bluuebunny/crossref_metadata_2025 huggingface dataset:
Optical Absorption Property and Photo‐catalytic Activity of Tin Dioxide‐doped Titanium Dioxides
Authors: LI Huai‐Xiang , XIA Rong‐Hua , JIANG Zheng‐Wei , CHEN Shan‐Shan , CHEN De‐Zhan
Published: October 2008

SnO2‐doped TiO2 films and composite oxide powders have been prepared by a sol‐gel method. Ti(OC4H9)4 and SnCl4·5H2O were used as precursors and C2H5OH was used as solvent. The optical absorption measurements indicate that the composite oxide SnO2‐TiO2 thin films exhibit smaller optical energy band gaps than pure TiO2 thin films and the optical energy band gap decreases as calcining temperature increases. X‐ray diffraction was used to characterize the phase transition for the composite oxide powders at different calcining temperatures. Aanatase phase is the main crystal structure in both pure TiO2 and Sn0.05Ti0.95O2samples if calcining temperature is below 500 °C. The rutile phase has appeared and coexisted with the anatase crystal phase for both pure TiO2 and Sn0.05Ti0.95O2 composite oxides when calcining was at 600 °C. Transmission electron microscopy analysis shows a smaller grain size in Sn0.05Ti0.95O2 powders than TiO2 powders calcined at 600 °C. When calcining temperature is 700 °C, there is only rutile phase in Sn0.05Ti0.95O2 samples, but there are still two crystal phases, anatase and rutile, coexisting in the pure TiO2 samples. Assuming the grain growth obeys the first order kinetics, Arrhenius empirical relation has been used to estimate the activation energy of 47.486 and 33.103 kJ·mol−1 for the grain growth of TiO2 and Sn0.05Ti0.95O2, respectively. The photo‐catalytic activity of the powder samples has been examined by measuring the degradation of methylene blue solution under ultra‐violet irradiation. Two effective factors of photo‐catalytic activity namely, the content of SnO2 in the TiO2 samples and the calcining temperature, have been optimized based on the photo‐catalytic degradation of methylene blue solution.
Synthesis and Characterization of Camptothecin Intercalated into Mg/Al Layered Double Hydroxide
Authors: LIU Chun‐Xia , HOU Wan‐Guo , LI Yan , LI Li‐Fang
Published: October 2008

The intercalation of camptothecin (CPT) into a layered inorganic host, Mg‐Al layered double hydroxide (LDH), was carried out using a coprecipitation method to obtain CPT‐LDH nanohybrids. It was found that the intercalated amounts (Ain) of CPT‐LDH nanohybrids were remarkably dependent on the molar ratios (RC/M) of CPT to metal ions in raw materials. The Ain value increases with the RC/M value increasing. According to the gallery heights of CPT‐LDH and sizes of CPT molecule, a probably morphology of CPT molecules in the gallery of LDH was suggested that the horizontal‐arranged monolayer and vertical‐arranged bilayer of CPT molecules coexisted in the interlayer region of LDH. An interesting result was found that the gallery height corresponding to the bilayer of CPT‐LDH sample with a high Ain value was remarkably lower than that with low Ain value. The in vitro CPT release examinations from the nanohybrids showed that the CPT‐LDH nanohybrids were a potential drug controlled release system. The kinetic analysis showed that the release kinetics of CPT from the nanohybrids obeyed the pseudo‐first order kinetic model and the diffusion of CPT through the LDH particle of CPT played an important role in controlling the drug release rate.
Metastable Equilibria for the Quaternary System Li2B4O7+Na2B4O7+K2B4O7+H2O at 15 °C
Authors: SANG Shi‐Hua , YIN Hui‐An , NI Shi‐Jun , DENG Miao
Published: October 2008

Metastable equilibrium solubilities and such physico‐chemical properties as densities, conductivity, pH, refractive index and viscosity of the solution for the quaternary system Li2B4O7+Na2B4O7+K2B4O7+H2O at 15 °C were determined experimentally. According to the experimental data, the metastable equilibrium phase diagram was plotted. In the metastable phase diagram, there are one invariant point, three univariant curves, and three fields of crystallization: Li2B2O4·16H2O, Na2B4O7·10H2O, and K2B4O7·4H2O. Potassium borate (K2B4O7·4H2O) has the smallest crystallization field and sodium borate (borax) has the biggest one. Also, the relationship diagram between the properties and the ion concentration of solution was constructed. It can be seen from the relationship diagram that the metastable equilibrium solution density values, viscosity values and refractive index values are increased apparently with the rise of lithium borate concentration, reaching the maximum values at invariant point F. Electrical conductivity values and pH values, however, fall down with the rise of ion concentration on the whole.
Synthesis, Crystal Structures and Thermal Stabilities of [Cu(bpp)2(bpdc)(H2O)2]n·2nH2O and [Cu(bpp)2]n·n (tdc) ·7.5nH2O
Authors: YU Jing‐Hua , WANG Zhong‐Ming , LUO Xin‐Ze , DU Hong‐Guang
Published: October 2008

Two novel copper(II) coordination polymers [Cu(bpp)2(bpdc)(H2O)2]n·2nH2O (1) and [Cu(bpp)2]n·n(tdc)·7.5nH2O (2) (H2bpdc=biphenyl‐4,4′‐dicarboxylic acid, bpp=1,3‐di(4‐pyridyl)propane and H2tdc=thiophene‐2,5‐dicartboxylic acid) have been synthesized by the reactions of Cu(NO3)2 and bpp with the H2bpdc or H2tdc, respectively at room temperature. In the complexes 1 and 2, their Cu atoms have a distorted octahedral geometry, and two water molecules coordinate weakly to the Cu atom in the long axial direction. Both complexes have one‐dimensional linear polymer structures. In complex 1, both carboxylate groups of the bpdc can coordinate to Cu atom, while both carboxylate groups of the tdc dianion in complex 2 do not coordinate to the Cu atom, which only balance the charge. In the both complexes, the bpp ligand has different conformation: trans‐trans in complex 1 and trans‐gauche in complex 2. The thermal gravimetric analyses indicate that both complexes are stable under 110 and 160 °C, respectively.
Facile Size‐controllable Aqueous Synthesis of Water Soluble CdTe/Cd(OH)2 Core/Shell Nanoparticles with Tunable Optical Property, High Quantum Yield and Good Stability
Authors: CAI Zhao‐Xia , CHEN Ying‐Jun , YAN Xiu‐Ping
Published: October 2008

A facile procedure was developed to prepare size‐tunable and water soluble CdTe/Cd(OH)2 core/shell nanoparticles with high quantum yields and good stability using inexpensive inorganic precursors (CdCl2 and elemental Te). The emission colors of the prepared CdTe/Cd(OH)2 core/shell nanoparticles can be readily tuned from cyan to salmon pink by varying incubation time to control the growth of the Cd(OH)2 shell onto the CdTe nanoparticles. The CdTe/Cd(OH)2 core/shell nanoparticles were characterized by transmission electron microscopy, high‐resolution transmission electron microscopy, X‐ray powder diffraction spectrometry, photoluminescence and UV‐Vis spectrometry. The good water‐soluble nature of the CdTe/Cd(OH)2 core/shell nanoparticles offers great potentiality for their bio‐labeling application. This approach is simple, mild and readily scaled up, affording a simple way for synthesis of size‐tunable inorganic metal hydroxide capped core/shell nanoparticles.
Mechanism of Molecular Recognition on Tetrapetide‐imprinted Monolith by Capillary Electrochromatography
Authors: ZHENG Chao , LIU Zhao‐Sheng , GAO Ru‐Yu , ZHANG Yu‐Kui
Published: October 2008

A tetrapeptide‐imprinted capillary monolithic column was synthesized successfully in the presence of YPLG (Tyr‐Pro‐Leu‐Gly) as template by in situ thermo‐initiated polymerization. For exploring the recognition mechanism of molecularly imprinted polymer in a capillary electrochromatography (CEC) mode, YPLG and its structural analogue, YPGL (Tyr‐Pro‐Gly‐Leu), differing in amino acid sequence, were used as model compounds. It is hard work to separate the two tetrapeptides by a simple CEC or a capillary electrophoresis mode due to their similar chemical structures and values of pI. However, the results showed that YPLG could be recognized specially by the imprinted monolith. The separation factor (α ′) and the resolution (Rs) between YPLG and YPGL were 1.73 and 3.72, respectively. The effects of organic modifier concentration, pH value of buffer, salt concentration of buffer and column temperature on the recognition of YPLG and YPGL were investigated. A non‐linear Van′t Hoff behavior of the template was observed on a YPLG‐imprinted column, which suggested the presence of multiple types of retention mechanisms or multiple types of binding sites. The results showed that the molecular recognition on MIP monolith in the CEC mode mainly derived from hydrogen bonding between YPLG and MIP and three‐dimensional structure of the imprinting cavities.
Synthesis and Structural Studies of 1‐Deoxybaccatin VI Derivatives
Authors: LIN Hai‐Xia , WANG Dian‐Long , CHEN Jian‐Min , CHEN Min‐Qin
Published: October 2008

Synthesis and crystal structures of 1‐deoxybaccatin VI derivatives, and the influence of C(9), C(10), and C(13) substituents of the tetracyclic moiety on molecular conformations were investigated. Comparison of conformations of 1‐deoxybaccatin VI derivatives reveals subtle conformational variations in the tetracyclic ring system due to deacetylation at C(10) and C(13), and 9,10‐acetonide. Additionally, C(2)‐benzoyl group exhibits an unexpected conformational flexibility in 1‐deoxybaccatin VI derivatives, which may be relevant to the bioactivity of taxanes.
Resonance Rayleigh Scattering Spectrum of Palladium(II)‐ Clindamycin‐Halofluorescein Systems and Their Analytical Applications
Authors: YI Ao‐Er , LIU Zhong‐Fang , LIU Shao‐Pu , KONG Ling
Published: October 2008

In pH 5.0–5.4 HOAc‐NaOAc buffer solution, clindamycin (Clin) could react with Pd(II) to form a 1:1 cationic chelate, which could further react with halofluorescein dyes such as diiodofluorescein (DIF), erythrosine (Ery) and eosin Y (EY) to form 1:1 ion‐association complexes. As a result, not only the absorption and fluorescence spectra were changed, but also the resonance Rayleigh scattering (RRS) intensities enhanced greatly and new RRS spectra appeared. The three reaction products had characteristic RRS spectra and their maximum RRS wavelengths were located at 285 (DIF system), 287 (Ery system) and 321 (EY system) nm, respectively. The scattering intensities were proportional to the concentration of Clin in certain range which could be applied to determine Clin. The linear ranges and detection limits of Clin were 0.025–2.1 µg·mL−1 and 7.8 ng·mL−1 for the DIF system, 0.053–2.4 µg·mL−1 and 16.0 ng·mL−1 for the Ery system, 0.038–2.4 µg·mL−1 and 11.0 ng·mL−1 for the EY system, respectively. In this work, the optimum reaction conditions and the foreign substances were investigated. A simple, sensitive and fast method was developed for the determination of Clin either in the pharmaceutical form or in the human body fluid. Moreover, the composition, structure, reaction mechanism of the ternary complexes and their effects on the absorption, fluorescence and RRS spectra as well as the reasons of RRS enhancement were discussed.
Preparation of Core‐shell Microspheres by ATRP Synthesized Macromonomer
Authors: CHU Hong , YANG Wei , CHEN Ming‐Qing , LU Jian‐Yan , SHI Dong‐Jian , AKASHI Mitusu
Published: October 2008

Poly(tert‐butyl methacrylate) macrointermediates (PtBMA‐Br) with an end of bromine atom were synthesized by atom transfer radical polymerization using ethylbromopropionate as an initiator in bulk in the presence of N,N,N′,N′′,N′′‐pentamethyl diethylenetriamine (PMDETA) as a single ligand. A new macromonomer (MAA‐ PtBMA) was successfully prepared via end‐group nucleophilic substitution with methacrylic acid to attain a high efficiency of C=C incorporation. The molecular weights of MAA‐PtBMA macromonomers were controllable from 5400 to 11000 g/mol, and the molecular weight distribution was narrow (≤1.20). Then, the PtBMA graft polystyrene (PtBMA‐g‐PSt) microspheres were prepared by dispersion copolymerization of MAA‐PtBMA macromonomers with styrene using 2,2′‐azobisisobutyronitrile as a free radical initiator in ethanol. The resulting PtBMA‐g‐PSt microspheres were regulated in diameter on a micron scale.
Reversible Addition‐fragmentation Chain Transfer Polymerization Grafted from Silicon Surface to Prepare Poly(methyl methacrylate) Brushes
Authors: YUAN Kun , LÜ Ling‐Ling , LI Zhi‐Feng , SHI Xiao‐Ning
Published: October 2008

Poly(methyl methacrylate) (PMMA) brushes grafted from silicon wafer surface were prepared using a reversible addition fragmentation chain transfer (RAFT) technique. 4‐Cyano‐4‐((thiobenzoyl)sulfanyl)pentanoic succinimide ester, a novel RAFT agent, was immobilized on the silicon wafer surface. RAFT polymerizations were then conducted from the silicon surface to polymerize from the silicon surface. Kinetic studies revealed that the thickness of the PMMA film increased almost linearly with the polymerization time after 2 h, indicating that the chain growth from the surface was a controlled process with a "living" character. The PMMA brushes were characterized using ellipsometry, X‐ray photoelectron spectra (XPS), atomic force microscopy (AFM) and contact angle measurements.
Enhanced Energy Conversion Efficiency of La3+‐Modified Nanoporous TiO2 Electrode Sensitized with a Ruthenium Complex
Authors: WU Xiao‐Hong , WANG Song , GUO Yun , XIE Zhao‐Yang , HAN Lu , JIANG Zhao‐Hua
Published: October 2008

The nature of TiO2 films and sensitizer play significant roles in determining the overall efficiency and mechanical stability of dye sensitized solar cell. In this study, cis‐RuL2(SCN)2, (L=2,2′‐dipyridine‐4,4′‐dicarboxlic acid) was synthesized from 4‐methylpyridine by the procedure of cross‐coupling, oxidation, conjugation and ligand substitution. TiO2 films were obtained by blending P25 and TiO2 sol. To increase the photoelectric properties of the thin TiO2 films, La(NO3)3 with different concentrations (0.1%, 0.3%, 0.5% and 0.7%) were added into the sol. Both undoped and doped samples of the thin films were sensitized by cis‐RuL2(SCN)2 and structurally characterized by X‐ray diffraction, atomic force microscopy and X‐ray photoelectron spectroscopy. In addition, the photoelectric properties of the TiO2 electrodes were investigated. The results show that doping lanthanum ions made the grain size smaller and surface area larger. When the concentration dopant is 0.5%, the short circuit current and open circuit voltage of the TiO2 film reach maximum. The short circuit current increases 0.54 mA/cm2 more than that of undoped film, and the open‐circuit voltage increases 30.41 mV more than that of undoped film.
Synthesis and Triethylamine‐catalyzed Cyclization Reaction of 4‐Pentyne‐1,3‐dione System Having Various Substituents
Authors: KURODA Hirofumi , IZAWA Hironori
Published: October 2008

4‐Pentyne‐1,3‐dione system having various substituents was synthesized in two steps and the cyclization behavior of the obtained 1,3‐dicarbonyl compounds was examined. γ‐Pyrones and 2‐alkylidene‐2,3‐dihydro‐3‐furanones were obtained by the triethylamine‐catalyzed cyclization of the 4‐pentyne‐1,3‐dione system having a diketone moiety. Furthermore, a phenol derivative was obtained in the case of 4‐pentyne‐1,3‐dione system having an ester moiety. Thus, it was found that the kind of substituents in the 4‐pentyne‐1,3‐dione system remarkably influenced the selectivity in the cyclization.
Rates and predictors of chemotherapy use for stage III colon cancer
Authors: Etzioni David A. , El‐Khoueiry Anthony B. , Beart Robert W.
Published: October 2008

Despite consensus regarding the benefits of chemotherapy for stage III colon cancer, multiple reports have found significant variations in rates of use. In the current study, the authors attempted to systematically review reports of the community rates at which chemotherapy is administered for stage III colon cancer in the US, and in so doing plan strategies for improving rates of use. A systematic search strategy was undertaken using MEDLINE, Web of Science, and bibliographies to find reports of the rates at which patients with stage III colon cancer receive chemotherapy. A total of 22 studies published since 1990 were identified, with rates of chemotherapy use ranging from 39% to 71%. Age and comorbidity were found to be the most significant patient factors, but studies also found racial/ethnic and socioeconomic disparities in the rates of chemotherapy. Patients treated at teaching hospitals did not clearly receive chemotherapy more often. Oncologists and surgeons who treat a higher volume of colorectal cancer patients were more likely to have chemotherapy initiated in their patients. The authors developed a conceptual model of the process pathway experienced by patients with stage III colon cancer to demonstrate areas of potential underuse of chemotherapy. Nearly half of patients with stage III chemotherapy in the US do not receive chemotherapy. Although many patients are too old or frail to benefit appropriately, for many patients chemotherapy is simply not initiated. Attention needs to be focused on systematic approaches to prevent systems failures that result in underuse. Guidelines regarding chemotherapy use in elderly patients are especially important. Cancer 2008. © 2008 American Cancer Society.
National Cancer Institute Patient Navigation Research Program
Authors: Freund Karen M. , Battaglia Tracy A. , Calhoun Elizabeth , Dudley Donald J. , Fiscella Kevin , Paskett Electra , Raich Peter C. , Roetzheim Richard G. ,   The Patient Navigation Research Program Group
Published: October 2008

BACKGROUND.

Patient, provider, and systems barriers contribute to delays in cancer care, a lower quality of care, and poorer outcomes in vulnerable populations, including low‐income, underinsured, and racial/ethnic minority populations. Patient navigation is emerging as an intervention to address this problem, but navigation requires a clear definition and a rigorous testing of its effectiveness. Pilot programs have provided some evidence of benefit, but have been limited by evaluation of single‐site interventions and varying definitions of navigation. To overcome these limitations, a 9‐site National Cancer Institute Patient Navigation Research Program (PNRP) was initiated.

METHODS.

The PNRP is charged with designing, implementing, and evaluating a generalizable patient navigation program targeting vulnerable populations. Through a formal committee structure, the PNRP has developed a definition of patient navigation and metrics to assess the process and outcomes of patient navigation in diverse settings, compared with concurrent continuous control groups.

RESULTS.

The PNRP defines patient navigation as support and guidance offered to vulnerable persons with abnormal cancer screening or a cancer diagnosis, with the goal of overcoming barriers to timely, quality care. Primary outcomes of the PNRP are 1) time to diagnostic resolution; 2) time to initiation of cancer treatment; 3) patient satisfaction with care; and 4) cost effectiveness, for breast, cervical, colon/rectum, and/or prostate cancer.

CONCLUSIONS.

The metrics to assess the processes and outcomes of patient navigation have been developed for the NCI‐sponsored PNRP. If the metrics are found to be valid and reliable, they may prove useful to other investigators. Cancer 2008. © 2008 American Cancer Society.
Marital quality and survivorship
Authors: Yang Hae‐Chung , Schuler Tammy A.
Published: October 2008

BACKGROUD:

Although marital distress has been implicated in difficulties with adjustment to a breast cancer diagnosis, its long‐term effects, especially on physical recovery, are unknown.

METHODS:

Longitudinal data from newly diagnosed breast cancer patients (N = 100) who were married or cohabiting were used. Patients were assessed after diagnosis and surgery (baseline) and then reassessed every 4 or 6 months for the next 5 years. Women in stable, distressed relationships (n = 28) were compared with those in stable, nondistressed relationships (n = 72). Stress, health behavior, and health outcomes were examined using mixed‐effects modeling.

RESULTS:

Overall, marital distress was associated with slowed recovery trajectories and poor outcomes. At baseline, both groups had equivalent, high levels of stress, but diverged thereafter. Stress declined more slowly for the Distressed group, and by 5 years it remained significantly higher. Differential reductions in physical activity were also observed. With regard to health, the Distressed group was found to have a slower recovery in performance status and more symptoms/signs of illness and treatment side effects through 3 years. Finally, all the effects were observed above and beyond reductions occurring with depressive symptomatology, which was significantly higher in the Distressed group.

CONCLUSIONS:

Marital distress is not only associated with worse psychologic outcomes for breast cancer survivors, but poorer health and a steeper decline in physical activity. These novel data demonstrate recovery trajectories for breast cancer survivors to be constrained for those also coping with ongoing difficulties in their marriage. Cancer 2009. © 2008 American Cancer Society.
Maintenance factors for persistence of bulimic pathology: A prospective natural history study
Authors: Bohon Cara , Stice Eric , Burton Emily
Published: October 2008

Objective:

To characterize the natural course of bulimia nervosa and identify potential maintenance factors that predict persistence of bulimic pathology in order to advance knowledge of processes that perpetuate this eating disturbance and permit the design of more efficacious treatments.

Method:

We followed 96 women with threshold or subthreshold bulimia nervosa over a 1‐year period with quarterly interviews.

Results:

There were high rates of remission and relapse on a month‐to‐month basis, but remission became more likely to persist after a period of approximately 4 months of symptom abstinence. Initial elevations in thin‐ideal internalization, expectations for reward from eating, and binge frequency predicted greater time to remission of binge eating. Initial elevations in dietary restraint and compensatory behavior frequency predicted greater time to remission of compensatory behaviors.

Discussion:

Results imply that treatments for eating disorder may be more effective if they can reduce thin‐ideal internalization, eating expectancies, and ineffective dieting and produce rapid cessation of binge eating and compensatory behaviors. © 2008 by Wiley Periodicals, Inc. Int J Eat Disord 2009
Affective lability and impulsivity in a clinical sample of women with bulimia nervosa: The role of affect in severely dysregulated behavior
Authors: Anestis Michael D. , Peterson Carol B. , Bardone‐Cone Anna M. , Klein Marjorie H. , Mitchell James E. , Crosby Ross D. , Wonderlich Stephen A. , Crow Scott J. , le Grange Daniel , Joiner Thomas E.
Published: October 2008

Objective:

The primary aim of this study was to examine the role of affective lability in maladaptive behaviors in a sample of women who meet DSM criteria for current bulimia nervosa (BN).

Method:

Participants were administered a semistructured diagnostic interview (SCID‐P) and only those who currently met criteria for BN (N = 134) were included in the analyses. All other data were collected through the use of self‐report questionnaires.

Results:

Affective lability significantly predicted the Impulsive Behavior Scale score (sr = 0.21, t = 2.64, p < .009, f2 = 0.06) and excessive reassurance seeking (sr = 0.21, t = 2.74, p < .007, f2 = 0.06), even when controlling for age, depressive symptoms, state and trait anxiety, and general impulsivity.

Discussion:

The degree to which individuals with BN experience labile emotions is associated with several indicators of dysregulated behavior such that higher levels of affective lability predict a more severely dysregulated behavioral profile. © 2008 by Wiley Periodicals, Inc. Int J Eat Disord 2009
Preparation, Electrochemistry, and Electrocatalytic Activity of Lead Pentacyanonitrosylferrate Film Immobilized on Carbon Ceramic Electrode
Authors: Razmi H. , Heidari H.
Published: October 2008

Lead pentacyanonitrosylferrate (PbPCNF), a new Prussian blue analog, was immobilized on the surface of a carbon ceramic electrode (CCE) prepared by sol‐gel method. The immobilization process consists of adding a certain amount of metallic lead to the electrode matrix before gelation, and chemical derivatization of Pb on the electrode surface to a PbPCNF solid film by immersing the electrode in a solution of sodium pentacyanonitrosylferrate (PCNF). The composition of the synthesized PbPCNF was characterized by FTIR, scanning electron microscopy (SEM), and energy‐dispersive X‐ray (EDX) techniques. The resulting modified electrode showed electroactivity at two redox centers. The electrochemical behavior of the PbPCNF modified carbon ceramic electrode (PbPCNF|CCE) was studied by cyclic voltammetry. Under optimized conditions the peak‐to‐peak separation is only 39 mV, indicative of a surface reaction. Ion effects of the supporting electrolyte suggest that cations have a considerable effect on the electrochemical behavior of the modified electrode. The transfer coefficient (α) and the charge transfer rate constant at the modifying film|electrode interface (ks) were calculated. The electrocatalytic activity of the modified electrode toward the electro‐reduction of peroxodisulfate was studied in details.
Aptasensor for Thrombin Based on Carbon Nanotubes‐Methylene Blue Composites
Authors: Evtugyn Gennady , Porfireva Anna , Ryabova Maria , Hianik Tibor
Published: October 2008

The amperometric and EQCM aptasensors based on DNA aptamers immobilized by avidin‐biotin method or by electrostatic adsorption onto multiwalled carbon nanotube layer contained methylene blue (MB) have been developed and examined for thrombin detection in buffer and in spiked blood serum. The presence of MB increases the binding capacity of the surface layer and enhances the range of thrombin concentrations to be determined. This results in significant improvement of analytical characteristics of thrombin detection. The EQCM aptasensors allowed us to detect 0.3–100 nM and amperometric aptasensors 10–1000 nM of thrombin.
Using college board data to examine trends in New Hampshire's college‐bound students
Authors: Toutkoushian Robert K.
Published: October 2008

System‐level institutional research offices can provide administrators and policymakers with important analysis in support of their mission.
Confronting ambiguity, anarchy, and crisis in institutional research: Using student unit record databases in extra‐institutional research
Authors: Musoba Glenda D. , Gross Jacob P. K. , Hossler Don
Published: October 2008

This chapter explores how an institution‐affiliated but grant‐funded independent research office developed a statewide student record database for institutional research studies.
Annual miles drive used car prices
Authors: Engers Maxim , Hartmann Monica , Stern Steven
Published: October 2008

This paper investigates whether the net benefits from owning a vehicle, proxied by annual miles driven, explain the price declines observed over a vehicle's life. We first model the household decision on how much to drive each of its vehicles. Then we empirically establish that variation in household annual miles across brands explains observed price declines. Furthermore, the effect of vehicle age on annual miles decisions (and consequently on market value) depends on household characteristics and the composition of the vehicle stock owned. Copyright © 2008 John Wiley & Sons, Ltd.
Batch cooling crystallization of xylitol produced by biotechnological route
Authors: Martínez Ernesto Acosta , Giulietti Marco , Almeida e Silva João Batista de , Derenzo Silas , Almeida Felipe Maria das Graças
Published: October 2008

BACKGROUND: This work deals with the xylitol production by biotechnological routes emphasizing the purification process using crystallization.

RESULTS: Xylitol volumetric productivity of 0.665 g L−1 h−1 and yield of 0.7024 g g−1 were obtained after 92 h fermentation. The fermented broth (61.3 g L−1 xylitol) was centrifuged, treated and concentrated obtain a syrup (745.3 g L−1 xylitol) which was crystallized twice, xylitol crystals with 98.5–99.2% purity being obtained.

CONCLUSION: The hypothetical distribution obtained permits the determination of modeling parameters, which make possible the estimation of crystal dominant size from different initial experimental conditions. Copyright © 2008 Society of Chemical Industry
Expression of brain‐type fatty acid‐binding protein (fabp7) in medaka during development
Authors: Maruyama Kouichi , Kojima Ayako , Yasuda Takako , Suetomi Katsutoshi , Kubota Yoshihisa , Takahashi Sentaro , Ishikawa Yuji , Fujimori Akira
Published: October 2008

Fatty acid‐binding proteins (FABPs) belong to a multigene family of small intracellular proteins that bind hydrophobic ligands. Recent studies have indicated that FABP7 plays important roles in neurogenesis or neuronal migration in vertebrates. In this study, we isolated cDNA and the genomic fragment containing the fabp7 gene for medaka fish and examined the expression of the medaka fabp7 gene through the development of their central nervous system (CNS). The medaka fabp7 gene consists of four exons in approximately 1 kb of the genomic region. Its deduced amino acid sequence exhibits over 80% identity with those of other higher vertebrates. In situ hybridization analysis demonstrated that fabp7‐positive cells first appear at stage 22 in a small dorsal domain of the retina, dorsal diencephalon, and rhombencephalon, then expand to the entire CNS including the retina and the spinal cord. In addition, we generated two lines of transgenic medaka with 1.7 kb upstream of the fabp7 gene combined with the enhanced‐green fluorescence protein (EGFP) gene. The spatio‐temporal expression patterns of EGFP in these animals were consistent with the results of in situ hybridization analysis. The result of our reporter assays with a series of truncated fabp7 promoters suggested that POU elements play a role in fabp7 expression in medaka as well as in other vertebrates. Our transgenic animal will contribute to clarifying the role of FABP7 in the development of CNS. J. Exp. Zool. (Mol. Dev. Evol.) 310B:577–587, 2008. © 2008 Wiley‐Liss, Inc.
Implementation of a physician assistant/hospitalist service in an academic medical center: Impact on efficiency and patient outcomes
Authors: Roy Christopher L. , Liang Catherine L. , Lund Maha , Boyd Catherine , Katz Joel T. , McKean Sylvia , Schnipper Jeffrey L.
Published: October 2008

BACKGROUND:

Accreditation Council on Graduate Medical Education (ACGME) duty hour restrictions have led to the widespread implementation of non–house staff services in academic medical centers, yet little is known about the quality and efficiency of patient care on such services.

OBJECTIVE:

To evaluate the quality and efficiency of patient care on a physician assistant/hospitalist service compared with that of traditional house staff services.

DESIGN:

Retrospective cohort study.

SETTING:

Inpatient general medicine service of a 747‐bed academic medical center.

PATIENTS:

A total of 5194 consecutive patients admitted to the general medical service from July 2005 to June 2006, including 992 patients on the physician assistant/hospitalist service and 4202 patients on a traditional house staff service.

INTERVENTION:

A geographically localized service staffed with physician assistants and supervised by hospitalists.

MEASUREMENTS:

Length of stay (LOS), cost of care, inpatient mortality, intensive care unit (ICU) transfers, readmissions, and patient satisfaction.

RESULTS:

Patients admitted to the study service were younger, had lower comorbidity scores, and were more likely to be admitted at night. After adjustment for these and other factors, and for clustering by attending physician, total cost of care was marginally lower on the study service (adjusted costs 3.9% lower; 95% confidence interval [CI] −7.5% to −0.3%), but LOS was not significantly different (adjusted LOS 5.0% higher; 95% CI, −0.4% to +10%) as compared with house staff services. No difference was seen in inpatient mortality, ICU transfers, readmissions, or patient satisfaction.

CONCLUSIONS:

For general medicine inpatients admitted to an academic medical center, a service staffed by hospitalists and physician assistants can provide a safe alternative to house staff services, with comparable efficiency. Journal of Hospital Medicine 2008;3:361–368. © 2008 Society of Hospital Medicine.
Discharge against medical advice: Ethical considerations and professional obligations
Authors: Berger Jeffrey T.
Published: October 2008

Discharges against medical advice (AMA) account for approximately 1% of discharges for general medical patients. Patients discharged AMA have longer eventual hospital stays and worse health outcomes. These patients are also less likely to have an established relationship with a physician, tend to have poorer social supports, and are more likely to abuse alcohol and other substances. These discharges are also distressing for physicians and other health professionals. How should physicians manage their conflicted obligations to respect patients' choices and to prevent harms from befalling their patients? What are physicians' obligations to their patients who leave accepting only partial or inadequate treatment plans or no treatment at all? When should physicians question the decision‐making capacity of patients who make dangerous judgments to leave the hospital? This article examines the ethical and professional implications of discharge AMA. Journal of Hospital Medicine 2008;3:403–408. © 2008 Society of Hospital Medicine.
Survey of the year 2007 commercial optical biosensor literature
Authors: Rich Rebecca L. , Myszka David G.
Published: October 2008

In 2007, 1179 papers were published that involved the application of optical biosensors. Reported developments in instrument hardware, assay design, and immobilization chemistry continue to improve the technology's throughput, sensitivity, and utility. Compared to recent years, the widest range of platforms, both traditional format and array‐based, were used. However, as in the past, we found a disappointingly low percentage of well‐executed experiments and thoughtful data interpretation. We are alarmed by the high frequency of suboptimal data and over‐interpreted results in the literature. Fortunately, learning to visually recognize good—and more importantly, bad—data is easy. Using examples from the literature, we outline several features of biosensor responses that indicate experimental artifacts versus actual binding events. Our goal is to have everyone, from benchtop scientists to project managers and manuscript reviewers, become astute judges of biosensor results using nothing more than their eyes. Copyright © 2008 John Wiley & Sons, Ltd.
Spatially patterned gene expression for guided neurite extension
Authors: Houchin‐Ray Tiffany , Huang Alyssa , West Erin R. , Zelivyanskaya Marina , Shea Lonnie D.
Published: October 2008

Axon pathfinding by localized expression of guidance molecules is critical for the proper development of the nervous system. In this report, we present a well‐defined spatially patterned gene expression system to investigate neurite guidance in vitro. Nonviral gene delivery was patterned by combining substrate‐mediated gene delivery with soft lithography techniques, and the amount of protein produced at the region of localized expression was varied by altering the vector concentration and the width of the pattern, highlighting the flexibility of the system. A neuronal coculture model was used to investigate responses to spatial patterns of nerve growth factor (NGF) expression. The soluble NGF gradient elicited a guidance cue, and the degree of guidance was governed by the distance a neuron was cultured from the pattern and the time between accessory cell and neuron seedings. A portion of the diffusible NGF bound to the culture surface in the extracellular space, and the surface‐associated NGF supported neuron survival and neurite outgrowth. However, the surface‐bound NGF gradient alone did not elicit a guidance signal, and in fact masked the guidance cue by soluble NGF gradients. Mathematical modeling of NGF diffusion was used to predict the concentration gradients, and both the absolute and fractional gradients capable of guiding neurites produced by patterned gene expression differed substantially from the values obtained with existing engineered protein gradients. Spatially patterned gene expression provides a versatile tool to investigate the factors that may promote neurite guidance. © 2008 Wiley‐Liss, Inc.
Histone deacetylase activity in conjunction with E2F‐1 and p53 regulates Apaf‐1 expression in 661W cells and the retina
Authors: Wallace Deborah M. , Cotter Thomas G.
Published: October 2008

Apaf‐1 and the cysteine proteases known as caspases are genes central to the intrinsic apoptotic pathway in the retina. Previously, we have shown that histone deacetylase (HDAC) activity regulates Apaf‐1 expression in the retina. In this study, we unravel the detailed molecular mechanism of HDAC‐mediated regulation of Apaf‐1 initially by use of a cell line (661W), which expresses some cone‐specific genes and then by means of an ex vivo retinal explant system. Inhibition of HDAC activity by trichostatin A (TSA) up‐regulates Apaf‐1 expression, which precedes the induction of apoptosis. Furthermore, by a bioinformatics approach, we identify E2F‐1 and p53 binding sites on the mouse Apaf‐1 promoter and show by chromatin immunoprecipitation assays that these sites are occupied in vitro and that treatment with TSA results in increased binding of E2F‐1 and p53 to the Apaf‐1 promoter. By performing siRNA to these transcription factors, we illustrate that they govern Apaf‐1 expression levels in vitro. Finally, in a retinal explant system, we show that similar to our 661W results, E2F‐1 and p53 are up‐regulated after inhibition of HDAC activity in the retina. This correlates with our previous observation in the explant system that Apaf‐1 expression increases significantly and leads to an induction of apoptosis after inhibition of HDAC activity. Overall, we propose a role for HDAC activity, E2F‐1, and p53 in the regulation of Apaf‐1 expression in 661W cells; initial data also indicate a regulatory role in the retina. © 2008 Wiley‐Liss, Inc.
Immunocytochemical expression of dopamine‐related transcription factors Pitx3 and Nurr1 in prenatally stressed adult rats
Authors: Katunar Maria R. , Saez Trinidad , Brusco Alicia , Antonelli Marta C.
Published: October 2008

Rats exposed to different types of stress during the last week of pregnancy produce offspring that show severe anomalies in neural development and brain morphology. We have previously reported that prenatal stress (PS) induced by immobilization increases D2‐type dopamine (DA) receptor levels in the adult offspring, with a concomitant reduction in DA release in prefrontal cortex after amphetamine stimulation. Recently, two transcription factors, Nurr1 and Pitx3, have been identified that are expressed at critical moments of DA neuron differentiation. Their genetic expression is activated immediately after these neuron determinations and maintained through adult life. Nurr1 regulates several proteins that are required for dopamine synthesis and regulation, and Pitx3 is specifically involved in the terminal differentiation and maintenance of dopamine neurons. By means of an immunocytochemistry approach, we studied the expression of Nurr1 and found an ubiquitous distribution in cerebral cortex, hippocampus, thalamus, amygdala, and midbrain, whereas Pitx3 remains restricted to the mesencephalic DA neurons such as substantia nigra and ventral tegmental area. Our results show that the expression of both Nurr1 and Pitx3 increased in prenatally stressed adult offspring in the ventral tegmental area, whereas no changes were observed in the substantia nigra area. It might be hypothesized that the increase of the specific dopaminergic transcription factors might be a compensatory mechanism to counteract the reduction in dopamine levels previously observed as a consequence of prenatal stress. © 2008 Wiley‐Liss, Inc.
Innate and adaptive immune activation in the brain of MPS IIIB mouse model
Authors: DiRosario Julianne , Divers Erin , Wang Chuansong , Etter Jonathan , Charrier Alyssa , Jukkola Peter , Auer Herbert , Best Victoria , Newsom David L. , McCarty Douglas M. , Fu Haiyan
Published: October 2008

Mucopolysaccharidosis (MPS) IIIB is a lysosomal storage disease with severe neurological manifestations due to α‐N‐acetylglucosaminidase (NaGlu) deficiency. The mechanism of neuropathology in MPS IIIB is unclear. This study investigates the role of immune responses in neurological disease of MPS IIIB in mice. By means of gene expression microarrays and real‐time quantitative reverse transcriptase–polymerase chain reaction, we demonstrated significant up‐regulation of numerous immune‐related genes in MPS IIIB mouse brain involving a broad range of immune cells and molecules, including T cells, B cells, microglia/macrophages, complement, major histocompatibility complex class I, immunoglobulin, Toll‐like receptors, and molecules essential for antigen presentation. The significantly enlarged spleen and lymph nodes in MPS IIIB mice were due to an increase in splenocytes/lymphocytes, and functional assays indicated that the T cells were activated. An autoimmune component to the disease was further suggested by the presence of putative autoantigen or autoantigens in brain extracts that reacted specifically with serum IgG from MPS IIIB mice. We also demonstrated for the first time that immunosuppression with prednisolone alone can significantly slow the central nervous system disease progression. Our data indicate that immune responses contribute greatly to the neuropathology of MPS IIIB and should be considered as an adjunct treatment in future therapeutic developments for optimal therapeutic effect. © 2008 Wiley‐Liss, Inc.
Spinal cord dysmyelination caused by an antiproteolipid protein IgM antibody: Implications for the mechanism of central nervous system myelin formation
Authors: Rosenbluth J. , Schiff R.
Published: October 2008

Antiglycolipid IgM antibodies are known to induce formation of “wide spaced” or “expanded” myelin, a distinctive form of dysmyelination characterized by a repeat period approximately two or three times normal, which is seen also in diseases, including multiple sclerosis. To determine whether an antibody directed against a myelin protein would cause equivalent pathology, we implanted O10 hybridoma cells into the spinal cord of adult or juvenile rats. O10 produces an IgM directed against PLP, the major protein of CNS myelin. Subsequent examination of the cords showed focal demyelination and remyelination. In addition, however, some juvenile cords, but none of the adult cords, displayed wide‐spaced myelin with lamellae separated by an extracellular material comprising elements consistent with IgM molecules in appearance. Wide spacing tended to involve the outer layers of the sheath and in some cases alternated with normally spaced lamellae. A feature not seen previously consists of multiple expanded myelin lamellae in one sector of a sheath continuous with normally spaced lamellae in another, resulting in variation in sheath thickness around the axonal circumference. This uneven distribution of wide‐spaced lamellae is most simply explained based on incorporation of IgM molecules into immature sheaths during myelin formation and implies a model of CNS myelinogenesis more complex than simple spiraling. The periaxonal space never displays widening of this kind, but the interface with adjacent myelin sheaths or oligodendrocytes may. Thus, wide spacing appears to require that IgM molecules bridge between two PLP‐containing membranes and does not reflect the mere presence of immunoglobulin within the extracellular space. © 2008 Wiley‐Liss, Inc.
AMPA receptor‐mediated cell death is reduced by docosahexaenoic acid but not by eicosapentaenoic acid in area CA1 of hippocampal slice cultures
Authors: Ménard Caroline , Patenaude Christian , Gagné Anne‐Marie , Massicotte Guy
Published: October 2008

Over the last decade, several studies have shown that high levels of polyunsaturated fatty acids (PUFAs) in the brain might limit neuronal damage in various pathological conditions. For example, in animal models of Alzheimer's disease, omega‐3 type PUFAs such as docosahexaenoic (DHA) and eicosapentaenoic (EPA) acids have been proposed to decrease both the cognitive and the cellular manifestations of premature ageing. The mechanisms by which they promote brain integrity remain to be established, and the experiments on cultured hippocampal slices described here examine the possibility that omega‐3 fatty acids can modulate brain cell viability by interacting with glutamate receptors. We observed, by lactate dehydrogenase release and propidium iodide (PI) uptake, that excitotoxicity triggered by an alpha‐amino‐3‐hydroxy‐5‐methyl‐4‐isoxazole propionic acid (AMPA) receptor agonist was markedly reduced in hippocampal slices treated with DHA. PI uptake experiments also revealed that neuroprotection by DHA was restricted to the hippocampal CA1 region and could not be reproduced by EPA or arachidonic acid, an omega‐6 PUFA. Moreover, the beneficial effect of DHA was specific to AMPA receptor stimulation, insofar as the toxicity induced by N‐methyl‐D‐aspartate or kainate receptor agonists was not diminished by DHA preincubation. Biotinylation experiments finally indicated that the neuroprotective actions of DHA could result from down‐regulation of AMPA receptors in hippocampal membranes. This investigation thus provides the first indication that a beneficial outcome of DHA on the brain could derive from specific modulation of AMPA‐mediated toxicity, reinforcing the notion that dietary DHA uptake might be useful in preventing neurodegenerative diseases. © 2008 Wiley‐Liss, Inc.
Cyclophilin D is expressed predominantly in mitochondria of γ‐aminobutyric acidergic interneurons
Authors: Hazelton Julie L. , Petrasheuskaya Maryna , Fiskum Gary , Kristián Tibor
Published: October 2008

Brain mitochondria are relatively resistant to calcium‐induced mitochondrial permeability transition (MPT), with heterogenic response to the insult. The cause for this heterogeneity is not clear, so we studied the distribution of a key regulator of the MPT, cyclophilin D (cypD), within the rat brain by using immunohistology and Western blotting. Motor and parietal cortex, hippocampus, striatum, substantia nigra, ventral tegmental area, septum, and mammillary nucleus displayed a strong immunoreactivity to cypD within specific subpopulation of neurons. The staining was punctate and intense, particularly in perinuclear regions of cells. Apart from neurons, a subpopulation of astrocytes and NG2‐positive cells showed higher cypD immunoreactivity. Double staining of cypD with cytochrome oxidase confirmed the mitochondrial specificity of cypD immunoreactivity. The neurons with high levels of cypD also expressed glutamate decarboxylase (GAD) and the calcium binding protein parvalbumin or calbinding D‐28k, identifying these cells as interneurons. Western blots confirmed our immunohistochemical findings, showing significantly higher levels of cypD in crude mitochondria of substantia nigra compared with cortex or striatum. Furthermore, nonsynaptic mitochondria representing mainly mitochondria from cell bodies of neurons and glia have about 16% higher levels of cypD compared with synaptic mitochondria that are localized in presynaptic buttons. These data suggest that the underlying factor of heterogenic response of isolated brain mitochondria to MPT‐inducing insults can be the different expression levels of cypD, with mitochondria originated from interneurons as the most sensitive. © 2008 Wiley‐Liss, Inc.