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This study examines the feasibility of using the mid infrared (MIR) spectroscopy for the determination of some parameters in European Emmental cheeses produced in summer from different geographic origins. A total of 72 Emmental cheeses (4 samples from Finland, 6 samples from Germany, 8 samples from Austria, 27 samples from France and 27 samples from Switzerland) were investigated. Total nitrogen (TN), water soluble nitrogen (WSN), non protein nitrogen (NPN), sodium chloride (NaCl) and pH were analysed by the reference methods. The MIR-transmission of the investigated cheeses was measured by a Nicolet Magna 750 IR spectrophotometer in a measurement range between 4000 and 400 cm−1.

Correspondance auteur: Dufour E. E-mail: dufour@enitac.fr; International audience; The potential of mid-infrared and intrinsic fluorescence spectroscopies was investigated for determining the geographic origin of different hard cheeses. Mid-infrared (1700-1500 cm(-1) region), fluorescence emission spectra, following excitation at 250 and 290 nm, and fluorescence excitation spectra following emission at 410 nm were recorded directly on cheese samples. Twelve experimental hard cheeses were made using identical and controlled cheese-making conditions with milks originating from three different regions in Jura (France). The results of factorial discriminant analysis (FDA) performed on the fluorescence and mid-infrared spectra of the experimental cheeses showed a good discrimination of the cheeses. In a second step, 25 Gruyere Protected Denomination of Origin (PDO) cheeses manufactured at different altitudes in Switzerland, i.e., 11 Gruyere PDO cheeses from the lowlands (< 800 m), eight Gruyere PDO cheeses from the highlands (1100-1500 m) and six L'Etivaz PDO cheeses (1500-1850 m) were analysed. Only 80% of correct classification was obtained by applying FDA to the mid-infrared spectra of the investigated cheeses. A better classification (100%) was achieved based on the fluorescence spectra. Front-face fluorescence spectroscopy appeared to be rapid, low cost and efficient for the geographic determination of Gruyere cheeses

The potential of near-infrared (NIR), mid-infrared (MIR) and front-face fluorescence spectroscopies combined with chemometric methods was investigated for discriminating Emmental cheeses from different European geographic origins. A total of 91 Emmental cheeses produced during winter in Austria ( n = 4 ), Finland ( n = 6 ), Germany ( n = 13 ), France ( n = 30 ) and Switzerland ( n = 38 ) were investigated. Cheese samples were classified by factorial discriminant analysis. From NIR, a good classification of cheeses was observed for 89% and 86.8% of the calibration and validation spectral data sets, respectively. The MIR results were comparable to those observed with NIR. Within the 3000–2800 cm−1 region, 84.1% and 85.7% of the cheeses were correctly classified for the calibration and validation data sets, respectively. The classification obtained with the tryptophan fluorescence spectra was considerably lower (only 67.6% and 41.7% for classification and validation spectra, respectively). But tryptophan fluorescence spectra allowed a good discrimination of Emmental cheeses made from raw milk or from thermised milk. Common components and specific weights analysis were performed on the physico-chemical, infrared and tryptophan fluorescence data sets. These results showed that spectroscopic techniques may provide useful fingerprints and allow the identification of Emmental cheeses according to the geographic origin and production conditions.

International audience; Emission and excitation spectra of intrinsic fluorophores present. in milk were used to evaluate changes in milk following thermal treatments in the 57-72 degreesC temperature range from 0.5 min up to 30 min. Alternatively, the concentrations of native alkaline phosphatase, lactoferrin, immunoglobulin G, bovine serum albumin, beta-lactoglobulin, and alpha-lactalbumin were determined in the same samples by enzymatic and immunochemical techniques. As principal component analysis applied to the normalized fluorescence spectra successfully discriminated different milk samples according to the temperature and time of thermal treatment, principal component regression was applied to predict the amounts of the native proteins investigated using fluorescence data. The results showed strong correlations between measured and predicted data for alkaline phosphatase and beta-lactoglobulin. This study has demonstrated that front-face fluorescence spectroscopy has a promising potential to become a rapid and nondestructive analytical technique for the evaluation of physicochemical changes in milk induced by low thermal treatment.

Three different fluorescence spectra were recorded following excitation at 250 nm (aromatic amino acids+nucleic acids, AAA+NA), 316 nm (NADH) and 380 nm (FAD) for 20 type strain collections of lactic acid bacteria (LAB). Evaluation of the data using principal component analysis and factorial discriminant analysis showed a good discrimination of considered LAB at the genus, species and genus-species level. AAA+NA fluorophores showed the highest percentage of good classification. From AAA+NA spectra recorded on LAB isolated from a small-scale facility producing traditional dry sausages, we succeeded to identify 28 of 29 wild strains. This method allowed us to discriminate between Lactobacillus sakei subsp. carnosus and Lactobacillus sakei subsp. sakei. Thus, intrinsic fluorescence is an economical and powerful tool for the identification of wild LAB isolated from meat and meat products.

Mid-infrared (MIR) and front-face fluorescence spectroscopies, coupled with chemo- metric techniques, were investigated for their potential for discriminating Emmental cheeses origi- nating from various geographic origins. A total of 74 Emmental cheeses, produced during summer, from six countries, i.e., Denmark (n = 2), Finland (n = 4), Germany (n = 6), Austria (n =8 ),rance (n = 27) and Switzerland (n = 27) were analysed. Within the 1500-900 cm -1 spectral region, a good classification of samples was obtained for 83.7 and 77% of the calibration and validation data sets, respectively. Within the 3000-2800 cm -1 the classification was considerably worse (only 57.4 and 29.7% for the calibration and validation spectra, respectively). Protein tryptophan and vitamin A fluorescence spectra were recorded directly on cheese samples. Considering tryptophan fluores- cence spectra, a good classification was observed for 76.4 and 63.5% of the calibration and the vali- dation samples, respectively. A better classification was obtained from the vitamin A fluorescence spectra since 93.9 and 90.5% of the calibration and validation spectra, respectively, were correctly classified. Cheeses from Finland and Denmark were well separated using the 1500-900 cm -1 spec- tra and tryptophan or vitamin A fluorescence spectra. Considering cheeses from Germany, 100% of good classification was only obtained with vitamin A spectra. Cheeses from France and Switzerland were generally discriminated, but several samples were incorrectly classified. It was concluded that vitamin A fluorescence spectra may be considered a promising probe for the reliable evaluation of Emmental cheese origin.

In order to investigate the potential of fluorescence spectroscopy to characterise meat emulsions and frankfurters, a split-plot design comprising three factors at three levels each, i.e. fat/lean ratios (0.25, 0.7 and 1.5), chopping speed (1000, 2000 and 3000 rpm) and chopping time (1, 3 and 7 min), was considered. Principal component analysis and hierarchical ascendant clustering performed on the texture attributes and L(*)a(*)b(*) value data sets for the batters and frankfurters showed that a limited number of clusters can be discriminated, mainly according to the chopping conditions. From the fluorescence spectra of batters and frankfurters, the similarity maps defined by principal components 1 and 2 allowed clear discrimination between formulations with a high fat content from those of low fat content, whereas formulations with an intermediate fat content overlapped. Canonical correlation analysis (CCA) showed strong correlations between the batter texture attributes and the batter fluorescence spectra since the first pairs of canonical variates exhibited squared correlation coefficients of 0.88. Moreover, it was shown by CCA that batter fluorescence spectra and frankfurter texture-attributes were highly correlated (r(2)=0.91) for the first canonical variates suggesting that it may be possible to predict the texture of a frankfurter from a fluorescence spectrum recorded on the batter.

The aim of this work was to investigate the selective bactericidal effect of several decontaminating solutions on some spoilage, pathogenic and useful bacteria isolated from a traditional meat workshop. Fourteen decontaminating solutions, i.e., acid, alkaline, osmotic, biocide solutions or their combinations were tested on five bacterial species grown as monospecies biofilms. The solution made of monolaurin (0.075% w/v) and acetic acid at pH 5.4 was the most selective decontaminating solution. It reduced by only 0.2 and 0.4 log Lactobacillus spp. and Staphylococcus carnosus , whereas Pseudomonas fluorescens , Pseudomonas putida and Listeria monocytogenes exhibited reductions of 3.7, 3.2 and 4.2 log, respectively. The acetic solution (pH 5.4) and the solution containing monolaurin (0.075% w/v) and sodium sulfate (12% w/v) were also selective. But their bactericidal effects on Pseudomonas species were relatively small. Four selected solutions were then applied to seven bacterial species grown as multispecies biofilms. The mixture solution of monolaurin (0.075% w/v) and acetic acid at pH 5.4 showed again the best selectivity. Finally, lowering the pH of the acetic solution from 5.4 to 5.2 increased the selective decontamination.

Intrinsic fluorescent properties of muscle tissue were evaluated in order to characterize the different structural components of meat. The combinations of excitation and emission wavelengths showing the best ability to distinguish the 3 components were 290/332 nm for myofiber, 322/440 (or 322/405) nm for fat, and 380/440 nm for connective tissue. Sample orientation and the mincing of meat samples affected fluorescent amplitudes but not the overall shape of the spectra. These emission spectra of meat components were used to make multispectral images to determine whether the 3 components could be distinguished. The results show that auto fluorescence can be used for selective visualization of fat, fiber, and connective tissue on digitized images of meat.

The intrinsic fluorescence of fish muscle was evaluated as a possible rapid and non-destructive method for the monitoring of fish freshness. The fluorescence emission spectra of aromatic-amino-acids+nucleic-acids (excitation: 250 nm, emission: 280–480 nm), tryptophan residues (excitation: 290 nm, emission: 305–400 nm) of proteins and NADH (excitation: 336 nm, emission: 360–600 nm) were recorded on cod, mackerel, salmon and whiting fillets at 1, 5, 8 and 13 days of storage. Principal component analysis and Mahalanobis distance method were applied to the spectral data sets. Considering the mackerel, the similarity map defined by the principal components 1 and 2 showed a discrimination of the aromatic-amino-acids+nucleic-acids spectra recorded after 1 day of storage versus the ones recorded after 5 and 8 days of storage according to the principal component 1. Similar trends were observed for all the fish species and all the fluorophores investigated. It appears that the intrinsic fluorescence spectra could be considered as fingerprints that may allow the discrimination between fresh and aged fish fillets.

The viscoelastic properties and the matrix structures of three different retailed soft cheeses (M1, M2 and M3), for which the manufacturing process was varied, were studied from the surface to the centre of the cheese using dynamic rheology and front-face fluorescence spectroscopy. The storage modulus ( G ′) and the loss modulus ( G ″) values of the samples increased from the surface to the inner part of the cheeses, while strain and tan δ decreased. Protein tryptophan (excitation: 290 nm; emission: 305–400 nm) and vitamin A (emission: 410 nm; excitation: 250–350 nm) spectra were recorded at 20°C in samples cut from the surface to the centre. For each cheese, the data sets containing fluorescence spectra and rheology data were evaluated using multidimensional statistical methods. In addition, the three cheeses were well discriminated by their spectra by applying factorial discriminant analysis. From the tryptophan fluorescence data sets, 94% and 87.7% good classifications were observed for calibration and validation groups, respectively. A better classification (100% and 96% for principal and test samples) was obtained from the vitamin A spectra. Canonical correlation analysis was performed on the rheology and tryptophan fluorescence spectral data sets, and on the rheology and vitamin A fluorescence spectra data sets. The two groups of variables were found to be highly correlated since the squared canonical coefficients for canonical variates 1, 2, 3, 4 were higher than 0.98. These high correlations indicate that cheese rheology is a reflection of its structure at the molecular level.

A novel rapid and non-destructive front-face fluorescence method to quantify furosine and lactulose in heat-treated milk has been developed. The emission fluorescence spectra (305-450 nm) of tryptophans of proteins, and emission and excitation fluorescence spectra of fluo- rescent Maillard-reaction products were recorded directly on milk samples. Principal component analysis (PCA) and principal component regression (PCR) were applied to process the spectra ob- tained. The front-face fluorescence method can give valuable information on the quality of heat- treated milk because it allows the evaluation of furosine and lactulose content simultaneously. The re- sults were well correlated with those of the reference methods. The front-face fluorescence technique is relatively low-cost, rapid and non-destructive and it could replace existing conventional analytical techniques practiced for lactulose and furosine evaluation in dairy products. Milk / heat treatment / front-face fluorescence / tryptophan / Maillard-reaction products / furosine / lactulose

Several lines of evidence have implicated reactive oxygen species (ROS) in the pathogenesis of various degenerative diseases and in organismal ageing. Furthermore, it has been shown recently that the alternative pathway respiration present in plants lowers ROS mitochondrial production. An alternative oxidase (AOXp) also occurs in the filamentous fungus Podospora anserina. We show here that overexpression of this oxidase does not decrease ROS production and has no effect on longevity, mitochondrial stability or ageing in this fungus. In the same way, inactivation of the gene has no effect on these parameters. In contrast, overexpression of the alternative oxidase in the long-lived cox5::BLE mutant, deficient in cytochrome c oxidase, considerably increases ROS production of the mutant. It rescues slow growth rate and female sterility, indicating an improved energy level. This overexpression also restores senescence and mitochondrial DNA instability, demonstrating that these parameters are controlled by the energy level and not by the expression level of the alternative oxidase. We also suggest that expression of this oxidase in organisms naturally devoid of it could rescue respiratory defects resulting from cytochrome pathway dysfunctions.

The aim of this study is to measure displacement fields during an experiment on a structure by using a priori information about its surface representation in a stereoDIC framework. The main goal of the present method is to measure the displacement and strain fields in formalisms completely consistent with the surface description via global stereoDIC. Although the majority of stereoDIC methods provide clouds of 3D displacement vectors associated with clouds of 3D points, which are subsequently interpolated to get continuous fields, the proposed CAD-based stereoDIC allows continuous 3D displacement fields to be measured directly. Therefore, there is a direct link between the measured fields and computational results since common shape and kinematic bases are considered. No additional interpolation or data manipulation is needed with such approaches. One practical example will illustrate the use of this novel technique.

The machinery of mitochondrial DNA (mtDNA) maintenance is only partially characterized and is of wide interest due to its involvement in disease. To identify novel components of this machinery, plus other cellular pathways required for mtDNA viability, we implemented a genome-wide RNAi screen in Drosophila S2 cells, assaying for loss of fluorescence of mtDNA nucleoids stained with the DNA-intercalating agent PicoGreen. In addition to previously characterized components of the mtDNA replication and transcription machineries, positives included many proteins of the cytosolic proteasome and ribosome (but not the mitoribosome), three proteins involved in vesicle transport, some other factors involved in mitochondrial biogenesis or nuclear gene expression, > 30 mainly uncharacterized proteins and most subunits of ATP synthase (but no other OXPHOS complex). ATP synthase knockdown precipitated a burst of mitochondrial ROS production, followed by copy number depletion involving increased mitochondrial turnover, not dependent on the canonical autophagy machinery. Our findings will inform future studies of the apparatus and regulation of mtDNA maintenance, and the role of mitochondrial bioenergetics and signaling in modulating mtDNA copy number. Synopsis An RNAi screen for genes needed in mtDNA copy number maintenance in Drosophila yielded 97 positives, including previously characterized mtDNA maintenance proteins, subunits of the cytoribosome, proteasome, and ATP synthase. An RNAi screen for genes needed in mtDNA copy number maintenance in Drosophila yielded 97 positives. These included previously characterized components of the mtDNA maintenance machinery. Other major classes of positives were the cytoribosome, proteasome, and ATP synthase. ATP synthase deficiency results in increased ROS and activation of mitochondrial turnover by pathway(s) distinct from classical autophagy. An RNAi screen for genes needed in mtDNA copy number maintenance in Drosophila yielded 97 positives, including previously characterized mtDNA maintenance proteins, subunits of the cytoribosome, proteasome, and ATP synthase. © 2014 The Authors. Published under the terms of the CC BY 4.0 license.

Optical aberrations are one of the biases affecting images. Their correction can be performed as a transformation of the image. In this paper, it is proposed to use digital image correlation to calculate the distortion fields. A correlation calculation is performed between a known numerical pattern and a picture of the same pattern printed or etched on a plate. This new procedure is applied to determine the distortion fields of a camera lens. First, a parametric description of the distortion field is used to reduce the degrees of freedom required to describe optical distortions. Second, a non-parametric model based upon splines is used. The distortion fields found by both methods are compared. A resolution analysis is performed for two different procedures (removing the lens between pictures or not). The standard displacement resolution is found to be of the order of 10-2 pixel in the first case, and 2.5 × 10 − 3 pixel in the second case.

Recent epidemiological and laboratory-based studies suggest that the anti-diabetic drug metformin prevents cancer progression. How metformin diminishes tumor growth is not fully understood. In this study, we report that in human cancer cells, metformin inhibits mitochondrial complex I (NADH dehydrogenase) activity and cellular respiration. Metformin inhibited cellular proliferation in the presence of glucose, but induced cell death upon glucose deprivation, indicating that cancer cells rely exclusively on glycolysis for survival in the presence of metformin. Metformin also reduced hypoxic activation of hypoxia-inducible factor 1 (HIF-1). All of these effects of metformin were reversed when the metformin-resistant Saccharomyces cerevisiae NADH dehydrogenase NDI1 was overexpressed. In vivo, the administration of metformin to mice inhibited the growth of control human cancer cells but not those expressing NDI1. Thus, we have demonstrated that metformin's inhibitory effects on cancer progression are cancer cell autonomous and depend on its ability to inhibit mitochondrial complex I. DOI: http://dx.doi.org/10.7554/eLife.02242.001, eLife digest Metformin is widely used to reduce the high blood sugar levels caused by diabetes. Recently, several studies have suggested that patients taking metformin who also develop cancer have tumors that grow more slowly than average. As clinical trials have already started to investigate if metformin is an effective anti-cancer treatment, it is important to understand how it might restrict tumor growth. Researchers have proposed two ways that metformin could affect tumors. First, insulin is known to prompt cancer cells to divide, so the slower rate of tumor growth could just be a side-effect of the metformin reducing the amount of insulin in the blood. Alternatively, metformin could target cancer cells more directly by cutting the energy supply produced by their mitochondria. Metformin has been shown to disrupt complex I of the electron transport chain that is used by cells to generate energy. However, it is not known if disrupting complex I would actually stop cells dividing because they can generate energy in other ways. Wheaton, Weinberg et al. have now demonstrated that metformin does target complex I in cancer cells, and that its effects depend on the amount of glucose available for cells to convert, without involving mitochondria, into energy. When there is plenty of glucose, metformin slows down the rate at which cancer cells divide, which slows down tumor growth. When the cells are deprived of glucose, metformin kills the cells instead. Metformin also inhibits the pathways that regulate hypoxia inducible factors (HIFs), which are part of a system that helps cells to survive low-oxygen conditions, a prominent feature of many tumors. This means that metformin may combat cancer more effectively if used alongside other treatments that reduce the availability of both oxygen and glucose inside cells. Metformin could also potentially treat conditions that are linked to overactive HIFs, such as pulmonary hypertension. DOI: http://dx.doi.org/10.7554/eLife.02242.002

International audience; A new calibration procedure is proposed for a stereovision setup. It uses the object of interest as the calibration target, provided the observed surface has a known de nition (e.g., its CAD model). In a rst step, the transformation matrices needed for the calibration of the setup are determined assuming that the object conforms to its CAD model. Then the 3D shape of the surface of interest is evaluated by deforming the a priori given freeform surface. These two steps are performed via an integrated approach to stereoDIC. The measured 3D shape of a machined Bézier patch is validated against data obtained by a coordinate measuring machine. The feasibility of the calibration method's application to large surfaces is shown with the analysis of a 2-m2 automotive roof panel.

Tryptophan fluorescence spectra of eight different soft cheeses were recorded directly on cheese samples using front-face fluorescence spectroscopy. Discriminant ability of the data was investigated by discriminant analysis. A correct classification was observed for 95% and 92% of the calibration and validation samples, respectively. It was concluded that tryptophan fluorescence spectra enable the identity of individual cheeses to be finger-printed. Canonical correlation analysis was applied to soft-cheese sensory profile data and fluorescence spectral collection in order to measure the link between the two groups of variables measured on the same samples. The two groups of variables were found highly correlated since the squared canonical coefficients for canonical variates 1 and 2 were 0.93 and 0.80, respectively. A subset of four cheeses was investigated closely in order to establish a molecular basis of the discrimination. It was shown that molecular level information may be derived from the fluorescence spectra.

Sixteen semi-hard cheeses varying by their protein (20.2–24.1%), fat (23.7–31.1%) and dry matter (50.2–57.9%) contents were manufactured and ripened in controlled conditions. Fluorescence (vitamin A) and mid-infrared (2780–3000 cm−1 region) spectra were collected on the 16 different cheeses at 1, 21, 51 and 81 days of ripening. The data tables containing the mid-infrared and fluorescence spectra of the different cheeses were analyzed by principal component analysis and canonical correlation analysis methods. The obtained similarity maps showed that it was possible to discriminate the cheeses at the four different ripening times from the infrared and fluorescence spectra. In addition, the interest to combine the two spectroscopies was demonstrated since a better discrimination of the four stages was obtained using canonical correlation analysis. The examination of the spectral patterns associated with the principal components and the canonical variates showed that the structure of triglycerides acyl chains in fat globules was modified during cheeses ripening. The shift of the methylene bands in the infrared region and the changes of the shape of vitamin A fluorescence spectra agree with partial crystallization of triglycerides from 21 to 81 days of storage.

An ASA III patient presenting with a voluminous hemodialysis fistula aneurysm at the elbow was scheduled for its resection. Axillary brachial plexus block was performed under ultrasound and neurostimulation guidance. Despite unexpected nerve positions in relation to pathological vascular anatomy, this combined approach resulted in an adequate block with a low volume of local anesthetic, without obvious vascular puncture or intraneural injection.

The autocatalytic processing of procathepsin L was investigated in vitro using purified recombinant proenzyme expressed in Pichia pastoris. Pure intermolecular processing was studied by incubating the mutant procathepsin L (C25S), which cannot autoactivate with a small amount of mature active cathepsin L. The results clearly establish that, contrary to recent reports, intermolecular processing of procathepsin L is possible. The main cleavage sites are located at or near the N terminus of the mature enzyme, in an accessible portion of the proregion, which contains sequences corresponding to the known substrate specificity of cathepsin L. Contrary to procathepsins B, K, and S, autocatalytic processing of procathepsin L can generate the natural mature form of the enzyme. A continuous assay using the substrate benzyloxycarbonyl-Phe-Arg 4-methylcoumarinyl-7-amide hydrochloride has also been used to obtain information on the nature of the steps involved in the autocatalytic processing of wild-type procathepsin L. Processing is initiated by decreasing the pH from 8.0 to 5.3. The influence of proenzyme concentration on the rate of processing indicates the existence of both unimolecular and bimolecular steps in the mechanism of processing. The nature of the unimolecular event that triggers processing remains elusive. Circular dichroism and fluorescence measurements indicate the absence of large scale conformational change in the structure of procathepsin L on reduction of pH. However, the bimolecular reaction can be attributed to intermolecular processing of the zymogen.

The critical concentrations for β -lactoglobulin gelation at pH 7 and 8 in 50% ethanol solutions (v/v) were established. Then, the gelation kinetics at 25°C were followed by dynamical rheological methods and Fourier transform infrared spectroscopy. The gelation process was faster at pH 7 compared to pH 8. After 3 min, the infrared spectra of BLG in 50% ethanol solution indicated that the percentage of α helix was higher at pH 8 than at pH 7. Alcohol-induced aggregation of BLG was characterised by the formation of intermolecular hydrogen bonded β -sheet structures for the two pH values. The final gel structures were also investigated by small-angle neutron scattering. The data obtained on the molecular, mesoscopic and macroscopic levels showed that the kinetics of gelation were pH dependent contrary to the spatial arrangements of the aggregates in the final structures.

Mitochondrial disorders are nowadays recognized as impinging on most areas of medicine. They include specific and widespread organ involvement, including both tissue degeneration and tumour formation. Despite the spectacular progresses made in the identification of their underlying molecular basis, effective therapy remains a distant goal. Our still rudimentary understanding of the pathophysiological mechanisms by which these diseases arise constitutes an obstacle to developing any rational treatments. In this context, the idea of using a heterologous gene, encoding a supplemental oxidase otherwise absent from mammals, potentially bypassing the defective portion of the respiratory chain, was proposed more than 10 years ago. The recent progress made in the expression of the alternative oxidase in a wide range of biological systems and disease conditions reveals great potential benefit, considering the broad impact of mitochondrial diseases. This review addresses the state of the art and the perspectives that can be now envisaged by using this strategy.

The aim of this study is to measure the (complex) shape of an object by using a priori information given by its CAD representation in a 3D-DIC framework. In order to follow a 3D object during its deformation and to determine 3D surface displacement fields, a first measurement of the object shape is necessary. The main goal of the present method is to obtain a CAD representation of this measurement by updating the CAD reference via a global approach to 3D-DIC. Although in the majority of the shape measurement methods a cloud of points is obtained and subsequently interpolated to create a continuous description of the surface, CAD-based stereoDIC is devised to directly measure a 3D shape described by NURBS. This approach allows a direct link to be established between the theoretical CAD model and its true geometry thereby yielding the metrology of the measured surface in the CAD language.

The tricarboxylic acid cycle enzyme fumarate hydratase (FH) has been identified as a tumor suppressor in a subset of human renal cell carcinomas. Human FH-deficient cancer cells display high fumarate concentration and ROS levels along with activation of HIF-1. The underlying mechanisms by which FH loss increases ROS and HIF-1 are not fully understood. Here, we report that glutamine-dependent oxidative citric acid cycle metabolism is required to generate fumarate and increase ROS and HIF-1 levels. Accumulated fumarate directly bonds the antioxidant glutathione in vitro and in vivo to produce the metabolite succinated glutathione (GSF). GSF acts as an alternative substrate to glutathione reductase to decrease NADPH levels and enhance mitochondrial ROS and HIF-1 activation. Increased ROS also correlates with hypermethylation of histones in these cells. Thus, fumarate serves as a proto-oncometabolite by binding to glutathione which results in the accumulation of ROS.

Cyanide-resistant non-phosphorylating respiration is known in mitochondria from plants, fungi, and microorganisms but is absent in mammals. It results from the activity of an alternative oxidase (AOX) that conveys electrons directly from the respiratory chain (RC) ubiquinol pool to oxygen. AOX thus provides a bypath that releases constraints on the cytochrome pathway and prevents the over-reduction of the ubiquinone pool, a major source of superoxide. RC dysfunctions and deleterious superoxide overproduction are recurrent themes in human pathologies, ranging from neurodegenerative diseases to cancer, and may be instrumental in ageing. Thus, preventing RC blockade and excess superoxide production by means of AOX should be of considerable interest. However, because of its energy-dissipating properties, AOX might produce deleterious effects of its own in mammals. Here we show that AOX can be safely expressed in the mouse (MitAOX), with major physiological parameters being unaffected. It neither disrupted the activity of other RC components nor decreased oxidative phosphorylation in isolated mitochondria. It conferred cyanide-resistance to mitochondrial substrate oxidation and decreased reactive oxygen species (ROS) production upon RC blockade. Accordingly, AOX expression was able to support cyanide-resistant respiration by intact organs and to afford prolonged protection against a lethal concentration of gaseous cyanide in whole animals. Taken together, these results indicate that AOX expression in the mouse is innocuous and permits to overcome a RC blockade, while reducing associated oxidative insult. Therefore, the MitAOX mice represent a valuable tool in order to investigate the ability of AOX to counteract the panoply of mitochondrial-inherited diseases originating from oxidative phosphorylation defects., Author Summary In mammalian mitochondria, the energy-producing machinery is powered by the electron transfer to molecular oxygen, a mechanism whose terminal step is mediated by the cyanide-sensitive cytochrome c oxidase (COX). In plants, fungi, microorganisms, and some lower animals (but not in mammals), in addition to the normal pathway, a cyanide-resistant alternative oxidase (AOX) exists. It maintains electron transfer to oxygen even when the normal pathway is blocked. This provides a bypath that releases constraints on the energy producing machinery and prevents the production of deleterious superoxide molecules. Thus, preventing the energy producing machinery blockade and excess superoxide production by means of AOX should be of considerable interest. However, because of its energy-dissipating properties, AOX might produce deleterious effects of its own in mammals. Here we show that the AOX can be safely expressed in a mammal with major physiological and molecular parameters being unaffected. We also show that the AOX is active in vivo where it counteracts the energy producing machinery blockade and reduces in vitro the associated oxidative insult. Up to now, efficient therapies against mitochondrial-associated diseases are lacking dramatically. Therefore, in view of our results, the MitAOX mice represent a precious tool to assess the AOX therapeutic capacity against the panoply of inherited mitochondrial diseases.

Since β-lactoglobulin is resistant to peptic hydrolysis in physiological conditions, the increase of its digestibility by this enzyme was sought by the destabilization of its folding using methods that do not influence the biological value of protein, such as high pressure, medium polarity changes (alcohol addition), and esterification (ethylation). For example, the rate of hydrolysis of β-lactoglobulin by pepsin (negligible at 0.1 MPa) increased considerably with pressure up to 300 MPa. The susceptibility of all potential β-lactoglobulin proteolytic sites to peptic cleavage remained constant over the pressure range that was studied. The addition of alcohols decreases the bulk dielectric constant of the medium and, according to CD measurements, increases significantly the proportion of helical structure in β-lactoglobulin while increasing susceptibility to peptic hydrolysis. In the presence of alcohols (ethanol, ethylene glycol), β-lactoglobulin hydrolysis by pepsin was initiated when its secondary structure began to change and diversified peptic peptide populations were obtained. The chemical modification of β-lactoglobulin by mild esterification yields a 40%-ethylated β-lactoglobulin derivative that is rapidly hydrolyzed by pepsin. As compared with peptic hydrolysis of β-lactoglobulin in aqueous ethanol, 22 new sites of pepsin cleavage were induced by esterification of the protein.

Hydrolysis of β-lactoglobulin with thermolysin and pepsin at pressures ranging between 0.1 and 350 MPa showed a significant increase of cleavage rates. Pressure-induced changes of susceptibility to hydrolysis of β-lactoglobulin proteolytic sites were also observed. The pressure, raised to 200 MPa, accelerates the hydrolysis of β-lactoglobulin by thermolysin and changes obtained peptide profiles. Initially, higher pressure makes the N-terminal, and to a smaller extent, C-terminal peptide fragments of β-lactoglobulin molecule, more susceptible to removal by thermolysin. This indicates combined influence of pressure-induced thermolysin activation and partial unfolding of β-lactoglobulin by compression at neutral pHs. The rates of hydrolysis of β-lactoglobulin by pepsin (negligible at 0.1 MPa) are increased considerably with pressure up to 300 MPa. The Susceptibility of β-lactoglobulin proteolytic sites to peptic cleavage remains constant over all the studied pressure range. The lack of significant qualitative changes in the peptic peptide profiles produced at different pressures and at clearly pressure-dependent rates points to negative reaction volume changes as the major factor in peptic hydrolysis of β-lactoglobulin under high pressure. Thus the β-lactoglobulin molecule resists pressure-induced unfolding in acid pHs and yields to it in neutral pHs. © 1995 John Wiley & Sons, Inc.

Limited proteolysis of β-lactoglobulin and β-casein by pepsin was performed in the presence of varying concentrations of ethanol. β-Lactoglobulin started to be cleaved by pepsin only in ethanol concentrations greater than 20%, when its secondary structure began to change. In 25% ethanol, the rate of hydrolysis of β-lactoglobulin was slow (40% remained intact after 40 h of hydrolysis) and many short and hydrophilic peptides were observed. The rate of hydrolysis of β-lactoglobulin reached its maximum in 30 and 35% ethanol (80% of β-lactoglobulin was hydrolysed after 10 h), and a mixed population of hydrophilic and hydrophobic peptides of different lengths was observed. Large hydrophobic peptides appeared first, then some shorter products. The rate of hydrolysis of β-lactoglobulin decreased at ethanol concentrations equal to or higher than 40%, when only a few long, hydrophobic peptides were produced. As seen by circular dichroism, the addition of ethanol to β-casein induced α-helix formation and reduced the rate of casein hydrolysis without changing the peptide profile. The only exception was the yield of a single peptide (Pro81 − Met93).

BACKGROUND Ultrasound-guided perineural peripheral nerve block using a hydrodissection technique may reduce the risk of accidental intravascular local anesthetic (LA) injection. In this prospective randomized double-blind study, we tested the hypothesis that median nerve block effectiveness is not reduced when circumferential perineural hydrodissection with dextrose 5% in water (D5W) precedes LA injection. METHODS Patients scheduled for hand surgery were randomized to receive an ultrasound-guided median nerve block at the elbow to achieve circumferential perineural spread with either 6 mL of D5W followed by 6 mL of LA (lidocaine 1.5% with epinephrine 1:200,000) (D5W-LA group) or with 6 mL of LA alone (LA group). The primary outcome was onset time of successful anesthesia defined by a complete abolition of light touch sensation for the index finger. RESULTS Data from 95 patients were analyzed: 43 in the D5W-LA group and 52 in the LA group. Noninferiority tests were significant (all P < 0.05) for a critical limit of 7 minutes between D5W-LA and LA groups for onset time of the primary criterion, light touch block at index finger (mean ± SD, respectively: 23.9 ± 7.4 and 22.0 ± 7.9 minutes; 95% confidence interval [CI], -5.9 to 2.1 minutes), and for cold block at index fingertip, sensory blocks at thenar eminence, and motor block. Success rate at 30 minutes (defined as complete abolition for cold and light touch at index finger) was noted in 100% and 98.1% (95% CI, -6% to 10%) and 95.2% and 96.2% (95% CI, -13% to 9%) of patients for the D5W-LA and the LA groups. CONCLUSION Performing an ultrasound-guided perineural circumferential hydrodissection with D5W into which LA is injected leaves nerve block outcome unchanged. The assumption that this procedure may reduce the risk of intravascular injection and systemic toxicity remains to be demonstrated.

International audience; The potential of fluorescence imaging to discriminate different bovine muscles in relation with animal age, muscle type, chemical and mechanical properties was examined. Twenty-four muscles of three types (Gluteus medius, Longissimus dorsi, and Semitendinosus) and two animal age groups (10-13-years old and 12-24-months old) were obtained from the carcasses of Limousin breed cows. One hundred and forty-four images were collected at three illuminating conditions (exc 320 nm, exc 380 nm, and white light) using a custom-designed imager. The image cubes were processed using "regionprops" algorithm developed earlier in order to extract image shape features (number of shapes, area, major-axis-length, eccentricity, and solidity). Extracted image shape features were processed using custom-designed programs. The results of the PLSDA performed on image shape features showed 100% good discrimination for the three types of muscles. Muscle samples were also subjected to chemical analysis (dry matter, fat, pyridinoline, total, insoluble and soluble collagen) and mechanical tests (shear stress and breaking energy). PLSR models indicated relations between extracted image shape features and mechanical properties. i.e., R(2) = 0.69 and RMSEV = 0.514 were observed for breaking energy for adult-animal muscles. Regarding chemical composition, image shape features allowed to predict total collagen of L. dorsi with R(2) = 0.61 and RMSEV = 0.756. This study has demonstrated a promising potential of the custom-designed fluorescence imager combined with multivariate statistical tools in the study of beef meat. (C) 2011 Elsevier Ltd. All rights reserved.

Little is known of the environmental factors that initiate and promote disease. The aryl hydrocarbon receptor (AHR) is a key regulator of xenobiotic metabolism and plays a major role in gene/environment interactions. The AHR has also been demonstrated to carry out critical functions in development and disease. A qualitative investigation into the contribution by the AHR when stimulated to different levels of activity was undertaken to determine whether AHR-regulated gene/environment interactions are an underlying cause of cardiovascular disease. We used two congenic mouse models differing at the Ahr gene, which encodes AHRs with a 10-fold difference in signaling potencies. Benzo[a]pyrene (BaP), a pervasive environmental toxicant, atherogen, and potent agonist for the AHR, was used as the environmental agent for AHR activation. We tested the hypothesis that activation of the AHR of different signaling potencies by BaP would have differential effects on the physiology and pathology of the mouse cardiovascular system. We found that differential AHR signaling from an exposure to BaP caused lethality in mice with the low-affinity AHR, altered the growth rates of the body and several organs, induced atherosclerosis to a greater extent in mice with the high-affinity AHR, and had a huge impact on gene expression of the aorta. Our studies also demonstrated an endogenous role for AHR signaling in regulating heart size. We report a gene/environment interaction linking differential AHR signaling in the mouse to altered aorta gene expression profiles, changes in body and organ growth rates, and atherosclerosis.

Bovine β-lactoglobulin variant B was hydrolysed with thermolysin at various concentrations of calcium ions ranging between 0 and 50 m m . The changes in calcium concentration did not influence the overall rates of β-lactoglobulin proteolysis. However, HPLC analyses of the hydrolysates, obtained at nine different calcium concentrations, indicated that the rates of production and/or lysis of 3 of 17 identified peptides were calcium concentration-dependent. Proteolysis at low calcium concentrations yielded peptides V41-E45 and V43-L57. The peptide V43-L57, containing a cluster of dicarboxylic amino acids, was resistant to further hydrolysis by thermolysin even after 10 h incubation. An increase in calcium concentration triggered gradual hydrolysis of this peptide. Its hydrolytic product (peptide V43-D53) was obtained only by proteolysis of β-lactoglobulin with thermolysin at high calcium concentration.

International audience; The interactions of fatty acids with porcine and bovine β-lactoglobulins were measured using tryptophan fluorescence enhancement. In the case of bovine β-lactoglobulin, the apparent binding constants for most of the saturated and unsaturated fatty acids were in the range of 10–7 M at neutralpH. Bovine β-lactoglobulin displays only one high affinity binding site for palmitate with an apparent dissociation constant of 1·10–7 M. The strength of the binding was decreasing in the following way: palmitate > stearate > myristate > arachidate > laurate. Caprylic and capric acids are not bound at all. The affinity of β-lactoglobulin for palmitate decreased as thepH of the incubation medium was lowered and BLG/palmitate complex was not observed atpH's lower than 4.5. Surprisingly, chemically modified bovine β-lactoglobulin and porcine β-lactoglobulin did not bind fatty acids in the applied conditions.

The secondary structure transformation of beta-lactoglobulin from a predominantly beta-structure into a predominantly alpha-helical one, under the influence of solvent polarity changes is reversible. Independent of the alcohol used--methanol, ethanol, or 2-propanol--the midpoints of the observed structural transformation occur around dielectric constant epsilon approximately 60. The structural change destroying the hydrophobic core formed by the beta-barrel structure leads, at room temperature, to the dissociation of the retinol/beta-lactoglobulin complex in the neighborhood of dielectric constant epsilon approximately 50. However, when the dielectric constant of the medium is raised back to epsilon approximately 70 by the decrease of the temperature, both the refolding of BLG into a beta-structure and the reassociation of the retinol/beta-lactoglobulin complex are observed. The esterification of beta-lactoglobulin carboxyl groups has two effects: on the one hand it accelerates the beta-strand alpha-helix transition induced by alcohols. On the other hand, the esterification of beta-lactoglobulin strengthens its interaction with retinol as it may be deduced from the smaller apparent dissociation constant of retinol/methylated beta-lactoglobulin complex. The binding of retinol to modified or unmodified beta-lactoglobulin has no influence (stabilizing or destabilizing) on the folding changes induced by alcohol.

Rare diseases cover a group of conditions characterized by a low prevalence, affecting less than 1 in 2,000 people; 5000 to 7000 rare diseases have been currently identified in Europe. Most diseases do not have any curative treatment. They represent thus an important public health concern. CEMARA is based on a n-tier architecture. Its main objective is to collect continuous and complete records of patients with rare diseases, and their follow-up through a web-based Information System, and to analyse the epidemiological patterns. In France, 41 out of 131 labelled Reference Centres (RC) are sharing CEMARA. Presently 56,593 cases have been registered by more than 850 health care professionals belonging to 171 clinical sites. The national demand of care was explored in relation with the offer of care in order to reach an improved match. Within 2 years, CEMARA stimulated sharing a common platform, a common ontology with Orphanet and initiating new cohorts of rare diseases for improving patient care and research.

BACKGROUND: Nerve stimulation is an effective technique for peripheral nerve blockade. However, the local anesthetic (LA) distribution pattern obtained with this blind approach is unknown and may explain its clinical effects. METHODS: One hundred patients received a median nerve block at the elbow using a nerve stimulator approach. After correct needle placement defined by a minimal stimulating current ≤0.5 mA (2 Hz, 0.1 millisecond), 6 mL lidocaine 1.5% with epinephrine 1:200,000 was injected. A linear 5- to 13-MHz probe (12L-RS) was used to assess a cross-section area of median nerve, which was calculated by 3 consecutive measurements before and after injection, and LA circumferential spread around the nerve during static and longitudinal examination. Intraneural injection defined as an increase in nerve area was detected using an iterative method for outlier detection. Results of sensory tests (cold and light touch) on 3 nerve territories and of motor blockade were compared with the imaging aspects. We performed clinical neurological examination at 3 days and 1 month after block. RESULTS: Nerve swelling, considered significant when an increase in cross-sectional area was ≥75%, was observed in 43 patients. Nerve swelling associated with a circumferential LA spread image, present in 37 patients, was associated with a sensory success rate of 86%. The success rate was 34% for 32 patients in whom none of these signs was visualized. A circumferential spread around a nonswollen nerve, present in 25 patients, was followed by a sensory success rate of 76% within the 30-minute evaluation period. No major early neurological complications were observed. CONCLUSIONS: Nerve stimulation does not prevent intraneural injection. In the absence of intraneural injection, the presence of circumferential LA spread image seemed predictive of successful sensory block in almost 75% of the cases within the 30-minute evaluation period.

Cytochrome c oxidase (COX) deficiency is associated with a wide spectrum of clinical conditions, ranging from early onset devastating encephalomyopathy and cardiomyopathy, to neurological diseases in adulthood and in the elderly. No method of compensating successfully for COX deficiency has been reported so far. In vitro, COX-deficient human cells require additional glucose, pyruvate and uridine for normal growth and are specifically sensitive to oxidative stress. Here, we have tested whether the expression of a mitochondrially targeted, cyanide-resistant, alternative oxidase (AOX) from Ciona intestinalis could alleviate the metabolic abnormalities of COX-deficient human cells either from a patient harbouring a COX15 pathological mutation or rendered deficient by silencing the COX10 gene using shRNA. We demonstrate that the expression of the AOX, well-tolerated by the cells, compensates for both the growth defect and the pronounced oxidant-sensitivity of COX-deficient human cells.

International audience; In this study, the potential of synchronous front-face fluorescence spectroscopy (SFS) coupled with chemometrics was investigated for the determination of heterocyclic aromatic amines (HAA) in cooked meat samples. Bovine meat samples (1-2 mm thick, 5 cm diameter) taken from Longissimus thoracis muscle were cooked at an average temperature of 237 A degrees C for 5, 7 and 10 min. Four HAA (4, 8-DiMeIQx, MeIQx, IQx and PhIP) were determined on the cooked meat samples using classical LC-APCI-MS/MS method. In parallel, SFS spectra were recorded using a spectrofluorimeter on the same cooked meat samples in an excitation wavelength range of 250-550 nm using offsets of 20, 30, 40, aEuro broken vertical bar, 160 nm between excitation and emission monochromators. The three-dimensional synchronous fluorescence data set was analyzed using PARAFAC (parallel factor) analysis and N-PLS (n-way partial least square) regression method. PARAFAC analysis allowed capturing the fluorescence changes occurring in meat during cooking: the best model was obtained with 2 components (core consistency of 100% and explained variance of 99.2%). Whereas the loading profile of component 1 showed a maximum excitation at about 495 nm and an optimal offset of 60 nm, the loading profile of component 2 was characterized by a maximum excitation at 367 nm and an optimal offset of 90 nm. The results obtained using N-PLS regression showed good correlation between the spectral and analytical data: average recovery of 104% for 4, 8-DiMelQx, 102% for both MelQx and IQx, and 103% for PhIP were obtained. In conclusion this study indicates that SFS along with chemometrics has the potential to be used as a rapid and non-destructive technique for the determination of HAA contents in meat.

The binding of benzo(a)pyrene, ellipticine, and cis-parinaric acid to native, esterified, and alkylated beta-lactoglobulin was followed by enhancement of the ligand fluorescence. Three studied ligands bind to native or modified beta-lactoglobulin in apparent molar ratios varying between 1/8 and 2/1, with apparent dissociation constants in the range of 10(-8) M for ligand/beta-lactoglobulin complexes. The studied, chemically modified beta-lactoglobulin derivatives display higher binding affinities for all studied ligands, cis-parinaric acid excluded. The reductive alkylation of epsilon-NH2 lysyl residues of beta-lactoglobulin increases the apparent molar ratios of benzo(a)pyrene and cis-parinaric acid, and decreases it for ellipticine. The esterified and native beta-lactoglobulin complexed to the investigated ligands display similar stoichiometries. Dynamic light scattering study of ligand-beta-lactoglobulin complexes in solution shows the formation of aggregates: the apparent hydrodynamic radius value of beta-lactoglobulin dimer (3.4 nm) reaches 49, 46, and 74 nm upon addition and binding of benzo(a)pyrene, ellipticine, and cis-parinaric acid, respectively.

Summary - Porcine whey proteins have been separated by reversed-phase HPLC and the different eluted fractions were analysed by SD5-PAGE. Two protein fractions lately eluted from HPLC, with an apparent molecular weight of approximately 18 800 had an amino acid composition corresponding to that of porcine ~-Iactoglobulin. These 2 fractions differed only in their AlaNal content and consequently may be genetic variants of porcine ~-Iactoglobulin. In order to obtain larger amounts of ~-Iactoglobulin, we attempted to adapt to porcine whey a previously published method used for bovine ~-Iactoglobulin and based on NaCI salting-out at low pH. Each step of purification was monitored by RP-HPLC. After precipitation (14% NaCI), solubilisation in 7% NaCI and dialysis against distilled water, ~-Iactoglobulin was obtained with a purity of 94%. Final separation of ~-Iactoglobulin variants can be rapidly achieved by RP-HPLC on a semi-preparative column. ~-Iactoglobulin 1sow milk 1purification

Minerals play an important role in the structure and stability of casein micelles: minerals and caseins in milk are in dynamic equilibrium. Front-face synchronous fluorescence and mid-infrared spectra in combination with multivariate statistical analysis have been used to investigate, at a molecular level, the effects of added minerals (calcium, phosphate, or citrate) on mineral equilibria and casein micelle structure. Synchronous fluorescence spectra were recorded in the 250–500 nm excitation wavelength range using an offset of 80 nm between the excitation and emission monochromators for skim-milk samples fortified with 0, 3, 6, and 9 mM of calcium, phosphate, or citrate at 30 °C and 4 °C. Regarding mid-infrared spectroscopy, the region located between 1700–1500 cm−1, corresponding to the amide I and II bands, and the 1500–900 cm−1 region, called the fingerprint region, were considered for the characterization of the fortified skim-milk samples at the two considered temperatures. Principal component analysis (PCA) was applied to the collections of fluorescence and infrared spectral data of the two systems to optimize their description. The results show that the phenomena induced by the addition of phosphate were different from the ones observed following the addition of calcium or citrate, a calcium-chelating agent. Finally, common components and specific weights analysis was applied to infrared spectra and fluorescence data collected on fortified skim-milk samples. This analysis enabled the relationship between the different data tables to be established.