bluuebunny/crossref_metadata_2025_split huggingface dataset:
Differentially Expressed and Secreted Major Immunoreactive Protein Orthologs of
Ehrlichia canis
and
E. chaffeensis
Elicit Early Antibody Responses to Epitopes on Glycosylated Tandem Repeats
Authors: Doyle C. Kuyler , Nethery Kimberly A. , Popov Vsevolod L. , McBride Jere W. 
Published: December 2005

ABSTRACT

Ehrlichia canis
major immunoreactive proteins of 36 and 19 kDa elicit the earliest detectable antibody responses during the acute phase of canine monocytic ehrlichiosis. Genes encoding the major immunoreactive 36-kDa protein of
E. canis
and the corresponding ortholog of
E. chaffeensis
(47 kDa) were identified and the proteins characterized. The molecular masses of the strongly immunoreactive recombinant proteins were larger than predicted (26.7 and 32.9 kDa, respectively) but were consistent with those of the corresponding native proteins (36 and 47 kDa). Similar to other reported ehrlichial immunoreactive glycoproteins, carbohydrate was detected on the recombinant expressed proteins, indicating that they were glycoproteins. Both glycoproteins (gp36 and gp47) have carboxy-terminal serine/threonine-rich tandem repeat regions containing repeats that vary in number (4 to 16 repeats) and amino acid sequence among different isolates of each species.
E. canis
gp36 was recognized by early acute-phase antibodies (day 14), and species-specific antibody epitopes were mapped to C-terminal nonhomologous repeat units of gp36 and gp47. Periodate treatment of recombinant gp36 reduced the antibody reactivity, and nonglycosylated synthetic peptide repeat units from
E. canis
gp36 and
E. chaffeensis
gp47 were substantially less immunoreactive than corresponding recombinant peptides, demonstrating that glycans are important epitope determinants that are structurally conserved on the recombinant proteins expressed in
Escherichia coli. E. canis
gp36 and
E. chaffeensis
gp47 were differentially expressed only on the surface of dense-cored ehrlichiae and detected in the
Ehrlichia
-free supernatants, indicating that these proteins are released extracellularly during infection.
Inhibition of Macrophage Apoptosis by
Neisseria meningitidis
Requires Nitric Oxide Detoxification Mechanisms
Authors: Tunbridge Anne J. , Stevanin Tania M. , Lee Margaret , Marriott Helen M. , Moir James W. B. , Read Robert C. , Dockrell David H. 
Published: December 2005

ABSTRACT

Host-driven macrophage apoptosis contributes to innate immunity during bacterial infection.
Neisseria meningitidis
inhibits apoptosis in a variety of cells, but its impact on macrophage apoptosis is unknown. We demonstrate that
N. meningitidis
prevents macrophage apoptosis via genes encoding nitric oxide detoxification and a porin, PorB.
Contribution of Sialic Acid-Binding Adhesin to Pathogenesis of Experimental Endocarditis Caused by
Streptococcus gordonii
DL1
Authors: Takahashi Yukihiro , Takashima Eizo , Shimazu Kisaki , Yagishita Hisao , Aoba Takaaki , Konishi Kiyoshi 
Published: December 2005

ABSTRACT

An insertional mutation in
hsa
, the gene encoding the sialic acid-binding adhesin of
Streptococcus gordonii
DL1, resulted in a significant reduction of the infection rate of the organism and an inflammatory reaction in the rat aortic valve with experimental endocarditis, suggesting that the adhesin contributes to the infectivity of the organism for heart valves.
The
pap
Operon of Avian Pathogenic
Escherichia coli
Strain O1:K1 Is Located on a Novel Pathogenicity Island
Authors: Kariyawasam Subhashinie , Johnson Timothy J. , Nolan Lisa K. 
Published: December 2005

ABSTRACT

We have identified a 56-kb pathogenicity island (PAI) in avian pathogenic
Escherichia coli
strain O1:K1 (APEC-O1). This PAI, termed PAI I
APEC-O1
, is integrated adjacent to the 3′ end of the
pheV
tRNA gene. It carries putative virulence genes of APEC (
pap
operon), other
E. coli
genes (
tia
and
ireA
), and a 1.5-kb region unique to APEC-O1. The
kps
gene cluster required for the biosynthesis of polysialic acid capsule was mapped to a location immediately downstream of this PAI.
Listeria monocytogenes10403S HtrA Is Necessary for Resistance to Cellular Stress and Virulence
Authors: Wilson Rebecca L. , Brown Lindsay L. , Kirkwood-Watts Dana , Warren Travis K. , Lund S. Amanda , King David S. , Jones Kevin F. , Hruby Dennis E. 
Published: December 2005

ABSTRACTThe HtrA serine protease has been shown to be essential for bacterial virulence and for survival after exposure to many types of environmental and cellular stresses. AListeria monocytogenes10403ShtrAmutant was found to be sensitive to oxidative and puromycin-induced stress at high temperatures, showed a reduced ability to form biofilms, and was attenuated for virulence in mice.
Adoptive Immunotherapy against Experimental Visceral Leishmaniasis with CD8+T Cells Requires the Presence of Cognate Antigen
Authors: Polley Rosalind , Stager Simona , Prickett Sara , Maroof Asher , Zubairi Soombul , Smith Deborah F. , Kaye Paul M. 
Published: December 2005

ABSTRACTCD8+T cells have a protective role in experimental visceral leishmaniasis. However, the observation that inflammatory cytokines induce bystander activation of CD8+T cells questions the need for antigen-dependent effector function. Here, we demonstrate that successful adoptive immunotherapy with CD8+T cells is strictly dependent upon the presence of cognate antigen.
A PE Protein Expressed by
Mycobacterium avium
Is an Effective T-Cell Immunogen
Authors: Parra Marcela , Cadieux Nathalie , Pickett Thames , Dheenadhayalan Veerabadran , Brennan Michael J. 
Published: December 2005

ABSTRACT

Infection of mice with
Mycobacterium avium
or immunization with a novel PE gene expressed by
M. avium
(MaPE) showed that a dominant T-cell immune response was elicited. Immunization with an MaPE DNA vaccine protected mice against an aerosol challenge with
Mycobacterium tuberculosis
, suggesting that mycobacteria express PE antigens with cross-protective T-cell epitopes.
New World Monkey
Aotus nancymae
as a Model for
Campylobacter jejuni
Infection and Immunity
Authors: Jones Franca R. , Baqar Shahida , Gozalo Alfonso , Nunez Gladys , Espinoza Nereyda , Reyes Sharina M. , Salazar Milagros , Meza Rina , Porter Chad K. , Walz Stephen E. 
Published: December 2005

ABSTRACT

Three groups of six monkeys (
Aotus nancymae
) each were inoculated intragastrically with increasing doses of
Campylobacter jejuni
. Infection resulted in fecal colonization (100% of monkeys), dose-related diarrhea, and robust immune responses. Colonization duration and diarrhea rate were reduced upon secondary challenge.
A. nancymae
may be useful for studying anti-
Campylobacter
vaccine efficacy.
Correlation between Lethal Toxin-Neutralizing Antibody Titers and Protection from Intranasal Challenge with
Bacillus anthracis
Ames Strain Spores in Mice after Transcutaneous Immunization with Recombinant Anthrax Protective Antigen
Authors: Peachman Kristina K. , Rao Mangala , Alving Carl R. , Burge Robert , Leppla Stephen H. , Rao Venigalla B. , Matyas Gary R. 
Published: December 2005

ABSTRACT

Transcutaneous immunization of mice with recombinant protective antigen (rPA) of
Bacillus anthracis
resulted in significantly higher lethal toxin-neutralizing antibody titers than did intramuscular injection of alum-adsorbed rPA. Immunized mice were partially protected against intranasal challenge with 235,000 (10 50% lethal doses) Ames strain
B. anthracis
spores. A highly significant correlation was observed between toxin-neutralizing antibody titer and survival after challenge. Future experiments with rabbits and nonhuman primates should confirm the significance of protection by this vaccine strategy.
Natural Human Antibody Responses to
Plasmodium vivax
Apical Membrane Antigen 1 under Low Transmission and Unstable Malaria Conditions in Sri Lanka
Authors: Wickramarachchi Thilan , Premaratne Prasad H. , Perera K. L. R. Lakshman , Bandara Sumith , Kocken Clemens H. M. , Thomas Alan W. , Handunnetti Shiroma M. , Udagama-Randeniya Preethi V. 
Published: December 2005

ABSTRACT

Plasmodium vivax
apical membrane antigen 1, an important malaria vaccine candidate, was immunogenic during natural malaria infections in Sri Lanka, where low transmission and unstable malaria conditions prevail. Antibody prevalence increased with exposure in areas where malaria was or was not endemic. A marked isotype switch to cytophilic (immunoglobulin G1 [IgG1]/IgG3) antibodies was evident with increasing exposure exclusively in residents from areas of endemicity.
Caspase and Bid Involvement inClostridium difficileToxin A-Induced Apoptosis and Modulation of Toxin A Effects by Glutamine and Alanyl-Glutamine In Vivo and In Vitro
Authors: Carneiro Benedito A. , Fujii Jun , Brito Gerly A. C. , Alcantara Cirle , Oriá Reinaldo B. , Lima Aldo A. M. , Obrig Tom , Guerrant Richard L. 
Published: December 2005

ABSTRACTClostridium difficileis the leading cause of nosocomial bacterial diarrhea. Glutamine and its stable and highly soluble derivative alanyl-glutamine, have been beneficial in models of intestinal injury. In this study, we extend our work on the mechanisms ofClostridium difficiletoxin A (TxA)-induced apoptosis in human intestinal epithelial T84 cells and evaluate the effects of glutamine and alanyl-glutamine on TxA-induced apoptosis in vitro and disruption of ileal mucosa in vivo. T84 cells were incubated with TxA (100 ng/ml) in medium with or without glutamine or alanyl-glutamine (3 to 100 mM). Apoptosis was evaluated by DNA fragmentation in vitro and the terminal deoxynucleotidyltransferase-mediated dUTP-biotin nick end-labeling method in vivo. Caspase and Bid involvement were investigated by Western blotting. Ligated rabbit ileal loops were used for the evaluation of intestinal secretion, mucosal disruption, and apoptosis. TxA induced caspases 6, 8, and 9 prior to caspase 3 activation in T84 cells and induced Bid cleavage by a caspase-independent mechanism. Glutamine or alanyl-glutamine significantly reduced TxA-induced apoptosis of T84 cells by 47% and inhibited activation of caspase 8. Both glutamine and alanyl-glutamine reduced TxA-induced ileal mucosal disruption and secretion. Altogether, we further delineated the apoptosis-signaling cascade induced by TxA in T84 cells and demonstrated the protective effects of glutamine and alanyl-glutamine. Glutamine and alanyl-glutamine inhibited the apoptosis of T84 cells by preventing caspase 8 activation and reduced TxA-induced intestinal secretion and disruption.
Dissection of ESAT-6 System 1 of
Mycobacterium tuberculosis
and Impact on Immunogenicity and Virulence
Authors: Brodin Priscille , Majlessi Laleh , Marsollier Laurent , de Jonge Marien I. , Bottai Daria , Demangel Caroline , Hinds Jason , Neyrolles Olivier , Butcher Philip D. , Leclerc Claude , Cole Stewart T. , Brosch Roland 
Published: December 2005

ABSTRACT

The dedicated secretion system ESX-1 of
Mycobacterium tuberculosis
encoded by the extended RD1 region (extRD1) assures export of the ESAT-6 protein and its partner, the 10-kDa culture filtrate protein CFP-10, and is missing from the vaccine strains
M. bovis
BCG and
M. microti
. Here, we systematically investigated the involvement of each individual ESX-1 gene in the secretion of both antigens, specific immunogenicity, and virulence. ESX-1-complemented BCG and
M. microti
strains were more efficiently engulfed by bone-marrow-derived macrophages than controls, and this may account for the enhanced in vivo growth of ESX-1-carrying strains. Inactivation of gene
pe35
(Rv3872) impaired expression of CFP-10 and ESAT-6, suggesting a role in regulation. Genes Rv3868, Rv3869, Rv3870, Rv3871, and Rv3877 encoding an ATP-dependent chaperone and translocon were essential for secretion of ESAT-6 and CFP-10 in contrast to
ppe68
Rv3873 and Rv3876, whose inactivation did not impair secretion of ESAT-6. A strict correlation was found between ESAT-6 export and the generation of ESAT-6 specific T-cell responses in mice. Furthermore, ESAT-6 secretion and specific immunogenicity were almost always correlated with enhanced virulence in the SCID mouse model. Only loss of Rv3865 and part of Rv3866 did not affect ESAT-6 secretion or immunogenicity but led to attenuation. This suggests that Rv3865/66 represent a new virulence factor that is independent from ESAT-6 secretion. The present study has allowed us to identify new aspects of the extRD1 region of
M. tuberculosis
and to explore its role in the pathogenesis of tuberculosis.
Interaction of
Cryptosporidium hominis
and
Cryptosporidium parvum
with Primary Human and Bovine Intestinal Cells
Authors: Hashim Amna , Mulcahy Grace , Bourke Billy , Clyne Marguerite 
Published: December 2005

ABSTRACT

Cryptosporidiosis in humans is caused by the zoonotic pathogen
Cryptosporidium parvum
and the anthroponotic pathogen
Cryptosporidium hominis
. To what extent the recently recognized
C. hominis
species differs from
C. parvum
is unknown. In this study we compared the mechanisms of
C. parvum
and
C. hominis
invasion using a primary cell model of infection. Cultured primary bovine and human epithelial intestinal cells were infected with
C. parvum
or
C. hominis
. The effects of the carbohydrate lectin galactose-
N
-acetylgalactosamine (Gal/GalNAc) and inhibitors of cytoskeletal function and signal transduction mechanisms on entry of the parasites into host cells were tested. HCT-8 cells (human ileocecal adenocarcinoma cells) were used for the purpose of comparison. Pretreatment of parasites with Gal/GalNAc inhibited entry of
C. parvum
into HCT-8 cells and primary bovine cells but had no effect on entry of either
C. parvum
or
C. hominis
into primary human cells or on entry of
C. hominis
into HCT-8 cells. Both
Cryptosporidium
species entered primary cells by a protein kinase C (PKC)- and actin-dependent mechanism. Staurosporine, in particular, attenuated infection, likely through a combination of PKC inhibition and induction of apoptosis. Diversity in the mechanisms used by
Cryptosporidium
species to infect cells of different origins has important implications for understanding the relevance of in vitro studies of
Cryptosporidium
pathogenesis.
Where Should the Femoral Tunnel of a Posterior Cruciate Ligament Reconstruction be Placed to Best Restore Anteroposterior Laxity and Ligament Forces?
Authors: Markolf Keith L. , Feeley Brian T. , Jackson Steven R. , McAllister David R. 
Published: December 2005

Background Objective results of posterior cruciate ligament reconstruction are often less than satisfactory, with many patients exhibiting excessive posterior laxity. Hypothesis Changes in the position of the femoral tunnel within the posterior cruciate ligament's femoral footprint will significantly affect anteroposterior laxities and graft forces. Study Design Controlled laboratory study. Methods The posterior cruciate ligament's femoral origin was mechanically isolated in 13 fresh-frozen knee specimens, and the bone cap containing the ligament's insertion was attached to a load cell that recorded resultant force during tibial loading tests. Anteroposterior laxity (at ± 200 N applied force) was also measured. Cast acrylic replicas of the bone cap were fabricated, with tunnels placed in anterolateral, central, and posteromedial regions of the footprint. A graft reconstruction was tested in each tunnel. Results Mean laxities with the anterolateral tunnel were + 0.9 mm to + 1.7 mm greater than normal between 0 ° and 45 ° of flexion. Mean laxities with the posteromedial tunnel were –2.4 mm to –3.7 mm less than normal between 10 ° and 45 ° of flexion. Mean laxities with the central tunnel were not significantly different from intact knee values, except at 0 ° (0.9 mm greater). Mean graft forces with the anterolateral tunnel were normal for most modes of loading, whereas there were significant increases in graft forces with the posteromedial and central tunnels. Conclusion The anterolateral tunnel reproduced normal posterior cruciate ligament force profiles but produced a knee that was more lax than normal between 0 ° and 45 ° of flexion. The central tunnel best matched intact knee laxities, but graft forces were higher than posterior cruciate ligament forces between 0 ° and 45 ° of flexion. The posteromedial tunnel overconstrained anteroposterior laxity approximately 2 to 4 mm between 0 ° and 45 ° of flexion and generated higher graft forces in the same flexion range. Clinical Relevance This study suggests that a posteromedial tunnel should not be used for single-bundle posterior cruciate ligament reconstruction.
Anterior Cruciate Ligament Revision Reconstruction
Authors: Noyes Frank R. , Barber-Westin Sue D. 
Published: December 2005

Background The quadriceps tendon is a viable graft source for revision anterior cruciate ligament reconstruction. Purpose To determine the functional results and graft failure rates in knees in which the patellar tendon had been previously harvested or was unavailable, expanded tunnels precluded the use of a semitendinosus-gracilis graft, or patients requested autogenous tissues instead of allografts for revision reconstruction. Study Design Case series; Level of evidence, 4. Methods The authors observed 21 patients for a mean of 49 months postoperatively after revision anterior cruciate ligament reconstruction with a quadriceps tendon graft. The results were determined by KT-2000 arthrometer testing, the Cincinnati Knee Rating System, and the International Knee Documentation Committee Rating System. Fifteen knees required a concurrent procedure, including reconstruction of posterolateral structures in 5 knees, meniscal repairs in 5 knees, and high tibial osteotomy in 2 knees. Results Significant improvements occurred in symptoms (P< .0001), daily activities (P< .05), sports activities (P< .01), and the overall rating scores (P< .0001). Eighteen patients rated their knee condition as improved. Total mean anterior-posterior displacements decreased from 8.4 ± 3.1 mm preoperatively to 2.0 ± 2.3 mm at follow-up (P< .001). On the International Knee Documentation Committee knee ligament rating, 17 knees were graded as normal or nearly normal, 3 were graded as abnormal, and 1 was graded as severely abnormal. Conclusion The revision operation provided reasonable results in this group of complex knees. However, the functional and overall results were inferior to those reported for primary anterior cruciate ligament reconstruction. Many knees (90%) had compounding problems of articular cartilage damage, meniscectomy, varus malalignment, or additional ligamentous injury that most likely affected the results.
Arthroscopic Treatment of Posterolateral Elbow Impingement from Lateral Synovial Plicae in Throwing Athletes and Golfers
Authors: Kim David H. , Gambardella Ralph A. , Elattrache Neal S. , Yocum Lewis A. , Jobe Frank W. 
Published: December 2005

Background Although elbow pain is common in throwing athletes and golfers, posterolateral impingement from a hypertrophic synovial plica is a rare but possibly underdiagnosed condition. Purpose To evaluate the clinical results of arthroscopic treatment of symptomatic lateral elbow plicae in this athletic population. Study Design Case series; Level of evidence, 4. Methods Twelve patients, 9 male and 3 female, whose mean age was 21.6 years (range, 17-33 years), were reviewed. There were 7 baseball pitchers, 2 softball players, and 3 golfers. All patients had diagnosed isolated lateral elbow plica; none had lateral epicondylitis, instability, osteochondritis dissecans, arthritis, loose bodies, or nerve conditions. The mean time from onset of symptoms to treatment was 9.25 months (range, 3-24.5 months). At a mean follow-up of 33.8 months (range, 24-65.5 months), patients were evaluated with a questionnaire and examination, based on the American Shoulder and Elbow Surgeons standardized elbow assessment and previously reported elbow outcome score. Results Posterolateral elbow pain was present in all patients. Fifty-eight percent (7 of 12 patients) complained of clicking or catching, whereas only 25% (3 of 12) experienced swelling or effusion. At elbow arthroscopy, a thickened synovial lateral plica was debrided in all cases. Ninety-two percent (11 of 12 patients) reported an excellent outcome with a mean elbow score of 92.5 points (maximum, 100 points). Return to competitive play averaged 4.8 months (range, 3-9.5 months). One patient with a fair outcome developed medial elbow instability that later required reconstructive surgery. Conclusion Posterolateral elbow impingement from hypertrophic synovial plicae can cause significant pain and disability in throwing athletes and golfers. With careful diagnosis and exclusion of other elbow problems, treatment with arthroscopic debridement and focused rehabilitation is highly successful and allows these athletes to return to their previous level of play.
Pathophysiological classification of chronic rhinosinusitis
Authors: Baraniuk James N , Maibach Hilda 
Published: December 2005

Abstract

Background
Recent consensus statements demonstrate the breadth of the chronic rhinosinusitis (CRS) differential diagnosis. However, the classification and mechanisms of different CRS phenotypes remains problematic.

Method
Statistical patterns of subjective and objective findings were assessed by retrospective chart review.

Results
CRS patients were readily divided into those with (50/99) and without (49/99) polyposis. Aspirin sensitivity was limited to 17/50 polyp subjects. They had peripheral blood eosinophilia and small airways obstruction. Allergy skin tests were positive in 71% of the remaining polyp subjects. IgE was<10 IU/ml in 8/38 polyp and 20/45 nonpolyp subjects (p = 0.015, Fisher's Exact test). CT scans of the CRS without polyp group showed sinus mucosal thickening (probable glandular hypertrophy) in 28/49, and nasal osteomeatal disease in 21/49. Immunoglobulin isotype deficiencies were more prevalent in nonpolyp than polyp subjects (p < 0.05).

Conclusion
CRS subjects were retrospectively classified in to 4 categories using the algorithm of (1) polyp vs. nonpolyp disease, (2) aspirin sensitivity in polyposis, and (3) sinus mucosal thickening vs. nasal osteomeatal disease (CT scan extent of disease) for nonpolypoid subjects. We propose that the pathogenic mechanisms responsible for polyposis, aspirin sensitivity, humoral immunodeficiency, glandular hypertrophy, eosinophilia and atopy are primary mechanisms underlying these CRS phenotypes. The influence of microbial disease and other factors remain to be examined in this framework. We predict that future clinical studies and treatment decisions will be more logical when these interactive disease mechanisms are used to stratify CRS patients.