bluuebunny/crossref_metadata_2025_split huggingface dataset:
Inhibition of Fungal β-1,3-Glucan Synthase and Cell Growth by HM-1 Killer Toxin Single-Chain Anti-Idiotypic Antibodies
Authors: Selvakumar Dakshnamurthy , Miyamoto Masahiko , Furuichi Yasuhiro , Komiyama Tadazumi 
Published: August 2006

ABSTRACTSingle-chain variable-fragment (scFv) anti-idiotypic antibodies of an HM-1 killer toxin (HM-1) from the yeastWilliopsis saturnusvar.mrakiiIFO 0895 have been produced by recombinant DNA technology from the splenic lymphocytes of mice immunized by idiotypic vaccination with a neutralizing monoclonal antibody (nMAb-KT). The fungicidal activity of scFv anti-idiotypic antibodies against the isolates of fourCandidaspecies was assessed by MIC analysis. scFv antibodies were fungicidal at concentrations of 1.56 to 12.5 μg/ml in vitro against fourCandidaspecies. The scFv antibodies exerted a strong candidacidal activity in vitro, with 50% inhibitory concentration (IC50) values ranging from 7.3 × 10−8to 16.0 × 10−8M, and were neutralized by adsorption with nMAb-KT. Furthermore, all scFv antibodies effectively inhibited fungal β-1,3-glucan synthase activity in vitro, with IC50values ranging from 2.0 × 10−8to 22.7 × 10−8M, values which almost coincide with the values that are inhibitory to the growth of fungal cells. Binding assays showed that the scFv antibodies specifically bind to nMAb-KT, and this binding pattern was confirmed by surface plasmon resonance analysis. The binding ability was further demonstrated by the competition observed between scFv antibodies and HM-1 to bind nMAb-KT. To the best of our knowledge, this is the first study to show that an antifungal anti-idiotypic antibody, in the form of recombinant scFv, potentially inhibits β-1,3-glucan synthase activity.
Metabolic Activation of Pradefovir by CYP3A4 and Its Potential as an Inhibitor or Inducer
Authors: Lin Chin-chung , Fang Che , Benetton Salete , Xu Gui-fen , Yeh Li-Tain 
Published: August 2006

ABSTRACTMetabolic activation of pradefovir to 9-(2-phosphonylmethoxyethyl)adenine (PMEA) was evaluated by using cDNA-expressed CYP isozymes in portal vein-cannulated rats following oral administration and in human liver microsomes. The enzyme induction potential of pradefovir was evaluated in rats following multiple oral dosing and in primary cultures of human hepatocytes. The results indicated that CYP3A4 is the only cDNA-expressed CYP isozyme catalyzing the conversion of pradefovir to PMEA. Pradefovir was converted to PMEA in human liver microsomes with aKmof 60 μM, a maximum rate of metabolism of 228 pmol/min/mg protein, and an intrinsic clearance of about 359 ml/min. Addition of ketoconazole and monoclonal antibody 3A4 significantly inhibits the conversion of pradefovir to PMEA in human liver microsomes, suggesting the predominant role of CYP3A4 in the metabolic activation of pradefovir. Pradefovir at 0.2, 2, and 20 μM was neither a direct inhibitor nor a mechanism-based inhibitor of CYP3A4, CYP2D6, CYP2C9, CYP2C19, CYP2E1, and CYP1A2 in human liver microsomes. In rats, the liver was the site of metabolic activation of pradefovir, whereas the small intestine did not play a significant role in the metabolic conversion of pradefovir to PMEA. Daily oral dosing (300 mg/kg of body weight) to rats for 8 days showed that pradefovir was not an inducer of P450 enzymes in rats. Furthermore, pradefovir at 10 μg/ml was not an inducer of either CYP1A2 or CYP3A4/5 in primary cultures of human hepatocytes.
In Silico Identification and Biological Evaluation of Antimicrobial Peptides Based on Human Cathelicidin LL-37
Authors: Sigurdardottir Thorgerdur , Andersson Pia , Davoudi Mina , Malmsten Martin , Schmidtchen Artur , Bodelsson Mikael 
Published: August 2006

ABSTRACT

Bacterial lipopolysaccharides (LPS) are important triggers of the widespread inflammatory response, which contributes to the development of multiple organ failure during sepsis. The helical 37-amino-acid-long human antimicrobial peptide LL-37 not only possesses a broad-spectrum antimicrobial activity but also binds and neutralizes LPS. However, the use of LL-37 in sepsis treatment is hampered by the fact that it is also cytotoxic. To find a less toxic analog of LL-37, we used in silico analysis to identify amphipathic helical regions of LL-37. A 21-amino-acid fragment (GKE) was synthesized, the biological actions of which were compared to those of two equally long peptides derived from the N and C termini of LL-37 as well as native LL-37. GKE displayed antimicrobial activity against
Escherichia coli
,
Pseudomonas aeruginosa
,
Staphylococcus aureus
,
Candida albicans
, and
Candida parapsilosis
that was similar to or even stronger than LL-37. GKE, as well as the equally long control peptides, attracted granulocytes in a fashion similar to that of LL-37, while only GKE was as potent as LL-37 in inhibiting LPS-induced vascular nitric oxide production. GKE caused less hemolysis and apoptosis in human cultured smooth muscle cells than LL-37. In summary, we have identified an active domain of LL-37, GKE, which displays antimicrobial activity in vitro and LPS-binding activity similar to those of LL-37 but is less toxic. GKE therefore holds promise as a template for the development of peptide antibiotics for the treatment of sepsis.
Efficacy and Pharmacokinetics of Bacteriophage Therapy in Treatment of Subclinical
Staphylococcus aureus
Mastitis in Lactating Dairy Cattle
Authors: Gill J. J. , Pacan J. C. , Carson M. E. , Leslie K. E. , Griffiths M. W. , Sabour P. M. 
Published: August 2006

ABSTRACT

Bovine mastitis is an inflammation of the udder caused by microbial infection. Mastitis caused by
Staphylococcus aureus
is a major concern to the dairy industry due to its resistance to antibiotic treatment and its propensity to recur chronically. Growing concerns surrounding antibiotic resistance have spurred research into alternative treatment methods. The ability of lytic
S. aureus
bacteriophage K to eliminate bovine
S. aureus
intramammary infection during lactation was evaluated in a placebo-controlled, multisite trial. Twenty-four lactating Holstein cows with preexisting subclinical
S. aureus
mastitis were treated. Treatment consisted of 10-ml intramammary infusions of either 1.25 × 10
11
PFU of phage K or saline, administered once per day for 5 days. The cure rate was established by the assessment of four serial samples collected following treatment. The cure rate was 3 of 18 quarters (16.7%) in the phage-treated group, while none of the 20 saline-treated quarters were cured. This difference was not statistically significant. The effects of phage intramammary infusion on the bovine mammary gland were also studied. In healthy lactating cows, a single infusion of either filter-sterilized broth lysate or a CsCl gradient-purified phage preparation elicited a large increase in the milk somatic cell count. This response was not observed when phage was infused into quarters which were already infected with
S. aureus
. Phage-infused healthy quarters continued to shed viable bacteriophage into the milk for up to 36 h postinfusion. The phage concentration in the milk suggested that there was significant degradation or inactivation of the infused phage within the gland.
Short-Term Administration of a Cell-Permeable Caveolin-1 Peptide Prevents the Development of Monocrotaline-Induced Pulmonary Hypertension and Right Ventricular Hypertrophy
Authors: Jasmin Jean-François , Mercier Isabelle , Dupuis Jocelyn , Tanowitz Herbert B. , Lisanti Michael P. 
Published: August 2006

Background—Caveolins (Cavs), the principal structural proteins of caveolar microdomains, have been implicated in the development of pulmonary hypertension (PH). Mice with homozygous deletion of the Cav-1 gene develop PH and right ventricular hypertrophy (RVH). Reductions in pulmonary Cav-1 expression have been shown in several animal models of PH and in patients with severe PH. Whether in vivo modulation of Cav-1 expression could affect the development of PH and RVH remains unknown. Therefore, we investigated the effect of in vivo administration of a Cav-1 mimetic peptide on the development of monocrotaline (MCT)-induced PH.Methods and Results—Thirty minutes after injection of saline or 60 mg/kg MCT, rats were assigned to receive a daily injection of saline, a peptide corresponding to the homeodomain of theDrosophilatranscription factorantennapedia(AP; 2.5 mg · kg−1· d−1), or a peptide consisting of the Cav-1–scaffolding domain coupled to AP (AP-Cav; 2.5 mg · kg−1· d−1) for 2 weeks. MCT and MCT+AP rats developed PH with respective right ventricular systolic pressures of 40.2±1.5 and 39.6±1.5 mm Hg. Administration of AP-Cav to MCT rats significantly reduced the right ventricular systolic pressure to 30.1±1.3 mm Hg. MCT and MCT+AP rats also developed pulmonary artery medial hypertrophy and RVH, which was normalized by administration of AP-Cav. Mechanistically, the development of PH was associated with reduced expression of pulmonary Cav-1 and Cav-2, hyperactivation of the STAT3 signaling cascade, and upregulation of cyclin D1 and D3 protein levels, all of which were prevented by administration of AP-Cav.Conclusions—Short-term administration of a Cav-based cell-permeable peptide to MCT rats prevents the development of pulmonary artery medial hypertrophy, PH, and RVH.
MAP-ping genomic organization and organ-specific expression profiles of poplar MAP kinases and MAP kinase kinases
Authors: Nicole Marie-Claude , Hamel Louis-Philippe , Morency Marie-Josée , Beaudoin Nathalie , Ellis Brian E , Séguin Armand 
Published: August 2006

Abstract

Background
As in other eukaryotes, plant mitogen-activated protein kinase (MAPK) cascades are composed of three classes of hierarchically organized protein kinases, namely MAPKKKs, MAPKKs, and MAPKs. These modules rapidly amplify and transduce extracellular signals into various appropriate intracellular responses. While extensive work has been conducted on the post-translational regulation of specific MAPKKs and MAPKs in various plant species, there has been no systematic investigation of the genomic organization and transcriptional regulation of these genes.

Results
Ten putative poplar MAPKK genes (PtMKKs) and 21 putative poplar MAPK genes (PtMPKs) have been identified and located within the poplar (Populus trichocarpa) genome. Analysis of exon-intron junctions and of intron phase inside the predicted coding region of each candidate gene has revealed high levels of conservation within and between phylogenetic groups. Expression profiles of all members of these two gene families were also analyzed in 17 different poplar organs, using gene-specific primers directed at the 3'-untranslated region of each candidate gene and real-time quantitative PCR. Most PtMKKs and PtMPKs were differentially expressed across this developmental series.

Conclusion
This analysis provides a complete survey of MAPKK and MAPK gene expression profiles in poplar, a large woody perennial plant, and thus complements the extensive expression profiling data available for the herbaceous annual Arabidopsis thaliana. The poplar genome is marked by extensive segmental and chromosomal duplications, and within both kinase families, some recently duplicated paralogous gene pairs often display markedly different patterns of expression, consistent with the rapid evolution of specialized protein functions in this highly adaptive species.
Optimization of a large-scale gene disruption protocol in Dictyostelium and analysis of conserved genes of unknown function
Authors: Torija Patricia , Robles Alicia , Escalante Ricardo 
Published: August 2006

Abstract

Background
Development of the post-genomic age in Dictyostelium will require the existence of rapid and reliable methods to disrupt genes that would allow the analysis of entire gene families and perhaps the possibility to undertake the complete knock-out analysis of all the protein-coding genes present in Dictyostelium genome.

Results
Here we present an optimized protocol based on the previously described construction of gene disruption vectors by in vitro transposition. Our method allows a rapid selection of the construct by a simple PCR approach and subsequent sequencing. Disruption constructs were amplified by PCR and the products were directly transformed in Dictyostelium cells. The selection of homologous recombination events was also performed by PCR. We have constructed 41 disruption vectors to target genes of unknown function, highly conserved between Dictyostelium and human, but absent from the genomes of S. cerevisiae and S. pombe. 28 genes were successfully disrupted.

Conclusion
This is the first step towards the understanding of the function of these conserved genes and exemplifies the easiness to undertake large-scale disruption analysis in Dictyostelium.
Heritability and major gene effects on left ventricular mass in the Chinese population: a family study
Authors: Chien Kuo-Liong , Hsu Hsiu-Ching , Su Ta-Chen , Chen Ming-Fong , Lee Yuan-Teh 
Published: August 2006

AbstractBackgroundGenetic components controlling for echocardiographically determined left ventricular (LV) mass are still unclear in the Chinese population.MethodsWe conducted a family study from the Chin-San community, Taiwan, and a total of 368 families, 1145 subjects, were recruited to undergo echocardiography to measure LV mass. Commingling analysis, familial correlation, and complex segregation analysis were applied to detect component distributions and the mode of inheritance.ResultsThe two-component distribution model was the best-fitting model to describe the distribution of LV mass. The highest familial correlation coefficients were mother-son (0.379,P< .0001) and father-son (0.356,P< .0001). Genetic heritability (h2) of LV mass was estimated as 0.268 ± 0.061 (P< .0001); it decreased to 0.153 ± 0.052 (P= .0009) after systolic blood pressure adjustment. Major gene effects with polygenic components were the best-fitting model to explain the inheritance mode of LV mass. The estimated allele frequency of the gene was 0.089.ConclusionThere were significant familial correlations, heritability and a major gene effect on LV mass in the population-based families.
Syndecan-1 mediates internalization of apoE-VLDL through a low density lipoprotein receptor-related protein (LRP)-independent, non-clathrin-mediated pathway
Authors: Wilsie Larissa C , Gonzales Amanda M , Orlando Robert A 
Published: August 2006

Abstract

Background
Triacylglyerol-rich very low density lipoprotein (VLDL) particles are the primary carriers of fatty acids in the circulation and as such serve as a rich energy source for peripheral tissues. Receptor-mediated uptake of these particles is dependent upon prior association with apolipoprotein E (apoE-VLDL) and is brought about by cell surface heparan sulfate proteoglycans (HSPG) in some cell types and by the low density lipoprotein receptor-related protein (LRP) in others. Although LRP's role in apoE-VLDL uptake has been well studied, the identity of the HSPG family member that mediates apoE-VLDL uptake has not been established. We investigated if syndecan-1 (Syn-1), a transmembrane cell surface HSPG, is able to mediate the internalization of apoE-VLDL and examined the relationship between Syn-1 and LRP toward apoE-VLDL uptake. For this study, we used a human fibroblast cell line (GM00701) that expresses large amounts of LRP, but possesses no LDL receptor activity to eliminate its contributions toward apoE-VLDL uptake.

Results
Although LRP in these cells is fully active as established by substantial α2macroglobulin binding and internalization, uptake of apoE-VLDL is absent. Expression of human Syn-1 cDNA restored apoE-VLDL binding and uptake by these cells. Competition for this uptake with an LRP ligand-binding antagonist had little or no effect, whereas co-incubation with heparin abolished apoE-VLDL internalization. Depleting Syn-1 expressing cells of K+, to block clathrin-mediated endocytosis, showed no inhibition of Syn-1 internalization of apoE-VLDL. By contrast, treatment of cells with nystatin to inhibit lipid raft function, prevented the uptake of apoE-VLDL by Syn-1.

Conclusion
These data demonstrate that Syn-1 is able to mediate apoE-VLDL uptake in human fibroblasts with little or no contribution from LRP and that the endocytic path taken by Syn-1 is clathrin-independent and relies upon lipid raft function. These data are consistent with previous studies demonstrating Syn-1 association with lipid raft domains.
Learning to perform a new movement with robotic assistance: comparison of haptic guidance and visual demonstration
Authors: Liu J , Cramer S C , Reinkensmeyer DJ 
Published: August 2006

AbstractBackgroundMechanical guidance with a robotic device is a candidate technique for teaching people desired movement patterns during motor rehabilitation, surgery, and sports training, but it is unclear how effective this approach is as compared to visual demonstration alone. Further, little is known about motor learning and retention involved with either robot-mediated mechanical guidance or visual demonstration alone.MethodsHealthy subjects (n = 20) attempted to reproduce a novel three-dimensional path after practicing it with mechanical guidance from a robot. Subjects viewed their arm as the robot guided it, so this "haptic guidance" training condition provided both somatosensory and visual input. Learning was compared to reproducing the movement following only visual observation of the robot moving along the path, with the hand in the lap (the "visual demonstration" training condition). Retention was assessed periodically by instructing the subjects to reproduce the path without robotic demonstration.ResultsSubjects improved in ability to reproduce the path following practice in the haptic guidance or visual demonstration training conditions, as evidenced by a 30–40% decrease in spatial error across 126 movement attempts in each condition. Performance gains were not significantly different between the two techniques, but there was a nearly significant trend for the visual demonstration condition to be better than the haptic guidance condition (p = 0.09). The 95% confidence interval of the mean difference between the techniques was at most 25% of the absolute error in the last cycle. When asked to reproduce the path repeatedly following either training condition, the subjects' performance degraded significantly over the course of a few trials. The tracing errors were not random, but instead were consistent with a systematic evolution toward another path, as if being drawn to an "attractor path".ConclusionThese results indicate that both forms of robotic demonstration can improve short-term performance of a novel desired path. The availability of both haptic and visual input during the haptic guidance condition did not significantly improve performance compared to visual input alone in the visual demonstration condition. Further, the motor system is inclined to repeat its previous mistakes following just a few movements without robotic demonstration, but these systematic errors can be reduced with periodic training.
Analysis of vaccinia virus temperature-sensitive I7L mutants reveals two potential functional domains
Authors: Moerdyk Megan J , Byrd Chelsea M , Hruby Dennis E 
Published: August 2006

Abstract
As an approach to initiating a structure-function analysis of the vaccinia virus I7L core protein proteinase, a collection of conditional-lethal mutants in which the mutation had been mapped to the I7L locus were subjected to genomic sequencing and phenotypic analyses. Mutations in six vaccinia virus I7L temperature sensitive mutants fall into two groups: changes at three positions at the N-terminal end between amino acids 29 and 37 and two different substitutions at amino acid 344, near the catalytic domain. Regardless of the position of the mutation, mutants at the non-permissive temperature failed to cleave core protein precursors and had their development arrested prior to core condensation. Thus it appears that the two clusters of mutations may affect two different functional domains required for proteinase activity.
Human nasal rhinosporidiosis: an Italian case report
Authors: Morelli Luca , Polce Mario , Piscioli Francesco , Del Nonno Franca , Covello Renato , Brenna Alessia , Cione Antonio , Licci Stefano 
Published: August 2006

AbstractBackgroundRhinosporidiosis is a disease affecting primarily the mucosa of nose, conjunctiva and urethra. It is endemic in some Asiatic regions, affecting people of any age and sex. Its manifestation is a polypoid mass growing inside the affected cavity and the only treatment is surgical excision.Rhinosporidium seeberiis the aetiological agent. Many discussions arouse regarding the taxonomic classification of the microorganism, recent studies established it is an aquatic protistan parasite. The lesion may recur and sometimes cause osteolytic bone lesions. In endemic areas it is not easy to establish if recurrent lesions are due to relapse or reinfection.Case presentationA 26-year-old male patient from India, resident in Italy since 2005, presented in March 2006 with a history of nasal obstruction of three months duration. Physical examination showed an erythematous, papillomatous mass, 3 cm in diameter, obstructing the right nasal cavity. A microscopic diagnosis of rhinosporidiosis was made. Few Italian human cases of this disease have been previously reported in the literature.ConclusionRhinosporidiosis is a condition which both clinicians and pathologists should keep in mind when managing patients from endemic countries with nasal masses. Moreover, it is very interesting in such cases to follow the clinical course: an eventual recurrence of the lesion in our patient would mean a true relapse, excluding the possibility of a reinfection, more probable in the endemic areas.
Redundant and unique regulation of activated mouse B lymphocytes by IL-4 and IL-21
Authors: Jin Haoli , Malek Thomas R 
Published: August 2006

Abstract
IL-21 distinctively regulates B cell growth and death, and it redundantly functions with IL-4 for IgG production. B cells likely encounter IL-4 and IL-21 in vivo, as both are secreted by activated T cells. Therefore, the action of both these cytokines was investigated during activation of B cells. IL-21 or the combination of IL-4 and IL-21 inhibited proliferation by purified mouse B cells to LPS or CpG DNA, whereas these cytokines enhanced proliferation after engaging the BCR or CD40. Although B cell subsets expressed somewhat varied levels of the IL-21 receptor, LPS-stimulated follicular and marginal B cell subsets were also dominantly susceptible to IL-21-induced growth arrest and cell death. After activation of B cells with CD40 and LPS, IL-4 and IL-21 distinctively regulated the expression of CD23, CD44, and CD138, and they cooperatively promoted IgG1 class-switching and synthesis. These findings support a model in which the presence of IL-4 and IL-21 inhibits B cells activated by polyclonal innate signals, and they promote B cell expansion and differentiation during T cell-dependent antibody responses, although the individual responses to IL-4 and IL-21 do not always overlap.