bluuebunny/crossref_metadata_2025_split huggingface dataset:
Global and Regional Effects of Type 2 Diabetes on Brain Tissue Volumes and Cerebral Vasoreactivity
Authors: Last David , Alsop David C. , Abduljalil Amir M. , Marquis Robert P. , de Bazelaire Cedric , Hu Kun , Cavallerano Jerry , Novak Vera 
Published: April 2007

OBJECTIVE—The aim of this study was to evaluate the regional effects of type 2 diabetes and associated conditions on cerebral tissue volumes and cerebral blood flow (CBF) regulation.
RESEARCH DESIGN AND METHODS—CBF was examined in 26 diabetic (aged 61.6 ± 6.6 years) and 25 control (aged 60.4 ± 8.6 years) subjects using continuous arterial spin labeling (CASL) imaging during baseline, hyperventilation, and CO2 rebreathing. Regional gray and white matter, cerebrospinal fluid (CSF), and white matter hyperintensity (WMH) volumes were measured on a T1-weighted inversion recovery fast-gradient echo and a fluid attenuation inversion recovery magnetic resonance imaging at 3 Tesla.
RESULTS—The diabetic group had smaller global white (P = 0.006) and gray (P = 0.001) matter and larger CSF (36.3%, P &lt; 0.0001) volumes than the control group. Regional differences were observed for white matter (−13.1%, P = 0.0008) and CSF (36.3%, P &lt; 0.0001) in the frontal region, for CSF (20.9%, P = 0.0002) in the temporal region, and for gray matter (−3.0%, P = 0.04) and CSF (17.6%, P = 0.01) in the parieto-occipital region. Baseline regional CBF (P = 0.006) and CO2 reactivity (P = 0.005) were reduced in the diabetic group. Hypoperfusion in the frontal region was associated with gray matter atrophy (P &lt; 0.0001). Higher A1C was associated with lower CBF (P &lt; 0.0001) and greater CSF (P = 0.002) within the temporal region.
CONCLUSIONS—Type 2 diabetes is associated with cortical and subcortical atrophy involving several brain regions and with diminished regional cerebral perfusion and vasoreactivity. Uncontrolled diabetes may further contribute to hypoperfusion and atrophy. Diabetic metabolic disturbance and blood flow dysregulation that affects preferentially frontal and temporal regions may have implications for cognition and balance in elderly subjects with diabetes.
Sleep Duration and Snoring in Relation to Biomarkers of Cardiovascular Disease Risk Among Women With Type 2 Diabetes
Authors: Williams Catherine J. , Hu Frank B. , Patel Sanjay R. , Mantzoros Christos S. 
Published: April 2007

OBJECTIVE—Sleep habits have been associated with risk of cardiovascular disease (CVD) and metabolic disturbances, but the mechanisms underlying these associations have yet to be fully elucidated. We aim to determine whether sleep duration and/or snoring are associated with biomarkers of CVD in women with type 2 diabetes.
RESEARCH DESIGN AND METHODS—We studied 935 women aged 43–69 years enrolled in the Nurses’ Health Study cohort with type 2 diabetes who had no history of documented coronary heart disease or stroke in 1990. Information on sleep duration and snoring frequency was collected in 1986 from mailed questionnaires, and biomarkers of CVD were measured from blood samples taken in 1989–1990.
RESULTS—Longer sleep duration was associated with increased levels of C-reactive protein after adjusting for age, BMI, lifestyle factors, family history of diabetes, glycemic control, and medication use (P = 0.05). HDL was decreased with short and long sleep duration among normotensive (P = 0.02) but not hypertensive women. More frequent snoring was directly associated with triglycerides (P = 0.02) and inversely associated with HDL cholesterol (0.03) and adiponectin (P = 0.03) in multivariate-adjusted analyses.
CONCLUSIONS—The associations of sleep duration and snoring with lipid profile, hormone measures, and/or inflammatory markers may partially explain the previously reported relationship between sleep habits and cardiovascular and metabolic disorders.
Endothelial Function Varies According to Insulin Resistance Disease Type
Authors: Beckman Joshua A. , Goldfine Allison B. , Dunaif Andrea , Gerhard-Herman Marie , Creager Mark A. 
Published: April 2007

OBJECTIVE—We examined the relationship between insulin resistance and vascular function in three insulin-resistant states (type 2 diabetes, non-HIV lipodystrophic diabetes, and nondiabetic polycystic ovary syndrome [PCOS]) and in healthy control subjects.
RESEARCH DESIGN AND METHODS—The population included 12 women with type 2 diabetes, 6 with lipodystrophic diabetes, 10 with PCOS, and 19 healthy female subjects. Metabolic measures included insulin sensitivity by the homeostasis model assessment, lipids, free fatty acids, and adiponectin. High-resolution B-mode ultrasound was used to determine endothelium-dependent and -independent vasodilation.
RESULTS—Type 2 diabetic, liposdystrophic, and PCOS subjects were insulin resistant compared with control subjects (P = 0.001). Flow-mediated vasodilation was reduced in diabetic (3.4 ± 1.3%) compared with control (7.3 ± 1.1%) subjects but not in lipodystrophic (7.7 ± 1.2%) or PCOS (9.9 ± 0.7%) subjects (P = 0.005). Nitroglycerin-mediated vasodilation was attenuated in both diabetic (15.2 ± 2.0%) and lipodystrophic (16.7 ± 3.6%) subjects compared with healthy control (24.6 ± 2.4%) and PCOS (23.2 ± 1.8%) subjects (P = 0.019). Insulin resistance, free fatty acids, adiponectin, or C-reactive protein did not associate with vascular dysfunction.
CONCLUSIONS—Among these different types of patients with insulin resistance, we found abnormal endothelium-dependent vasodilation only in the patients with type 2 diabetes. We postulate that variations in the mechanism of insulin resistance may affect endothelial function differently than glucose homeostasis.
Serum Alanine Aminotransferase Levels Decrease Further With Carbohydrate Than Fat Restriction in Insulin-Resistant Adults
Authors: Ryan Marno Celeste , Abbasi Fahim , Lamendola Cindy , Carter Susan , McLaughlin Tracey Lynn 
Published: April 2007

OBJECTIVE—Although weight loss interventions have been shown to reduce steatosis in nonalcoholic fatty liver disease (NAFLD), the impact of dietary macronutrient composition is unknown. We assessed the effect on serum alanine aminotransferase (ALT) concentrations of two hypocaloric diets varying in amounts of carbohydrate and fat in obese insulin-resistant individuals, a population at high risk for NAFLD.RESEARCH DESIGN AND METHODS—Post hoc analysis of ALT concentrations was performed in 52 obese subjects with normal baseline values and insulin resistance, as quantified by the steady-state plasma glucose (SSPG) test, who were randomized to hypocaloric diets containing either 60% carbohydrate/25% fat or 40% carbohydrate/45% fat (15% protein) for 16 weeks. The primary end point was change in ALT, which was evaluated according to diet, weight loss, SSPG, and daylong insulin concentrations.RESULTS—Although both diets resulted in significant decreases in weight and SSPG, daylong insulin, and serum ALT concentrations, the 40% carbohydrate diet resulted in greater decreases in SSPG (P &lt; 0.04), circulating insulin (P &lt; 0.01), and ALT (9.5 ± 9.4 vs. 4.2 ± 8.3 units/l; P &lt; 0.04) concentrations. ALT changes correlated with improvement in insulin sensitivity (P = 0.04) and daylong insulin (P &lt; 0.01). Individuals with ALT concentrations above the proposed upper limits experienced significant declines in ALT, unlike those with lower ALT levels.CONCLUSIONS—In a population at high risk for NAFLD, a hypocaloric diet moderately lower in carbohydrate decreased serum ALT concentrations to a greater degree than a higher-carbohydrate/low-fat diet, despite equal weight loss. This may result from a relatively greater decline in daylong insulin concentrations. Further research with histological end points is needed to further explore this finding.
Efficacy and Cost of Postpartum Screening Strategies for Diabetes Among Women With Histories of Gestational Diabetes Mellitus
Authors: Kim Catherine , Herman William H. , Vijan Sandeep 
Published: April 2007

OBJECTIVE—To compare the cost and time to diagnosis associated with several screening strategies for diabetes in women with histories of gestational diabetes mellitus (GDM).
RESEARCH DESIGN AND METHODS—We simulated screening for diabetes with fasting plasma glucose (FPG), a 2-h oral glucose tolerance test (OGTT), and A1C annually, every 2 years, and every 3 years over a period of 12 years. We assumed that women had negative screening tests 6 weeks after delivery, progressed to diabetes at 8% per year, and that each positive FPG and A1C was followed by a confirmatory FPG. For each strategy, we calculated the cost per case detected, cost per woman screened, the percent of cases detected, and the time elapsed with undiagnosed diabetes. In sensitivity analyses, we considered the inclusion of indirect costs, the impact of imperfect adherence to screening strategies, exclusion of confirmatory tests, and lower rates of progression to diabetes.
RESULTS—When annual, biannual, or every 3-year screening strategies were utilized, OGTTs resulted in lower costs per case detected than FPG or A1C. Testing every 3 years resulted in lower costs per case detected compared with more frequent testing. These patterns persisted in sensitivity analyses, except that FPG resulted in lower cost per case detected than OGTT, assuming annual screening and inclusion of indirect costs or assuming annual screening without a confirmatory FPG.
CONCLUSIONS—Screening every 3 years with OGTTs results in the lowest cost per case of detected diabetes.
Insulin Resistance in Liver Cirrhosis Is Not Associated With Circulating Retinol-Binding Protein 4
Authors: Yagmur Eray , Weiskirchen Ralf , Gressner Axel M. , Trautwein Christian , Tacke Frank 
Published: April 2007

OBJECTIVE—Retinol-binding protein 4 (RBP4) has been identified as a novel adipokine mediating systemic insulin resistance, and elevated serum RBP4 indicates overt or impending insulin resistance in lean, obese, and type 2 diabetic subjects. As insulin resistance is present in nearly all patients with liver cirrhosis, we evaluated RBP4 in patients with chronic liver disease (CLD).RESEARCH DESIGN AND METHODS—Serum RBP4 was measured in 111 CLD patients. Ninety-nine age- and sex-matched healthy blood donors served as control subjects. RBP4 gene expression was also quantified in normal and cirrhotic rat liver.RESULTS—In CLD patients, serum RBP4 was significantly reduced compared with healthy control subjects and closely correlated with the stage of liver cirrhosis. CLD patients without cirrhosis showed normal RBP4 concentrations, which correlated with serum glucose and insulin secretion and inversely correlated with insulin sensitivity. In patients with Child A-C liver cirrhosis, however, RBP4 was not correlated with glucose metabolism or other adipokines, such as adiponectin or resistin, but closely linked to the hepatic biosynthetic capacity, fibrotic changes in liver histology, or clinical complications such as portal hypertension. In an animal model of experimental cirrhosis, hepatic RBP4 gene expression decreased in cirrhotic liver.CONCLUSIONS—RBP4 appears, unlike in obesity or type 2 diabetes, not to be a relevant systemic factor in the pathogenesis of insulin resistance in liver cirrhosis. Liver function has a tremendous impact on RBP4 levels, and future studies will need to take liver function into account when examining serum RBP4 levels.
Evolutionary mechanisms of circadian clocks
Authors: Rodrigo Guillermo , Carrera Javier , Jaramillo Alfonso 
Published: April 2007

AbstractAn intriguing question in biology is to know how circadian molecular networks could have evolved their particular topologies to adjust to a daily period. We analyze the mechanism of the evolution of such networks by using a computational design strategy that allows for the generation of synthetic networks with a targeted 24 hours oscillation. We have performed a systematic analysis of all possible two-gene network topologies based on a core activator-repressor frequently found in circadian mechanisms. We have considered transcriptional and post-translational regulations to implement this core. We have applied our analysis to both, eukaryotic and prokaryotic circadian machinery. Finally, we conjecture a possible mechanism for the evolution of circadian clocks.
Molecular cloning and analysis of the human PCAN1 (GDEP) promoter
Authors: Liu Wenwen , Chen Weiwen , Zhang Pengju , Yu Chunxiao , Kong Feng , Deng Jingti , Zhang Jianye , Jiang Anli 
Published: April 2007

AbstractHuman PCAN1 (prostate cancer gene 1) is a prostate-specific gene that is highly expressed in prostate epithelial tissue, and frequently mutated in prostate tumors. To better understand the regulation of the PCAN1 gene, a 2.6-kb fragment of its 5′ flanking region was obtained by PCR. Its promoter activity was examined via the dual-luciferase reporter assay after it had been cloned into a pGL3-basic vector generating pGL3-p2.6kb and transfected into LNCaP cells. pGL3-basic and pGL3-control were respectively used as the negative and positive controls. Sequence analysis with the MatInspector database showed that some possible binding sites for the transcriptional factors, NKX3.1, P53, SP1, cEBP and the PPAR/RXR heterodimers may locate on a 2.6-kb region upstream of the PCAN1 gene. To examine the relevant regulation of PCAN1, pGL3-p2.6kb was transfected into the prostate cancer cell line LNCaP, which was treated with R1881 (10−7∼10−9 mol/l), 17β-estradiol (17β-E2, 10−7∼10−9 mol/l), all-trans-retinoic acid (all-trans-RA, 10−5∼10−7 mol/l) or 9-cis-retinoic acid (9-cis-RA, 10−5∼10−7 mol/l), and eukaryotic expression plasmids of NKX3.1, p53, Sp1, Pten, PPARγ or cEBPα were cotransfected with pGL3-p2.6kb into LNCaP cells. pRL-TK, a Renilla luciferase reporter vector, was cotransfected into all the transfection lines as an internal control. The activities of pGL3-p2.6kb (PCAN1 promoter) were analyzed via the dual-luciferase reporter assay 48 h after transfection. The results showed that 9-cis-RA enhanced the PCAN1 promoter activity in a dose-dependent manner, while R1881, 17β-E2 and all-trans-RA had no significant effect on PCAN1 promoter activities. Cotransfection with pGL3-p2.6kb and the expression plasmids of NKX3.1, p53, Sp1 or Pten respectively resulted in 1.66-, 2.48-, 2.00-and 1.72-fold 2.6 kb PCAN1 promoter activity increases relative to the controls, which were cotransfected with pcDNA3.1(+), while cotransfection of PPARγ and cEBPα yielded no significant effect on PCAN1 promoter activities. These results could be applied for further study of the function and transcription regulation of the PCAN1 gene in prostate development and carcinogenesis.
Gyrodactylus derjavinoides sp. nov. (Monogenea, Platyhelminthes) on Salmo trutta trutta L. and G. derjavini Mikailov, 1975 on S. t. caspius Kessler, two different species of Gyrodactylus — combined morphological and molecular investigations
Authors: Malmberg Göran , Collins Catherine , Cunningham Carey , Jalali Behiar 
Published: April 2007

AbstractThe paper deals with two morphologically similar but molecularly clearly different species of Gyrodactylus: G. derjavinoides sp. nov. on Salmo trutta trutta L. in Western Europe and G. derjavini Mikailov. 1975 collected on Salmo trutta caspius Kessler in Iran. The new species is described and its opisthaptoral hard parts compared to those of G. derjavini. Our molecular analysis of G. derjavinoides and G. derjavini confirmed that the morphological differences between them are species differences and not intraspecific variations. Phylogenetic analysis using the ITS rDNA region placed both species within the subgenus G. (Limnonephrotus) and within the G. wageneri-group, quite in accordance with morphological results. The two species, however, did not cluster as sister taxa. The correspondence between molecular-based clades within G. (Limnonephrotus) and the morphological shapes of marginal hooks within these clades are discussed. The importance of combined molecular and morphological analyses when describing or redescribing Gyrodactylus species is stressed.
Monitoring of Biochemical Parameters in Preterm Infants on Special Regime Feeding
Authors: Ljujić-Glišić Miroslava , Božinović-Prekajski Niveska 
Published: April 2007

Monitoring of Biochemical Parameters in Preterm Infants on Special Regime FeedingEnriched human milk may stimulate gain weight in preterm infants during the neonatal period. Aim is the biochemical assessment of preterm infants, fed by mother's milk fortificated with the special domestic formulapreImpamil during the first month of life. 80 preterm infants (45 male and 35 female), up to 36 weeks of gestation, BW less than 2500 g, started enteral intake in the first three days of life. Total volume intake was in range from 70 mL/kg first day, to 170-200 mL/kg after a 10thday of life. Mother's milk fortification was prepared as a 5% mixture solution ofpreImpamil. The dynamics of biochemical analyses started on the first day of study and was repeated once a week. We analysed levels of: total protein, albumin, prealbumin, transferin, urea, Ca ionised, P and alkaline phosphatase using standard biochemical methods. Statistical analyses were completed by ANOVA test, one-factorial analyses of variance. During monitoring the total protein level increased in the second week of life (p<0.01), as well as albumin (p<0.01). Prealbumin level increased, as well as transferin (p-NS). Initial level of ionised fraction of Ca was significantly lower (p<0.01) at the beginning of the study, compared to the rest. Serum level of P increased, as well as the level of alkaline phosphatase at the end of first and second week (p<0.01). Conclusion is that biochemical parameters, such as levels of protein and albumin, are important in the growth assessment of preterm infants on special feeding regimes.
Cover Picture: A Route to Self‐Organized Honeycomb Microstructured Polystyrene Films and Their Chemical Characterization by ToF‐SIMS Imaging (Adv. Funct. Mater. 7/2007)
Authors: Yunus S. , Delcorte A. , Poleunis C. , Bertrand P. , Bolognesi A. , Botta C. 
Published: April 2007

AbstractThe cover shows a composition of different characterization images of an auto‐organized polystyrene film obtained through breath‐figure imprinting, as reported by Sami Yunus and co‐workers on p. 1079. Water‐droplet condensation, represented as a synthetic perspective image (top), is responsible for ordered microstructuring during film formation. The following perspectives are taken from SEM and from three negative ToF‐SIMS images that allow deduction of the surface chemical composition. The background is an SEM picture of a polydimethylsiloxane molding of the self‐organized film.A new type of polymer compound that allows the formation of highly ordered microstructured films by casting from a volatile solvent in the presence of humidity, and its characterization by ToF‐SIMS (time‐of‐flight secondary‐ion mass spectrometry) are presented. A honeycomb structure is obtained by activation of 2,2,6,6‐tetramethyl‐1‐piperidinyloxyl (TEMPO)‐terminated polystyrene (PS) with p‐toluenesulfonic acid (PTSA). The mechanism of this activation reaction, leading to a more polar PS termination, is deduced from simple experiments and supported by ToF‐SIMS characterization. Positive and negative ToF‐SIMS imaging allows different chemical regions correlating to the film morphology to be distinguished. This new, straightforward activation process, together with ToF‐SIMS chemical imaging, provides a better understanding of the phenomena underlying the formation of these films by directly linking the role of polar terminations to the microscale self‐organization. This new method, transposable to other organic acids, suggests interesting new perspectives in the field of self‐organized chemical and topographical patterning.
An iron‐based reverse ATRP process for the living radical polymerization of acrylonitrile
Authors: Hou Chen , Ji Chunnuan , Qu Rongjun , Wang Chunhua , Sun Changmei , Zhou Wenying , Yu Mengmeng 
Published: April 2007

AbstractA hexa‐substituted ethane thermal iniferter, diethyl‐2,3‐dicyano‐2,3‐di(p‐tolyl) succinate (DCDTS), was firstly used as the initiator in the reverse atom transfer radical polymerization (RATRP) of acrylonitrile. FeCl3 coordinated by isophthalic acid (IA) was used as the catalyst in this system. The polymerization in N,N‐dimethylformamide not only shows the best control of molecular weight and its distribution but also provides rather rapid reaction rate with the ratio of [AN] : [DCDTS] : [FeCl3] : [IA] at 500 : 1 : 2 : 4. The polymers obtained were end‐functionalized by chlorine atom, and they were used as macroinitiators to proceed the chain extension polymerization in the presence of FeCl2/IA catalyst system via a conventional ATRP process and polyacrylonitrile obtained was with Mn = 39,260, PDI = 1.25. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007
Monte Carlo simulation of the compatibility of graft copolymer compatibilized two incompatible homopolymer blends: Effect of graft structure
Authors: Zhu Yutian , Ma Zengwei , Li Yunqi , Cui Jie , Jiang Wei 
Published: April 2007

AbstractCompatibility of graft copolymer compatibilized two incompatible homopolymer A and B blends was simulated by using Monte Carlo method in a two‐dimensional lattice model. The copolymers with various graft structures were introduced in order to study the effect of graft structure on the compatibility. Simulation results showed that incorporation of both A‐g‐B (A was backbone) and B‐g‐A (B was backbone) copolymers could much improve the compatibility of the blends. However, A‐g‐B copolymer was more effective to compatibilize the blend if homopolymer A formed dispersed phase. Furthermore, simulation results indicated that A‐g‐B copolymers tended to locate at the interface and anchor two immiscible components when the side chain is relatively long. However, most of A‐g‐B copolymers were likely to be dispersed into the dispersed homopolymer A phase domains if the side chains were relatively short. On the other hand, B‐g‐A copolymers tended to be dispersed into the matrix formed by homopolymer B. Moreover, it was found that more and more B‐g‐A copolymers were likely to form thin layers at the phase interface with decreasing the length of side chain. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007
Synthesis, characterisation, and chemical degradation of segmented polyurethanes with butylamine for chemical recycling
Authors: Elidrissi Abderahmane , Krim Ouassini , Ouslimane Samir , Berrabeh Mohamed , Touzani Rachid 
Published: April 2007

AbstractPolyurethane elastomers (PU) have been synthesized from polytetramethylene glycol 2000 (PTMG 2000); 4, 4′‐diphenylmethane diisocyanate (MDI) and 1, 4‐butanediol (BD) as chain extender. This synthesis has been done in two steps known as prepolymer methods. The concentration of soft segments and hydrogen attachment in the matrices, have been studied. The results show that the glass transition of the soft segment Tg(s) do not take any changes with the concentration of the soft segment in the matrices. Although, the glass transition temperature of the hard segment Tg(H) increases when the concentration of the hard segment increases in the matrices. In general, the properties of the polyurethane elastomers depend on the extenders nature, the synthesis methods, phase segregation etc. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007