bluuebunny/crossref_metadata_2025 huggingface dataset:
Influence of adult nutrition on the relationship between body size and reproductive parameters in a parasitoid wasp
Authors: Bezemer T. Martijn , Harvey Jeffrey A. , Mills Nick J.
Published: September 2005

Abstract.  1. An important constraint upon life‐history evolution in parasitoids is the limit imposed by body size on allocation of limited metabolic resources to different fitness‐related physiological functions such as reproduction and survival.

2. The influence of adult nutrition on reproductive and maintenance variables was studied in the synovigenic ectoparasitoid Mastrus ridibundus, and it was determined whether resource allocation to these different functions depends on body size.

3. Over the course of adult life there was a positive relationship between body size and the number of mature eggs in adult females both in the presence and absence of food. However, only in the presence of food did egg maturation rates increase significantly with body size. Starved wasps produced significantly smaller eggs than fed ones, which has not been documented before. Moreover, starved wasps produced fewer offspring than fed wasps, and attacked fewer hosts.

4. The availability of food had a major effect on longevity, with fed females living about 10 times longer than starved ones. There was also a positive relationship between body size and longevity. In starved wasps, this relationship was the same both in the presence and absence of hosts, but in fed wasps there was a positive relationship between body size and longevity in the absence of hosts only. Allocation to initial eggs relative to lifetime progeny production did not decline with body size.

5. The data reveal that in M. ridibundus the trade‐off between maintenance and reproduction varies with life expectancy.
Contingencies of Self-Worth
Authors: Crocker Jennifer , Knight Katherine M.
Published: September 2005

We argue that the importance of self-esteem lies in what people believe they need to be or do to have worth as a person. These contingencies of self-worth are both sources of motivation and areas of psychological vulnerability. In domains of contingent self-worth, people pursue self-esteem by attempting to validate their abilities and qualities. This pursuit of self-esteem, we argue, has costs to learning, relationships, autonomy, self-regulation, and mental and physical health. We suggest alternatives to this costly pursuit of self-esteem.
Expression of matrix metalloproteinases and tissue inhibitors of metalloproteinases during normal human pulmonary development
Authors: Masumoto K , De Rooij J D , Suita S , Rottier R , Tibboel D , De Krijger R R
Published: September 2005

Aims : Matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs) are thought to be involved in lung development because they play an important role in the turnover of the extracellular matrix. Although limited data on MMP and TIMP expression are available from animal studies during prenatal pulmonary development, little is known about their expression during human fetal lung development. The aim of this study was to investigate the expression of MMP‐1, ‐2, ‐9, TIMP‐1, ‐2 and ‐3 in human fetal lungs from 9 to 42 weeks of gestation.

Methods and results : Forty‐five normal human fetal lung samples were analysed by immunohistochemistry. MMP‐1, ‐9, TIMP‐1, ‐2 and ‐3, but not MMP‐2, were expressed in the epithelium at all gestational ages. The endothelium of all vessels and the arterial smooth muscle cells expressed MMP‐1, ‐2, ‐9, TIMP‐2 and ‐3, but not TIMP‐1, at all developmental stages.

Conclusion : The extensive distribution of MMPs and TIMPs throughout all stages of human lung development suggests that they play a significant role in the remodelling that occurs in the interstitium and epithelial basement membrane during lung development and in pulmonary vascular development. These data will serve as a base line for comparison with neonatal lung pathology, including pulmonary hypertension.
Cold hardening and transcriptional change in Drosophila melanogaster
Authors: Qin W. , Neal S. J. , Robertson R. M. , Westwood J. T. , Walker V. K.
Published: September 2005

Cold hardening treatment – a brief exposure to low temperatures – can protect certain insects against subsequent exposure to temperatures sufficiently low to cause damage or lethality. Microarray analysis to examine the changes in transcript abundance associated with cold hardening treatment (0 °C for 2 h followed by 30 min recovery at 25 °C) was undertaken in Drosophila melanogaster in order to gain insight into this phenomenon. Transcripts associated with 36 genes were identified, a subset of which appeared to be also differentially expressed after heat shock treatment. Quantitative RT‐PCR was used to independently determine transcript abundance of a subset of these sequences. Taken together, these assays suggest that stress proteins, including Hsp23, Hsp26, Hsp83 and Frost as well as membrane‐associated proteins may contribute to the cold hardening response.
Regulation of methane oxidation in the facultative methanotroph Methylocella silvestris BL2
Authors: Theisen Andreas R. , Ali M. Hanif , Radajewski Stefan , Dumont Marc G. , Dunfield Peter F. , McDonald Ian R. , Dedysh Svetlana N. , Miguez Carlos B. , Murrell J. Colin
Published: September 2005

The molecular regulation of methane oxidation in the first fully authenticated facultative methanotroph Methylocella silvestris BL2 was assessed during growth on methane and acetate. Problems of poor growth of Methylocella spp. in small‐scale batch culture were overcome by growth in fermentor culture. The genes encoding soluble methane monooxygenase were cloned and sequenced, which revealed that the structural genes for soluble methane monooxygenase, mmoXYBZDC, were adjacent to two genes, mmoR and mmoG, encoding a σ54 transcriptional activator and a putative GroEL‐like chaperone, located downstream (3′) of mmoC. Transcriptional analysis revealed that the genes were all cotranscribed from a σ54‐dependent promoter located upstream (5′) of mmo X. The transcriptional start site was mapped. Transcriptional analysis of soluble methane monooxygenase genes and expression studies on fermentor grown cultures showed that acetate repressed transcription of sMMO in M. silvestris BL2. The possibility of the presence of a particulate, membrane‐bound methane monooxygenase enzyme in M. silvestris BL2 and the copper‐mediated regulation of soluble methane monooxygenase was investigated. Both were shown to be absent. A promoter probe vector was constructed and used to assay transcription of the promoter of the soluble methane monoxygenase genes of M. silvestris BL2 grown under various conditions and with different substrates. These data represent the first insights into the molecular physiology of a facultative methanotroph.
A deficiency in S‐adenosylmethionine synthetase interrupts assembly of the septal ring in Escherichia coli K‐12
Authors: Wang Shan , Arends S. J. Ryan , Weiss David S. , Newman Elaine B.
Published: September 2005

A mutant in which S‐adenosylmethionine synthetase is underexpressed makes filaments with no visible septa. Examination with GFP fusions to various septal proteins shows that FtsZ, ZipA and FtsA localize to the septal ring, but FtsQ, FtsW, FtsI or FtsN do not. The requirement for S‐adenosylmethionine suggests that some methylation reaction is required before a complete septal ring can be assembled.
Bronchial hyper‐responsiveness predicts the development of mild clinical asthma within 2 yr in school children with hay‐fever
Authors: Ferdousi Hosne Ara , Zetterström Olle , Dreborg Sten
Published: September 2005

In children with mild asthma, symptoms are not always apparent. Therefore, results of tests play an important role for the diagnosis. First, to investigate whether children with bronchial hyper‐responsiveness (BHR) but no symptoms of asthma in 1992 had developed clinical asthma at follow up in 1994. The second aim was to find out the diagnostic properties of tests for asthma/allergic inflammation, using either doctor diagnosed asthma (DDA), self‐assessed symptoms of asthma or iso‐capnic hyperventilation of cold air (IHCA), as the standard, to diagnose asthma in a group of children with hay fever. Twenty‐eight children with pollinosis, 12 of them with a history of asthma for the first time during the season 1992, were studied during the birch pollen season and in the autumn of 1994. During both periods, the bronchial hyper‐reactivity was estimated by methacholine bronchial provocation tests (MBPT), bronchial variability by peak expiratory flow rate variability, subjective symptoms of asthma by visual analogue scale (VAS) and bronchial inflammation by serum and urine levels of inflammatory mediators. In 1994 IHCA was added during both seasons. Eight of 16 children with BHR but without clinical asthma in 1992 had developed asthma in 1994, 14 of 16 reacted to IHCA and 13 to MBPT. All 12 children with DDA in 1992 had still asthma in 1994 and 14 children with BHR in 1992 had persistent BHR in 1994. Of 23 children with BHR in 1992, 17 had DDA in 1994 and all maintained their BHR. Furthermore, 20 of them reacted to IHCA in 1994. In 1994, 24 of 28 hay‐fever children had a positive IHCA tests and 24 had positive MBPT. In relation to VAS, the sensitivity of IHCA and MBPT to predict present asthma was high, but the specificity low, whereas the specificity of most other tests was high, but based on few individuals. In relation to DDA both the IHCA test (65–80%) and the MBPT test (79–85%) had a high sensitivity and it was three to six times more likely to find a positive test among asthmatics than in non‐asthmatics. Children with hay fever without clinical asthma have a high risk of developing asthma within 2 yr. In relation to DDA, inhalation of cold air and the MBPT showed a high sensitivity.
Maternal experiences of peanut avoidance during pregnancy/lactation: An in‐depth qualitative study
Authors: Turke Joanna , Venter Carina , Dean Taraneh
Published: September 2005

In 1998 the Department of Health Committee on Toxicity of Chemicals in Food, Consumer Products and the Environment issued a report to British general practitioners, which advised that pregnant mothers with a family history of atopy may wish to avoid peanuts during pregnancy/lactation. To explore the lived‐in experience of mothers who avoided/did not avoid peanuts during pregnancy/lactation in the light of the information issued. A qualitative approach, using unstructured in‐depth interviews to explore what it was like for mothers to have a particular experience. A purposive sample frame was designed to ensure a maximum variation of participants. Forty‐two interviews were conducted: 25 participants avoided peanuts; 15 with a family history of atopy and 10 with no such history. Seventeen participants did not avoid peanuts; 10 with a family history of atopy and seven with no such history. Emergent themes included: variations in information provision, a lack of clarity in relation to information and advice about peanut avoidance, the risks entailed and the introduction of peanuts to the developing child's diet; the importance of atopy in influencing participants’ decisions to avoid peanuts and the importance of individual's choice in the decision making process. There was a significant difference in family size with respect to avoidance behaviour with ‘avoider’ families being smaller (p = 0.007). Avoidance was more likely in single child families (71% vs. 53%) although this difference was not significant. Improvements to the experience of avoidance and/or non‐avoidance were primarily focused around provision of information and advice. In particular, a need for clear, consistent factual information and advice about the real risks associated with peanut consumption during pregnancy/lactation, and to whom these risks apply.
Association study of Glutathione S‐transferase P1 (GSTP1) with asthma and bronchial hyper‐responsiveness in two German pediatric populations
Authors: Nickel Renate , Haider Assja , Sengler Claudia , Lau Susanne , Niggemann Bodo , Deichmann Klaus A. , Wahn Ulrich , Heinzmann Andrea ,   MAS‐Study Group
Published: September 2005

Glutathione S‐Transferase P1 (GSTP1) is an important enzyme in the detoxification of products of oxidative stress. Several studies have shown an association of the amino acid variant Ile105Val with bronchial asthma and the reaction of the lung to inhalant pollutants. The aim of this study was to test the two known amino acid variants in GSTP1 for association with bronchial asthma and airway hyper‐responsiveness in two German pediatric populations. We genotyped Ile105Val and Ala114Val in the Multicenter Allergy Study cohort (85 children with asthma, 123 controls) and asthmatic children from Freiburg (n = 178). We did not find association of either polymorphisms with bronchial asthma or airway hyper‐responsiveness. We conclude from our data that polymorphisms within GSTP1 do not play a major role in the development of bronchial asthma in German children.
A different pattern of risk factors for atopic and non‐atopic wheezing in 9–12‐year‐old children
Authors: García‐Marcos Luis , Castro‐Rodríguez Jose A. , Suarez‐Varela María Morales , Garrido Jose Batlles , Hernandez Gloria García , Gimeno Antonio Martínez , González Agustín Llopis , Ruiz Teresa Rubí , Torres Antonela Martínez
Published: September 2005

Few epidemiological studies have compared the risk factors of asthma or wheezing between atopic and non‐atopic children. The objective of this study was to determine if there are specific risk factors for current wheezing related to atopic status in schoolchildren. Schoolchildren 9–12 yr of age from three Spanish cities (n = 2720) were subject to a cross‐sectional study of asthma risk factors (by questionnaire) and atopy (by skin prick test) according to the ISAAC phase‐II protocol. Risk factors for current wheezing (in the last 12 months) as reported by parents were investigated among the atopic (positive prick test to at least one allergen) and the non‐atopic (negative prick test) children. The prevalence of current wheezing was 13.1% in the whole group, 22.1% in the atopic group and 7.8% in the non‐atopic group. However, only 62.4% of children with current wheezing were atopic. Male gender and asthma in the mother and/or the father were both significant and independent risk factors for current atopic wheezing, whereas maternal smoking in the first year of the child's life and mould stains on the household walls were for current non‐atopic wheezing. In summary, this study shows that atopic and current non‐atopic wheezing children in Spain do not share identical environmental and family risk factors.
Neurophysiologic changes in live related kidney transplant children and adolescents
Authors: El‐Husseini Amr A. , Abu‐Hegazy Mohammad , El‐Tantawi Abd El‐Halim , Sobh Mohamed A. , Ghoneim Mohamed A.
Published: September 2005

Abstract:  Uremic neuropathy is one of the most debilitating symptoms associated with end stage renal disease. In adults the only potential cure for uremic neuropathy is renal transplantation. No studies have investigated the neurophysiologic abnormalities among pediatric renal transplant recipients. The objective of this study is to describe the incidence, nature and factors affecting neurophysiologic abnormalities in young renal transplant recipients. Neurophysiologic study was performed for 31 of our live related pediatric renal transplant recipients; they were 21 males and 10 females. The mean age at transplantation was 13.2 ± 3.1 yr. The neurophysiologic studies were performed at different time points after transplantation (range 12–60 months), with a mean period of follow‐up after transplantation 3.2 ± 1.1 yr. Electromyography of the following muscles was tested: abductor pollicis brevis of the thenar eminence, biceps brachii, extensor digitorum brevis and rectus femoris. The median and lateral popliteal nerves were tested for estimating the motor conduction velocity. Neuropathic changes were found in 19% of our cases with more affection of the distal muscles of lower limbs. Motor conduction velocities were reduced, distal latencies were lengthened, and motor unit action potentials were reduced or dispersed. The predictors for development of neuropathy by multivariate analysis were the cumulative steroid dose and graft dysfunction. These results suggest that neuropathy is prevalent among young pediatric renal transplants. The independent predictors for development of neuropathy are graft dysfunction and anemia. It is unclear how significant these findings are in view of absent clinical signs and symptoms. This may represent an early stage of a disease that is still silent.
Successful liver transplantation for giant cell hepatitis and Coombs‐positive hemolytic anemia: A case report
Authors: Akyildiz Murat , Karasu Zeki , Arikan Cigdem , Nart Deniz , Kilic Murat
Published: September 2005

Abstract:  Giant cell hepatitis (GCH) with autoimmune hemolytic anemia (AHA) is a distinct entity with an aggressive course. Drugs, autoimmunity, and viruses have been implicated in its etiology. Without treatment, liver dysfunction is progressive and fatal. Although succesful immunosuppressive treatment has been reported, a few patients have undergone liver transplantation with recurrence of the primary disease in the allograft. We report, an 18‐year‐old boy with progressive GCH with AHA without recurrence in the allograft following deceased donor (DD) liver transplantation.
Risk for post‐transplant lymphoproliferative disorder after polyclonal antibody induction in kidney transplantation
Authors: Dharnidharka Vikas R. , Stevens Gary
Published: September 2005

Abstract:  The adjusted relative risk (aRR) for development of post‐transplant lymphoproliferative disorder (PTLD) is higher in kidney transplant recipients receiving monoclonal antibody induction therapy, but the aRR between the different available polyclonal agents has not been investigated in detail. We analyzed data from the United Network of Organ Sharing registry on all kidney transplants performed between 1987 and 2003. The aRR for PTLD development was calculated using SAS 9.0 statistical software and Cox proportional hazards modeling, adjusting for multiple covariates. There were 539 cases of PTLD among 84 907 kidney transplant recipients, who received either polyclonal antibody induction or no induction therapy. In adjusted analysis, the aRR for PTLD development (vs. no induction) was significantly higher with use of equine anti‐thymocytic globulin (E‐ATG; aRR = 1.61, p = 0.0003) or anti‐lymphocytic globulin (ALG; aRR = 1.35, p = 0.0055) but not with rabbit anti‐thymocytic globulin (R‐ATG; aRR = 1.17, p = 0.29, NS). Median follow up times were significantly shorter in the R‐ATG cohort than the ALG or E‐ATG cohort (median 368 vs. 1433 and 2055 day). However, in an analysis restricted to pediatric recipients, where median times to PTLD are less than 200 days, only E‐ATG was associated with a higher aRR for PTLD (aRR = 2.16, p = 0.0078), while R‐ATG and ALG were not. There is a higher aRR for PTLD after kidney transplantation with E‐ATG, but not R‐ATG. This may only partially be explained by shorter follow up time and may represent differential hazard for PTLD among the agents.
Anesthetic issues in pediatric liver transplantation
Authors: Yudkowitz Francine S. , Chietero Michael
Published: September 2005

Abstract:  Pediatric liver transplantations are becoming increasingly more common. Recent advances in the surgical and anesthetic management of these cases have greatly improved the survival rate. In order to successfully manage the anesthesia in these patients, one needs to have a thorough understanding of the pathophysiology of end‐stage liver disease and the subsequent anesthetic implications. It is also necessary to appreciate the stages of the surgical procedure, as each stage presents different dilemmas to the anesthesiologist. This article will review the pathophysiology of liver failure in pediatric patients and outline the particular issues related to each stage of liver transplantation, allowing for the anticipation and management of the derangements that occur during surgery.
Hepatitis C: Current approaches in pediatrics
Authors: Rumbo Carolina
Published: September 2005

Abstract: Chronic hepatitis C virus is one of the leading causes of liver diseases in adults and it is the most common cause of liver transplantation in the USA. Hepatitis C infection in children is less frequent; there is less information about its clinical course. Compared with adults, there are differences in its mode of acquisition, natural history, complications and even available treatments. The aim of this paper is to give an overview of chronic hepatitis C in children.
Orbital cellulitis and intraocular abscess caused by migrating grass in a cat
Authors: Tovar Mari Carmen , Huguet Eduardo , Gomezi Miguel Angel
Published: September 2005

We report an unusual case of orbital cellulitis in a cat. Drainage via the pterygopalatine fossa and medical treatment were performed. Failure of resolution and loss of ocular structure and visual function with a poor prognosis led to enucleation. During surgery, plant material and purulent exudate were present in the orbit. Histopathology showed an intraocular foreign body of grass that had migrated through the sclera causing a suprachoroidal abscess with choroidal and retinal detachment.
Vascular changes associated with chorioretinal and optic nerve colobomas in rats (Crj: CD(SD), IGS)
Authors: Ninomiya Hiroyoshi , Kuno Hiroshi , Inagaki Satoru
Published: September 2005

Objective  Three female adult rats (Crj: CD(SD) IGS) with colobomatous anomalies were investigated.

Materials and methods  The microvascular changes of the coloboma were studied using the techniques of fluorescein angiography, histology and scanning electron microscopy (SEM) of vascular corrosion casts.

Results  Fluorescein angiography revealed the pits of the optic disk as a dark hole with some abnormalities in vessel arrangement. Light microscopy confirmed the presence of attenuated lamina cribrosa, retinal dysplasia and marked dilation of the retinal veins. SEM revealed that the optic disk coloboma formed a crater‐like pit and that central retinal vessels ran a tortuous course along the bottom and side of the crater. Capillaries in the optic nerve head were missing in the affected area. The central retinal veins were thick and had various changes such as strangulation, rough surface structures, mural voids and evaginations, which represent loss of integrity of the vascular wall.

Conclusions  These vascular changes that are associated with colobomatous anomalies may impede the retinal circulation and be responsible for the fluctuating fluorescein pattern during fluorangiogram of affected animals. The lesions of the vascular wall may increase the subretinal fluid due to the leakage of fluid, thus causing the maculopathy or serous retinopathy, which is frequently associated with posterior pole coloboma.
Effects of endotoxin and allergen alone and in combination on the sensitivity of the rat airways to adenosine
Authors: Karmouty Quintana H. , Mazzoni L. , Fozard J. R.
Published: September 2005

1 The airways of patients with asthma are hyperresponsive to adenosine. The phenomenon can be mimicked in the actively sensitized Brown Norway rat by exposure to allergen or lipopolysaccharide (LPS). We wondered whether combined treatment with allergen and endotoxin would result in additive effects or synergism with respect to increasing the sensitivity of the airways of the Brown Norway rat to adenosine.

2 Animals actively sensitized to ovalbumin and challenged intratracheally with allergen or endotoxin manifested increased bronchoconstrictor responses to adenosine. A combination of ovalbumin and endotoxin also increased the response to adenosine but the effects were at best additive.

3 Changes in the response to adenosine were selective as responses to 5‐hydroxytryptamine were unaltered following ovalbumin or LPS either alone or in combination.

4 Thus, endotoxin and allergen acting together could play a role in up‐regulating the response of the human asthmatic airway to adenosine. However, our data suggest that the interaction would be additive rather than synergistic.
WAY 405, a new silent 5‐HT1A receptor antagonist with low affinity for vascular α1‐adrenoceptors
Authors: Villalobos‐Molina R. , Orozco‐Méndez M. , López‐Guerrero J. J. , Gallardo‐Ortíz I. A.
Published: September 2005

1 The effect of WAY 405 ((R)‐N‐(2‐methyl‐(4‐indolyl‐1‐piperazinyl)ethyl)‐N‐(2‐pyridinyl) cyclohexane carboxamide), a putative 5‐HT1A receptor antagonist, on cardiovascular function was studied.

2 In anaesthetized rats, the i.v. injection of WAY 405 did not significantly modify basal heart rate nor blood pressure at doses of 1, 3, 10 and 30 μg kg−1; while the antagonist dose dependently antagonized the 5‐HT1A receptor agonist, 8‐OH‐DPAT (8‐hydroxy‐2‐(di‐n‐propylamino)tetralin)‐induced hypotension and bradycardia.

3 WAY 405 antagonized noradrenaline‐induced contraction in isolated arteries, with pKB values of 6.6 ± 0.1, 6.5 ± 0.1 and 6.5 ± 0.1, for rat tail artery (α1A‐adrenoceptors), rabbit aorta (α1B‐adrenoceptors), and rat aorta (α1D‐adrenoceptors) respectively.

4 The results show that in the control of blood pressure the new compound, WAY 405, behaves as a silent 5‐HT1A receptor antagonist in the anaesthetized rat, also having low affinity for vascular α1‐adrenoceptors.
United States Public Response to Terrorism: Fault Lines or Bedrock?1
Authors: Jenkins‐Smith Hank C. , Herron Kerry G.
Published: September 2005

We test traditional assumptions about the volatility of mass opinion in times of national crises using data about views of terrorism from national surveys of the United States general public in 1995 and 1997, findings from a national survey immediately following the terrorist attacks of September 11, 2001 (9/11), and panel data from a follow‐up survey in 2002. We compare public assessments of the threat of terrorism, willingness to restrict speech to prevent terrorism, support for employing conventional military force against countries that support terrorism, and levels of certainty about culpability required prior to using military force. Results show stable and measured public views prior to 9/11, immediately following the events of that date, and in the subsequent year. Our findings support democratic and modernist theories of public capacities while challenging long‐standing traditional precepts about widespread volatility of mass public opinion.
Properties of Tm3+‐Doped Germanotellurite Glasses for S‐Band Amplifier
Authors: Kishi Yuki , Tanabe Setsuhisa
Published: September 2005

Optical and material properties of (75−x)TeO2–xGeO2–20ZnO–5Na2O–0.1Tm2O3 glasses were investigated as candidate materials for an S‐band Tm‐doped fiber amplifier (TDFA). With increasing GeO2 content, the lifetime and the quantum efficiency of the 1.46 μm emission decreased slightly, while the emission bandwidth, the Vickers hardness, and thermal stability of the glass improved monotonically. Above 20 mol% GeO2, the quantum efficiency decreased more rapidly with increasing GeO2. We conclude that addition of a small amount of germania may improve material properties without deteriorating the optical properties of doped Tm3+, and thus the germanotellurite fiber may be a more reliable material for the S‐band TDFA in wavelength‐division‐multiplexing telecommunication.
Dielectric Loss Spectrum of Ceramic MgTiO3 Investigated by AC Impedance and Microwave Resonator Measurements
Authors: Kuang Xiaojun , Jing Xiping , Tang Zongxi
Published: September 2005

MgTiO3 ceramic was selected as a model material of the microwave dielectric ceramics for the investigation of the dielectric loss spectrum. Conductivity spectra in the low‐frequency range 1–106 Hz at elevated temperatures and the dielectric loss spectrum in the microwave range 6–14 GHz at room temperature were characterized by AC impedance spectroscopy and the microwave resonator method, respectively. The experimental data were analyzed by using Jonscher's universal power law, the Arrhenius equation as well as the classic dispersion theory. Consequently, a dielectric loss spectrum (tg δ∼f plot) at room temperature in a wide frequency range was obtained. Based on the loss spectrum, the dielectric loss can be classified into three mechanisms in MgTiO3 ceramic (each dominates the loss in different frequency ranges): DC conductance (in DC field), AC conductance (<107 Hz), and anharmonicity of lattice vibration (in GHz range). The influence of defects on the microwave dielectric loss possibly is because of atom defects via damage of the perfection of lattice and modification of the anharmonic force in lattice, while the electronic defects trapped on the atomic defects affect the DC and AC losses.
Macrophage Internalization of Fungal β-Glucans Is Not Necessary for Initiation of Related Inflammatory Responses
Authors: McCann Frances , Carmona Eva , Puri Vishwajeet , Pagano Richard E. , Limper Andrew H.
Published: September 2005

Cell wall β-glucans are highly conserved structural components of fungi that potently trigger inflammatory responses in an infected host. Identification of molecular mechanisms responsible for internalization and signaling of fungal β-glucans should enhance our understanding of innate immune responses to fungi. In this study, we demonstrated that internalization of fungal β-glucan particles requires actin polymerization but not participation of components of caveolar uptake mechanisms. Using fluorescence microscopy, we observed that uptake of 5-([4,6-dichlorotriazin-2-yl] amino)-fluorescein hydrochloride-Celite complex-labeledSaccharomyces cerevisiaeβ-glucan by RAW macrophages was substantially reduced in the presence of cytochalasin D, which antagonizes actin-mediated internalization pathways, but not by treatment with nystatin, which blocks caveolar uptake. Interestingly, β-glucan-induced NF-κB translocation, which is necessary for inflammatory activation, and tumor necrosis factor alpha production were both normal in the presence of cytochalasin D, despite defective internalization of β-glucan particles following actin disruption. Dectin-1, a major β-glucan receptor on macrophages, colocalized to phagocytic cups on macrophages and exhibited tyrosine phosphorylation after challenge with β-glucan particles. Dectin-1 localization and other membrane markers were not affected by treatment with cytochalasin D. Furthermore, dectin-1 receptors rather than Toll-like receptor 2 receptors were shown to be necessary for both efficient internalization of β-glucan particles and cytokine release in response to the fungal cell wall component.
Adherence to Human Vaginal Epithelial Cells Signals for Increased Expression of
Trichomonas vaginalis
Genes
Authors: Kucknoor Ashwini S. , Mundodi Vasanthakrishna , Alderete J. F.
Published: September 2005

Host parasitism by
Trichomonas vaginalis
is complex, and the adhesion to vaginal epithelial cells (VECs) by trichomonads is preparatory to colonization of the vagina. Since we showed increased synthesis of adhesins after contact with VECs (A. F. Garcia, et al., Mol. Microbiol.
47:
1207-1224, 2003) and more recently demonstrated up-regulated gene expression in VECs after parasite attachment (A. S. Kucknoor, et al., Cell. Microbiol.
7:
887-897, 2005), we hypothesized that enhanced expression of adhesin and other genes would result from signaling of trichomonads following adherence. In order to identify the genes that are up-regulated, we constructed a subtraction cDNA library enriched for differentially expressed genes from the parasites that were in contact with the host cells. Thirty randomly selected cDNA clones representing the differentially regulated genes upon initial contact of parasites with host cells were sequenced. Several genes encoded functional proteins with specific functions known to be associated with colonization, such as adherence, change in morphology, and gene transcription and translation. Interestingly, genes unique to trichomonads with unknown functions were also up-regulated. Semiquantitative reverse transcription-PCR (RT-PCR) confirmed expression of select genes. An increased amount of protein was demonstrated by immunoblotting with monoclonal antibody. Finally, we showed the transcriptional regulation of some genes by iron by using RT-PCR. To our knowledge, this is the first report addressing the differential regulation of
T. vaginalis
genes immediately upon contact with VECs.
Improved Resistance to Bacterial Superinfection in Mice by Treatment with Macrophage Migration Inhibitory Factor
Authors: Pollak N. , Sterns T. , Echtenacher B. , Männel D. N.
Published: September 2005

Nosocomial infections in immune-suppressed patients are a widespread problem in intensive care medicine. Such patients are highly susceptible to infections because their immune defenses are impaired and, therefore, unable to adequately combat invading microorganisms. To investigate the problem of sepsis-induced immune suppression, we used a model in which mice developed sublethal peritonitis induced by cecal ligation and puncture (CLP). Two days after CLP mice were in an immune-suppressed state, as measured by impaired capacity to produce tumor necrosis factor (TNF) and enhanced susceptibility to bacterial infections. Since macrophage migration inhibitory factor (MIF) is a critical mediator of septic shock by modulation of innate immune responses, the role of MIF in sepsis-induced immune suppression was analyzed. Neutralization of endogenous MIF further enhanced susceptibility to bacterial superinfection after CLP. Conversely, treatment with recombinant human MIF before the bacterial superinfection protected the animals. MIF treatment reconstituted the impaired capacity to produce proinflammatory cytokines, such as TNF and interleukin-6. This study indicates that MIF might be able to ameliorate the sepsis-induced immune suppression by reenabling the organism to react adequately to a secondary bacterial challenge.
Functions of Cell Surface-Anchored Antigen I/II Family and Hsa Polypeptides in Interactions of
Streptococcus gordonii
with Host Receptors
Authors: Jakubovics Nicholas S. , Kerrigan Steven W. , Nobbs Angela H. , Strömberg Nicklas , van Dolleweerd Craig J. , Cox Dermot M. , Kelly Charles G. , Jenkinson Howard F.
Published: September 2005

Streptococcus gordonii
colonizes multiple sites within the human oral cavity. This colonization depends upon the initial interactions of streptococcal adhesins with host receptors. The adhesins that bind salivary agglutinin glycoprotein (gp340) and human cell surface receptors include the antigen I/II (AgI/II) family polypeptides SspA and SspB and a sialic acid-binding surface protein designated Hsa or GspB. In this study we determined the relative functions of the AgI/II polypeptides and Hsa in interactions of
S. gordonii
DL1 (Challis) with host receptors. For an isogenic mutant with the
sspA
and
sspB
genes deleted the levels of adhesion to surface-immobilized gp340 were reduced 40%, while deletion of the
hsa
gene alone resulted in >80% inhibition of bacterial cell adhesion to gp340. Adhesion of
S. gordonii
DL1 cells to gp340 was sialidase sensitive, verifying that Hsa has a major role in mediating sialic acid-specific adhesion to gp340. Conversely, aggregation of
S. gordonii
cells by fluid-phase gp340 was not affected by deletion of
hsa
but was eliminated by deletion of the
sspA
and
sspB
genes. Deletion of the AgI/II polypeptide genes had no measurable effect on
hsa
mRNA levels or Hsa surface protein expression, and deletion of
hsa
did not affect AgI/II polypeptide expression. Further analysis of mutant phenotypes showed that the Hsa and AgI/II proteins mediated adhesion of
S. gordonii
DL1 to human HEp-2 epithelial cells. Hsa was also a principal streptococcal cell surface component promoting adhesion of human platelets to immobilized streptococci, but Hsa and AgI/II polypeptides acted in concert in mediating streptococcal cell-platelet aggregation. The results suggest that Hsa directs primary adhesion events for
S. gordonii
DL1 (Challis) with immobilized gp340, epithelial cells, and platelets. AgI/II polypeptides direct gp340-mediated aggregation, facilitate multimodal interactions necessary for platelet aggregation, and modulate
S. gordonii
-host engagements into biologically productive phenomena.
Analysis of Immune Responses Directed toward a Recombinant Early Secretory Antigenic Target Six-Kilodalton Protein-Culture Filtrate Protein 10 Fusion Protein inMycobacterium bovis-Infected Cattle
Authors: Maue Alexander C. , Waters W. Ray , Davis William C. , Palmer Mitchell V. , Minion F. Chris , Estes D. Mark
Published: September 2005

Cell-mediated immune responses are critical for protective immunity to mycobacterial infections. Recent progress in defining mycobacterial antigens has determined that region of difference 1 (RD1) gene products induce strong T-cell responses, particularly the early secretory antigenic target 6-kDa (ESAT-6) protein and culture filtrate protein 10 (CFP10). However, comprehensive analysis of the immune response towards these antigens is incompletely characterized. To evaluate recall responses to ESAT-6 and CFP10, peripheral blood mononuclear cells fromM. bovis-infected cattle were stimulated in vitro with a recombinant ESAT-6 (rESAT-6)-CFP10 fusion protein and compared to responses induced byM. bovis-derived purified protein derivative. Following antigenic stimulation, activation marker expression was evaluated. Significant proliferative responses (P< 0.05) were evident in CD4+, CD8+, immunoglobulin M-positive, and CD172a+cell fractions after 6 days of culture. Expression of CD25 and CD26 was increased (P< 0.05) on CD4+, CD8+, and γδ T-cell-receptor-positive cells. CD4+and CD8+cells also exhibited significant changes (P< 0.05) in expression of CD45 isoforms. Using a flow cytometry-based proliferation assay, it was determined that CD45R expression is downregulated (P< 0.05) and that CD45RO expression is upregulated (P< 0.05) on proliferating (i.e., activated) CD4+cells. Collectively, data indicate that recall immune responses directed toward the rESAT-6-CFP10 fusion protein or purified protein derivative are comparable and that recall to mycobacterial antigens correlates with a CD45RO+phenotype.
Enhancement of Innate and Cell-Mediated Immunity by Antimycobacterial Antibodies
Authors: de Vallière S. , Abate G. , Blazevic A. , Heuertz R. M. , Hoft D. F.
Published: September 2005

We investigated the ability of human antibodies induced byMycobacterium bovisbacillus Calmette-Guérin (BCG) vaccination to protect against mycobacterial infections. Serum samples containing mycobacterium-specific antibodies were obtained from volunteers who had received two intradermal BCG vaccinations 6 months apart. Significant increases in lipoarabinomannan (LAM)-specific immunoglobulin G (IgG) were detected after both the primary and booster vaccinations. Effects of mycobacterium-specific antibodies on surface binding and internalization of BCG by neutrophils and monocytes/macrophages were studied, using green fluorescent protein (gfp)-expressing BCG. Surface-bound gfp-expressing BCG were distinguished from intracellular BCG by surface labeling with LAM-specific monoclonal antibody. Internalization of BCG by phagocytic cells was shown to be significantly enhanced in postvaccination serum samples. Furthermore, the inhibitory effects of neutrophils and monocytes/macrophages on mycobacterial growth were significantly enhanced by BCG-induced antibodies. The growth-inhibiting effects of postvaccination sera were reversed by preabsorption of IgG with Protein G. Finally, the helper effects of antimycobacterial antibodies for the induction of cell-mediated immune responses were investigated. BCG-induced antibodies significantly enhanced proliferation and gamma interferon production in mycobacterium-specific CD4+and CD8+T cells, as well as the proportion of proliferating and degranulating CD8+T cells. We conclude that mycobacterium-specific antibodies are capable of enhancing both innate and cell-mediated immune responses to mycobacteria.
Cellular Mechanisms of the Adjuvant Activity of the Flagellin Component FljB ofSalmonella entericaSerovar Typhimurium To Potentiate Mucosal and Systemic Responses
Authors: Pino Oscar , Martin Michael , Michalek Suzanne M.
Published: September 2005

An expanding area of interest is the utilization of microbe-based components to augment mucosal and systemic immune responses to target antigens. Thus, the aim of the present study was to assess if the flagellin component FljB fromSalmonella entericaserovar Typhimurium could act as a mucosal adjuvant and then to determine the cellular mechanism(s) by which FljB mediates its adjuvant properties. To determine if FljB could act as a mucosal adjuvant, mice were immunized by the intranasal (i.n.) route with antigen alone or in conjunction with FljB. Additionally, we assessed how FljB affected the levels of the costimulatory molecules B7-1 and B7-2 on dendritic cells by flow cytometry and determined the functional role these costimulatory molecules played in the adjuvant properties of FljB in vivo. Mice immunized by the i.n. route with antigen and FljB exhibited significantly elevated levels of mucosal and systemic antibody and CD4+-T-cell responses compared to mice given antigen only. Stimulation of dendritic cells in vitro with FljB resulted in a pronounced increase in the surface expression of B7-1 and B7-2. The percentage of dendritic cells expressing B7-2 but not B7-1 increased significantly when stimulated with FljB over a concentration range of 10 to 10,000 ng/ml. Immunization of wild-type and B7-1, B7-2, and B7-1/2 knockout mice by the i.n. route revealed that the ability of FljB to increase B7-2 expression is largely responsible for its adjuvant effect in vivo. These findings demonstrate that FljB can act as an effective mucosal adjuvant and that its ability to enhance the level of B7-2 expression is predominantly responsible for its adjuvant properties.
Human Dendritic Cell Activity againstHistoplasma capsulatumIs Mediated via Phagolysosomal Fusion
Authors: Gildea Lucy A. , Ciraolo Georgianne M. , Morris Randal E. , Newman Simon L.
Published: September 2005

Histoplasma capsulatumis a fungal pathogen that requires the induction of cell-mediated immunity (CMI) for host survival. We have demonstrated that human dendritic cells (DC) phagocytoseH. capsulatumyeasts and, unlike human macrophages (Mø) that are permissive for intracellular growth, DC killed and degraded the fungus. In the present study, we sought to determine whether the mechanism(s) by which DC killHistoplasmais via lysosomal hydrolases, via the production of toxic oxygen metabolites, or both. Phagosome-lysosome fusion (PL-fusion) was quantified by using fluorescein isothiocyanate-dextran and phase and fluorescence microscopy and by electron microscopy with horseradish peroxidase colloidal gold to label lysosomes. Unlike Mφ,Histoplasma-infected DC exhibited marked PL-fusion. The addition of suramin toHistoplasma-infected DC inhibited PL-fusion and DC fungicidal activity. Incubation ofHistoplasma-infected DC at 18°C also concomitantly reduced PL-fusion and decreased the capacity of DC to kill and degradeH. capsulatumyeasts. Further, culture ofHistoplasma-infected DC in the presence of bafilomycin, an inhibitor of the vacuolar ATPase, did not block DC anti-Histoplasmaactivity, indicating that phagosome acidification was not required for lysosome enzyme activity. In contrast, culture ofHistoplasma-infected DC in the presence of inhibitors of the respiratory burst or inhibitors of NO synthase had little to no effect on DC fungicidal activity. These data suggest that the major mechanism by which human DC mediate anti-Histoplasmaactivity is through the exposure of yeasts to DC lysosomal hydrolases. Thus, DC can override one of the strategies used byH. capsulatumyeasts to survive intracellularly within Mø.
Induction of Protective Immunity to Anthrax Lethal Toxin with a Nonhuman Primate Adenovirus-Based Vaccine in the Presence of Preexisting Anti-Human Adenovirus Immunity
Authors: Hashimoto Masahiko , Boyer Julie L. , Hackett Neil R. , Wilson James M. , Crystal Ronald G.
Published: September 2005

Prevention or therapy for bioterrorism-associated anthrax infections requires rapidly acting effective vaccines. We recently demonstrated (Y. Tan, N. R. Hackett, J. L. Boyer, and R. G. Crystal, Hum. Gene Ther.
14:
1673-1682, 2003) that a single administration of a recombinant serotype 5 adenovirus (Ad) vector expressing anthrax protective antigen (PA) provides rapid protection against anthrax lethal toxin challenge. However, approximately 35 to 50% of humans have preexisting neutralizing antibodies against Ad5. This study assesses the hypothesis that a recombinant adenovirus vaccine based on the nonhuman primate-derived serotype AdC7, against which humans do not have immunity, expressing PA (AdC7PA) will protect against anthrax lethal toxin even in the presence of preexisting anti-Ad5 immunity. Naive and Ad5-immunized BALB/c mice received (intramuscularly) 10
8
to 10
11
particle units (PU) of AdC7PA, Ad5PA (a human serotype Ad5-based vector expressing a secreted form of PA), or AdNull (an Ad5 vector with no transgene). Robust anti-PA immunoglobulin G and neutralizing antibodies were detected by 2 to 4 weeks following administration of AdC7PA to naive or Ad5 preimmunized mice, whereas low anti-PA titers were detected in Ad5-preimmunized mice following administration of Ad5PA. To assess protection in vivo, naive or mice previously immunized against Ad5 were immunized with AdC7PA or Ad5PA and then challenged with a lethal intravenous dose of
Bacillus anthracis
lethal toxin. Whereas Ad5PA protected naive mice against challenge with
B. anthracis
lethal toxin, Ad5PA was ineffective in mice that were previously immunized against Ad5. In contrast, AdC7PA functioned effectively not only to protect naive mice but also to protect Ad5-preimmunized mice, with 100% survival after lethal toxin challenge. These data suggest the nonhuman-based vector AdC7PA is an effective vaccine for the development of protective immunity against
B. anthracis
and importantly functions as a “sero-switch” base for an adenovirus vaccine to function in the context of preexisting anti-Ad immunity.
Identification of New Antigens in Visceral Leishmaniasis by Expression Cloning and Immunoblotting with Sera of Kala-Azar Patients from Bihar, India
Authors: Theinert Stephan M. , Basu Rajatava , Forgber Michael , Roy Syamal , Sundar Shyam , Walden Peter
Published: September 2005

Sera of kala-azar patients from Bihar, India, were used to identify
Leishmania donovani
antigens encoded by a phage expression library. Ten antigens were identified, five of which have not been described as leishmania antigens before. The antigens specifically react with sera of leishmania-infected patients but not of toxoplasma- or plasmodium-infected patients.
Digalactoside Expression in the Lipopolysaccharide of
Haemophilus influenzae
and Its Role in Intravascular Survival
Authors: Griffin Ruth , Bayliss Chris D. , Herbert Mark A. , Cox Andrew D. , Makepeace Katherine , Richards James C. , Hood Derek W. , Moxon E. Richard
Published: September 2005

Digalactoside (galα-1-4 galβ) structures of the lipopolysaccharide (LPS) of
Haemophilus influenzae
are implicated in virulence. A confounding factor is that tetranucleotide repeats within the
lic2A
,
lgtC
, and
lex2
genes mediate phase-variable expression of the digalactosides. By deleting these repeats, we constructed recombinant strains of RM153 constitutively expressing either one or two LPS digalactosides. Expression of two digalactosides, rather than one, was associated with increased virulence of
H. influenzae
in vivo.