bluuebunny/crossref_metadata_2025 huggingface dataset:
Surgical Treatment of Vulvar Vestibulitis Syndrome: Outcome Assessment Derived from a Postoperative Questionnaire
Authors: Goldstein Andrew T. , Klingman Daisy , Christopher Kurt , Johnson Crista , Marinoff Stanley C.
Published: August 2006

Introduction

Vulvar vestibulitis syndrome (VVS) is the most common pathology in women with sexual pain. Surgery for VVS was first described in 1981. Despite apparently high surgical success rates, most review articles suggest that surgery should be used only “as a last resort.” Risks of complications such as bleeding, scarring, and recurrence of symptoms are often used to justify these cautionary statements. However, there are little data in the peer-reviewed literature to justify this cautionary statement.

Aims

To determine patient satisfaction with vulvar vestibulectomy for VVS and the rate of complications with this procedure.

Methods

Women who underwent a complete vulvar vestibulectomy with vaginal advancement by one of three different surgeons were contacted via telephone by an independent researcher between 12 and 72 months after surgery.

Main Outcome Measures

The primary outcome measurement of surgical success was overall patient satisfaction with surgery. Additional secondary outcome measurements included improvement in dyspareunia, changes in coital frequency, and occurrence of surgical complications.

Results

In total, 134 women underwent surgery in a 5-year period. An independent research assistant was able to contact 106 women, and 104 agreed to participate in the study. Mean duration since surgery was 26 months. A total of 97 women (93%) were satisfied, or very satisfied, with the outcome of their surgery. Only three patients (3%) reported persistently worse symptoms after surgery and only seven (7%) reported permanent recurrence of any symptoms after surgery. Prior to surgery, 72% of the women were completely apareunic; however, after surgery, only 11% were unable to have intercourse.

Discussion

In this cohort of patients, there was a high degree of satisfaction with surgery for VVS. In addition, the risks of complications with this procedure were low, and most complications were transient and the risk of recurrence after surgery was also found to be low.
Purification and properties of blackberry chlorotic ringspot, a new virus species in subgroup 1 of the genus Ilarvirus found naturally infecting blackberry in the UK
Authors: Jones A.T. , McGavin W.J. , Gepp V. , Zimmerman M.T. , Scott S.W.
Published: August 2006

A mechanically transmissible virus was isolated from Bedford Giant blackberry plants showing chlorotic mottling and ringspot symptoms growing in Scotland. It infected several herbaceous test plants, many of them symptomlessly. This virus was also transmitted to several Rubus species and cultivars by graft inoculation with scions from the field‐infected Bedford Giant plant. Most grafted plants were infected symptomlessly, but Himalaya Giant blackberry and the hybrid berry Tayberry developed symptoms similar to those in the infected Bedford Giant plant. In the sap of infected Chenopodium quinoa, the virus lost infectivity when diluted 10−4 but not 10−3, after 6 h and 48 h when kept at 20°C and 4°C, respectively, but was infective for more than 8 days when kept at −15°C. Preparations of purified virus from infected C. quinoa or spinach sedimented as three major nucleoprotein components and consisted of quasi‐isometric particles that varied in size from 24 to 32 nm in diameter and that were not penetrated by negative stain. Such virus particle preparations contained a major polypeptide of ca 28 kDa and three single‐stranded RNA species of estimated size 3.2, 2.8 and 2.1 kb. The complete sequence of the largest RNA (RNA 1, 3478 nt) and the partial sequence of the other RNAs (1863 and 2102 nt long, respectively) were determined and compared with sequences in databases. These findings, together with the biological and biochemical properties of this virus, indicate that it should be regarded as a distinct species in subgroup 1 of the genus Ilarvirus even though it was serologically unrelated to existing members of this subgroup. The virus showed a very distant serological relationship with prune dwarf virus (PDV) but differed significantly from it in the amino acid sequence of its coat protein, experimental host range and symptomatology and was unrelated to PDV at the molecular level. The virus, tentatively named blackberry chlorotic ringspot virus, is therefore a newly described virus and the first ilarvirus found naturally infecting Rubus in the UK.
Plant extract contact toxicities to various developmental stages of Colorado potato beetles (Coleoptera: Chrysomelidae)
Authors: Gökçe A. , Whalon M.E. , Çam H. , Yanar Y. , Demirtaş İ. , Gören N.
Published: August 2006

The contact toxicities of methanol extracts from the nine plant species Hedera helix, Artemisia vulgaris, Xanthium strumarium, Humulus lupulus, Sambucus nigra, Chenopodium album, Salvia officinalis, Lolium temulentum and Verbascum songaricum were tested on the developmental stages of Colorado potato beetle (CPB) (Leptinotarsa decemlineata). About 2 mL of plant extract, 40% (w/w), was applied to the first instar to fourth instar larvae and adult beetles using a Potter spray tower. Most of the tested plant extracts caused relatively low mortality in all the beetle instars. Among the plant extracts, H. lupulus extract was the most toxic to all stages of the insect, except for the adult beetles. Larval mortality ranged from 40% in the fourth instars to 84% in the third instars. In a second series of experiments, dose–response bioassays using H. lupulus extract produced lethal concentration 50 (LC50) values ranging from 10%, 12%, 17% to 46% (w/w) active ingredient (plant material) for instars 1–4, respectively. This increasing mortality trend, however, did not extend to the adult stage where even the maximum dose of 40% plant material did not provide sufficient mortality to allow estimation of a LC50. These results demonstrated that the extract from H. lupulus has potential as an active ingredient in biological pesticides developed to manage larval instars of the CPB. The potential uses of this plant extract may be in conventional and organic pest management or as part of a mixture of plant extracts or conventional insecticides. Before extracts can be considered as biological control agents, their impact on natural enemies should be assessed.
A high-significance detection of non-Gaussianity in the WMAP 3-yr data using directional spherical wavelets
Authors: McEwen J. D. , Hobson M. P. , Lasenby A. N. , Mortlock D. J.
Published: August 2006

We repeat the directional spherical real Morlet wavelet analysis, used to detect non-Gaussianity in the Wilkinson Microwave Anisotropy Probe (WMAP) 1-yr data, on the WMAP 3-yr data. The non-Gaussian signal previously detected is indeed present in the 3-yr data, although the significance of the detection is reduced. Using our most conservative method for constructing significance measures, we find that the significance of the detection of non-Gaussianity drops from 98.3 ± 0.4 to 94.9 ± 0.7 per cent; the significance drops from 99.3 ± 0.3 to 97.2 ± 0.5 per cent using a method based on the χ2 statistic. The wavelet analysis allows us to localize most likely sources of non-Gaussianity on the sky. We detect very similar localized regions in the WMAP 1-yr and 3-yr data, although the regions extracted appear more pronounced in the 3-yr data. When all localized regions are excluded from the analysis, the 3-yr data are consistent with Gaussianity.
Isothermal shocks in Abell 2199 and 2A 0335+096?
Authors: Sanders J. S. , Fabian A. C.
Published: August 2006

We report on a partially circular X-ray surface brightness discontinuity found at about 55 kpc from the centre of Abell 2199 with Chandra X-ray Observatory observations. Unlike cold fronts found in other clusters, the feature shows no significant temperature change across it but has an apparent density jump. We therefore identify it as a weak isothermal shock associated with the central active galactic nucleus and the inflation of its radio bubbles, as found in the Perseus cluster. We examine a similar feature at 40 kpc radius found by Mazzotta et al. in 2A 0335+096, and conclude that it too may be an isothermal shock. The change in density if these are shocks implies a Mach number of ∼1.5. If the isothermal nature of these features is confirmed by deeper observations, the implication is that such shocks are common in clusters of galaxies, and are an important mechanism for the transport of energy from a central supermassive black hole into the cluster core.
A model for the infrared emission of FSC 10214+4724
Authors: Efstathiou Andreas
Published: August 2006

A model for the infrared emission of the high-redshift ultraluminous infrared galaxy FSC 10214+4724 is presented. The model assumes three components of emission: a dusty torus viewed edge-on, clouds that are associated with the narrow-line region and a highly obscured starburst. It is demonstrated that the presence of clouds in the narrow-line region, with a covering factor of 17 per cent, can explain why the mid-infrared spectrum of FSC 10214+4724 shows a silicate feature in emission despite the fact that its torus is viewed edge-on. It is also shown that the same model, but with the torus viewed face-on, predicts a spectrum with silicate emission features that is characteristic of the spectra of quasars recently observed with Spitzer.
Selective Peptide Chain Extension at the C‐terminus of Aspartic and Glutamic Acids Utilizing N‐protected (α‐aminoacyl)benzotriazoles
Authors: Katritzky Alan R. , Todadze Ekaterina , Shestopalov Alexander A. , Cusido Janet , Angrish Parul
Published: August 2006

Aspartic and glutamic acids were selectively extended at each of the alternative C‐terminals under mild conditions to afford diverse natural and unnatural N‐protected dipeptides and tripeptides in yields of 73–96%. The reactions between N‐protected (α‐aminoacyl)benzotriazoles and free amino acids or dipeptides proceeded with complete retention of chirality as supported by parallel experiments involving d‐Ala, l‐Ala, and dl‐Ala in the preparation of dipeptides and tripeptides, monitored by NMR and HPLC analyses.
PHYSIOLOGICAL AND BEHAVIORAL DEVELOPMENT IN DELPHINID CALVES: IMPLICATIONS FOR CALF SEPARATION AND MORTALITY DUE TO TUNA PURSE‐SEINE SETS
Authors: Noren Shawn R. , Edwards Elizabeth F.
Published: August 2006

Abstract

Tuna purse‐seiners in the eastern tropical Pacific (ETP) capture yellowfin tuna by chasing and encircling herds of associated dolphins. This fishery has caused mortality in 14 dolphin species (20 stocks) and has led to significant depletions of at least three stocks. Although observed dolphin mortality is currently low, set frequency remains high and dolphin stocks are not recovering at expected rates. Mortality of nursing calves permanently separated from their mothers during fishery operations may be an important factor in the lack of population recovery, based on the recent discovery that calves do not accompany 75%–95% of lactating females killed in the purse‐seine nets. We assessed age‐specific potential for mother–calf separations and subsequent mortality of calves by reviewing and synthesizing published data on physiological and behavioral development in delphinids from birth through 3 yr postpartum. Results indicate that evasive behavior of mothers, coupled with the developmental state of calves, provides a plausible mechanism for set‐related mother–calf separations and subsequent mortality of calves. Potential for set‐related separation and subsequent mortality is highest for 0–12‐mo‐old dolphins and becomes progressively lower with age as immature dolphins approach adult stamina and attain independence.
Modeling the Transport of Low-Molecular-Weight Penetrants Within Polymer Matrix Composites
Authors: Bond David A. , Smith Paul A.
Published: August 2006

In 1855 Fick reported on the diffusion of liquid through a membrane and proposed that there was an analogy between this process and that of heat conduction allowing him to transcribe the mathematical equation for heat conduction derived in 1822 by Fourier into a form to represent this diffusion of liquid. This model, known as Fickian diffusion, has become the baseline against which the characteristics of liquid diffusion are measured to the point where anomalous diffusion is known generically as non-Fickian. Numerous authors have attempted to develop models to cover all aspects of non-Fickian diffusion resulting in a very large number of models that consider the effect of parameters as varied as the chemical makeup, geometric dimensions, environmental history, stress state, and damage status of the material, as well as the likelihood of multiple diffusion mechanisms being responsible for transport of the water molecules. Of particular interest to structural engineers is the transport of moisture in polymer matrix composites owing to the plasticizing effect the moisture may have on the composite and the potential for the moisture to induce localized damage. This paper reviews analytical models that are relevant to the transport of moisture in structural composites. In doing so the benefits and limitations of the various models and techniques are presented in order to provide a reference for scientists and engineers attempting to describe the kinetics of moisture in composites accurately. There are 160 references cited in this review article.
Constructal Theory: From Engineering to Physics, and How Flow Systems Develop Shape and Structure
Authors: Reis A. Heitor
Published: August 2006

Constructal theory and its applications to various fields ranging from engineering to natural living and inanimate systems, and to social organization and economics, are reviewed in this paper. The constructal law states that if a system has freedom to morph it develops in time the flow architecture that provides easier access to the currents that flow through it. It is shown how constructal theory provides a unifying picture for the development of flow architectures in systems with internal flows (e.g., mass, heat, electricity, goods, and people). Early and recent works on constructal theory by various authors covering the fields of heat and mass transfer in engineered systems, inanimate flow structures (river basins, global circulations) living structures, social organization, and economics are reviewed. The relation between the constructal law and the thermodynamic optimization method of entropy generation minimization is outlined. The constructal law is a self-standing principle, which is distinct from the Second Law of Thermodynamics. The place of the constructal law among other fundamental principles, such as the Second Law, the principle of least action and the principles of symmetry and invariance is also presented. The review ends with the epistemological and philosophical implications of the constructal law.
Scaling Laws and Multiscale Approach in the Mechanics of Heterogeneous and Disordered Materials
Authors: Carpinteri Alberto , Cornetti Pietro , Puzzi Simone
Published: August 2006

The present paper is a review of research carried out on scaling laws and multiscaling approach in the mechanics of heterogeneous and disordered materials in the last two decades, especially at the Politecnio di Torino. The subject encompasses theoretical, numerical and experimental aspects. The research followed two main directions. The first one concerns the implementation and the development of the cohesive crack model, which has been shown to be able to simulate experiments on concrete like materials and structures. It is referred to as the dimensional analysis approach, since it succeeds in capturing the ductile-to-brittle transition by increasing the structural size owing to the different physical dimensions of two material parameters: the tensile strength and the fracture energy. The second research direction aims at capturing the size-scale effects of quasibrittle materials, which show fractal patterns in the failure process. This approach is referred to as the renormalization group (or fractal) approach and leads to a scale-invariant fractal cohesive crack model. This model is able to predict the size effects even in tests where the classical approach fails, e.g., the direct tension test. Within this framework and introducing the fractional calculus, it is shown how the Principle of Virtual Work can be rewritten in its fractional form, thus obtaining a scaling law not only for the tensile strength and the fracture energy, but also for the critical strain.
Expression and Function of a Family of Transmembrane Kinases from the Protozoan Parasite
Entamoeba histolytica
Authors: Mehra Alka , Fredrick Jesse , Petri William A. , Bhattacharya Sudha , Bhattacharya Alok
Published: August 2006

The signaling proteome of
Entamoeba histolytica
is made of transmembrane kinases (TMKs) that are rarely found in unicellular eukaryotes. There are 90 TMK genes reported for
E. histolytica
, and these have been grouped into nine distinct families based on motifs present on both extracellular and kinase domains. Of these, the B1 family was chosen for further analysis. Genomic sequencing revealed the presence of 28 members belonging to this family. Genes corresponding to the majority of these were truncated and not considered for further analysis. Only five members were full length and contained both extracellular and cytosolic kinase domains. BLAST analysis revealed the presence of homologs of these B1 TMKs in the nonpathogenic
Entamoeba dispar
. However, the ligand binding domains of the orthologous B1 TMKs of the two species showed considerable divergence, indicating the possibility of a correlation with the pathogenic potential of the organism. Only two of the five full-length copies (B1.I.1 and B1.I.2) were expressed in
E. histolytica
under the culture conditions used. Antisera generated against the extracellular domain of B1.I.1 stained the cell surface, particularly the areas of contact between the trophozoites. Staining was also seen in the frontal and posterior regions of the motile amoeba. An amoebic cell line expressing a truncated version of the B1.I.1 that lacked the kinase domain was generated. Inducible expression of the truncated TMK resulted in a decrease in cellular proliferation and an increase in sensitivity to serum starvation. Our data indicate that the B1.I class of TMKs is involved in parasite proliferation.
The
Bacteroides fragilis
Toxin Binds to a Specific Intestinal Epithelial Cell Receptor
Authors: Wu Shaoguang , Shin Jai , Zhang Guangming , Cohen Mitchell , Franco Augusto , Sears Cynthia L.
Published: August 2006

The
Bacteroides fragilis
toxin (BFT) is the only known virulence factor of enterotoxigenic
B. fragilis
. BFT has previously been shown to act, at least in part, through cleavage of the intercellular adhesion protein E-cadherin. A specific cellular receptor for BFT has not been identified. The goal of this study was to determine if the initial interaction of BFT with intestinal epithelial cells was consistent with binding to a specific cellular receptor. Purified BFT was labeled with a fluorophore or iodide to assess specific cellular binding and the properties of BFT cellular binding. BFT binds specifically to intestinal epithelial cell lines in vitro in a polarized manner. However, specific binding occurs only at 37°C and requires BFT metalloprotease activity. The BFT receptor is predicted to be a membrane protein other than E-cadherin or a known protease-activated receptor (PAR1 to PAR4). BFT binding is resistant to acid washing, suggesting an irreversible interaction. Sugar or lipid residues do not appear to be involved in the mechanism of BFT cellular binding, but binding is sensitive to membrane cholesterol depletion. We conclude that intestinal epithelial cells in vitro possess a specific membrane BFT receptor that is distinct from E-cadherin. The data favor a model in which the metalloprotease domain of BFT processes its receptor protein, initiating cellular signal transduction that mediates the biological activity of BFT. However, activation of recognized protease-activated receptors does not mimic or block BFT biological activity or binding, suggesting that additional protease-activated receptors on intestinal epithelial cells remain to be identified.
The
Salmonella enterica
Serovar Typhi Type IVB Self-Association Pili Are Detached from the Bacterial Cell by the PilV Minor Pilus Proteins
Authors: Tam Connie K. P. , Morris Christina , Hackett Jim
Published: August 2006

Salmonella enterica
serovar Typhi and some strains (Vi
+
) of serovar Dublin use type IVB pili to facilitate bacterial self-association, but only when the PilV proteins (potential minor pilus proteins) are not synthesized. Pilus-mediated self-association may be important in the pathogenesis of enteric fever. We have shown previously that the extent of DNA supercoiling controls the rate of Rci-catalyzed inversion of a DNA fragment which includes the C-terminal portions of the PilV proteins. This inversion therefore controls PilV synthesis as a high inversion rate prohibits transcription of
pilV
-encoding DNA. Here, we describe the manner in which PilV protein expression inhibits bacterial self-association and present data which suggest that incorporation of one or a few PilV protein molecules into a growing pilus, comprised of PilS subunits, causes the pilus to detach at the bacterial membrane. The bacteria are then unable to self-associate. We suggest that this phenomenon may be relevant to the pathogenesis of typhoid fever.
Infection of Human Endothelial Cells with Spotted Fever Group Rickettsiae Stimulates Cyclooxygenase 2 Expression and Release of Vasoactive Prostaglandins
Authors: Rydkina Elena , Sahni Abha , Baggs Raymond B. , Silverman David J. , Sahni Sanjeev K.
Published: August 2006

Rickettsiae, a diverse group of obligately intracellular gram-negative bacteria, include etiologic agents of the spotted fever and typhus groups of diseases. Rocky Mountain spotted fever and boutonneuse fever, due toRickettsia rickettsiiandR. conorii, respectively, are characterized by widespread infection of the vascular endothelium, microvascular injury, and vasculitis. Cultured human endothelial cells (EC) are highly susceptible to infection and respond by altering the expression of adhesion molecules, regulatory cytokines, and the antioxidant enzyme heme oxygenase (HO). In the vasculature, HO regulates the cyclooxygenase (COX) enzymes, among which the inducible isozyme COX-2 facilitates the synthesis of prostaglandins (PGs). Using in vitro and ex vivo models of infection, we demonstrate here thatR. rickettsiiinfection of human EC causes robust induction of COX-2 mRNA and protein expression but has no apparent effect on the constitutive COX-1 isoform. Cells infected with viable rickettsiae consistently displayed significantly increased secretion of 6-keto-PGF1αand PGE2.R. rickettsii-induced COX-2 was sensitive to inhibitors of de novo transcription and the pyridinylimidazole-based compound SB 203580, suggesting that this transcriptional host cell response involves signaling through p38 mitogen-activated protein kinase. PG production by infected cells was abrogated by NS 398 (a selective COX-2 inhibitor) and indomethacin (a pan-COX inhibitor). Immunohistochemical staining of sections of infected umbilical cords and corresponding uninfected controls revealed comparatively more intense and abundant staining for COX-2 in infected endothelia. Induction of the endothelial COX-2 system and the resultant enhanced release of vasoactive PGs may contribute to the regulation of inflammatory responses and vascular permeability changes during spotted fever rickettsioses.
Yersinia pestis
YopJ Suppresses Tumor Necrosis Factor Alpha Induction and Contributes to Apoptosis of Immune Cells in the Lymph Node but Is Not Required for Virulence in a Rat Model of Bubonic Plague
Authors: Lemaître Nadine , Sebbane Florent , Long Daniel , Joseph Hinnebusch B.
Published: August 2006

The virulence of the pathogenic
Yersinia
species depends on a plasmid-encoded type III secretion system that transfers six Yop effector proteins into host cells. One of these proteins, YopJ, has been shown to disrupt host cell signaling pathways involved in proinflammatory cytokine production and to induce macrophage apoptosis in vitro. YopJ-dependent apoptosis in mesenteric lymph nodes has also been demonstrated in a mouse model of
Yersinia pseudotuberculosis
infection. These results suggest that YopJ attenuates the host innate and adaptive immune response during infection, but the role of YopJ during bubonic plague has not been completely established. We evaluated the role of
Yersinia pestis
YopJ in a rat model of bubonic plague following intradermal infection with a fully virulent
Y. pestis
strain and an isogenic
yopJ
mutant. Deletion of
yopJ
resulted in a twofold decrease in the number of apoptotic immune cells in the bubo and a threefold increase in serum tumor necrosis factor alpha levels but did not result in decreased virulence, systemic spread, or colonization levels in the spleen and blood. Our results indicate that YopJ is not essential for bubonic plague pathogenesis, even after peripheral inoculation of low doses of
Y. pestis
. Instead, the effects of YopJ appear to overlap and augment the immunomodulatory effects of other
Y. pestis
virulence factors.
Lack of Eosinophil Peroxidase or Major Basic Protein Impairs Defense against Murine Filarial Infection
Authors: Specht Sabine , Saeftel Michael , Arndt Manuela , Endl Elmar , Dubben Bettina , Lee Nancy A. , Lee James J. , Hoerauf Achim
Published: August 2006

Eosinophils are a hallmark of allergic diseases and helminth infection, yet direct evidence for killing of helminth parasites by their toxic granule products exists only in vitro. We investigated the in vivo roles of the eosinophil granule proteins eosinophil peroxidase (EPO) and major basic protein 1 (MBP) during infection with the rodent filariaLitomosoides sigmodontis. Mice deficient for either EPO or MBP on the 129/SvJ background developed significantly higher worm burdens than wild-type mice. Furthermore, the data indicate that EPO or MBP is involved in modulating the immune response leading to altered cytokine production during infection. Thus, in the absence of MBP, mice showed increased interleukin-10 (IL-10) production after stimulation of macrophages from the thoracic cavity where the worms reside. In addition to elevated IL-10 levels, EPO−/−mice displayed strongly increased amounts of the Th2 cytokine IL-5 by CD4 T cells as well as a significantly higher eosinophilia. Interestingly, a reduced ability to produce IL-4 in the knockout strains could even be seen in noninfected mice, arguing for different innate propensities to react with a Th2 response in the absence of either EPO or MBP. In conclusion, both of the eosinophil granule products MBP and EPO are part of the defense mechanism against filarial parasites. These data suggest a hitherto unknown interaction between eosinophil granule proteins, defense against filarial nematodes, and cytokine responses of macrophages and CD4 T cells.
Pulmonary Lymphatics Are Primary Sites of
Mycobacterium tuberculosis
Infection in Guinea Pigs Infected by Aerosol
Authors: Basaraba Randall J. , Smith Erin E. , Shanley Crystal A. , Orme Ian M.
Published: August 2006

Mycobacterium tuberculosis
causes a lymphatic vasculitis in the lungs of guinea pigs infected by a low-dose aerosol. This observation suggests that in addition to being a direct conduit from the lungs to the regional lymph nodes, pulmonary lymphatics are themselves sites of infection and could be the site of latent infection.
Uropathogenic
Escherichia coli
Induces Extrinsic and Intrinsic Cascades To Initiate Urothelial Apoptosis
Authors: Klumpp David J. , Rycyk Matthew T. , Chen Michael C. , Thumbikat Praveen , Sengupta Shomit , Schaeffer Anthony J.
Published: August 2006

A murine model of urinary tract infection identified urothelial apoptosis as a key event in the pathogenesis mediated by uropathogenic
Escherichia coli
(UPEC), yet the mechanism of this important host response is not well characterized. We employed a culture model of UPEC-urothelium interactions to examine the biochemical events associated with urothelial apoptosis induced by the UPEC strain NU14. NU14 induced DNA cleavage within 5 h that was inhibited by the broad caspase inhibitor ZVAD, and urothelial caspase 3 activity was induced within 3 h of exposure to type 1 piliated NU14 and was dependent upon interactions mediated by the type 1 pilus adhesin FimH. Flow cytometry experiments using chloromethyl-X-rosamine and Indo-1 revealed FimH-dependent mitochondrial membrane depolarization and elevated [Ca
2+
]
in
, respectively, indicating activation of the intrinsic apoptotic pathway. Consistent with this possibility, overexpression of Bcl
XL
inhibited NU14 activation of caspase 3. Immunoblotting, caspase inhibitors, and caspase activity assays implicated both caspase 2 and caspase 8 in apoptosis, suggesting the involvement of the intrinsic and extrinsic apoptotic cascades. To reconcile the apparent activation of both extrinsic and intrinsic pathways, we examined Bid-green fluorescent protein localization and observed translocation from the cytosol to mitochondria in response to either NU14 or purified FimH. These data suggest that FimH acts as a tethered toxin of UPEC that activates caspase-dependent urothelial apoptosis via direct induction of the extrinsic pathway and that the intrinsic pathway is activated indirectly as a result of coupling by caspase 8-mediated Bid cleavage.
Ligand-Signaled Upregulation of
Enterococcus faecalis ace
Transcription, a Mechanism for Modulating Host-
E. faecalis
Interaction
Authors: Nallapareddy Sreedhar R. , Murray Barbara E.
Published: August 2006

Enterococcus faecalis
, the third most frequent cause of bacterial endocarditis, appears to be equipped with diverse surface-associated proteins showing structural-fold similarity to the immunoglobulin-fold family of staphylococcal adhesins. Among the putative
E. faecalis
surface proteins, the previously characterized adhesin Ace, which shows specific binding to collagen and laminin, was detectable in surface protein preparations only after growth at 46°C, mirroring the finding that adherence was observed in 46°C, but not 37°C, grown
E. faecalis
cultures. To elucidate the influence of different growth and host parameters on
ace
expression, we investigated
ace
expression using
E. faecalis
OG1RF grown in routine laboratory media (brain heart infusion) and found that
ace
mRNA levels were low in all growth phases. However, quantitative reverse transcription-PCR showed 18-fold-higher
ace
mRNA amounts in cells grown in the presence of collagen type IV compared to the controls. Similarly, a marked increase was observed when cells were either grown in the presence of collagen type I or serum but not in the presence of fibrinogen or bovine serum albumin. The production of Ace after growth in the presence of collagen type IV was demonstrated by immunofluorescence microscopy, mirroring the increased
ace
mRNA levels. Furthermore, increased Ace expression correlated with increased collagen and laminin adhesion. Collagen-induced Ace expression was also seen in three of three other
E. faecalis
strains of diverse origins tested, and thus it appears to be a common phenomenon. The observation of host matrix signal-induced adherence of
E. faecalis
may have important implications on our understanding of this opportunistic pathogen.
Temperature-Regulated Microcolony Formation byBurkholderia pseudomalleiRequirespilAand Enhances Association with Cultured Human Cells
Authors: Boddey Justin A. , Flegg Cameron P. , Day Chris J. , Beacham Ifor R. , Peak Ian R.
Published: August 2006

Burkholderia pseudomalleiis the causative agent of melioidosis, a potentially fatal disease that is endemic to Northern Australia and Southeast Asia and is acquired from soil or water. Adherence ofB. pseudomallei08 to cultured cells increases dramatically following prior growth at 30°C or less compared to that following prior growth at 37°C. Here, we show that this occurs almost entirely as the result of microcolony formation (bacterium-bacterium interactions) following growth at 27°C but not at 37°C, which considerably enhances bacterial association with eukaryotic cells. Further, we demonstrate that the type IVA pilin-encoding gene,pilA, is essential for microcolony development byB. pseudomallei08, and thus optimum association with eukaryotic cells, but is not required for direct adherence (bacterium-cell interactions). In contrast, although theB. pseudomalleigenome sequence strain, K96243, also contains transcriptionally activepilA, microcolony formation rarely occurs following growth at either 27°C or 37°C and cell association occurs significantly less than with strain 08. Analysis ofpilAtranscription in 08 identified thatpilAis dramatically upregulated under microcolony-forming conditions, viz., growth at low temperature, and association with eukaryotic cells; the pattern of transcription ofpilAin K96243 differed from that in 08. Our study also suggests that biofilm formation byB. pseudomallei08 and K96243 on polyvinylchloride is not mediated bypilA. Adherence and microcolony formation, andpilAtranscription, vary between strains, consistent with known genomic variation inB. pseudomallei, and these phenotypes may be relevant to colonization from the environment.
Staphylococcus aureus
-Induced Corneal Inflammation Is Dependent on Toll-Like Receptor 2 and Myeloid Differentiation Factor 88
Authors: Sun Yan , Hise Amy G. , Kalsow Carolyn M. , Pearlman Eric
Published: August 2006

Toll-like receptors (TLRs) expressed by the corneal epithelium represent a first line of host defense to microbial keratitis. The current study examined the role of TLR2, TLR4, and TLR9 and the common adaptor molecule myeloid differentiation factor 88 (MyD88) in a
Staphylococcus aureus
model of corneal inflammation. The corneal epithelia of C57BL/6, TLR2
−/−
, TLR4
−/−
, TLR9
−/−
, and MyD88
−/−
mice were abraded using a trephine and epithelial brush and were exposed to heat- or UV-inactivated
S. aureus
clinical strain 8325-4 and other clinical isolates. Corneal thickness and haze were measured by in vivo confocal microscopy, neutrophil recruitment to the corneal stroma was quantified by immunohistochemistry, and cytokine production was measured by enzyme-linked immunosorbent assay. The exposure of corneal epithelium to
S. aureus
induced neutrophil recruitment to the corneal stroma and increased corneal thickness and haze in control C57BL/6 mice but not in TLR2
−/−
or MyD88
−/−
mice. The responses of TLR4
−/−
and TLR9
−/−
mice were similar to those of C57BL/6 mice.
S. aureus
-induced cytokine production by corneal epithelial cells and neutrophils was also significantly reduced in TLR2
−/−
mice compared with that in C57BL/6 mice. These findings indicate that
S. aureus
-induced corneal inflammation is mediated by TLR2 and MyD88 in resident epithelial cells and infiltrating neutrophils.
Bartonella quintana
Variably Expressed Outer Membrane Proteins Mediate Vascular Endothelial Growth Factor Secretion but Not Host Cell Adherence
Authors: Schulte Berit , Linke Dirk , Klumpp Sandra , Schaller Martin , Riess Tanja , Autenrieth Ingo B. , Kempf Volkhard A. J.
Published: August 2006

Bartonella quintana
causes trench fever, endocarditis, and the vasculoproliferative disorders bacillary angiomatosis and peliosis hepatis in humans. Little is known about the interaction of this pathogen with host cells. We attempted to elucidate the interaction of
B. quintana
with human macrophages (THP-1) and epithelial cells (HeLa 229). Remarkably, only
B. quintana
strain JK-31 induced secretion of vascular endothelial growth factor (VEGF) from THP-1 and HeLa 229 cells upon infection similar to the secretion induced by
B. henselae
Marseille, whereas other strains (
B. quintana
2-D70,
B. quintana
Toulouse, and
B. quintana
Munich) did not induce such secretion. Immunofluorescence testing and electron microscopy revealed that the
B. quintana
strains unable to induce VEGF secretion did not express the variable outer membrane proteins (Vomps) on their surfaces. Surprisingly, the increase in VEGF secretion mediated by
B. quintana
JK-31 was not paralleled by elevated host cell adherence rates compared with the rates for Vomp-negative
B. quintana
strains. Our results suggest that the Vomps play a leading role in the angiogenic reprogramming of host cells by
B. quintana
but not in the adherence to host cells.
Constitutive Expression of Outer Surface Protein C Diminishes the Ability ofBorrelia burgdorferiTo Evade Specific Humoral Immunity
Authors: Xu Qilong , Seemanapalli Sunita V. , McShan Kristy , Liang Fang Ting
Published: August 2006

The Lyme disease spirocheteBorrelia burgdorferireduces the expression of outer surface protein C (OspC) in response to the development of an anti-OspC humoral response, leading to the hypothesis that the ability to repress OspC expression is critical for the pathogen to proceed to chronic infection.B. burgdorferiwas genetically modified to constitutively express OspC by introducing an extraospCcopy fused with the borrelial flagellar gene (flaB) promoter. Such a genetic modification did not reduce infectivity or pathogenicity in severe combined immunodeficiency mice but resulted in clearance of infection by passively transferred OspC antibody. Spirochetes with constitutiveospCexpression were unable to establish chronic infections in immunocompetent mice unless they had undergone very destructive mutations in the introducedospCcopy. Two escape mutants were identified; one had all 7 bp deleted between the putative ribosome-binding site and the start codon, ATG, causing a failure in translational initiation, and the other mutant had an insertion of 2 bp between nucleotides 315 and 316, resulting in a nonsense mutation at codon 108. Thus, the ability ofB. burgdorferito repressospCexpression during mammalian infection allows the pathogen to avoid clearance and to preserve the integrity of the important gene for subsequent utilization during its enzootic life cycle.
Characterization of the Receptor-Ligand Pathways Important for Entry and Survival ofFrancisella tularensisin Human Macrophages
Authors: Balagopal Ashwin , MacFarlane Amanda Shearer , Mohapatra Nrusingh , Soni Shilpa , Gunn John S. , Schlesinger Larry S.
Published: August 2006

Inhalational pneumonic tularemia, caused byFrancisella tularensis, is lethal in humans.F. tularensisis phagocytosed by macrophages followed by escape from phagosomes into the cytoplasm. Little is known of the phagocytic mechanisms forFrancisella, particularly as they relate to the lung and alveolar macrophages. Here we examined receptors on primary human monocytes and macrophages which mediate the phagocytosis and intracellular survival ofF. novicida. F. novicidaassociation with monocyte-derived macrophages (MDM) was greater than with monocytes. Bacteria were readily ingested, as shown by electron microscopy. Bacterial association was significantly increased in fresh serum and only partially decreased in heat-inactivated serum. A role for both complement receptor 3 (CR3) and Fcγ receptors in uptake was supported by studies using a CR3-expressing cell line and by down-modulation of Fcγ receptors on MDM, respectively. Consistent with Fcγ receptor involvement, antibody in nonimmune human serum was detected on the surface ofFrancisella. In the absence of serum opsonins, competitive inhibition of mannose receptor (MR) activity on MDM with mannan decreased the association ofF. novicidaand opsonization ofF. novicidawith lung collectin surfactant protein A (SP-A) increased bacterial association and intracellular survival. This study demonstrates that human macrophages phagocytose moreFrancisellathan monocytes with contributions from CR3, Fcγ receptors, the MR, and SP-A present in lung alveoli.
Vaccinations with Recombinant Variants of
Aspergillus fumigatus
Allergen Asp f 3 Protect Mice against Invasive Aspergillosis
Authors: Ito James I. , Lyons Joseph M. , Hong Teresa B. , Tamae Daniel , Liu Yi-Kuang , Wilczynski Sharon P. , Kalkum Markus
Published: August 2006

A vaccine that effectively protects immunocompromised patients against invasive aspergillosis is a novel approach to a universally fatal disease. Here we present a rationale for selection and in vivo testing of potential protein vaccine candidates, based on the modification of an immunodominant fungal allergen for which we demonstrate immunoprotective properties. Pulmonary exposure to viable
Aspergillus fumigatus
conidia as well as vaccination with crude hyphal extracts protects corticosteroid-immunosuppressed mice against invasive aspergillosis (J. I. Ito and J. M. Lyons, J. Infect. Dis. 186:869-871, 2002). Sera from the latter animals contain antibodies with numerous and diverse antigen specificities, whereas sera from conidium-exposed mice contain antibodies predominantly against allergen Asp f 3 (and some against Asp f 1), as identified by mass spectrometry. Subcutaneous immunization with recombinant Asp f 3 (rAsp f 3) but not with Asp f 1 was protective. The lungs of Asp f 3-vaccinated survivors were free of hyphae and showed only a patchy low-density infiltrate of mononuclear cells. In contrast, the nonimmunized animals died with invasive hyphal elements and a compact peribronchial infiltrate of predominately polymorphonuclear leukocytes. Three truncated versions of rAsp f 3, spanning amino acid residues 15 to 168 [rAsp f 3(15-168)], 1 to 142, and 15 to 142 and lacking the known bipartite sequence required for IgE binding, were also shown to be protective. Remarkably, vaccination with either rAsp f 3(1-142) or rAsp f 3(15-168) drastically diminished the production of antigen-specific antibodies compared to vaccination with the full-length rAsp f 3(1-168) or the double-truncated rAsp f 3(15-142) version. Our findings point to a possible mechanism in which Asp f 3 vaccination induces a cellular immune response that upon infection results in the activation of lymphocytes that in turn enhances and/or restores the function of corticosteroid-suppressed macrophages to clear fungal elements in the lungs.
Campylobacter jejuniColonization of Mice with Limited Enteric Flora
Authors: Chang Christopher , Miller Jeff F.
Published: August 2006

We have developed experimental murineCampylobacterinfection models which demonstrate efficient establishment and reproducible, high-level colonization. Following oral inoculation, wild-type C3H mice with normal enteric flora were colonized inconsistently and inefficiently byC. jejunistrain 81-176. However, C3H mice with a limited gut flora (LF) were efficiently colonized at high levels (108CFU/g of stool or large intestine tissue) followed by clearance after several weeks. Large intestine tissue showed minimal to mild inflammation at days 7 and 28 postinoculation. In striking contrast, C3H SCID mice with the same limited flora remained persistently colonized at a consistently high level until they were euthanized 8 months postinoculation. Lower gastrointestinal tract tissue from LF-SCID mice showed marked to severe inflammation in the colon and cecum at days 7 and 28 and intense inflammation of the stomach at day 28. These findings indicate that although the innate response alone cannot block colonization persistence, it is sufficient to orchestrate marked gut inflammation. Moreover, the adaptive immune response is critical to mediateC. jejuniclearance from the colonized gut. To validate our LF murine model, we verified that motility and chemotaxis are critical for colonization. Insertion-deletion mutations were generated inmotBandfliI, which encode products essential for motility and flagellar assembly, and in the presumptive chemotaxis genecheA(histidine kinase). All mutants failed to establish colonization in LF mice. Our limited flora murine colonization models serve as tractable, reproducible tools to define host responses toC. jejuniinfection and to identify and characterize virulence determinants required for colonization.
Mechanisms of Mortality in Early and Late Sepsis
Authors: Xiao Hongyan , Siddiqui Javed , Remick Daniel G.
Published: August 2006

A recent hypothesis postulates that sepsis moves through different phases, with periods of enhanced inflammation alternating with periods of immune suppression. In this study we determined the levels of inflammation present during early and late septic deaths to examine whether death was due to hyperinflammation or immunosuppression. The murine model of sepsis induced by cecal ligation and puncture (CLP) was used. Complete blood counts, plasma interleukin-6 (IL-6) levels, and body weights were determined. Mice that died within the first 4 days had increased plasma levels of IL-6, indicating that there was activation of the immune system. Cecal resection on day 4 after CLP resulted in decreased abscess size, lower circulating neutrophil counts, decreased anemia, and improved survival compared to the results for mice that received only antibiotic and fluid therapy. All of the mice that died in the chronic phase of infection (after day 4) had positive peritoneal cultures containing significantly more bacteria than the cultures for surviving mice. After day 4, none of the surviving mice exhibited increases in the plasma levels of IL-6. Dying mice exhibited mixed IL-6 responses; for 41% of the mice there was never an increase in the IL-6 levels in the chronic phase, while for other mice the levels of IL-6 transiently increased prior to death. Peritoneal macrophages were obtained in the late phase of sepsis from moribund and healthy mice and were stimulated ex vivo. The cells from the moribund mice produced significantly less IL-6 than the cells obtained from healthy mice produced. These results indicate that in mice that die in the early phase there is uniformly increased inflammation. However, during the chronic phase of sepsis, some mice die with evidence of immunosuppression (increased bacterial growth and low IL-6 levels), while other mice die with immunostimulation (high IL-6 levels and bacterial growth). Determining the inflammatory status of individual patients may help guide appropriate, targeted therapy.
Intestinal Intraepithelial Lymphocytes Sustain the Epithelial Barrier Function againstEimeria vermiformisInfection
Authors: Inagaki-Ohara Kyoko , Dewi Fitriya Nurannisa , Hisaeda Hajime , Smith Adrian L. , Jimi Fumiko , Miyahira Maki , Abdel-Aleem Ayman Samir Farid , Horii Yoichiro , Nawa Yukifumi
Published: August 2006

Eimeriaspp. are intracellular protozoa that infect intestinal epithelia of most vertebrates, causing coccidiosis. Intestinal intraepithelial lymphocytes (IEL) that reside at the basolateral site of epithelial cells (EC) have immunoregulatory and immunoprotective roles againstEimeriaspp. infection. However, it remains unknown how IEL are involved in the regulation of epithelial barrier duringEimeriasp. infection. Here, we demonstrated two distinct roles of IEL against infection withEimeria vermiformis, a murine pathogen: production of cytokines to induce protective immunity and expression of junctional molecules to preserve epithelial barrier. The number of IEL markedly increased when oocyst production reached a peak. During infection, IEL increased production of gamma interferon (IFN-γ) and tumor necrosis factor alpha (TNF-α) and decreased transforming growth factor β (TGF-β) production. Addition of IFN-γ and TNF-α or supernatants obtained from cultured IEL fromE. vermiformis-infected mice reduced transepithelial electrical resistance (TER) in a confluent CMT93 cell monolayer, a murine intestine-derived epithelial line, but antibodies against these cytokines suppressed the decline of TER. Moreover, TGF-β attenuated the damage of epithelial monolayer and changes in TER caused by IFN-γ and TNF-α. The expression of junctional molecules by EC was decreased when IEL produced a high level of IFN-γ and TNF-α and a low level of TGF-β inE. vermiformis-infected mice. Interestingly, IEL constantly expressed junctional molecules and a coculture of EC with IEL increased TER. These results suggest that IEL play important multifunctional roles not only in protection of the epithelium againstE. vermiformis-induced change by cytokine production but also in direct interaction with the epithelial barrier when intra-EC junctions are down-regulated.