bluuebunny/crossref_metadata_2025_split huggingface dataset:
Estrous‐cycle‐dependent hippocampal levels of signaling proteins
Authors: Diao Wei‐Fei , Höger Harald , Chen Wei‐Qiang , Pollak Arnold , Lubec Gert 
Published: April 2007

AbstractThere is information that proteins are expressed in a hormone‐dependent manner but no systematic study on this subject has been carried out to the best of our knowledge. We therefore decided to investigate protein expression in a well‐studied brain area, the hippocampus, in female rats at various phases of the estrous cycle and in male rats. Male and female OFA Sprague‐Dawley rats were used in the studies and estrous phases were determined using vaginal smears and females were grouped according to PE, E, ME, and DE. Hippocampal tissue was taken, proteins extracted, run on two‐dimensional gel electrophoresis and proteins were identified by mass spectrometry methods (MALDI‐TOF‐TOF and nano‐LC‐ESI‐MS/MS). Individual signaling protein levels quantified by specific software were shown to depend on sex and phase of the estrous cycle. These include NG,NG‐dimethylarginine dimethylaminohydrolase for nitric oxide signaling, stathmin, SH3 domain protein 2A, SH3 domain protein 2B, S100 calcium binding protein B, calcyclin‐binding protein, Syndapin I, GTPase HRas, guanine nucleotide‐binding proteins, septin 8, G‐septin alpha, phosphtidylethanolamine‐binding protein, several protein phosphatases. Results from this study, although increasing complexity of protein knowledge, may help to design further investigations at the protein level and may assist to interpret literature on protein expression and brain protein levels. © 2007 Wiley‐Liss, Inc.
Influence of age on BDNF modulation of hippocampal synaptic transmission: Interplay with adenosine A2A receptors
Authors: Diógenes Maria J. , Assaife‐Lopes Natália , Pinto‐Duarte António , Ribeiro Joaquim A. , Sebastião Ana M. 
Published: April 2007

AbstractWe previously reported that adenosine, through A2A receptor activation, potentiates synaptic actions of brain‐derived neurotrophic factor (BDNF) in the hippocampus of infant (3–4 weeks) rats. Since A2A‐receptor‐mediated actions are more evident in old than in young rats and since the therapeutic potential for BDNF‐based strategies is greater in old subjects, we now evaluated synaptic actions of BDNF and the levels of TrkB receptors and of adenosine A2A receptors in the hippocampus of three groups of adult rats: young adults (10–16 weeks), old adults (36–38 weeks), and aged (70–80 weeks), as well as in one group of infant (3–4 weeks) rats. BDNF (20 ng/ml) enhances field excitatory postsynaptic potentials recorded from the hippocampus of young adults and aged rats, an action triggered by adenosine A2A receptor activation, since it was blocked by the A2A receptor antagonist, ZM 241385. In the other groups of animals BDNF (20 ng/ml) was virtually devoid of action on synaptic transmission. Western blot analysis of receptor density shows decreased amounts of TrkB receptors in old adults and aged rats, whereas A2A receptor levels assayed by ligand binding are enhanced in the hippocampus of old adults and aged rats. It is concluded that age‐related changes in the density of TrkB receptors and of adenosine A2A receptors may be responsible for a nonmonotonous variation of BDNF actions on synaptic transmission in the hippocampus. © 2007 Wiley‐Liss, Inc.
Improved short‐term engraftment of lentivirally versus gammaretrovirally transduced allogeneic canine repopulating cells
Authors: Neff Tobias , Gerull Sabine , Peterson Laura J. , Kiem Hans‐Peter 
Published: April 2007

AbstractGammaretroviral vectors require cell division for efficient transduction. Thus, extended cell culture times are necessary for efficient transduction with gammaretroviral vectors, which in turn can lead to stem cell loss and impaired engraftment. Lentiviral vectors transduce nondividing cells and are therefore able to transduce stem cells in short transduction protocols. Here, we compared the short‐term engraftment of lentivirally and gammaretrovirally transduced canine allogeneic DLA‐matched littermate cells. A reduced conditioning regimen of 400 cGy total body irradiation was used in preparation for clinical studies. Two dogs received a graft of gammaretrovirally transduced CD34‐selected cells. CD34+ cells were prestimulated for 30 h and then exposed twice to concentrated RD114 pseudotype vector. Three dogs received lentivirally transduced CD34‐selected cells. Cells were transduced overnight with concentrated VSV‐G pseudotype lentiviral vector. The animals in the lentiviral group showed a significantly faster granulocyte recovery. VNTR analysis 40–50 days after transplantation revealed higher donor chimerism for the lentiviral group compared to the retroviral group. These data suggest that short lentiviral transduction protocols may be superior to extended gammaretroviral transduction protocols with respect to engraftment potential of transduced CD34+ hematopoietic repopulating cells. Copyright © 2007 John Wiley & Sons, Ltd.
Venous thromboembolism prophylaxis in emergency department admissions
Authors: Levine Robert L. , Hergenroeder Georgene W. , Miller Charles C. , Davies Al 
Published: April 2007

AbstractBACKGROUNDGuidelines for venous thromboembolism prophylaxis exist, yet prophylaxis is underutilized and inadequately studied in the context of emergency department admissions.OBJECTIVEThis study aimed to measure the rate of venous thromboembolism prophylaxis in emergency department hospitalizations.DESIGNProspective observational study.SETTINGUrban, teaching hospital.PATIENTSAdult emergency department admissionsINTERVENTIONAlternating admissions through the emergency department over 1 month were reviewed. Exclusion criteria were: requiring full anticoagulation, hemodialysis, length of stay less than 2 days, psychiatric admission, and primary physician declined review. An established risk assessment tool classified thromboembolism risk. Appropriate prophylaxis was defined as currently accepted medical or mechanical prophylaxis if in need or no prophylaxis if not indicated.MEASUREMENTSFactors associated with prophylaxis were considered significant if P < .05.RESULTSOf 254 patients, 201 (79%) had indications for prophylaxis, of whom 65 (32%) received it. Seventy‐eight percent of prophylaxis orders were written in the first day of hospitalization. Factors related to increased use of prophylaxis included use of standard order sets (OR = 3, P < .009) and increased risk of venous thromboembolism (P < .0001). Factors related to underuse included primary cardiovascular diagnosis (OR = 0.18, P < .0001) and age (OR = 0.97, P < .0001). Eighteen of 26 patients admitted for whom standard order sets were used (69%) received appropriate prophylaxis (P = .01).CONCLUSIONSPatients admitted through the emergency department are at high risk of venous thromboembolism. Despite this, venous thromboembolism prophylaxis is underutilized and rarely started after the first day of hospitalization. Use of admission standard order sets on admission from the emergency department may increase thromboembolic prophylaxis. Journal of Hospital Medicine 2007;2:79–85. © 2007 of Hospital Medicine.
The effects of deforestation on the hydrological cycle in Amazonia: a review on scale and resolution
Authors: D'Almeida Cassiano , Vörösmarty Charles J. , Hurtt George C. , Marengo José A. , Dingman S. Lawrence , Keim Barry D. 
Published: April 2007

AbstractThis paper reviews the effects of deforestation on the hydrological cycle in Amazonia according to recent modeling and observational studies performed within different spatial scales and resolutions. The predictions that follow from future scenarios of a complete deforestation in the region point to a restrained water cycle, while the simulated effects of small, disturbed areas show a contrasting tendency. Differences between coarsely spatially averaged observations and finely sampled data sets have also been encountered. These contrasts are only partially explained by the different spatial resolutions among models and observations, since they seem to be further associated with the weakening of precipitation recycling under scenarios of extensive deforestation and with the potential intensification of convection over areas of land‐surface heterogeneity. Therefore, intrinsic and interrelated scale and heterogeneity dependencies on the impact of deforestation in Amazonia on the hydrological cycle are revealed and the acknowledgement of the relevance of these dependencies sets a few challenges for the future. Copyright © 2007 Royal Meteorological Society
Rheological properties of batter systems containing different combinations of flours and hydrocolloids
Authors: Xue Jun , Ngadi Michael 
Published: April 2007

AbstractThe rheological properties of batters formulated using different combinations of wheat, corn, and rice flours with two types of hydrocolloids, namely methylcellulose (0.5%, 1% and 1.5%) or xanthan gum (0.2%), were studied. Control samples were formulated with combinations of flours without the added hydrocolloids. The effects of hydrocolloids on rheological characteristics of the batter systems were measured using a controlled stress rheometer at a temperature of 15 °C. The effects of hydrocolloids on dynamic viscoelastic parameters as functions of temperatures were evaluated. All the batters showed shear thinning behaviour with flow behaviour indices in the range 0.34–0.67. Addition of xanthan gum lowered the flow index values, imparting a higher degree of pseudoplasticity to the batter samples compared to methylcellulose. The consistency index of the control batter samples varied from 0.46 to 69.2 Pa sn. Addition of xanthan gum or methylcellulose significantly increased the batter consistency index value. The gums changed the onset temperature of structure development, and the storage (G′max) and loss moduli (G″max) of the batter systems. However, no statistically significant effects were observed on the peak temperature of batter systems in which the G′ reached a maximum value. Xanthan gum increased both G′max and G″max, whereas at higher concentrations methylcellulose increased G′max but lowered G″max. Copyright © 2007 Society of Chemical Industry
Vacuum ultraviolet laser‐induced fluorescence kinetic study of the reactions of Cl atoms with fluoroalkenes (CxF2x+1CHCH2, x = 1,2,4, 6, and 8) at low pressures
Authors: Takahashi Kenshi , Iwasaki Erika , Nakayama Tomoki , Matsumi Yutaka , Wallington Timothy J. 
Published: April 2007

AbstractPulsed laser photolysis/vacuum ultraviolet laser‐induced fluorescence techniques were used to measure rate coefficients for Cl atom reactions with a series of fluoroalkenes (CxF2x+1CHCH2, x = 1,2,4,6,8) in 6–10 Torr of CF4 diluent at 295 ± 2 K. Rate coefficients (units of 10−11 cm3 molecule−1s−1) of 4.49 ± 0.64, 6.58 ± 0.59, 8.91 ± 0.58, 9.27 ± 0.64, and 9.00 ± 0.87 were determined for CxF2x+1CHCH2 with x = 1,2,4,6, and 8, respectively. In 6–10 Torr of CF4 diluent, the kinetics of the title reactions are at, or near, the high‐pressure limit for x = 4, 6, and 8, approximately 30% below the high‐pressure limit for x = 2, and approximately 50% below the high‐pressure limit for x = 1. © 2007 Wiley Periodicals, Inc. Int J Chem Kinet 39: 328–332, 2007
Analysis of the combustion reaction of carbon and lignite char with ignition and extinction phenomena: Shrinking sphere model
Authors: Gupta Parthapratim , Sadhukhan Anup Kumar , Saha Ranajit Kumar 
Published: April 2007

AbstractSingle‐particle combustion of carbon and lignite char is analyzed in the present work using a generalized shrinking sphere model. Finite volume method (FVM), which was earlier employed by the authors in solving such moving boundary problems involving single particle analysis of general fluid–solid noncatalytic reactions, has been used in this work to solve the transient mass and energy balance equations. The computed results are compared with published experimental data of fluidized‐bed combustion of lignite char. The effects of various parameters like bulk temperature, initial particle temperature, initial particle radius, etc. are examined on the dynamics of combustion of carbon and lignite char. The phenomena of ignition and extinction are also investigated. The importance of nonequimolar diffusion in the combustion reaction has also been analyzed. © 2007 Wiley Periodicals, Inc. Int J Chem Kinet 39: 307–319, 2007
Synthesis of porphyrins bearing uracyl groups and their assembly induced by melamine derivatives
Authors: Arai Satoshi , Ohshiro Hiroki , Nishide Hiroyuki , Takeoka Shinji 
Published: April 2007

AbstractSelf‐assembled porphyrins via noncovalent bonding have attracted wide‐ranging researchers in material science. We reported herein the synthesis of the tetraphenyl porphyrin derivatives bearing uracyl groups as acceptor–donor–acceptor (ADA) type hydrogen bonding units, through the condensation of 5,10‐ or 5,15‐bis (3‐amino‐4‐ethylhexylphenyl) porphyrin derivatives with 6‐carboxyuracyl derivatives. When two porphyrins having uracyl groups at the different substituted positions were respectively mixed with a melamine derivative in benzene, 1H NMR spectra showed that the 5,15 substituted uracyl porphyrin formed a hydrogen‐bonded suprastructure with the melamine derivative as a complementary molecule to the uracyl moiety, although the other 5,10‐substituted uracylporphyrin could not form such a structure. The SEM observation indicated that the mixture with the 5,15‐substituted uracyl porphyrin and the melamine with long alkyl chains formed a sheet‐like structure. Copyright © 2007 John Wiley & Sons, Ltd.
Use of RNA interference to elucidate the effect of MYCN on cell cycle in neuroblastoma
Authors: Woo Chan‐Wook , Tan Fei , Cassano Hope , Lee JungHwa , Lee Kwang Chul , Thiele Carol J. 
Published: April 2007

AbstractBackgroundMYCN amplification marks poor prognosis in neuroblastoma (NB) tumors. In evaluating the mechanisms by which retinoic acid (RA) or nerve growth factor (NGF) decrease cell number in MYCN amplified NB cells, we have identified a number of proteins whose expression either decreases (E2F, CDC2, CDK6, cyclin dependent kinase activity) or increases (p27) in association with a decrease in MYCN expression. However, it was still unclear which were MYCN dependent effects or not.ProcedureThis study aimed to determine which changes in cell cycle gene expression are modulated as a consequence of the decrease in MYCN. We silenced MYCN expression using siRNA targeted to the coding region of MYCN. Then, by using siRNA transient transfections, we analyzed the change of cell cycle related genes and cell cycle in MYCN amplified NB cell lines.ResultsWe demonstrate that expression of MYCN can be suppressed by almost 60% in MYCN amplified NB cell using siRNAs targeted to MYCN. Functionally, the decrease in MYCN leads to a decrease in cells in the S‐phase of the cell cycle. Decreases in MYCN are associated with decreases in E2F1‐2 and ID2 along with increases in p27 protein levels by post‐transcriptional modification. Moreover, we find that a decrease in MYCN is accompanied by a decrease in cdk6 mRNA and protein expression.ConclusionsThese results show that E2F and ID2 expression is associated with MYCN regulation and that cdk6 is a possible new transcriptional target of MYCN. Pediatr Blood Cancer 2008;50:208–212. © 2007 Wiley‐Liss, Inc.
Initial testing (stage 1) of the proteasome inhibitor bortezomib by the pediatric preclinical testing program
Authors: Houghton Peter J. , Morton Christopher L. , Kolb E. Anders , Lock Richard , Carol Hernan , Reynolds C. Patrick , Keshelava Nino , Maris John M. , Keir Stephen T. , Wu Jianrong , Smith Malcolm A. 
Published: April 2007

AbstractBackgroundBortezomib is a proteasome inhibitor that has been approved by FDA for the treatment of multiple myeloma and that has completed phase 1 testing in children. The purpose of the current study was to evaluate the antitumor activity of bortezomib against the in vitro and in vivo childhood cancer preclinical models of the Pediatric Preclinical Testing Program (PPTP).ProceduresBortezomib was tested against the PPTP in vitro panel at concentrations ranging from 0.1 nM to 1.0 µM and was tested in vivo at a dose of 1 mg/kg for a planned duration of 6 weeks.ResultsBortezomib was uniformly active against the PPTP's in vitro panel, with a median IC50 of 23 nM and with a steep dose–response curve. The four acute lymphoblastic leukemia (ALL) cell lines had significantly lower IC50 values compared to the remaining lines of the in vitro panel. Limited in vivo activity was observed for bortezomib against the solid tumor xenografts tested, with one line meeting criteria for intermediate activity for the time to event measure and with the remaining lines showing low activity for this measure. Bortezomib demonstrated in vivo activity against the ALL panel, inducing two complete and two partial responses among seven evaluable lines.ConclusionsAdministered at its MTD in mice, bortezomib demonstrated activity against selected lines of the PPTP's ALL in vivo panel. Further studies are indicated to determine the activity of bortezomib when combined with standard agents to treat childhood ALL. Pediatr Blood Cancer 2008;50:37–45. © 2007 Wiley‐Liss, Inc.
Study on change in the degree of polymerisation of bacterial cellulose produced by Acetobacter xylinum during its cultivation
Authors: Okajima Kunihiko , Matsuda Yukiko , Kamide Kenji 
Published: April 2007

AbstractAn attempt was made to clarify the change in the viscosity‐average degree of polymerisation (Pv) of a bacterial cellulose within a cell cycle using the technique of synchronous static culture conditions of an acetic acid bacterium (Acetobacter xylinum), formerly established by us (British Polymer J., 22 (1990) 167). Under these conditions the yield of bacterial cellulose and its Pv were found to increase stepwise within a cell cycle. Furthermore, Pv of the cellulose increased rapidly in the cultivation stage where the production rate of cellulose is quite low. As soon as the cultivation went into the first stage where Pv of the bacterial cellulose increased very slowly, its infrared absorbance for C—O stretching with parallel infrared dichroism strongly increased. The maximum Pv attainable for cellulose obtained under the synchronous culture conditions used here was c. 1500. The time length of a cell cycle for the synchronous culture was controlled by adjusting the air supply.
On the nature of junction zones in gelatin gels
Authors: Mel'Nichenko Yu. B. , Gomza Yu. P. , Shilov V. V. , Osipov S. I. 
Published: April 2007

AbstractThe structural modifications and the phase state of the gelatin matrix during the sol‐gel transition and gelatin gel deswelling were studied by optical rotation and wide‐angle X‐ray scattering (WAXS) methods. It is shown that the quenching of a solution results in rapid renaturation of macromolecular fragments of gelatin and in collagen‐like structures forming junction zones in the polymer network. Microcrystallites in the polymer matrix of gelatin gels were not revealed which shows that the aggregation of renaturated helices and the formation of collagen‐like fibrillar crystals do not occur. However, the crystalline phase appears upon gel drying or its deswelling in a nonsolvent.
Radical polymerization of methyl acrylate initiated by styrene‐arsenic sulphide complex
Authors: Shukla Prerna , Srivastava A. K. 
Published: April 2007

AbstractA styrene‐arsenic sulphide complex in DMSO at 85 ± 0.1°C initiates radical polymerization of methyl acrylate over 90 min under a N2 blanket. Conversion reaches 83% without gelation and results in the formation of polymer having average degree of polymerization 710. Analysis of the kinetic data (up to 29% conversion) indicates that the system follows ideal kinetics. The reaction is retarded by hydroquinone. The overall activation energy and value of k2p/kt are 96 kJ mol−1 and 6.9 × 10−3 litre mol−1 s−1, respectively.
A simple procedure for assessing the protective effect of transparent polymer films used for packaging foods containing light‐sensitive nutrients
Authors: Korman N. , Orbey N. , Özilgen M. 
Published: April 2007

AbstractSensitive components of foods may undergo degradation reactions when subjected to light. The packaging of the food may slow down such reactions by absorbing and reflecting a fraction of the incident light. Riboflavin is a typical lightsensitive nutrient and undergoes first‐order degradation when subjected to light. Rate constants of this reaction were evaluated under 25W, 60W, 100W and 200W white light bulbs at pH = 8, at 20±1°C, with no light shielding or by shielding the light with a single fold of high density polyethylene or two folds of low density polyethylene films. Numerical values of the reaction rate constants were proportional to the light source power and varied with the number of polymer films. The proportionality constant was regarded as the ‘protection index’ of the specific film. The results implied that the smaller the protection index of the film the smaller was the degradation reaction rate constant. Although this study was done by employing two different kinds of polymer films and one light‐sensitive chemical only, this approach may be employed for comparing the packaging efficiency of polymers used for wrapping foods containing light‐sensitive components.
Electron conduction in fe‐doped polystyrene films
Authors: Sharma A. K. , Adinarayana V. , Sagar D. S. 
Published: April 2007

AbstractThe DC electrical conductivity of pure and Fe3+‐doped polystyrene films has been studied at various bias field strengths in the temperature range 304–392K. Doped films showed increased conductivity compared with undoped films up to 0.5% dopant concentration; beyond this concentration there was a decrease in the conductivity. The increase in conductivity for lower doping concentrations (0.25% and 0.5%) is attributed to the formation of charge transfer complexes. The decrease in the electrical conductivity and the increase in the activation energy at more than 0.5% dopant concentration is due to the formation of molecular aggregates. For undoped films the activation energies in the low temperature region were found to be higher than those at higher temperatures. Also, with increasing bias field strength, the activation energies showed a decrease at all temperatures studied. It is suggested, on the basis of the magnitudes of the activation energies, that electronic conduction is the dominant charge transport mechanism both at low and high temperatures.
Study of mechanical properties and morphology of interpenetrating polymer networks from castor oil based polyurethane and polystyrene
Authors: Suthar Bhikhu , Parikh Nilesh , Patel Nimish 
Published: April 2007

AbstractPolyurethane‐polystyrene sequential interpenetrating polymer networks have been synthesized from castor oil, diphenylmethane diisocyanate, styrene, ethylene glycol dimethacrylate as a crosslinker and benzoyl peroxide as an activator. The interpenetrating polymer networks were obtained as tough and transparent films by a transfer moulding technique. These IPNs were characterized by mechanical properties, viz. tensile strength, Young's modulus, elongation at break and Shore A hardness, and crosslink density. The morphological behaviour was studied by dynamic mechanical analysis and scanning electron microscopy.