bluuebunny/crossref_metadata_2025 huggingface dataset:
Bioceramic inlays do not improve mechanical incorporation of grit‐blasted titanium stems in the proximal sheep femur
Authors: Keränen Pauli , Koort Jyri , Itälä Ari , Ylänen Heimo , Dalstra Michel , Hupa Mikko , Kommonen Bertel , Aro Hannu T.
Published: May 2009

The aim of the present study was to determine, if bioactive glass (BG) surface inlays improve osseointegration of titanium implants in the proximal femur of adult sheep. In simulation of uncemented primary stems (nine animals), only the proximal part of the implants was grit‐blasted and three surface slots of the grit‐blasted region were filled with sintered BG microspheres. Primary stems were implanted using press‐fit technique. In revision stem simulation (eight animals), grit‐blasting was extended over the whole implant and seven perforating holes of the stem were filled by sintered BG granules. Revision stems were implanted with a mixture of autogenous bone graft and BG granules. Comparison with solid partially or fully grit‐blasted control stems implanted in the contralateral femurs was performed in the primary and revision stem experiments at 12 and 25 weeks, respectively. Implant incorporation was evaluated by torsional failure testing and histomorphometry. Only one‐third of the primary stems anchored mechanically to bone. The revision stems incorporated better and the BG inlays of the revision stems showed ingrowth of new bone. However, there were no significant differences in the torsional failure loads between the stems with BG inlays and the control stems. In conclusion, surface BG inlays gave no measurable advantage in mechanical incorporation of grit‐blasted titanium implants. Overall, the proximal sheep femur, characterized by minimal amount of cancellous bone and the presence of adipocytic bone marrow, seemed to present compromised bone healing conditions. © 2009 Wiley Periodicals, Inc. J Biomed Mater Res, 2010
Bone ingrowth into porous silicon nitride
Authors: Anderson M. C. , Olsen R.
Published: May 2009

Achieving solid skeletal attachment is a requirement for the clinical success of orthopedic implants. Porous or roughened surfaces and coatings have been developed and used with mixed success to achieve attachment due to bone ingrowth. Silicon nitride is a high performance ceramic whose strength, imaging properties, and biocompatibility make it a candidate material for orthopedic implants. A porous form of silicon nitride, cancellous‐structured ceramic (CSC), has been developed. CSC is a nonresorbable, partially radiolucent porous structure that can be bonded to orthopedic implants made of silicon nitride to facilitate skeletal attachment. The purpose of this study was to quantify the extent and rate of bone ingrowth into CSC in a large animal model. Cylindrical implants were placed bilaterally using staged surgeries in the medial femoral condyle of six sheep. Condyles were retrieved after 3 and 6 months in situ and prepared for examination of bone growth under SEM. Bone grew into CSC to extents and at rates similar to those reported for other titanium porous surfaces in studies involving large animals and postmortem retrievals in humans. Bone ingrowth was observed at depths of penetration greater than 3 mm in some implants after only 12 weeks in situ. Bone ingrowth into CSC is a viable method for achieving skeletal attachment. © 2009 Wiley Periodicals, Inc. J Biomed Mater Res, 2010
Fragmin/protamine microparticles as cell carriers to enhance viability of adipose‐derived stromal cells and their subsequent effect on in vivo neovascularization
Authors: Nakamura Shingo , Kishimoto Satoko , Nakamura Shin‐ichiro , Nambu Masaki , Fujita Masanori , Tanaka Yoshihiro , Mori Yasutaka , Tagawa Masahiro , Maehara Tadaaki , Ishihara Masayuki
Published: May 2009

We prepared fragmin/protamine microparticles (F/P MPs) as cell carriers to enhance cell viability. Use of material consisting of a low‐molecular‐weight heparin (fragmin) mixed with protamine resulted in water‐insoluble microparticles (about 0.5–1 μm in diameter). In this study, we investigated the capability of F/P MPs to enhance the viabilities of human microvascular endothelial cells (HMVECs), human dermal fibroblasts (fibroblasts), and adipose tissue‐derived stromal cells (ATSCs) in suspension culture. F/P MPs were bound to the surfaces of these cells, and the interaction of these cells with F/P MPs induced cells/F/P MPs‐aggregate formations in vitro, and maintained viabilities of those cells for at least 3 days. The ATSCs/F/P MPs‐aggregates adhered to and grew on suspension culture plates in a fashion similar to those on type I collagen‐coated plates. The cultured ATSCs secreted significant amounts of angiogenic heparin‐binding growth factors such as FGF‐2. When the ATSCs/F/P MPs‐aggregates were subcutaneously injected into the back of nude mice, significant neovascularization and fibrous tissue formation were induced near the site of injection from day 3 to week 2. The ATSCs/F/P MPs‐aggregates were thus useful and convenient biomaterials for cell‐therapy of angiogenesis. © 2009 Wiley Periodicals, Inc. J Biomed Mater Res, 2010
In vitro biocompatibility evaluation of surface‐modified titanium alloys
Authors: Treves Cristina , Martinesi Maria , Stio Maria , Gutiérrez Alejandro , Jiménez José Antonio , López María Francisca
Published: May 2009

The present work is aimed to evaluate the effects of a surface modification process on the biocompatibility of three vanadium‐free titanium alloys with biomedical applications interest. Chemical composition of alloys investigated, in weight %, were Ti‐7Nb‐6Al, Ti‐13Nb‐13Zr, and Ti‐15Zr‐4Nb. An easy and economic method intended to improve the biocompatibiblity of these materials consists in a simple thermal treatment at high temperature, 750°C, in air for different times. The significance of modification of the surface properties to the biological response was studied putting in contact both untreated and thermally treated alloys with human cells in culture, Human Umbilical Vein Endothelial Cells (HUVEC) and Human Peripheral Blood Mononuclear Cells (PBMC). The TNF‐α release data indicate that thermal treatment improves the biological response of the alloys. The notable enhancement of the surface roughness upon oxidation could be related with the observed reduction of the TNF‐α levels for treated alloys. A different behavior of the two cell lines may be observed, when adhesion molecules (ICAM‐1 and VCAM‐1 in HUVEC, ICAM‐1, and LFA‐1 in PBMC) were determined, PBMC being more sensitive than HUVEC to the contact with the samples. The data also distinguish surface composition and corrosion resistance as significant parameters for the biological response. © 2009 Wiley Periodicals, Inc. J Biomed Mater Res, 2010
Melatonin and its brain metabolite N1‐acetyl‐5‐methoxykynuramine prevent mitochondrial nitric oxide synthase induction in parkinsonian mice
Authors: Tapias Víctor , Escames Germaine , López Luis C. , López Ana , Camacho Encarnación , Carrión María D. , Entrena Antonio , Gallo Miguel A. , Espinosa Antonio , Acuña‐Castroviejo Darío
Published: May 2009

Melatonin prevents mitochondrial failure in models of sepsis through its ability to inhibit the expression and activity of both cytosolic (iNOS) and mitochondrial (i‐mtNOS) inducible nitric oxide synthases. Because Parkinson's disease (PD), like sepsis, is associated with iNOS induction, we assessed the existence of changes in iNOS/i‐mtNOS and their relation with mitochondrial dysfunction in the MPTP model of PD, which also displays increased iNOS expression. We also evaluated the role of melatonin (aMT) and its brain metabolite, N1‐acetyl‐5‐methoxykynuramine (AMK), in preventing i‐mtNOS induction and mitochondrial failure in this model of PD. Mitochondria from substantia nigra (SN) and, to a lesser extent, from striatum (ST) showed a significant increase in i‐mtNOS activity, nitrite levels, oxidative stress, and complex I inhibition after MPTP treatment. MPTP‐induced i‐mtNOS was probably related to mitochondrial failure, because its prevention by aMT and AMK reduced oxidative/nitrosative stress and restored complex I activity. These findings represent the first experimental evidence of a potential role for i‐mtNOS in the mitochondrial failure of PD and support a novel mechanism in the neuroprotective effects of aMT and AMK. © 2009 Wiley‐Liss, Inc.
Non‐negative Matrix Factorization for the identification of patterns of atmospheric pressure and geopotential for the Northern Hemisphere
Authors: Schlink Uwe , Thiem Alexander
Published: May 2009

As the atmospheric system is characterized by highly complex interactions between a large number of physical variables, it is a challenging task for researchers to break up the complicated structures into a few significant modes of variability.

An innovative technique, called Non‐negative Matrix Factorization (NMF), developed to provide a reduced‐dimensional representation of large‐scale non‐negative data and to extract underlying features, is introduced as a tool for meteorological applications. The method is used to decompose space‐time meteorological fields into spatial patterns and associated time indices in order to advance our knowledge of dominant atmospheric processes. For the Northern Hemisphere the 500 hPa geopotential field together with sea level pressure (SLP) are analysed using an up‐to‐date NMF algorithm as well as a helpful method of NMF initialization based on Singular Value Decomposition (SVD). Several NMF patterns correspond to the variations identified by traditional EOF analysis, such as the East Atlantic and the Pacific/North American Pattern. For the North Atlantic Oscillation the NMF identifies sub‐patterns: The positive phase is associated with systems of pressure variation over the Pacific Ocean and the Arctic, respectively, the negative phase resembles the EOF pattern.

As the NMF patterns not only represent variability, like EOF patterns, but also are fractions of the total observed values, we demonstrate for a location near Nikolski, Alaska, the temporal development of the geopotential as a superposition of NMF‐factors. Copyright © 2009 Royal Meteorological Society
A modified support vector machine based prediction model on streamflow at the Shihmen Reservoir, Taiwan
Authors: Li Pei‐Hao , Kwon Hyun‐Han , Sun Liqiang , Lall Upmanu , Kao Jehng‐Jung
Published: May 2009

The uncertainty of the availability of water resources during the boreal winter has led to significant economic losses in recent years in Taiwan. A modified support vector machine (SVM) based prediction framework is thus proposed to improve the predictability of the inflow to Shihmen reservoir in December and January, using climate data from the prior period. Highly correlated climate precursors are first identified and adopted to predict water availability in North Taiwan. A genetic algorithm based parameter determination procedure is implemented to the SVM parameters to learn the non‐linear pattern underlying climate systems more flexibly. Bagging is then applied to construct various SVM models to reduce the variance in the prediction by the median of forecasts from the constructed models. The enhanced prediction ability of the proposed modified SVM‐based model with respect to a bagged multiple linear regression (MLR), simple SVM, and simple MLR model is also demonstrated. The results show that the proposed modified SVM‐based model outperforms the prediction ability of the other models in all of the adopted evaluation scores. Copyright © 2009 Royal Meteorological Society
Repopulation of vascularized bone allotransplants with recipient‐derived cells: Detection by laser capture microdissection and real‐time PCR
Authors: Pelzer Michael , Larsen Mikko , Friedrich Patricia F. , Aleff Ross A. , Bishop Allen T.
Published: May 2009

Mechanisms underlying successful composite tissue transplantation must include an analysis of transplant chimerism, which is little studied, particularly in calcified tissue. We have developed a new method enabling determination of lineage of selected cells in our model of vascularized bone allotransplantation. Vascularized femoral allotransplantation was performed from female Dark Agouti (DA) donor rats to male Piebald Virol Glaxo (PVG) recipients, representing a major histocompatibility mismatch. Four groups differed in use of immunosuppression (±2 weeks Tacrolimus) and surgical revascularization, by implantation of either a patent or a ligated saphenous arteriovenous (AV) bundle. Results were assessed at 18 weeks. Bone blood flow was measured by the hydrogen washout technique and transverse specimens were prepared for histology. Real‐time PCR was performed on DNA from laser capture microdissected cortical bone regions to determine the extent of chimerism. To do so, we analyzed the relative expression ratio of the sex‐determining region Y (Sry) gene, specific only for recipient male rat DNA, to the cyclophilin housekeeper gene. Substantial transplant chimerism was seen in cortical bone of all groups (range 77–97%). Rats without immunosuppression and with a patent AV bundle revealed significantly higher chimerism than those with immunosuppression and a ligated AV bundle, which maintained transplant cell viability. We describe a new method to study the extent of chimerism in rat vascularized bone allotransplants, including a sex‐mismatched transplantation model, laser capture microdissection of selected bone regions, and calculation of the relative expression ratio. © 2009 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 27:1514–1520, 2009
Nomographic estimation and evaluation of soil erodibility under simulated and natural rainfall conditions
Authors: Singh M. J. , Khera K. L.
Published: May 2009

To evaluate soil erodibility under different land uses and to study the applicability of nomograph for estimation of soil erodibility a field experiment was conducted under both natural and simulated rainfall conditions under four land uses viz. barren, cultivated, grassland, and forest in the sub‐mountainous tract of Punjab (India). Measured soil erodibility (K) values varied from 0·33 to 0·67 under natural rainfall conditions and from 0·23 to 0·40 under simulated rainfall conditions. Among different land uses, measured K was in the order of barren > cultivated > grassland > forest soils. The values of the K estimated by nomograph were very low as compared to the observed values. The trends were also in contrast to these observed values of K under simulated and natural rainfall conditions. To modify nomograph equation, different ranges of aggregate sizes were correlated with soil loss. It was observed that water stable aggregates (WSA) <2 mm size had a significant correlation with soil loss under both natural (r = 0·88) and simulated (r = 0·76) rainfall conditions. So the nomograph equation was modified to include the M parameter based on WSA <2 mm size. The value of K estimated from the modified nomograph had a significant correlation with measured values of K under both the natural and simulated rainfall conditions. Copyright © 2009 John Wiley & Sons, Ltd.
4‐Alkylphenoxymethyl‐Substituted Polystyrenes for Liquid Crystal Alignment Layers
Authors: Kang Hyo , Kim Tae‐Ho , Kang Daeseung , Lee Jong‐Chan
Published: May 2009

We synthesized a phenoxymethyl‐substituted polystyrene (PHP) and a series of 4‐alkylphenoxymethyl‐substituted polystyrenes, where the alkyl group is (CH2)nH (n = 1, 2, 4, 6, and 8), using polymer analogous reactions, in order to study the effect of the phenoxymethyl and 4‐alkylphenoxymethyl side groups on the liquid crystal (LC) alignment properties. The LC cell fabricated with the rubbed PHP film exhibited homogeneous planar and perpendicular LC alignment with respect to the rubbing direction. On the contrary, the LC cells made from the 4‐alkylphenoxymethyl‐substituted polystyrenes showed homeotropic LC alignment behaviors even at a very high rubbing density of 250, regardless of the length of the alkyl groups. Previously, n‐alkylsulfonylmethyl‐substituted polystyrenes with alkyl groups having more than 8 carbons (n > 8) showed homeotropic LC alignment behavior. Therefore, the additional phenoxy group in the side chain was found to improve the homeotropic LC aligning ability of the polystyrene derivatives.

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On The Micro‐Phase Separation in Waterborne Polyurethanes
Authors: Princi Elisabetta , Vicini Silvia , Castro Kepa , Capitani Donatella , Proietti Noemi , Mannina Luisa
Published: May 2009

Some polyester and polycarbonate‐based waterborne polyurethanes (WPU) were characterised by means of several techniques, to correlate the morphology with their structures and properties. The morphological analysis carried out by transmission electron microscopy on thin sections showed that the selected polyurethanes, after purification, exhibit a nanostructured phase separation between hard and soft domains. The presence of hydrogen bonding and the hard/soft ratio were evaluated by FT IR and NMR spectroscopy. Both the thermal and the dynamic mechanical analysis allowed the polymers microstructure to be correlated with the polymer properties; two glass transition temperatures were determined, corresponding to the hard and soft domains respectively.

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Stereocomplex Crystallization and Spherulite Growth of Low Molecular Weight Poly(L‐lactide) and Poly(D‐lactide) from the Melt
Authors: Bouapao Leevameng , Tsuji Hideto
Published: May 2009

In isothermal crystallization from the melt, only stereocomplex crystallites as a crystalline species were formed in all the blends at crystallization temperature above 130 °C. The spherulite growth rate and crystallinity values decreased monotonically with deviation of the PDLA content from 50%. Surprisingly, regime analysis revealed that the crystallization mechanism of the blends was independent of PDLA content. In non‐isothermal crystallization of melt‐quenched specimens during heating, the cold crystallization of blends takes place rapidly at a lower temperature compared to that of pure PLLA and PDLA. This is attributable to the rapid stereocomplex crystallization or the nucleating effect of stereocomplex crystallites formed during quenching from the melt or second heating.

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Effect of glycosidation of isoflavones on their bioavailability and pharmacokinetics in aged male rats
Authors: Sepehr Estatira , Cooke Gerard M. , Robertson Patrick , Gilani G. Sarwar
Published: May 2009

There are limited reports on the bioavailability and pharmacokinetics of isoflavones in elderly humans and aged animals. The present study was conducted to assess the effect of glycosidation of isoflavones on their bioavailability and pharmacokinetics in aged (20 month old) male Fischer‐344 (F‐344) rats. The F‐344 rat, developed by the National Institute on Aging, is an inbred rat model that is commonly used for aging studies and resembles many features of aging humans. Three sources of isoflavones; NovasoyTM(a commercial supplement), a mixture of synthetic aglycons (daidzein, genistein and glycitein), and a mixture of synthetic glucosides (daidzin, genistin, and glycitin) were tested. Following administration, blood samples were collected at different times (0–48 h post‐oral gavage and 0–8 h post‐IV dosing). Plasma isoflavones and 7‐hydroxy‐3‐(4′‐hydroxyphenyl)‐chroman (a metabolite of daidzein) were measured by LC/MS. The extent of absorption was determined by comparing the area under the curve (AUC) of the plasma‐concentration time curve after intravenous (IV) administration with that following oral administration. The extent of bioavailability was then calculated as: %bioabailability = (AUCor/AUCIV)×(DoseIV/Doseor)×100. Bioavailabilities for genistein were significantly (p= 0.013) higher for the aglycon (35 ± 9%) compared with the glucoside forms (11 ± 3%). In contrast, the bioavailabilities for glycitein were significantly (p= 0.011) higher in Novasoy (27 ± 13%) and the glucoside form (21 ± 10%) compared with the aglycon (8 ± 3%). No significant differences in the bioavailability of daidzein were observed in aged rats dosed with aglycon, glucoside or Novasoy. However, aged rats were able to produce equol as early as 8 h post‐dosing. In summary, the source of isoflavones had significant effects on genistein and glycitein bioavailability in aged male rats.
Comparative effects of fatty acids on proinflammatory gene cyclooxygenase 2 and inducible nitric oxide synthase expression in retinal pigment epithelial cells
Authors: Fang I‐Mo , Yang Chang‐Hao , Yang Chung‐May , Chen Muh‐Shy
Published: May 2009

Dietary fat modification is a promising approach to prevent age‐related macular degeneration (AMD). However, which types of fatty acids carry a greater risk for AMD remains unclear. In this study, we compared the effects of 18‐carbon fatty acids with different degrees of unsaturation on the expression of the proinflammatory genes cyclooxygenase (COX)‐2 and inducible nitric oxide synthase (iNOS) in human retinal pigment epithelium (RPE). Additionally, we investigated whether lutein could modulate these genes induced by fatty acids in RPE. Treatment with oleic acid, linoleic acid (LA), or linolenic acid increased the expression of iNOS and COX‐2 genes and the production of prostaglandin E2and nitric oxide (NO) in RPE, whereas the saturated fatty acid stearic acid had little effect on these genes. Of the fatty acids studied, LA had the greatest effects on the induction of these genes. Furthermore, LA also induced NF‐κB transcriptional activation the most. Lutein inhibited LA‐induced expression of COX‐2 and iNOS in a dose‐dependent manner. These data suggested that specific unsaturated fatty acids, particularly LA, can stimulate RPE cells to express proinflammatory genes, which may contribute to the pathogenesis of AMD. Lutein inhibited the expression of these genes induced by LA through blockade of NF‐κB activation.
Phenethyl isothiocyanate inhibits STAT3 activation in prostate cancer cells
Authors: Gong Aiyu , He Meilan , Krishna Vanaja Donkena , Yin Ping , Karnes R. Jeffrey , Young Charles Y. F.
Published: May 2009

This study was undertaken to investigate the mechanism by which phenethyl isothiocyanate (PEITC), a natural compound from cruciferous vegetables, exhibits antitumor effect on prostate cancer cells. Cell proliferation, cell cycle, Western blot, gene transfer, and reporter assays were used to test the effects of PEITC on the growth and IL6/JAK/STAT3 pathway in prostate cancer. The result showed that PEITC significantly inhibited DU145 cell proliferation in a dose‐dependent manner and induced the cell arrest at G2‐M phase. PEITC inhibited both constitutive and IL‐6‐induced STAT3 activity in DU145 cells. IL‐6‐stimulated phosphorylation of JAK2, an STAT3 upstream kinase, was also attenuated by PEITC. Moreover, an antioxidant reagent, N‐acetyl‐L‐cysteine (NAC) which suppresses reactive oxygen species (ROS) generation, reversed the early inhibitory effects of PEITC on cell proliferation, constitutive or IL‐6‐mediated JAK‐STAT3 phosphorylation in PCa cells. Taken together, our data demonstrated that PEITC can inhibit the activation of the JAK‐STAT3 signal‐cascade in prostate cancer cells and the underlying mechanism may be partially involved with blocking cellular ROS production during the early stage of the signaling activation by IL‐6.
A link between the interleukin‐6/Stat3 anti‐apoptotic pathway and microRNA‐21 in preimplantation mouse embryos
Authors: Shen Xing‐Hui , Han Young‐Joon , Zhang Ding‐Xiao , Cui Xiang‐Shun , Kim Nam‐Hyung
Published: May 2009

Signal transducers and activators of transcription‐3 (Stat3) plays a central role in interleukin‐6 (IL‐6)‐mediated cell proliferation by inhibiting apoptosis in a variety of cell types. MicroRNA‐21 (miRNA‐21), a ubiquitous miRNA, acts as an anti‐apoptotic factor that seems to be indirectly but strictly linked to Stat3. In order to determine whether the IL‐6 induced Stat3 anti‐apoptosis pathway is linked with miRNA‐21, we first determined the effects of recombinant mouse IL‐6 on Stat3 expression, mouse embryo viability, and the mRNA levels of apoptosis related genes and miRNA‐21 during mouse embryo development in vitro. Addition of 10 or 100 ng/ml of recombinant IL‐6 to the culture medium did not affect the developmental ability of 2‐cell stage embryos into blastocysts. However, total cell number was significantly increased and apoptosis was reduced in blastocyst stage embryos cultured in the presence of 100 ng/ml of recombinant IL‐6. Furthermore, addition of recombinant IL‐6 to the culture medium significantly increased the copy numbers of anti‐apoptotic miRNA‐21, up‐regulated Bcl2l1, and down‐regulated casp3. Similarly, the injection of mature miRNA‐21 into cells up‐regulated Bcl2l1 and down‐regulated casp3. These results suggest that the induction of the Stat3 anti‐apoptotic pathway by IL‐6 is linked to miRNA‐21 expression, which possibly results in the regulation of cell apoptosis in early mouse embryo development. Mol. Reprod. Dev. 76: 854–862, 2009. © 2009 Wiley‐Liss, Inc.
Bias–variance trade‐off in pharmacoepidemiological studies using physician‐preference‐based instrumental variables: a simulation study
Authors: Ionescu‐Ittu Raluca , Delaney Joseph A.C. , Abrahamowicz Michal
Published: May 2009

Purpose

Instrumental variables (IV) methodology removes bias due to unobserved confounding by replacing in the analysis the treatment with another variable—the instrument—that is well correlated with the treatment and independent of confounders. Recently, physician drug preference, operationalized as the treatment prescribed to the previous patient of the same physician, was proposed as an instrument in database studies comparing two competing drugs. We assessed, in simulations, how the performance of the IV estimates depends on the strength of this instrument.

Methods

The ‘physician preference’ instrument correlates well with the treatment only if physician preferences affect the treatment received by a large fraction of patients. Yet, often there is a subgroup of patients whose treatment cannot be affected by physician's preferences. The larger this subgroup is, the weaker the instrument. We investigated the impact of weakening this instrument on the performance of IV estimates, by comparing risk difference estimates from the conventional and IV analyses in the presence of an unobserved confounder, for both continuous and binary outcomes.

Results

The IV estimates were uniformly less biased than the conventional estimates, but had higher variance. Accordingly, the bias–variance trade‐off favors the IV estimates only when physician' preference is a strong instrument. Still, the coverage rate of the 95%CI for the IV estimates was very close to the nominal 95%, while it was consistently lower for the conventional estimates.

Conclusion

Researchers should consider using the ‘physician preference’ instrument when comparing two competing drugs, but should be aware of the underlying assumptions. Copyright © 2009 John Wiley & Sons, Ltd.
Is physician adherence to prescription guidelines a general trait of health care practices or dependent on drug type?—A multilevel logistic regression analysis in South Sweden
Authors: Ohlsson Henrik , Merlo Juan
Published: May 2009

Purpose

Therapeutic traditions at health care practices (HCPs) influence physicians' adherence to prescription guidelines for specific drugs, however, it is not known if such traditions affect all kinds of prescriptions or only specific types of drug. Our goal was to determine whether adherence to prescription guidelines is a common trait of HCPs or dependent on drug type.

Methods

We fitted separate multi‐level logistic regression models to all patients in the Skåne region who received a prescription for a statin drug (ATC: C10AA, n = 6232), an agent acting on the renin‐angiotensin system (ATC: C09, n = 7222) or a proton pump inhibitor (ATC: A02BC, n = 11 563) at 198 HCPs from July 2006 to December 2006.

Results

There was a high clustering of adherence to prescription guidelines at HCPs for the different drug types (MORagents acting on the renin‐angiotensin system = 4.72 [95% CI: 3.90–5.92], MORStatins = 2.71 [95% CI: 2.23–3.39] and MORProton pump inhibitors =  2.16 [95% CI: 1.95–2.45]). Compared with HCPs with low adherence to guidelines in two drug types, those HCPs with the highest level of adherence for these two drug types also showed a higher probability of adherence for the third drug type.

Conclusion

Physicians' decisions to follow prescription guidelines seem to be influenced by therapeutic traditions at the HCP. Moreover, these therapeutic traditions seem to affect all kinds of prescriptions. This information can be used as basis for interventions to support rational and cost‐effective medication use. Copyright © 2009 John Wiley & Sons, Ltd.
Increased prevalence of risk factors for morbidity and mortality in the US Hispanic CF population
Authors: Watts Kimberly Danieli , Seshadri Roopa , Sullivan Christine , McColley Susanna A.
Published: May 2009

Hispanic ethnicity is an independent risk factor for increased morbidity and mortality in cystic fibrosis (CF) patients. In order to compare the prevalence of risk factors for morbidity and mortality between the Hispanic CF population and the non‐Hispanic CF population, we performed a cross‐sectional study of patients in the 2004 Cystic Fibrosis Foundation Patient Registry. Among 22,714 CF patients, 1,511 were identified as ethnic Hispanic. Hispanic patients were diagnosed earlier (2.8 vs. 3.3 years,P = 0.005) and acquiredPseudomonas aeruginosaat a younger age (6.6 years vs. 10 years,P < 0.001). FEV1was lower for Hispanic patients (81.5% vs. 87% predicted for those under 18 years old [P < 0.001] and 2.1 L vs. 2.3 L for those 18 years and older [P = 0.01]). Hispanic patients had similar or better nutritional status. Hispanic patients were more likely to be diagnosed with liver disease (OR 1.31 [1.1, 1.56]) but less likely to be diagnosed with depression (OR 0.53 [0.39, 0.68]), bone and joint disease (OR 0.55 [0.41, 0.71]), or CF‐related diabetes (OR 0.53 [0.43, 0.62]). Hispanic patients had lower median income by zip code ($41,930 vs. $47,341;P < 0.001), a higher rate of government insurance (55.2% vs. 32.0%;P < 0.001), and greater percentage of mothers with less than a high school education (26.7% vs. 6.5%;P < 0.001). We conclude that there is an increased prevalence of important risk factors for morbidity and mortality in the Hispanic CF population. Pediatr Pulmonol. 2009; 44:594–601. © 2009 Wiley‐Liss, Inc.
Tuning the lifetime of the surface plasmon upon sputtering
Authors: Politano A. , Chiarello G.
Published: May 2009

The lifetime of the surface plasmon in sputtered Ag ultrathin films on Cu(111) was investigated by high‐resolution electron energy loss spectroscopy measurements. The linewidth of the surface plasmon was found to follow a square‐root dependence on the fluence. Such finding allows the tuning of the lifetime of the plasmonic excitation upon sputtering and has general implications in plasmon‐based spectroscopies and in plasmon‐mediated processes across the films and at their surfaces. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Xanthine oxidase inhibiting effects of noni (Morinda citrifolia) fruit juice
Authors: Palu Afa , Deng Shixin , West Brett , Jensen Jarakae
Published: May 2009

Morinda citrifolia L. (noni), family Rubiaceae, has been used in Polynesia for over 2000 years for its reputed health benefits, one of which is its therapeutic effects on gout (langa e hokotanga hui). However, its healing mechanism has not been elucidated. This study showed that in an in vitro bioassay that Tahitian Noni® Juice (TNJ) inhibited xanthine oxidase (XO) concentration dependently. Concentrations of 1, 5 and 10 mg/mL of TNJ inhibited XO by 11%, 113% and 148%, respectively, with an IC50 of 3.8 mg compared with an IC50 of 2.4 µm for allopurinol. Noni fruit juice concentrate (NFJC) also inhibited XO concentration dependently. Concentrations of 1 and 5 mg/mL NFJC inhibited XO in vitro by 184% and 159%, respectively. A 0.1 mg/mL methanol extract (NFJME) from the fractionation of noni fruit puree inhibited XO by 64%. It was elucidated that the noni fruit juice inhibitory effect on XO enzymes is the mechanism by which noni ameliorates gout and gout‐like diseases. Further, the results also support the traditional usage of noni in the treatment of gout. Copyright © 2009 John Wiley & Sons, Ltd.
Stable boundary layer: Parametrizations for local and larger scales
Authors: Savijärvi Hannu
Published: May 2009

Stability functions f(Ri) for a very stable boundary layer were studied by experimenting in winter Antarctic conditions with a one‐dimensional (1D) numerical model and comparing with the Plateau Site tower observations. The local representations for f(Ri) produced good simulations of the temperature profiles and wind hodographs, while the standard Monin–Obukhov formulation indicated too little, and the general‐circulation model (GCM)‐type formulations too much, vertical mixing.

Next, idealised simulations were made for winter‐night hilly northern Finland landscape with a high‐resolution 2D model, using a local f(Ri) at each column. Realistic quasi‐steady mesoscale katabatic flows resulted. These enhanced vertical mixing both locally and regionally. Area‐averaged (i.e. regional) surface fluxes were compared with those obtained from simulations using GCM‐type large‐scale stability functions over flat land. New parametrizations for both local and larger scales are suggested based on the experiments. Copyright © 2009 Royal Meteorological Society
Diastereochemical differentiation of bicyclic diols using metal complexation and collision‐induced dissociation mass spectrometry
Authors: Pakarinen Jaana M. H. , Vainiotalo Pirjo
Published: May 2009

Metal complex formation was investigated for di‐exo‐, di‐endo‐ and trans‐2,3‐ and 2,5‐disubstituted trinorbornanediols, and di‐exo‐ and di‐endo‐ 2,3‐disubstituted camphanediols using different divalent transition metals (Co2+, Ni2+, Cu2+) and electrospray ionization quadrupole ion trap mass spectrometry. Many metal‐coordinated complex ions were formed for cobalt and nickel: [2M+Met]2+, [3M+Met]2+, [M–H+Met]+, [2M–H+Met]+, [M+MetX]+, [2M+MetX]+ and [3M–H+Co]+, where M is the diol, Met is the metal used and X is the counter ion (acetate, chloride, nitrate). Copper showed the weakest formation of metal complexes with di‐exo‐2,3‐disubstituted trinorbornanediol yielding only the minor singly charged ions [M–H+Cu]+, [2M–H+Cu]+ and [2M+CuX]+. No clear differences were noted for cobalt complex formation, especially for cis‐2,3‐disubstituted isomers. However, 2,5‐disubstituted trinorbornanediols showed moderate diastereomeric differentiation because of the unidentate nature of the sterically more hindered exo‐isomer. trans‐Isomers gave rise to abundant [3M–H+Co]+ ion products, which may be considered a characteristic ion for bicyclo[221]heptane trans‐2,3‐ and trans‐2,5‐diols. To differentiate cis‐2,3‐isomers, the collision‐induced dissociation (CID) products for [3M+Co]2+, [M+CoOAc]+, [2M–H+Co]+ and [2M+CoOAc]+ cobalt complexes were investigated. The results of the CID of the monomeric and dimeric metal adduct complexes [M+CoOAc]+ and [2M–H+Co]+ were stereochemically controlled and could be used for stereochemical differentiation of the compounds investigated. In addition, the structures and relative energies of some complex ions were studied using hybrid density functional theory calculations. Copyright © 2009 John Wiley & Sons, Ltd.
Determination of mycotoxins in different food commodities by ultra‐high‐pressure liquid chromatography coupled to triple quadrupole mass spectrometry
Authors: Beltrán Eduardo , Ibáñez María , Sancho Juan Vicente , Hernández Félix
Published: May 2009

A rapid multianalyte‐multiclass method with little sample manipulation has been developed for the simultaneous determination of eleven mycotoxins in different food commodities by using ultra‐high‐pressure liquid chromatography coupled to triple quadrupole mass spectrometry (UHPLC/MS/MS). Toxins were extracted from the samples with acetonitrile/water (80:20, v/v) 0.1% HCOOH and, after a two‐fold dilution with water, directly injected into the system. Thanks to the fast high‐resolution separation of UHPLC, the eleven mycotoxins were separated by gradient elution in only 4 min. The method has been validated in three food matrices (maize kernels, dry pasta (wheat), and eight‐multicereal babyfood (wheat, maize, rice, oat, barley, rye, sorghum, millet)) at four different concentration levels. Satisfactory recoveries were obtained (70–110%) and precision (expressed as relative standard deviation) was typically below 15% with very few exceptions. Quantification of samples was carried out with matrix‐matched standards calibration. The lowest concentration successfully validated in sample was as low as 0.5 µg/kg for aflatoxins and ochratoxin A in babyfood, and 20 µg/kg for the rest of the selected mycotoxins in all matrices tested. Deoxynivalenol could be only validated at 200 µg/kg, due the poor sensitivity for this mycotoxin analysis. With only two exceptions (HT‐2 and deoxynivalenol), the limits of detection (LODs), estimated for a signal‐to‐noise ratio of 3 from the chromatograms of samples spiked at the lowest level validated, varied between 0.1 and 1 µg/kg in the three food matrices tested. The method was applied to the analysis of different kinds of samples. Positive findings were confirmed by acquiring two transitions (Q quantification, q confirmation) and evaluating the Q/q ratio. Copyright © 2009 John Wiley & Sons, Ltd.
Characterization of metabolites in rat plasma after intravenous administration of salvianolic acid A by liquid chromatography/time‐of‐flight mass spectrometry and liquid chromatography/ion trap mass spectrometry
Authors: Shen Yi , Wang Xueyan , Xu Lihua , Liu Xiaowei , Chao Ruobing
Published: May 2009

Salvianolic acid A (SalA) is one of the main active constituents in Salvia miltiorrhiza (Danshen). Although the pharmacokinetics of SalA in rats after intravenous (i.v.) administration of Danshen injection has been reported, the information relevant to the metabolites of SalA in vivo is absent so far. In this study, by means of liquid chromatography with time‐of‐flight mass spectrometry (LC/TOFMS) and liquid chromatography with ion trap mass spectrometry (LC/MSn) techniques, the unknown metabolites of SalA in rat plasma after i.v. administration of the purified SalA at the dose of 20 mg/kg body weight were identified. A liquid‐liquid extraction method was established to separate the metabolites from the plasma and the chromatographic separations were performed on a Xterra MS C18 column (100 mm × 4.6 mm i.d., 3.5 µm) with acetonitrile/methanol/water/formic acid (20.5:19.5:64: 0.05, v/v/v/v) as the mobile phase at a constant flow rate of 0.2 mL/min. Based on the data obtained from the LC/TOFMS determination (the total ion chromatograms, MS spectra and extracted ion chromatograms), in combination with the characteristic fragment ions acquired from the LC/MSn determination, five metabolites were identified as SalA‐monoglucuronide, monomethyl‐SalA‐monoglucuronide, mono‐methyl‐SalA, dimethyl‐SalA and dimethyl‐SalA‐monoglucuronide, and the possible chemical structures were deduced. The results indicated that SalA might mainly undergo two metabolic pathways in vivo in rats, which were methylation and glucuronidation. The present studies have laid a solid foundation for the metabolic mechanism of SalA in vivo. Copyright © 2009 John Wiley & Sons, Ltd.
Toxicity Assessments of Multisized Gold and Silver Nanoparticles in Zebrafish Embryos
Authors: Bar‐Ilan Ofek , Albrecht Ralph M. , Fako Valerie E. , Furgeson Darin Y.
Published: May 2009

The potential toxicity of nanoparticles is addressed by utilizing a putative attractive model in developmental biology and genetics: the zebrafish (Danio rerio). Transparent zebrafish embryos, possessing a high degree of homology to the human genome, offer an economically feasible, medium‐througput screening platform for noninvasive real‐time assessments of toxicity. Using colloidal silver (cAg) and gold nanoparticles (cAu) in a panoply of sizes (3, 10, 50, and 100 nm) and a semiquantitative scoring system, it is found that cAg produces almost 100% mortality at 120 h post‐fertilization, while cAu produces less than 3% mortality at the same time point. Furthermore, while cAu induces minimal sublethal toxic effects, cAg treatments generate a variety of embryonic morphological malformations. Both cAg and cAu are taken up by the embryos and control experiments, suggesting that cAg toxicity is caused by the nanoparticles themselves or Ag+ that is formed during in vivo nanoparticle destabilization. Although cAg toxicity is slightly size dependent at certain concentrations and time points, the most striking result is that parallel sizes of cAg and cAu induce significantly different toxic profiles, with the former being toxic and the latter being inert in all exposed sizes. Therefore, it is proposed that nanoparticle chemistry is as, if not more, important than specific nanosizes at inducing toxicity in vivo. Ultimately such assessments using the zebrafish embryo model should lead to the identification of nanomaterial characteristics that afford minimal or no toxicity and guide more rational designs of materials on the nanoscale.
The determination of resudual alcohol in defatted alcohol washed soybean flakes
Authors: Black L. T. , Kirk L. D. , Mustakas G. C.
Published: May 2009

A method is deseribed for determination of residual alcohol in soybean flakes washed with aqueous alcohol and desolventized to prepare a high‐protein food supplement. Theamount of alcohol removed from the flakes by extraction with acetone is determined quantitatively by esterification with phthalic anhydride. An excess of reagent is required since water, present in the sample causes a secondary reaction which consumes phthalic anhydride. This analysis has been applied to flakes containing from 0.2 to 10% of methanol, ethanol, or isopropanol. Accuracy of the method was established by adding known amounts of the three alcohols to soybean flakes. A relative error of less than 1% was obtained with a standard derivation of 0.05%.
X‐ray powder diffraction data on salts of ॅ‐sulfonated long chain acids
Authors: Lutz D. A. , Weil J. K. , Stirton A. J. , Witnauer L. P.
Published: May 2009

This paper reports x‐ray powder diffraction study for twentyfour salts of ॅ‐sulfonated normal long chain fatty acids. Acid and neutral sodium, potassium lithium, cesium, calcium, magnesium, and triethanolammonium salts of ॅ‐sulfolauric, myristic, palmitic, stearic, and behenic acids were examined. The method can be used to identify and distinguish the individual salts and has possible application to the analysis of mixtures.
Properties of oil extracted from cottonseed with acetone‐hexane‐water solvent mixture
Authors: King Whlliam H. , Frampton Vernon L.
Published: May 2009

Slightly more neutral oil was obtained on the exhaustive extraction of raw cottonseed meats with the acetone‐hexanewater (AHW) solvent mixture than was obtained under the same conditions with commerical hexane. Although most of the gossypol originally present in the seed is extracted with the oil when the AHW solvent mixture is used, the crude oils refined and bleached to yield oils of excellent colors. Methods of recovery of the solvent from the mixed solvent miscellas are reported, together with the refining and bleaching data for the recovered oils.
Chemical and physical characteristics and possible configuration of toxins from tung kernels
Authors: Holmes R. L. , O'Connor Robert T.
Published: May 2009

Based on limited chemical and physical data, including the infrared and ultraviolet spectra of the toxins and their saponification products, it is suggested that Tung Toxin I and Tung Toxin II are diesters of a 2,3‐unsaturated‐5‐keto acid, a polyhydroxy acid and a 3,4‐unsaturated‐5‐keto tertiary alcohol. The 2,3‐unsaturated‐5‐keto acid is assumed to be in equilibrium with its enol tautomer, the keto form possessing a conjugated diene and the enol form a conjugated triene structure. The polyhydroxy acid is probably very similar to gluconic acid.
Production of linolenic acid from linseed oil
Authors: Beal R. E. , Sohns V. E. , Eisenhauer R. A. , Griffin E. L.
Published: May 2009

Linolenic acid of more than 95% purity was produced by liquid‐liquid extraction of linseed oil fatty acids with wet furfural and hexane in a Podbielniak centrifugal extractor. The minimum ratio of furfural to linseed acids to obtain this purity was 10 to 1. There was no significant change in product purity for solvent ratios between 10 and 15, operating temperatures from 90Ŷ to 110ŶF., and furfural moisture contents between 1.0 and 2.8%. When the solvent ratio is reduced to 8 or the furfural moisture to 0.2%, purity decreases. Oxidation of linseed acids before extraction also results in decreased separation. An estimate based on pilotplant data indicates a 舠cost to make舡 (excluding administrative and selling expenses, profit, income taxes, and interest on investment) of 18.0 cents per pound of 97% linolenic acid for a process which includes hydrolyzing linseed oil, separating the fatty acids by liquid‐liquid extraction, recovering solvents by distillation, and distilling the fatty acid products. Potential uses for linolenic acid are reviewed.
Invasive species management in two‐patch environments: agricultural damage control in the raccoon (Procyon lotor) problem, Hokkaido, Japan
Authors: Kotani Koji , Ishii Hiromasa , Matsuda Hiroyuki , Ikeda Tohru
Published: May 2009

We develop discrete‐time models for analyzing the long‐run equilibrium outcomes on invasive species management in two‐patch environments with migration. In particular, the focus is on a situation where removal operations for invasive species are implemented only in one patch (controlled patch). The new features of the model are that (1) asymmetry in density‐dependent migration is considered, which may originate from impact of harvesting as well as heterogeneous habitat conditions, and (2) the effect of density‐dependent catchability accounts for the fact that the required effort level to remove one individual may rise as the existing population decreases. The model is applied to agricultural damage control in the raccoon (Procyon lotor) problem that has occurred in Hokkaido, Japan. Numerical illustrations demonstrate that the long‐run equilibrium outcomes largely depend on the degree of asymmetry in migration as well as the sensitivity of catchability in response to a change in the population size of the invasive species. Furthermore, we characterize the conditions under which the economically optimal effort levels are qualitatively affected by the above two factors, and conclude that aiming at local extermination of invasive species in the controlled patch is justified.
Modelling mate‐finding Allee effects and populations dynamics, with applications in pest control
Authors: Boukal David S. , Berec Luděk
Published: May 2009

In this paper, we review how mate‐finding Allee effects enter population dynamical models that consider both sexes, highlight possible limitations of the more widely used “one‐sex” models, and outline the links between the different model classes. We further explore interactions between the mate‐finding Allee effect and other mechanisms relevant to pest‐control strategies: release of natural enemies, sterile male release, and culling. Many of these strategies impose an additional component Allee effect on the population, and we discuss which of them might be efficient in the control of pest species that also suffer from the failure to locate mates. We focus primarily on eradication thresholds; our simple models show that most of the strategies yield similar results, and depending on the costs, one strategy or a combination of several can lead to the most efficient control.