Background: Fourier-transform infrared (FT-IR) spectrometry has been used to measure small molecu... more Background: Fourier-transform infrared (FT-IR) spectrometry has been used to measure small molecules in plasma. We wished to extend this use to measurement of plasma proteins. Methods: We analyzed plasma proteins, glucose, lactate, and urea in 49 blood samples from 35 healthy subjects and 14 patients. For determining the concentration of each biomolecule, the method used the following steps: (a) The biomolecule was sought for which the correlation between spectral range areas of plasma FT-IR spectra and concentrations determined by comparison method was greatest. (b) The IR absorption of the biomolecule at the most characteristic spectral range was calculated by analyzing pure samples of known concentrations. (c) The plasma concentration of the biomolecule was determined using the FT-IR absorption of the pure compound and the integration value obtained for the plasma FT-IR spectra. (d) The spectral contribution of the biomolecule was subtracted from the plasma FT-IR spectra, and the...
Investigated fibres are A B Na2 C (Fe 2+ 2.5Mg0.5) C Fe 3+ 2 T Si8O22 W (OH)2 Riebeckitic amphi... more Investigated fibres are A B Na2 C (Fe 2+ 2.5Mg0.5) C Fe 3+ 2 T Si8O22 W (OH)2 Riebeckitic amphiboles. Textures of fibres are quantified by image analysis on SEM micro-photographs. Increasing amount of fibres induces a general increasing toxicity, whose rate, however, progressively decreases. Fibres are well separated at low-concentrations (< 10 mg/L), but agglomerate for higher concentrations (≥ 10 mg/L). The agglomeration of fibres could have a significant role in controlling the toxicity of asbestos.
Infrared (IR) spectroscopy is at the crossroads , with the requirement to compete with cutting-ed... more Infrared (IR) spectroscopy is at the crossroads , with the requirement to compete with cutting-edge technologies in biosciences, mostly based on analytical performances dealing with the super-resolutions: time, lateral/spatial, and contrast. IR microscopy is diffraction limited in most cases, thus not accessing to high lateral/spatial resolutions. Additionally, it has a poor signal-to-noise ratio on a single scan, thus requiring long-lasting acquisitions that are not suitable to analyze ns-lasting biochemical events. However, it is unique because it provides a broad global chemical information of the sample contents. It is also unique because it does not require heavy sample preparation nor labeling and can be coupled to other techniques (multimodality). Finally, it is again unique because it provides quantitative measurements, thus suitable for 1D to 4D data exploitation procedures. This short review shows that IR spectroscopy will be certainly subjected to a second century of innovations, maintaining its influence in the panorama of cutting-edge analytical techniques.
The study investigated blood markers allowing discriminating physiological responses to on-water ... more The study investigated blood markers allowing discriminating physiological responses to on-water rowing races, notably regarding training volume of athletes and race duration. College (COL) and national (NAT) rowers performed a 1000- or 2000-m race. Capillary blood samples obtained before and post-race allowed an analysis of a wide range of serum parameters. COL rowers had a lower rowing experience and training volume than NAT. Races induced a higher lactate concentration increase in NAT compared to COL (10.45 ± 0.45 vs 13.05 ± 0.60; p ¼ 0.001). Race distance (2000 vs. 1000 m) induced a higher increase in fatty acids (0.81 ± 0.31 vs +0.67 ± 0. 41; p ¼ 0.05) and triglycerides concentration in NAT (0.33 ± 0.07 vs 0.15 ± 0.09; p ¼ 0.01), but remained comparable between NAT and COL for the 1000-m races. Amino acids concentrations increased in NAT (0.19 ± 0.03, p ¼ 0.01), but urea concentration increased only for NAT rowers having performed the 2000-m race (0.72 ± 0.22, p ¼ 0.05). Transf...
We show that sufficient concentrations of gold nanoparticles produced by an original synthesis me... more We show that sufficient concentrations of gold nanoparticles produced by an original synthesis method in EMT-6 and CT-26 cancer cells make it possible to detect the presence, necrosis and proliferation of such cells after inoculation in live mice. We first demonstrated that the nanoparticles do not interfere with the proliferation process. Then, we observed significant differences in the tumor evolution and the angiogenesis process after shallow and deep inoculation. A direct comparison with pathology optical images illustrates the effectiveness of this approach.
In the 1990s, Fourier transform infrared (FTIR) imaging arrived as an analytical tool for the bio... more In the 1990s, Fourier transform infrared (FTIR) imaging arrived as an analytical tool for the biological sciences. However, major limitations have appeared with respect to modern techniques of clinical imaging; slow acquisition of data, diffraction limitations, inability to image living biosystems, and weak sensitivity of detectors. Recent technological developments have demonstrated that FTIR imaging can be used to image living biosamples at the surface of specific crystals, lateral resolution can reach 100 nm without diffraction limits, and realtime imaging is accessible. These analytical improvements, in conjunction with industrial efforts in providing a new generation of high photon flux IR sources and more sensitive detectors, will give FTIR imaging a 'second chance' to be introduced into the clinic.
Abstract The purpose of this study was to apply two-dimensional (2D) correlation Fourier-transfor... more Abstract The purpose of this study was to apply two-dimensional (2D) correlation Fourier-transform infrared (FT-IR) spectrometry to sets of plasma spectra obtained during a physical exercise. Seven male swimmers performed a maximal 400 m test in a 25 m swimming pool. On three other tests, the first 100, 200, and 300 m were swam on the same velocity basis of the 400 m test. 2D correlation spectra were obtained from blood samples taken at rest and after the 100, 200, 300, and 400 m tests. Exercise-induced changes in plasma concentrations and plasma spectra absorptions (νasCH3, νasCH2, νCO, νN–H, δNH2, and νCOO−) were compared to Z-values (correlation peak intensities) found on 2D correlation spectra. During exercise, linear changes were found for glucose, albumin (increases), triglycerides, and fatty acyl moieties (decreases), while lactate and amino-acids increased exponentially, and glycerol increased after 200 m (delayed). Asynchronous 2D-COS highlighted qualitative changes in fatty acid metabolism specifically related to performance (fatty acid selectivity), and allowed to distinguish the origin of urea formation between protein catabolism and amino-acid metabolism. This study has provided further evidence that 2D-FT-IR spectrometry may be used on complex biological samples, such as plasma.
BORDEAUX and TALENCE, FRANCE This study is the first to assess the analytic potential of Fourier-... more BORDEAUX and TALENCE, FRANCE This study is the first to assess the analytic potential of Fourier-transform infrared (FT-IR) spectroscopy in determining exercise-induced metabolic changes, such as glucose and lactate serum concentrations, with single 50 µL blood microsamples. One-hundred ninety-eight capillary blood samples were taken at rest (rest serum) and after rowing exercises at different intensities (exercise serum) to obtain a wide range of lactate concentrations. A quantitative method is described with FT-IR spectroscopy involving only dilution and dessiccation of serum samples. Within serum spectra, an absorption band was strongly specific of glucose (1033 cm-1) that allowed the determination of its concentration (r = 0.97; P < .001 with reference values). Once we had substrated measured glucose absorption in serum spectra, one other absorption band seemed to be specific for lactate (1127 cm-1), which allowed the determination of the concentration of this metabolite (r = 0.96; P < .001 with reference values). The convenience of a capillary blood sampling with the strong accuracy of FT-IR measurements is of particular interest for medicinal and biologic concerns. (
lead to a worsening of the patient's condition. Subtle characterization and monitoring of the phy... more lead to a worsening of the patient's condition. Subtle characterization and monitoring of the physiologic situation of patients with metabolic pathologies is a crucial problem in optimizing therapy. A global biochemical vision of this situation is necessary and cannot be summarized by the determination of a limited number of metabolic concentrations. Among all the physicochemical analytic methods that allow biochemical or metabolic sample characterization, only two provide a global vision of the sample-magnetic resonance and FT-IR spectrometries. Every organic molecule exhibits absorption spectra in the mid-infrared region (4000 to 500 cm-1). Therefore FT-IR plasma spectra should contain the whole sample metabolic information. Recent developments (infrared sources, detectors, Fourier transformation) have shown this technique to be precise and highly reproducible for biologic sample analysis. 1 Defined absorption regions (Fig 1, Table I) are known to be characteristic of some metabolites, 2,3 as Differentiation of populations with different physiologic profiles by plasma Fourier-transform infrared spectra classification CYRIL PETIBOIS, GEORGES CAZORLA, HENRI GIN, and GÉRARD DÉLÉRIS BORDEAUX and TALENCE, FRANCE The pathologic condition of a patient presenting a metabolic disease can change rapidly, and a variety of pathologic conditions are possible. Plasma Fourier-transform infrared (FT-IR) spectra were used to differentiate patients with type 1 diabetes, healthy subjects, and endurance-trained rowers. Analytic and classification methods that use the same plasma FT-IR spectra are described. Complete spectra (4000 to 500 cm-1) classifications led to a differentiation between most patients with type 1 diabetes and other subjects but not between control and trained subjects. Classification of defined absorption regions of spectra allowed different metabolic distinctions between populations. These were performed on the amide I and II absorption regions of proteins (1720 to 1480 cm-1); on the ν=CH, ν as CH 2 , and ν as CH 3 absorption regions of lipids (3020 to 2880 cm-1); and on the νC-O absorption region of saccharides (1300 to 900 cm-1). A classification that uses a combination of four absorption regions-ν=CH (3020 to 3000 cm-1), ν as CH 3 (3000 to 2950 cm-1), νC-O (amide I: 1720 to 1600 cm-1), and νC-O (carbonyle: 1300 to 900 cm-1)-led to the formation of three exclusive clusters that comprised the defined populations. FT-IR spectroscopy is an exciting technique that allows a versatile approach to biologic samples from which analytic and statistical methods might be used for metabolic profile characterization and evaluation.
FT-IR spectrometry has proved to be a useful tool for determining a series of plasma molecular co... more FT-IR spectrometry has proved to be a useful tool for determining a series of plasma molecular concentrations. Dedicated experiments were first performed to test the analytical performance that could be obtained by FT-IR spectrometry using a synthesized N3-peptide exhibiting a -N3 absorption centered at 2110 cm(-1), a spectral region where no organic material of biological samples absorbs. Further, we investigated whether this technology was able to allow quantification of metabolic parameters (glucose and lactic acid) within plasma, cells, and tissues as an alternative method to the &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;quot;classical&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;quot; biochemical approaches, which require sophisticated biological material treatment and expensive reagents. For this purpose we used a series of plasma samples to determine glucose and lactic acid concentrations, which are common markers of cancer growth. We compared the results of the main spectral data treatments commonly achieved for FT-IR data analysis, such as univariate (Beer-Lambert) or multivariate (PLS) calibrations, as well as the deconvolution of the spectral interval of interest (1200-900 cm(-1)). No significant differences were found regarding the analytical performances of these methods. Spectral deconvolution was finally undertaken on cultured and on xenografted cells (U87 glial cells implied in human gliomas) to determine glucose and lactic acid concentrations. In this case, qualification was allowed by FT-IR imaging on the cellular models since biochemical approaches are not efficient to reach metabolic concentrations at the cellular level while keeping tissue organization.
successive and cumulative alterations in metabolism, which become chronic during training. The on... more successive and cumulative alterations in metabolism, which become chronic during training. The onset of this process is a biochemical alteration in carbohydrate (saccharide) metabolism. During endurance exercises, the amount of saccharide chains from two blood glycoproteins (α2-macroglobulin and α1-acid glycoprotein) was found to have decreased, i.e. concentrations of these proteins remained unchanged but their quality changed. These saccharide chains were probably used for burning liver glycogen stores during exercise. This step was followed by alterations in lipid metabolism. The most relevant aspect of this step was that the mean chain length of blood fatty acids decreased, i.e. the same amount of fatty acids were found within the blood, but overtrained individuals presented shorter fatty acids than well-trained individuals. This suggests that alterations appeared in the liver synthesis of long-chain fatty acids or that higher peroxidation of blood lipoparticles occurred. For the final step of this overtraining process, it was found that these dysfunctions in carbohydrate/lipid metabolism led to the higher use of amino acids, which probably resulted from protein catabolism. The evolution of three protein concentrations (α1-acid glycoprotein, α2-macroglobulin and IgG3) correlated with this amino acid concentration increase, suggesting a specific catabolism of these proteins. At this time only, overtraining was clinically diagnosed through conventional symptoms. Therefore, this process described successive alterations in exercise metabolism that shifted from the main energetic stores of exercise (carbohydrates and lipids) towards molecular pools (proteins) normally not substantially used for the energetic supply of skeletal muscles. Now, a general biochemical model of the overtraining process may be proposed which includes most of the previously identified metabolic hypotheses.
Fourier-transform infrared (FTIR) synchrotron radiation (SR) microspectroscopy is a powerful mole... more Fourier-transform infrared (FTIR) synchrotron radiation (SR) microspectroscopy is a powerful molecular probe of biological samples at cellular resolution (<10 mm). As the brilliance of SR is 100-1000 times higher than that of a conventional Globar source, FTIR microscopes are now available in almost all advanced SR facilities around the world. However, in spite of this superior performance, the expected advances in IR SR microscopy have not yet been realised, particularly with regard to bio-analytical studies of single cells and soft tissues. In recent decades solid-state array detectors have revolutionized the fields of molecular spectroscopy and chemical imaging, and now new IR focal plane array detectors implemented at ultra-bright SR facilities will extend the performance and overcome the existing limitations, possibly allowing IR SR instrumentation to achieve the highest sensitivity and resolution of molecular imaging. The impact of IR imaging on large tissue area and the complexity of the analysis are discussed. In view of the high brilliance of SR sources, a comparison of published microscope images is given. Finally, it is briefly outlined how an optimized combination of IR instrumentation and SR optical systems could reach the expected advantages of a SR-based FTIR imaging system.
The Journal of Clinical Endocrinology & Metabolism, 2004
The objective of this study was to describe long-term detraining effects on lipid profile in prev... more The objective of this study was to describe long-term detraining effects on lipid profile in previously highly endurancetrained athletes. The study design was longitudinal, with a 2-yr follow-up study of changes in lipid profile during hard training and detraining. Ten subjects trained for 2 yr (22 h/wk; two 47-wk training periods with a 5-wk recovery period), and the 10 others stopped training after wk 47. Main blood lipid profile parameters, energy intake, and body composition were measured at baseline (wk 1) and at wk 24, 47, 52, 76, and 99. Although food caloric intake was reduced (2411 ؎ 256 vs. 5697 ؎ 455 kcal/d, detraining vs. training), detraining induced a decrease in high density lipoprotein cholesterol and increases in fat mass (by 6.5 ؎ 1.1 kg), body mass index, leptin, low density lipoprotein cholesterol, low density lipoprotein/ high density lipoprotein ratio, and apolipoprotein B, although insulin resistance (determined by homeostasis model assessment) stabilization had previously occurred. Further disorders appeared in triglycerides (TG) metabolism during detraining, with a persistent increase in TG (from 1.0 ؎ 0.3 to 1.4 ؎ 0.3 mmol/liter), whereas glycerol decreased (from 88 ؎ 9 to 73 ؎ 8 mol/liter), and very low density lipoprotein-TG, chylomicrons, and apolipoprotein C 3 remained stable. Plasma lipoprotein lipase activity decreased whereas hepatic lipase activity remained stable. As well as a rapid loss of endurancetraining benefits for the cholesterolemic profile, detraining also induced disorders in TG metabolism, possibly as a result of the elevated TG turnover acquired with long-term hard training. (J Clin Endocrinol Metab 89: 3377-3384, 2004) Abbreviations: Apo, Apolipoprotein; BMI, body mass index; HDL-C, high density lipoprotein cholesterol; HL, hepatic lipase; LDL-C, low density lipoprotein cholesterol; LPL, lipoprotein lipase; Pl-LPL, plasma lipoprotein lipase; RER, respective respiratory exchange ratio; TC, total cholesterol; TG, triglycerides; VLDL, very low density lipoprotein; VCO 2 , CO 2 volume; VO 2 max, maximal oxygen consumption. JCEM is published monthly by The Endocrine Society (http://www. endo-society.org), the foremost professional society serving the endocrine community.
Tumor ischemia participates in angiogenesis and cancer progression through cellular responses to ... more Tumor ischemia participates in angiogenesis and cancer progression through cellular responses to hypoxia and nutrient deprivation. However, the contribution of amino acids limitation to this process remains poorly understood. Using serum-free cell culture conditions, we tested the impact of L-glutamine deprivation on metabolic and angiogenic responses in A549/8 carcinoma cells. In these cells, lowering glutamine concentration modified the cell cycle distribution and significantly induced apoptosis/necrosis. Although glutamine deprivation led to a HIF-independent increase in VEGF-A mRNA, the corresponding protein level remained low and correlated with the inhibition of protein synthesis and activation of the GCN2/eIF2a pathway. Limitation of glutamine availability also hampers hypoxia-and hypoglycemiainduced VEGF-A protein upregulation. Thus, glutamine deprivation may have no direct effect on VEGF-dependent angiogenesis, compared to hypoxia or to glucose deprivation, and may instead be detrimental to cancer progression by antagonizing ischemia-induced stresses.
We tested the hypothesis that usual exercise oxidative stress strongly affects erythrocytes viabi... more We tested the hypothesis that usual exercise oxidative stress strongly affects erythrocytes viability. A 120-min physical exercise with progressive intensity was used as a model of oxidative stress. FT-IR spectrometry was used to determine structural changes in erythrocyte contents (phospholipids, proteins, lactate, and glucose) from blood samples taken every 20 min. Carbonyl formation from amino acid residues (P Z 0.03) and hemoglobin unfolding (P Z 0.01) could be identified as main protein denaturation markers during oxidative stress. Higher unsaturation level (P Z 0.001) in phospholipids fatty acyl chains were also observed while VO 2 increased (P ! 0.05). The increase in lactacidosis affected primarily hemoglobin unfolding (P Z 0.02). Finally, two distinct cellular events occurred during oxidative stress: 1 e phospholipids peroxidation correlated to VO 2 , but lactacidosis and hemoconcentration remained secondary factors; 2 e hemoglobin denaturation was mainly observed through unfolding and carbonylation, and lactacidosis and hemoconcentration were important contributing factors.
In this contribution we present the design of an original Attenuated Total Reflection (ATR)-based... more In this contribution we present the design of an original Attenuated Total Reflection (ATR)-based device designed for an IR microscope coupled to a FPA detector and optimized for in-vivo cell imaging. The optical element has been designed to perform real time experiments of cell biochemical processes. The device includes a manually removable Ge-crystal that guarantees an ease manipulation during the cell culture and a large flat surface to support the cell growth and the required change of the culture wells. This layout will allow performing sequential ATR IR imaging with the crystal immersed in the culture wells, minimizing contributions due to water vapors in the optical system. Using existing brilliant synchrotron radiation sources this ATR device may collect images at the surface of the Ge crystal at a sub-cellular spatial resolution with a penetration depth of the evanescent wave inside the sample of~500 nm within few seconds. A brief summary of the cellular components that should be detected with such optical device is also presented.
Background. We tested the hypothesis that endurance training may reduce exercise oxidative stress... more Background. We tested the hypothesis that endurance training may reduce exercise oxidative stress damage on erythrocytes. Methods. Fifteen subjects performed a standardized endurance exercise at 75% of maximal oxygen consumption weekly during a 19-week training period. Blood samples taken before and after exercise were analyzed by Fourier transform-infrared (FT-IR) spectrometry to determine exercise-induced change in plasma concentrations and erythrocyte IR absorptions. Results. Training first induced a stabilization of plasma concentration changes during exercise (unchanged for glucose, increased for lactate, triglycerides, glycerol, and fatty acids), whereas erythrocyte phospholipid alterations remained elevated (p Ͻ0.05). Further, training reduced the exercise-induced erythrocyte lactate content increase (νC-O; p Ͻ0.05) and phospholipid alterations (νC-H n and νP ϭ O; p Ͻ0.05) during exercise. These changes paralleled the decrease of exercise-induced hemoconcentration (p Ͻ0.05) and plasma lactate increase (p Ͻ0.05). Conclusions. These correlated changes between plasma and erythrocyte parameters suggest that endurance training reduces erythrocyte susceptibility to oxidative stress. Ć 2005 IMSS.
Background. We tested the hypothesis that endurance over-training could alter the favorable effec... more Background. We tested the hypothesis that endurance over-training could alter the favorable effects of well-tolerated training on lipid profile. Methods. At weeks 1, 6, 15, 26, 36, and 47 of the training program, blood was drawn to test lipid profile of 20 endurance-trained rowers. Diet and caloric intake were controlled. Results. Over-training was diagnosed in five subjects (loss of performance, asthenia, sleep disturbance…) at week 15 and lipid profile of well-trained and over-trained subjects were compared. Training improved cholesterolemic profile and lowered insulin resistance (HOMA-IR: Ϫ39 Ϯ 9%; p ϭ 0.02), and triglycerides concentration (Ϫ30 Ϯ 6%; p ϭ 0.05) in rowers who did not change to demonstrate over-training. Plasma LPL (ϩ29 Ϯ 11%; p ϭ 0.01) and hepatic lipase (ϩ5 Ϯ 3%; p ϭ 0.01) activities increased in this group suggesting higher TG utilization and turnover. After week 15 and regarding the welltrained condition for the five over-trained subjects, VLDL-TG (Ϫ13 Ϯ 7 %; p ϭ 0.03) and Apo-C 3 (Ϫ31 Ϯ 13%; p ϭ 0.01) concentrations decreased, while insulin resistance (ϩ17 Ϯ 7%; p ϭ 0.03) and glycerol concentration (ϩ17 Ϯ 3%; p ϭ 0.01) increased and hepatic lipase activity decreased (Ϫ14 Ϯ 4%; p ϭ 0.01). Conclusion. Over-training was accompanied by alterations in the lipid profile, which appeared to be the consequence of over-training. Ć 2004 IMSS.
Background: Fourier-transform infrared (FT-IR) spectrometry has been used to measure small molecu... more Background: Fourier-transform infrared (FT-IR) spectrometry has been used to measure small molecules in plasma. We wished to extend this use to measurement of plasma proteins. Methods: We analyzed plasma proteins, glucose, lactate, and urea in 49 blood samples from 35 healthy subjects and 14 patients. For determining the concentration of each biomolecule, the method used the following steps: (a) The biomolecule was sought for which the correlation between spectral range areas of plasma FT-IR spectra and concentrations determined by comparison method was greatest. (b) The IR absorption of the biomolecule at the most characteristic spectral range was calculated by analyzing pure samples of known concentrations. (c) The plasma concentration of the biomolecule was determined using the FT-IR absorption of the pure compound and the integration value obtained for the plasma FT-IR spectra. (d) The spectral contribution of the biomolecule was subtracted from the plasma FT-IR spectra, and the...
Investigated fibres are A B Na2 C (Fe 2+ 2.5Mg0.5) C Fe 3+ 2 T Si8O22 W (OH)2 Riebeckitic amphi... more Investigated fibres are A B Na2 C (Fe 2+ 2.5Mg0.5) C Fe 3+ 2 T Si8O22 W (OH)2 Riebeckitic amphiboles. Textures of fibres are quantified by image analysis on SEM micro-photographs. Increasing amount of fibres induces a general increasing toxicity, whose rate, however, progressively decreases. Fibres are well separated at low-concentrations (< 10 mg/L), but agglomerate for higher concentrations (≥ 10 mg/L). The agglomeration of fibres could have a significant role in controlling the toxicity of asbestos.
Infrared (IR) spectroscopy is at the crossroads , with the requirement to compete with cutting-ed... more Infrared (IR) spectroscopy is at the crossroads , with the requirement to compete with cutting-edge technologies in biosciences, mostly based on analytical performances dealing with the super-resolutions: time, lateral/spatial, and contrast. IR microscopy is diffraction limited in most cases, thus not accessing to high lateral/spatial resolutions. Additionally, it has a poor signal-to-noise ratio on a single scan, thus requiring long-lasting acquisitions that are not suitable to analyze ns-lasting biochemical events. However, it is unique because it provides a broad global chemical information of the sample contents. It is also unique because it does not require heavy sample preparation nor labeling and can be coupled to other techniques (multimodality). Finally, it is again unique because it provides quantitative measurements, thus suitable for 1D to 4D data exploitation procedures. This short review shows that IR spectroscopy will be certainly subjected to a second century of innovations, maintaining its influence in the panorama of cutting-edge analytical techniques.
The study investigated blood markers allowing discriminating physiological responses to on-water ... more The study investigated blood markers allowing discriminating physiological responses to on-water rowing races, notably regarding training volume of athletes and race duration. College (COL) and national (NAT) rowers performed a 1000- or 2000-m race. Capillary blood samples obtained before and post-race allowed an analysis of a wide range of serum parameters. COL rowers had a lower rowing experience and training volume than NAT. Races induced a higher lactate concentration increase in NAT compared to COL (10.45 ± 0.45 vs 13.05 ± 0.60; p ¼ 0.001). Race distance (2000 vs. 1000 m) induced a higher increase in fatty acids (0.81 ± 0.31 vs +0.67 ± 0. 41; p ¼ 0.05) and triglycerides concentration in NAT (0.33 ± 0.07 vs 0.15 ± 0.09; p ¼ 0.01), but remained comparable between NAT and COL for the 1000-m races. Amino acids concentrations increased in NAT (0.19 ± 0.03, p ¼ 0.01), but urea concentration increased only for NAT rowers having performed the 2000-m race (0.72 ± 0.22, p ¼ 0.05). Transf...
We show that sufficient concentrations of gold nanoparticles produced by an original synthesis me... more We show that sufficient concentrations of gold nanoparticles produced by an original synthesis method in EMT-6 and CT-26 cancer cells make it possible to detect the presence, necrosis and proliferation of such cells after inoculation in live mice. We first demonstrated that the nanoparticles do not interfere with the proliferation process. Then, we observed significant differences in the tumor evolution and the angiogenesis process after shallow and deep inoculation. A direct comparison with pathology optical images illustrates the effectiveness of this approach.
In the 1990s, Fourier transform infrared (FTIR) imaging arrived as an analytical tool for the bio... more In the 1990s, Fourier transform infrared (FTIR) imaging arrived as an analytical tool for the biological sciences. However, major limitations have appeared with respect to modern techniques of clinical imaging; slow acquisition of data, diffraction limitations, inability to image living biosystems, and weak sensitivity of detectors. Recent technological developments have demonstrated that FTIR imaging can be used to image living biosamples at the surface of specific crystals, lateral resolution can reach 100 nm without diffraction limits, and realtime imaging is accessible. These analytical improvements, in conjunction with industrial efforts in providing a new generation of high photon flux IR sources and more sensitive detectors, will give FTIR imaging a 'second chance' to be introduced into the clinic.
Abstract The purpose of this study was to apply two-dimensional (2D) correlation Fourier-transfor... more Abstract The purpose of this study was to apply two-dimensional (2D) correlation Fourier-transform infrared (FT-IR) spectrometry to sets of plasma spectra obtained during a physical exercise. Seven male swimmers performed a maximal 400 m test in a 25 m swimming pool. On three other tests, the first 100, 200, and 300 m were swam on the same velocity basis of the 400 m test. 2D correlation spectra were obtained from blood samples taken at rest and after the 100, 200, 300, and 400 m tests. Exercise-induced changes in plasma concentrations and plasma spectra absorptions (νasCH3, νasCH2, νCO, νN–H, δNH2, and νCOO−) were compared to Z-values (correlation peak intensities) found on 2D correlation spectra. During exercise, linear changes were found for glucose, albumin (increases), triglycerides, and fatty acyl moieties (decreases), while lactate and amino-acids increased exponentially, and glycerol increased after 200 m (delayed). Asynchronous 2D-COS highlighted qualitative changes in fatty acid metabolism specifically related to performance (fatty acid selectivity), and allowed to distinguish the origin of urea formation between protein catabolism and amino-acid metabolism. This study has provided further evidence that 2D-FT-IR spectrometry may be used on complex biological samples, such as plasma.
BORDEAUX and TALENCE, FRANCE This study is the first to assess the analytic potential of Fourier-... more BORDEAUX and TALENCE, FRANCE This study is the first to assess the analytic potential of Fourier-transform infrared (FT-IR) spectroscopy in determining exercise-induced metabolic changes, such as glucose and lactate serum concentrations, with single 50 µL blood microsamples. One-hundred ninety-eight capillary blood samples were taken at rest (rest serum) and after rowing exercises at different intensities (exercise serum) to obtain a wide range of lactate concentrations. A quantitative method is described with FT-IR spectroscopy involving only dilution and dessiccation of serum samples. Within serum spectra, an absorption band was strongly specific of glucose (1033 cm-1) that allowed the determination of its concentration (r = 0.97; P < .001 with reference values). Once we had substrated measured glucose absorption in serum spectra, one other absorption band seemed to be specific for lactate (1127 cm-1), which allowed the determination of the concentration of this metabolite (r = 0.96; P < .001 with reference values). The convenience of a capillary blood sampling with the strong accuracy of FT-IR measurements is of particular interest for medicinal and biologic concerns. (
lead to a worsening of the patient's condition. Subtle characterization and monitoring of the phy... more lead to a worsening of the patient's condition. Subtle characterization and monitoring of the physiologic situation of patients with metabolic pathologies is a crucial problem in optimizing therapy. A global biochemical vision of this situation is necessary and cannot be summarized by the determination of a limited number of metabolic concentrations. Among all the physicochemical analytic methods that allow biochemical or metabolic sample characterization, only two provide a global vision of the sample-magnetic resonance and FT-IR spectrometries. Every organic molecule exhibits absorption spectra in the mid-infrared region (4000 to 500 cm-1). Therefore FT-IR plasma spectra should contain the whole sample metabolic information. Recent developments (infrared sources, detectors, Fourier transformation) have shown this technique to be precise and highly reproducible for biologic sample analysis. 1 Defined absorption regions (Fig 1, Table I) are known to be characteristic of some metabolites, 2,3 as Differentiation of populations with different physiologic profiles by plasma Fourier-transform infrared spectra classification CYRIL PETIBOIS, GEORGES CAZORLA, HENRI GIN, and GÉRARD DÉLÉRIS BORDEAUX and TALENCE, FRANCE The pathologic condition of a patient presenting a metabolic disease can change rapidly, and a variety of pathologic conditions are possible. Plasma Fourier-transform infrared (FT-IR) spectra were used to differentiate patients with type 1 diabetes, healthy subjects, and endurance-trained rowers. Analytic and classification methods that use the same plasma FT-IR spectra are described. Complete spectra (4000 to 500 cm-1) classifications led to a differentiation between most patients with type 1 diabetes and other subjects but not between control and trained subjects. Classification of defined absorption regions of spectra allowed different metabolic distinctions between populations. These were performed on the amide I and II absorption regions of proteins (1720 to 1480 cm-1); on the ν=CH, ν as CH 2 , and ν as CH 3 absorption regions of lipids (3020 to 2880 cm-1); and on the νC-O absorption region of saccharides (1300 to 900 cm-1). A classification that uses a combination of four absorption regions-ν=CH (3020 to 3000 cm-1), ν as CH 3 (3000 to 2950 cm-1), νC-O (amide I: 1720 to 1600 cm-1), and νC-O (carbonyle: 1300 to 900 cm-1)-led to the formation of three exclusive clusters that comprised the defined populations. FT-IR spectroscopy is an exciting technique that allows a versatile approach to biologic samples from which analytic and statistical methods might be used for metabolic profile characterization and evaluation.
FT-IR spectrometry has proved to be a useful tool for determining a series of plasma molecular co... more FT-IR spectrometry has proved to be a useful tool for determining a series of plasma molecular concentrations. Dedicated experiments were first performed to test the analytical performance that could be obtained by FT-IR spectrometry using a synthesized N3-peptide exhibiting a -N3 absorption centered at 2110 cm(-1), a spectral region where no organic material of biological samples absorbs. Further, we investigated whether this technology was able to allow quantification of metabolic parameters (glucose and lactic acid) within plasma, cells, and tissues as an alternative method to the &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;quot;classical&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;quot; biochemical approaches, which require sophisticated biological material treatment and expensive reagents. For this purpose we used a series of plasma samples to determine glucose and lactic acid concentrations, which are common markers of cancer growth. We compared the results of the main spectral data treatments commonly achieved for FT-IR data analysis, such as univariate (Beer-Lambert) or multivariate (PLS) calibrations, as well as the deconvolution of the spectral interval of interest (1200-900 cm(-1)). No significant differences were found regarding the analytical performances of these methods. Spectral deconvolution was finally undertaken on cultured and on xenografted cells (U87 glial cells implied in human gliomas) to determine glucose and lactic acid concentrations. In this case, qualification was allowed by FT-IR imaging on the cellular models since biochemical approaches are not efficient to reach metabolic concentrations at the cellular level while keeping tissue organization.
successive and cumulative alterations in metabolism, which become chronic during training. The on... more successive and cumulative alterations in metabolism, which become chronic during training. The onset of this process is a biochemical alteration in carbohydrate (saccharide) metabolism. During endurance exercises, the amount of saccharide chains from two blood glycoproteins (α2-macroglobulin and α1-acid glycoprotein) was found to have decreased, i.e. concentrations of these proteins remained unchanged but their quality changed. These saccharide chains were probably used for burning liver glycogen stores during exercise. This step was followed by alterations in lipid metabolism. The most relevant aspect of this step was that the mean chain length of blood fatty acids decreased, i.e. the same amount of fatty acids were found within the blood, but overtrained individuals presented shorter fatty acids than well-trained individuals. This suggests that alterations appeared in the liver synthesis of long-chain fatty acids or that higher peroxidation of blood lipoparticles occurred. For the final step of this overtraining process, it was found that these dysfunctions in carbohydrate/lipid metabolism led to the higher use of amino acids, which probably resulted from protein catabolism. The evolution of three protein concentrations (α1-acid glycoprotein, α2-macroglobulin and IgG3) correlated with this amino acid concentration increase, suggesting a specific catabolism of these proteins. At this time only, overtraining was clinically diagnosed through conventional symptoms. Therefore, this process described successive alterations in exercise metabolism that shifted from the main energetic stores of exercise (carbohydrates and lipids) towards molecular pools (proteins) normally not substantially used for the energetic supply of skeletal muscles. Now, a general biochemical model of the overtraining process may be proposed which includes most of the previously identified metabolic hypotheses.
Fourier-transform infrared (FTIR) synchrotron radiation (SR) microspectroscopy is a powerful mole... more Fourier-transform infrared (FTIR) synchrotron radiation (SR) microspectroscopy is a powerful molecular probe of biological samples at cellular resolution (<10 mm). As the brilliance of SR is 100-1000 times higher than that of a conventional Globar source, FTIR microscopes are now available in almost all advanced SR facilities around the world. However, in spite of this superior performance, the expected advances in IR SR microscopy have not yet been realised, particularly with regard to bio-analytical studies of single cells and soft tissues. In recent decades solid-state array detectors have revolutionized the fields of molecular spectroscopy and chemical imaging, and now new IR focal plane array detectors implemented at ultra-bright SR facilities will extend the performance and overcome the existing limitations, possibly allowing IR SR instrumentation to achieve the highest sensitivity and resolution of molecular imaging. The impact of IR imaging on large tissue area and the complexity of the analysis are discussed. In view of the high brilliance of SR sources, a comparison of published microscope images is given. Finally, it is briefly outlined how an optimized combination of IR instrumentation and SR optical systems could reach the expected advantages of a SR-based FTIR imaging system.
The Journal of Clinical Endocrinology & Metabolism, 2004
The objective of this study was to describe long-term detraining effects on lipid profile in prev... more The objective of this study was to describe long-term detraining effects on lipid profile in previously highly endurancetrained athletes. The study design was longitudinal, with a 2-yr follow-up study of changes in lipid profile during hard training and detraining. Ten subjects trained for 2 yr (22 h/wk; two 47-wk training periods with a 5-wk recovery period), and the 10 others stopped training after wk 47. Main blood lipid profile parameters, energy intake, and body composition were measured at baseline (wk 1) and at wk 24, 47, 52, 76, and 99. Although food caloric intake was reduced (2411 ؎ 256 vs. 5697 ؎ 455 kcal/d, detraining vs. training), detraining induced a decrease in high density lipoprotein cholesterol and increases in fat mass (by 6.5 ؎ 1.1 kg), body mass index, leptin, low density lipoprotein cholesterol, low density lipoprotein/ high density lipoprotein ratio, and apolipoprotein B, although insulin resistance (determined by homeostasis model assessment) stabilization had previously occurred. Further disorders appeared in triglycerides (TG) metabolism during detraining, with a persistent increase in TG (from 1.0 ؎ 0.3 to 1.4 ؎ 0.3 mmol/liter), whereas glycerol decreased (from 88 ؎ 9 to 73 ؎ 8 mol/liter), and very low density lipoprotein-TG, chylomicrons, and apolipoprotein C 3 remained stable. Plasma lipoprotein lipase activity decreased whereas hepatic lipase activity remained stable. As well as a rapid loss of endurancetraining benefits for the cholesterolemic profile, detraining also induced disorders in TG metabolism, possibly as a result of the elevated TG turnover acquired with long-term hard training. (J Clin Endocrinol Metab 89: 3377-3384, 2004) Abbreviations: Apo, Apolipoprotein; BMI, body mass index; HDL-C, high density lipoprotein cholesterol; HL, hepatic lipase; LDL-C, low density lipoprotein cholesterol; LPL, lipoprotein lipase; Pl-LPL, plasma lipoprotein lipase; RER, respective respiratory exchange ratio; TC, total cholesterol; TG, triglycerides; VLDL, very low density lipoprotein; VCO 2 , CO 2 volume; VO 2 max, maximal oxygen consumption. JCEM is published monthly by The Endocrine Society (http://www. endo-society.org), the foremost professional society serving the endocrine community.
Tumor ischemia participates in angiogenesis and cancer progression through cellular responses to ... more Tumor ischemia participates in angiogenesis and cancer progression through cellular responses to hypoxia and nutrient deprivation. However, the contribution of amino acids limitation to this process remains poorly understood. Using serum-free cell culture conditions, we tested the impact of L-glutamine deprivation on metabolic and angiogenic responses in A549/8 carcinoma cells. In these cells, lowering glutamine concentration modified the cell cycle distribution and significantly induced apoptosis/necrosis. Although glutamine deprivation led to a HIF-independent increase in VEGF-A mRNA, the corresponding protein level remained low and correlated with the inhibition of protein synthesis and activation of the GCN2/eIF2a pathway. Limitation of glutamine availability also hampers hypoxia-and hypoglycemiainduced VEGF-A protein upregulation. Thus, glutamine deprivation may have no direct effect on VEGF-dependent angiogenesis, compared to hypoxia or to glucose deprivation, and may instead be detrimental to cancer progression by antagonizing ischemia-induced stresses.
We tested the hypothesis that usual exercise oxidative stress strongly affects erythrocytes viabi... more We tested the hypothesis that usual exercise oxidative stress strongly affects erythrocytes viability. A 120-min physical exercise with progressive intensity was used as a model of oxidative stress. FT-IR spectrometry was used to determine structural changes in erythrocyte contents (phospholipids, proteins, lactate, and glucose) from blood samples taken every 20 min. Carbonyl formation from amino acid residues (P Z 0.03) and hemoglobin unfolding (P Z 0.01) could be identified as main protein denaturation markers during oxidative stress. Higher unsaturation level (P Z 0.001) in phospholipids fatty acyl chains were also observed while VO 2 increased (P ! 0.05). The increase in lactacidosis affected primarily hemoglobin unfolding (P Z 0.02). Finally, two distinct cellular events occurred during oxidative stress: 1 e phospholipids peroxidation correlated to VO 2 , but lactacidosis and hemoconcentration remained secondary factors; 2 e hemoglobin denaturation was mainly observed through unfolding and carbonylation, and lactacidosis and hemoconcentration were important contributing factors.
In this contribution we present the design of an original Attenuated Total Reflection (ATR)-based... more In this contribution we present the design of an original Attenuated Total Reflection (ATR)-based device designed for an IR microscope coupled to a FPA detector and optimized for in-vivo cell imaging. The optical element has been designed to perform real time experiments of cell biochemical processes. The device includes a manually removable Ge-crystal that guarantees an ease manipulation during the cell culture and a large flat surface to support the cell growth and the required change of the culture wells. This layout will allow performing sequential ATR IR imaging with the crystal immersed in the culture wells, minimizing contributions due to water vapors in the optical system. Using existing brilliant synchrotron radiation sources this ATR device may collect images at the surface of the Ge crystal at a sub-cellular spatial resolution with a penetration depth of the evanescent wave inside the sample of~500 nm within few seconds. A brief summary of the cellular components that should be detected with such optical device is also presented.
Background. We tested the hypothesis that endurance training may reduce exercise oxidative stress... more Background. We tested the hypothesis that endurance training may reduce exercise oxidative stress damage on erythrocytes. Methods. Fifteen subjects performed a standardized endurance exercise at 75% of maximal oxygen consumption weekly during a 19-week training period. Blood samples taken before and after exercise were analyzed by Fourier transform-infrared (FT-IR) spectrometry to determine exercise-induced change in plasma concentrations and erythrocyte IR absorptions. Results. Training first induced a stabilization of plasma concentration changes during exercise (unchanged for glucose, increased for lactate, triglycerides, glycerol, and fatty acids), whereas erythrocyte phospholipid alterations remained elevated (p Ͻ0.05). Further, training reduced the exercise-induced erythrocyte lactate content increase (νC-O; p Ͻ0.05) and phospholipid alterations (νC-H n and νP ϭ O; p Ͻ0.05) during exercise. These changes paralleled the decrease of exercise-induced hemoconcentration (p Ͻ0.05) and plasma lactate increase (p Ͻ0.05). Conclusions. These correlated changes between plasma and erythrocyte parameters suggest that endurance training reduces erythrocyte susceptibility to oxidative stress. Ć 2005 IMSS.
Background. We tested the hypothesis that endurance over-training could alter the favorable effec... more Background. We tested the hypothesis that endurance over-training could alter the favorable effects of well-tolerated training on lipid profile. Methods. At weeks 1, 6, 15, 26, 36, and 47 of the training program, blood was drawn to test lipid profile of 20 endurance-trained rowers. Diet and caloric intake were controlled. Results. Over-training was diagnosed in five subjects (loss of performance, asthenia, sleep disturbance…) at week 15 and lipid profile of well-trained and over-trained subjects were compared. Training improved cholesterolemic profile and lowered insulin resistance (HOMA-IR: Ϫ39 Ϯ 9%; p ϭ 0.02), and triglycerides concentration (Ϫ30 Ϯ 6%; p ϭ 0.05) in rowers who did not change to demonstrate over-training. Plasma LPL (ϩ29 Ϯ 11%; p ϭ 0.01) and hepatic lipase (ϩ5 Ϯ 3%; p ϭ 0.01) activities increased in this group suggesting higher TG utilization and turnover. After week 15 and regarding the welltrained condition for the five over-trained subjects, VLDL-TG (Ϫ13 Ϯ 7 %; p ϭ 0.03) and Apo-C 3 (Ϫ31 Ϯ 13%; p ϭ 0.01) concentrations decreased, while insulin resistance (ϩ17 Ϯ 7%; p ϭ 0.03) and glycerol concentration (ϩ17 Ϯ 3%; p ϭ 0.01) increased and hepatic lipase activity decreased (Ϫ14 Ϯ 4%; p ϭ 0.01). Conclusion. Over-training was accompanied by alterations in the lipid profile, which appeared to be the consequence of over-training. Ć 2004 IMSS.
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