bluuebunny/crossref_metadata_2025 huggingface dataset:
A Markov Chain Monte Carlo Method for Estimating Population Mixing Using Y‐chromosome Markers: Mixing of the Han People in China
Authors: Jow H. , Amos W. , Luo H. , Zhang Y. , Burroughs N. J.
Published: December 2006

We present a new approach for estimating mixing between populations based on non‐recombining markers, specifically Y‐chromosome microsatellites. A Markov chain Monte Carlo (MCMC) Bayesian statistical approach is used to calculate the posterior probability distribution of population parameters of interest, including the effective population size and the time to most recent common ancestor (MRCA). To test whether two populations are homogeneously mixed we introduce a “mixing” statistic defined for each coalescent event that weights the contribution of that ancestor's descendants to the two subpopulations, and an associated population “purity” statistic. Using simulated data with low levels of migration between two populations, we demonstrate that our method is more sensitive than other commonly used distance‐based methods such as RST and DSW. To illustrate our method, we analysed mixing between 11 pre‐defined Chinese ethnic/regional populations, using 5 microsatellite markers from the non‐recombining region of the Y‐chromosome (NRY), demonstrating a significant clustering of a subset of subpopulations with a high mutual relative degree of mixing (homogeneous mixing with support >0.99). Our analysis suggests that there is a strong correlation between effective population size and mixing with other subpopulations. Thus, despite considerable mixing between these groups, the purity statistic still identifies significant heterogeneity, suggesting that periods of historical isolation continue to leave a recoverable signal despite modern introgression.
Annotation: Neurofeedback – train your brain to train behaviour
Authors: Heinrich Hartmut , Gevensleben Holger , Strehl Ute
Published: December 2006

Background:  Neurofeedback (NF) is a form of behavioural training aimed at developing skills for self‐regulation of brain activity. Within the past decade, several NF studies have been published that tend to overcome the methodological shortcomings of earlier studies. This annotation describes the methodical basis of NF and reviews the evidence base for its clinical efficacy and effectiveness in neuropsychiatric disorders.

Methods:  In NF training, self‐regulation of specific aspects of electrical brain activity is acquired by means of immediate feedback and positive reinforcement. In frequency training, activity in different EEG frequency bands has to be decreased or increased. Training of slow cortical potentials (SCPs) addresses the regulation of cortical excitability.

Results:  NF studies revealed paradigm‐specific effects on, e.g., attention and memory processes and performance improvements in real‐life conditions, in healthy subjects as well as in patients. In several studies it was shown that children with attention‐deficit hyperactivity disorder (ADHD) improved behavioural and cognitive variables after frequency (e.g., theta/beta) training or SCP training. Neurophysiological effects could also be measured. However, specific and unspecific training effects could not be disentangled in these studies. For drug‐resistant patients with epilepsy, significant and long‐lasting decreases of seizure frequency and intensity through SCP training were documented in a series of studies. For other child psychiatric disorders (e.g., tic disorders, anxiety, and autism) only preliminary investigations are available.

Conclusions:  There is growing evidence for NF as a valuable treatment module in neuropsychiatric disorders. Further, controlled studies are necessary to establish clinical efficacy and effectiveness and to learn more about the mechanisms underlying successful training.
The use of recombinant activated factor VII in obstetric and gynaecological haemorrhage
Authors: Franchini M , Lippi G , Franchi M
Published: December 2006

Recombinant activated factor VII (rFVIIa) was originally developed for the treatment of bleeding in patients with haemophilia A or B and inhibitors. Over the past ten years, it has been successfully used to prevent or control bleeding in several other nonhaemophilic bleeding conditions. Among the newer ‘off‐label’ clinical applications of rFVIIa, there is increasing evidence of its effectiveness in treating obstetric and gynaecological bleeding unresponsive to conventional therapy. The existing literature on the use of rFVIIa in obstetrics and gynaecology is summarised in this review. Although supported by few and uncontrolled studies, on the whole, the published data suggest a potential role of rFVIIa in the management of obstetric and gynaecological intractable bleeding. However, further evidence is needed to improve the assessment of its optimal dose, effectiveness and safety in such conditions.
A prospective Swedish cohort study on psychosocial factors influencing anxiety in women referred for colposcopy*
Authors: Hellsten C , Sjöström K , Lindqvist PG
Published: December 2006

Objectives  To elucidate risk factors for high state anxiety in women referred for colposcopy.

Design  Prospective cohort study.

Setting  Department of Gynaecology, Malmö University Hospital, Sweden.

Population  A total of 100 consecutive women referred for colposcopy for the first time after an abnormal cervical smear.

Methods  Women in the study group completed prior to colposcopy the State–Trait Anxiety Inventory, the Montgomery–Åsberg Depression Rating Scale–self‐rate, and were interviewed about their psychosocial situation.

Main outcome measures  Variables related to high state anxiety were determined in bivariate and multiple logistic regression analysis.

Results  High depression scores and the wording of the referral letter for colposcopy were related to high state anxiety in a multivariate analysis. Women with high depression scores had a nine‐fold risk for higher levels of state anxiety and did not respond with lower state anxiety levels after information and examination. Women who received a letter stating ‘some changes’ were at a five‐fold increased risk for high levels of state anxiety than those who received a letter stating ‘light changes’.

Conclusion  A depressive mood and the wording of the referral letter for colposcopy after an abnormal smear were predictive of high state anxiety levels.
Magnesium sulphate given before very‐preterm birth to protect infant brain: the randomised controlled PREMAG trial*
Authors: Marret S , Marpeau L , Zupan‐Simunek V , Eurin D , Lévêque C , Hellot M‐F , Bénichou J ,   PREMAG trial group
Published: December 2006

Objective  To evaluate whether magnesium sulphate (MgSO4) given to women at risk of very‐preterm birth would be neuroprotective in preterm newborns and would prevent neonatal mortality and severe white‐matter injury (WMI).

Design  A randomised study.

Setting  Eighteen French tertiary hospitals.

Population  Women with fetuses of gestational age < 33 weeks whose birth was planned or expected within 24 hours were enrolled from July 1997 to July 2003 with follow up of infants until hospital discharge.

Methods  Five hundred and seventy‐three mothers were randomly assigned to receive a single 40‐ml infusion of 0.1 g/ml of MgSO4 (4 g) solution or isotonic 0.9% saline (placebo) over 30 minutes. This study is registered as an International Standard Randomised Controlled Trial, number 00120588.

Main outcome measures  The primary endpoints were rates of severe WMI or total mortality before hospital discharge, and their combined outcome. Analyses were based on intention to treat.

Results  After 6 years of enrolment, the trial was stopped. Data from 688 infants were analysed. Comparing infants who received MgSO4 or placebo, respectively, total mortality (9.4 versus 10.4%; OR: 0.79, 95% CI 0.44–1.44), severe WMI (10.0 versus 11.7%; OR: 0.78, 95% CI 0.47–1.31) and their combined outcomes (16.5 versus 17.9%; OR: 0.86, 95% CI 0.55–1.34) were less frequent for the former, but these differences were not statistically significant. No major maternal adverse effects were observed in the MgSO4 group.

Conclusion  Although our results are inconclusive, improvements of neonatal outcome obtained with MgSO4 are of potential clinical significance. More research is needed to assess the protective effect of MgSO4 alone or in combination with other neuroprotective molecules.
The AmRo study: pregnancy outcome in HIV‐1‐infected women under effective highly active antiretroviral therapy and a policy of vaginal delivery
Authors: Boer K , Nellen JF , Patel D , Timmermans S , Tempelman C , Wibaut M , Sluman MA , Van Der Ende ME , Godfried MH
Published: December 2006

Objective  To explore pregnancy outcome in HIV‐1‐positive and HIV‐negative women, and mother‐to‐child transmission (MTCT) according to mode of delivery under effective highly active antiretroviral therapy (HAART).

Design  Cohort of 143 pregnant HIV‐1‐infected women including a matched case–control study in a 2:1 ratio of controls to cases (n = 98).

Setting  Academic Medical Center in Amsterdam and Erasmus Medical Center in Rotterdam, the Netherlands.

Population  Consecutive referred HIV‐1 infected pregnant women treated with HAART and matched control not infected pregnant women.

Main outcome measures  MTCT, preterm delivery, low birthweight, pre‐eclampsia.

Results  MTCT was 0% (95% CI 0–2.1%). Seventy‐eight percent of HIV‐1‐infected women commenced and 62% completed vaginal delivery. The calculated number of caesarean sections needed to prevent a single MTCT was 131 or more. Preterm delivery rates were 18% (95% CI 11–27) in women infected with HIV‐1 and 9% (95% CI 5–13) in controls (P = 0.03). HAART used at <13 weeks of gestation was associated with a 44% preterm delivery rate compared with 21% when HAART was started at or after 13 weeks and 14% in controls. (Very) low birthweight and incidence of pre‐eclampsia were not different between HIV‐1 and controls.

Conclusions  We have not demonstrated any MTCT after vaginal delivery in women effectively treated by HAART. The HAART‐associated increase in preterm delivery rate is mainly seen after first trimester HAART use.
A pilot project of a cancer patient library in Italy: results of a customer‐satisfaction survey and its products
Authors: Truccolo Ivana , Bianchet Katia , Capello Fabia , Russell‐Edu William , Dal Maso Luigino , Colombatti Alfonso , Ciolfi Laura , Tirelli Umberto , De Paoli Paolo
Published: December 2006

Aims: The purpose of this study is to determine the degree of satisfaction of users of the Cancer Information Point section of the Library for Patients (CIP‐LP), active since 1998 at the National Cancer Institute of Aviano, Italy. The CIP‐LP is based on a skilled intermediary, adequate informative material and a specific location, within the Scientific Library of the Institute.

Patients and methods: A survey was developed to assess service functionality and quality from the users’ viewpoint. During a 6‐month period, a questionnaire was mailed to 194 patients and relatives who previously used the CIP‐LP; 113 (58%) were returned and processed.

Results: Of the respondents, 91% were pleased with the CIP‐LP and 95% would recommend the service to other people. The information obtained contributed to a clearer understanding of the illness and treatment (45% as first answer) and a better control of the situation (33%). Fifty‐one per cent evaluated the information received as ‘good’, 42%‘excellent’ and 4%‘of sufficient quality’.

Conclusion: This survey shows the appreciation and usefulness in the users’ perception of a specific hospital library for cancer patients and their relatives, providing an information service supplementary to doctor–patient communication.
The costs and effectiveness of information‐skills training and mediated searching: quantitative results from the EMPIRIC project
Authors: Brettle Alison , Hulme Claire , Ormandy Paula
Published: December 2006

Objectives: To compare the effectiveness and costs of providing information for patient care via librarian‐mediated searches and information‐skills training.

Methods: A questionnaire survey to library staff and health professionals in the North West. Data was collected on perceptions of services, satisfaction and service usage, allowing a cost analysis to be undertaken. Statistical data was analysed using Statistical Package for the Social Sciences (spss).

Results: Using satisfaction and use of skills as outcome measures, both mediated searches and information skills training are effective. A breakdown of costs per type of training session and literature search is provided. Cost‐effectiveness is dependent on whether costs are viewed from a library or trust point of view. Providing information skills training does not reduce the volume of mediated‐search requests.

Conclusions: No one method of providing information for health professionals is more effective or cost‐effective than another. A decision about which services to provide cannot be made on the basis of effectiveness or costs alone; the views of library staff and the health professionals they serve should also be taken into account. A proactive approach and targeting training towards those who are most likely to benefit may be an appropriate way forward.
Two physiotherapists, one librarian and a systematic literature review: collaboration in action
Authors: Swinkels Annette , Briddon Jason , Hall Jane
Published: December 2006

Aim: This paper explores the processes of collaboration between a librarian and two academic physiotherapists working on a systematic review jointly funded by the University of the West of England (UWE), Bristol, and the Royal National Hospital for Rheumatic Diseases (RNHRD), Bath, UK. The aim of this paper is to describe and evaluate some of the processes of collaboration between the three authors in their work in progress on a funded systematic literature review on the topic of hydrotherapy and pain.

Methods: The vehicle for describing and analysing these processes is a joint (National Health Service Trust and University) funded systematic literature review currently in progress on the topic of hydrotherapy and pain.

Results: Systematic review methodology is becoming increasingly complex and is rapidly developing its own research base. Librarian input is a key element in a successful systematic review.

Conclusions: Systematic reviews play a critical role in informing healthcare delivery and research in the UK. The individual nature and inherent complexity of each review demands close collaboration between librarians, academics and clinicians. In addition to enhancing the reviews themselves, there are many other personal and institutional benefits of collaborative working. Consideration may need to be given to library staff structures and roles if these benefits are to be maximized and sustained.
Endogenous N‐acetylaspartylglutamate reduced NMDA receptor‐dependent current neurotransmission in the CA1 area of the hippocampus1
Authors: Bergeron Richard , Imamura Yukio , Frangioni John V. , Greene Robert W. , Coyle Joseph T.
Published: December 2006

N‐Acetylaspartylglutamate (NAAG) is a neuropeptide found in high concentrations in the brain. Using whole‐cell recordings of CA1 pyramidal neurons in acute hippocampal slices, we found that either (i) the application of exogenous NAAG or (ii) an increase of endogenous extracellular NAAG, caused by the inhibition of its catabolic enzyme glutamate carboxypeptidase II (GCP II), resulted in a significant reduction in the amplitude of the isolated NMDA receptor (NMDAR) component of the evoked excitatory postsynaptic current (EPSC). Conversely, reduction of endogenous extracellular NAAG caused by either (i) perfusion with a soluble form of pure human GCP II or (ii) affinity purified antibodies against NAAG, enhanced the amplitude of the isolated NMDAR current. Bath application of GCP II inhibitor induced a progressive loss of spontaneous NMDAR miniatures. Furthermore, NAAG blocked the induction of long‐term potentiation at Schaffer collateral axons–CA1 pyramidal neuron synapses. All together, these results suggest that NAAG acts as an endogenous modulator of NMDARs in the CA1 area of the hippocampus.
Cellular prion protein modulates the intracellular calcium response to hydrogen peroxide
Authors: Krebs Bjarne , Wiebelitz Antje , Balitzki‐Korte Beate , Vassallo Neville , Paluch Sandra , Mitteregger Gerda , Onodera Takashi , Kretzschmar Hans A. , Herms Jochen
Published: December 2006

The physiological function of the cellular prion protein (PrPC) is still under intense investigation. It has been suggested that PrPC has a protective role in neuronal cells, particularly against environmental stress caused by reactive oxygen species (ROS). Here we analysed the acute effect of a major ROS, hydrogen peroxide (H2O2), on intracellular calcium homeostasis in cultured cerebellar granule cells and immortalized hippocampal neuronal cells. Both neuronal cell culture models showed that the rise in intracellular calcium following application of H2O2 was strongly dependent on the presence of PrPC. Moreover, the N‐terminal octapeptide repeats of PrPC were required for this effect, because neuronal cells expressing a PrPC lacking the N‐terminus resembled the PrPC‐deficient phenotype. Neurones deficient of fyn kinase, or pharmacological inhibition of fyn, also abrogated the calcium response to H2O2 treatment, indicating that fyn activation is a critical step within the PrPC signalling cascade. Finally, we identified a possible role of this PrPC signalling pathway in the neuroprotective response of PrPC to oxidative stress. In conclusion, we put forward the hypothesis that PrPC functions as a sensor for H2O2, thereby activating a protective signalling cascade involving fyn kinase that leads to calcium release from intracellular stores.
Selective blockade of dopamine D3versus D2receptors enhances frontocortical cholinergic transmission and social memory in rats: a parallel neurochemical and behavioural analysis
Authors: Millan Mark J. , Di Cara Benjamin , Dekeyne Anne , Panayi Fany , De Groote Lotte , Sicard Dorothée , Cistarelli Laetitia , Billiras Rodolphe , Gobert Alain
Published: December 2006

Though dopaminergic mechanisms modulate cholinergic transmission and cognitive function, the significance of specific receptor subtypes remains uncertain. Here, we examined the roles of dopamine D3versus D2receptors. By analogy with tacrine (0.16–2.5 mg/kg, s.c.), the selective D3receptor antagonists, S33084 (0.01–0.63) and SB277,011 (0.63–40.0), elicited dose‐dependent, pronounced and sustained elevations in dialysis levels of acetylcholine (ACh) in the frontal cortex, but not the hippocampus, of freely‐moving rats. The actions of these antagonists were stereospecifically mimicked by (+)S14297 (1.25), whereas its inactive distomer, (–)S17777, was ineffective. The preferential D2receptor antagonist, L741,626 (10.0), failed to modify levels of ACh. S33084 (0.01–0.63) and SB277,011 (0.16–2.5) also mimicked tacrine (0.04–0.63) by dose‐dependently attenuating the deleterious influence of scopolamine (1.25) upon social memory (recognition by an adult rat of a juvenile conspecific). Further, (+)S14297 (1.25) versus (–)S17777 stereospecifically blocked the action of scopolamine. Using an intersession interval of 120 min (spontaneous loss of recognition), S33084 (0.04–0.63), SB277,011 (0.16–10.0) and (+)S14297 (0.63–10.0) likewise mimicked tacrine (0.16–2.5) in enhancing social memory. In contrast, L741,626 (0.16–10.0) displayed amnesic properties. In conclusion, selective blockade of D3receptors facilitates frontocortical cholinergic transmission and improves social memory in rats. These data support the pertinence of D3receptors as a target for treatment of disorders in which cognitive function is compromised.
FAP: an exclusion‐based parental assignment program with enhanced predictive functions
Authors: TAGGART JOHN B.
Published: December 2006

In molecular‐based parentage analyses, the accurate prediction of resolving power for a panel of loci is important for the critical assessment of results. A DOS‐based computer program, fap (Family Analysis Program), is described that calculates exclusion‐based family assignment probabilities within family mixtures where all parental genotypes are known. Three levels of hierarchy can be explored (sample, groups of families, individual families). The package also provides useful aids to identify problematic loci/misscoring during actual assignment. fap is available for free download from http://www.aqua.stir.ac.uk/rep‐general/downloads.html.
Development of microsatellite markers in the grey‐crowned babbler (Pomatostomus temporalis)
Authors: KAWANO KATSURA M. , EGUCHI KAZUHIRO , UEDA KEISUKE , NOSKE RICHARD
Published: December 2006

The grey‐crowned babbler (Pomatostomus temporalis) is a cooperative breeding bird species in which nonbreeding helpers of both sexes care for the young of breeding individuals. To measure the genetic relatedness between breeders and their offspring and helpers, we developed nine microsatellite markers. Most of the loci were highly polymorphic. These loci will be useful in understanding the evolution and maintenance of cooperative breeding and helping behaviour in this species.
Development of 15 polymorphic genic microsatellite DNA markers of Pacific abalone Haliotis discus hannai
Authors: SUN XIUQING , ZHEN MINGGANG , YANG GUANPIN
Published: December 2006

Fifteen polymorphic genic microsatellite DNA markers were developed based on the expressed sequence tags of Pacific abalone Haliotis discus hannai we ourselves generated, which were used to type 32 individuals representing a cultured population. The number of alleles each locus ranged from two to 12. The observed and expected heterozygosities ranged from 0.094 to 0.969 and from 0.091 to 0.878, respectively. Among 15 loci, four were found to deviate significantly from Hardy–Weinberg equilibrium (PHW < 0.001). No linkage disequilibrium was found between these loci. It is certain that these markers will facilitate the management and exploitation of the genetic resource of Pacific abalone.
Characterization of 18 SNP markers for sperm whale (Physeter macrocephalus)
Authors: MORIN PHILLIP A. , AITKEN NICOLA C. , RUBIO‐CISNEROS NADIA , DIZON ANDREW E. , MESNICK SARAH
Published: December 2006

We report the characterization of 18 new single nucleotide polymorphism (SNP) markers for an endangered species, the sperm whale (Physeter macrocephalus), developed using a targeted gene approach. SNP markers were derived from autosomal regions of the genome using primers originally characterized for genome mapping in other mammals. These SNP markers are the first to be designed for genotyping sperm whale populations and will provide a necessary addition to the genetic tools employed for understanding population structure on a global scale and for developing a conservation management strategy for this endangered species.
No association between socio‐economic status and white blood cell telomere length
Authors: Adams Jean , Martin‐Ruiz Carmen , Pearce Mark S. , White Martin , Parker Louise , Von Zglinicki Thomas
Published: December 2006

It has been hypothesized that more socio‐economically deprived individuals age faster and, thus, have shorter telomeres than their more affluent counterparts. A weak association between white blood cell telomere length and socio‐economic status in a large heterogeneous sample of females has recently been reported. In 318 individuals from a homogeneous birth cohort, we found no evidence of an association between any measure of socio‐economic status and peripheral blood mononucleocyte telomere length at age 50 after control for lifestyle variables, gender and paternal age at birth. The results of this, and the previous study, suggest that there is little evidence of a strong or consistent correlation between white blood cell telomere length and markers of socio‐economic status.
Demographic Issues in Longevity Risk Analysis
Authors: Stallard Eric
Published: December 2006

Abstract

Fundamental to the modeling of longevity risk is the specification of the assumptions used in demographic forecasting models that are designed to project past experience into future years, with or without modifications based on expert opinion about influential factors not represented in the historical data. Stochastic forecasts are required to explicitly quantify the uncertainty of forecasted cohort survival functions, including uncertainty due to process variance, parameter errors, and model misspecification errors. Current applications typically ignore the latter two sources although the potential impact of model misspecification errors is substantial. Such errors arise from a lack of understanding of the nature and causes of historical changes in longevity and the implications of these factors for the future. This article reviews the literature on the nature and causes of historical changes in longevity and recent efforts at deterministic and stochastic forecasting based on these data. The review reveals that plausible alternative sets of forecasting assumptions have been derived from the same sets of historical data, implying that further methodological development will be needed to integrate the various assumptions into a single coherent forecasting model. Illustrative calculations based on existing forecasts indicate that the ranges of uncertainty for older cohorts' survival functions will be at a manageable level. Uncertainty ranges for younger cohorts will be larger and the need for greater precision will likely motivate further model development.
Personalism, Particularism, and the Competitive Behaviors and Advantages of Family Firms: An Introduction
Authors: Chrisman James J. , Steier Lloyd P. , Chua Jess H.
Published: December 2006

Fundamental assumptions of any theory of the family firm are that family firms will behave in ways that differ from nonfamily firms, and that the behaviors of family firms will also exhibit substantial variations. This special issue includes a set of articles and commentaries that study such differences. This introduction synthesizes these articles using the concepts of personalism and particularism. We argue that the set of articles contained in this special issue contributes to the literature by explaining how the ability and willingness of family firms to behave in an idiosyncratic fashion leads to advantages and disadvantages that distinguish between family and nonfamily firms and between different types of family firms.
Family Firms and Social Responsibility: Preliminary Evidence from the S&P 500
Authors: Dyer W. Gibb , Whetten David A.
Published: December 2006

Little is known about the impact of family ownership and management on corporate social performance. Some scholars have suggested that family firms are not likely to act in a socially responsible manner, while others have indicated that socially responsible behavior on the part of the family firm protects the family's assets. This preliminary study compares the degree to which family and nonfamily firms are socially responsible using data from 1991 to 2000 from the S&P 500. Two hundred sixty–one firms (202 nonfamily and 59 family) appeared in the S&P 500 for the 10–year period. Findings show that family firms are more socially responsible than nonfamily firms along several dimensions. This is likely due to family concern about image and reputation and a desire to protect family assets.
If Theories of Family Enterprise Really Do Matter, So Does Change in Management Education
Authors: Steier Lloyd P. , Ward John L.
Published: December 2006

This article focuses on family business as an emerging field within management studies. Drawing on a purposive sample of 10 articles presented at a recent academic conference as illustrative of current research in family business, we contend that one of the most salient implications for practice is management education. Subscribing to a logic that good scholarship should inform what is taught in business schools, the article further establishes family business as a field of study by developing a research–based heuristic useful for ongoing curriculum inquiry and development.
Deformation and Cracking in Ge–Sb–Se Chalcogenide Glasses During Indentation
Authors: Varshneya Arun K. , Mauro Daniel J. , Rangarajan Badri , Bowden Bradley F.
Published: December 2006

Deformation and cracking behavior of Ge–Sb–Se binary and ternary chalcogenide glasses of varying average covalent coordination number, 〈r〉, was studied by indenting with Vickers and Brinell microindenters using static and recording machines, and subsequent analysis using a non‐contact profilometer. Vickers‐produced cracks were the smallest around the GeSe4 composition (〈r〉=2.4) after unloading, hence the indentation toughness was a maximum and the brittleness a minimum at 〈r〉=2.4. Brinell‐created pond (crater) depth, the mound (pile‐up) height, and the radial fractures originating from the mounds displayed minima in the binaries, presumably due to maximized elastic recovery around 〈r〉=2.4. Consequently, Brinell hardness computed from the unloaded depth (HBD) showed a maximum around GeSe4. The maximized elastic recovery around GeSe4 is consistent with Phillips' optimized connectivity arguments. GeSe4 resembles the “anomalous” SiO2 glass for deformation and cracking behavior. Surprisingly, many of the extrema were nearly non‐existent in the ternary glasses. The apparent contrast to the binary glasses is not understood.
Kinetic Model for TiO2 Polymorphic Transformation from Anatase to Rutile
Authors: Madras Giridhar , McCoy Benjamin J. , Navrotsky Alexandra
Published: December 2006

We propose a distribution kinetics model for the polymorphic transformation (anatase to rutile) and coarsening of TiO2. Based on population balance equations for the size distributions of the dimorphs, the simplified model applies a first‐order rate expression for transformation combined with Smoluchowski coalescence for coarsening of anatase and rutile particles. Two moments of the size distributions (number and mass of particles) lead to dynamic expressions for extent of reaction and average particle diameter. The model describes the time‐dependent data of Banfield and colleagues fairly accurately, and provides activation energies for anatase coalescence and transformation. The equilibrium constant for the microscopically reversible transformation, occurring without coarsening, yields a small endothermic enthalpy change per mole of TiO2. This probably reflects contributions of the transformation enthalpy of the anhydrous phases at the given particle size, which is very close to 0, and the enthalpy associated with a small amount of dehydration (endothermic water evaporation) during transformation.
Fully vs. partially rough implants in maxillary sinus floor augmentation: a randomized‐controlled clinical trial
Authors: Stavropoulos Andreas , Karring Thorkild , Kostopoulos Lambros
Published: December 2006

Objectives: To compare implants with a rough surface in their whole length (FR) with implants having a 2 mm coronal machined portion (PR) when used in association with a sinus‐lift procedure.

Material and methods: Twenty‐six patients with 2 mm≤x≤9 mm residual alveolar crest were prosthetically restored with implants after a staged sinus‐lift procedure using osteotomes. In 13 randomly chosen patients, no more than one FR implant was placed (test group), while the rest were PR implants. The other 13 patients received only PR implants (control group). For comparisons, only one implant from each patient was used, i.e., from the test group only the 13 FR implants were used, while from the control group, one PR implant was randomly chosen. The presence/absence of plaque, BOP, PPD and REC were registered at the day of delivery of the restorations and after 1 year. Residual alveolar crest height and marginal bone levels around the implants were evaluated on standardized periapical radiographs taken at various stages.

Results: Four FR and two PR implants were lost, and the cumulative survival rate was 82.9% (six lost out of 35). There were no significant differences between the two groups. Implant type, residual alveolar crest height, time of osseointegration, time of implant loading and smoking did not seem to influence implant survival.

Conclusions: FR and PR implants placed in augmented sinuses did not differ in their clinical performance.
Therapy with hydroxyurea is associated with reduced adhesion molecule gene and protein expression in sickle red cells with a concomitant reduction in adhesive properties
Authors: Gambero Sheley , Canalli Andreia A. , Traina Fabiola , Albuquerque Dulcinéia M. , Saad Sara T.O. , Costa Fernando F. , Conran Nicola
Published: December 2006

Propagation of the vaso‐occlusive process in sickle cell anaemia (SCA) is a complex process involving the adhesion of steady–state SCA patients red cells and reticulocytes to the vascular endothelium. The effect of hydroxyurea therapy (HUT) on the adhesive properties of sickle cells and the expression of adhesion molecule genes by erythroid cells of SCA individuals is not yet fully understood. The expressions of the CD36 gene and the VLA‐4‐integrin subunit genes, CD49d (α‐subunit) and CD29 (β‐subunit), were compared in the reticulocytes of steady–state SCA patients and patients on HUT using real‐time PCR. Basal adhesion of red cells from these subjects was also compared using static adhesion assays, as was surface protein expression, using flow cytometry. Basal sickle red cell adhesion to fibronectin was significantly greater than that of normal cells (P < 0.01); in contrast, HUT was associated with significantly lower levels (P < 0.01) of red cell adhesion that were similar to those of control cells; this decrease could not be justified solely by altered reticulocyte numbers in this population. Accordingly, flow cytometry demonstrated that reticulocytes from patients on HUT had significantly lower CD36 and CD49d surface expressions (P < 0.01) and, importantly, significantly lower expressions of the CD36, CD49d and CD29 genes (P < 0.05) than reticulocytes of SCA patients not on HUT. Taken together, data support the hypothesis that HUT reduces the adhesive properties of sickle cells and that this decrease appears to be mediated, at least in part, by a decrease in the gene and, consequently, surface protein expression of adhesion molecules such as VLA‐4 and CD36.
Identification of intracellular oral species within human crevicular epithelial cells from subjects with chronic periodontitis by fluorescence in situ hybridization
Authors: Colombo A. V. , Da Silva C. M. , Haffajee A. , Colombo A. P. V.
Published: December 2006

Background and Objective:  Interactions between oral bacteria and gingival epithelial cells play an important role in the pathogenesis of periodontal diseases. This study used in situ hybridization with 16 rRNA probes and confocal microscopy to detect the periodontal pathogens Porphyromonas gingivalis, Actinobacillus actinomycetemcomitans, Tannerella forsythia, and Treponema denticola within epithelial cells from periodontal pockets, gingival crevice, and buccal mucosa collected from subjects with chronic periodontitis (n = 14) and good periodontal health (n = 8).

Material and Methods:  Each green fluorescent species‐specific and universal probe was hybridized with all 58 epithelial samples from the 22 patients. The samples were observed by confocal microscopy to confirm the intracellular localization of oral species of bacteria. The mean frequency of detection and number of intracellular bacteria per epithelial cell were computed for each sample.

Results:  The frequency of cells with internalized bacteria was higher in samples from the gingival crevice than in samples from the oral mucosa. Epithelial cells from all subjects harbored intracellular bacteria; however, patients with periodontitis presented significantly higher counts of bacteria per cell than periodontally healthy individuals (p < 0.05). Periodontal pathogens showed a trend to be detected in higher numbers in epithelial cells from periodontitis patients. In particular, T. forsythia and T. denticola were significantly more prevalent in periodontal pocket cells than healthy sulci and buccal cell samples in the periodontitis group (p < 0.05).

Conclusion:  Those findings indicate that crevicular and buccal cells present internalized bacteria, regardless of periodontal status. However, higher bacterial loads are detected in cells from subjects with periodontitis.
The impact of treatment of dental trauma on the quality of life of adolescents – a case‐control study in southern Brazil
Authors: Ramos‐Jorge Maria Letícia , Bosco Vera Lúcia , Peres Marco Aurélio , Nunes Ana Cristina Gerent Petry
Published: December 2006

Abstract –  The aim of this study was to investigate the impact of treatment for Enamel‐Dentin Fracture (EDF) on the daily activities of adolescents. This was a case‐control study (1:4). The case group was composed of 40 adolescents from 11 to 17 years of age, presenting definitive restoration treatment for EDF for over 6 months. The control group was made up of 160 adolescents with no history of dental trauma and belonging to the circle of friends of the participants of the case group, matched by gender, age, and socioeconomic level. The outcome variable ‘impact’ was assessed through the Oral Impact on Daily Performances (OIDP). The independent variables were collected for being of interest to the study (dental trauma) or for acting as potential confounding factors (malocclusion, decay, and mother's education). Descriptive, univariate, simple and multiple logistic regression analyses were performed. Among the cases, the impact prevalence was 40.0%, whereas among the controls it was 16.9%. The more affected daily activities were showing the teeth (18.0%), eating (6.5%), speaking (2.0%), and cleaning the mouth (0.5%). The odds ratio of adolescents treated for EDF of presenting an impact on daily activities was 3.3 times (confidence interval 95%: 1.4–7.7) greater than among adolescents without dental trauma, controlling for mother's education, decay and the presence of malocclusion. Adolescents whose teeth have been esthetically treated for EDFs run a greater risk of presenting OIDP when compared to adolescents that have never suffered dental injuries.
Traumatic dental injuries and associated factors among Brazilian preschool children
Authors: Oliveira Luciana Butini , Marcenes Wagner , Ardenghi Thiago Machado , Sheiham Aubrey , Bönecker Marcelo
Published: December 2006

Abstract –  The main objective of this study was to assess the epidemiology of traumatic dental injuries (TDI) to the primary teeth of preschool children and second, to investigate whether TDI were related to anterior open bite and, third, whether TDI are related to socio‐economic circumstances in an urban Brazilian population. A clinical examination was performed during the National Day of Children's Vaccination. TDI were classified according to the modified classification proposed by Ellis. In addition to those criteria the presence of tooth discoloration was recorded. An interview was carried out with mothers or guardians. The data collected included mother's level of education and living conditions. The prevalence of TDI was 9.4%. The maxillary central incisors were the most affected teeth. Most children with a TDI experienced traumatic injuries to one tooth (6.3%), while 2.8% had two and 0.4% had three traumatized teeth. The most common crown fracture was in enamel only (68.8%), followed by crown fracture of enamel and dentin (13.8%). Missing teeth following trauma occurred in 10.9% of those with TDI. The prevalence of tooth discoloration was 5.1%. Children with anterior open bite had twice the level the level of TDI compared to those with normal occlusions (P = 0.001). Socio‐economic factors were not statistically significantly associated with the occurrence of TDI. The prevalence of dental injuries in Brazilian preschool children was low. Children with anterior open bite experienced more dental injuries. Neither of the indicators of socio‐economic status was related to the prevalence of TDI.
Impact of Elevated PCO2 on Mass Flow of Reduced Nitrogen in Trees†
Authors: Liu Xi‐Ping
Published: December 2006

To analyze the effects of elevated carbon dioxide concentration (PCO2) on the mass flow of reduced nitrogen (N) in the phloem and xylem of trees, juvenile beech (Fagus sylvatica L.) and spruce (Picea abies (L.) Karst.) were grown in phytotrons and exposed to ambient and elevated PCO2 (plus 687.5 mg/m3 CO2) for three growing seasons. Elevated PCO2 significantly decreased the mass flow of N from the shoot to roots of beech by significantly reducing the concentration of soluble amino compounds in the phloem, even if the area of conductive phloem of cross‐sectional bark tissue was significantly increased, because of less callus deposition in the sieve elements. In spruce, the downward mass flow of reduced N also tended to be decreased, similar to that in beech. Resembling findings in the phloem, N mass flow from roots to shoot in both tree species was significantly diminished owing to significantly reduced concentrations of amino compounds in the xylem and a lower transpiration rate. Therefore, the mass flow of reduced N between shoots and roots of trees was mainly governed by the concentrations of soluble amino compounds in the phloem and xylem in relation to the loading of reduced N in both long‐distance transport pathways.

(Managing editor: Ya‐Qin Han)
Functional Characterization of Mi, a Root‐knot Nematode Resistance Gene from Tomato (Lycopersicon esculentum L.)
Authors: Chen Ru‐Gang , Zhang Li‐Ying , Zhang Jun‐Hong , Zhang Wei , Wang Xue , Ouyang Bo , Li Han‐Xia , Ye Zhi‐Biao
Published: December 2006

Root‐knot nematodes (Meloidogyne spp.) cause major economic damage to numerous crop species around the world. Plant resistance is the most important attribute that is able to suppress invasion by the root‐knot nematodes. In the present study, a candidate root‐knot nematode resistance gene (Mi) was isolated from the resistant tomato (Lycopersicon esculentum L.) line RN‐1. Expression profiling analysis revealed that this gene was expressed specifically in the roots, stems, and leaves, but not in the flowers or fruits. To verify the real function of this candidate gene, both sense and inteference RNA (RNAi) vectors were constructed. We obtained 31 transgenic plants with between one and seven copies of T‐DNA inserts of sense Mi from two nematode‐susceptible tomato cultivars as assayed by polymerase chain reaction (PCR) and Southern blotting analysis. Reverse transcription‐PCR analysis revealed that expression levels of the Mi gene varied in different transgenic plants. Nematode assays showed that the resistance to root‐knot nematodes was significantly improved in some transgenic lines compared with untransformed susceptible controls and that the resistance was heritable in selfed progeny. Loss of function via RNAi further confirmed the role of the Mi gene and the original resistant lines became susceptible to root‐knot nematodes.

(Managing editor: Li‐Hui Zhao)
Rice Mitochondrial Genes Are Transcribed by Multiple Promoters That Are Highly Diverged
Authors: Zhang Qun‐Yu , Liu Yao‐Guang
Published: December 2006

Plant mitochondrial genes are often transcribed into complex sets of mRNA. To characterize the transcription initiation and promoter structure, the transcript termini of four mitochondrial genes, atp1, atp6, cob, rps7, in rice (Oryza sativa L.), were determined by using a modified circularized RNA reverse transcription‐polymerase chain reaction method. The results revealed that three genes (atp1, atp6, rps7) were transcribed from multiple initiation sites, indicating the presence of multiple promoters. Two transcription termination sites were detected in three genes (atp6, cob, rps7), respectively. Analysis on the promoter architecture showed that the YRTA (Y=T or C, R=A or G) motifs that are widely present in the mitochondrial promoters of other monocotand dicot plant species were detected only in two of the 12 analyzed promoters. Our data suggest that the promoter sequences in the rice mitochondrial genome are highly diverged in comparison to those in other plants, and the YRTA motif is not an essential element for the promoter activity.

(Managing editor: Li‐Hui Zhao)
Photosynthetic Properties of Photosystem II in Arabidopsis thaliana Ipa1 Mutant
Authors: Peng Lian‐Wei , Guo Jin‐Kui , Ma Jin‐Fang , Chi Wei , Zhang Li‐Xin
Published: December 2006

In a previous study, we characterized a high chlorophyll fluorescence Ipa1 mutant of Arabidopsis thaliana, in which approximately 20% photosystem (PS) II protein is accumulated. In the present study, analysis of fluorescence decay kinetics and thermoluminescence profiles demonstrated that the electron transfer reaction on either the donor or acceptor side of PSII remained largely unaffected in the Ipa1 mutant. In the mutant, maximal photochemical efficiency (Fv/Fm, where Fm is the maximum fluorescence yield and Fv is variable fluorescence) decreased with increasing light intensity and remained almost unchanged in wild‐type plants under different light conditions. The Fv/Fm values also increased when mutant plants were transferred from standard growth light to low light conditions. Analysis of PSII protein accumulation further confirmed that the amount of PSII reaction center protein is correlated with changes in Fv/Fm in Ipa1 plants. Thus, the assembled PSII in the mutant was functional and also showed increased photosensitivity compared with wild‐type plants.

(Managing editor: Ping He)
Antioxidant Mechanism of Milk Mineral—High‐Affinity Iron Binding
Authors: Allen K. , Cornforth D.
Published: December 2006

ABSTRACT:  Milk mineral (MM), a by‐product of whey processing, is an effective antioxidant in meat systems, but the antioxidant mechanism has not been established. MM has been postulated to chelate iron and prevent iron‐catalysis of lipid oxidation. The objective of this research was to examine this putative mechanism. MM was compared to sodium tripolyphosphate (STPP), calcium phosphate monobasic (CPM), and calcium pyrophosphate (CPP) to determine iron‐binding capacity, sample solubility, and eluate soluble phosphorus after treating samples with a ferrous chloride standard. Scanning electron microscopy with energy‐dispersive X‐ray analysis was used to localize minerals on iron‐treated MM particle surfaces. Histochemical staining for calcium was performed on raw and cooked ground beef samples with added MM. MM bound more iron per gram (P < 0.05) than the other compounds, and was much less soluble (P < 0.05) than either STPP or CPM. Mineral localization showed an even distribution of calcium, phosphorus, oxygen, and iron across the MM particle surface, directly demonstrating iron binding to MM particles. Unlike other common chelating agents, such as STPP and citrate, histochemical staining demonstrated that MM remained insoluble in ground beef, even after cooking. The ability of MM to bind iron and remain insoluble may enhance its antioxidant effect by removing iron ions from solution. However, MM particles must be small and well distributed in order to adequately bind iron throughout the food system.