bluuebunny/crossref_metadata_2025 huggingface dataset:
What do physicians in practice do to prevent osteoporosis?
Authors: Dr. Grisso Jeane Ann , Baum Carl R. , Turner Barbara J.
Published: March 2010

Osteoporosis-associated fractures are a major public health problem in the United States. Although clinicians and policy groups have advocated estrogen replacement therapy and other clinical measures to prevent osteoporosis, few studies have assessed whether these measures are being adopted by physicians in practice. The purpose of this study is to evaluate physicians' use of osteoporosis prevention measures and to assess the impact of physician specialty and practice setting on osteoporosis prevention performance.

A survey of nearly 300 physicians was carried out in a large metropolitan area. Gynecologists, general internists, and cardiopulmonary specialists were included from one of three practice settings: fee-for-service private practice, full-time academic medicine, or a large health maintenance organization.

Most physicians, regardless of clinical specialty or practice setting, report that they advocate exercise and calcium supplementation. Few physicians prescribe estrogen replacement therapy (ERT) for the majority of their postmenopausal patients. Although there are minimal differences among the three types of practice settings examined, ERT varies markedly by clinical specialty. Of the gynecologists surveyed, 37% report prescribing ERT for the majority of their postmenopausal patients to prevent osteoporosis compared to only 7 and 5% of general internists and cardiopulmonary specialists, respectively (χ2 = 45.3, p < 0.0001).

Although the efficacy of exercise and calcium supplementation to prevent osteoporotic fractures has not been well established, these measures are commonly advocated by both generalists and subspecialists. Although gynecologists are significantly more likely to prescribe ERT to prevent osteoporosis than the other clinical specialists, in general very few physicians prescribe ERT for most postmenopausal patients. This is despite the documented benefit of ERT in preventing osteoporotic fractures. Reasons are explored for physician reluctance to prescribe ERT.
An automatic method for bone histomorphometry: Assessment with reference to usual static and dynamic parameters
Authors: Dr. Juvin Robert , Phelip Xavier , Camus Emmanuel , Usson Yves
Published: March 2010

To perform a fast and reproducible analysis in bone histomorphometry, we developed an automatic method for calculating static and dynamic parameters.

A color automatic image analyzer (SAMBA 200) was used to obtain the usual parameters of bone histomorphometry: bone volume (Cn-BV%TV), osteoid volume (Cn-OV%BV), and osteoid surface (Cn-OS%BS). A specialized algorithm was designed for calculation of the mineral apposition rate (MAR). Eroded surface (Cn-ES%BS) was read in a semiautomatic mode using a cursor.

To validate this program, we input 30 samples from patients with bone disease (20 osteoporosis, 6 renal osteodystrophy, 2 osteomalacia, and 2 hyperparathyroidism) using manual and automatic modes.

The results obtained showed a highly significant correlation with the usual manual method for all parameters: OS/BS, r = 0.93; OV/BV, r = 0.98; MAR, r = 0.90. With the automatic method, larger values were found for osteoid parameters and MAR and lower values for BV/TV. There were no statistical differences for OV/BV and MAR when compared to the reference manual method.

This study establishes that automatic measurements of osteoid parameters and MAR can be performed by a fast analyzer with as good reproducibility and accuracy as the manual method.
Exercise patterns and trabecular bone density in college women
Authors: Davee Anne M. , Rosen Clifford J. , Adler Robert A.
Published: March 2010

To assess the effects of physical activity patterns on trabecular bone density in college women, we studied three groups of nonsmoking eumenorrheic women with different (but chronic) exercise regimens. There were nine sedentary (SED) women exercising less than 1 h/week, nine women who performed aerobic (AER) exercise greater than 2.5 h/week, and nine women who supplemented aerobics with muscle-building activities (MB) for more than 1 h/week. Resting energy expenditure, calorie, protein, and calcium intake, total body weight, and body mass index were not statistically different among the three groups. AER and SED women had similar lumbar bone mineral density (BMD). MB women had significantly greater spinal bone density (p < 0.007 versus SED, AER). IGF-1 (insulin-like growth factor) concentrations were greatest in MB (p < 0.01), and hours muscle building per week correlated with IGF-1 (r = 0.86, p < 0.03). For all 27 women (mean age 24.5 years), body mass index was the single best predictor of lumbar BMD (r = 0.42, p < 0.03); hours in muscle-building exercise per week conferred an additive effect on lumbar BMD.

This cross-sectional study of young women suggests chronic muscle-building exercises may augment lumbar bone mass. The additive effect of anaerobic exercise on bone density may be mediated by both local weight-bearing changes and possible systemic factors.
Zinc excretion in osteoporotic women
Authors: Professor Herzberg Mala , Foldes J. , Steinberg R. , Menczel J.
Published: March 2010

The relation of zinc to the aging skeleton was investigated in 140 women aged 36–85 years, mostly postmenopausal, who attended the Jerusalem Osteoporosis Center.

Osteoporosis was determined by lumbar spine radiograms (Smith index). Bone density (BD) of the distal radius was assessed by Compton spectroscopy and bone mineral content (BMC) at the same site by single-photon absorptiometry. Urine samples (24 h) were analyzed for zinc (UZn), hydroxyproline (UHP), calcium (UCa), magnesium (UMg), and phosphorus (UP) and expressed per gram creatinine.

Patients with definite osteoporosis (n = 94) compared to subjects with borderline or no osteoporosis (n = 34) had a significantly higher mean age (67.4 versus 58.6 years), postmenopausal age (PMA, 19.9 versus 11.0), UZn (811 versus 581), UHP (23.5 versus 18.2), and UMg (90.4 versus 74.3). Urinary calcium UCa and phosphorus UP were similar in both groups. The bone mass measurements BD, BMC, and CI were lower in the osteoporotic group. Hyperzincuria (UZn above 800 μg/g creatinine) was found in 41 osteoporotic patients (45%) compared to 6 subjects in the control group (17%). In view of the positive correlation between UZn and age (r = 0.35, p = 0.001) and to eliminate the effect of age, a separate analysis was performed for 66 subjects under the age of 65 in whom the mean age was similar for the osteoporosis patients (n = 38) and control group (n = 28). Nevertheless, the osteoporosis patients still had a significantly higher mean UZn and UHP.

A woman who does not suffer from any acute or metabolic disease, with urinary zinc of 800 μg/g creatinine, had about a 90% chance of having definite osteoporosis. UZn correlated with UHP and thus the increased UZn may reflect an increased rate of bone resorption.
Bone changes occurring early after cessation of ovarian function in beagle dogs: A histomorphometric study employing sequential biopsies
Authors: Faugere Marie-Claude , Friedler Robert M. , Fanti Paolo , Malluche Hartmut H.
Published: March 2010

The beagle dog model has been established by our laboratory as a useful animal model to study bone loss after cessation of ovarian function. Previously we demonstrated bone loss associated with an osteoblastic insufficiency at 4 months after ovariohysterectomy (OHX). This study was designed to evaluate by four sequential monthly bone biopsies the development and course of the histologic bone abnormalities after OHX. We found cancellous bone volume, trabecular density, and wall thickness to be decreased (p < 0.05) and trabecular separation increased (p < 0.05) as early as 1 month after OHX. After 2 months, there was a decrease in mineralizing surface and mineral apposition rate (p < 0.05). Volume and surface of osteoid were increased after 3 months (p < 0.05), and there was an increase in the number of osteoblasts (p < 0.01). No histologic signs of increased resorption were observed during the experiment. However, the findings of low bone volume with decreased trabecular density and increased separation without a change in trabecular plate thickness 4 weeks after OHX suggest that a dramatic increase in resorption must have taken place soon after OHX. These results point to an early phase of initiation of bone loss related to hyperresorption followed by a maintenance phase of low bone mass ascribable to an osteoblastic insufficiency. The events that stimulate the early initiating phase after cessation of ovarian function, the factors contributing to it, and the direct demonstration of hyperresorption await further studies.
Treating the aged in rural communities: the application of cognitive‐behavioral therapy for depression
Authors: Crowther Martha R. , Scogin Forrest , Johnson Norton Misti
Published: March 2010

Many rural communities are experiencing an increase in their older adult population. Older adults who live in rural areas typically have fewer resources and poorer mental and physical health status than do their urban counterparts. Depression is the most prevalent mental health problem among older adults, and 80% of the cases are treatable. Unfortunately, for many rural elders, depressive disorders are widely under‐recognized and often untreated or undertreated. Psychotherapy is illustrated with the case of a 65‐year‐old rural married man whose presenting complaint was depressive symptoms after a myocardial infarction and loss of ability to work. The case illustrates that respect for rural elderly clients' deeply held beliefs about gender and therapy, coupled with an understanding of their limited resources, can be combined with psychoeducational and therapeutic interventions to offer new options. © 2010 Wiley Periodicals, Inc. J Clin Psychol: In Session 66:1–11, 2010.
Estrogen regulated expression of the p21Waf1/Cip1 gene in estrogen receptor positive human breast cancer cells
Authors: Mandal Soma , Davie James R.
Published: March 2010

The cyclin‐dependent kinase inhibitor protein p21Waf1/Cip1 is a potent tumor suppressor. Here, we demonstrate that estradiol regulates the p21Waf1/Cip1 gene. Estradiol induces p21Waf1/Cip1 mRNA expression within 30–60 min independent of new protein synthesis in the estrogen receptor α (ERα) positive human breast cancer cell line MCF‐7. Similar to other estradiol responsive promoters, the p21Waf1/Cip1 upstream promoter region has several estrogen response element (ERE) half‐sites nestled in AP‐1 binding sites, which are positioned upstream to Sp1 binding sites. Using the chromatin immunoprecipitation (ChIP) assay, we show that estradiol stimulation resulted in the recruitment of transcription factors ERα, Sp1, and Sp3 to the p21Waf1/Cip1 upstream promoter element. The Sp1 inhibitor mithramycin A abrogated Sp1, and to a lesser extent Sp3 binding, and markedly reduced the estradiol stimulated p21Waf1/Cip1 gene expression. However, ERα binding was not affected in the mithramycin A and estradiol treated cells. On closer examination of the half‐site ERE/AP‐1 sites upstream to the Sp1 sites in a separate ChIP experiment, we found a pronounced association of ERα upon estradiol treatment compared to almost negligible binding of Sp1 or Sp3. Together these studies provide evidence that ERα is recruited to the half‐site ERE/AP‐1 sites in the p21Waf1/Cip1 upstream promoter element. Although Sp1/Sp3 is not involved in the recruitment of ERα to the promoter, Sp1 is necessary for estrogen‐induced p21Waf1/Cip1 promoter activity. J. Cell. Physiol. 224:28–32, 2010 © 2010 Wiley‐Liss, Inc.
Epitope mapping of function‐blocking monoclonal antibody CM6 suggests a “weak” integrin binding site on the laminin‐332 LG2 domain
Authors: Yamashita Hironobu , Shang Meiling , Tripathi Manisha , Jourquin Jerome , Georgescu Walter , Liu Shanshan , Weidow Brandy , Quaranta Vito
Published: March 2010

Laminin‐332 (Ln‐332) is an extracellular matrix molecule that regulates cell adhesion, spreading, and migration by interaction with cell surface receptors such as α3β1 and α6β4. Previously, we developed a function‐blocking monoclonal antibody against rat Ln‐332, CM6, which blocks hemidesmosome assembly induced by Ln‐332‐α6β4 interactions. However, the location of its epitope on Ln‐332 has remained unclear. In this study, we show that the CM6 epitope is located on the laminin G‐like (LG)2 module of the Ln‐332 α3 chain. To specify the residues involved in this epitope, we produced a series of GST‐fused α3 LG2 mutant proteins in which rat‐specific acids were replaced with human acids by a site‐directed mutagenesis strategy. CM6 reactivity against these proteins showed that CM6 binds to the 1089NERSVR1094 sequence of rat Ln‐332 LG2 module. In a structural model, this sequence maps to an LG2 loop sequence that is exposed to solvent according to predictions, consistent with its accessibility to antibody. CM6 inhibits integrin‐dependent cell adhesion on Ln‐332 and inhibits cell spreading on both Ln‐332 and recombinant LG2 (rLG2; but not rLG3), suggesting the presence of an α3β1 binding site on LG2. However, we were unable to show that rLG2 supports adhesion in standard assays, suggesting that LG2 may contain a “weak” integrin binding site, only detectable in spreading assays that do not require washes. These results, together with our previous findings, indicate that binding sites for α3β1 and α6β4 are closely spaced in the Ln‐332 LG domains where they regulate alternative cell functions, namely adhesion/migration or hemidesmosome anchoring. J. Cell. Physiol. 223:541–548, 2010. © 2010 Wiley‐Liss, Inc.
Promotion of cell spreading and migration by vascular endothelial‐protein tyrosine phosphatase (VE‐PTP) in cooperation with integrins
Authors: Mori Munemasa , Murata Yoji , Kotani Takenori , Kusakari Shinya , Ohnishi Hiroshi , Saito Yasuyuki , Okazawa Hideki , Ishizuka Tamotsu , Mori Masatomo , Matozaki Takashi
Published: March 2010

Vascular endothelial‐protein tyrosine phosphatase (VE‐PTP) is a receptor‐type protein tyrosine phosphatase with a single catalytic domain in its cytoplasmic region and multiple fibronectin type III‐like domains in its extracellular region. VE‐PTP is expressed specifically in endothelial cells and is implicated in regulation of angiogenesis. The molecular basis for such regulation by VE‐PTP has remained largely unknown, however. We now show that forced expression of VE‐PTP promoted cell spreading as well as formation of lamellipodia and filopodia in cultured fibroblasts plated on fibronectin. These effects of VE‐PTP on cell morphology required its catalytic activity as well as activation of integrins and Ras. In addition, VE‐PTP‐induced cell spreading and lamellipodium formation were prevented by inhibition of Src family kinases or of Rac or Cdc42. Indeed, forced expression of VE‐PTP increased the level of c‐Src phosphorylation at tyrosine‐416. Moreover, the VE‐PTP‐induced changes in cell morphology were suppressed by expression of dominant negative forms of FRG or Vav2, both of which are guanine nucleotide exchange factors for Rho family proteins and are activated by tyrosine phosphorylation. Forced expression of VE‐PTP also enhanced fibronectin‐dependent migration of cultured fibroblasts. Conversely, depletion of VE‐PTP by RNA interference in human umbilical vein endothelial cells or mouse endothelioma cells inhibited cell spreading on fibronectin. These results suggest that VE‐PTP, in cooperation with integrins, regulates the spreading and migration of endothelial cells during angiogenesis. J. Cell. Physiol. 224:195–204, 2010 © 2010 Wiley‐Liss, Inc.
Esterification activities of non‐commercial lipases after pre‐treatment in pressurized propane
Authors: Kuhn Graciele , Marangoni Marluci , Freire Denise M. G. , Soares Valéria Ferreira , de Godoy Mateus Gomes , de Castro Aline Machado , Luccio Marco Di , Treichel Helen , Mazutti Marcio A. , Oliveira Débora , Oliveira J. Vladimir
Published: March 2010

BACKGROUND: The objective of this work was to assess the influence of propane pre‐treatment on the esterification activities of two non‐commercial lipases from Penicillium simplicissimum and Aspergillus parasiticus in the lyophilized and immobilized forms, evaluating the effect of pressure, exposure time and depressurization rate on the lipase activity by a full 23 experimental design.

RESULTS: For both lyophilized and immobilized lipases from all sources evaluated, enhancement in residual activities after incubation in pressurized propane was observed, under several experimental conditions. The highest increment (427%) occurred with the lyophilized enzyme from P. simplicissimum was maintained pressurized at 30 bar for 1 h and then depressurized at the fastest rate (20 bar min−1).

CONCLUSION: The enzyme activity changes significantly depending on the enzyme source, its presentation form, and the experimental pre‐treatment conditions investigated, such as exposure time, depressurization rate and pressure. The results obtained here can contribute as a basis for the selection of appropriate operational conditions, so that these catalysts can be applied in biotransformation reactions. Copyright © 2010 Society of Chemical Industry
Prey capture in frogs: alternative strategies, biomechanical trade‐offs, and hierarchical decision making
Authors: Monroy Jenna A. , Nishikawa Kiisa
Published: March 2010

Frogs exhibit flexible repertoires of prey‐capture behavior, which depend primarily on visual analysis of prey attributes. We review three examples of how visual cues are used to modulate prey‐capture strategies. (1) Dyscophus guineti modulates tongue aiming in response to prey location. These frogs turn only their heads to apprehend prey located at azimuths <40°. At azimuths >40°, the frogs switch from this strategy to one in which both head and tongue are aimed toward prey. (2) Rana pipiens modulates its feeding behavior in response to prey size, using tongue prehension for capturing small prey but switching to jaw prehension to capture large prey. (3) In Cyclorana novaehollandiae, visual processing of prey attributes involves hierarchical decision making. These frogs first assess prey size. For large prey, they ignore velocity but not shape. For small prey, they ignore shape but not velocity. Alternative prey‐capture strategies are associated with biomechanical trade‐offs that result from the interaction between the feeding apparatus and varying attributes of prey. Alternative strategies likely exist because biomechanical constraints prevent any one strategy from being effective over a range of prey attributes. Taken together, these studies emphasize the requirement that predators must somehow tune prey‐capture kinematics simultaneously to multiple attributes of prey. In frogs, the choice among alternative prey‐capture strategies involves a hierarchical decision‐making process. Hierarchical decision making is expected to be widespread among animals. However, no previous studies were found except for humans, who frequently use this type of approach to make complex decisions. J. Exp. Zool. 315:61–71, 2011. © 2010 Wiley‐Liss, Inc.
Direct analysis of lipids in mouse brain using electrospray droplet impact/SIMS
Authors: Asakawa Daiki , Yoshimura Kentaro , Takeda Sen , Hiraoka Kenzo
Published: March 2010

Electrospray droplet impact (EDI)/secondary ion mass spectrometry (SIMS) is a new desorption/ionization technique for mass spectrometry in which highly charged water clusters produced from the atmospheric‐pressure electrospray are accelerated in vacuum by 10 kV and impact the sample deposited on the metal substrate. EDI/SIMS was shown to enhance intact molecular ion formation dramatically compared to conventional SIMS. EDI/SIMS has been successfully applied to the analysis of mouse brain without any sample preparation. Five types of lipids, i.e. phosphatidylcholine (PC), phosphatidylserine, phosphatidylinositol (PI), galactocerebroside (GC) and sulfatide (ST), were readily detected from mouse brain section. In addition, by EDI/SIMS, six different regions of the mouse brain (cerebral cortex, corpus callosum, striatum, medulla oblongata, cerebellar cortex and cerebellar medulla) were examined. While GCs and STs were found to be rich in white matter, PIs were rich in gray matter. Copyright © 2010 John Wiley & Sons, Ltd.
Hydride transfer reactions via ion–neutral complex: fragmentation of protonated N‐benzylpiperidines and protonated N‐benzylpiperazines in mass spectrometry
Authors: Chai Yunfeng , Jiang Kezhi , Pan Yuanjiang
Published: March 2010

An ion‐neutral complex (INC)‐mediated hydride transfer reaction was observed in the fragmentation of protonated N‐benzylpiperidines and protonated N‐benzylpiperazines in electrospray ionization mass spectrometry. Upon protonation at the nitrogen atom, these compounds initially dissociated to an INC consisting of [RC6H4CH2]+ (R = substituent) and piperidine or piperazine. Although this INC was unstable, it did exist and was supported by both experiments and density functional theory (DFT) calculations. In the subsequent fragmentation, hydride transfer from the neutral partner to the cation species competed with the direct separation. The distribution of the two corresponding product ions was found to depend on the stabilization energy of this INC, and it was also approved by the study of substituent effects. For monosubstituted N‐benzylpiperidines, strong electron‐donating substituents favored the formation of [RC6H4CH2]+, whereas strong electron‐withdrawing substituents favored the competing hydride transfer reaction leading to a loss of toluene. The logarithmic values of the abundance ratios of the two ions were well correlated with the nature of the substituents, or rather, the stabilization energy of this INC. Copyright © 2010 John Wiley & Sons, Ltd.
Molecular dynamics simulations of MALDI: laser fluence and pulse width dependence of plume characteristics and consequences for matrix and analyte ionization
Authors: Knochenmuss Richard , Zhigilei Leonid V.
Published: March 2010

Molecular dynamics simulations of matrix‐assisted laser desorption/ionization were carried out to investigate laser pulse width and fluence effects on primary and secondary ionization process. At the same fluence, short (35 or 350 ps) pulses lead to much higher initial pressures and ion concentrations than longer ones (3 ns), but these differences do not persist because the system relaxes toward local thermal equilibrium on a nanosecond timescale. Higher fluences accentuate the initial disparities, but downstream differences are not substantial. Axial velocities of ions and neutrals are found to span a wide range, and be fluence dependent. Total ion yield is only weakly dependent on pulse width, and consistent with experimental estimates. Secondary reactions of matrix cations with analyte neutrals are efficient even though analyte ions are ablated in clusters of matrix. Copyright © 2010 John Wiley & Sons, Ltd.
Gas phase isomeric differentiation of oleanolic and ursolic acids associated with heptakis‐(2,6‐di‐O‐methyl)‐β‐cyclodextrin by electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry
Authors: Yu Zhan , Cui Meng , Yan Cunyu , Song Fengrui , Liu Zhiqiang , Liu Shuying , Zhang Hongxing
Published: March 2010

Oleanolic acid (OA) and ursolic acid (UA) are isomeric triterpenoid compounds with similar pharmaceutical properties. Usually, modern chromatographic and electrophoretic methods are widely utilized to differentiate these two compounds. Compared with mass spectrometric (MS) methods, these modern separation methods are both time‐ and sample‐consuming. Herein, we present a new method for structural differentiation of OA and UA by Fourier transform ion cyclotron resonance mass spectrometry (FT‐ICR MS) with the association of heptakis‐(2,6‐di‐O‐methyl)‐β‐cyclodextrin (DM‐β‐CD). Exact MS and tandem MS (MS/MS) data showed that there is no perceptible difference between OA and UA, as well as their β‐cyclodextrin and γ‐cyclodextrin complexes. However, there is a remarkable difference in MS/MS spectra of DM‐β‐CD complexes of OA and UA. The peak corresponding to the neutral loss of a formic acid and a water molecule could only be observed in the MS/MS spectrum of the complex of DM‐β‐CD : OA. Molecular modeling calculations were also employed to further investigate the structural differences of DM‐β‐CD : OA and DM‐β‐CD : UA complexes. Therefore, by employing DM‐β‐CD as a reference reagent, OA and UA could be differentiated with purely MS method. Copyright © 2010 John Wiley & Sons, Ltd.
Mass spectrometry of fluorocarbon‐labeled glycosphingolipids
Authors: Li Yunsen , Arigi Emma , Eichert Heather , Levery Steven B.
Published: March 2010

A method for generation of novel fluorocarbon derivatives of glycosphingolipids (GSLs) with high affinity for fluorocarbon phases has been developed, and their potential applications to mass spectrometry (MS)‐based methodologies for glycosphingolipidomics have been investigated. Sphingolipid ceramide N‐deacylase (SCDase) is used to remove the fatty acid from the ceramide moiety, after which a fluorocarbon‐rich substituent (F‐Tag) is incorporated at the free amine of the sphingoid. In initial trials, a neutral GSL, globotriaosylceramide (Gb3Cer), three purified bovine brain gangliosides, and four fungal glycosylinositol phosphorylceramides (GIPCs) were de‐N‐acylated, derivatized by prototype F‐Tags, and recovered by solid phase extraction on fluorocarbon‐derivatized silica (F‐SPE). The efficacy of SCDase treatment of GIPCs was here demonstrated for the first time. Compatibility with subsequent per‐N,O‐methylation was established for the F‐tagged Gb3 Cer and purified gangliosides, and extensive mass spectra (MS1 and MS2) consistent with all of the expected products were acquired. The potential use of F‐tagged derivatives for a comprehensive MS based profiling application was then demonstrated on a crude ganglioside mixture extracted from bovine brain. Finally, a simple trial in microarray format demonstrated fixation of F‐tagged GM1 ganglioside to a fluorous glass surface, with the glycan intact and available for interaction with a fluorescent derivative of cholera toxin B chain. The methods described thus provide a new avenue for rapid GSL recovery or cleanup, potentially compatible with a variety of platforms for mass spectrometric profiling and structure analysis, as well as parallel analysis of functional interactions. Copyright © 2010 John Wiley & Sons, Ltd.
A study of the cesium cation bonding to carboxylate anions by the kinetic method and quantum chemical calculations
Authors: Mayeux Charly , Gal Jean‐François , Charles Laurence , Massi Lionel , Maria Pierre‐Charles , Tammiku‐Taul Jaana , Lohu Ene‐Liis , Burk Peeter
Published: March 2010

Collision‐induced dissociation (CID) of the Cs+ heterodimer adducts of the nitrate anion (NO3−) and a variety of substituted benzoates (XBenz−) [(XBenz−)(Cs+)(NO3−)]− produces essentially nitrate and benzoate ions. A plot of the natural logarithm of their intensity ratio, ln[I (NO3−)/I(XBenz−)], versus the calculated cesium cation affinity (DFT B3LYP) of the substituted benzoate ions (equivalent to the enthalpy of heterolytic dissociation of the salt) is reasonably linear. This suggests that the kinetic method can be used as a source of data on the intrinsic interaction between the anionic and the cationic moieties in a salt. Copyright © 2010 John Wiley & Sons, Ltd.
Osteoblastic differentiation of human and equine adult bone marrow‐derived mesenchymal stem cells when BMP‐2 or BMP‐7 homodimer genetic modification is compared to BMP‐2/7 heterodimer genetic modification in the presence and absence of dexamethasone
Authors: Carpenter Ryan S. , Goodrich Laurie R. , Frisbie David D. , Kisiday John D. , Carbone Beth , McIlwraith C. Wayne , Centeno Christopher J. , Hidaka Chisa
Published: March 2010

Bone marrow‐derived mesenchymal stem cells (BMDMSCs) have been targeted for use in enhancement of bone healing; and their osteogenic potential may be further augmented by genes encoding bone morphogenetic proteins (BMP's). The purpose of this study was to compare the effect of genetic modification of human and equine BMDMSCs with BMP‐2 or ‐7 or BMP‐2 and ‐7 on their osteoblastogenic differentiation in the presence or absence of dexamethasone. The BMDMSCs were harvested from the iliac crest of three human donors and tuber coxae of three equine donors. Monolayer cells were genetically modified using adenovirus vectors encoding BMP‐2, ‐7 or both and cultured in the presence or absence of dexamethasone. Expression of BMPs was confirmed by enzyme linked immunosorbent assay (ELISA). To evaluate osteoblastic differentiation, cellular morphology was assessed every other day and expression and secretion of alkaline phosphatase (ALP), as well as expression levels of osteonectin (OSTN), osteocalcin (OCN), and runt‐related transcription factor‐2 (Runx2) were measured for up to 14 days. Human and equine BMDMSCs showed a capacity for osteogenic differentiation regardless of genetic modification or dexamethasone supplementation. Dexamethasone supplementation was more important for osteoblastogenic differentiation of equine BMDMSCs than human BMDMSCs. Genetic modification of BMDMSCs increased ALP secretion with AdBMP‐2 homodimer having the greatest effect in both human and equine cells compared to AdBMP 7 or AdBMP 2/7. BMP protein elution rates reached their maximal concentration between day 4 and 8 and remained relatively stable thereafter, suggesting that genetically modified BMDMSCs could be useful for cell‐based delivery of BMPs to a site of bone formation. Published by Wiley Periodicals, Inc. J Orthop Res 28:1330–1337, 2010
Analysis of frictional behavior and changes in morphology resulting from cartilage articulation with porous polyurethane foams
Authors: Gleghorn Jason P. , Doty Stephen B. , Warren Russell F. , Wright Timothy M. , Maher Suzanne A. , Bonassar Lawrence J.
Published: March 2010

Porous polyurethane foams (PUR) have been extensively evaluated as meniscal replacement materials and show great promise enabling infiltration of cells and fibrocartilage formation in vivo. Similar to most materials, PUR demonstrates progressive degeneration of opposing cartilage; however, the damage mechanism is impossible to determine because no information exists on the frictional properties of PUR–cartilage interfaces. The goals of this study were to characterize the frictional behavior of a cartilage–PUR interface across a range of articulating conditions and assess the resulting morphological changes to the cartilage surface following articulation. Articular cartilage was oscillated against PUR or stainless steel using phosphate‐buffered saline (PBS) and synovial fluid as lubricants. Following friction testing, cartilage and PUR samples were analyzed with environmental scanning electron microscopy and histological staining to determine changes in tissue morphology. Stribeck‐surface analysis demonstrated distinct lubrication modes; however, boundary mode lubrication was dominant in cartilage–PUR interfaces and the low‐friction pressure‐borne lubrication mechanism present in native joints was absent. Microscopy noted obvious wear, with disruption of the collagen architecture and concomitant proteoglycan loss in cartilage articulated against PUR. These data collectively point to the importance of frictional properties as design parameters for implants and materials for soft tissue replacement. Published by Wiley Periodicals, Inc. J Orthop Res 28:1292–1299, 2010
Organic‐carbon and nitrogen stocks and organic‐carbon fractions in soil under mixed pine and oak forest stands of different ages in NE Germany
Authors: Matos Eduardo S. , Freese Dirk , Śla̧zak Anna , Bachmann Ute , Veste Maik , Hüttl Reinhard F.
Published: March 2010

The objective of this work was to evaluate the C and N stocks and organic‐C fractions in soil under mixed forest stands of Scots pine (Pinus sylvestris L.) and Sessile oak (Quercus petraea [Matt.] Liebl.) of different ages in NE Germany. Treatments consisted of pure pine (age 102 y), and pine (age 90–102 y) mixed with 10‐, 35‐, 106‐, and 124‐y‐old oak trees. After sampling O layers, soils in the mineral layer were taken at two different depths (0–10 and 10–20 cm). Oak admixture did not affect total organic‐C (TOC) and N stocks considering the different layers separately. However, when the sum of TOC stocks in the organic and mineral layers was considered, TOC stocks decreased with increasing in oak age (r2 = 0.58, p < 0.10). The microbial C (CMB) was not directly correlated with increase of oak age, however, it was positively related with presence of oak species. There was an increase in the percentage of the CMB‐to‐TOC ratio with increase of oak‐tree ages. On average, light‐fraction C (CLF) comprised 68% of the soil TOC in upper layer corresponding to the highest C pool in the upper layer. CLF and heavy‐fraction C (CHF) were not directly affected by the admixture of oak trees in both layers. The CHF accounted on average for 30% and 59% of the TOC at 0–10 and 10–20 cm depths, respectively. Despite low clay contents in the studied soils, the differences in the DCB‐extractable Fe and Al affected the concentrations of the CHF and TOC in the 10–20 cm layers (p < 0.05). Admixture of oak in pine stands contributed to reduce topsoil C stocks, probably due to higher soil organic matter turnover promoted by higher quality of oak litter.
Determination of enantiomeric fractions of cypermethrin and cis‐bifenthrin in Chinese teas by GC/ECD
Authors: Kuang Hua , Miao Hong , Hou Xiaolin , Zhao Yunfeng , Shen Jianzhong , Wu Yongning
Published: March 2010

BACKGROUND: The pyrethroids cypermethrin and cis‐bifenthrin are the major pesticides used in tea plantations in China. Potential neurotoxic, genotoxic and immunotoxic effects of chronic exposure to pyrethroids have been reported. All synthetic pyrethroids are chiral compounds. There is a need to investigate the chiral transformation among isomers after tea processing in order to obtain an accurate risk assessment of these compounds.

RESULTS: The enantiomeric fraction (EF) of cis‐bifenthrin residues was close to 0.5 in all tea samples tested, showing that the levels of (+)‐isomer and (−)‐isomer were equivalent and there was no preferential degradation. However, the patterns of EFs of cypermethrin residues varied depending on the type of tea. The EF of isomer 1R‐3R‐αS increased in black and dark tea samples (EF = 0.200–0.343) compared with the reference cypermethrin commercial mixture (EF = 0.116). In one oolong tea sample it was found that the relative abundance of some isomers was preferentially enhanced: 1R‐3R‐αS (EF = 0.260), 1S‐3S‐αR (EF = 0.263) and 1R‐3S‐αS/1S‐3R‐αR (the last elution peak, EF = 0.275). The relationship between EF and compound concentration was also analysed, showing that the variation in EFs of cypermethrin was concentration‐dependent.

CONCLUSION: These findings appear to be useful for assessing the species‐specific risk of exposure to cypermethrin and cis‐bifenthrin. Copyright © 2010 Society of Chemical Industry
Optimisation of microwave‐assisted extraction of polysaccharides from Cyclocarya paliurus (Batal.) Iljinskaja using response surface methodology
Authors: Xie Jian‐Hua , Xie Ming‐Yong , Shen Ming‐Yue , Nie Shao‐Ping , Li Chang , Wang Yuan‐Xing
Published: March 2010

BACKGROUND: Cyclocarya paliurus (Batal.) Iljinskaja is a well‐known edible and medicinal plant in China and is commonly called the ‘sweet tea tree’. It has been reported to have a broad range of therapeutic and nutritional values in lowering blood sugar, blood lipids and blood pressure. However, much of the annual C. paliurus production is wasted. Recent reports have suggested that polysaccharides are the main active ingredients responsible for the observed bioactivities of C. paliurus. In this study, response surface methodology was used to determine the optimal conditions for microwave‐assisted extraction (MAE) of polysaccharides from C. paliurus.

RESULTS: The optimal conditions for MAE of polysaccharides were a duration of microwave radiation of 20.8 min, a temperature of 100.9 °C and a water/material ratio of 22.1:1. Under these conditions the yield of polysaccharides was up to 5.04 ± 0.09%. Compared with conventional heat reflux extraction and ultrasound‐assisted extraction, MAE of polysaccharides from C. paliurus (Batal.) Iljinskaja saved a lot of time and gave the highest yield.

CONCLUSION: The present study suggests that MAE is a good alternative method for the extraction of polysaccharides from C. paliurus (Batal.) Iljinskaja. Copyright © 2010 Society of Chemical Industry
Ionic liquid as extraction agent for detection of volatile phenols in wastewater and its regeneration
Authors: Ni Hui‐qiong , Dong Jie , Shi Jian‐jun , Wang Wei
Published: March 2010

Volatile phenols in the wastewater provide a basic parameter of the pollution. Spectrophotometric method based on the reactions of the individual phenols with 4‐aminoantipyrine in the presence of an oxidizing agent is the current official analytical method in many countries. In this paper, we propose a method for extracting the resultant colored dye with ionic liquid 1‐butyl‐3‐methylimidazolium hexafluorophosphate instead of chloroform. The results revealed excellent extraction efficiency, and the used ionic liquid could be regenerated easily. The method with small volume green reagent could be potentially applied in portable devices for in situ environmental analysis.
Comprehensive 2‐D chromatography of random and block methacrylate copolymers
Authors: van Hulst Monique , van der Horst Aschwin , Kok Wim Th. , Schoenmakers Peter J.
Published: March 2010

A comprehensive 2‐D separation method was developed for the characterization of methacrylate copolymers. In both dimensions conditions were employed that give a critical separation for the homopolymer of one of the monomers in the copolymer, and exclusion behaviour for the other. The 2‐D separation was realized by using a normal‐phase column in one dimension and a reversed phase column in the other, and by precisely tuning the compositions of the two mobile phases employed. In the normal‐phase dimension mixtures of THF and n‐hexane or n‐heptane were used as mobile phase, and in the reversed‐phase dimension mixtures of ACN and THF. Moreover, stationary phase particles had to be selected for both columns that gave an exclusion window appropriate for the molecular size of the sample polymers to be characterized. The 2‐D critical chromatography principle was tested with a polystyrene (PS)‐polymethylmethacrylate (PMMA) block copolymer and with block and random polybutylmethacrylate (PBMA)‐PMMA copolymers. Ideally, the retention time for a copolymer in both dimensions of this system would depend on the size of only one of the blocks, or on the contribution of only one of the monomers to the size of a random copolymer. However, it was found that the elution of the PS‐PMMA block copolymer depended on the size of both blocks, even when the corresponding homopolymer of one of the monomers showed critical elution behaviour. Therefore, the method could not be calibrated for block sizes by using homopolymer standards alone. Still, it was shown that the method can be used to determine differences between samples (PS‐PMMA and PBMA‐PMMA) with respect to total molecular size or block sizes separately, or to average size and chemical composition for random copolymers. Block and random PBMA‐PMMA copolymers showed a distinctly different pattern in the 2‐D plots obtained with 2‐D critical chromatography. This difference was shown to be related to the different procedures followed in the polymerization process, and the different molecular distributions resulting from these.
Response surface optimization of ultrasound‐assisted flavonoids extraction from the flower of Citrus aurantium L. var. amara Engl
Authors: Yang Li , Cao Ya‐Lan , Jiang Jian‐Guo , Lin Qing‐Sheng , Chen Jian , Zhu Liang
Published: March 2010

Citrus aurantium L. var. amara Engl is a member of genus Citrus (Rutaceae) and has been used in Chinese medicine with the effectiveness of digestant and expectorant. Ultrasonic‐assisted extraction process for maximum flavonoids from the flower of Citrus aurantium L. var. amara Engl was investigated by response surface methodology. Through single factor experiment, ranges of the main variables (including ethanol concentration, solid/liquid ratio, extraction time and temperature) affecting the extraction yield of flavonoids were confirmed. Box–Behnken central composite design consisting of 24 experimental runs and 5 replicates at zero point was then applied and a regress model was obtained to predict the optimal extraction yield. The ANOVA indicated that the regression equation fits very well with the actual situation, reflecting the relationship between the extraction yield of flavonoids and extraction conditions. The optimal conditions were as follows: extraction temperature 72.11°C, time 51.89 min, ethanol concentration 51.19% and liquid/solid ratio of 40:10. Under the optimal conditions, the maximum response value of yield (1.88%) was consistent with the experimental value (1.87%), indicating the feasibility and validation of response surface methodology in optimizing the extraction of flavonoids from the flower of Citrus aurantium L. var. amara Engl.
Hydrophobic interaction membrane chromatography for plasmid DNA purification: Design and optimization
Authors: Pereira Luís Raiado , Prazeres D. Miguel F. , Mateus Marília
Published: March 2010

Chromatography is one of the key operations in the downstream processing of plasmid DNA (pDNA). However, the increased demand for highly purified pDNA experienced in recent years has made clear the need for alternative processes capable of retaining the advantages of conventional chromatography, such as selectivity, while providing increased throughput at a lower cost. The work presented in this article outlines the development and optimization of an alternative hydrophobic interaction membrane chromatography process for the purification of pDNA. The studies included the modification of functionalized membrane supports with a linear alkyl chain ligand and the testing of chromatographic performance of these membranes. Three modification procedures were tested and the membranes were screened for their capacity and selectivity. The modified membranes could separate the model plasmid pVAX1‐LacZ (6050 bp) from impurities in clarified Escherichia coli cell lysates (specifically RNA), with good resolution. Subsequent optimization of elution profiles with the best‐performing modified membrane, resulted in a high purification factor of 4.7, competitive with its bead process counterpart, and a plasmid yield of 73%.
The epidemiology of juvenile onset recurrent respiratory papillomatosis derived from a population level national database
Authors: Campisi Paolo , Hawkes Michael , RN Kim Simpson ,   Canadian Juvenile Onset Recurrent Respiratory Papillomatosis Working Group
Published: March 2010

Objectives/Hypothesis:

To develop a national database of cases of juvenile onset recurrent respiratory papillomatosis (JoRRP) in Canada, to calculate trends in incidence and prevalence of JoRRP from January 1994 to December 2007 at the national and regional level, and to mathematically model the natural history of JoRRP.

Study Design:

Retrospective, multicenter study.

Methods:

Patient demographics, clinical presentation, human papillomavirus status, method and timing of treatment, and indicators of disease severity were captured with a standardized case report form. Operative records were retrospectively scored using the Derkay‐Coltrera staging system for each operative intervention. Trends in incidence and prevalence of JoRRP from 1994 to 2007 were calculated at a national and regional level using national population census data. A multivariable mixed effects linear model was used to explore the effect of surgery‐specific variables on the intersurgical interval. Nonlinear least‐squares regression was used to model the natural history of JoRRP.

Results:

Development of a national database of children with JoRRP identified 243 cases who underwent 3,021 surgical procedures. The national incidence of JoRRP from 1994 to 2007 was 0.24 per 100,000 children aged 14 years and younger. The prevalence was 1.11 per 100,000 children. The natural history of JoRRP followed a nonlinear time course with 64% of cases having a decreasing annual rate of surgery over time.

Conclusions:

A Canadian national database of children with JoRRP was successfully developed. Modeling of the natural history of JoRRP may have important clinical and research implications. Laryngoscope, 2010
Effects of different quality plant residues on soil carbon accumulation and aggregate formation in a tropical sandy soil in Northeast Thailand as revealed by a 10‐year field experiment
Authors: Samahadthai P. , Vityakon P. , Saenjan P.
Published: March 2010

Particulate organic matter (POM) plays important role in soil organic carbon (SOC) retention and soil aggregation. This paper assesses how quality (chemical composition) of four different‐quality organic residues applied annually to a tropical sandy loam soil for 10 years has affected POM pools and the development of soil aggregates. Water‐stable aggregate size distribution (>2, 0·25–2, 0·106–0·25 mm) was determined through wet sieving. Density fractionation was employed to determine POM (light—LF, and heavy—HF fractions, 0·05–1 mm). Tamarind leaf litter showed the highest SOC (<1 mm) accumulation, while rice straw showed the lowest. LF‐C contents had positive correlations with high contents of C and recalcitrant constituents, (i.e. lignin and polyphenols) of the residues. Dipterocarp, a resistant residue, showed the highest LF‐C, followed by the intermediate residues, tamarind, and groundnut, whereas HF was higher in groundnut and tamarind than dipterocarp residues. Rice straw had the lowest LF‐ and HF‐C contents. Tamarind had the highest quantity (51 per cent) of small macroaggregates (0·25–2 mm), while dipterocarp had the most (2·1 per cent) large macroaggregates (>2 mm). Rice straw had the lowest quantities of both macroaggregates. Similar to small‐sized HF (0·05–0·25 mm), small macroaggregates had positive correlation with N and negative correlation with C/N ratios, while large macroaggregates had positive correlations with C and recalcitrant constituents of the residues. Tamarind, with intermediate contents of N and recalcitrant compounds, appears to best promote small macroaggregate formation. Carbon stabilized in small macroaggregates accounted for the tamarind treatment showing the largest SOC accumulation. Copyright © 2010 John Wiley & Sons, Ltd.
Improving the Heat Resistance of Ribonuclease A by the Addition of Poly(N,N‐diethylaminoethyl methacrylate)‐graft‐poly(ethylene glycol) (PEAMA‐g‐PEG)
Authors: Ganguli Sumon , Yoshimoto Keitaro , Tomita Shunsuke , Sakuma Hiroshi , Matsuoka Tsuneyoshi , Shiraki Kentaro , Nagasaki Yukio
Published: March 2010

Poly(N,N‐diethylaminoethyl methacrylate)‐graft‐poly(ethylene glycol) (PEAMA‐g‐PEG) has previously been used as a novel additive to improve the heat resistance of lysozyme, which has a positive net charge and a negatively charged active site. In the present study, we show that PEAMA‐g‐PEG prevents heat inactivation of ribonuclease A (RNase A), which has a positive net charge and a positively charged active site. After treatment at 98 °C for 10 min, the enzymatic activity of RNase A complexed with PEAMA‐g‐PEG was maintained at up to 75% of the level of the native RNase A. The extents of inactivation of RNase A and the complex of RNase A with PEAMA‐g‐PEG were strongly dependent upon the heating temperature and incubation time. Circular dichroism (CD) spectral analysis revealed that heat‐induced irreversible inactivation was largely suppressed when RNase A was complexed with PEAMA‐g‐PEG. These findings suggest that the heat resistance of RNase A is improved by the external addition of PEAMA‐g‐PEG.

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