal cord injury. Spinal Cord 2011; 50:333-7. [PMID: 22124349 DOI: 10.1038/sc.2011.143] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
STUDY DESIGN A cross-sectional study. OBJECTIVES To measure the change of structural and material properties at different sites of the tibia in spinal cord-injured patients using peripheral quantitative computerised tomography (pQCT). SETTING Orthopaedic research centre (UK). METHODS Thirty-one subjects were measured--eight with acute spinal cord injury (SCI), nine with chronic SCI and fourteen able-bodied controls. pQCT scans were performed at 2% (proximal), 34% (diaphyseal) and 96% (distal) along the tibia from the tibial plateau. Structural measures of bone were calculated, and volumetric bone mineral density (vBMD) was also measured at all three levels. Muscle cross-sectional area was measured at the diaphyseal level. RESULTS Structurally, there were changes in the cortical bone; in the diaphysis, the shape of the cross-section changed to offer less resistance to AP bending, and the cross-sectional area of the cortical shell decreased both proximally and distally. There were corresponding changes in vBMD in the anterior aspect of the cortical diaphysis, as well as proximal and distal trabecular bone. Changes in muscle occurred more rapidly than changes in bone. CONCLUSION There were clear changes of both structure and material at all three levels of the tibia in chronic SCI patients. These changes were consistent with specific adaptations to reduced local mechanical loading conditions. To assess fracture risk in SCI and also to monitor the effect of therapeutic interventions, the structure of the bone should be considered in addition to trabecular bone mineral density.
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Affiliation(s)
- I D McCarthy
- UCL Institute of Orthopaedics and Musculoskeletal Science, Stanmore, UK.
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Kuppuswamy A, Balasubramaniam AV, Maksimovic R, Mathias CJ, Gall A, Craggs MD, Ellaway PH. Action of 5 Hz repetitive transcranial magnetic stimulation on sensory, motor and autonomic function in human spinal cord injury. Clin Neurophysiol 2011; 122:2452-61. [PMID: 21600843 DOI: 10.1016/j.clinph.2011.04.022] [Citation(s) in RCA: 49] [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: 11/02/2010] [Revised: 04/21/2011] [Accepted: 04/26/2011] [Indexed: 10/18/2022]
Abstract
OBJECTIVE To assess the effectiveness of physiological outcome measures in detecting functional change in the degree of impairment of spinal cord injury (SCI) following repetitive transcranial magnetic stimulation (rTMS) of the sensorimotor cortex. METHODS Subjects with complete or incomplete cervical (or T1) SCI received real and sham rTMS in a randomised placebo-controlled single-blinded cross-over trial. rTMS at sub-threshold intensity for upper-limb muscles was applied (5 Hz, 900 stimuli) on 5 consecutive days. Assessments made before and for 2 weeks after treatment comprised the ASIA (American Spinal Injuries Association) impairment scale (AIS), the Action Research Arm Test (ARAT), a peg-board test, electrical perceptual test (EPT), motor evoked potentials, cortical silent period, cardiovascular and sympathetic skin responses. RESULTS There were no significant differences in AIS outcomes between real and sham rTMS. The ARAT was increased at 1h after real rTMS compared to baseline. Active motor threshold for the most caudally innervated hand muscle was increased at 72 and 120 h compared to baseline. Persistent reductions in EPT to rTMS occurred in two individuals. CONCLUSIONS Changes in cortical motor threshold measures may accompany functional gains to rTMS in SCI subjects. SIGNIFICANCE Electrophysiological measures may provide a useful adjunct to ASIA impairment scales.
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Affiliation(s)
- A Kuppuswamy
- Division of Experimental Medicine, Imperial College London, London W6 8RP, UK
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Ellaway P, Kuppuswamy A, Balasubramaniam A, Maksimovic R, Gall A, Craggs M, Mathias C, Bacon M, Prochazka A, Kowalczewski J, Conway B, Galen S, Catton C, Allan D, Curt A, Wirth B, van Hedel H. Development of quantitative and sensitive assessments of physiological and functional outcome during recovery from spinal cord injury: A Clinical Initiative. Brain Res Bull 2011; 84:343-57. [DOI: 10.1016/j.brainresbull.2010.08.007] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2010] [Revised: 08/11/2010] [Accepted: 08/12/2010] [Indexed: 01/30/2023]
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Bubbear JS, Gall A, Middleton FRI, Ferguson-Pell M, Swaminathan R, Keen RW. Early treatment with zoledronic acid prevents bone loss at the hip following acute spinal cord injury. Osteoporos Int 2011; 22:271-9. [PMID: 20358358 DOI: 10.1007/s00198-010-1221-6] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/24/2009] [Accepted: 01/19/2010] [Indexed: 12/13/2022]
Abstract
UNLABELLED Osteoporosis after spinal cord injury is common. Reductions in bone density are rapid and fracture rates are higher after injury. Early treatment with 4 mg zoledronic acid significantly reduced bone loss at the hip compared to untreated individuals in the first year. Treatment appeared safe and well tolerated. INTRODUCTION Bone mineral density (BMD) is lost rapidly following spinal cord injury (SCI), predominantly in the lower limbs. Bone turnover markers suggest an early increase in resorption. METHODS A randomised, open-label study of 14 patients with acute SCI randomised to receive 4 mg IV zoledronic acid or standard treatment. BMD was measured by dual-X-ray absorptiometry at the lumbar spine and hip (femoral neck, total and trochanter) at baseline, 3, 6 and 12 months. Bone turnover markers (serum C-terminal telopeptide and Procollagen I N-terminal peptide and urinary N-terminal telopeptide/Cr ratio) were also measured. RESULTS After 12 months, there was a significant difference in BMD between the groups at the total hip (12.4%, p = 0.005), trochanter (13.4%, p = 0.028) and lumbar spine (2.7%, p = 0.033). However, the difference between groups at the femoral neck was not significant (4.8%, p = 0.741). In the treated group, bone resorption was reduced and remained reduced up to 12 months. Other than flu-like symptoms immediately after the infusion, no adverse events were observed. CONCLUSION IV zoledronic acid is an effective and well-tolerated treatment to prevent bone mineral density loss at the total hip and trochanter for up to 12 months following SCI.
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Affiliation(s)
- J S Bubbear
- Metabolic Unit, Royal National Orthopaedic Hospital, Brockley Hill, Stanmore, HA7 4LP, UK.
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31
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Korn A, Ajlani G, Lagoutte B, Gall A, Sétif P. Ferredoxin:NADP+ oxidoreductase association with phycocyanin modulates its properties. J Biol Chem 2009; 284:31789-97. [PMID: 19759024 DOI: 10.1074/jbc.m109.024638] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
In photosynthetic organisms, ferredoxin:NADP(+) oxidoreductase (FNR) is known to provide NADPH for CO(2) assimilation, but it also utilizes NADPH to provide reduced ferredoxin. The cyanobacterium Synechocystis sp. strain PCC6803 produces two FNR isoforms, a small one (FNR(S)) similar to the one found in plant plastids and a large one (FNR(L)) that is associated with the phycobilisome, a light-harvesting complex. Here we show that a mutant lacking FNR(L) exhibits a higher NADP(+)/NADPH ratio. We also purified to homogeneity a phycobilisome subcomplex comprising FNR(L,) named FNR(L)-PC. The enzymatic activities of FNR(L)-PC were compared with those of FNR(S). During NADPH oxidation, FNR(L)-PC exhibits a 30% decrease in the Michaelis constant K(m)((NADPH)), and a 70% increase in K(m)((ferredoxin)), which is in agreement with its predicted lower activity of ferredoxin reduction. During NADP(+) reduction, the FNR(L)-PC shows a 29/43% decrease in the rate of single electron transfer from reduced ferredoxin in the presence/absence of NADP(+). The increase in K(m)((ferredoxin)) and the rate decrease of single reduction are attributed to steric hindrance by the phycocyanin moiety of FNR(L)-PC. Both isoforms are capable of catalyzing the NADP(+) reduction under multiple turnover conditions. Furthermore, we obtained evidence that, under high ionic strength conditions, electron transfer from reduced ferredoxin is rate limiting during this process. The differences that we observe might not fully explain the in vivo properties of the Synechocystis mutants expressing only one of the isoforms. Therefore, we advocate that FNR localization and/or substrates availability are essential in vivo.
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Affiliation(s)
- Anja Korn
- Institut de Biologie et de Technologie de Saclay, Commissariat à L'Energie Atomique, CNRS, F-91191 Gif sur Yvette, France
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Zerlauskiene O, Trinkunas G, Gall A, Robert B, Urboniene V, Valkunas L. Static and Dynamic Protein Impact on Electronic Properties of Light-Harvesting Complex LH2. J Phys Chem B 2008; 112:15883-92. [DOI: 10.1021/jp803439w] [Citation(s) in RCA: 37] [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] [Indexed: 11/28/2022]
Affiliation(s)
- O. Zerlauskiene
- Institute of Physics, Savanoriu 231, LT-02300 Vilnius, Lithuania, CEA, Institut de Biologie et Technologies de Saclay, and CNRS, 91191 Gif sur Yvette Cedex, France, Department of General Physics and Spectroscopy, Vilnius University, Sauletekio 9, LT-10222 Vilnius, Lithuania, and Department of Theoretical Physics, Vilnius University, Sauletekio 9, LT-10222 Vilnius, Lithuania
| | - G. Trinkunas
- Institute of Physics, Savanoriu 231, LT-02300 Vilnius, Lithuania, CEA, Institut de Biologie et Technologies de Saclay, and CNRS, 91191 Gif sur Yvette Cedex, France, Department of General Physics and Spectroscopy, Vilnius University, Sauletekio 9, LT-10222 Vilnius, Lithuania, and Department of Theoretical Physics, Vilnius University, Sauletekio 9, LT-10222 Vilnius, Lithuania
| | - A. Gall
- Institute of Physics, Savanoriu 231, LT-02300 Vilnius, Lithuania, CEA, Institut de Biologie et Technologies de Saclay, and CNRS, 91191 Gif sur Yvette Cedex, France, Department of General Physics and Spectroscopy, Vilnius University, Sauletekio 9, LT-10222 Vilnius, Lithuania, and Department of Theoretical Physics, Vilnius University, Sauletekio 9, LT-10222 Vilnius, Lithuania
| | - B. Robert
- Institute of Physics, Savanoriu 231, LT-02300 Vilnius, Lithuania, CEA, Institut de Biologie et Technologies de Saclay, and CNRS, 91191 Gif sur Yvette Cedex, France, Department of General Physics and Spectroscopy, Vilnius University, Sauletekio 9, LT-10222 Vilnius, Lithuania, and Department of Theoretical Physics, Vilnius University, Sauletekio 9, LT-10222 Vilnius, Lithuania
| | - V. Urboniene
- Institute of Physics, Savanoriu 231, LT-02300 Vilnius, Lithuania, CEA, Institut de Biologie et Technologies de Saclay, and CNRS, 91191 Gif sur Yvette Cedex, France, Department of General Physics and Spectroscopy, Vilnius University, Sauletekio 9, LT-10222 Vilnius, Lithuania, and Department of Theoretical Physics, Vilnius University, Sauletekio 9, LT-10222 Vilnius, Lithuania
| | - L. Valkunas
- Institute of Physics, Savanoriu 231, LT-02300 Vilnius, Lithuania, CEA, Institut de Biologie et Technologies de Saclay, and CNRS, 91191 Gif sur Yvette Cedex, France, Department of General Physics and Spectroscopy, Vilnius University, Sauletekio 9, LT-10222 Vilnius, Lithuania, and Department of Theoretical Physics, Vilnius University, Sauletekio 9, LT-10222 Vilnius, Lithuania
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Herbert RA, Gall A, Maoka T, Cogdell RJ, Robert B, Takaichi S, Schwabe S. Phototrophic purple sulfur bacteria as heat engines in the South Andros Black Hole. Photosynth Res 2008; 95:261-8. [PMID: 17906940 DOI: 10.1007/s11120-007-9246-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2007] [Accepted: 09/07/2007] [Indexed: 05/17/2023]
Abstract
Photosynthetic organisms normally endeavor to optimize the efficiency of their light-harvesting apparatus. However, here we describe two bacterial isolates belonging to the genera Allochromatium and Thiocapsa that demonstrate a novel adaptation by optimizing their external growth conditions at the expense of photosynthetic efficiency. In the South Andros Black Hole, Bahamas, a dense l-m thick layer of these anoxygenic purple sulfur bacteria is present at a depth of 17.8 m. In this layer the water temperature increases sharply to 36 degrees C as a consequence of the low-energy transfer efficiency of their carotenoids (ca. 30%). These include spirilloxanthin, and related polyene molecules and a novel chiral carotenoid identified as spirilloxanthin-2-ol, not previously reported in purple bacteria. To our knowledge, this study presents the first evidence of such a bacterial mass significantly increasing the ambient water temperature. The transduction of light to heat energy to excess heat may provide these anoxygenic phototropic bacteria with a competitive advantage over non-thermotolerant species, which would account for their predominance within the microbial layer.
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Affiliation(s)
- Rodney A Herbert
- Division of Environmental and Applied Biology, School of Life Sciences, University of Dundee, Dundee, DD1 4HN, UK.
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Abstract
Rabbit haemorrhagic disease (RHD) is usually a fatal disease in rabbits which has spread rapidly across the continents. While previous studies suggested persistence in rabbits to be an important factor in the epidemiology, the relevance of field virus infection of immune rabbits has not been investigated in experimentally infected animals before. This report describes for the first time the persistence of rabbit haemorrhagic disease virus (RHDV) genome for at least 15 weeks in rabbits immunized with an inactivated vaccine as well as a subunit vaccine and subsequently challenged with virulent RHDV. The viral RNA loads were determined by real-time reverse transcription-polymerase chain reaction. No conspicuous association of the detectable amount of RHDV RNA with the type of vaccine, the time after infection and--with one exception--the level of RHDV-specific antibodies in the immunized animals was observed. The results presented in this study are an urgent evidence for the existence of carrier animals as an important factor in the epidemiology of RHD.
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Affiliation(s)
- A Gall
- Friedrich-Loeffler-Institut, Institute of Diagnostic Virology, Boddenblick 5a, 17493 Greifswald-Insel Riems, Germany
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Urboniene V, Vrublevskaja O, Trinkunas G, Gall A, Robert B, Valkunas L. Solvation effect of bacteriochlorophyll excitons in light-harvesting complex LH2. Biophys J 2007; 93:2188-98. [PMID: 17513366 PMCID: PMC1959563 DOI: 10.1529/biophysj.106.103093] [Citation(s) in RCA: 27] [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] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
We have characterized the influence of the protein environment on the spectral properties of the bacteriochlorophyll (Bchl) molecules of the peripheral light-harvesting (or LH2) complex from Rhodobacter sphaeroides. The spectral density functions of the pigments responsible for the 800 and 850 nm electronic transitions were determined from the temperature dependence of the Bchl absorption spectra in different environments (detergent micelles and native membranes). The spectral density function is virtually independent of the hydrophobic support that the protein experiences. The reorganization energy for the B850 Bchls is 220 cm(-1), which is almost twice that of the B800 Bchls, and its Huang-Rhys factor reaches 8.4. Around the transition point temperature, and at higher temperatures, both the static spectral inhomogeneity and the resonance interactions become temperature-dependent. The inhomogeneous distribution function of the transitions exhibits less temperature dependence when LH2 is embedded in membranes, suggesting that the lipid phase protects the protein. However, the temperature dependence of the fluorescence spectra of LH2 cannot be fitted using the same parameters determined from the analysis of the absorption spectra. Correct fitting requires the lowest exciton states to be additionally shifted to the red, suggesting the reorganization of the exciton spectrum.
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Affiliation(s)
- V Urboniene
- Department of General Physics and Spectroscopy, Vilnius University, Vilnius, Lithuania
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Gall A, Hoffmann B, Teifke JP, Lange B, Schirrmeier H. Persistence of viral RNA in rabbits which overcome an experimental RHDV infection detected by a highly sensitive multiplex real-time RT-PCR. Vet Microbiol 2007; 120:17-32. [PMID: 17112688 DOI: 10.1016/j.vetmic.2006.10.006] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2005] [Revised: 07/18/2006] [Accepted: 10/04/2006] [Indexed: 11/18/2022]
Abstract
An internally controlled multiplex real-time RT-PCR using TaqMan probes and external standards for absolute RNA quantification was developed as a new diagnostic tool for the detection of rabbit haemorrhagic disease virus (RHDV). The test revealed a specificity of 100%, an analytical sensitivity of 10 copies/well and a linearity over a range from 10(1) to 10(10) copies. The viral loads in organs, leukocytes, sera and excretions of seropositive, convalescent rabbits which were overcoming an experimental infection with RHDV were determined using the validated assay. As a result, viral RNA was demonstrated and quantified for at least 15 weeks. Thus, a persistence of viral RNA after experimental infection of rabbits could be shown for the first time. In contrast, neither antigen nor infectious virus could be detected by antigen-ELISA, immunohistochemistry or experimental transmission. Therefore, further experiments are necessary to prove that the persistence of RNA is linked with the persistence of infectious virus particles.
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Affiliation(s)
- A Gall
- Friedrich-Loeffler-Institut, Institute of Diagnostic Virology, Boddenblick 5a, 17493 Greifswald-Insel Riems, Germany
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Cogdell RJ, Gall A, Köhler J. The architecture and function of the light-harvesting apparatus of purple bacteria: from single molecules to in vivo membranes. Q Rev Biophys 2006; 39:227-324. [PMID: 17038210 DOI: 10.1017/s0033583506004434] [Citation(s) in RCA: 468] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
This review describes the structures of the two major integral membrane pigment complexes, the RC-LH1 'core' and LH2 complexes, which together make up the light-harvesting system present in typical purple photosynthetic bacteria. The antenna complexes serve to absorb incident solar radiation and to transfer it to the reaction centres, where it is used to 'power' the photosynthetic redox reaction and ultimately leads to the synthesis of ATP. Our current understanding of the biosynthesis and assembly of the LH and RC complexes is described, with special emphasis on the roles of the newly described bacteriophytochromes. Using both the structural information and that obtained from a wide variety of biophysical techniques, the details of each of the different energy-transfer reactions that occur, between the absorption of a photon and the charge separation in the RC, are described. Special emphasis is given to show how the use of single-molecule spectroscopy has provided a more detailed understanding of the molecular mechanisms involved in the energy-transfer processes. We have tried, with the help of an Appendix, to make the details of the quantum mechanics that are required to appreciate these molecular mechanisms, accessible to mathematically illiterate biologists. The elegance of the purple bacterial light-harvesting system lies in the way in which it has cleverly exploited quantum mechanics.
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Affiliation(s)
- Richard J Cogdell
- Biomedical Research Building, Institute of Biomedical and Life Sciences, University of Glasgow, Glasgow, UK.
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Gall A, Gardiner AT, Cogdell RJ, Robert B. Carotenoid stoichiometry in the LH2 crystal: No spectral evidence for the presence of the second molecule in the α/β-apoprotein dimer. FEBS Lett 2006; 580:3841-4. [PMID: 16790242 DOI: 10.1016/j.febslet.2006.06.005] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2006] [Revised: 05/30/2006] [Accepted: 06/02/2006] [Indexed: 11/18/2022]
Abstract
In this work we have investigated the carotenoid-protein interactions in LH2 complexes of Rhodopseudomonas acidophila both in "free in solution" mixed-micelles and in three-dimensional crystals by Raman spectroscopy in resonance with the carotenoid (Car) molecules. We show that the Car molecules when bound to their binding pockets show no significant differences when the complexes are "free in solution" or packed in crystalline arrays. Furthermore, there is no significant wavelength dependence in the Raman spectrum of the Car molecules of LH2. This indicates that there is only one Car configuration in LH2 and thus only one molecule per alpha/beta-heterodimer.
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Affiliation(s)
- Andrew Gall
- Service de Biophysique des Fonctions Membranaires, Département de Biologie Joliot Curie/CEA et URA CNRS 2096, CEA Saclay, 91191 Gif-sur-Yvette Cedex, France.
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Rutkauskas D, Novoderezhkin V, Gall A, Olsen J, Cogdell RJ, Hunter CN, van Grondelle R. Spectral trends in the fluorescence of single bacterial light-harvesting complexes: experiments and modified redfield simulations. Biophys J 2006; 90:2475-85. [PMID: 16399834 PMCID: PMC1403191 DOI: 10.1529/biophysj.105.075903] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.7] [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: 11/18/2022] Open
Abstract
In this work we present and discuss the single-molecule fluorescence spectra of a variety of species of light-harvesting complexes: LH2 of Rhodopseudomonas acidophila, Rhodobacter sphaeroides, and Rhodospirillum molischianum and LH1 of Rhodobacter sphaeroides. The emission spectrum of these complexes varies as a function of time as was described in earlier work. For each type of complex, we observe a pronounced and well-reproducible characteristic relationship between the fluorescence spectral parameters of the peak wavelength, width, and asymmetry. This dependence for the LH2 complexes can be quantitatively explained on the basis of a disordered exciton model by varying the static disorder and phonon coupling parameters. In addition, a correlation of the pigment site energies has to be assumed to interpret the behavior of the LH1 complex.
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Affiliation(s)
- Danielis Rutkauskas
- Department of Biophysics and Physics of Complex Systems, Division of Physics and Astronomy, Faculty of Sciences, Vrije Universiteit, 1081 HV Amsterdam, The Netherlands.
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Rutkauskas D, Olsen J, Gall A, Cogdell RJ, Hunter CN, van Grondelle R. Comparative study of spectral flexibilities of bacterial light-harvesting complexes: structural implications. Biophys J 2006; 90:2463-74. [PMID: 16399835 PMCID: PMC1403163 DOI: 10.1529/biophysj.105.075895] [Citation(s) in RCA: 28] [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] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
This work presents a comparative study of the frequencies of spectral jumping of individual light-harvesting complexes of six different types: LH2 of Rhodopseudomonas acidophila, Rhodobacter sphaeroides, and Rhodospirillum molischianum; LH1 of Rhodobacter sphaeroides; and two "domain swap mutants" of LH2 of Rhodobacter sphaeroides: PACLH1 and PACLH2mol, in which the alpha-polypeptide C-terminus is exchanged with the corresponding sequence from LH1 of Rhodobacter sphaeroides or LH2 of Rhodospirillum molischianum, respectively. The quasistable states of fluorescence peak wavelength that were previously observed for the LH2 of Rps. acidophila were confirmed for other species. We also observed occurrences of extremely blue-shifted spectra, which were associated with reversible bleaching of one of the chromophore rings. Different jumping behavior is observed for single complexes of different types investigated with the same equivalent excitation intensity. The differences in spectral diffusion are associated with subtle differences of the binding pocket of B850 pigments and the structural flexibility of the different types of complexes.
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Affiliation(s)
- Danielis Rutkauskas
- Department of Biophysics and Physics of Complex Systems, Division of Physics and Astronomy, Faculty of Sciences, Vrije Universiteit, 1081 HV Amsterdam, The Netherlands.
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Gall A, Henry S, Takaichi S, Robert B, Cogdell RJ. Preferential incorporation of coloured-carotenoids occurs in the LH2 complexes from non-sulphur purple bacteria under carotenoid-limiting conditions. Photosynth Res 2005; 86:25-35. [PMID: 16172923 DOI: 10.1007/s11120-005-3481-0] [Citation(s) in RCA: 31] [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] [Subscribe] [Scholar Register] [Received: 11/30/2004] [Accepted: 03/09/2005] [Indexed: 05/04/2023]
Abstract
The effect of growing Rhodopseudomonas (Rps.) acidophila and Rps. palustris in the presence of different concentrations of the carotenoid (Car) biosynthetic inhibitor diphenylamine (DPA) has been investigated. Growth with sub-maximal concentrations of DPA induces Car limitation. The exact response to DPA is species dependent. However, both Rps. acidophila and Rps. palustris respond by preferentially incorporating the limiting amount of coloured Cars into their LH2 complexes at the expense of the RC-LH1 complexes. As inhibition by DPA becomes more severe there is an increase in the percentage of Cars with reduced numbers of conjugated C=C bonds. The effect of this changed Car composition on the structure and function of the antenna complexes has been investigated using absorption, fluorescence, CD and Raman spectroscopies. The results show that although the presence of Car molecules is important for the stability of the LH2 complexes that the overall native structure can be maintained by the presence of many different Cars.
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Affiliation(s)
- Andrew Gall
- Division of Biochemistry and Molecular Biology, Institute of Biomedical and Life Sciences, University of Glasgow, Glasgow, G12 8QQ, UK.
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Urboniene V, Vrublevskaja O, Gall A, Trinkunas G, Robert B, Valkunas L. Temperature broadening of LH2 absorption in glycerol solution. Photosynth Res 2005; 86:49-59. [PMID: 16172925 DOI: 10.1007/s11120-005-2748-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2004] [Accepted: 02/21/2005] [Indexed: 05/04/2023]
Abstract
In order to determine the relationship between the pigment-protein and the pigment-pigment interactions, the measurements of absorption spectra of the peripheral light-harvesting complex LH2 from the purple bacteria Rhodobacter sphaeroides solvated in glycerol/buffer solution were carried out in a wide temperature range, from 4 to 250 K. The SDFs used for simulating the temperature dependence of B800 and B850 bands were determined in a parametric form. To fit experimental spectra the overall exciton-phonon coupling had to be assumed to be weak for B850 (lambda/2V approximately 0.3, where lambda is the reorganization energy and V is the nearest-neighbor dipole-dipole coupling for bacteriochlorophylls). At physiological temperatures the intermediate nuclear bath dynamics compares with the magnitude of energy gap fluctuations. Slower dynamics with kappa approximately 0.39, where kappa is the ratio of the nuclear relaxation rate and the line width parameter, determines the spectral shape of B850 whilst faster modulations characterize B800 (kappa approximately 2.39). The static disorder for the B800 band is relatively high with the characteristic value of the inhomogeneous bandwidth Gamma(inh) approximately 120 cm-1, while for the B850 band this value is almost equal to the dipole-dipole coupling strength (Gamma(inh) approximately 360 cm-1). It has been found that the LH2 absorption spectrum is likely to be influenced by the temperature dependence of the dielectric constant of the solution in the high temperature range, when the glycerol/buffer solution is in the liquid state.
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Affiliation(s)
- V Urboniene
- Service de Biophysique des Protéines et des Membranes, DBJC/CEA and CNRS/URA2096, C.E.A. Saclay, 91191, Gif-sur-Yvette, Cedex, France.
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Gall A, Ellervee A, Robert B, Freiberg A. The effect of internal voids in membrane proteins: high-pressure study of two photochemical reaction centres from Rhodobacter sphaeroides. FEBS Lett 2004; 560:221-5. [PMID: 14988026 DOI: 10.1016/s0014-5793(04)00117-6] [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] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2003] [Revised: 12/31/2003] [Accepted: 01/23/2004] [Indexed: 11/15/2022]
Abstract
The effect of application of high pressure on the carotenoid-containing bacterial reaction centre from Rhodobacter sphaeroides strain 2.4.1 was studied, and compared to recent experiments performed on its carotenoid-less counterpart, isolated from strain R26.1. Our results indicate that the cavity created by the absence of carotenoid contributes to localised differences in protein compressibility when using the intrinsic chromophores as molecular probes. Differential stability of the electronic transitions of the primary electron donor under high hydrostatic pressure is observed, dependent on the presence of the carotenoid cofactor. This suggests that the transition intensity loss is induced by a slight change of the primary electron donor structure, allowed by the void created by the absence of the carotenoid molecule.
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Affiliation(s)
- Andrew Gall
- Service de Biophysique des Fonctions Membranaires, DBJC/CEA and URA CNRS 2096, CEA-Saclay, 91191 Gif-sur-Yvette Cedex, France.
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Gall A, Ellervee A, Sturgis JN, Fraser NJ, Cogdell RJ, Freiberg A, Robert B. Membrane protein stability: high pressure effects on the structure and chromophore-binding properties of the light-harvesting complex LH2. Biochemistry 2004; 42:13019-26. [PMID: 14596617 DOI: 10.1021/bi0350351] [Citation(s) in RCA: 32] [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] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Using the bacteriochlorophyll a (Bchl) cofactors as intrinsic probes to monitor changes in membrane protein structure, we investigate the response to high-pressure of the LH2 complexes from the photosynthetic bacteria Rhodobacter sphaeroides 2.4.1 and Rhodopseudomonas acidophila 10050. By FT-Raman spectroscopy, we demonstrate that high pressure does not induce significant distortion of the protein-bound 850 nm-absorbing bacteriochlorophyll molecules, or break of the hydrogen bond they are involved in. This indicates in particular that the oligomerization of the polypeptides is not perturbed up to 0.6 GPa. The pressure-induced changes in the Bchl absorption spectra are attributed to pigment-pigment interactions. In contrast, the loss of 800 nm-absorbing bacteriochlorophyll reflects pressure-induced alterations to the tertiary structure of the protein in proximity to the membrane/cytosol interface. This suggests that the LH2 protein does have two independent structural domains. The first domain is pressure independent and comprises mostly the C-terminal domain. The second domain located on the N-terminal side exhibits sensitivity to pressure and pH reminiscent of soluble proteins. The LH2 thus constitutes a suitable model system for studying in detail the stability of membrane-embedded hydrophobic helices and helices located at or close to the solvent/membrane interface.
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Affiliation(s)
- Andrew Gall
- Division of Biochemistry and Molecular Biology, IBLS, University of Glasgow, Glasgow G128QQ, Scotland.
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Gall A, Cogdell RJ, Robert B. Influence of carotenoid molecules on the structure of the bacteriochlorophyll binding site in peripheral light-harvesting proteins from Rhodobacter sphaeroides. Biochemistry 2003; 42:7252-8. [PMID: 12795622 DOI: 10.1021/bi0268293] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
In the LH2 proteins from Rhodobacter (Rb.) sphaeroides, the hydrogen bonds between the bacteriochlorophyll (Bchl) molecules and their proteic binding sites exhibit a strong variance with respect to carotenoid content and type. In the absence of the carotenoid molecule, such as in the LH2 from Rb. sphaeroides R26.1, the void in the protein structure induces a significant reorganization of the binding site of both Bchl molecules responsible for the 850 nm absorption, which is not observed when the 800 nm absorbing Bchl is selectively removed from these complexes. FT Raman spectra of LH2 complexes from Rb. sphaeroides show that the strength of the hydrogen bond between the 850 nm absorbing Bchl bound to the alpha polypeptide and the tyrosine alpha(45) depends precisely on the chemical nature of the bound carotenoid. These results suggest that the variable extremity of the carotenoid is embedded in these LH2 complexes, lying close to the interacting Bchl molecules. In the LH2 from Rhodopseudomonas acidophila, the equivalent part of the rhodopin glucoside, which bears the glucose group, lies close to the amino terminal of the antenna polypeptide. This contrast suggests that the structure of the carotenoid binding site in LH2 complexes strongly depends on the bacterial species and/or on the chemical nature of the bound carotenoid.
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Affiliation(s)
- Andrew Gall
- Division of Biochemistry and Molecular Biology-IBLS, University of Glasgow, Glasgow G12 8QQ, UK.
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Papagiannakis E, Das SK, Gall A, van Stokkum IHM, Robert B, van Grondelle R, Frank HA, Kennis JTM. Light Harvesting by Carotenoids Incorporated into the B850 Light-Harvesting Complex from Rhodobacter sphaeroides R-26.1: Excited-State Relaxation, Ultrafast Triplet Formation, and Energy Transfer to Bacteriochlorophyll. J Phys Chem B 2003. [DOI: 10.1021/jp027174i] [Citation(s) in RCA: 101] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Emmanouil Papagiannakis
- Department of Biophysics, Division of Physics and Astronomy, Vrije Universiteit, De Boelelaan 1081, 1081 HV, Amsterdam, The Netherlands, Department of Chemistry, 55 North Eagleville Road, University of Connecticut, Storrs, Connecticut 06269-3060, Division of Biochemistry and Molecular Biology, IBLS, University of Glasgow, Glasgow G128QQ, United Kingdom, and Service de Biophysique des fonctions Membranaires, DBJC/CEA et URA CNRS 2096, CEA Saclay, 91191 Gif/Yvette Cedex, France
| | - Somes Kumar Das
- Department of Biophysics, Division of Physics and Astronomy, Vrije Universiteit, De Boelelaan 1081, 1081 HV, Amsterdam, The Netherlands, Department of Chemistry, 55 North Eagleville Road, University of Connecticut, Storrs, Connecticut 06269-3060, Division of Biochemistry and Molecular Biology, IBLS, University of Glasgow, Glasgow G128QQ, United Kingdom, and Service de Biophysique des fonctions Membranaires, DBJC/CEA et URA CNRS 2096, CEA Saclay, 91191 Gif/Yvette Cedex, France
| | - Andrew Gall
- Department of Biophysics, Division of Physics and Astronomy, Vrije Universiteit, De Boelelaan 1081, 1081 HV, Amsterdam, The Netherlands, Department of Chemistry, 55 North Eagleville Road, University of Connecticut, Storrs, Connecticut 06269-3060, Division of Biochemistry and Molecular Biology, IBLS, University of Glasgow, Glasgow G128QQ, United Kingdom, and Service de Biophysique des fonctions Membranaires, DBJC/CEA et URA CNRS 2096, CEA Saclay, 91191 Gif/Yvette Cedex, France
| | - Ivo H. M. van Stokkum
- Department of Biophysics, Division of Physics and Astronomy, Vrije Universiteit, De Boelelaan 1081, 1081 HV, Amsterdam, The Netherlands, Department of Chemistry, 55 North Eagleville Road, University of Connecticut, Storrs, Connecticut 06269-3060, Division of Biochemistry and Molecular Biology, IBLS, University of Glasgow, Glasgow G128QQ, United Kingdom, and Service de Biophysique des fonctions Membranaires, DBJC/CEA et URA CNRS 2096, CEA Saclay, 91191 Gif/Yvette Cedex, France
| | - Bruno Robert
- Department of Biophysics, Division of Physics and Astronomy, Vrije Universiteit, De Boelelaan 1081, 1081 HV, Amsterdam, The Netherlands, Department of Chemistry, 55 North Eagleville Road, University of Connecticut, Storrs, Connecticut 06269-3060, Division of Biochemistry and Molecular Biology, IBLS, University of Glasgow, Glasgow G128QQ, United Kingdom, and Service de Biophysique des fonctions Membranaires, DBJC/CEA et URA CNRS 2096, CEA Saclay, 91191 Gif/Yvette Cedex, France
| | - Rienk van Grondelle
- Department of Biophysics, Division of Physics and Astronomy, Vrije Universiteit, De Boelelaan 1081, 1081 HV, Amsterdam, The Netherlands, Department of Chemistry, 55 North Eagleville Road, University of Connecticut, Storrs, Connecticut 06269-3060, Division of Biochemistry and Molecular Biology, IBLS, University of Glasgow, Glasgow G128QQ, United Kingdom, and Service de Biophysique des fonctions Membranaires, DBJC/CEA et URA CNRS 2096, CEA Saclay, 91191 Gif/Yvette Cedex, France
| | - Harry A. Frank
- Department of Biophysics, Division of Physics and Astronomy, Vrije Universiteit, De Boelelaan 1081, 1081 HV, Amsterdam, The Netherlands, Department of Chemistry, 55 North Eagleville Road, University of Connecticut, Storrs, Connecticut 06269-3060, Division of Biochemistry and Molecular Biology, IBLS, University of Glasgow, Glasgow G128QQ, United Kingdom, and Service de Biophysique des fonctions Membranaires, DBJC/CEA et URA CNRS 2096, CEA Saclay, 91191 Gif/Yvette Cedex, France
| | - John T. M. Kennis
- Department of Biophysics, Division of Physics and Astronomy, Vrije Universiteit, De Boelelaan 1081, 1081 HV, Amsterdam, The Netherlands, Department of Chemistry, 55 North Eagleville Road, University of Connecticut, Storrs, Connecticut 06269-3060, Division of Biochemistry and Molecular Biology, IBLS, University of Glasgow, Glasgow G128QQ, United Kingdom, and Service de Biophysique des fonctions Membranaires, DBJC/CEA et URA CNRS 2096, CEA Saclay, 91191 Gif/Yvette Cedex, France
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Gall A, Seguin J, Robert B, Bellissent-Funel MC. Membrane Proteins in Bulk Solution Can Be Used for Quasi-Elastic Neutron Scattering Studies: The Case for the Photochemical Reaction Center. J Phys Chem B 2002. [DOI: 10.1021/jp014079l] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Andrew Gall
- Laboratoire Léon Brillouin (CEA-CNRS), CEA-Saclay, 91191 Gif-sur-Yvette Cedex, France, and Service de Biophysique des Fonctions Membranaires, DBJC/CEA and URA CNRS 2096, CEA-Saclay, 91191 Gif-sur-Yvette Cedex, France
| | - Jérôme Seguin
- Laboratoire Léon Brillouin (CEA-CNRS), CEA-Saclay, 91191 Gif-sur-Yvette Cedex, France, and Service de Biophysique des Fonctions Membranaires, DBJC/CEA and URA CNRS 2096, CEA-Saclay, 91191 Gif-sur-Yvette Cedex, France
| | - Bruno Robert
- Laboratoire Léon Brillouin (CEA-CNRS), CEA-Saclay, 91191 Gif-sur-Yvette Cedex, France, and Service de Biophysique des Fonctions Membranaires, DBJC/CEA and URA CNRS 2096, CEA-Saclay, 91191 Gif-sur-Yvette Cedex, France
| | - Marie-Claire Bellissent-Funel
- Laboratoire Léon Brillouin (CEA-CNRS), CEA-Saclay, 91191 Gif-sur-Yvette Cedex, France, and Service de Biophysique des Fonctions Membranaires, DBJC/CEA and URA CNRS 2096, CEA-Saclay, 91191 Gif-sur-Yvette Cedex, France
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Frolov D, Gall A, Lutz M, Robert B. Structural Asymmetry of Bacterial Reaction Centers: A Qy Resonant Raman Study of the Monomer Bacteriochlorophylls. J Phys Chem A 2002. [DOI: 10.1021/jp0133586] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Dmitrij Frolov
- Service de Biophysique des Fonctions Membranaires, DBJ̇C/CEA and URA 2096/CNRS, CEA-Saclay, F-91191 Gif-sur-Yvette, France
| | - Andrew Gall
- Service de Biophysique des Fonctions Membranaires, DBJ̇C/CEA and URA 2096/CNRS, CEA-Saclay, F-91191 Gif-sur-Yvette, France
| | - Marc Lutz
- Service de Biophysique des Fonctions Membranaires, DBJ̇C/CEA and URA 2096/CNRS, CEA-Saclay, F-91191 Gif-sur-Yvette, France
| | - Bruno Robert
- Service de Biophysique des Fonctions Membranaires, DBJ̇C/CEA and URA 2096/CNRS, CEA-Saclay, F-91191 Gif-sur-Yvette, France
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Abstract
Depression following stroke is common. Although it is highlighted as an issue in stroke guidelines, guidance on diagnosis or management is not given. This paper presents the original research from a literature review of Medline and the Cochrane Database on stroke and depression, and discusses some of the clinical implications of the findings.
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Affiliation(s)
- A Gall
- Department of Rehabilitation Medicine, Woodend Hospital, Aberdeen AB15 6XS
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Gall A, Dellerue S, Lapouge K, Robert B, Bellissent-Funel MC. Small angle neutron scattering measurements on the membrane protein subunit B777 in a detergent microemulsion. Biopolymers 2001; 58:231-4. [PMID: 11169383 DOI: 10.1002/1097-0282(200103)58:3<231::aid-bip1000>3.0.co;2-#] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- A Gall
- Laboratoire Léon Brillouin (CEA-CNRS), CEA/Saclay, 91191 Gif-sur-Yvette Cedex, France.
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