bluuebunny/crossref_metadata_2025 huggingface dataset:
Impact of local and systemic factors on the incidence of failures up to abutment connection with modified surface oral implants
Authors: Alsaadi Ghada , Quirynen Marc , Michiles Katleen , Teughels Wim , Komárek Arnošt , Van Steenberghe Daniel
Published: November 2007

Aim: This study aimed to assess the influence of systemic and local bone and intra‐oral factors on the occurrence of early TiUnite™ implant failures.

Material and Methods: A total of 283 consecutive patients (187 females; mean age 56.2), who received a total of 720 TiUnite™ implants, at the Department of Periodontology of the University Hospital of the Catholic University of Leuven, were prospectively followed.

The following aspects were particularly assessed: hypertension, cardiac problems, gastric problems, osteoporosis, hypo‐ or hyperthyroid, hypercholesterolaemia, asthma, diabetes types I or II, Crohn's disease, rheumatoid arthritis, chemotherapy, hysterectomy and intake of medication (antidepressants, steroids, hormone replacement), radiotherapy of the concerned area, breach of sterility during surgery, implant parameters, bone (quality, quantity, dehiscence or perforation), type of edentulism, antibiotics prescription, fenestration of the implant in the sinus/nasal cavity, immediate implant placement, apical lesion detection and insertion torque.

Results and Conclusion: A global failure rate of 1.9% was recorded. Owing to the very few failures, no definitive conclusion concerning statistical significance can be achieved. However, a tendency for more failures was noticed for apical lesions, vicinity with natural dentition, smoking, hormone replacement, gastric problems, Crohn's disease, diabetes I and radical hysterectomy.
When choice in retirement decisions is missing: Qualitative and quantitative findings of impact on well‐being
Authors: Quine Susan , Wells Yvonne , De Vaus David , Kendig Hal
Published: November 2007

Objectives:  To explore the importance of choice in retirement decisions for subsequent well‐being.

Methods:  A sequential ‘mixed methods’ strategy using qualitative (focus groups) and quantitative (prospective panel survey) methods was adopted. Eleven focus groups were conducted and transcripts were analysed for themes. The panel study (n = 601) comprised mature‐age employees who retired or were made redundant in 1998–1999 and were followed up for three years post‐retirement.

Results:  The findings of the qualitative and quantitative studies were congruent. The qualitative study identified a sense of choice as central to understanding how people adjust to the retirement transition, and the quantitative study confirmed that choice was a strong, consistent predictor of several health and well‐being outcomes and identified predictors of having a sense of choice in retirement.

Conclusion:  Enabling retirees to retain a sense of choice and control is very important to well‐being immediately after retirement and up to three years later.
Genome‐wide Expression Profiling in Seedlings of the Arabidopsis Mutant uro that is Defective in the Secondary Cell Wall Formation
Authors: Yuan Zheng , Yao Xuan , Zhang Dabing , Sun Yue , Huang Hai
Published: November 2007

Plant secondary growth is of tremendous importance, not only for plant growth and development but also for economic usefulness. Secondary tissues such as xylem and phloem are the conducting tissues in plant vascular systems, essentially for water and nutrient transport, respectively. On the other hand, products of plant secondary growth are important raw materials and renewable sources of energy. Although advances have been recently made towards describing molecular mechanisms that regulate secondary growth, the genetic control for this process is not yet fully understood. Secondary cell wall formation in plants shares some common mechanisms with other plant secondary growth processes. Thus, studies on the secondary cell wall formation using Arabidopsis may help to understand the regulatory mechanisms for plant secondary growth. We previously reported phenotypic characterizations of an Arabidopsis semi‐dominant mutant, upright rosette (uro), which is defective in secondary cell wall growth and has an unusually soft stem. Here, we show that lignification in the secondary cell wall in uro is aberrant by analyzing hypocotyl and stem. We also show genome‐wide expression profiles of uro seedlings, using the Affymetrix GeneChip that contains approximately 24 000 Arabidopsis genes. Genes identified with altered expression levels include those that function in plant hormone biosynthesis and signaling, cell division and plant secondary tissue growth. These results provide useful information for further characterizations of the regulatory network in plant secondary cell wall formation.
Elevated Activity and Microglial Expression of Myeloperoxidase in Demyelinated Cerebral Cortex in Multiple Sclerosis
Authors: Gray Elizabeth , Thomas Taya L. , Betmouni Samar , Scolding Neil , Love Seth
Published: November 2007

Recent studies have revealed extensive cortical demyelination in patients with progressive multiple sclerosis (MS). Demyelination in gray matter lesions is associated with activation of microglia. Macrophages and microglia are known to express myeloperoxidase (MPO) and generate reactive oxygen species during myelin phagocytosis in the white matter. In the present study we examined the extent of microglial activation in the cerebral cortex and the relationship of microglial activation and MPO activity to cortical demyelination. Twenty‐one cases of neuropathologically confirmed multiple sclerosis, with 34 cortical lesions, were used to assess microglial activation. HLA‐DR immunolabeling of activated microglia was significantly higher in demyelinated MS cortex than control cortex and, within the MS cohort, was significantly greater within cortical lesions than in matched non‐demyelinated areas of cortex. In homogenates of MS cortex, cortical demyelination was associated with significantly elevated MPO activity. Immunohistochemistry revealed MPO in CD68‐positive microglia within cortical plaques, particularly toward the edge of the plaques, but not in microglia in adjacent non‐demyelinated cortex. Cortical demyelination in MS is associated with increased activity of MPO, which is expressed by a CD68‐positive subset of activated microglia, suggesting that microglial production of reactive oxygen species is likely to be involved in cortical demyelination.
Action of Disinfectants on Canine Coronavirus Replication In Vitro
Authors: Pratelli A.
Published: November 2007

Canine coronavirus (CCoV) is responsible for enteric disease in pups. Infected dogs generally have a rapid recovery, so the virus is highly contagious and the spread of infection is difficult to control. Chemical disinfectants have been widely used in human disease‐control programmes to prevent viral infectious diseases from spreading, but to date, there are no studies in the literature on the sensitivity of CCoV to chemical biocides. The present study investigated the sensitivity of CCoV to disinfectants currently used for prophylaxis in kennel and dog breeding locations. The effects of three agents: alkyl‐dimethyl‐benzyl‐ammonium chloride, benzalkonium chloride and didecyl‐dimethyl‐ammonium chloride, on the infectivity titre of CCoV in A72 cell lines, were studied at different concentrations. Although they may regard a small number of agents, the findings showed that the sensitivity of CCoV to disinfectants varies and the differences are dose correlated. In general, virus inactivation implies a permanent loss of infectivity which can be evaluated in suspensions and hand disinfection tests.
Significant effect of hepatitis C virus specific CTLs on viral clearance in patients with type C chronic hepatitis treated with antiviral agents
Authors: Satake Shinichi , Nagaki Masahito , Kimura Kiminori , Naiki Takafumi , Hayashi Hideki , Sugihara Junichi , Tomita Eiichi , Moriwaki Hisataka
Published: November 2007

Aim:  To evaluate the correlation between hepatitis C virus (HCV) specific cytotoxic T lymphocytes (CTLs) and viral clearance in antiviral treated patients, we examined the number and function of HCV epitope‐specific CTLs and the viral load in 12 HLA‐A2‐positive patients with chronic hepatitis C, after undergoing interferon therapy.

Methods:  Peripheral blood mononuclear cells (PBMC) were analyzed on days 0, 3, 7, 14 and 28 of undergoing antiviral therapies. To investigate the quantity of the antigen specific CTLs, CD8‐positive T cells were isolated using microbeads and were stained for HLA‐A*0201 tetramers. To investigate the function of CTLs, PBMC were stimulated with the same synthetic epitope peptides and analyzed to determine their interferon (IFN)‐γ expression.

Results:  In seven patients, HCV‐RNA became undetectable 4 weeks after antiviral therapies (EVR), but five patients were non‐responders (NR). In peptide NS3 1406 on day 3 and day 7 of therapy and in NS3 1073 on day 3 of therapy, the level of IFN‐γ expression on CD8+ T cells was significantly higher in the EVR group than in the NR group. In other peptides, the number of and cytokine production from the CTLs in the EVR group were also higher than in the NR group, but not significantly.

Conclusion:  After antiviral therapy, analysis of the number and function of antigen‐specific CTLs in the early phase was thus found to be useful for predicting viral clearance in chronic hepatitis C patients.
Partial splenic embolization
Authors: Yoshida Hiroshi , Mamada Yasuhiro , Taniai Nobuhiko , Tajiri Takashi
Published: November 2007

Partial splenic embolization (PSE) is a non‐surgical procedure developed to treat hypersplenism as a result of hepatic disease and thus avoid the disadvantages of splenectomy. A femoral artery approach is used for selective catheterization of the splenic artery. Generally, the catheter tip is placed as distally as possible in an intrasplenic artery. After an injection of antibiotics and steroids, embolization is achieved by injecting 2‐mm gelatin sponge cubes suspended in a saline solution containing antibiotics. PSE can benefit patients with thrombocytopenia, esophagogastric varices, portal hypertensive gastropathy, encephalopathy, liver dysfunction, splenic aneurysm, and splenic trauma. The contraindications of PSE include secondary splenomegaly and hypersplenism in patients with terminal‐stage underlying disease; pyrexia or severe infections are associated with a high risk of splenic abscess after PSE. Complications of PSE include daily intermittent fever, abdominal pain, nausea and vomiting, abdominal fullness, appetite loss, and postembolization syndrome. Decreased portal‐vein flow and a rapid increase in the platelet count after excessive embolization may cause portal‐vein or splenic‐vein thrombosis.
Roles of nuclear factor‐κB in postischemic liver
Authors: Shin Thomas , Kuboki Satoshi , Lentsch Alex B.
Published: November 2007

Hepatic ischemia/reperfusion (I/R) results in a chain of events that culminate in liver dysfunction and injury. I/R injury is characterized by early oxidant stress followed by an intense acute inflammatory response that involves the transcription factor nuclear factor (NF)‐κB. In addition to being a primary regulator of pro‐inflammatory gene expression, NF‐κB may play other roles in the hepatic response to I/R, such as mediating the expression of anti‐apoptotic genes, preventing the accumulation of damaging reactive oxygen species, facilitating liver regeneration, and mediating the protective effects of ischemic preconditioning. In the present study, we review the diverse functions of NF‐κB during hepatic I/R injury.
Low beta diversity of ambrosia beetles (Coleoptera: Curculionidae: Scolytinae and Platypodinae) in lowland rainforests of Papua New Guinea
Authors: Hulcr Jiri , Novotny Vojtech , A. Maurer Brian , I. Cognato Anthony
Published: November 2007

We assessed the effect of geographical distance on insect species turnover in a situation where other major environmental factors, including host plant species, altitude, and climate, were constant. We sampled ambrosia beetles (Coleoptera, Curculionidae: Scolytinae and Platypodinae) from four tree species: Artocarpus altilis, Ficus nodosa, Leea indica and Nauclea orientalis, at three sites forming a 1000 km transect in lowland rainforests of northern Papua New Guinea. A standardized volume of wood from trunk, branches and twigs was sampled for ambrosia beetles from three individuals of the four tree species at each site. Each tree was killed standing and left exposed to beetle colonization for 20 days prior to sampling. We obtained 12 751 individuals from 84 morphospecies of ambrosia beetles. We surveyed most of the local species richness at each site, predicted by Chao 2 species richness estimates. The similarity of ambrosia beetle communities, estimated by Chao‐Sorensen index, was not correlated with their geographical distance. Likelihood analysis and Q‐mode analysis using Monte Carlo‐generated null distribution of beetles among sites supported the hypothesis that the assemblages of ambrosia beetles at different sites are drawn from the same species pool, regardless of their geographical distance. Tree part (trunk, branch, or twig) was more important predictor of the composition of ambrosia beetle communities than was the host species or geographical location. All three variables, however, explained only a small portion of variability in ambrosia assemblages. The distribution of ambrosia beetles among tree parts, tree species and study sites was mostly random, suggesting limited importance of host specificity or dispersal limitation.
Evidence from proprioception of fusimotor coactivation during voluntary contractions in humans
Authors: Allen Trevor J. , Ansems Gabrielle E. , Proske Uwe
Published: November 2007

In experiments on position sense at the elbow joint in the horizontal plane, blindfolded subjects were required to match the position of one forearm (reference) by placement of their other arm (indicator). Position errors were measured after conditioning elbow muscles of the reference arm with an isometric contraction while the arm was held either flexed or extended. The difference in errors after the two forms of conditioning was large when the conditioned muscles remained relaxed during the matching process and it became less when elbow muscles were required to lift a load during the match (10 and 25% of maximal voluntary contraction, respectively). Errors from muscle conditioning were attributed to signals arising in muscle spindles and were hypothesized to result from the thixotropic property of passive intrafusal fibres. Active muscle does not exhibit thixotropy. It is proposed that during a voluntary contraction the errors after conditioning are less, because the spindles become coactivated through the fusimotor system. The distribution of errors is therefore seen to be a reflection of fusimotor recruitment thresholds. For elbow flexors most, but not all, fusimotor fibres appear to be recruited by 10% of a maximal contraction.
Novel Chimeric Genotype 1b/2a Hepatitis C Virus Suitable for High-Throughput Screening
Authors: Zhang Yingjia , Weady Peter , Duggal Rohit , Hao Weidong
Published: November 2007

A major obstacle in hepatitis C virus (HCV) research has been the lack of a permissive cell culture system that produces infectious viral particles. Significant breakthroughs have been achieved lately in establishing such culture systems. Yet to date, there are no reports of the applications of any of these systems in HCV drug screening. Here, we report the generation of two monocistronic, chimeric genotype 1 full-length HCV genome molecules. These molecules, C33J-Y835C-UBI and C33J-Y835C-FMDV2A, both contain the structural protein region from genotype 1 (subtype 1b, Con1) and the remaining region from the genotype 2a (JFH1) clone. Both contain the humanized
Renilla
luciferase reporter gene which is separated from the rest of the HCV open reading frame by two different cleavage sites. The viral RNAs replicated efficiently in transfected cells. Viral particles produced were infectious in naïve Huh7.5 cells, and the infectivity could be blocked by monoclonal antibody against a putative HCV entry cofactor, CD81. A pilot high-throughput screen of 900 unknown compounds was executed by both the genotype 2a subgenomic replicon system and the infectious system. Thirty-one compounds were identified as hits by both systems, whereas 78 compounds were identified as hits only for the infectious system, suggesting that the infectious system is capable of identifying inhibitors targeting the viral structural proteins and steps involving them in the viral life cycle. The infectious HCV system developed here provides a useful and versatile tool which should greatly facilitate the identification of HCV inhibitors currently not identified by the subgenomic replicon system.
Genome-Scale Genotype-Phenotype Matching of Two
Lactococcus lactis
Isolates from Plants Identifies Mechanisms of Adaptation to the Plant Niche
Authors: Siezen Roland J. , Starrenburg Marjo J. C. , Boekhorst Jos , Renckens Bernadet , Molenaar Douwe , van Hylckama Vlieg Johan E. T.
Published: November 2007

Lactococcus lactis
is a primary constituent of many starter cultures used for the manufacturing of fermented dairy products, but the species also occurs in various nondairy niches such as (fermented) plant material. Three genome sequences of
L. lactis
dairy strains (IL-1403, SK11, and MG1363) are publicly available. An extensive molecular and phenotypic diversity analysis was now performed on two
L. lactis
plant isolates. Diagnostic sequencing of their genomes resulted in over 2.5 Mb of sequence for each strain. A high synteny was found with the genome of
L. lactis
IL-1403, which was used as a template for contig mapping and locating deletions and insertions in the plant
L. lactis
genomes. Numerous genes were identified that do not have homologs in the published genome sequences of dairy
L. lactis
strains. Adaptation to growth on substrates derived from plant cell walls is evident from the presence of gene sets for the degradation of complex plant polymers such as xylan, arabinan, glucans, and fructans but also for the uptake and conversion of typical plant cell wall degradation products such as α-galactosides, β-glucosides, arabinose, xylose, galacturonate, glucuronate, and gluconate. Further niche-specific differences are found in genes for defense (nisin biosynthesis), stress response (nonribosomal peptide synthesis and various transporters), and exopolysaccharide biosynthesis, as well as the expected differences in various mobile elements such as prophages, plasmids, restriction-modification systems, and insertion sequence elements. Many of these genes were identified for the first time in
Lactococcus lactis
. In most cases good correspondence was found with the phenotypic characteristics of these two strains.
Existence of Abnormal Protein Aggregates in Healthy
Escherichia coli
Cells
Authors: Maisonneuve Etienne , Fraysse Laetitia , Moinier Danielle , Dukan Sam
Published: November 2007

Protein aggregation is a phenomenon observed in all organisms and has often been linked with cell disorders. In addition, several groups have reported a virtual absence of protein aggregates in healthy cells. In contrast to previous studies and the expected outcome, we observed aggregated proteins in aerobic exponentially growing and “healthy”
Escherichia coli
cells. We observed overrepresentation of “aberrant proteins,” as well as substrates of the major conserved chaperone DnaK (Hsp70) and the protease ClpXP (a serine protease), in the aggregates. In addition, the protein aggregates appeared to interact with chaperones known to be involved in the aggregate repair pathway, including ClpB, GroEL, GroES, and DnaK. Finally, we showed that the levels of reactive oxygen species and unfolded or misfolded proteins determine the levels of protein aggregates. Our results led us to speculate that protein aggregates may function as a temporary “trash organelle” for cellular detoxification.
Epstein–Barr virus and Burkitt lymphoma
Authors: Brady G , MacArthur G J , Farrell P J
Published: November 2007

Burkitt lymphoma (BL) is an aggressive B-cell malignancy with endemic, sporadic and immunodeficiency-associated variants. It has been known for many years that the fundamental transforming event in BL is the translocation of the MYC gene, and the events that bring about this translocation and those that allow cells to survive with the constitutive expression of MYC have been the subject of intense investigation. Epstein–Barr virus (EBV) infection, malaria, immunodeficiency and spontaneous, somatic mutation can all contribute to the origin and maintenance of this cancer and their mechanisms are the subject of this review.
Hepatitis C virus and lymphoma
Authors: Viswanatha D S , Dogan A
Published: November 2007

Hepatitis C virus (HCV) is well known for its aetiological role in chronic non-A, non-B viral hepatitis, liver cirrhosis and hepatocellular carcinoma; in addition, the virus has also been implicated in a number of extra-hepatic “autoimmune” disease manifestations. A causative association between HCV and non-Hodgkin lymphoma (NHL) was postulated relatively recently and has been the subject of intense investigation, as well as some debate. On the strength of epidemiological data, emerging biological investigations and clinical observations, HCV appears to be involved in the pathogenesis of at least a proportion of patients with NHL. Morphologically, HCV-associated lymphomas represent a variety of histological subtypes including marginal zone lymphoma (splenic, nodal and extranodal), small lymphocytic lymphoma/chronic lymphocytic leukaemia, lymphoplasmacytic lymphoma and diffuse large B-cell lymphoma. Remarkably, some HCV-associated NHL appears to be highly responsive to antiviral therapy, providing some clinical evidence for this relationship, as well as the prospect for novel therapeutic intervention.
WHAT THE INFRARED BEHAVIOR OF QCD VERTEX FUNCTIONS IN LANDAU GAUGE CAN TELL US ABOUT CONFINEMENT
Authors: ALKOFER R. , FISCHER C. S. , LLANES-ESTRADA F. J. , SCHWENZER K.
Published: November 2007

The infrared behavior of Landau gauge QCD vertex functions is investigated employing a skeleton expansion of the Dyson–Schwinger and Renormalization Group equations. Results for the ghost-gluon, three-gluon, four-gluon and quark-gluon vertex functions are presented. Positivity violation of the gluon propagator, and thus gluon confinement, is demonstrated. Results of the Dyson–Schwinger equations for a finite volume are compared to corresponding lattice data. It is analytically demonstrated that a linear rising potential between heavy quarks can be generated by infrared singularities in the dressed quark-gluon vertex. The selfconsistent mechanism that generates these singularities necessarily entails the scalar Dirac amplitudes of the full vertex and the quark propagator. These can only be present when chiral symmetry is broken, either explicitly or dynamically.
GAUGE-INVARIANT SOFT MODES IN YANG–MILLS THEORY
Authors: FORKEL HILMAR
Published: November 2007

A gauge-invariant saddle point expansion for the Yang–Mills vacuum transition amplitude on the basis of the squeezed approximation to the vacuum wave functional is outlined. This framework allows the identification of gauge-invariant infrared degrees of freedom which arise as dominant sets of gauge field orbits and provide the principal input for an essentially analytical treatment of soft amplitudes. The analysis of the soft modes sheds new light on how vacuum fields organize themselves into collective excitations and yields a gauge-invariant representation of instanton and meron effects as well as a new physical interpretation for Faddeev–Niemi knots.
THE 2D GROSS–NEVEU MODEL BEYOND LARGE-N IN THE OPTIMIZED PERTURBATION THEORY
Authors: KNEUR JEAN-LOÏC , PINTO MARCUS BENGHI , RAMOS RUDNEI O.
Published: November 2007

In order to analyze optimization issues related to the non-perturbative optimized perturbation theory method we consider the effective potential as well as the fermionic mass for the 2d Gross–Neveu model. A direct comparison within the large-N approximation shows that the results obtained from the effective potential optimization are more efficient unless one uses the renormalization group to improve the mass.
SLOWLY ROTATING PULSARS
Authors: ALLOY M. D. , MENEZES D. P.
Published: November 2007

In the present work we investigate one possible variation on the usual static pulsars: the inclusion of rotation. We use a formalism proposed by Hartle and Thorne to calculate the properties of rotating pulsars with all possible compositions. All calculations were performed for zero temperature and also for fixed entropy equations of state.
AN EMPIRICAL INVESTIGATION OF METHODS, FOR TEACHING DESIGN PATTERNS WITHIN, OBJECT-ORIENTED FRAMEWORKS
Authors: HO SIN BAN , CHAI IAN , TAN CHUIE HONG
Published: November 2007

Design patterns have become an important part of modern object-oriented design. It is necessary to evaluate and compare the effectiveness of different methods of pedagogical documentation in teaching design patterns. We compared patterns-style documentation with minimalist documentation. Patterns style disagrees with minimalism in that contextual information is not minimal — it usually contains information other than what needs to be done. The discoveries in this empirical study were two fold. First, the MANOVA (multivariate analyses of variance) shows that the effect of patterns-style documentation and minimalism are different. Second, we proposed a prediction model using a regression modeling technique. Considering these results, we formulate some guidelines for effective framework documentation by applying five of the design patterns within the Swing environment as our case study. Different documentation philosophies are better for different goals. For a simple task, use minimalist documentation. For a much more complex problem such involving five of the design patterns, our empirical results suggest using patterns-style documentation.
FEATURE SELECTION VIA LEAST SQUARES SUPPORT FEATURE MACHINE
Authors: LI JIANPING , CHEN ZHENYU , WEI LIWEI , XU WEIXUAN , KOU GANG
Published: November 2007

In many applications such as credit risk management, data are represented as high-dimensional feature vectors. It makes the feature selection necessary to reduce the computational complexity, improve the generalization ability and the interpretability. In this paper, we present a novel feature selection method — "Least Squares Support Feature Machine" (LS-SFM). The proposed method has two advantages comparing with conventional Support Vector Machine (SVM) and LS-SVM. First, the convex combinations of basic kernels are used as the kernel and each basic kernel makes use of a single feature. It transforms the feature selection problem that cannot be solved in the context of SVM to an ordinary multiple-parameter learning problem. Second, all parameters are learned by a two stage iterative algorithm. A 1-norm based regularized cost function is used to enforce sparseness of the feature parameters. The "support features" refer to the respective features with nonzero feature parameters. Experimental study on some of the UCI datasets and a commercial credit card dataset demonstrates the effectiveness and efficiency of the proposed approach.
HETEROCYCLIC HYDROGEN BONDED COMPLEXES INVOLVING THREE AND FIVE MEMBERS: A QUANTUM CHEMICAL STUDY ABOUT THE CASE OF THE NONLINEARITY ON THE HYDROGEN BONDING
Authors: DE OLIVEIRA BOAZ GALDINO , DE ARAÚJO REGIANE DE CÁSSIA MARITAN UGULINO , DE CARVALHO ANTÔNIO BEZERRA , RAMOS MOZART NEVES
Published: November 2007

B3LYP/6-311++G(d,p) and B3LYP/6-31G(d,p) theoretical levels combined with topological calculations based on the theory of atoms in molecules (AIM) were used to study the formation of intermolecular interactions on heterocyclic hydrogen-bonded complexes formed by ethylene oxide, sulfide oxide, 2,5-dihydrofuran, thiophene, and the hydrofluoric acid. As observed, the electrophilic attack of the hydrofluoric acid occur aligned to the n lone pair of the heteroatom of the cyclic systems, the modeled structure of the hydrogen-bonded complexes is interpreted in terms of the intermolecular parameters of the (n ⋯ HF ) hydrogen bond, such as its R(n ⋯ HF ) distance, ΔECbinding energy, and the new υ(n ⋯ HF ) stretching vibrational mode. From these criteria, a relationship between the strength (R, ΔECand υ) of the hydrogen bonds and its nonlinearity deviation was verified, which is formed by a secondary interaction between the hydrofluoric acid and axial hydrogen atoms of the cyclic structure. Moreover, even though the Bader's electronic density partitioning has been projected with low dependence from ab initio wave functions, it is shown here that the 6-31G(d,p) basis sets characterized the secondary interaction in geometrical point of view, as well as by means of the AIM protocol through the specific calculation of bond critical points between the fluoride and the axial hydrogen atoms.
In vivo regulation of phenylalanine hydroxylation to tyrosine, studied using enrichment in apoB-100
Authors: Rafii Mahroukh , McKenzie Jane M. , Roberts Susan A. , Steiner George , Ball Ronald O. , Pencharz Paul B.
Published: November 2007

Phenylalanine hydroxylation is necessary for the conversion of phenylalanine to tyrosine and disposal of excess phenylalanine. Studies of in vivo regulation of phenylalanine hydroxylation suffer from the lack of a method to determine intrahepatocyte enrichment of phenylalanine and tyrosine. apoB-100, a hepatic export protein, is synthesized from intrahepatocyte amino acids. We designed an in vivo multi-isotope study, [15N]phenylalanine and [2H2]tyrosine to determine rates of phenylalanine hydroxylation from plasma enrichments in free amino acids and apoB-100. For independent verification of apoB-100 as a reflection of enrichment in the intrahepatocyte pool, [1-13C]lysine was used as an indicator amino acid (IAA) to measure in vivo changes in protein synthesis in response to tyrosine supplementation. Adult men ( n = 6) were fed an amino acid-based diet with low phenylalanine (9 mg·kg−1·day−1, 4.54 μmol·kg−1·,h−1) and seven graded intakes of tyrosine from 2.5 (deficient) to 12.5 (excess) mg·kg−1·day−1. Gas chromatography-quadrupole mass spectrometry did not detect any tracer in apoB-100 tyrosine. A new and more sensitive method to measure label enrichment in proteins using isotope ratio mass spectrometry demonstrated that phenylalanine hydroxylation measured in apoB-100 decreased linearly in response to increasing tyrosine intake and reached a break point at 6.8 mg·kg−1·day−1. IAA oxidation decreased with increased tyrosine intake and reached a break point at 6.0 mg·kg−1·day−1. We conclude: apoB-100 is an accurate and useful measure of changes in phenylalanine hydroxylation; the synthesis of tyrosine via phenylalanine hydroxylation is regulated to meet the needs for protein synthesis; and that plasma phenylalanine does not reflect changes in protein synthesis.
Gait Variability Is Associated with Subclinical Brain Vascular Abnormalities in High-Functioning Older Adults
Authors: Rosano Caterina , Brach Jennifer , Studenski Stephanie , Longstreth Jr. W.T. , Newman Anne B.
Published: November 2007

Background: Gait variability is an index of how much gait parameters, such as step length, change from one step to the next. Gait variability increases with age and in individuals affected by cortical and subcortical neurodegenerative conditions, and it is associated with falls and incident mobility disability. The brain anatomical correlates of gait variability have not been studied in high-functioning community-dwelling older adults. Methods: Gait variability and brain MRIs were assessed in a cohort of 331 men and women (mean age = 78.3 years) free from stroke, dementia or Parkinson’s disease. Gait variability was computed for spatial parameters (step length and step width) and for temporal parameters (stance time). Subclinical brain vascular abnormalities were measured on brain MRIs as infarcts and white matter hyperintensities. Results: Greater variability of step length was associated with greater prevalence of infarcts, including infarcts in the basal ganglia, and with greater white matter hyperintensities severity, independent of age, gender, cognitive function and cardiovascular disease. Weaker associations were found between the other variability measures and the MRI measures. Conclusion: In this group of older adults free from neurodegenerative diseases, a greater variability of step length was associated with greater burden of subclinical brain vascular abnormalities as defined by MRI.
Brain Injury of the Survivor Diagnosed at 18 Weeks of Gestation after Intrauterine Demise of the Co-Twin: A Case Report
Authors: Morokuma Seiichi , Tsukimori Kiyomi , Anami Ai , Fukushima Kotaro , Morioka Takato , Wake Norio
Published: November 2007

Brain injury in a surviving fetus following the demise of a monochorionic co-twin has only rarely been reported in the first trimester or early second trimester; most documented cases were beyond 20 weeks of gestation.
Platelet-Derived Microparticles and Platelet Count in Preterm Newborns
Authors: Wasiluk Alicja , Mantur Maria , Szczepański Marek , Matowicka-Karna Joanna , Kemona Halina , Warda Janusz
Published: November 2007

Objective: Does formation of platelet-derived microparticles correspond to platelet activation? Methods: The study was performed in 51 preterm newborns, 25 girls and 26 boys. The control group consisted of 55 term newborns, 25 girls and 30 boys. Blood samples were collected from the umbilical artery. The percentage of platelet-derived microparticles and platelet count were determined using flow cytometric analysis based on the CD61-positive antigen. Results: The percentage of platelet-derived microparticles was higher in preterm newborns (5.46) in comparison to term newborns (4.22, p < 0.01). We found 4.61% of platelet-derived microparticles in preterm female newborns and 6.28% in preterm boys (p < 0.0070). The platelet count was 256 × 103 µl in girls and 238 × 103 µl in boys. Female healthy term newborns presented higher values of platelet-derived microparticles (4.4%) than male newborns (4.07%, p = 0.4725, table 1). The platelet count in girls was found to be 308 × 103 µl and in boys 270 × 103 µl. Conclusions: Higher percentage of platelet-derived microparticles in preterm newborns may provide a compensatory mechanism for the hemostatic system.
Early Intraperitoneal Transfusion and Adjuvant Maternal Immunoglobulin Therapy in the Treatment of Severe Red Cell Alloimmunization prior to Fetal Intravascular Transfusion
Authors: Fox C. , Martin W. , Somerset D.A. , Thompson P.J. , Kilby M.D.
Published: November 2007

This descriptive case study documents the treatment of a cohort of 6 women with pregnancies complicated by red cell alloimmunization who in previous pregnancies had objective evidence of severe fetal anemia prior to 20 weeks of gestation, with accompanying high perinatal loss (66% mortality). In the pregnancies described, 5 singletons and 1 dichorionic, diamniotic twin pregnancy underwent alternate week, serial intraperitoneal transfusions between 16 and 21 weeks, until a gestation when classical fetal intravascular transfusions could be commenced. In addition, 4 women consented to have additional, adjuvant maternal intravenous gammaglobulin (IVIG) therapy (0.8 g/kg per week). At the first fetal blood sampling at a median gestational age of 22 weeks (95% CI 21.2–23.4 weeks) the median hemoglobin concentration was 10.1 g% (95% CI 7.4–13.4 g%). In only 2 cases were the fetal hemoglobin levels at fetal blood sampling between –2 SD and –5 SD for gestational age; in 1 case this was associated with fetal mortality. This cohort indicates that such treatment may prevent severe fetal anemia from developing prior to 20 weeks and, in this cohort, indicated an improved survival of pregnancies (86% survival (6/7)), as compared to the previous history. The only perinatal mortality occurred in a growth-restricted fetus whose mother had a chronic opiate addiction. The fetus died prior to 20 weeks. Of the pregnancies that progressed beyond 20 weeks and commenced classical fetal intravascular transfusions, the survival was 100%.
Management of Pregnancy in Adolescence Complicated by Acute Lymphoblastic Leukemia
Authors: Papantoniou Nikolaos , Daskalakis George , Marinopoulos Spyros , Anastasakis Eleftherios , Mesogitis Spyros , Antsaklis Aris
Published: November 2007

The management of the common acute lymphoblastic leukemia in pregnancy has been controversial. We report a case of a 16-year-old primigravida with acute lymphoblastic leukemia, first presented in pregnancy, which was treated with aggressive chemotherapy protocols. Full remission of the disease was achieved. The neonate was born at 32 weeks following a cesarean section. The woman remains in complete remission, continuing maintenance chemotherapy, 18 months following diagnosis. The offspring did not show any abnormality in physical examinations or laboratory tests and keeps growing normally 18 months after birth.
Blood Pressure and Cognition in the Aberdeen 1936 Birth Cohort
Authors: Starr John M. , Deary Ian J. , Fox Helen , Whalley Lawrence J.
Published: November 2007

Background: The relationship between blood pressure and cognition in old age remains unclear. Some data indicate that elevated blood pressure causes cognitive deficits whilst others show that lower early life mental ability predicts high blood pressure in adulthood. Longitudinal studies in which mental ability earlier in life is known are needed to clarify the relationship. Objective: To measure the effect of blood pressure on cognition in late adulthood after adjusting for early life mental ability. Methods: The sample comprised survivors of the 1947 Scottish Mental Survey who had validated IQ scores at age 11. Six cognitive tests – Mini-Mental State Examination, Raven’s Progressive Matrices, Rey Auditory Verbal Learning Test, Uses of Common Objects Test, Digit Symbol Test and Block Design – were administered at ages 64, 66 and 68 years. Sitting and standing blood pressure was also measured at each wave of follow-up. Mixed general linear models were constructed with each cognitive test treated as a repeated measure of an underlying cognitive trait and with wave of testing also set as a repeated measure. Mental ability at age 11 was entered as a covariate. Results: 504 participants were tested at wave 1 with 368 returning at wave 2 and 300 at wave 3. Age 11 mental ability did not predict any of the blood pressure measures. There were several significant associations between blood pressure variables and cognitive test scores in univariate models. After adjusting for significant effects of wave of testing, type of cognitive test, the interaction between these, age 11 mental ability, age, gender and occupation in a multivariate model, the main effect of BP trait was no longer significant (p = 0.44) nor its effect over time (p = 0.26), though there was a significant interaction between blood pressure trait (BP) and test type with a distinctly negative effect of BP on Auditory Verbal Learning Test (p = 0.007, –0.13 points per mm Hg higher, 95% CI –0.22 to –0.033). Conclusion: The effects of blood pressure on cognition in old age are finely nuanced. Multivariate repeated measures models reveal a differential effect of blood pressure on verbal recall.
Dental Findings in Diabetic Adults
Authors: Bakhshandeh S. , Murtomaa H. , Vehkalahti M.M. , Mofid R. , Suomalainen K.
Published: November 2007

The dental status of dentate diabetic adults (n = 299) and its associations with diabetes-related factors was explored in Tehran, Iran. Presence of diabetes-related complications made no difference in mean values of DMFT, but was associated with a higher number of decayed and missing teeth, and fewer filled teeth. Higher level of HbA1c was associated with higher DMFT for men, but not for women. In conclusion, the results suggest a possible association between the level of metabolic control of diabetes mellitus and cumulative caries experience.
The Role of Angiotensin II Receptor-1 Blockade in the Hypoxic Pulmonary Vasoconstriction Response in Newborn Piglets
Authors: Camelo, Jr. José Simon , Hehre Dorothy , Devia Carlos , Camelo Sílvia Helena Henriques , Bancalari Eduardo , Suguihara Cleide
Published: November 2007

Background: Angiotensin-converting enzyme activity is increased in newborn infants with respiratory distress syndrome and in animals with alveolar hypoxia. Objective: To test whether angiotensin II (Ang II) mediates the pulmonary vasoconstriction induced by acute hypoxia in newborn piglets. Methods: Eight unanesthetized chronically instrumented newborn piglets (mean ± SEM; age 6.6 ± 0.6 days; weight 2,181 ± 174 g) were randomly assigned to receive a saline solution or the Ang II type 1 receptor (AT1) antagonist, losartan, in a crossover study design, with an interval of at least 48 h between the first and second study. Pulmonary artery (Ppa), wedge, systemic arterial (Psa) and right atrial pressures, cardiac output (CO), pulmonary (PVR) and systemic (SVR) vascular resistances, and arterial blood gases were obtained in room air, before and during the saline or losartan infusion (6 mg/kg followed by 3 mg/kg/h), and during 6 h of hypoxia (FiO2 = 0.11) and saline or losartan infusion. Data were analyzed by repeated measures analysis of variance. Results: The pulmonary vasoconstriction induced by acute hypoxia was significantly attenuated during losartan infusion, while Psa, SVR, CO, pH, PaCO2, PaO2 and base excess did not differ between groups. During room air, Ppa, PVR, Psa, SVR and CO values were not modified by saline or losartan infusion. Conclusion: These data suggest that the pulmonary vasoconstriction induced by acute hypoxia in newborn piglets is partially mediated by Ang II, acting via AT1.
Altered Plasma Versus Vascular Biopterins in Human Atherosclerosis Reveal Relationships Between Endothelial Nitric Oxide Synthase Coupling, Endothelial Function, and Inflammation
Authors: Antoniades Charalambos , Shirodaria Cheerag , Crabtree Mark , Rinze Ruth , Alp Nicholas , Cunnington Colin , Diesch Jonathan , Tousoulis Dimitris , Stefanadis Christodoulos , Leeson Paul , Ratnatunga Chandi , Pillai Ravi , Channon Keith M.
Published: November 2007

Background—

Tetrahydrobiopterin (BH
4
) is a key regulator of endothelial nitric oxide synthase (eNOS) activity and coupling. However, the extent to which vascular and/or systemic BH
4
levels are altered in human atherosclerosis and the importance of BH
4
bioavailability in determining endothelial function and oxidative stress remain unclear. We sought to define the relationships between plasma and vascular biopterin levels in patients with coronary artery disease and to determine how BH
4
levels affect endothelial function, eNOS coupling, and vascular superoxide production.

Methods and Results—

Samples of saphenous veins and internal mammary arteries were collected from 219 patients with coronary artery disease undergoing coronary artery bypass grafting. We determined plasma and vascular levels of biopterins, vasomotor responses to acetylcholine, and vascular superoxide production in the presence and absence of the eNOS inhibitor
N
G
-nitro-
l
-arginine methyl ester. High vascular BH
4
was associated with greater vasorelaxations to acetylcholine (
P
<0.05), whereas high plasma BH
4
was associated with lower vasorelaxations in response to acetylcholine (
P
<0.05). Furthermore, an inverse association was observed between plasma and vascular biopterins (
P
<0.05 for both saphenous veins and internal mammary arteries). High vascular (but not plasma) BH
4
was associated with reduced total and
N
G
-nitro-
l
-arginine methyl ester–inhibitable superoxide, suggesting improved eNOS coupling. Finally, plasma but not vascular biopterin levels were correlated with plasma C-reactive protein levels (
P
<0.001).

Conclusions—

An inverse association exists between plasma and vascular biopterins in patients with coronary artery disease. Vascular but not plasma BH
4
is an important determinant of eNOS coupling, endothelium-dependent vasodilation, and superoxide production in human vessels, whereas plasma biopterins are a marker of systemic inflammation.
Endogenous Testosterone and Mortality Due to All Causes, Cardiovascular Disease, and Cancer in Men
Authors: Khaw Kay-Tee , Dowsett Mitch , Folkerd Elizabeth , Bingham Sheila , Wareham Nicholas , Luben Robert , Welch Ailsa , Day Nicholas
Published: November 2007

Background—

The relation between endogenous testosterone concentrations and health in men is controversial.

Methods and Results—

We examined the prospective relationship between endogenous testosterone concentrations and mortality due to all causes, cardiovascular disease, and cancer in a nested case-control study based on 11 606 men aged 40 to 79 years surveyed in 1993 to 1997 and followed up to 2003. Among those without prevalent cancer or cardiovascular disease, 825 men who subsequently died were compared with a control group of 1489 men still alive, matched for age and date of baseline visit. Endogenous testosterone concentrations at baseline were inversely related to mortality due to all causes (825 deaths), cardiovascular disease (369 deaths), and cancer (304 deaths). Odds ratios (95% confidence intervals) for mortality for increasing quartiles of endogenous testosterone compared with the lowest quartile were 0.75 (0.55 to 1.00), 0.62 (0.45 to 0.84), and 0.59 (0.42 to 0.85), respectively (
P
<0.001 for trend after adjustment for age, date of visit, body mass index, systolic blood pressure, blood cholesterol, cigarette smoking, diabetes mellitus, alcohol intake, physical activity, social class, education, dehydroepiandrosterone sulfate, androstanediol glucuronide, and sex hormone binding globulin). An increase of 6 nmol/L serum testosterone (≈1 SD) was associated with a 0.81 (95% confidence interval 0.71 to 0.92,
P
<0.01) multivariable-adjusted odds ratio for mortality. Inverse relationships were also observed for deaths due to cardiovascular causes and cancer and after the exclusion of deaths that occurred in the first 2 years.

Conclusions—

In men, endogenous testosterone concentrations are inversely related to mortality due to cardiovascular disease and all causes. Low testosterone may be a predictive marker for those at high risk of cardiovascular disease.
Metaphor and the Logicians from Aristotle to Cajetan
Authors: Ashworth E. Jennifer
Published: November 2007

I examine the treatment of metaphor by medieval logicians and how it stemmed from their reception of classical texts in logic, grammar, and rhetoric. I consider the relation of the word 'metaphor' to the notions of translatio and transumptio, and show that it is not always synonymous with these. I also show that in the context of commentaries on the Sophistical Refutations metaphor was subsumed under equivocation. In turn, it was linked with the notion of analogy not so much in the Greek sense of a similarity between two proportions or relations as in the new medieval sense of being said secundum prius et posterius. Whether or not analogy could be reduced to metaphor, or the reverse, depended on the controversial issue of the number of acts of imposition needed to produce an equivocal term. A spectrum of views is canvassed, including those found in the logic commentaries of John Duns Scotus.
The Strategic Entry of China's Emerging Multinationals into Africa
Authors: Corkin Lucy
Published: November 2007

China's relations with Africa have grown exponentially over the past decade. During the 1990s, Sino-African trade grew by 700 per cent and many high-level visits occurred from 1995. China's heightened political interest in Africa has paved the way for the entry of Chinese companies of all sectors into Africa's economies. The entry of Chinese companies into Africa, largely state-directed in nature, is spurred on by the need for energy security and new markets, as well as specifically political objectives. Their engagement in Africa, though not without its challenges, has the potential to benefit both African countries and Chinese commercial interests.