bluuebunny/crossref_metadata_2025 huggingface dataset:
Haplotype association analysis for late onset diseases using nuclear family data
Authors: Li Chun , Boehnke Michael
Published: February 2006

In haplotype‐based association studies for late onset diseases, one attractive design is to use available unaffected spouses as controls (Valle et al. [1998] Diab. Care 21:949–958). Given cases and spouses only, the standard expectation‐maximization (EM) algorithm (Dempster et al. [1977] J. R. Stat. Soc. B 39:1–38) for case‐control data can be used to estimate haplotype frequencies. But often we will have offspring for at least some of the spouse pairs, and offspring genotypes provide additional information about the haplotypes of the parents. Existing methods may either ignore the offspring information, or reconstruct haplotypes for the subjects using offspring information and discard data from those whose haplotypes cannot be reconstructed with high confidence. Neither of these approaches is efficient, and the latter approach may also be biased. For case‐control data with some subjects forming spouse pairs and offspring genotypes available for some spouse pairs or individuals, we propose a unified, likelihood‐based method of haplotype inference. The method makes use of available offspring genotype information to apportion ambiguous haplotypes for the subjects. For subjects without offspring genotype information, haplotypes are apportioned as in the standard EM algorithm for case‐control data. Our method enables efficient haplotype frequency estimation using an EM algorithm and supports probabilistic haplotype reconstruction with the probability calculated based on the whole sample. We describe likelihood ratio and permutation tests to test for disease‐haplotype association, and describe three test statistics that are potentially useful for detecting such an association. Genet. Epidemiol. 2006. © 2006 Wiley‐Liss, Inc.
Self‐reported health: reliability and consequences for health inequality measurement
Authors: Clarke Philip M. , Ryan Chris
Published: February 2006

Self‐reported health (SRH) is one of the most frequently employed measures for assessing income‐related health inequalities between counties. A previous study has shown that 28% of respondents changed their assessment of their health status when asked a SRH question on two occasions in the same survey (first as part of self‐completed questionnaire and then in a personal interview). This study re‐examines this issue using another survey where SRH was again asked twice of respondents, but this time the personal interview was first and self‐completion second. We find the same variation in responses, but the predominant direction is away from the ‘extreme’ categories ‘Excellent’ and ‘Poor’ which is the opposite direction to the previous study. We therefore conclude that the most likely explanation is a mode of administration effect that makes people less likely to choose the extreme categories in a self‐completion questionnaire, but not a personal interview. However, this effect has a relatively minor impact on measures of inequality. This is due to a large proportion of the movement (i.e. movement to the middle) not being related to income and hence does not systematically impact on the cumulative distribution of health across this measure of socio‐economic status. Copyright © 2006 John Wiley & Sons, Ltd.
Who does the hat fit? Teenager heterogeneity and the effectiveness of information policies in preventing cannabis use and heavy drinking
Authors: Etilé Fabrice
Published: February 2006

This paper models heterogeneity in the relationship between exposure to information at school or in the media and cannabis use and heavy drinking, using latent class techniques applied to data on French teenagers collected in 1993. Teenagers cluster in five classes which differ in their tastes for drunkenness and cannabis, and in the correlations between information exposure and cannabis use or heavy drinking. Teenager heterogeneity and habit‐formation or precociousness effects limit the effectiveness of general information policies. Improving the impact of prevention requires that interventions be better targeted and personalised. We show how economic theory, latent class techniques and existing psychometric questionnaires can be used to build simple statistical tools for targeting prevention policies. Copyright © 2006 John Wiley & Sons, Ltd.
Vascular perfusion of human lung cancer in a rat orthotopic model using dynamic contrast‐enhanced magnetic resonance imaging
Authors: Rosen Yael , Ramniceanu Gregory , Margalit Raanan , Grobgeld Dov , Eilam Raya , Degani Hadassa , Furman‐Haran Edna
Published: February 2006

Lung cancer is the leading cause of death among cancers. Early detection and diagnosis present a major goal in the efforts to improve survival rates of lung cancer patients. Changes in angiogenic activity and microvascular perfusion properties in cancers can serve as markers of malignancy. The aim of this study was to employ MRI means to measure the microvascular perfusion parameters of orthotopic nonsmall cell lung cancer, using the experimental rat model. Anatomical and dynamic contrast‐enhanced lung images were acquired at high spatial resolution, and registered and analyzed, pixel by pixel and globally, by means of a model‐based algorithm. The MRI output yielded color‐coded parametric images of the influx and efflux transcapillary transfer constants that indicated rapid microvascular perfusion. The transfer constants were about 1 order of magnitude higher than those found in other tumors or in nonorthotopic lung cancer, with the influx constant median value of 0.42 min−1 and the efflux constant median value of 1.61 min−1. The rapid perfusion was in accord with the immunostaining of the capillaries, which suggested the tumor exploitation of the existing alveolar vessels. The results showed that high resolution, dynamic, contrast‐enhanced MRI is an effective tool for the quantitative measurement of spatial and temporal changes in lung cancer perfusion and vasculature. © 2006 Wiley‐Liss, Inc.
TGF‐β1 immobilized tri‐co‐polymer for articular cartilage tissue engineering
Authors: Chou Cheng‐Hung , Cheng Winston T. K. , Lin Chien‐Cheng , Chang Chih‐Hung , Tsai Chien‐Chen , Lin Feng‐Huei
Published: February 2006

Tri‐co‐polymer with composition of gelatin, hyaluronic acid and chondroitin‐6‐sulfate has been used to mimic the cartilage extracellular matrix as scaffold for cartilage tissue engineering. In this study, we try to immobilize TGF‐β1 onto the surface of the tri‐co‐polymer sponge to suppress the undesired differentiation during the cartilage growth in vitro. The scaffold was synthesized with a pore size in a range of 300–500 μm. TGF‐β1 was immobilized on the surface of the tri‐co‐polymer scaffold with 1‐ethyl‐3‐(3‐dimethylaminopropyl) carbodiimid (EDC) as a crosslinking agent. Tri‐co‐polymer scaffolds with and without TGF‐β1 were seeded with porcine chondrocytes and cultured in a spinner flask for 2, 4, and 6 weeks. The chondrocytes were characterized by the methods of immunohistochemical staining with anti‐type II collagen and anti‐S‐100 protein monoclonal antibody, and RT‐PCR. After culturing for 4 weeks, chondrocytes showed positive in S‐100 protein, Alcian blue, and type II collagen for the scaffold with TGF‐β1 immobilization. There is no observed type I and type X collagen expression in the scaffolds from the observation of RT‐PCR. In addition, the scaffold without TGF‐β1 immobilization, type X collagen, can be detected after cultured for 2 weeks. Type I collagen was progressively expressed after 4 weeks. These results can conclude that TGF‐β1 immobilized scaffold can suppress chondrocytes toward prehypertrophic chondrocytes and osteolineage cells. The tri‐co‐polymer sponge with TGF‐β1 immobilization should have a great potential in cartilage tissue engineering in the future. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2006
Three‐dimensional printing of porous polyethylene structure using water‐based binders
Authors: Suwanprateeb J. , Chumnanklang R.
Published: February 2006

This study demonstrated a freeform fabrication of porous hydrophobic polyethylene parts by three‐dimensional printing technique, using water‐based binder. This involved initially making a green structure by printing a binder onto the mixture of polyethylene and water soluble adhesive powder bed. The green structure was thermal treated to melt polyethylene fraction to achieve a well‐connected structure within the part. Adhesive components were then leached out in water, leaving only porous structure of polyethylene. Specimens with ratios of polyethylene to adhesive from 80:20 to 20:80 were fabricated and characterized. It was found that increasing polyethylene content increased density, modulus, and strength while decreased porosity. Preliminary in vitro toxicity test of porous parts using L929 cells showed that the cells that were in contact with samples were healthy. No inhibition zone was observed. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2006
Relationship between fracture toughness and flexural strength in dental porcelains
Authors: Cesar Paulo Francisco , Yoshimura Humberto Naoyuki , Miranda Walter Gomes , Miyazaki Caroline Lumi , Muta Luciana Mayumi , Filho Leondardo Eloy Rodrigues
Published: February 2006

The aim of this study was to investigate the correlation between fracture toughness (KIc) and flexural strength (FS) in dental porcelains. Porcelains with different leucite contents and clinical indications were used (A, B, C, D, and E). KIc was determined by surface crack in flexure method (SCF) and FS was determined by four‐point‐bending test. Microstructural characterization was also carried out. The leucite contents of porcelains A, B, C, D, and E were, respectively, 22, 22, 6, 15, and 0%. Materials with higher leucite content (A and B) presented significantly higher KIc values compared to materials with lower leucite content (C and E). The Weibull moduli (m) of porcelains A and B were statistically higher than those of the other three materials. Regarding characteristic strength (σ0), porcelains D and E showed similar values and statistically higher than those of the other materials which were statistically different from each other. According to the regression analysis, σ0 increased with the increase of KIc until ∼0.75 MPa m1/2. After that, the increase in KIc was accompanied by a decrease in σ0. However, the Weibull modulus increased with the increase in KIc, especially for values greater than 0.80 MPa m1/2. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2006
Reduction in dentin permeability using a slurry containing dicalcium phosphate and calcium hydroxide
Authors: Cherng Aishuan Maria , Takagi Shozo , Chow Laurence
Published: February 2006

Treatments that obdurate dentin tubules have been used for reducing dentin hypersensitivity. The purpose of this study was to determine the effect of a treatment with a slurry of micron sized calcium phosphate on the hydraulic conductance (Lp) of etched dentin discs in vitro. The treatment slurry was prepared by mixing a powder mixture of dicalcium phosphate anhydrous and calcium hydroxide with a solution that contained sodium fluoride and carboxymethyl cellulose. The mean baseline Lp (in mL cm−2 s–1 H2O cm–1) was 2.07 ± 1.45 (mean ± SD; n = 13)). After one treatment and 2, 4, and 7 days of incubation in a protein‐free saliva‐like solution (SLS), the mean relative Lp, presented as % of baseline, were 65 ± 16, 42 ± 27, 36 ± 26, and 33 ± 27 (n = 13), respectively. The Lp values of the baseline and treatment after incubation in the SLS were significantly (p < 0.05) different. Scanning electron microscopic examination showed partial obturation of dentin tubules in the treated dentin. X‐ray diffraction and chemical analyses indicated the major product formed from the slurry was a fluoride‐containing hydroxyapatite. Treatment appeared effective in further reducing Lp of dentin discs after incubation in the SLS. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2006
Critical comparison of two methods for the determination of nanomechanical properties of a material: Application to synthetic and natural biomaterials
Authors: Lewis Gladius , Xu Jie , Dunne Nicholas , Daly Catherine , Orr John
Published: February 2006

Two methods used for determining the elastic modulus (E) and hardness (H) of a material—the original version of the well‐known Oliver‐Pharr Method, OOPM, and a variant of it called the Modified Slopes Method, MSM—were critically compared. The nanoindentation test results, of indenter load‐versus‐indenter displacement, were recorded for six series of specimens, three of commercially‐available acrylic bone cements (Palacos® R and Cemex® XL) and three of bones (human, bovine, and mouse). In the first series, the specimens were prepared from Palacos® R cement mantles retrieved from cemented total hip joint replacements after 11 months, 11 years, and 21 years in vivo. In the second and third series, the specimens were fabricated from hand‐ and vacuum‐mixed dough of Cemex XL® cement, respectively. In the fourth, fifth, and sixth series, the specimens were prepared from fresh frozen cortical bone of human tibia, plexiform bone from fresh bovine tibia, and femora from inbred mice, respectively. It was found that, for a given material, the values of E or H computed using OOPM and MSM are not significantly different. However, the recommendation is that MSM is preferable because it is straightforward—only the nanoindentation measurements and values of constants that depend on the geometry of the indenter used are needed. In contrast, when the OOPM is used, there is a critical input (the indenter tip area function), whose computation is problematic. The article also includes a succinct discussion of factors that affect the values of material properties computed from nanoindentation measurements, such as the loading rate and the surface roughness of the test specimen. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2006
Pulsatile dynamic stiffness of cartilage‐like materials and use of agarose gels to validate mechanical methods and models
Authors: Scandiucci de Freitas P. , Wirz D. , Stolz M. , Göpfert B. , Friederich N.‐F. , Daniels A. U.
Published: February 2006

Stiffness is a fundamental indicator of the functional state of articular cartilage. Reported test modes include compressive incremental strain to determine the equilibrium modulus, and sinusoidal strain to determine the dynamic modulus and stress/strain loss angle. Here, initial development is described for a method recognizing that gait is pulsatile. Agarose gels have been used by others for validation or comparison of mechanical test methods and models for cartilage and proteoglycan aggregate. Accordingly, gels ranging from 0.5 to 20% agarose were prepared. Pulsatile stiffness in both indentation and unconfined compression were closely reproducible. Stiffness as a function of agarose concentration rose exponentially, as found using other methods. Indentation stiffness was higher than for unconfined compression and ranged from ∼2.0 kPa for 0.5% gel to ∼3800 kPa for 20% gel. Pulsatile dynamic stiffness appears to be a useful method, although further development is needed. Agarose gel stiffness values obtained by other methods were reviewed for comparison. Unfortunately, reported values for a given agarose concentration ranged widely (e.g. fourfold) even when test methods were similar. Causes appear to include differences in molecular weight and gel preparation time–temperature regimens. Also, agarose is hygroscopic, leading to unintended variations in gel composition. Agarose gels are problematic materials for validation or comparison of cartilage mechanical test methods and models. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2006
Multivariate analysis of surface physico‐chemical properties controlling biofilm formation on orthodontic adhesives prior to and after fluoride and chlorhexidine treatment
Authors: Chin Mervyn Y. H. , Sandham Andrew , Pratten Jonathan , Joop De Vries  , van der Mei Henny C. , Busscher Henk J.
Published: February 2006

Biofilm formation on orthodontic adhesives is a serious clinical problem, as it leads to enamel demineralization around fixed orthodontic appliances, often leaving white spot lesions after their removal. The aim of this work was to determine the influence of surface physico‐chemical properties of four commonly used orthodontic adhesives (Concise™, Fuji ORTHO™ LC, Ketac Cem μ, and Transbond™ XT) on early bacterial biofilm formation. In addition, effects of two commercially available mouthrinses (0.05% sodium fluoride and 0.2% chlorhexidine gluconate) on these properties and biofilm formation were determined. Water contact angles on the adhesives decreased after fluoride and chlorhexidine treatment, concurrent with an increase in carbon and a decrease in oxygen surface concentrations, except for Transbond, as determined by X‐ray photoelectron spectroscopy. No fluorine was detected on any of the adhesive surfaces after fluoride treatment, while all surfaces showed chlorine after chlorhexidine treatment. Surface roughness of the adhesives measured using three‐dimensional optical profilometry was around 4 μm and found not to be a factor governing early biofilm formation. Multiple linear regression analysis indicated that early biofilm formation by Streptococcus sanguis could be explained in a model comprising hydrophobicity and the prevalence of oxygen‐ and nitrogen‐rich components on the adhesive surfaces. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2006
Biodegradable polymer–silica xerogel composite microspheres for controlled release of gentamicin
Authors: Xue J.M. , Tan C.H. , Lukito D.
Published: February 2006

Single and double layered composite microspheres were prepared by encapsulating gentamicin‐loaded silica xerogels with biodegradable PLGA polymers (poly(DL‐lactide‐co‐glycolide)). The in vitro drug release properties of both the composite microspheres were investigated. The single layered composite microspheres showed a high initial burst, followed by two sustained release stages lasting for ∼6 weeks. The two sustained release stages of the single layered composite microspheres could be attributed to the swelling and bulk erosion of the polymer encapsulations, respectively. In comparison with the single layered composite microspheres, the double layered composite microspheres realized a much reduced initial burst together with three sustained release stages. The whole release period of the double layered composite microspheres could last more than 9 weeks. These distinct behaviors make the double layered composite microspheres promising as a new drug release material for localized drug delivery applications. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2006
Behavior of human osteoblast‐like cells in contact with electrodeposited calcium phosphate coatings
Authors: Richard D. , Dumelié N. , Benhayoune H. , Bouthors S. , Guillaume C. , Lalun N. , Balossier G. , Laurent‐Maquin D.
Published: February 2006

Calcium‐deficient hydroxyapatite (Ca‐def‐HAP) thin films were elaborated on Ti6Al4V substrates by electrodeposition. The coatings exhibit two different morphologies and crystallinities. Human osteoblast‐like cells (MG‐63) were cultured on the surfaces of these materials; the cell content and viability were evaluated up to 28 days. The scanning electron microscopy and biological investigations showed cells with a normal morphology, good proliferation, and viability from 7 to 21 days. But after 28 days, the number of live cells decreases in both cases; however, this decrease is less important in the case of calcium phosphate (CaP) coating surface when compared with the control (cell culture plastic). The cells cultured on Ca‐def‐HAP coating exhibit more cellular extensions and extracellular matrix. RT‐PCR for type I collagen, alkaline phosphatase, and osteocalcin studies were also carried out, and was found that the CaP enhances gene expression of ALP and OC and thus the differentiation of osteoblast‐like cells. Moreover, this study shows that the difference in the morphology of CaP coatings has no effect on the biocompatibility. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2006
Are calculated enthalpies of formation sometimes more reliable than experimental? A test on alkyl substituted benzoic acids
Authors: Böhm Stanislav , Exner Otto
Published: February 2006

Energies of 20 alkyl‐substituted benzoic acids were calculated at the levels B3LYP/6‐311+G(d,p)//B3LYP/6‐311+G(d,p) and MP2/6‐311+G(d,p)//MP2/6‐311+G(d,p); the pertinent enthalpies at 298 K were calculated at the same levels. Comparison with experimental enthalpies of formation ΔfH°g(298) was carried out in terms of isodesmic reactions, that is, in the relative values. Of the four calculated quantities, the DFT enthalpies yielded best correlation with the standard deviation of 2.1 kJ mol−1, near to the experimental uncertainty; the DFT energies are only slightly worse and the MP2 enthalpies or energies much worse. However, the DFT method overestimated systematically the substituent effects and had to be calibrated. Comparison with the experimental gas‐phase acidities was less telling and the fit was worse because both methods overestimated the substituent effects. Extending the base in selected examples did not give better results. Although the systematic deviations are evidently due to the imperfections of the theoretical models, individual big deviations should be attributed to experimental errors or to the abnormal behavior of certain compounds at the experimental conditions. From this point of view, three examples of the so‐called long‐range effect claimed in the case of different benzoic acid derivatives, always for substituents in the meta position, must be refused as unproven because the experimental energies were not confirmed by calculations. © 2006 Wiley Periodicals, Inc. J Comput Chem 5: 571–577, 2006
An orbital localization criterion based on the theory of “fuzzy” atoms
Authors: Alcoba Diego R. , Lain Luis , Torre Alicia , Bochicchio Roberto C.
Published: February 2006

This work proposes a new procedure for localizing molecular and natural orbitals. The localization criterion presented here is based on the partitioning of the overlap matrix into atomic contributions within the theory of “fuzzy” atoms. Our approach has several advantages over other schemes: it is computationally inexpensive, preserves the σ/π‐separability in planar systems and provides a straightforward interpretation of the resulting orbitals in terms of their localization indices and atomic occupancies. The corresponding algorithm has been implemented and its efficiency tested on selected molecular systems. © 2006 Wiley Periodicals, Inc. J Comput Chem 27: 596–608, 2006
Identification of the four most common β‐globin gene mutations in Greek β‐thalassemic patients and carriers by PCR‐SSCP: advantages and limitations of the method
Authors: Kakavas Konstantinos V. , Noulas Argiris , Chalkias Christos , Hadjichristodoulou Christos , Georgiou Ioannis , Georgatsou Elena , Bonanou Sophia
Published: February 2006

In the present study we investigated whether the single‐strand conformational polymorphism (SSCP) method could be employed to identify (rather than simply detect) the four most common β‐globin gene mutations in the Greek population: IVS‐I‐110, Cd39, IVS‐I‐1, and IVS‐I‐6. Using DNA from 50 β‐thalassemic patients and carriers, we amplified by PCR the appropriate 238‐bp region of the human β‐globin gene, analyzed the reaction products by nondenaturing polyacrylamide gel electrophoresis, and visualized the bands by silver staining. Single‐stranded DNA (ssDNA) fragments showed a reproducible pattern of bands that was characteristic of the mutations present. With the use of control samples containing six of the 10 possible combinations of the four most common β‐globin gene mutations, we were able to predict the mutations present in a quarter of the patients studied. Our predictions were confirmed independently by the amplification refractory mutation system (ARMS) method. We conclude that this non‐radioactive PCR‐SSCP method can be used to reliably identify mutations in patients, provided that suitable controls are available. Moreover, the method is easy to apply to the identification of mutations in carriers, which makes it particularly useful for population screening. J. Clin. Lab. Anal. 20:1–7, 2006. © 2006 Wiley‐Liss, Inc.
Diagnosis of Chlamydia trachomatis infection
Authors: Mania‐Pramanik Jayanti , Potdar Shobha , Kerkar Shilpa
Published: February 2006

Important progress in the diagnosis of Chlamydia trachomatis (C. trachomatis) includes the development of nucleic acid amplification techniques such as polymerase chain reaction (PCR) and ligase chain reaction (LCR). Commercial kits are available, but they are costly, sporadic in availability, must be imported, and are economically beyond the reach of common people. To overcome this limitation, most research laboratories have standardized their in‐house‐developed PCR methods for diagnosing this infection. However, each laboratory has to spend a great deal of time and money to accomplish this. Published reports do not always elaborate the steps involved in standardizing a test so that it can immediately be reproduced in another setting. In the present study we attempted to elaborate the steps involved in standardizing a sensitive and specific PCR technique followed by hybridization with specific C. trachomatis probe to diagnose this infection in cervical, introital, and urine specimens, and used it to determine the infection rate in a clinical population. J. Clin. Lab. Anal. 20:8–14, 2006. © 2006 Wiley‐Liss, Inc.
Use of a new silica clotting time for diagnosing lupus anticoagulant in patients who meet the clinical criteria for antiphospholipid syndrome
Authors: Grypiotis Panagiotis , Ruffatti Amelia , Pengo Vittorio , Tonello Marta , Biasiolo Alessandra , Zamboni Daniela , Cavazzana Anna , Todesco Silvano
Published: February 2006

The silica clotting time (SCT) is a phospholipid‐dependent coagulation assay used for the laboratory diagnosis of lupus anticoagulant (LA) antibodies. The sensitivity and specificity of a new commercial SCT for identifying LA in patients who meet the clinical criteria for antiphospholipid syndrome (APS), and its association with thrombotic events were evaluated here. Forty‐five patients who met the clinical criteria for APS according to the Sapporo International Consensus Statement were examined. Sixty‐nine patients who did not meet the clinical criteria for APS, and 20 blood donors were used as controls. Plasma samples from the patients and controls were tested for LA using a new commercial SCT with low and high synthetic phospholipid concentrations. The results were compared with those obtained by diluted Russell's viper venom time (dRVVT) and activated partial thromboplastin time (APTT). SCT's sensitivity for identifying LA in patients who met the clinical criteria of APS was higher compared to APTT and dRVVT (53.3% vs. 31.1% and 31.1%), and the specificities of these assays were 96.6%, 100%, and 98.9%, respectively. When dRVVT was combined with SCT, and dRVVT was combined with APTT their sensitivities were 57.7% and 48.8%, and their specificities were 96.6% and 98.9%, respectively. A stepwise logistic regression analysis indicated that the combination of dRVVT with SCT was associated with total thrombotic events (odds ratio (OR)=11.5, 95% confidence interval (CI)=1.25–106.3, P=0.031) as well as with venous thrombosis (OR=4.09, 95% CI=1.16–14.43, P=0.028). According to our results, SCT is the most sensitive assay for identifying LA in patients who meet the clinical criteria for APS. Moreover, the highest sensitivity was reached with a combination of SCT and dRVVT. The method's association with total thrombotic events and venous thrombosis was in fact significant. J. Clin. Lab. Anal. 20:15–18, 2006. © 2006 Wiley‐Liss, Inc.
Predictive value of the serum level of N‐terminal pro‐brain natriuretic peptide and high‐sensitivity C‐reactive protein in left ventricular remodeling after acute myocardial infarction
Authors: Xiaozhou Hu , Jie Zhang , Zhenrong Li , Liyan Cui
Published: February 2006

This study was designed to measure the correlation between left ventricular (LV) remodeling 3 months after successful reperfusion therapy, and the levels of serum N‐terminal pro‐brain natriuretic peptide (NT‐proBNP) and high‐sensitivity C‐reactive protein (hs‐CRP) at 3 days after acute myocardial infarction (AMI), and to determine the predictive levels of NT‐proBNP and hs‐CRP for LV remodeling. A total of 106 patients with first AMI were included in this study. Each patient was examined by echocardiography (ECG) on the third day and third month after AMI, and LV remodeling was determined by the difference in the LEV end‐diastolic volume (LVEDV) between the third day and the third month. Serum NT‐proBNP and hs‐CRP level were measured 3 days after AMI. Then the correlation between the 3‐months change in LVEDV and the levels of serum NT‐proBNP or hs‐CRP was determined. In addition, sensitivity and specificity were calculated with a receiver operating characteristic (ROC) curve to identify correspondence with LV remodeling (defined as the change rate of LVEDV >20%). Our results showed that the correlation coefficients with the change of LVEDV were 0.706 for serum NT‐pro BNP (P<0.001) and 0.596 for hs‐CRP (P<0.05). With a cutoff value of 0.2, the area under the ROC curve (AUC) was 0.894 for NT‐proBNP and 0.825 for hs‐CRP. Although the AUC did not statistically differ between NT‐proBNP and hs‐CRP, NT‐proBNP is more effective than serum hs‐CRP as a marker to predict LV remodeling. J. Clin. Lab. Anal. 20:19–22, 2006. © 2006 Wiley‐Liss, Inc.
Mutation analysis of Crouzon syndrome in Taiwanese patients
Authors: Chang Chin‐Ping , Wan Lei , Tsai Chang‐Hai , Lee Cheng‐Chun , Tsai Fuu‐Jen
Published: February 2006

Crouzon syndrome is an autosomal‐dominant disorder that causes premature fusion of the cranial suture. Crouzon, Pfeiffer, and Apert syndromes are caused by mutations in the extracellular, third immunoglobulin‐like domain, and adjacent linker regions (exons IIIa and IIIc) of the fibroblast growth factor receptor 2 (FGFR2) gene. We screened 12 Crouzon syndrome patients for mutations in exons IIIa and IIIc of the FGFR2 gene by polymerase chain reaction (PCR) and direct sequencing. Mutations were detected in nine of 12 patients at amino acid positions 278, 281, 289, 342, and 354. More than half of the studied Crouzon patients carried a mutation resulting in either the loss or gain of a cysteine residue. A novel missense Ser354Phe substitution at exon IIIc of the human FGFR2 gene was found. According to our results, sequencing analysis of IgIII domain of the FGFR2 gene can lead to a genetic diagnosis of Crouzon syndrome. J. Clin. Lab. Anal. 20:23–26, 2006. © 2006 Wiley‐Liss, Inc.
The mechanisms of change in the treatment of borderline personality disorder with transference focused psychotherapy
Authors: Levy Kenneth N. , Clarkin John F. , Yeomans Frank E. , Scott Lori N. , Wasserman Rachel H. , Kernberg Otto F.
Published: February 2006

We address how Transference Focused Psychotherapy (TFP) conceptualizes mechanisms in the cause and maintenance of borderline personality disorder (BPD) as well as change mechanisms both within the patient and in terms of specific therapists' interventions that engender patient change. Mechanisms of change at the level of the patient involve the integration of polarized representations of self and others; mechanisms of change at the level of the therapist's interventions include the structured treatment approach and the use of clarification, confrontation, and “transference” interpretations in the here and now of the therapeutic relationship. In addition, we briefly review evidence from our group regarding the following hypothesized mechanisms of change: contract setting, integration of representations, and changes in reflective functioning (RF) and affect regulation. © 2006 Wiley Periodicals, Inc. J Clin Psychol 62: 481–501, 2006.
Interpersonal psychotherapy for borderline personality disorder: Possible mechanisms of change
Authors: Markowitz John C. , Skodol Andrew E. , Bleiberg Kathryn
Published: February 2006

This article describes the rationale for applying interpersonal psychotherapy (IPT) to the treatment of patients who have borderline personality disorder and explains the adaptation of standard IPT to that end. The authors describe the preliminary stages of adapting IPT for a pilot study to test its feasibility and potential efficacy and speculate on potentially therapeutic mechanisms for IPT in treating patients who have borderline personality disorder. © 2006 Wiley Periodicals, Inc. J Clin Psychol 62: 431–444, 2006.
Semiquantitative analysis of isomeric oligosaccharides by negative‐ion mode UV‐MALDI TOF postsource decay mass spectrometry and their fragmentation mechanism study at N‐acetyl hexosamine moiety
Authors: Yamagaki Tohru , Suzuki Hiroaki , Tachibana Kazuo
Published: February 2006

Postsource decay (PSD) spectra of isomeric neutral lactooligosaccharide mixtures were measured from the chlorinated molecules [M + Cl]− by negative‐ion mode ultraviolet matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry (UV‐MALDI TOF MS) to estimate quantitatively the mixing ratios in their mixtures. The PSD ions specific to each isomeric structure were used to distinguish the linkage and branching isomers, and the molar ratios of the isomers were estimated from their ion abundances. The relative ion abundances changed linearly in the PSD spectra of the mixtures of the isomers as their molar ratio was varied in the analyte solutions. Therefore, the molar ratios of the isomers in the analyte mixtures could be estimated semiquantitatively. In addition, we studied their fragmentation mechanisms in N‐acetyl hexosamines such as GlcNAc, which enabled us to quantitatively analyze the structures of the isomers of lactooligosaccharides. The conjugated systems elongate in the chemical species of the Z‐type fragmentation on the 3‐linked GlcNAc owing to the acetoamido groups at the C‐2 positions, which made the chemical species of the Z‐type ions stable. The glycosyl bonds of the front of GlcNAc cleaved easily as a C‐type fragmentation because the negative charge at the anomeric position could be delocalized to the carbonyl oxygen atom at the acetoamido group of GlcNAc. These factors caused the stabilization of the chemical species of the C/Z fragment ions produced by the double cleavage around GlcNAc. Copyright © 2006 John Wiley & Sons, Ltd.
Matrix effects on accurate mass measurements of low‐molecular weight compounds using liquid chromatography‐electrospray‐quadrupole time‐of‐flight mass spectrometry
Authors: Calbiani F. , Careri M. , Elviri L. , Mangia A. , Zagnoni I.
Published: February 2006

Liquid chromatography (LC) with high‐resolution mass spectrometry (HRMS) represents a powerful technique for the identification and/or confirmation of small molecules, i.e. drugs, metabolites or contaminants, in different matrices. However, reliability of analyte identification by HRMS is being challenged by the uncertainty that affects the exact mass measurement. This parameter, characterized by accuracy and precision, is influenced by sample matrix and interferent compounds so that questions about how to develop and validate reliable LC‐HRMS‐based methods are being raised. Experimental approaches for studying the effects of various key factors influencing mass accuracy on low‐molecular weight compounds (MW < 150 Da) when using a quadrupole‐time‐of‐flight (QTOF) mass analyzer were described. Biogenic amines in human plasma were considered for the purpose and the effects of peak shape, ion abundance, resolution and data processing on accurate mass measurements of the analytes were evaluated. In addition, the influence of the matrix on the uncertainty associated with their identification and quantitation is discussed.

A critical evaluation on the calculation of the limits of detection was carried out, considering the uncertainty associated with exact mass measurement of HRMS‐based methods. The minimum concentration level of the analytes that was able to provide a statistical error lower than 5 ppm in terms of precision was 10 times higher than those calculated with S/N = 3, thus suggesting the importance of considering both components of exact mass measurement uncertainty in the evaluation of the limit of detection. Copyright © 2006 John Wiley & Sons, Ltd.
Norman Regional Hospital's magnetic culture attracts employees, pleases customers, and keeps the business healthy
Authors: Shockey Carolyn
Published: February 2006

Normal Regional Hospital envisioned a new culture rooted in the premise that satisfied employees drive patient and physician satisfaction, which leads to business health. The five‐year culture transformation—a broad catalyst for changes in processes, programs, and relationships across the hospital—has benefited all stakeholders and is proving to be a robust model for managing a successful business. © 2006 Wiley Periodicals, Inc.
What's your request?: Wyndham International's answer for transforming culture and enriching employees' experience
Authors: Heis Steve
Published: February 2006

Wyndham Hotels and Resorts was willing to bet that giving guests choices, not points, was the key to building loyalty. When that strategy paid big dividends, the company set out to extend the concept to its workforce by embedding personalization and choice into the work experience and enriching employees'lives in small and large ways. © 2006 Wiley Periodicals, Inc.
Business without boundaries: Collaboration across organizations
Authors: Mankin Don , Cohen Susan G.
Published: February 2006

The authors examine the joint efforts of Deere & Company, several of its dealers, and two technical colleges to develop and sustain programs for training service technicians. The case study offers some key principles for structuring, staffing, and managing complex multiorganizational collaborations to accomplish what a single organization cannot achieve alone. © 2004 John Wiley & Sons, Inc.
In situ SERS study of Rhodamine 6G adsorbed on individually immobilized Ag nanoparticles
Authors: Pristinski Denis , Tan Siliu , Erol Melek , Du Henry , Sukhishvili Svetlana
Published: February 2006

We report a study on polymer‐mediated immobilization of non‐aggregated Ag nanoparticles on planar glass substrates and the resultant surface‐enhanced Raman scattering (SERS) activity using Rhodamine 6G (R6G) as a model molecule. Ag colloidal solution with an average particle diameter of 70 nm was prepared by citrate reduction of AgNO3 using the Lee‐Meisel method, and subsequent fractionation by filtration. A self‐assembled polyallylamine hydrochloride (PAH) monolayer was employed as the intermediate polymer layer. We have shown that the coverage density of Ag nanoparticles on the glass substrates correlates with the amount of adsorbed PAH. This parameter can be easily controlled by varying the pH and ionic strength during polymer deposition. The highest coverage density was obtained for the polymer deposition from buffer solutions at pH 9.0, which additionally contained 0.25 M NaCl. The SERS‐active substrates were robust and stable in 0.5 M NaCl solutions, as well as under extreme acidic and basic conditions. The glass substrates with immobilized non‐aggregated Ag nanoparticles exhibited SERS enhancement and provided in situ detection sensitivity of R6G at 5 ppt level, with estimated surface coverage of two to four R6G molecules per silver particle. We found that adsorption of R6G in the presence of N‐(2‐hydroxyethyl)piperazine‐N′‐(2‐ethanesulfonic acid) (HEPES) buffer resulted in complete inhibition of photodecomposition of adsorbed R6G molecules. Studies of the effect of sodium chloride on the SERS activity of the glass substrates with individually attached nanoparticles showed that chloride anions resulted in a two to threefold increase in SERS intensity. Our approach has enabled the isolation of chloride‐activated SERS enhancement from contributions arising from nanoparticle aggregation. The observed SERS enhancement in salt solutions results from coadsorption of chloride ions by the silver surface, and manifests itself in changing of orientation of adsorbed R6G molecules. The observed enhancement was reversed by exposing the substrate to 514‐nm laser radiation, which resulted in the cleavage of AgCl bonds. Copyright © 2006 John Wiley & Sons, Ltd.
On the rise: India looks for leaders to key its expansion
Authors: Jenkins Joyce
Published: February 2006

Much has changed in India in the past ten years, and it is poised to emerge as a major player in the global economy. But many observers believe that India must further develop its leadership to fulfill its destiny. Here, the CEO of India's largest media conglomerate talks about the changes, choices, and challenges facing leaders in a nation on the brink.
Lyotropic Lamellar Polysiloxanes with Isomeric Amphiphilic Side Chains
Authors: Burgemeister Daniel , Farrell Tony , Schmidt Claudia
Published: February 2006

Summary: This paper presents the synthesis of two polymeric surfactants, consisting of a polysiloxane backbone with amphiphilic side chains of the nonionic oligo(ethylene oxide) type, and their phase behavior in aqueous solution, investigated by polarizing microscopy and deuterium NMR spectroscopy using D2O as a probe. Two different side chains, which are isomeric glycerol derivatives, were synthesized and attached to poly(methyl hydrogen siloxane) by a hydrosilylation reaction, resulting in a tail‐type and a mid‐type polysurfactant. The side chains of the tail‐type system are fixed at the end of the hydrophobic moiety, whereas the side‐chains of the mid‐type system are tethered to the polymer backbone by a short spacer close to the hydrophilic‐hydrophobic junction of the amphiphile. Both polymers form a lamellar phase in aqueous solution over a wide range of concentrations, whereas the side chain precursors do not form lyomesophases. The cloud curve and the lamellar region are observed at lower temperatures in the mid‐type polysurfactant.

Structures of the isomeric polymers forming lamellar phases.

magnified image

Structures of the isomeric polymers forming lamellar phases.
Electronic Structure and Doping Behavior of PANI‐NSA Nanofibers Investigated by Resonance Raman Spectroscopy
Authors: do Nascimento Gustavo M. , Silva Claudio H. B. , Temperini Marcia L. A.
Published: February 2006

Summary: Polyaniline nanofibers (from 93 to 220 nm) doped with β‐naphtalenesulfonic acid (PANI‐NSA) have been characterized. Nonhomogeneity in the thickness of fibers, as can be seen with scanning electron microscopy, is the reason for their instability under the HCl doping process. Resonance Raman spectral profiles of PANI‐NSA fibers suggest a lower protonation state than the emeraldine salt forms. Observation of Raman bands, which are a result of cross‐linking, confirms that one of the properties of the polymeric structure formed in micellar polymerization is the type of connection between chains.

magnified image
Well‐Defined Flexible Polyelectrolytes with Two Cationic Sites per Monomeric Unit
Authors: Mountrichas Grigoris , Mantzaridis Christos , Pispas Stergios
Published: February 2006

Summary: Well‐defined flexible, annealed, and quenched polyelectrolytes with two cationic sites per monomeric unit are synthesized. The synthetic scheme involves the synthesis of narrowly distributed poly(p‐tert‐butoxystyrene) precursors by anionic polymerization high vacuum techniques, hydrolysis to poly(p‐hydroxystyrene), and subsequent quantitative functionalization by a Mannich‐type reaction, to yield annealed polyelectrolytes with two dimethylamino groups per monomer. In a last step, the dimethylamino groups are converted into quaternary ammonium salts by reaction with methyl iodide to give high‐charge‐density quenched cationic polyelectrolytes. The polymers are molecularly characterized by NMR and FT‐IR spectroscopy, while their solution behavior is studied by potentiometric titrations, turbidimetry, and fluorescence spectroscopy as a function of pH, in the case of the annealed polyelectrolytes, as well as by viscometry in the case of the quenched polyelectrolytes.

Schematic diagram of the synthesis of the polyelectrolytes.

magnified image

Schematic diagram of the synthesis of the polyelectrolytes.
Redox‐Responsive Hydrogel System Using the Molecular Recognition of β‐Cyclodextrin
Authors: Tomatsu Itsuro , Hashidzume Akihito , Harada Akira
Published: February 2006

Summary: We have successfully constructed a redox‐responsible hydrogel system by combination of β‐cyclodextrin (β‐CD), dodecyl‐modified poly(acrylic acid) [p(AA/C12)], and a redox‐responsive guest, ferrocenecarboxylic acid (FCA). In the reduced state of FCA, the ternary mixture exhibited a gel‐like behavior, whereas, in its oxidized state, the mixture exhibited a sol behavior.

Conceptual illustration for the redox‐responsive hydrogel system.

magnified image

Conceptual illustration for the redox‐responsive hydrogel system.
Preparation of Arabinoxylan and its Sorption on Bacterial Cellulose During Cultivation
Authors: Winter Heiko , Barakat Abdellatif , Cathala Bernard , Saake Bodo
Published: February 2006

The sorption of arabinoxylan (AX) on bacterial cellulose was investigated by adding AX to the culture medium of Gluconacetobacter xylinus. The starting AX material was produced by alkaline extraction of oat spelts. To investigate the impact of varying AX quality, the residual lignin was reduced by ClO2 bleaching. Furthermore, bleached and unbleached xylans were subjected to xylanase hydrolysis in order to produce fractions of varying molar mass. Of all samples only the water soluble fractions were used for sorption experiments. A reduced molar mass resulted in a lower sorption of AX to the cellulose, while the lignin content increased the sorption of AX on bacterial cellulose. The sorption of AX resulted in a reduction of bacterial cellulose crystallinity and cellulose Iα content. In combined treatments of AX with xyloglucan and β‐glucan no synergistic effect of those polysaccharides on the AX sorption was found.
Role of Hemicelluloses in the Formation of Chromophores During Heat Treatment of Bleached Chemical Pulps
Authors: Beyer Mario , Koch Helmut , Fischer Klaus
Published: February 2006

The heat‐induced colour formation of TCF‐ and ECF‐bleached chemical pulps has been investigated. Partial hydrolysis of the pulps and analysis of the carboxyl content of the pulps and hydrolysed matter were carried out. It was found that the yellowing tendency of the pulps corresponds to the content of hydrolysable substances. The hydrolysis leads to a considerable removal of the carboxyl groups in the case of hardwood pulps. Differences between softwood and hardwood pulps are discussed in terms of their hemicellulose content. The yellowed pulps were extracted and the extracts were analysed by different NMR and mass spectrometric techniques. Structures of low molecular products were elucidated and the routes of their formation were proposed. The results suggest that the yellowing proceeds in two main steps, i.e. decay of unstable polysaccharide chains such as hemicelluloses to low molecular carbohydrate compounds that subsequently undergo dehydration and condensation reactions to form coloured products.
Effect of Glucuronoxylan on the Hornification of Eucalyptus globulus Bleached Pulps
Authors: Rebuzzi Felipe , Evtuguin Dmitry V.
Published: February 2006

The effect of 4‐O‐methylglucuronoxylan (GX) on the hornification of bleached kraft and acid sulphite Eucalyptus globulus chemical pulps has been investigated. Almost straight‐line dependence of kraft pulp hornification from GX content was explained through the diminishing of fibrils aggregation and better accessibility of amorphous cellulose regions to water in GX enriched pulps. The higher hornification of sulphite than kraft pulp was assigned to lower GX content in the former and to unfavourable rearrangement of cellulose molecules in crystalline and amorphous regions during acid sulphite pulping.