bluuebunny/crossref_metadata_2025_split huggingface dataset:
Thickening Processes of Lamellar Crystal Monolayers of a Low‐Molecular‐Weight PEO Fraction on a Solid Surface
Authors: Zhai Xuemei , Zhang Gouliang , Ma Zhenpeng , Tang Xiongfeng , Wang Wei 
Published: March 2007

AbstractUsing hot‐stage atomic force microscopy, the thickening processes of monolayer crystals of PEO ($\overline M _{\rm n} $ = 5 000 g · mol−1 and $\overline M _{\rm w} /\overline M _{\rm n} $ = 1.008) from one‐folded (FC1) to extended‐chain (EC) lamellae are experimentally monitored at three temperatures: 50, 52, and 58 °C. At 50 °C some small areas in large FC1 crystals spontaneously thicken into EC crystals. At 52 °C the spontaneously thickened area further expands so as to inductively thicken the entire FC1 lamella into EC lamella. At 58 °C EC crystals first force the adjacent FC1 crystals to melt and then absorb the melted molecules to grow laterally into large EC lamellae till all FC1 lamellae vanish. The three thickening steps express the main thickening process of lamellar crystals from a metastable state to another metastable (or equilibrium) state. The possible mechanisms are discussed in the text.magnified image
An investigation of novolac resins by gel permeation chromatography
Authors: Montague P. G. , Peaker F. W. , Bosworth P. , Lemon P. 
Published: March 2007

AbstractIn the preparation of novolac resins, three possible dimers with slightly different molecular dimensions may be produced in the polymerisation reaction. Gel permeation studies were carried out on four novolac resins prepared using different acid catalysts, and the results indicated that the nature of the catalyst influences the type and quantity of dimer produced. The weight and number average molecular weights were also calculated from the chromatograms obtained.
Folding of tandem‐linked domains
Authors: Raman E. Prabhu , Barsegov Valeri , Klimov Dmitri K. 
Published: March 2007

AbstractOne of the factors, which influences protein folding in vivo, is a linkage of protein domains into multidomain tandems. However, relatively little is known about the impact of domain connectivity on protein folding mechanisms. In this article, we use coarse grained models of proteins to explore folding of tandem‐linked domains (TLD). We found TLD folding to follow two scenarios. In the first, the tandem connectivity produces relatively minor impact on folding and the mechanisms of folding of tandem‐linked and single domains remain similar. The second scenario involves qualitative changes in folding mechanism because of tandem linkage. As a result, protein domains, which fold via two‐state mechanism as single isolated domains, may form new stable intermediates when inserted into tandems. The new intermediates are created by topological constraints imposed by the linkers between domains. In both cases tandem linkage slows down folding. We propose that the impact of tandem connectivity can be minimized, if the terminal secondary structure elements (SSEs) are flexible. In particular, two factors appear to facilitate TLD folding: (1) the interactions between terminal SSE are poorly ordered in the folding transition state, whereas nonterminal SSE are better structured, (2) the interactions between terminal SSE are weak in the native state. We apply these findings to wild‐type proteins by examining experimental Φ‐value data and by performing all‐atom molecular dynamics simulations. We show that immunoglobulin‐like domains appear to utilize the factors, which minimize the impact of tandem connectivity on their folding. Several single domain proteins, which are likely to misfold in tandems, are also identified. Proteins 2007. © 2007 Wiley‐Liss, Inc.
Insights into unbinding mechanisms upon two mutations investigated by molecular dynamics study of GSK3β–axin complex: Role of packing hydrophobic residues
Authors: Zhang Na , Jiang Yongjun , Zou Jianwei , Zhuang Shulin , Jin Haixiao , Yu Qingsen 
Published: March 2007

AbstractGlycogen synthase kinase 3β (GSK 3β) is a key component of several cellular processes including Wnt and insulin signalling pathways. The interaction of GSK3β with scaffolding peptide axin is thought to be responsible for the effective phosphorylation of β‐catenin, the core effector of Wnt signaling, which has been linked with the occurrence of colon cancer and melanoma. It has been demonstrated that the binding of axin to GSK3β is abolished by the single‐point mutation of Val267 to Gly (V267G) in GSK3β or Leu392 to Pro (L392P) in axin. Molecular dynamics (MD) simulations were performed on wild type (WT), V267G mutant and L392P one to elucidate the two unbinding mechanisms that occur through different pathways. Besides, rough energy and residue‐based energy decomposition were calculated by MM_GBSA (molecular mechanical Generalized_Born surface area) approach to illuminate the instability of the two mutants. The MD simulations of the two mutants and WT reveal that the structure of GSK3β remains unchanged, while axin moves away from the interfacial hydrophobic pockets in both two mutants. Axin exhibits positional shift in V267G mutant, whereas, losing the hydrogen bonds that are indispensable for stabilizing the helix structure of wild type axin, the helix of axin is distorted in L392P mutant. To conclude, both two mutants destroy the hydrophobic interaction that is essential to the stability of GSK3β‐axin complex. Proteins 2007. © 2007 Wiley‐Liss, Inc.
Effect of fungal damage on seed composition and quality of soybeans
Authors: Wilson R. F. , Novitzky W. P. , Fenner G. P. 
Published: March 2007

AbstractFungal damage caused by pathogens such asFusarium, Cercospora, andPhomopsis can have a devastating impact on physical quality and farm price of soybeans. In some price‐discount schedules, soybeans may be rejected with as low as 5% fungal damage. Although the severity of this problem varies throughout the United States, millions of bushels of fungus‐damaged soybeans may be destroyed annually due to a lack of markets. The effect of fungal damage on seed composition was evaluated to assess potential utility of highly damaged soybeans. Graded samples of the cv. Centennial soybean were dried to 10% moisture and blended on a proportional weight basis to derive a series of treatments from 0 to 80% fungal damage. A positive correlation was found between fungal damage and both protein and oil concentrations. This condition was attributed to loss of residual seed mass. As a result, the protein concentration of defatted meal increased from ca. 54 to 66% over the range of 0 to 80% fungal damage. Mycotoxin contamination appeared to be insignificant in these high‐protein meals. Fixed colors in bleached, alkali refined oils were intensified by heat treatment prior to extraction. No significant differences, however, were noted in total polar lipid content, phospholipid, or tocopherol composition among treatments of up to 20% fungal damage. Oils from treatments of more than 40% fungal damage were more severely oxidized and could not be degummed effectively. These data suggest that fungus‐damaged soybeans may be blended with high‐quality soybeans to alleviate the chemical symptoms associated with unacceptable product quality. Thus, through various blend ratios, processors may consider using fungus‐damaged soybeans to gain economic advantage, especially when high‐quality soybeans have lower protein concentration.
Water‐in‐oil microemulsion as mobile phase in thin‐layer chromatographic retention studies of anions
Authors: Mohammad Ali , Tiwari Sharad , Chahar Jay Pal Singh , Kumar Sanjeev 
Published: March 2007

AbstractA water‐in‐oil (W/O) microemulsion, consisting of sodium dodecyl sulphate (SDS)/1‐pentanol/water/heptane, has been used as mobile phase for the separation of inorganic anions from their binary mixtures, for example, IO4−‐NO2−, IO4−‐BrO3−, IO4−‐I−, MnO4−‐BrO3−, MnO4−‐NO2−, and MnO4−‐Br−. The weight ratio, SDS/n‐pentanol was kept constant at 1/2.46 for all compositions. The retention efficiency of anions on layers of silica gel G, alumina, microcrystalline cellulose, kieselguhr G, and mixtures of kieselguhr and cellulose in 4:1 and 3:2 ratios has been examined with the W/O microemulsion system as a mobile phase. Thin layers of kieselguhr were most useful for differential migration of anions. Quantitative separation of IO4− from accompanying ions, limits of identification, and dilution of few anions are reported. The effects of amines, phenols, and heavy metals on the separation efficacy of IO4− also have been investigated.
Natural antioxidants produced in oxidized lipid/amino acid browning reactions
Authors: Alaiz Manuel , Zamora Rosario , Hidalgo Francisco J. 
Published: March 2007

Abstract1‐Substituted pyrroles (1 and2) and1‐substituted 2‐(1′‐hydroxypropyl)pyrroles (3–5) were produced in reactions between a lipid peroxidation product, 4,5(E)‐epoxy‐2(E)‐heptenal, and the amino acid lysine. The antioxidative activity of compounds1–5 was studied. Oxidative stability was evaluated in refined soybean oil containing compounds1–5, butylated hydroxytoluene (BHT),n‐propyl gallate orl‐lysine, at concentrations of 50–200 ppm. Oils were either oxidized at 60°C and oxidation products determined by the thiobarbituric acid‐reactive substances assay, or they were oxidized at 110°C by the Rancimat method. Although both methods gave similar results, greater differences were observed at 60°C than at 110°C. Addition of compounds1–5,l‐lysine, BHT, and propyl gallate significantly (P<0.01) protected the oil against oxidation. The effectiveness order found was:l‐lysine << compounds3–4 < compounds1–2 < compound5 ≈ BHT << propyl gallate.
Etiological heterogeneity in the development of antisocial behavior: the Virginia Twin Study of Adolescent Behavioral Development and the Young Adult Follow-Up
Authors: SILBERG JUDY L. , RUTTER MICHAEL , TRACY KELLY , MAES HERMINE H. , EAVES LINDON 
Published: March 2007

ABSTRACTBackgroundLongitudinal, genetically informed, prospective data collected on a large population of male twins (n=1037) were used to examine developmental differences in the etiology of antisocial behavior.MethodAnalyses were carried out on both mother- and child-reported symptoms of conduct disorder (CD) in 10- to 17-year-old twins from the Virginia Twin Study of Adolescent Behavioral Development (VTSABD) and self-reported antisocial behavior by the twins as young adults from the Young Adult Follow-Up (YAFU) study.ResultsThe following trends were identified: (1) a single genetic factor influencing antisocial behavior beginning at age 10 through young adulthood (‘life-course persistent’); (2) a shared-environmental effect beginning in adolescence (‘adolescent-onset’); (3) a transient genetic effect at puberty; and (4) a genetic influence specific to adult antisocial behavior.ConclusionsOverall, these etiological findings are consistent with predictions from Moffitt's developmental theory of antisocial behavior. The genetic effect at puberty at ages 12–15 is also consistent with a genetically mediated influence on the timing of puberty affecting the expression of genetic differences in antisocial outcomes.
Anasthesia for fetal surgery
Authors: SPIELMAN F. J. , SEEDS J. W. , CORKE B. C. 
Published: March 2007

SummaryAnasthesia for fetal surgery is described as used for thirteen procedures in seven patients. Analgesia was accomplished by local infiltration of lignocaine 1% by the surgeons and small incremental doses of intravenous medication by the anasthetist as needed to make the mother comfortable and reduce fetal movement. There were no maternal or fetal complications. Ethical issues of this therapy are described.
Forum Aminophylline reversal of diazepam sedation
Authors: Arvidsson S. , Niemand D. , Martinell S. , Ekström‐Jodal B. 
Published: March 2007

SummaryA double‐blind randomised study was performed to investigate whether aminophylline reversed the sedative effect of diazepam. Thirty‐two patients undergoing genito‐urinary surgery with spinal or topical anasthesia were given diazepam to maintain a state of deep sedation. Postoperatively patients received either aminophylline (60–120 mg) or physiological saline intravenously. The aminophylline group showed a rapid reversal of sedation. which persisted throughout the observation period of 2 hours. No such effect was seen in the patients who received saline and the difference was still obvious after 2 hours. It is concluded that aminophylline is a potent antagonist to the sedative effect of diazepam.
Pupillometer* for use during anasthesia
Authors: ASBURY A. J. , LEAR G. A. , WORTLEY D. 
Published: March 2007

SummaryThis paper presents the design for a pupillometer based on a fixed focal length microscope; it is suitable for use during anasthesia. The pupillometer has been tested and found to give reliable results. A certain amount of practice is necessary to make measurements quickly. The pupillometer was designed to allow the study of pupil diameter in relation to ‘depth of anasthesia’.
The validity of informed consent in a clinical study
Authors: GOODMAN N. W. , COOPER G. M. , MALINS A. F. , PRYS‐ROBERTS C. 
Published: March 2007

SummaryPatients, aged 36 to 78 years, who had participated in two studies that included the ventilatory effects of postoperative analgesia, returned a questionnaire canvassing their views of the procedure for obtaining consent and the conduct of the study. Fourteen of 18 patients from one study, and all 18 from the second, returned their questionnaires. Thirty of the 32 patients were satisfied with the pre‐operative explanation. Eleven patients felt obliged to take part, not because of coercion, but from a sense of duty to others. The breathing tests caused discomfort to eight patients but only one of them found this more than expected from the pre‐operative explanation. Only two patients, both in the second study, said that they would not volunteer again for a similar study. There was no suggestion that the age of the patient or the fact that they were undergoing major surgery had any influence on their attitudes or comprehension. It may be prudent to use this type of questionnaire to evaluate the response of patients to some research projects.
Training for day‐case dental anaesthesia. Oxygen saturation during general anaesthesia administered by dental undergraduates
Authors: Walsh* J.F. 
Published: March 2007

SummarySixty‐seven patients undergoing general anaesthesia for exodontia as outpatients were studied in order to measure the levels of oxygen saturation. Both the anaesthesia and extractions were performed by fourth year dental undergraduates working under direct supervision. Falls in oxygen saturation in excess of 5% were found in three groups of patients receiving 20%, 25%, and 30% oxygen in the inspired mixture.
Induction of T‐cell activation or anergy determined by the combination of intensity and duration of T‐cell receptor stimulation, and sequential induction in an individual cell
Authors: Yamamoto Tomohiro , Hattori Makoto , Yoshida Tadashi 
Published: March 2007

SummaryIt has been shown that anergic T cells have important roles in peripheral tolerance, although the precise mechanism for inducing anergy is still unclear. We analysed the kinetics of anergy induction at an individual cell level by flow cytometry. We first successfully obtained T helper type 1 (Th1) cells that had been made uniform with the level of interferon‐γ (IFN‐γ) production induced by antigen stimulation. We then used these Th1 cells to evaluate the degree of anergy for each Th1 cell treated with an anti‐CD3 monoclonal antibody according to the level of IFN‐γ secretion. Our results demonstrate that anergic stimulation could induce both activation and anergy, depending on the duration and intensity of stimulation at the level of an individual cell. Each Th1 cell was first activated and then gradually became anergic depending on the duration of stimulation. The duration of the stimulus required for inducing anergy became shorter as the intensity of stimulation became stronger. We also show that the calcineurin signal controlled the induction of activation or anergy depending on the activity. This study contributes to better understanding of the precise mechanism for inducing T‐cell anergy.
Polymorphisms in genes regulating androgen activity among prostate cancer low‐risk Inuit men and high‐risk Scandinavians
Authors: Giwercman Charlotte , Giwercman Aleksander , Pedersen Henning Sloth , Toft Gunnar , Lundin Kristina , Bonde Jens‐Peter , Giwercman Yvonne Lundberg 
Published: March 2007

SummaryIn Greenland, with a male population of approximately 30 000 individuals, the incidence of prostate cancer is extremely low with only three cases described during the period 1988–1997. Polymorphisms related to high androgen metabolism and/or response in the 5α‐reductase type 2 (SRD5A2) and the androgen receptor (AR) genes, respectively, have been linked to prostate cancer. Our objective was to analyse whether the distribution of these polymorphisms differed between the prostate cancer low‐risk population from Greenland and the relatively high‐risk Swedish male population. The SRD5A2 polymorphisms A49T, V89L and R227Q, and the CAG and GGN repeats in the AR gene were genotyped in leucocyte DNA from 196 Greenlanders and 305 Swedish military conscripts. All subjects had the wild‐type R/R genotype of the R227Q marker. The high‐activity variants A49T A/T and V89L V/V occurred less frequently (2% vs. 5%, p = 0.048 and 33% vs. 46%, p = 0.0027) in Greenland compared with Sweden, whereas the low‐activity L/L genotype was more frequent in Greenland (24% vs. 13%, p = 0.0024). Greenlanders also had longer AR CAG repeats than the Swedish population (median 24 vs 22, p < 0.0005). Greenlanders also had a higher frequency of the GGN = 23 allele (85% vs. 54%, p < 0.0001). Our results suggest that Greenlanders are genetically predisposed to a lower activity in testosterone to 5α‐dihydrotestosterone turnover and to lower AR activity, which, at least partly, could explain their low incidence of prostate cancer.
Enhanced Immunogenicity of Modified Hepatitis B Virus Core Particle Fused with Multiepitopes of Foot‐and‐Mouth Disease Virus
Authors: Zhang Y.‐L. , Guo Y.‐J. , Wang K.‐Y. , Lu K. , Li K. , Zhu Y. , Sun S.‐H. 
Published: March 2007

Abstract Hepatitis B virus core (HBc) particles, self‐assemble into capsid particles and are extremely immunogenic, hold promise as an immune‐enhancing vaccine carrier for heterologous antigens. However, formation of virus‐like particles (VLP) can be restricted by size and structure of heterlogous antigens. In the study, we investigated formation of VLP by modified HBc fused with specified foot‐and‐mouth disease virus (FMDV) multiepitopes and evaluated their immune effects. Firstly, three HBc display vectors (pHBc1, pHBc2 and pHBc3) were constructed by deletions of different lengths within the HBc c/e1 region: 75–78 amino acid (aa), 75–80 aa and 75–82 aa respectively. Secondly, we inserted different compositions of FMDV multiepitopes, BT [VP1(141–160)–VP4(21–40)] and BTB [VP1(141–160)–VP4(21–40)–VP1(141–160)], into modified regions. As a result, only plasmid pHBc3‐BTB of six recombinant vectors was expressed as soluble protein, which resulted in the formation of complete VLP confirmed by electron microscopy. Recombinant VLP could be taken up by cells and presented in vitro and in vivo. Furthermore, the modified VLP displayed a significantly stronger immunogenicity than other five recombinant proteins and GST‐BTB with a higher titer of peptide‐specific and virus‐specific antibody, elevated IFN‐γ and interleukin‐4 production, especially enhanced lymphocyte proliferation. The results encourage further work towards the development of FMDV vaccines using hepatitis B virus core particles fused with FMDV epitopes.
The effects of metformin and glibenclamide on glucose metabolism, counter‐regulatory hormones and cardiovascular responses in women with Type 2 diabetes during exercise of moderate intensity
Authors: Cunha M. R. , Da Silva M. E. R. , Machado H. A. , Fukui R. T. , Correa M. R. S. , Santos R. F. , Wajchenberg B. L. , Rondon M. U. P. B. , Negrão C. E. , Ursich M. J. M. 
Published: March 2007

AbstractAims  To compare the effects of metformin and glibenclamide on cardiovascular, metabolic and hormonal parameters during exercise of moderate intensity performed in the postprandial state, in women with Type 2 diabetes.Methods  Ten patients treated with metformin, 10 with glibenclamide and 10 control subjects (C) exercised on a bicycle ergometer at 50% of oxygen uptake (VO2) peak for 45 min. Cardiovascular, blood metabolic and hormonal parameters were determined at times −60 min (fasting), 0, +15, +30, +45 min (exercise) and at +60, +90 min (recovery). Thirty minutes prior to exercise, participants consumed a standard breakfast. Patients with diabetes took metformin or glibenclamide before the meal.Results  Systolic and diastolic blood pressure and plasma glucose were higher in both diabetic groups, for the whole experiment. Blood glucose did not change during exercise in the three groups and increased at recovery only in the control group. Plasma glucagon concentrations at the end of exercise and recovery, and plasma lactate concentrations at recovery were higher in the metformin group. Insulin, noradrenaline, growth hormone, cortisol and free fatty acid responses were similar in all three groups.Conclusions  Our results suggest that the usual dose of glibenclamide and metformin can be taken safely before postprandial exercise of moderate intensity without affecting cardiovascular, metabolic and hormonal responses. However, after exercise, glibenclamide and metformin prevent the normal rise in blood glucose and metformin delays the fall in plasma lactate concentrations.
Morphometry of Dorsal Raphe Nucleus Serotonergic Neurons in Alcoholism
Authors: Underwood Mark D. , Mann J. John , Arango Victoria 
Published: March 2007

Background: Reduced serotonergic function is hypothesized in alcohol abuse and dependence. Serotonergic innervation of the cortex arises predominantly from the dorsal raphe nucleus (DRN). We sought to determine the number and morphometric characteristics of DRN serotonergic neurons postmortem in alcoholic individuals (n=9; age: 16–66years; 8M:1F) compared with psychiatrically normal, nonalcoholic controls (n=6; age: 17–74 years; 4M:2F).Methods: Brainstems were collected at autopsy, fixed and cryoprotected. Alcohol dependence or abuse was determined by psychological autopsy (DSM‐IV), the presence of liver fatty changes or cirrhosis and/or high blood alcohol level. Tissue was sectioned at 50 μm (−25°C). A series of 1:10 sections was immunoreacted with antiserum to tryptophan hydroxylase (TPH), the rate‐limiting enzyme in the biosynthesis of serotonin. The total number of TPH‐immunoreactive (IR) DRN neurons was determined by stereology. Neuron morphometry indices were determined using a video‐based imaging system attached to a microscope. We identified TPH‐IR neurons every 1,000 μm in each brainstem and measured neuron area, total cross sectional neuron area, and the total area and density of immunolabeled processes.Results: Dorsal raphe nucleus neuron number (controls: 80,386±10,238; alcoholic individuals: 85,884±12,478) was not different between groups but TPH‐IR was greater in alcoholic individuals throughout the rostrocaudal extent of the DRN. The volume of the DRN was 66±9 mm3 in controls and 55±5 mm3 in alcoholic individuals (p>0.05). The average size of DRN neurons did not differ between groups (353±12 μm2 for controls vs 360±15 μm2 for alcoholic subjects). However, the area occupied by neuron processes (area of processes/DRN area) was 2.2‐fold greater in alcoholic individuals compared with controls (p<0.05).Conclusions: The increased area occupied by neuron processes in alcoholic individuals may represent sprouting and, together with greater TPH‐IR, be a compensatory response to impaired serotonergic transmission or cumulative effects of alcohol on the serotonin system.