Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 1.060
Filter
1.
J Chem Eng Data ; 69(6): 2236-2243, 2024 Jun 13.
Article in English | MEDLINE | ID: mdl-38895647

ABSTRACT

During Li-ion battery operation, (electro)chemical side reactions occur within the cell that can promote or degrade performance. These complex reactions produce byproducts in the solid, liquid, and gas phases. Studying byproducts in these three phases can help optimize battery lifetimes. To relate the measured gas-phase byproducts to species dissolved in the liquid-phase, equilibrium proprieties such as the Henry's law constants are required. The present work implements a pressure decay experiment to determine the thermodynamic equilibrium concentrations between the gas and liquid phases for ethylene (C2H4) and carbon dioxide (CO2), which are two gases commonly produced in Li-ion batteries, with an electrolyte of 1.2 M LiPF6 in 3:7 wt/wt ethylene carbonate/ethyl methyl carbonate and 3 wt % fluoroethylene carbonate (15:25:57:3 wt % total composition). The experimentally measured pressure decay curve is fit to an analytical dissolution model and extrapolated to predict the final pressure at equilibrium. The relationship between the partial pressures and concentration of dissolved gas in electrolyte at equilibrium is then used to determine Henry's law constants of 2.0 × 104 kPa for C2H4 and k CO2 = 1.1 × 104 kPa for CO2. These values are compared to Henry's law constants predicted from density functional theory and show good agreement within a factor of 3.

2.
Molecules ; 29(1)2023 Dec 27.
Article in English | MEDLINE | ID: mdl-38202743

ABSTRACT

Higher rates of peanut allergy have been observed in countries that commonly roast peanuts prior to consumption. Despite the importance of understanding the role of thermal processing in allergy and on peanut composition, studies toward generating signatures that identify molecular contents following processing are scant. Here, we identified spectral signatures to track changes and differences in the molecular composition of peanuts under raw, roasted, and high-pressure and high-temperature autoclaved conditions. We analyzed both the solid flesh of the seed and solutions derived from soaking peanuts using High-Resolution Magic Angle Spinning (HR-MAS) and solution 1H Nuclear Magnetic Resonance (NMR) spectroscopy, respectively. The NMR spectra of intact peanuts revealed triglycerides as the dominant species, assigned on the basis of multiplets at 4.1 and 4.3 ppm, and corresponding defatted flours revealed the presence of sugars. Sucrose assigned based on a doublet at 5.4 ppm (anomeric proton), and triglycerides were the most abundant small molecules observed, with little variation between conditions. Soaked peanut solutions were devoid of lipids, and their resulting spectra matched the profiles of defatted peanuts. Spectral signatures resulting from autoclaving differed strikingly between those from raw and roasted peanuts, with considerable line-broadening in regions corresponding to proteins and amino-acid side chains, from 0.5 to 2.0 ppm and 6.5 to 8.5 ppm. Taken together, by using complementary NMR methods to obtain a fingerprint of the molecular components in peanuts, we demonstrated that autoclaving led to a distinct composition, likely resulting from the hydrolytic cleavage of proteins, the most important molecule of the allergic reaction.


Subject(s)
Arachis , Hypersensitivity , Protons , Flour , Magnetic Resonance Spectroscopy , Triglycerides
3.
Osteoarthritis Cartilage ; 29(2): 280-289, 2021 02.
Article in English | MEDLINE | ID: mdl-33246160

ABSTRACT

OBJECTIVE: Osteoarthritis (OA) is a degenerative joint disease inducing the degradation of the articular cartilage. Syndecan-4 (Sdc4) is a heparan sulfate proteoglycan, expressed under inflammatory conditions and by chondrocytes during OA. Little is known about Sdc4 shedding and its regulation in OA. Therefore, we investigated the regulation of Sdc4 shedding and underlying shedding mechanisms under OA conditions. DESIGN: Articular cartilage, serum, synovial fluid and synovial membrane from OA patients with different radiological severity were analyzed. ELISA, RT-qPCR and IHC for Sdc4, MMP-2 and -9 were performed. MMP inhibitors and siRNA were evaluated for their effect on Sdc4 shedding by ELISA and on IL-1 signaling by western blot (pERK/ERK). RESULTS: Shed Sdc4 was increased in synovial fluid of OA patients, but not in the serum and is a good predictor (AUC = 0.72) for OA severity with a sensitivity of 67.5% and specificity 65.2%. MMP-9, but not MMP-2, was increased in cartilage and synovial membrane at mRNA levels and in the synovial fluid at protein levels. Shed Sdc4 correlated with the amount of MMP-9 in synovial fluid. Further, the inhibition and knock-down of MMP-9 decreased the amount of shed Sdc4 in vitro. Increased Sdc4 shedding resulted in less phosphorylation of ERK upon IL-1ß stimulation. CONCLUSION: Shed Sdc4 might be a good prognostic biomarker for OA mediated cartilage degradation. MMP-9 seems to be the relevant sheddase for Sdc4 under OA conditions, desensitizing chondrocytes towards IL-1 signaling.


Subject(s)
Cartilage, Articular/metabolism , Chondrocytes/metabolism , Matrix Metalloproteinase 2/genetics , Matrix Metalloproteinase 9/genetics , Osteoarthritis, Knee/genetics , Syndecan-4/genetics , Synovial Fluid/metabolism , Synovial Membrane/metabolism , Chondrocytes/drug effects , Enzyme-Linked Immunosorbent Assay , Gene Knockdown Techniques , Humans , Immunohistochemistry , Interleukin-1beta/pharmacology , Matrix Metalloproteinase 2/drug effects , Matrix Metalloproteinase 2/metabolism , Matrix Metalloproteinase 9/drug effects , Matrix Metalloproteinase 9/metabolism , Matrix Metalloproteinase Inhibitors/pharmacology , Osteoarthritis, Knee/metabolism , RNA, Messenger , Severity of Illness Index , Syndecan-4/metabolism
4.
Invest New Drugs ; 39(1): 240-250, 2021 02.
Article in English | MEDLINE | ID: mdl-32648119

ABSTRACT

To enhance the potency of EGFR inhibitors, we developed a novel strategy that seeks to conjugate EGFR to a bioactive moiety leading to a molecule termed "combi-molecule". In order to mimic the penetration of this type of molecules, based upon previously reported structure activity relationship studies, we designed a new molecule containing a quinazoline moiety tethered to a p-nitrobenzoxadiazole (NBD) moiety [molecular weight (MW) 700]. Despite its size, AL906 growth inhibitory activity was superior to that of the clinical drug gefitinib. Furthermore, AL906 retained significant EGFR inhibitory activity and good cellular penetration with abundant distribution in the perinuclear region of the cells. In an isogenic NIH3T3 transfected cell panel, it selectively inhibited the growth  of the NIH3T3-EGFR and HER2 transfectants. Confocal microscopy analysis revealed that it was capable of penetrating multilayer aggregates although to a lesser extent than FD105, a small inhibitor of EGFR inhibitor of the same class (MW 300). Its ability to inhibit EGFR auto-phosphorylation in monolayer culture was stronger than in the aggregates. The results suggest that our strategy did not negatively affect EGFR inhibitory potency, EGFR selectivity and growth inhibition. However, its molecular size may account for its decreased aggregate penetration when compared with a smaller EGFR inhibitor of the quinazoline class.


Subject(s)
Antineoplastic Agents/pharmacology , Epidermal Growth Factor/antagonists & inhibitors , Fluorescence , Animals , Gefitinib/pharmacology , Genes, erbB-2/drug effects , Mice , NIH 3T3 Cells
5.
J Appl Microbiol ; 131(3): 1498-1514, 2021 Sep.
Article in English | MEDLINE | ID: mdl-33565669

ABSTRACT

AIMS: Joint infections cause premature implant failure. The avoidance of bacterial colonization of implant materials by modification of the material surface is therefore the focus of current research. In this in vitro study the complex interaction of periodic structures on PET and titanium surfaces on the adhesion of Staphylococcus aureus is analysed. METHODS AND RESULTS: Using direct laser interference patterning as well as roll-to-roll hot embossing methods, structured periodic textures of different spatial distance were produced on surfaces and S. aureus were cultured for 24 h on these. The amount of adhering bacteria was quantified using fluorescence microscopy and the local adhesion behaviour was investigated using scanning electron microscopy. For PET structures, minimal bacterial adhesion was identified for an aspect ratio of about 0·02. On titanium structures, S. aureus adhesion was significantly decreased for profile heights of < 200 nm. Our results show a significantly decreased bacterial adhesion for structures with an aspect ratio range of 0·02 to 0·05. CONCLUSIONS: We show that structuring on surfaces can decrease the amount of S. aureus on titanium and PET as common implant materials. SIGNIFICANCE AND IMPACT OF THE STUDY: The study highlights the immense potential of applying specific structures to implant materials to prevent implant colonization with pathogen bacteria.


Subject(s)
Bacterial Adhesion , Polyethylene Terephthalates/chemistry , Staphylococcus aureus , Titanium/chemistry , Prostheses and Implants/microbiology , Staphylococcus aureus/physiology , Surface Properties
6.
Int J Mol Sci ; 22(17)2021 Sep 03.
Article in English | MEDLINE | ID: mdl-34502481

ABSTRACT

The median-effect principle proposed by Chou and Talalay is the most effective approach to parameterize interactions between several agents in combination. However, this method cannot be used to evaluate the effectiveness of equimolar drug combinations, which are comparative references for dual-targeting molecular design. Here, using data acquired through the development of "combi-molecules" blocking two kinases (e.g., EGFR-c-Src and EGFR-c-Met), we established potency indices for equimolar and dual-targeted inhibitors. If the fold difference (κ) between the IC50 of the two individual kinase inhibitors was >6, the IC50 of their equimolar combination resembled that of the more potent inhibitor. Hence, the "combi-targeting" of the two kinases was considered "imbalanced" and the combination ineffective. However, if κ ≤ 6, the IC50 of the combination fell below that of each individual drug and the combi-targeting was considered "balanced" and the combination effective. We also showed that combi-molecules should be compared with equimolar combinations only under balanced conditions and propose a new parameter Ω for validating their effectiveness. A multi-targeted drug is effective if Ω < 1, where Ω is defined as the IC50 of the drug divided by that of the corresponding equimolar combination. Our study provides a methodology to determine the in vitro potency of equimolar two-drug combinations as well as combi-/hybrid molecules inhibiting two different kinase targets.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/pharmacology , Drug Delivery Systems , Models, Biological , Neoplasms/drug therapy , Protein Kinase Inhibitors/pharmacology , A549 Cells , Animals , Cricetulus , Female , Humans , Male , Mice , NIH 3T3 Cells , Neoplasms/metabolism , PC-3 Cells
7.
Opt Lett ; 45(11): 3013-3016, 2020 Jun 01.
Article in English | MEDLINE | ID: mdl-32479446

ABSTRACT

We demonstrate an efficient approach for enhancing the spectral broadening of long laser pulses and for efficient frequency redshifting by exploiting the intrinsic temporal properties of molecular alignment inside a gas-filled hollow-core fiber (HCF). We find that laser-induced alignment with durations comparable to the characteristic rotational time scale TRotAlign enhances the efficiency of redshifted spectral broadening compared to noble gases. The applicability of this approach to Yb lasers with (few hundred femtoseconds) long pulse duration is illustrated, for which efficient broadening based on conventional Kerr nonlinearity is challenging to achieve. Furthermore, this approach proposes a practical solution for high energy broadband long-wavelength light sources, and it is attractive for many strong field applications.

8.
Rev Med Liege ; 75(11): 697-698, 2020 Nov.
Article in French | MEDLINE | ID: mdl-33155440

ABSTRACT

Coronary aneurysm has an incidence of 1,1 to 4,9 % in patients undergoing a coronary angiography. Many etiologies may be accused, atherosclerosis is associated in up to 50 % of cases. We report the case of a 76-year-old patient with a large coronary aneurysm.


L'anévrisme coronarien a une incidence de 1,1 à 4,9 % chez les patients bénéficiant d'une coronarographie. De nombreuses étiologies peuvent être incriminées, l'athérosclérose y est associée dans 50 % des cas. Nous rapportons ici le cas d'un patient de 76 ans présentant un volumineux anévrisme coronarien.


Subject(s)
Atherosclerosis , Coronary Aneurysm , Aged , Coronary Aneurysm/diagnostic imaging , Coronary Aneurysm/etiology , Coronary Angiography , Humans
9.
Eur J Clin Pharmacol ; 75(4): 519-528, 2019 Apr.
Article in English | MEDLINE | ID: mdl-30554270

ABSTRACT

PURPOSE: Lithium (Li), the first-line treatment of bipolar disorder, was first developed as an immediate-release form with a routine therapeutic drug monitoring 12 h after the last dose. In Europe, the most commonly prescribed form is a sustained release (srLi). Yet no pharmacokinetics (PK) study has been published of srLi, administered once a day, in adults. The present study describes srLi PK in the serum and erythrocytes of bipolar patients. METHODS: To assess srLi PK, we studied prospectively 17 French bipolar patients on a median dose of 1000 mg (600-1600) for at least 2 years. Serum (S), erythrocyte (E) concentrations, and urinary (U) amount were collected over 8 h after 15 days of morning intake using monitoring electronic medical system (MEMs). Population PK parameters were estimated using the SAEM algorithm (MONOLIX 4.3.3 software). RESULTS: Using a population approach, we built a PK population model of srLi including one S compartment (VS = 23.0 L, ClS = 1.21 L h-1), one E compartment (VE = 64.7 L, ClSE = 3.63 L h-1, ClES = 9.46 L h-1), and one U compartment (F = 0.62) and estimate the ratio of concentrations to Li in E over S at 0.38 with 27% between-subject variability. CONCLUSION: This is a PK model of srLi once a day in bipolar patients using a population approach simultaneously describing Li concentrations in serum, erythrocytes, and urine which provide an estimate of the ratio of concentration in erythrocyte over serum and its between-subject variability (BSV).


Subject(s)
Bipolar Disorder/blood , Bipolar Disorder/urine , Erythrocytes/metabolism , Lithium Carbonate/administration & dosage , Lithium Carbonate/pharmacokinetics , Models, Biological , Adult , Bipolar Disorder/drug therapy , Delayed-Action Preparations , Female , Humans , Lithium Carbonate/blood , Lithium Carbonate/urine , Male
10.
Osteoarthritis Cartilage ; 26(6): 818-823, 2018 06.
Article in English | MEDLINE | ID: mdl-29559252

ABSTRACT

OBJECTIVE: The canonical Wnt signaling pathway has been shown to be involved in regulating chondrocyte hypertrophic differentiation during Osteoarthritis (OA). The aim of this study was to test the therapeutic potential of two stapled peptide canonical Wnt inhibitors - SAH-Bcl9 and StAx-35R - in preventing Wnt induced cartilage changes in OA. METHODS: Primary neonatal murine chondrocytes and cartilage explants from OA patients undergoing total joint replacement for knee OA, were used for microscopy to determine matrix and cell penetrating capacity of fluorescein isothiocyanate FITC-tagged SAH-Bcl9 and StAx-35R peptides. T cell factor/lymphoid enhancer-binding factor (TCF/LEF) reporter assays were used to monitor the inhibition of Wnt3a induced ß-catenin signaling by each peptide. Changes in chondrocyte phenotypic marker gene expression were analyzed by qRT PCR. RESULTS: Both peptides localized intercellular in primary murine chondrocytes and cartilage explants. They inhibited Wnt3a induced TCF/LEF promoter activity in primary murine chondrocytes. Both inhibitors did not rescue Wnt3a altered expression of chondrocyte phenotypic genes (Sox9, Col2a1, Acan) and hypertrophy marker gene (Col10a1) at high doses (100 ng/ml). Upon application of 10 ng/ml Wnt3a, StAx-35R partially reversed the Wnt effect on Sox9 and Col2a1 gene expression. Both peptides, however, reversed the downregulation of SOX9 and aggrecan (ACAN), and decrease of COL10A1 gene expression in preserved human OA cartilage explants. CONCLUSION: These data indicate that blockade of canonical Wnt signaling might be a therapeutic strategy to treat early OA cases and protect further cartilage degradation by preventing chondrocyte hypertrophic differentiation.


Subject(s)
Cartilage, Articular/drug effects , Chondrocytes/drug effects , Osteoarthritis/drug therapy , Peptide Fragments/pharmacology , Peptide Fragments/therapeutic use , Peptidomimetics/antagonists & inhibitors , Wnt Signaling Pathway/drug effects , beta Catenin/drug effects , Animals , Animals, Newborn , Cell Differentiation , Chondrocytes/pathology , Hypertrophy , Mice
11.
Inorg Chem ; 57(18): 11616-11625, 2018 Sep 17.
Article in English | MEDLINE | ID: mdl-30160480

ABSTRACT

Two diimine-bridged Ru(II),Mn(I) complexes with a [(bpy)2Ru(BL)Mn(CO)3Br]2+ architecture, where bpy = 2,2'-bipyridine and BL = 2,3-bis(2-pyridyl)pyrazine (dpp; Ru(dpp)Mn) or 2,2'-bipyrimidine (bpm; Ru(bpm)Mn), were designed to both dissociate multiple equivalents of CO and produce 1O2 when irradiated with visible light. Analysis of the complexes by Fourier transform infrared (FTIR) spectroscopy and cyclic voltammetry suggest a stronger π-accepting ability for bpm compared to that of dpp. Both complexes absorb light throughout the UV and visible regions with lowest energy absorption bands comprising overlapping Ru(dπ)→BL(π*) and Mn(dπ)→BL(π*) singlet metal-to-ligand charge transfer (1MLCT) and Br(p)→dpp(π*) singlet halide-to-ligand charge transfer (1XLCT) transitions. This lowest energy band is centered at 510 nm (ε = 12 000 M-1cm-1) for Ru(dpp)Mn and 553 nm (ε = 3240 M-1cm-1) for Ru(bpm)Mn, and the absorption band extends to nearly 700 nm in each case. Irradiation with visible light (both 470 and 627 nm) releases all three CO ligands, as observed by a combination of UV-vis, FTIR, and gas chromatography. The exchange of the first CO ligand with a solvent molecule occurs more efficiently for Ru(dpp)Mn (Φ470 = 0.22 ± 0.03 in H2O; 0.37 ± 0.06 in CH3CN) than for Ru(bpm)Mn (Φ470 = 0.049 ± 0.008 in H2O and 0.16 ± 0.03 in CH3CN), and the CO dissociation efficiency is unaffected by irradiation wavelength. The differences between Ru(dpp)Mn and Ru(bpm)Mn are proposed to result from the variation in electron density distribution across each formally reduced BL in the Mn(dπ)→BL(π*) 1MLCT excited state based on the nature of BL. Exhaustive photolysis causes the decomplexation of oxidized Mn(II), and the resulting [(bpy)2Ru(BL)]2+ complexes produce 1O2 with quantum yields (ΦΔ) of 0.37 ± 0.03 and 0.16 ± 0.01 for Ru(dpp) and Ru(bpm), respectively, with 460 nm irradiation. This bimetallic architecture presents the opportunity to use visible light to codeliver both CO and 1O2, both of which have biological relevance in photoactivated therapeutics, with spatiotemporal control.


Subject(s)
Carbon Monoxide/chemistry , Light , Manganese/chemistry , Photosensitizing Agents/chemistry , Ruthenium/chemistry , Ligands , Magnetic Resonance Spectroscopy , Models, Molecular , Spectroscopy, Fourier Transform Infrared
12.
Inorg Chem ; 57(5): 2865-2875, 2018 Mar 05.
Article in English | MEDLINE | ID: mdl-29446925

ABSTRACT

The synthesis of two new heteroleptic Cu(I) photosensitizers (PS), [Cu(Xantphos)(NN)]PF6 (NN = biq = 2,2'-biquinoline, dmebiq = 2,2'-biquinoline-4,4'-dimethyl ester; Xantphos = 4,5-bis(diphenylphosphino)-9,9-dimethylxanthene), along with the associated structural, photophysical, and electrochemical properties, are described. The biquinoline diimine ligand extends the PS light absorbing properties into the visible with a maximum absorption at 455 and 505 nm for NN = biq and dmebiq, respectively, in CH2Cl2 solvent. Following photoexcitation, both Cu(I) PS are emissive at low energy, albeit displaying stark differences in their excited state lifetimes (τMLCT = 410 ± 5 (biq) and 44 ± 4 ns (dmebiq)). Cyclic voltammetry indicates a Cu-based HOMO and NN-based LUMO for both complexes, whereby the methyl ester substituents stabilize the LUMO within [Cu(Xantphos)(dmebiq)]+ by ∼0.37 V compared to the unsubstituted analogue. When combined with H2O, N,N-dimethylaniline (DMA) electron donor, and cis-[Rh(NN)2Cl2]PF6 (NN = Me2bpy = 4,4'-dimethyl-2,2'-bipyridine, bpy = 2,2'-bipyridine, dmebpy = 2,2'-bipyridine-4,4'-dimethyl ester) water reduction catalysts (WRC), photocatalytic H2 evolution is only observed using the [Cu(Xantphos)(biq)]+ PS. Furthermore, the choice of cis-[Rh(NN)2Cl2]+ WRC strongly affects the catalytic activity with turnover numbers (TONRh = mol H2 per mol Rh catalyst) of 25 ± 3, 22 ± 1, and 43 ± 3 for NN = Me2bpy, bpy, and dmebpy, respectively. This work illustrates how ligand modification to carefully tune the PS light absorbing, excited state, and redox-active properties, along with the WRC redox potentials, can have a profound impact on the photoinduced intermolecular electron transfer between components and the subsequent catalytic activity.

13.
J Evol Biol ; 30(12): 2132-2145, 2017 Dec.
Article in English | MEDLINE | ID: mdl-28902471

ABSTRACT

Patterns of phenotypic and genic frequencies across hybrid zones provide insight into the origin and evolution of reproductive isolation. The Reunion grey white-eye, Zosterops borbonicus, exhibits parapatrically distributed plumage colour forms across the lowlands of the small volcanic island of Reunion (Mascarene archipelago). These forms meet and hybridize in regions that are natural barriers to dispersal (rivers, lava fields). Here, we investigated the relationship among patterns of differentiation at neutral genetic (microsatellite) markers, phenotypic traits (morphology and plumage colour) and niche characteristics across three independent hybrid zones. Patterns of phenotypic divergence revealed that these hybrid zones are among the narrowest ever documented in birds. However, the levels of phenotypic divergence stand in stark contrast to the lack of clear population neutral genetic structure between forms. The position of the hybrid zones coincides with different natural physical barriers, yet is not associated with steep changes in vegetation and related climatic variables, and major habitat transitions are shifted from these locations by at least 18 km. This suggests that the hybrid zones are stabilized over natural dispersal barriers, independently of environmental boundaries, and are not associated with niche divergence. A striking feature of these hybrid zones is the very low levels of genetic differentiation in neutral markers between forms, suggesting that phenotypic divergence has a narrow genetic basis and may reflect recent divergence at a few linked genes under strong selection, with a possible role for assortative mating in keeping these forms apart.


Subject(s)
Passeriformes/genetics , Animals , Gene Frequency , Hybridization, Genetic , Islands , Microsatellite Repeats , Passeriformes/anatomy & histology , Phenotype , Reproductive Isolation
14.
Bioorg Med Chem Lett ; 27(3): 688-694, 2017 02 01.
Article in English | MEDLINE | ID: mdl-28003142

ABSTRACT

In order to enhance the cytotoxic potential of poly(ADP-ribose) polymerase (PARP) inhibitors in BRCA1 or 2 deficient tumours, we designed a series of molecules containing a 1,2,3-triazene moiety tethered to a PARP targeting scaffold. A cell-based selectivity assay involving a BRCA2-deficient Chinese hamster cell line and its corresponding BRCA2 wild type transfectant, was used to predict the PARP targeting potential of the latter agents. The results showed that adding a DNA damaging function to the PARP inhibitors decreased but did not abrogate the selective targeting of the BRCA2-deficient cells. The DNA damaging moiety augmented the potency in BRCA2 deficient cells by 2-20 fold. The most selective dual PARP-DNA targeting agent 14b was found to possess dual DNA and PARP targeting properties.


Subject(s)
DNA/metabolism , Drug Design , Poly(ADP-ribose) Polymerase Inhibitors/chemical synthesis , Poly(ADP-ribose) Polymerase Inhibitors/pharmacology , Poly(ADP-ribose) Polymerases/metabolism , Animals , BRCA2 Protein/deficiency , BRCA2 Protein/genetics , Binding Sites , CHO Cells , Cricetinae , Cricetulus , DNA/chemistry , DNA Damage/drug effects , Enzyme Activation/drug effects , Molecular Docking Simulation , Poly(ADP-ribose) Polymerase Inhibitors/chemistry , Poly(ADP-ribose) Polymerases/chemistry , Protein Structure, Tertiary
15.
Osteoarthritis Cartilage ; 24(12): 2092-2099, 2016 12.
Article in English | MEDLINE | ID: mdl-27390030

ABSTRACT

OBJECTIVES: Based on the concept of a systemic predisposition for articular cartilage calcification (CC), the aim of this study was to determine the prevalence and amount of bilateral CC of hip and knee joints in an unselected sample cohort by high-resolution digital contact radiography (DCR) and to analyze the association of CC with histological OA. METHODS: Both hip and knee joints of 87 donors (48 m and 39 f; mean age 62) were analyzed by DCR in this post-mortem study of an unselected cohort of donors. Histological OA (OARSI) of the main load bearing area of femoral heads and medial femoral condyles was determined. RESULTS: The prevalence of CC of the femoral head was 96.6%, of the knee 94.3%. Bilateral calcification was detected in 79.3% of hips and 86.2% of knees. Concomitant CC of all four joints was detected in 69.0% of donors. There was no difference between the amount of CC of hips and knees (P = 0.47). The amount of CC of any given hip or knee correlated with that of the contralateral hip (rs = 0.54, P < 0.001) or knee (rs = 0.50, P < 0.001). There was a correlation between the amount of CC and histological OA (hips rs = 0.48, P < 0.001, knees rs = 0.30, P = 0.004), but not between CC and age (hips rs = -0.09, P = 0.42; knees rs = 0.10, P = 0.34). CONCLUSIONS: These data support the concept that articular CC occurs as the result of a systemic disorder. CC appears to be an early element of hip and knee OA pathogenesis independent of age.


Subject(s)
Calcification, Physiologic , Cartilage, Articular , Female , Humans , Knee Joint , Male , Middle Aged , Osteoarthritis , Radiography
16.
J Evol Biol ; 29(4): 824-36, 2016 Apr.
Article in English | MEDLINE | ID: mdl-26779843

ABSTRACT

Adaptation to local environmental conditions and the range dynamics of populations can influence evolutionary divergence along environmental gradients. Thus, it is important to investigate patterns of both phenotypic and genetic variations among populations to reveal the respective roles of these two types of factors in driving population differentiation. Here, we test for evidence of phenotypic and genetic structure across populations of a passerine bird (Zosterops borbonicus) distributed along a steep elevational gradient on the island of Réunion. Using 11 microsatellite loci screened in 401 individuals from 18 localities distributed along the gradient, we found that genetic differentiation occurred at two spatial levels: (i) between two main population groups corresponding to highland and lowland areas, respectively, and (ii) within each of these two groups. In contrast, several morphological traits varied gradually along the gradient. Comparison of neutral genetic differentiation (FST ) and phenotypic differentiation (PST ) showed that PST largely exceeds FST at several morphological traits, which is consistent with a role for local adaptation in driving morphological divergence along the gradient. Overall, our results revealed an area of secondary contact midway up the gradient between two major, cryptic, population groups likely diverged in allopatry. Remarkably, local adaptation has shaped phenotypic differentiation irrespective of population history, resulting in different patterns of variation along the elevational gradient. Our findings underscore the importance of understanding both historical and selective factors when trying to explain variation along environmental gradients.


Subject(s)
Altitude , Genetic Variation , Passeriformes/physiology , Selection, Genetic , Adaptation, Physiological/genetics , Animals , Biological Evolution , Islands , Microsatellite Repeats/genetics , Passeriformes/genetics , Phenotype
17.
Nature ; 466(7306): 604-7, 2010 Jul 29.
Article in English | MEDLINE | ID: mdl-20671706

ABSTRACT

The study of chemical reactions on the molecular (femtosecond) timescale typically uses pump laser pulses to excite molecules and subsequent probe pulses to interrogate them. The ultrashort pump pulse can excite only a small fraction of molecules, and the probe wavelength must be carefully chosen to discriminate between excited and unexcited molecules. The past decade has seen the emergence of new methods that are also aimed at imaging chemical reactions as they occur, based on X-ray diffraction, electron diffraction or laser-induced recollision--with spectral selection not available for any of these new methods. Here we show that in the case of high-harmonic spectroscopy based on recollision, this apparent limitation becomes a major advantage owing to the coherent nature of the attosecond high-harmonic pulse generation. The coherence allows the unexcited molecules to act as local oscillators against which the dynamics are observed, so a transient grating technique can be used to reconstruct the amplitude and phase of emission from the excited molecules. We then extract structural information from the amplitude, which encodes the internuclear separation, by quantum interference at short times and by scattering of the recollision electron at longer times. The phase records the attosecond dynamics of the electrons, giving access to the evolving ionization potentials and the electronic structure of the transient molecule. In our experiment, we are able to document a temporal shift of the high-harmonic field of less than an attosecond (1 as = 10(-18) s) between the stretched and compressed geometry of weakly vibrationally excited Br(2) in the electronic ground state. The ability to probe structural and electronic features, combined with high time resolution, make high-harmonic spectroscopy ideally suited to measuring coupled electronic and nuclear dynamics occurring in photochemical reactions and to characterizing the electronic structure of transition states.

18.
Prog Urol ; 26(6): 339-45, 2016 May.
Article in French | MEDLINE | ID: mdl-27233891

ABSTRACT

INTRODUCTION: Incidence of urolithiasis is increasing in industrialized countries. Amendments can be explained among others by dietary changes. More and more young patients have urolithiasis. The objective of this study was to analyze and update the epidemiology of stones in south of France about age and gender. MATERIAL AND METHODS: A retrospective single-center study from 2009 to June 2015 included all urolithiasis analyzed by infrared spectroscopy. Groups were composed according to the mineral content (oxalocalcic with whewellite and weddelite, calcium phosphate stones, uric acid stones…). RESULTS: A total of 749 stones were analyzed. The sex ratio was 1.96 all aged confused. The most common stones were oxalocalcic (51.3 %), followed mixed stones (21.2 %) and calcium phosphate stones (11.9 %). The calcium oxalate stones are mainly composed of whewellite (42 %) and calcium phosphate stones of carbapatite (18.6 %). The stones of whewellite were more frequent in men (P=0.0009), as well as uric acid stones (P=0.01) and mixed stones in women (P=0.00003), as well as calcium phosphate (P=0.0005). CONCLUSIONS: Epidemiology of stones has changed with an increased incidence in women, and nephrolithiasis patients getting older. A change in the type of stones is observed with increasing the proportion of mixed stones especially among women. Nutritional and metabolic studies are needed to find the etiology of the change in the epidemiology of urolithiasis. LEVEL OF EVIDENCE: 4.


Subject(s)
Urolithiasis/epidemiology , Adolescent , Adult , Age Distribution , Aged , Aged, 80 and over , Calcium Oxalate , Calcium Phosphates , Child , Child, Preschool , Female , France/epidemiology , Humans , Infant , Infant, Newborn , Male , Middle Aged , Retrospective Studies , Sex Distribution , Uric Acid , Young Adult
19.
Org Biomol Chem ; 13(43): 10734-44, 2015 Nov 21.
Article in English | MEDLINE | ID: mdl-26356422

ABSTRACT

The synthesis of eleven 1-deoxynojirimycin (DNJ) derivatives presenting either a monofluoro, difluoro, thiolated or unsaturated N-alkyl chain of various length is described. Exploiting the unsaturated moiety on the nitrogen, fluorine has been introduced through a HF/SbF5 superacid catalysed hydrofluorination and thiol-ene click chemistry allowed introduction of sulfur. The synthetic derivatives have been tested for their ability to inhibit glycosidases and correct F508del-CFTR. Two of the unsaturated iminosugars exhibited potency similar to Miglustat as F508del-CFTR correctors. The thioalkyl iminosugars as well as the corresponding alkyl iminosugars demonstrated low micromolar α-glucosidases and trehalases inhibition. Introduction of fluorine abolished F508del-CFTR correction and trehalase inhibition.


Subject(s)
1-Deoxynojirimycin/analogs & derivatives , Cystic Fibrosis Transmembrane Conductance Regulator/genetics , Enzyme Inhibitors/chemistry , Glycoside Hydrolase Inhibitors/chemistry , Trehalase/antagonists & inhibitors , 1-Deoxynojirimycin/pharmacology , Animals , Cystic Fibrosis Transmembrane Conductance Regulator/metabolism , Enzyme Inhibitors/pharmacology , Glycoside Hydrolase Inhibitors/pharmacology , Halogenation , Humans , Insecta , Mutation , Sulfhydryl Compounds/chemistry , Sulfhydryl Compounds/pharmacology , Swine , Trehalase/metabolism , alpha-Glucosidases/metabolism
20.
BJOG ; 122(13): 1728-38, 2015 Dec.
Article in English | MEDLINE | ID: mdl-25395365

ABSTRACT

OBJECTIVE: To examine the effects of pre-pregnancy alcohol drinking on child neuropsychological functioning. DESIGN: Prospective follow-up study. SETTING AND POPULATION: 154 women and their children sampled from the Danish National Birth Cohort. METHODS: Participants were sampled based on maternal alcohol consumption before pregnancy. At 5 years of age, the children were tested with the Wechsler Preschool and Primary Scale of Intelligence-Revised, the Test of Everyday Attention for Children at Five (TEACh-5), and the Movement Assessment Battery for Children (MABC). The Behaviour Rating Inventory of Executive Function (BRIEF) was completed by the mothers and a preschool teacher. Parental education, maternal IQ, prenatal maternal smoking, child's age at testing, child's sex, and maternal alcohol intake during pregnancy were considered potential confounders. MAIN OUTCOME MEASURES: Performance on the Wechsler Preschool and Primary Scale of Intelligence-Revised, the TEACh-5, the MABC, and the BRIEF. RESULTS: Intake of 15-21 drinks/week on average prior to pregnancy was not associated with any of the outcomes, but intake of ≥22 drinks/week on average was associated with a significantly lower adjusted mean full scale IQ and lower adjusted means in overall attention and sustained attention score, but not in selective attention score or any of the BRIEF index scores or MABC scores. CONCLUSIONS: Intake of ≥22 drinks/week before pregnancy was associated with lower mean full scale IQ, overall attention and sustained attention. Assessment of pre-pregnancy drinking provides additional information regarding potential prenatal alcohol exposure and its implications for child neurodevelopment.


Subject(s)
Alcohol Drinking/epidemiology , Prenatal Exposure Delayed Effects/epidemiology , Adult , Attention , Child, Preschool , Denmark/epidemiology , Female , Follow-Up Studies , Humans , Intelligence , Male , Neuropsychological Tests , Pregnancy , Prospective Studies , Psychological Tests , Risk Factors , Young Adult
SELECTION OF CITATIONS
SEARCH DETAIL