bluuebunny/crossref_metadata_2025_split huggingface dataset:
Réalisation et modification des propriétés de sélectivité d’une membrane minérale d’ultrafiltration : étude de la rétention de solutions salines
Authors: Chevereau Élodie , Limousy Lionel , Dutournié Patrick , Bourseau Patrick 
Published: September 2012

De par leurs caractéristiques structurales bien connues, les zéolithes sont fréquemment utilisées pour leur capacité à catalyser, à échanger des ions ou à adsorber certaines molécules. Ces matériaux sont également utilisés comme phase active pour réaliser des membranes.
Dans ce travail, une membrane céramique d’ultrafiltration a été réalisée en imprégnant de la Mordenite (phase active) sur un support en alumine.
La structure et les caractéristiques morphologiques de cette membrane ont été étudiées (diffraction de rayons X, BET / BJH (Brunauer-Emmett-Teller et Brunauer-Joyner-Hallenda), microscopie électronique à balayage). Des mesures de potentiels zêta et d’écoulement ont été réalisées sur la phase active en présence de différentes solutions salines, afin de caractériser qualitativement et quantitativement les charges de surface de la phase active de la membrane.
La sélectivité de la membrane vis-à-vis de solutions salines pures a été étudiée sur un pilote d’ultrafiltration de laboratoire. Aucune rétention n’a été observée lors de la filtration d’une solution de chlorure de sodium. Compte tenu des propriétés électriques de la membrane (fortement chargée négativement), une expérience de filtration a été réalisée en présence d’un sel divalent (Na2CO3). Dans ces conditions, une rétention importante a été observée. Après rinçage à l’eau pure, un nouvel essai de filtration a été réalisé en présence de solution de sel monovalent (NaCl) et a conduit à un taux de rétention de l’ordre de 10 % . Ce phénomène semble être lié au traitement et à la présence d’ions carbonates. Après un lavage acide, la membrane finit par retrouver ses propriétés initiales.
Pour conclure, une membrane Mordenite d’ultrafiltration a été réalisée avec des propriétés de filtration qui peuvent être réversiblement modifiées par un simple traitement chimique.
Solid‐Phase Chemical Synthesis of 5′‐Triphosphate DNA, RNA, and Chemically Modified Oligonucleotides
Authors: Zlatev Ivan , Manoharan Muthiah , Vasseur Jean‐Jacques , Morvan François 
Published: September 2012

AbstractA chemical method for the solid‐phase synthesis of 5′‐triphosphate oligonucleotides is described. The full‐length oligonucleotides are first constructed using standard solid‐phase DNA/RNA synthesis, and then efficient implementation of a sequential 4‐steps synthetic procedure, executed either manually or in a fully automated fashion, affords the corresponding solid‐supported 5′‐triphosphate oligonucleotides. Using this synthetic procedure, the full‐length 5′‐hydroxyl oligonucleotides are initially transformed into the corresponding 5′‐H‐phosphonate mono esters, subsequently oxidized in the presence of imidazole to the activated 5′‐phosphorimidazolidates, and finally reacted with pyrophosphate on the solid support. The method uses safe, stable, and inexpensive reagents, and the process is scalable and readily applicable to automated synthesis compatible with the current commercially available DNA/RNA synthesizers. After cleavage from the solid support and deprotection, a range of DNA, RNA, and chemically modified 5′‐triphosphate oligonucleotides are obtained in a convenient and efficient manner and isolated in good yields after HPLC purification. Curr. Protoc. Nucleic Acid Chem. 50:1.28.1‐1.28.16. © 2012 by John Wiley & Sons, Inc.
Synthesis of Threose Nucleic Acid (TNA) Phosphoramidite Monomers and Oligonucleotide Polymers
Authors: Zhang Su , Chaput John C. 
Published: September 2012

AbstractThis unit describes the preparation of dimethoxytrityl (DMTr)−protected α‐L‐threofuranosyl nucleic acid (TNA) phosphoramidite monomers for A, C, G, T, and diaminopurine, as well as their incorporation into TNA oligonucleotides by solid‐phase synthesis. Starting from commercially available L‐ascorbic acid, the protected threofuranosyl sugar is obtained in four steps. Vorbrüggen‐Hilbert‐Johnson glycosylation affords the desired threofuranosyl nucleosides, which are converted to their corresponding DMTr‐protected phosphoramidite nucleosides in four additional steps. Phosphoramidite monomers are then used to construct TNA oligonucleotides by solid‐phase synthesis using a standard DNA synthesizer. Curr. Protoc. Nucleic Acid Chem. 50:4.51.1‐4.51.26. © 2012 by John Wiley & Sons, Inc.
Convenient and Efficient Approach to the Permanent or Reversible Conjugation of RNA and DNA Sequences with Functional Groups
Authors: Cieślak Jacek , Ausín Cristina , Grajkowski Andrzej , Beaucage Serge L. 
Published: September 2012

AbstractThe conversion of 3′,5′‐disilylated 2′‐O‐(methylthiomethyl)ribonucleosides to 2′‐O‐(phthalimidooxymethyl)ribonucleosides is achieved in yields of 66% to 94%. Desilylation and dephtalimidation of these ribonucleosides by treatment with NH4F in MeOH produce 2′‐O‐aminooxymethylated ribonucleosides, which are efficient in producing stable and yet reversible 2′‐conjugates upon reaction with 1‐pyrenecarboxaldehyde. Exposure of 2′‐pyrenylated ribonucleosides to 0.5 M tetra‐n‐butylammonium fluoride (TBAF) in THF or DMSO results in the cleavage of their iminoether functions to give the native ribonucleosides along with an innocuous nitrile side product. Conversely, the reaction of 2′‐O‐(aminooxymethyl)uridine with 5‐cholesten‐3‐one leads to a permanent uridine 2′‐conjugate, which is left unreacted when treated with TBAF. The versatility and uniqueness of 2′‐O‐(aminooxymethyl)ribonucleosides is demonstrated by the single or double incorporation of a reversible pyrenylated uridine 2′‐conjugate into an RNA sequence. Furthermore, the conjugation of 2′‐O‐(aminooxymethyl)ribonucleosides with various aldehydes, including those generated from their acetals, is also presented. The preparation of 5′‐O‐(aminooxymethyl)thymidine is also achieved, albeit in modest yields, from the conversion of 5′‐O‐methylthiomethyl‐3′‐O‐(levulinyl)thymidine to 5′‐O‐phthalimidooxymethyl‐3′‐O‐(levuliny)lthymidine followed by hydrazinolysis of both 5′‐phthalimido and 3′‐levulinyl groups. Pyrenylation of the 5′‐O‐(aminooxymethyl)deoxyribonucleoside also provides a reversible 5′‐conjugate that is sensitive to TBAF, thereby further demonstrating the usefulness of 5′‐O‐(aminooxymethyl)deoxyribonucleosides for permanent or reversible modification of DNA sequences. Curr. Protoc. Nucleic Acid Chem. 50:4.52.1‐4.52.36. © 2012 by John Wiley & Sons, Inc.
Diversity of Insulin Resistance in Monkeys with Normal Glucose Tolerance
Authors: Bodkin Noni L. , Ortmyer Heidi K. , Hansen Barbara C. 
Published: September 2012

AbstractInsulin resistance has been proposed as a critical factor in the development of Type II diabetes, hypertension, dyslipidemia, and coronary artery disease. However, even in normal healthy individuals, a wide range of in vivo insulin action has been found. In the present study we sought to examine this heterogeneity in Insulin action in both normal and spontaneously obese nonhuman primates.Maximal insulin responsiveness as measured by a hyperinsulinemic euglycemic clamp, fasting plasma glucose, and insulin levels, β‐cell insulin response to glucose, glucose tolerance, and adiposity were measured in 22 male rhesus monkeys. Results showed that lean animals (body fat ≤ 22%) had higher insulin‐stimulated glucose uptake (M rate: 14.42±1.8 mg/kg FFM/min) compared to obese (8.08±0.8). The obese monkeys, with 23–49% body fat, had a wide range of M values (5.32‐14.29 mg/kg FFM/min) which showed no relationship to degree of adiposity. In all monkeys, M values had a strong inverse correlation with fasting plasma insulin levels (r=‐0.76; p<0.001), but not with fasting glucose or glucose disappearance rate.We conclude that neither degree of obesity above a critical threshold nor range of glucose tolerance is related to insulin resistance; however, in individuals with normal glucose tolerance an early reliable indicator of defective insulin action appears to be fasting insulin concentration. Longitudinal determination of basal insulin levels obtained under standardized conditions so as to minimize extraneous variability is likely to strengthen the ability to predict insulin resistance and possible later development of overt Type II diabetes.
Familial Aggregation of Morbid Obesity
Authors: Adams Ted D. , Hunt Steven C. , Mason Lesley A. , Ramirez Maria E. , Fisher A. Garth , Williams Roger R. 
Published: September 2012

AbstractRecent studies have shown major gene effects for obesity in randomly ascertained families. To investigate the familial aggregation of a specific subset of obesity, which is particularly prone to medical complications, families with morbid obesity were studied. This condition occurs in 1%‐2%of the population and is defined as 45.5 kg (100 pounds) or more over ideal weight. First‐degree relatives of 221 morbidly obese probands (1560 adults) were identified, and height and weight (current and greatest) were obtained from each family member. Morbid obesity occurred in the family members of the probands 8 times more often than in the general population. Of the morbidly obese probands, 48% had one or more first‐degree relatives who were also morbidly obese compared to a 6% population estimate. By the ages of 20–24, 12% of the morbidly obese probands were already 45.5 kg or more overweight, and 45% were 22.7 kg (50 pounds) or more overweight. There was little difference in the prevalence of familial morbid obesity by the gender of the probands: 47% of the male probands and 48% of the female probands had another morbidly obese relative, while 67% and 53% of the early onset (before age 25) male and female probands, respectively, had one or more first‐degree relatives who were also morbidly obese. In addition to the extreme degree of familial aggregation, the prevalence of morbid obesity in parent‐offspring sets was calculated within the morbidly obese families. Morbidly obese families who have one or two morbidly obese parents have a 2.6 times increased risk (p<0.002) of having one or more morbidly obese adult offspring, compared to families who have neither parent morbidly obese. Evidence for trimodality of the body mass index distribution was found for each gender (p = 0.0006 for male relatives and p = 0.075 for female relatives). The strong familial aggregation of morbid obesity indicates the need for further understanding of the genetic determinants of this extreme clinical disorder and how environmental factors affect the genetic expression of the trait. (OBESITY RESEARCH 1993;1:261–270)
BSB: A New Mouse Model of Multigenic Obesity
Authors: Fisler Janis S. , Warden Craig H. , Pace Mario J. , Lusis Aldons J. 
Published: September 2012

AbstractWe report here a new mouse model of multigenic obesity. Backcross progeny ((C57BL/6J xMus spretus)F1 x C57BL/6J), designated as BSB mice, range from 1% to 50% body fat. Since both parental strains are relatively lean, the wide range of the phenotype in the BSB mice indicates the involvement of multiple genes to produce obesity. Obesity in BSB mice results from increases in both intraabdominal and subcutaneous fat and is associated with hyperinsulinemia, hyperglycemia, and hyperlipidemia. Female and male BSB mice do not differ in the degree of obesity obtained. Stimulated plasma corticosterone levels are reduced in obese male and female mice. The development of appropriate genetic markers and statistical methods have made it feasible to analyze quantitative polygenic traits in animal models by employing F2 or backcross progeny. Thus, this BSB model is uniquely suited to the genetic analysis of the multifactorial quantitative trait of obesity and its associated phenotypes. (OBESITY RESEARCH 1993;1:271–280)
Sympathetic Activity, Age, Sucrose Preference, and Diet‐Induced Obesity
Authors: Levin Barry E. 
Published: September 2012

AbstractOnly half the adult male Sprague‐Dawley rats which are placed on a diet relatively high in calories, fat, and sucrose (HE diet) develop diet‐induced obesity (DIO). The rest are diet‐resistant (DR). Some chowfed rats prone to develop DIO on an HE diet have greater initial food intake of this diet and all have greater glucose‐induced plasma norepinephrine (NE) increases than DR‐prone rats. Here we looked for a relationship of sucrose preference or 24‐hour urinary catecholamine excretion as possible phenotypic markers of the DIO‐ and DR‐prone states before HE diet exposure as a function of age. When begun on an HE diet at 3 months of age, DIO‐prone rats gained 30% more weight over 3 months than DR‐prone rats and had 35% heavier retroperitoneal fat pads. While still on chow, sucrose preferences were similar, but 24 hour urine NE levels were 29% higher in DIO‐than in DR‐prone rats. The slope of the curve of urine NE versus body weight gain after 3 months on HE diet was 4‐fold greater in DIO‐ thaain DR‐prone rats. After 3 months on the HE diet, there was no statistical relationship between 24‐hour urine NE and body weight or prior body weight gain in DIO or DR rats. Six‐month‐old DIO‐prone rats had 126% and 128% more urine NE and gained 112% and 232% more weight after 3 months on HE diet than DR‐prone and chowfed rats, respectively. Only DIO‐prone rats showed a correlation (r=0.879; p=O.OS) between urine NE levels and subsequent weight gain on HE diet. Thus, 3‐ or 6‐ month‐old DIO‐ and DR‐prone rats can be identified by their 24‐hour basal urine NE levels but not sucrose preference prior to HE diet exposure. While this may suggest higher basal sympathetic activity in DIO‐prone rats, other explanations are possible. (OBESITY RESEARCH 1993;1:281–287)
Characteristics of the Obesity Syndrome in Zucker‐Brown Norway (ZBN) Hybrid Rats
Authors: Busch Bonnie L. , Johnson Patricia R. , Stern Judith S. , Greenwood M.R.C. , Horwitz Barbara A. 
Published: September 2012

AbstractThe existence of a restriction fragment length polymorphism (RFLP) closely linked to the fatty locus between the Zucker (Z) and Brown Norway (BN) rat strains allows evaluation of early effects of the fatty (fa) gene using offspring of back‐crosses (N2) between F1 females and Zucker obese males. We examined several metabolic characteristics of N2 animals to determine if these hybrid animals exhibited similar characteristics of the obese syndrome to those of Zucker rats. Females from crosses of obese male Zucker (fd/fa) and lean female BN (+/+) rats were back‐crossed to their sires, resulting in twelve N2 litters. At 9 weeks of age, liver, spleen, interscapular brown fat (IBAT), and gonadal, retroperitoneal (RP), and inguinal fat depots were removed and weighed. Samples of the RP depot were analyzed for cell size and number. Obese N2 rats were hyperphagic, with body weights in the range of those of obese Zucker rats. Obese N2 rats were also hyperinsulinemic [mean f SEM, pU/ml: females, 7.9 ± 0.6 vs. 82.1 f 8.4 (lean vs. obese); males, 10.5 ± 1.6 vs. 128.5 ± 13.4 (lean vs. obese)] and mildly hyperglycemic [mean ± SEM, mg/dl: females, 104.1 ± 2.0 vs. 139.0 ± 14.7 (lean vs. obese); males, 100.9 ± 2.6 vs. 132.0 ± 2.8 (lean vs. obese) p ≤ 0.05]. White fat depots in obese tats were 3 to 7 times heavier than those in lean rats; adipocyte numbers in RP depots were 50% greater in obese than in lean rats; and cell size was more than 3 times larger. IBAT, liver, and spleen were also heavier in obese vs. lean rats, while tail lengths were shorter. Percent lean carcass mass and % carcass protein were about 30% greater in lean vs. obese rats, while % carcass fat in obese rats was 5 times greater than that of lean rats. Thus, phenotypic expression of the fa gene in ZBN hybrid animals, with approximately 25% of their genetic background coming from the BN strain, appears to be similar to that in Zucker rats. Given the similarity of phenotypic expression of the fa gene between the Zucker strain and ZBN hybrids, it is plausible to consider using ZBN hybrids for studies of early manifestations of fa gene action prior to onset of detectable obesity.
A Randomized Double‐Blind Crossover Study of the Antiobesity Effects of Etiocholanedione
Authors: Zumoff Bamett , Strain Gladys W , Heymsfield Steven B. , Lichtman Steven 
Published: September 2012

AbstractEtiocholanedione (ED), a natural metabolite of dehy‐droepiandrosterone, has antiobesity effects in animals when given orally and is nontoxic. We carried out a trial of oral ED in obese humans. In a 20‐week randomized double‐blind crossover study, 14 subjects lost significantly more weight and body fat during treatment with oral ED, 4 gm daily, than during placebo administration. Mean weight loss during ED administration was 2.8 ± 5.5 kilograms, which was equivalent to 0.53 k 0.91 kilograms per week per 100 kilograms of body fat; mean weight change during placebo administration was essentially zero: M.21 ± 4.2 kg, or 4.04 ± 0.74 kg/wk/100 kg body fat. The difference between the weight changes in the two periods was significant: for A kg, P<0.05; for Δ kg/wk/100 kg body fat, P<0.03. Densitometric measurement of body fat content showed that the mean weight loss coincided almost exactly with the mean decrease in fat content; thus, over the 10‐week period of ED administration, the mean fat loss was about 5% of the initial body fat content. Three of the obese subjects had strikingly greater fat loss, about 18%, 19%, and 25% of the initial body fat content. There were no significant subjective or objective side effects of ED administration.
Determinants of Free‐Living Energy Expenditure in Normal Weight and Obese Women Measured by Doubly Labeled Water
Authors: Hibbert Jacqueline M. , Broemeling Lyle D. , Isenberg J. Nevin , Wove Robert R. 
Published: September 2012

AbstractTotal free‐living energy expenditure (TEE) was measured in 9 normal weight controls and 5 obese women using the doubly labeled water (DLW) method. Resting energy expenditure (REE) and the thermic effect of food (TEF) were measured by indirect calorimetry and the energy cost of physical activity (PA) calculated by deduction, in order to quantify the components and identify determinants of free‐living TEE. Although REE was quantitatively the major component of TEE in both groups, PA best explained the variability, contributing 76% to the variance in free‐living TEE. The obese women had elevated values for TEE (12397+/‐2565 vs. 8339+/‐1787 kJ/d, mean+/‐SD; p<0.00S), compared with the control women. PA (5071+/‐2385 vs. 2552+/‐1452; p<0.0S) and REE (6393+/‐678 vs. 5084+/‐259; p<0.000S) were also raised in the obese, whereas TEF was not significantly different between the groups, accounting for 7.6% of energy expenditure for the obese and 8% for the control subjects. Body weight was the single best determinant of mean daily free‐living TEE across both groups. We conclude that PA and body weight are the main determinants of free‐living TEE.
Factors Associated with Weight Control in Older Adults
Authors: Rosendahl Eileen H. , Kirschenbaum Daniel S. 
Published: September 2012

AbstractDieting behaviors in a sample of 183 overweight older adults were studied to assess how they were influenced by six cognitive, behavioral, emotional, and social variables. Membership in a weight control program was also evaluated to assess whether it affected these relationships. Responses indicated that reports of high quality dieting behaviors were associated with higher levels of depression and less effective coping skills. Dieting behaviors among subjects who were participants in weight loss programs were not as strongly associated with less effective coping skills, but were associated with external health locus‐of‐control. The degree of social support had a limited impact on dieting behaviors, while measures of optimism and health status were unrelated to dieting behaviors. We concluded that older adults, especially those who diet independently, are likely to experience significant stress associated with weight loss efforts. Weight loss programs for older adults might produce better outcomes if they focus on reducing depression and stress associated with dieting.
Effects of a Fat Substitute, Sucrose Polyester, on Food Intake, Body Composition, and Serum Factors in Lean and Obese Zucker Rats
Authors: Grossman Barbara Mullen , Akoh Casimir C. , Hobbs Jerri K. , Martin Roy J. 
Published: September 2012

AbstractSucrose polyester, a fat substitute, has shown promise in reducing blood cholesterol and body weight of obese individuals. Effects of this compound in the Zucker rat, a genetic model of obesity, are unknown. Thus, we examined food intake, body weight, body composition, and several metabolic parameters in sera of lean and obese female Zucker rats. Eight‐week‐old lean and obese animals were given a choice between a control diet (15% corn oil) and fat substitute diet (5% corn oil and 10% sucrose polyester) for 2 days. Next, one‐half of the lean and obese groups received control diet; the remaining lean and obese rats received fat substitute diet for 18 days. Cumulative food intake was depressed in fat substitute groups relative to control‐fed animals; however, this effect was more predominant in obese animals. Obese rats consuming fat substitute diet (O‐FS) gained less weight as compared to obese control‐fed animals (O‐C). Lean rats given fat substitute (L‐FS) did not have significantly different body weights as compared to the L‐C group. Fat substitute groups, combined, had lower body fat and higher body water as compared to controls. The O‐FS group had lower serum glucose and insulin and higher fatty acid levels compared to the O‐C group. There were no differences in serum cholesterol, HDL, or triglyceride levels due to fat substitute diet. These data suggest that the obese Zucker rat is unable to defend its body weight when dietary fat is replaced with sucrose polyester.