bluuebunny/crossref_metadata_2025 huggingface dataset:
Sensitive ELISA detection of amyloid‐β protofibrils in biological samples
Authors: Englund Hillevi , Sehlin Dag , Johansson Ann‐Sofi , Nilsson Lars N. G. , Gellerfors Pär , Paulie Staffan , Lannfelt Lars , Pettersson Frida Ekholm
Published: July 2007

Amyloid‐β (Aβ) protofibrils are known intermediates of the in vitro Aβ aggregation process and the protofibrillogenic Arctic mutation (APPE693G) provides clinical support for a pathogenic role of Aβ protofibrils in Alzheimer’s disease (AD). To verify their in vivo relevance and to establish a quantitative Aβ protofibril immunoassay, Aβ conformation dependent monoclonal antibodies were generated. One of these antibodies, mAb158 (IgG2a), was used in a sandwich ELISA to specifically detect picomolar concentrations of Aβ protofibrils without interference from Aβ monomers or the amyloid precursor protein (APP). The specificity and biological significance of this ELISA was demonstrated using cell cultures and transgenic mouse models expressing human APP containing the Swedish mutation (APPKN670/671ML), or the Swedish and Arctic mutation in combination. The mAb158 sandwich ELISA analysis revealed presence of Aβ protofibrils in both cell and animal models, proving that Aβ protofibrils are formed not only in vitro, but also in vivo. Furthermore, elevated Aβ protofibril levels in the Arctic‐Swedish samples emphasize the usefulness of the Arctic mutation as a model of enhanced protofibril formation. This assay provides a novel tool for investigating the role of Aβ protofibrils in AD and has the potential of becoming an important diagnostic assay.
Functional insights on the polarized redistribution of leukocyte integrins and their ligands during leukocyte migration and immune interactions
Authors: Barreiro Olga , De La Fuente Hortensia , Mittelbrunn María , Sánchez‐Madrid Francisco
Published: July 2007

Summary:  Cell–cell and cell–matrix interactions are of critical importance in immunobiology. Leukocytes make extensive use of a specialized repertoire of receptors to mediate such processes. Among these receptors, integrins are known to be of crucial importance. This review deals with the central role of integrins and their counterreceptors during the establishment of leukocyte–endothelium contacts, interstitial migration, and final encounter with antigen‐presenting cells to develop an appropriate immune response. Particularly, we have addressed the molecular events occurring during these sequential processes, leading to the dynamic subcellular redistribution of adhesion receptors and the reorganization of the actin cytoskeleton, which is reflected in changes in cytoarchitecture, including leukocyte polarization, endothelial docking structure formation, or immune synapse organization. The roles of signaling and structural actin cytoskeleton‐associated proteins and organized membrane microdomains in the regulation of receptor adhesiveness are also discussed.
Signaling by small GTPases in the immune system
Authors: Scheele Juergen S. , Marks Reinhard E. , Boss Gerry R.
Published: July 2007

Summary:  The Ras superfamily consists of over 50 low‐molecular‐weight proteins that cycle between an inactive guanosine diphosphate‐bound state and an active guanosine triphosphate (GTP)‐bound state. They are involved in a variety of signal transduction pathways that regulate cell growth, intracellular trafficking, cell migration, and apoptosis. Several methods have been devised to measure the activation state of Ras proteins, defined as the percent of Ras molecules in the active GTP‐bound state. We have previously developed a quantitative biochemical method that can be applied to animal and human tissues and have used it to measure the activation state of Ras, Rap1, Rheb, and Rho proteins in cultured cells and in animal and human tumors. Ras, Rac, and Rho all play roles in regulating the functions of T and B lymphocytes and dendritic cells, and these proteins are clearly important in maintaining normal immune system function.
Tec kinases, actin, and cell adhesion
Authors: Gomez‐Rodriguez Julio , Readinger Julie A. , Viorritto Irene C. , Mueller Kristen L. , Houghtling Richard A. , Schwartzberg Pamela L.
Published: July 2007

Summary:  The Tec family non‐receptor tyrosine kinases have been recognized for their roles in the regulation of phospholipase C‐γ and Ca2+ mobilization downstream from antigen receptors on lymphocytes. Recent data, however, show that the Tec family kinase interleukin‐2‐inducible T‐cell kinase (Itk) also participates in pathways regulating the actin cytoskeleton and ‘inside‐out’ signaling to integrins downstream from the T‐cell antigen receptor. Data suggest that Itk may function in a kinase‐independent fashion to regulate proper recruitment of the Vav1 guanine nucleotide exchange factor. By enhancing actin cytoskeleton reorganization, recruitment of signaling molecules to the immune synapse, and integrin clustering in response to both antigen and chemokine receptors, the Tec kinases serve as modulators or amplifiers that can increase the duration of T‐cell signaling and regulate T‐cell functional responses.
Ca2+ signaling in antigen receptor‐activated B lymphocytes
Authors: Engelke Michael , Engels Niklas , Dittmann Kai , Stork Björn , Wienands Jürgen
Published: July 2007

Summary:  B cells respond to antigen stimulation with mobilization of the Ca2+ second messenger in two phases operated by two distinct sets of effector proteins. First, an antigen receptor‐specific Ca2+ initiation complex is assembled, activated, and targeted to the plasma membrane to trigger the transient release of Ca2+ from intracellular stores of the endoplasmic reticulum. Second, more ubiquitously expressed Ca2+ channels of the plasma membrane are opened to allow for sustained Ca2+ influx from the extracellular medium. Depending on the developmental stage of the B cell, the kinetics and profile of the two phases are adjusted at multiple levels of positive and negative regulation. A molecular basis for the Ca2+ signaling plasticity is provided by cytosolic and transmembrane adapter proteins. They act as signal organizers, which control enzyme/substrate interactions by directing the different signaling modules into specific subcellular compartments. These arrangements orchestrate a graduated activation of Ca2+‐sensitive downstream pathways, which ultimately determine appropriate cellular responses, namely elimination of autoreactive B cells or proliferation and differentiation of immunocompetent B cells into antibody‐secreting plasma cells.
Guanine nucleotide exchange factors of the cytohesin family and their roles in signal transduction
Authors: Kolanus Waldemar
Published: July 2007

Summary:  Members of the cytohesin protein family, a group of guanine nucleotide exchange factors for adenosine diphosphate ribosylation factor (ARF) guanosine triphosphatases, have recently emerged as important regulators of signal transduction in vertebrate and invertebrate biology. These proteins share a modular domain structure, comprising carboxy‐terminal membrane recruitment elements, a Sec7 homology effector domain, and an amino‐terminal coiled‐coil domain that serve as a platform for their integration into larger signaling complexes. Although these proteins have a highly similar overall build, their individual biological functions appear to be at least partly specific. Cytohesin‐1 had been identified as a regulator of β2 integrin inside‐out regulation in immune cells and was subsequently shown to be involved in mitogen‐associated protein kinase signaling in tumor cell proliferation as well as in T‐helper cell activation and differentiation. Cytohesin‐3, which had been discovered to be strongly associated with T‐cell anergy, was very recently described as an essential component of insulin signal transduction in Drosophila and in human and murine liver cells. Future work will aim to dissect the mechanistic details of the modes of action of the cytohesins as well as to define the precise roles of these versatile proteins in vertebrates at the genetic level.
Regulation of T‐cell antigen receptor‐mediated inside‐out signaling by cytosolic adapter proteins and Rap1 effector molecules
Authors: Ménasché Gaël , Kliche Stefanie , Bezman Natalie , Schraven Burkhart
Published: July 2007

Summary:  Integrins are critical for the migration of T cells to lymphoid organs and to sites of inflammation and are also necessary for productive interactions between T cells and antigen‐presenting cells. Integrin activation is enhanced following T‐cell receptor (TCR) engagement, as signals initiated by the TCR increase affinity and avidity of integrins for their ligands. This process, known as inside‐out signaling, has been shown to require several molecular components including the cytosolic adapter proteins adhesion and degranulation‐promoting adapter protein and Src homology 2 domain‐containing adapter protein of 55 kDa, the low molecular weight guanosine triphosphatase Rap1, and the Rap1 effector proteins Rap1 guanosine triphosphate‐interacting adapter molecule, regulator of adhesion and cell polarization enriched in lymphoid tissues, and protein kinase D1. Herein, we review recent findings about how the TCR is linked to integrin activation through inside‐out signaling.
Agricultural wastes as dairy feed in Chiang Mai
Authors: SRUAMSIRI Sompong
Published: July 2007

Dairy farming in Chiang Mai was established in 1965 by the Thai–German Dairy Project and was subsequently taken over by Department of Livestock development in 1970. Starting from 1979, the Dairy Farming Promotion Organization of Thailand also supports the development of dairy farming in northern Thailand. However, dairy farming in Chiang Mai still faces numerous problems. At present, farm sizes are relatively medium, with an average of 23.75 cattle/farm (cows, heifers and calves). Almost all dairy farmers are member of a dairy co‐operative that provides them with an artificial insemination service, supplies of concentrated feed, loans and a center for collecting milk. The average pasture area is 0.3 ha/farm. The main feed resources are green forage from the farm pasture, public areas and roadside pastures, which are abundant only in the rainy season. The farmers are forced to use crop by‐products as roughage in the dry season, especially rice straw, even though its nutritive value is limited due to its low digestibility, low nitrogen and low mineral and vitamin content. To improve the nutritional value of crop by‐products, physical and chemical treatments are implemented. Agro‐industrial wastes such as pineapple waste, sugarcane molasses, the peel, husk or silk of sweet corn and baby corn are also used as dairy feed.
Substitution of plant protein for fish meal in the diet of laying ducks
Authors: THONGWITTAYA Narin
Published: July 2007

Fish meal is a good source of protein feed that can be used to get a high production yield even though it has a comparatively higher price. Plant protein has been found to substitute for fish meal without any adverse effect on production as well as helping to reduce feed cost. Moreover, it is not necessary for a level more than 5% fish meal in the diet of laying ducks. One type of plant protein is soybean meal, considered one of the most valuable sources of vegetable protein and whose amino acid composition is comparable to that of milk protein. In a soybean meal, the first limiting amino acid is methionine. Soybean meal can substitute for fish meal in laying ducks' diet but supplementation of methionine and lysine is recommended. Since sesame meal is rich in methionine and agrinine, 50% of soybean meal can be replaced by sesame meal without adverse effects. Leucaena leaf meal is also a valuable source of protein (26%) and carotenoids but it also has a toxic amino acid (mimosine). However, soaking leucaena leaf meal in water can remove the toxic amino acid and can be used, together with added methionine and lysine, as 10% of the diet for laying ducks.
Accounting for heterogeneity of variances to improve the precision of QTL mapping in dairy cattle
Authors: LIU Yuefu , JANSEN Gerald B. , LIN Ching Y.
Published: July 2007

The principle of interval mapping for quantitative trait loci (QTL) was originally developed for the analysis of single backcross data but it has been increasingly applied to more complicated experimental designs and data structures. It is important to study whether accounting for the heterogeneity of variance would improve the precision of QTL mapping based on data of multiple populations or families. This study compared homogeneous and heterogeneous maximum likelihood approaches for QTL mapping. The data consisted of 433 sons from six sire families with 69 microsatellite markers distributed over 12 chromosomes. The results of this study indicate that the heterogeneous approach generally produced a smaller residual variance and thus provided a better fit to the data than the homogeneous approach, meaning that the heterogeneous approach offers better precision in estimating both positions and effects of QTL. The results further showed that accounting for the heterogeneity of residual variance led to different statistical inferences from ignoring the heterogeneity of variance in QTL mapping. The heterogeneous approach is useful for QTL mapping based on the joint data of diverse reference populations or heteroscedastic data obtained from crossing animals with different genetic backgrounds.
Effects of lauric acid on physical, chemical and microbial characteristics in the rumen of steers on a high grain diet
Authors: YABUUCHI Yuki , TANI Masahide , MATSUSHITA Yoji , OTSUKA Hiroshi , KOBAYASHI Yasuo
Published: July 2007

The effects of being fed lauric acid on rumen characteristics were evaluated in a double 3 × 3 Latin square design using six Holstein steers with ruminal cannulas on a high grain diet. The steers were fed commercial concentrate (8.7 kg/day/steer) with one of three levels of lauric acid (0, 25 or 50 g/day/steer) and timothy hay (1.8 kg/day/steer). The feed intake and digestibility were determined. Ruminal fluid was collected at 3 h after feeding to determine chemical, physical and microbial parameters. An in vitro pure culture study was performed to determine the effects of lauric acid on Streptococcus bovis, a potent bloat‐ and acidosis‐promoting rumen bacterium. There were no differences in feed intake and digestibility among the treatments. The proportion of butyrate and the viscosity of the rumen fluid tended to be lowered (P < 0.08 and P < 0.09, respectively) and the stable ingesta volume increase was significantly decreased (P < 0.01) by the lauric acid feed. The abundance of protozoa and bacteria did not differ among the treatments. In the in vitro study, the growth of S. bovis was inhibited by the lauric acid (100 nmol/L) but it showed an adaptive growth to lauric acid in long‐term subculturing. The S. bovis that had adapted to lauric acid showed decreased viscosity and lactate production (P < 0.01) in culture with sucrose. These results indicate that supplemental lauric acid added to a high grain diet improves physical properties, possibly by altering the metabolic activity of S. bovis, and it may prevent the occurrence of feedlot bloat and acidosis in beef cattle.
Effect of organic acids on the microbial quality of Taiwanese‐style sausages
Authors: WAN Tien‐Chun , LIN Liang‐Chuan , SAKATA Ryoichi
Published: July 2007

The effects of organic acids on the microbial quality of Taiwanese‐style sausages were studied. Pork meat from a Taiwan retail market was decontaminated with various organic acids (citric, lactic and tartaric acid), then, the raw meat was used to make Taiwanese‐style sausages and stored from 0 to 40 days at 4°C. The total plate counts, lactic acid bacteria, Micrococcus, Listeria monocytogenes, Hunter‐L and Hunter‐a values were determined. The total plate counts of the control group were initially greater than those of the treated groups. Higher incidence rates of L. monocytogenes in the products were obtained from the control group, but were not detected in the treated groups during storage. Lactic acid bacteria counts following the lactic acid treatment were lower than those of the other groups. Micrococcus counts of the controls increased by 0.6–1.2 log10 colony‐forming unit (CFU)/g greater than those of treated groups throughout storage at 4°C. The light color (L‐value) of the control group gradually decreased during storage. Pork meat dipped in various organic acids was found to be suitable to extend the shelf‐life and improve the microbiological quality of Taiwanese‐style sausages.
Evaluating environmental impacts of the Japanese beef cow–calf system by the life cycle assessment method
Authors: OGINO Akifumi , ORITO Hideki , SHIMADA Kazuhiro , HIROOKA Hiroyuki
Published: July 2007

The objectives of this study were to evaluate the environmental impacts of a beef cow–calf system using a life cycle assessment (LCA) method and to investigate the effects of scenarios to reduce environmental impacts on the LCA results. The functional unit was defined as one marketed beef calf, and the processes associated with the cow–calf life cycle, such as feed production, feed transport, animal management, the biological activity of the animal and the treatment of cattle waste were included in the system boundary. The present results showed that the total contributions of one beef calf throughout its life cycle to global warming, acidification, eutrophication and energy consumption were 4550 kg of CO2 equivalents, 40.1 kg of SO2 equivalents, 7.0 kg of phosphate (PO4) equivalents and 16.1 GJ, respectively. The contribution of each process to the total environmental impact in each environmental impact category showed a similar tendency to the contribution of each process in each environmental category reported in the case of the beef fattening system as a whole. The results from this analysis showed that shortening calving intervals by 1 month reduced environmental impacts by 5.7–5.8% in all the environmental impact categories examined in the current study, and increasing the number of calves per cow also reduced environmental impacts in all the categories, although the effects were smaller.
Prediction of yield of retail cuts for native and crossbred Chinese Yellow cattle
Authors: CHEN Yinji , LI Chunbao , LIU Li , ZHOU Guanghong , XU Xinglian , GAO Feng
Published: July 2007

Seven hundred and three native and crossbred Chinese Yellow cattle (mean live weight: 523 ± 38 kg) were slaughtered, chilled and segmented. The hot carcass weight (HCW, kg), fat thickness (FT, cm) and rib eye area (REA, cm2) were measured to predict weights and percentages of beef cattle retail cuts. A correlation analysis showed that the HCW and REA were positively correlated with the weights of the total retail cuts (TRC, kg), top grade retail cuts, prime retail cuts and percentage of total carcass weight. A regression analysis indicated that HCW and REA were the best predictors for the weight of total retail cuts (Y = −16.71 + 0.382 HCW + 0.593 REA), and the HCW explained more of the variation than REA. Meanwhile, HCW and REA accounted for 62% of the variation of percentage of total retail cuts (Y = 43.24 − 0.025 HCW + 0.170 REA), whereas the REA was more valuable than the HCW. The FT contributed little in estimating weight or percentage of retail cuts.
Three‐dimensional reconstruction of intramuscular collagen networks of bovine muscle: A demonstration by an immunohistochemical/confocal laser‐scanning microscopic method
Authors: NAKAMURA Yoshi‐Nori , IWAMOTO Hisao , YAMAGUCHI Takahiro , ONO Yoshitaka , NAKANISHI Yoshitaka , TABATA Shoji , NISHIMURA Shotaro , GOTOH Takafumi
Published: July 2007

We undertook a three‐dimensional reconstruction of intramuscular collagen networks of bovine muscle using an immunohistochemical/confocal laser‐scanning microscopic method. By immunohistochemical staining, type I and III collagens were observed mainly in the perimysium, while type IV collagen was observed in the endomysium. On the other hand, type V and VI collagens were observed in both the perimysium and endomysium. By confocal laser‐scanning microscopy, the collagen observed in the perimysium was three‐dimensionally reconstructed as plate‐shaped layers whereas the collagen observed in the endomysium surrounded myofibers. The three‐dimensionally reconstructed observations using immunohistochemical/confocal laser‐scanning microscopic method is useful for investigating collagen networks in muscle.
The Impact of Body Awareness on Sexual Arousal in Women with Sexual Dysfunction
Authors: Seal Brooke N. , Meston Cindy M.
Published: July 2007

Introduction

The impact of self-awareness during sexual activity has been widely discussed. However, research has been largely focused on the effects of performance anxiety in male erectile functioning. It has been suggested that physical appearance concerns may have a similar influence on sexual function in women as does men's self-awareness about erectile function. However, the role that physical appearance or awareness of one's body may play in female sexual response has received little empiric attention.

Aim

To examine the effects of body awareness and self-report levels of body esteem on sexual response in 21 sexually dysfunctional women.

Methods

Body awareness was induced in one of two counterbalanced sessions. A full-length mirror was placed in front of participants throughout the experimental session, and participants were instructed to use the mirror to place 10 electrodes on each side of their bodies to prepare for a possible electrocardiogram. This methodology was used to ensure that women looked at themselves in the mirror and became more aware of their bodies during the experimental session.

Main Outcome Measures

Self-reported mental arousal, perceptions of physical arousal, physiological sexual arousal, affect, anxiety, and cognitive distraction responses to erotica.

Results

Results showed that subjective mental sexual arousal and perceptions of physical sexual arousal increased in response to erotica in the Body Awareness condition compared to in the No Body Awareness condition. These results were not accounted for by level of body esteem. There were no changes in physiological sexual arousal, affect, anxiety, or level of cognitive distraction across the two conditions.

Conclusions

Findings suggest that awareness of one's body is related to increased subjective sexual response in conditions where cognitive distraction does not occur. It is particularly noteworthy that the current sample was made up of sexually dysfunctional women, all of whom had relatively low body image.
NCEP-ATPIII-Defined Metabolic Syndrome, Type 2 Diabetes Mellitus, and Prevalence of Hypogonadism in Male Patients with Sexual Dysfunction
Authors: Corona Giovanni , Mannucci Edoardo , Petrone Luisa , Balercia Giancarlo , Paggi Francesca , Fisher Alessandra D. , Lotti Francesco , Chiarini Valerio , Fedele Domenico , Forti Gianni , Maggi Mario
Published: July 2007

Introduction

Type 2 diabetes mellitus (T2DM) and metabolic syndrome (MetS) are characterized by insulin resistance and often associated with male hypogonadism.

Aim

To discriminate the specific contribution of T2DM and MetS to male hypogonadism.

Methods

A consecutive series of 1,134 (mean age 52.1 ± 13 years) male patients with sexual dysfunction was studied.

Main Outcome Measures

Several hormonal and biochemical parameters were studied along with ANDROTEST, a 12-item validated structured interview, specifically designed for the screening of hypogonadism (total testosterone [TT] <10.4 nmol/L or free testosterone [FT] <37 pmol/L) in a male population with sexual dysfunction.

Results

Irrespective of the criteria used to define hypogonadism, MetS was associated with a significantly higher prevalence of the condition, both in subjects with and without T2DM (41% and 29% vs. 13.2% and 77.1% and 58% vs. 40.6%, respectively, for TT and FT in patients with MetS and with or without T2DM, when compared with subjects without MetS and T2DM; both P  < 0.0001). Conversely, T2DM was associated with a higher prevalence of hypogonadism in subjects with MetS but not in those without MetS. Patients with MetS, with or without T2DM, also showed a higher ANDROTEST score when compared with patients without MetS. Logistic multivariate regression analysis, incorporating the five components of MetS, identified a significant association of elevated waist circumference and hypertriglyceridemia with hypogonadism both in patients, with or without T2DM.

Conclusions

Our study demonstrated that MetS, and in particular visceral adiposity (as assessed by increased waistline and hypertriglyceridemia), is specifically associated with hypogonadism in subjects consulting for sexual dysfunction.
Integrated Sildenafil and Cognitive-Behavior Sex Therapy for Psychogenic Erectile Dysfunction: A Pilot Study
Authors: Banner Linda L. , Anderson Rodney U.
Published: July 2007

Introduction

Men with psychogenic erectile dysfunction (ED) present a challenge to physicians. Treatment with pharmacological agents alone does not address the complexities of the causative or resulting psychological issues.

Aim

To evaluate the effectiveness of an integrative treatment protocol (ITP) with sildenafil and cognitive-behavior sex therapy (CBST) compared with sildenafil alone for men with psychogenic ED.

Main Outcome Measures

Change from baseline on the International Index of Erectile Function (IIEF) in the domains of erectile function and sexual satisfaction to demonstrate improved sexual functioning and confidence.

Methods

Men with psychogenic ED and female partners were randomized to receive either sildenafil alone or an ITP with sildenafil and CBST for the first 4 weeks. In the last 4 weeks, couples in the sildenafil group added CBST sessions to their regimen; patients in the ITP group continued the combined therapy. The IIEF questionnaire was used to compare erectile function and overall satisfaction serially at pretreatment, 4, and 8 weeks. Couples who met the success criteria in both domains after the first 4 weeks received no further treatment.

Results

Fifty-three couples constituted the study population. After the first 4 weeks of sildenafil and ITP, 48% of men met criteria for success on erectile function and 65.5% for satisfaction compared to men on sildenafil alone with 29% and 37.5% success rates, respectively. After the last 4 weeks, integration of CBST with sildenafil resulted in a 58% success rate for erectile function which was comparable to the 66% rate for the initial drug/ITP group; satisfaction rates for men were 45% and 75%, respectively.

Conclusions

CBST was shown to have a positive influence when used throughout the entire 8 weeks of the ITP or added to the sildenafil in the last 4 weeks. Although patients in both treatment regimens had significant improvements in the IIEF domain scores confirming efficacy of sildenafil, those in the CBST and drug regimen achieved higher rates of clinical success within the first 4 weeks of therapy.
Transport Properties of the Binary Type I Clathrate K8Ge44□2
Authors: Beekman Matt , Nolas George S.
Published: July 2007

We report the synthesis and low‐temperature electrical resistivity, Seebeck coefficient, and thermal conductivity of the binary type I clathrate K8Ge44□2 (□=Ge framework vacancy). Electrical resistivity measurements indicated metallic or heavily doped semiconductor behavior, while the Seebeck was relatively high at −77 μV/K at room temperature. The thermal conductivity was very low, on the order of 1 W/m K at room temperature. This work is part of a continuing effort to investigate new compositions in open‐structured and guest‐framework materials for potential thermoelectric applications.
Tailoring the Microwave Dielectric Properties of MgNb2O6 and Mg4Nb2O9 Ceramics
Authors: Abdul Khalam Lamrath , Thomas Sherin , Sebastian Mailadil T.
Published: July 2007

The columbites MgNb2O6, MgTa2O6, and corundum‐type Mg4Nb2O9 ceramics were prepared by the conventional solid‐state ceramic route. The structure and microstructure of the sintered samples were investigated by X‐ray diffraction and scanning electron microscopic techniques. The microwave dielectric properties of the samples were measured by the resonance method in the frequency range 4–6 GHz. The dielectric properties have been tailored by forming a solid solution between MgNb2O6 and MgTa2O6 and by the substitution of TiO2 for Nb2O5 in both MgNb2O6 and Mg4Nb2O9 ceramics. The Mg(Nb0.7Ta1.3)O6 has ɛr=29, Qu×f=67 800 GHz, and τf=0.8 ppm/°C and the MgO–(0.4)Nb2O5–(1.5)TiO2 composition has ɛr=34.5, Qu×f=81 300 GHz, and τf=−2 ppm/°C.
Synthesis of Hydroxyapatite During Glassy Matrix Dissolution: Influence of their Chemical Composition
Authors: Gauthier Arnaud , Thomassin Jean‐Hugues
Published: July 2007

Experimental alteration of synthetic Ca–Si–P glasses was performed in pure water at 90°C from 1 to 56 days. The secondary phases formed during this alteration were analyzed by powder X‐ray diffraction, scanning electron microscopy, and transmission electron microscopy. Changes in the chemical composition of solutions during the reaction were also measured. The results revealed the growth of hydroxyapatite on the glass surfaces, especially for the most calcic of them. Moreover, the stability of the glasses during an alteration process directly depended on their chemical compositions; the more siliceous glasses appeared to be the less alterable matrices. Thus, the development of hydroxyapatite crystals may be experimentally controlled by the chemistry of the starting glassy materials.
Nondestructive Evaluation and Mechanical Characterization of a Defect‐Embedded Ceramic Matrix Composite Laminate
Authors: Mei Hui , Xu Yongdong , Cheng Laifei , Zhang Litong
Published: July 2007

A C/SiC composite panel with defects of known size and of familiar nature was manufactured successfully for nondestructive evaluation. A computed tomography (CT) system was used to detect embedded defects. The results show that CT imaging corresponds well with the designed defects. The defect‐embedded composites undergo relatively greater loss in tensile strength and failure strain than the as‐received samples, although their initial Young's moduli are almost identical. It is also observed that the embedded defects make a significant contribution toward the initiation and accumulation of the damage in the composites, which result eventually in the early failure of the composite.
Interferon and lamivudine monotherapy on chronic hepatitis B in Japan
Authors: Suzuki Fumitaka , Kumada Hiromitsu
Published: July 2007

Aim:  We show data of interferon (IFN) and lamivudine monotherapy on chronic hepatitis B in Japan.

Methods:  Data collected from sixty‐six chronic hepatitis B (CHB) Japanese patients who were treated with IFN for 6 months were analyzed. The efficacy of long‐term IFN therapy in 52 patients with e‐antigen positive CHB, and data from 290 chronically HBV‐infected patients who were treated with lamivudine for more than 3 years, were analyzed.

Results:  Six‐month IFN therapy: among 45 patients with HBeAg at commencement of IFN therapy, nine (20%) were responders. Young patients especially those with high serum alanine aminotransferase (ALT) levels were much more likely to respond to IFN therapy. Twelve‐month IFN therapy: theresponse rate was 31% among 52 patients with HBeAg. Long‐term lamivudine therapy: YMDD motif mutation was detected in 167 of 290 patients (58%) during lamivudine treatment. Breakthrough hepatitis from lamivudine resistant virus was detected in 93 of 290 patients (32%). Finally, 813 patients were treated by lamivudine between September 1995 and February 2006. Fifteen patients lost HBsAg during and after lamivudine therapy.

Conclusion:  Long‐term interferon therapy has a better response than short‐term interferon therapy. Some patients lost HBsAg during and after lamivudine therapy.
Combination therapy with lamivudine and HB vaccine on chronic hepatitis B
Authors: Ishikawa Tetsuya , Kakumu Shinichi
Published: July 2007

Background and aim:  Lamivudine (LAM) has problems of breakthrough hepatitis (BTH) and post‐treatment relapse despite its significant effect for suppressing hepatitis B virus (HBV) replication. In order to find solutions for the problems, the efficacy of combination therapy of LAM plus hepatitis B (HB) vaccine in patients with chronic HBV infection was assessed.

Patients and methods:  Fifty‐three patients with chronic hepatitis B, 33 hepatitis B e‐antigen positive (HBeAg+), and 20 HBeAg negative (HBeAg–) patients, were enrolled in the study, and randomized to receive either LAM monotherapy or combination therapy of LAM and HB vaccine. In the combination therapy group, 100 mg/day of LAM was administered as a baseline therapy, and 10 μg of HB vaccine was injected subcutaneously every month starting at 2 months after LAM administration, six times in total.

Results:  HBeAg negative patients responded well to LAM therapy, and there were no significant differences in short‐term effects between the two therapy groups. With regard to the ratio of developing BTH, there was no difference betweenthe two groups. In HBeAg+ patients, HBV replication was suppressed more efficiently in the combination therapy group than in the monotherapy group. The ratio of developing BTH was significantly lower in the combination therapy group than in the monotherapy group. Regardless of HBeAg serologic status or therapy protocols, post‐treatment relapse was seen in most patients when the administrations of LAM were discontinued. No adverse effect with the use of HB vaccine was observed in all the patients treated with the combination therapy.

Conclusion:  Combination therapy of LAM and HB vaccine is a safe and effective way to control HBV replication and prevent the development of BTH especially in patients with high viral load. However, further study is required in order to achieve the continuous suppression of HBV replication even after cessation of LAM.
In Vitro Suppression of K65R Reverse Transcriptase-Mediated Tenofovir- and Adefovir-5′-Diphosphate Resistance Conferred by the Boranophosphonate Derivatives
Authors: Frangeul Antoine , Barral Karine , Alvarez Karine , Canard Bruno
Published: July 2007

9-[2-(Boranophosphonomethoxy)ethyl]adenine diphosphate (BH3-PMEApp) and (R)-9-[2-(boranophosphonomethoxy)propyl]adenine diphosphate (BH3-PMPApp), described here, represent the first nucleoside phosphonates modified on their α-phosphates that act as efficient substrates for the human immunodeficiency virus type 1 (HIV-1) reverse transcriptase (RT). These analogues were synthesized and evaluated for their in vitro activity against wild-type (WT), K65R, and R72A RTs. BH3-PMEApp and BH3-PMPApp exhibit the same inhibition properties as their nonborane analogues on WT RT. However, K65R RT was found hypersensitive to BH3-PMEApp and as sensitive as WT RT to BH3-PMPApp. Moreover, the presence of the borane group restores incorporation of the analogue by R72A HIV RT, the latter being nearly inactive with regular nucleotides. The BH3-mediated suppression of HIV-1 RT resistance, formerly described with nucleoside 5′-(α-p-borano)-triphosphate analogues, is thus also conserved at the phosphonate level. The present results show that an α-phosphate modification is also possible and interesting for phosphonate analogues, a result that might find application in the search for a means to control HIV RT-mediated drug resistance.
Histatin-Derived Monomeric and Dimeric Synthetic Peptides Show Strong Bactericidal Activity towards Multidrug-Resistant
Staphylococcus aureus
In Vivo
Authors: Welling Mick M. , Brouwer Carlo P. J. M. , van ′t Hof Wim , Veerman Enno C. I. , Amerongen Arie V. Nieuw
Published: July 2007

Homodimerization of histatin-derived peptides generally led to improved bactericidal activity against
Staphylococcus aureus
in vitro. In vivo, monomers and dimers were equally active in killing bacteria in mice with a soft tissue infection. Altogether, these peptides are promising compounds for the development of novel therapeutics against infections with drug-resistant bacteria.
Haemophilus ducreyi
Is Resistant to Human Antimicrobial Peptides
Authors: Mount Kristy L. B. , Townsend Carisa A. , Bauer Margaret E.
Published: July 2007

We examined the susceptibility of
Haemophilus ducreyi
to antimicrobial peptides likely to be encountered in vivo during human infection.
H. ducreyi
was significantly more resistant than
Escherichia coli
to the bactericidal effects of all peptides tested. Class I and II
H. ducreyi
strains exhibited similar levels of resistance to antimicrobial peptides.
Azithromycin Blocks Quorum Sensing and Alginate Polymer Formation and Increases the Sensitivity to Serum and Stationary-Growth-Phase Killing ofPseudomonas aeruginosaand Attenuates ChronicP. aeruginosaLung Infection inCftr−/−Mice
Authors: Hoffmann Nadine , Lee Baoleri , Hentzer Morten , Rasmussen Thomas Bovbjerg , Song Zhijun , Johansen Helle Krogh , Givskov Michael , Høiby Niels
Published: July 2007

The consequences of O-acetylated alginate-producingPseudomonas aeruginosabiofilms in the lungs of chronically infected cystic fibrosis (CF) patients are tolerance to both antibiotic treatments and effects on the innate and the adaptive defense mechanisms. In clinical trials, azithromycin (AZM) has been shown to improve the lung function of CF patients. The present study was conducted in accordance with previous in vitro studies suggesting that the effect of AZM may be the inhibition of alginate production, blockage of quorum sensing (QS), and increased sensitivity to hydrogen peroxide and the complement system. Moreover, we show that AZM may affect the polymerization ofP. aeruginosaalginate by the incomplete precipitation of polymerized alginate and high levels of readily dialyzable uronic acids. In addition, we find that mucoid bacteria in the stationary growth phase became sensitive to AZM, whereas cells in the exponential phase did not. Interestingly, AZM-treatedP. aeruginosa lasImutants appeared to be particularly resistant to serum, whereas bacteria with a functional QS system did not. We show in a CF mouse model of chronicP. aeruginosalung infection that AZM treatment results in the suppression of QS-regulated virulence factors, significantly improves the clearance ofP. aeruginosaalginate biofilms, and reduces the severity of the lung pathology compared to that in control mice. We conclude that AZM attenuates the virulence ofP. aeruginosa, impairs its ability to form fully polymerized alginate biofilms, and increases its sensitivity to complement and stationary-phase killing, which may explain the clinical efficacy of AZM.
Enterococcal Leucine-Rich Repeat-Containing Protein Involved in Virulence and Host Inflammatory Response
Authors: Brinster Sophie , Posteraro Brunella , Bierne Hélène , Alberti Adriana , Makhzami Samira , Sanguinetti Maurizio , Serror Pascale
Published: July 2007

Enterococcus faecalis
is an important nosocomial pathogen associated with high morbidity and mortality for patients who are immunocompromised or who have severe underlying diseases. The
E. faecalis
genome encodes numerous surface-exposed proteins that may be involved in virulence. This work describes the characterization of the first internalin-like protein in
E. faecalis
, ElrA, belonging to the recently identified WxL family of surface proteins. ElrA contains an N-terminal signal peptide for export, a leucine-rich repeat domain that may interact with host cells, and a C-terminal WxL domain that interacts with the peptidoglycan. Disruption of the
elrA
gene significantly attenuates bacterial virulence in a mouse peritonitis model. The
elrA
deletion mutant also displays a defect in infection of host macrophages and a decreased interleukin-6 response in vivo. Finally,
elrA
expression is induced in vivo. Altogether, these results demonstrate a role for ElrA in the
E. faecalis
infectious process in vivo and suggest that this surface protein may contribute to
E. faecalis
virulence by stimulating the host inflammatory response.
Mast Cell-Mediated Changes in Smooth Muscle Contractility during Mouse Giardiasis
Authors: Li Erqiu , Zhao Aiping , Shea-Donohue Terez , Singer Steven M.
Published: July 2007

Giardia intestinalis
is a significant cause of diarrheal disease worldwide. Infections in animal models have been shown to cause changes in gastrointestinal transit that depend on adaptive immune responses and are mediated, in part, through neuronal nitric oxide synthase. Nitric oxide is an inhibitory neurotransmitter, and we therefore investigated potential excitatory pathways that might be involved in the response to
Giardia
infection. Infected mice exhibited increased spontaneous and cholecystokinin (CCK)-induced contractions of longitudinal smooth muscle. In contrast, enhanced contractile responses were not observed in response to acetylcholine, 5-hydroxytryptamine, or the protease-activated receptor-1 agonist peptide TFFLR.
Giardia
-induced changes in smooth muscle function appear to be mediated primarily by mast cells, as both spontaneous and CCK-induced contractions were blocked by pretreatment with either ketotifen or compound 48/80. Together, these data support a model in which CCK release triggers mast cell degranulation, leading to increases in smooth muscle contractility. These contractions, coupled with nitric oxide-mediated muscle relaxation, promote intestinal transit and parasite elimination.
Solid-Liquid Equilibrium in the System Propanoic Acid-Formamide
Authors: Sedláková Zuzana , Malijevská Ivona , Bureš Michal
Published: July 2007

Solid-liquid equilibria in the system propanoic acid-formamide were determined from time-temperature cooling and warming curves. In the system, two solid adducts, stable and metastable, were found and their equilibrium dissociation constants were calculated.
Cyclic Voltammetry of Iodine at the Organic Liquid/Aqueous Solution Interface
Authors: Xie Shaoai , Jia Jinping , Chen Hong-Jin
Published: July 2007

The electrochemical behavior of iodine extracted with an organic solvent at the liquid/liquid interface was studied using a new composite electrode. The effects of various solvents and supporting electrolyte on the electrochemical reaction of iodine were analyzed by cyclic voltammetric curves. The formation of a polar solvent complex of iodine and a strong donor solvent in organic solution was comfirmed by UV-VIS spectra. A possible mechanism was suggested based on experiments. This method makes it possible to measure heavy metal ion in solution indirectly.
The health benefits of interactive video game exercise
Authors: Warburton Darren E.R. , Bredin Shannon S.D. , Horita Leslie T.L. , Zbogar Dominik , Scott Jessica M. , Esch Ben T.A. , Rhodes Ryan E.
Published: July 2007

The purpose of this study was to evaluate the effectiveness of interactive video games (combined with stationary cycling) on health-related physical fitness and exercise adherence in comparison with traditional aerobic training (stationary cycling alone). College-aged males were stratified (aerobic fitness and body mass) and then assigned randomly to experimental (n = 7) or control (n = 7) conditions. Program attendance, health-related physical fitness (including maximal aerobic power (VO2 max), body composition, muscular strength, muscular power, and flexibility), and resting blood pressure were measured before and after training (60%–75% heart rate reserve, 3 d/week for 30 min/d for 6 weeks). There was a significant difference in the attendance of the interactive video game and traditional training groups (78% ± 18% vs. 48% ± 29%, respectively). VO2 max was significantly increased after interactive video game (11% ± 5%) but not traditional (3% ± 6%) training. There was a significantly greater reduction in resting systolic blood pressure after interactive video game (132 ± 6 vs. 123 ± 6 mmHg) than traditional (131 ± 7 vs. 128 ± 8 mmHg) training. There were no significant changes in body composition after either training program. Attendance mediated the relationships between condition and changes in health outcomes (including VO2 max, vertical jump, and systolic blood pressure). The present investigation indicates that a training program that links interactive video games to cycle exercise results in greater improvements in health-related physical fitness than that seen after traditional cycle exercise training. It appears that greater attendance, and thus a higher volume of physical activity, is the mechanism for the differences in health-related physical fitness.
Exertional fatigue and cold exposure: mechanisms of hiker's hypothermia
Authors: Young Andrew J. , Castellani John W.
Published: July 2007

Participants in prolonged, physically demanding activities in cold weather are at risk of a condition known as “hiker's hypothermia”. During exposure to cold weather, the increased gradient favoring body heat loss to the environment must be balanced by physiological responses, clothing, and behavioral strategies that conserve body heat stores, or else body temperature will decline. The primary human physiological responses elicited by cold exposure are shivering and peripheral vasoconstriction. Shivering increases thermogenesis and replaces body heat losses, while peripheral vasoconstriction improves thermal insulation of the body and retards the rate of heat loss. A body of scientific literature supports the concept that prolonged and (or) repeated cold exposure, fatigue induced by sustained physical exertion, or both together can impair shivering and vasoconstrictor response to cold. The mechanisms accounting for this thermoregulatory impairment are not clear, but the possibility that changes in blood glucose availability or sympathetic responsiveness to cold due to exertion and fatigue merit further research.
Time-of-day variation in cardiovascular response to maximal exercise testing in coronary heart disease patients taking a beta-blocker
Authors: Dufour Doiron Monique , Prud’homme Denis , Boulay Pierre
Published: July 2007

The aim of this study was to investigate the effect of a beta-blocker (atenolol and metoprolol) on exercise heart rate (HR) and rate pressure product (RPP) during a morning and afternoon maximal exercise test (maxET) in patients with coronary heart disease (CHD). Twenty-one CHD patients (59.9 ± 8.9 years of age) treated with either atenolol or metoprolol participated in this study. All subjects underwent a morning and afternoon symptom-limited maximal exercise test (maxET) 2–3 h and 8–10 h after medication intake. No significant differences in exercise capacity (atenolol: 8.3 ± 1.9 vs. 8.3 ± 2.1 metabolic equivalents (METs); metoprolol: 8.8 ± 2.0 vs. 8.7 ± 2.0 METs) or rate of perceived exertion (atenolol: 7.4 ± 1.9 vs. 7.4 ± 1.7 METs; metoprolol: 7.2 ± 1.5 vs. 6.8 ± 0.9 METs) were observed between the 2 maxETs in either group. However, there was a discrepancy in cardiovascular and ischemic responses between morning and afternoon maxET. Subjects treated with atenolol demonstrated better overall control of HR and RPP during the afternoon maxET. The difference between morning and afternoon HRmax (11 ± 8 vs. 19 ± 9 beats·min–1; p = 0.05) was significantly higher in the metoprolol group, but did not attain significance for RPP (31 ± 30 vs. 54 ± 28 mmHg·beats·min–1·10−2; p = 0.09). Also, nearly one quarter of our subjects who had a normal morning maxET demonstrated an abnormal electrocardiogram response and (or) ischemia when exercise testing was done in the late afternoon. These changes were more prevalent in subjects taking metoprolol. The results of this study suggest that there is considerable time-of-day variation in the cardiovascular response to a maxET in CHD patients treated with a beta-blocker.