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1.
Nat Mater ; 8(2): 120-5, 2009 Feb.
Article in English | MEDLINE | ID: mdl-19151701

ABSTRACT

Present Li-ion batteries for portable electronics are based on inorganic electrodes. For upcoming large-scale applications the notion of materials sustainability produced by materials made through eco-efficient processes, such as renewable organic electrodes, is crucial. We here report on two organic salts, Li(2)C(8)H(4)O(4) (Li terephthalate) and Li(2)C(6)H(4)O(4)(Li trans-trans-muconate), with carboxylate groups conjugated within the molecular core, which are respectively capable of reacting with two and one extra Li per formula unit at potentials of 0.8 and 1.4 V, giving reversible capacities of 300 and 150 mA h g(-1). The activity is maintained at 80 degrees C with polyethyleneoxide-based electrolytes. A noteworthy advantage of the Li(2)C(8)H(4)O(4) and Li(2)C(6)H(4)O(4) negative electrodes is their enhanced thermal stability over carbon electrodes in 1 M LiPF(6) ethylene carbonate-dimethyl carbonate electrolytes, which should result in safer Li-ion cells. Moreover, as bio-inspired materials, both compounds are the metabolites of aromatic hydrocarbon oxidation, and terephthalic acid is available in abundance from the recycling of polyethylene terephthalate.

2.
Eur Phys J E Soft Matter ; 16(4): 415-20, 2005 Apr.
Article in English | MEDLINE | ID: mdl-15754083

ABSTRACT

We report on experiments to measure the temporal and spatial evolution of packing arrangements of anisotropic and weakly confined granular material, using high-resolution gamma-ray adsorption. In these experiments, the particle configurations start from an initially disordered, low-packing-fraction state and under vertical solicitations evolve to a dense state. We find that the packing fraction evolution is slowed by the grain anisotropy but, as for spherically shaped grains, can be well fitted by a stretched exponential. For a given type of grains, the characteristic times of relaxation and of convection are found to be of the same order of magnitude. On the contrary, compaction mechanisms in the media strongly depend on the grain anisotropy.

3.
Anal Chem ; 75(2): 175-84, 2003 Jan 15.
Article in English | MEDLINE | ID: mdl-12553749

ABSTRACT

In the case of a soluble polymer supported synthesis, the tuning of the support solubility depending on the solvent offers new opportunities for combinatorial chemistry for two reasons. First, organic syntheses in solution are generally easily translated on a soluble polymer supported substrate. Second, complete automation of the three successive steps of combinatorial chemistry (synthesis, analytical control, biological test) is approached without releasing the synthesized compound from the support. We report in this paper the preliminary results toward automation of both soluble polymer supported syntheses and their subsequent monitoring by ESI mass spectrometry.


Subject(s)
Combinatorial Chemistry Techniques/methods , Organic Chemicals/chemical synthesis , Polyethylene Glycols/chemistry , Automation , Combinatorial Chemistry Techniques/instrumentation , Drug Evaluation, Preclinical , Spectrometry, Mass, Electrospray Ionization
4.
Fundam Clin Pharmacol ; 17(5): 633-41, 2003 Oct.
Article in English | MEDLINE | ID: mdl-14703725

ABSTRACT

Our objective was to study age-related changes in adrenergic contractility and gene expression profile in the rat urinary bladder. Young (3-month old), adult (10-month old) and senescent (30-month old) male WAG/Rij rats were used. Gene expression profile in the rat urinary bladder was defined using Atlas microarray technology. In vitro contractile responses induced by KCl, phenylephrine (PHE) and norepinephrine (NE) were compared in isolated urinary bladders dissected from young, adult and senescent rats. Among a total of 1176 genes present on the arrays, 15 genes showed an increase in expression and 10 genes a decrease with age. Four genes related to nerve growth factor were upregulated whereas NOS type III was downregulated in aging rats. Intrinsic contractility of isolated rat urinary bladders was not changed between adult and aging rats as judged by the response curves to KCl. In contrast, an age-related increase in the maximal contractile responses to NE, but not PHE, was noticed (13 +/- 1, 48 +/- 2% and 59 +/- 2% at 3, 10 and 30 months, respectively). The alpha1D-adrenoceptor antagonist BMY7378 antagonized NE-induced contractions with low potency in both groups suggesting the involvement of the alpha1A-adrenoceptor subtype. This was confirmed by microarray, which demonstrated mRNA expression for the alpha1A-adrenoceptor subtype only. These results suggest that aging of the urinary bladder is associated with an increase in the maximal contractile response to NE which could be due to NO shortage resulting from downregulation of urothelial NOS III.


Subject(s)
Adrenergic Fibers/metabolism , Aging/metabolism , Nitric Oxide Synthase/biosynthesis , RNA, Messenger/biosynthesis , Urinary Bladder/metabolism , Adrenergic Fibers/drug effects , Aging/drug effects , Aging/genetics , Animals , Dose-Response Relationship, Drug , Gene Expression Regulation, Enzymologic/drug effects , Gene Expression Regulation, Enzymologic/physiology , Male , Muscle Contraction/drug effects , Muscle Contraction/physiology , Nitric Oxide Synthase/genetics , Nitric Oxide Synthase Type III , Norepinephrine/pharmacology , RNA, Messenger/genetics , Rats , Rats, Inbred Strains , Urinary Bladder/drug effects
5.
Mech Ageing Dev ; 123(4): 427-39, 2002 Feb.
Article in English | MEDLINE | ID: mdl-11744052

ABSTRACT

The effects of food restriction on liver glucagon and vasopressin V1a receptors, on AGE accumulation and on gene expression were investigated in 10- and 30-month-old WAG/Rij female rats fed ad libitum or chronically food-restricted by 30%. The age-related increase in glucagon and vasopressin V1a receptor density, as well as the rise in glucagon-induced cAMP generation was prevented by the restriction. AGE accumulation, characteristic of the aging process, was normalized in food-restricted animals. Gene expression determined with rat Atlas cDNA Expression Arrays containing 1176 cDNA indicates that a few genes exhibited a greater than twofold change in mRNA ratios with age. Most down-regulated genes were related to oxidative metabolism of lipids, and most of the up-regulated genes were concerned with the cell cycle and transcription factors. Chronic food restriction partially prevents these changes in gene expression and induces up- and down-regulation of several mRNAs which are not modified with age in ad libitum fed rats.


Subject(s)
Aging/metabolism , Food Deprivation/physiology , Gene Expression , Glycation End Products, Advanced/metabolism , Liver/metabolism , Signal Transduction/physiology , Aging/physiology , Angiotensin II/genetics , Animals , Body Weight , Cells, Cultured , Cyclic AMP/metabolism , Female , Glucagon/genetics , Hepatocytes/cytology , Hepatocytes/metabolism , Liver/cytology , Organ Size , Rats , Rats, Wistar , Vasopressins/genetics
7.
Chirurgie ; 115(3): 210-9, 1989.
Article in French | MEDLINE | ID: mdl-2805930

ABSTRACT

60 reconstructive procedures after T.C.P.L. for cancer were carried out between 1983 and 1988. The colon was used in 4 cases, complete stomach in 35 cases and free jejunal graft in 21 cases. The procedure was carried out for upper oesophageal involvement in 39 cases or required oesophageal resection in 21 cases. Hospital mortality was 3% (2 deaths). Morbidity was higher in the colonic plasty group (50%) than in the gastric plasty (30%) or free jejunal graft group (14%). Hospitalisation time was short and satisfactory alimentation was achieved. According to the authors, these results confirm the superiority of digestive plasties over cutaneous, myocutaneous or fascio-cutaneous flaps. The prognosis of these lesions remains poor; the wider excision which is made possible by these reconstructive methods, combined with chemotherapy and radiotherapy should lead to improved survival in these patients.


Subject(s)
Esophagoplasty , Adult , Aged , Colon/transplantation , Esophageal Neoplasms/surgery , Esophagoplasty/adverse effects , Esophagoplasty/mortality , Female , Humans , Jejunum/transplantation , Laryngectomy , Male , Middle Aged , Pharyngectomy , Postoperative Period , Stomach/transplantation
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