bluuebunny/crossref_metadata_2025_split huggingface dataset:
Pharmacological Inhibition of the ClpXP Protease Increases Bacterial Susceptibility to Host Cathelicidin Antimicrobial Peptides and Cell Envelope-Active Antibiotics
Authors: McGillivray Shauna M. , Tran Dan N. , Ramadoss Nitya S. , Alumasa John N. , Okumura Cheryl Y. , Sakoulas George , Vaughn Micah M. , Zhang Dawn X. , Keiler Kenneth C. , Nizet Victor 
Published: January 2012

ABSTRACT

The ClpXP protease is a critical bacterial intracellular protease that regulates protein turnover in many bacterial species. Here we identified a pharmacological inhibitor of the ClpXP protease, F2, and evaluated its action in
Bacillus anthracis
and
Staphylococcus aureus
. We found that F2 exhibited synergistic antimicrobial activity with cathelicidin antimicrobial peptides and antibiotics that target the cell well and/or cell membrane, such as penicillin and daptomycin, in
B. anthracis
and drug-resistant strains of
S. aureus
. ClpXP inhibition represents a novel therapeutic strategy to simultaneously sensitize pathogenic bacteria to host defenses and pharmaceutical antibiotics.
PXR
Variants and Artemisinin Use in Vietnamese Subjects: Frequency Distribution and Impact on the Interindividual Variability of CYP3A Induction by Artemisinin
Authors: Piedade Rita , Schaeffeler Elke , Winter Stefan , Asimus Sara , Schwab Matthias , Ashton Michael , Burk Oliver , Gil José P. 
Published: January 2012

ABSTRACT

Artemisinins induce drug metabolism through the activation of the pregnane X receptor (PXR)
in vitro
. Here, we report the resequencing and genotyping of
PXR
variants in 75 Vietnamese individuals previously characterized for CYP3A enzyme activity after artemisinin exposure. We identified a total of 31
PXR
variants, including 5 novel single nucleotide polymorphisms (SNPs), and we identified significantly different allele frequencies relative to other ethnic groups. A trend of significance was observed between the level of CYP3A4 induction by artemisinin and two
PXR
variants, the 8118C→T (Y328Y) and 10719A→G variants.
In Vitro
Antimicrobial Resistance of Urinary Escherichia coli Isolates among U.S. Outpatients from 2000 to 2010
Authors: Sanchez Guillermo V. , Master Ronald N. , Karlowsky James A. , Bordon Jose M. 
Published: January 2012

ABSTRACT

This study examines
in vitro
antimicrobial resistance data from
Escherichia coli
isolates obtained from urine samples of U.S. outpatients between 2000 and 2010 using The Surveillance Network (TSN). Antimicrobial susceptibility results (
n
= 12,253,679) showed the greatest increases in
E. coli
resistance from 2000 to 2010 for ciprofloxacin (3% to 17.1%) and trimethoprim-sulfamethoxazole (TMP-SMX) (17.9% to 24.2%), whereas nitrofurantoin (0.8% to 1.6%) and ceftriaxone (0.2% to 2.3%) showed minimal change. From 2000 to 2010, the antimicrobial resistance of urinary
E. coli
isolates to ciprofloxacin and TMP-SMX among outpatients increased substantially.
A Hybrid Multistage Protein Vaccine Induces Protective Immunity against Murine Malaria
Authors: Singh Balwan , Cabrera-Mora Monica , Jiang Jianlin , Moreno Alberto 
Published: January 2012

ABSTRACTWe have previously reported the design and expression of chimeric recombinant proteins as an effective platform to deliver malaria vaccines. The erythrocytic and exoerythrocytic protein chimeras described included autologous T helper epitopes genetically linked to defined B cell epitopes. Proof-of-principle studies using vaccine constructs based on thePlasmodium yoeliicircumsporozoite protein (CSP) andP. yoeliimerozoite surface protein-1 (MSP-1) showed encouraging results when tested individually in this mouse malaria model. To evaluate the potential synergistic or additive effect of combining these chimeric antigens, we constructed a synthetic gene encoding a hybrid protein that combined both polypeptides in a single immunogen. The multistage vaccine was expressed in soluble form inEscherichia coliat high yield. Here we report that the multistage protein induced robust immune responses to individual components, with no evidence of vaccine interference. Passive immunization using purified IgG from rabbits immunized with the hybrid protein conferred more robust protection against the experimental challenge withP. yoeliisporozoites than passive immunization with purified IgG from rabbits immunized with the individual proteins. High antibody titers and high frequencies of CD4+- and CD8+-specific cytokine-secreting T cells were elicited by vaccination. T cells were multifunctional and able to simultaneously produce interleukin-2 (IL-2), gamma interferon (IFN-γ), and tumor necrosis factor alpha (TNF-α). The mechanism of vaccine-induced protection involved neutralizing antibodies and effector CD4+T cells and resulted in the control of hyperparasitemia and protection against malarial anemia. These data support our strategy of using an array of autologous T helper epitopes to maximize the response to multistage malaria vaccines.
Adiaspiromycosis Causing Respiratory Failure and a Review of Human Infections Due to Emmonsia and Chrysosporium spp
Authors: Anstead Gregory M. , Sutton Deanna A. , Graybill John R. 
Published: January 2012

ABSTRACT

We report a case of a 27-year-old male who presented with respiratory distress that required mechanical ventilation. Transbronchial biopsy revealed adiaspores of the fungus
Emmonsia crescens
within granulomata, a condition known as adiaspiromycosis. The patient received amphotericin products and corticosteroids, followed by itraconazole, and made a full recovery.
Emmonsia crescens
is a saprobe with a wide distribution that is primarily a rodent pathogen. The clinical characteristics of the 20 cases of human pulmonary adiaspiromycosis reported since the last comprehensive case review in 1993 are described here, as well as other infections recently reported for the genus
Emmonsia
. Pulmonary adiaspiromycosis has been reported primarily in persons without underlying host factors and has a mild to severe course. It remains uncertain if the optimal management of severe pulmonary adiaspiromycosis is supportive or if should consist of antifungal treatment, corticosteroids, or a combination of the latter two. The classification of fungi currently in the genus
Emmonsia
has undergone considerable revision since their original description, including being grouped with the genus
Chrysosporium
at one time. Molecular genetics has clearly differentiated the genus
Emmonsia
from the
Chrysosporium
species. Nevertheless, there has been a persistent confusion in the literature regarding the clinical presentation of infection with fungi of these two genera; to clarify this matter, the reported cases of invasive
Chrysosporium
infections were reviewed. Invasive
Chrysosporium
infections typically occur in impaired hosts and can have a fatal course. Based on limited
in vitro
susceptibility data for
Chrysosporium zonatum
, amphotericin B is the most active drug, itraconazole susceptibility is strain-dependent, and fluconazole and 5-fluorocytosine are not active.
Evaluation of Adding a Second Marker To Overcome Staphylococcus aureus spa Typing Homoplasies
Authors: Basset P. , Nübel U. , Witte W. , Blanc D. S. 
Published: January 2012

ABSTRACT

The utility of sequencing a second highly variable locus in addition to the
spa
gene (e.g., double-locus sequence typing [DLST]) was investigated to overcome limitations of a
Staphylococcus aureus
single-locus typing method. Although adding a second locus seemed to increase discriminatory power, it was not sufficient to definitively infer evolutionary relationships within a single multilocus sequence type (ST-5).
Performance Assessment of a Novel Two-Step Multiple Displacement Amplification-PCR Assay for Detection of Mycobacterium tuberculosis Complex in Sputum Specimens
Authors: Wu Na , Zhang Yuanyuan , Fu Jun , Zhang Ruifen , Feng Lan , Hu Yongfei , Li Xiaoliang , Lu Na , Zhao Xiuqin , Pan Yuanlong , Li Jing , Zhu Baoli , Wan KangLin 
Published: January 2012

ABSTRACT
A novel two-step multiple displacement amplification-PCR (MDA-PCR) assay for tuberculosis detection in 200 sputum specimens was evaluated. The MDA-PCR assay indicated a significant increase in sensitivity and specificity compared with those of standard PCR alone.
Variation ofB1Gene and AF146527 Repeat Element Copy Numbers According to Toxoplasma gondii Strains Assessed Using Real-Time Quantitative PCR
Authors: Costa Jean-Marc , Bretagne Stéphane 
Published: January 2012

ABSTRACTUsing the multicopyB1gene and AF146527 element for the amplification ofToxoplasma gondiiDNA raises the issue of reliable quantification for clinical diagnosis. We applied relative quantification to reference strains using the single-copyP30gene as a reference. According to the parasite type, the copy numbers for theB1gene and AF146527 element were found to be 5 to 12 and 4 to 8 times lower than the previous estimations of 35 and 230 copies, respectively.
Nosocomial Clustering of NDM-1-Producing Klebsiella pneumoniae Sequence Type 340 Strains in Four Patients at a South Korean Tertiary Care Hospital
Authors: Kim Mi-Na , Yong Dongeun , An Dongheui , Chung Hae-Sun , Woo Jun Hee , Lee Kyungwon , Chong Yunsop 
Published: January 2012

ABSTRACT

In November 2010, NDM-1-producing
Klebsiella pneumoniae
(NDMKP) was identified for the first time in South Korea from four patients with no history of traveling abroad who stayed for 21 to 205 days in a tertiary care hospital. All were sequence type (ST) 340 and had nearly identical XbaI pulsed-field gel electrophoresis (PFGE) patterns. The
bla
NDM-1
-carrying plasmids were in the IncN group, with sizes ranging from 50 to 200 kb. These findings suggest that NDMKP had already been introduced into South Korea before this clustering was found.
Induction of Immunological Tolerance to Adenoviral Vectors by Using a Novel Dendritic Cell-Based Strategy
Authors: Kushwah Rahul , Oliver Jordan R. , Duan Rongqi , Zhang Li , Keshavjee Shaf , Hu Jim 
Published: January 2012

ABSTRACTThe success of helper-dependent adenoviral (HD-Ad) vector-mediated lung gene therapy is hampered by the host immune response, which limits pulmonary transgene expression following multiple rounds of vector readminstration. Here, we show that HD-Ad-mediated pulmonary gene expression is sustained even upon three rounds of readministration to immunodeficient mice, highlighting the need to suppress the adaptive immune response for sustained gene expression following vector readministration. Therefore, we devised a dendritic cell (DC)-based strategy for induction of immunological tolerance toward HD-Ad vectors. DCs derived in the presence of interleukin-10 (IL-10) are refractory to HD-Ad-induced maturation and instead facilitate generation of IL-10-producing Tr1 regulatory T cells which suppress HD-Ad-induced T cell proliferation. Delivery of HD-Ad-pulsed, IL-10-modified DCs to mice induces long-lasting immunological tolerance to HD-Ad vectors, whereby pulmonary DC maturation, the T cell response, and antibody response to HD-Ad vectors are suppressed even after three rounds of pulmonary HD-Ad readministration. Moreover, sustained transgene expression is also observed in the lungs of mice immunized with HD-Ad-pulsed, IL-10-modified DCs even after three rounds of pulmonary HD-Ad delivery. Taken together, these studies identify the use of DCs generated in the presence of IL-10 as a novel strategy to induce long-lasting immune tolerance to HD-Ad vectors.
Mapping of Chikungunya Virus Interactions with Host Proteins Identified nsP2 as a Highly Connected Viral Component
Authors: Bouraï Mehdi , Lucas-Hourani Marianne , Gad Hans Henrik , Drosten Christian , Jacob Yves , Tafforeau Lionel , Cassonnet Patricia , Jones Louis M. , Judith Delphine , Couderc Thérèse , Lecuit Marc , André Patrice , Kümmerer Beate Mareike , Lotteau Vincent , Desprès Philippe , Tangy Frédéric , Vidalain Pierre-Olivier 
Published: January 2012

ABSTRACT

Chikungunya virus (CHIKV) is a mosquito-transmitted alphavirus that has been responsible for an epidemic outbreak of unprecedented magnitude in recent years. Since then, significant efforts have been made to better understand the biology of this virus, but we still have poor knowledge of CHIKV interactions with host cell components at the molecular level. Here we describe the extensive use of high-throughput yeast two-hybrid (HT-Y2H) assays to characterize interactions between CHIKV and human proteins. A total of 22 high-confidence interactions, which essentially involved the viral nonstructural protein nsP2, were identified and further validated in protein complementation assay (PCA). These results were integrated to a larger network obtained by extensive mining of the literature for reports on alphavirus-host interactions. To investigate the role of cellular proteins interacting with nsP2, gene silencing experiments were performed in cells infected by a recombinant CHIKV expressing
Renilla
luciferase as a reporter. Collected data showed that heterogeneous nuclear ribonucleoprotein K (hnRNP-K) and ubiquilin 4 (UBQLN4) participate in CHIKV replication
in vitro
. In addition, we showed that CHIKV nsP2 induces a cellular shutoff, as previously reported for other Old World alphaviruses, and determined that among binding partners identified by yeast two-hybrid methods, the tetratricopeptide repeat protein 7B (TTC7B) plays a significant role in this activity. Altogether, this report provides the first interaction map between CHIKV and human proteins and describes new host cell proteins involved in the replication cycle of this virus.
A Novel Approach for the Rapid Mutagenesis and Directed Evolution of the Structural Genes of West Nile Virus
Authors: Lin Tsai-Yu , Dowd Kimberly A. , Manhart Carolyn J. , Nelson Steevenson , Whitehead Stephen S. , Pierson Theodore C. 
Published: January 2012

ABSTRACT

Molecular clone technology has proven to be a powerful tool for investigating the life cycle of flaviviruses, their interactions with the host, and vaccine development. Despite the demonstrated utility of existing molecular clone strategies, the feasibility of employing these existing approaches in large-scale mutagenesis studies is limited by the technical challenges of manipulating relatively large molecular clone plasmids that can be quite unstable when propagated in bacteria. We have developed a novel strategy that provides an extremely rapid approach for the introduction of mutations into the structural genes of West Nile virus (WNV). The backbone of this technology is a truncated form of the genome into which DNA fragments harboring the structural genes are ligated and transfected directly into mammalian cells, bypassing entirely the requirement for cloning in bacteria. The transfection of cells with this system results in the rapid release of WNV that achieves a high titer (∼10
7
infectious units/ml in 48 h). The suitability of this approach for large-scale mutagenesis efforts was established in two ways. First, we constructed and characterized a library of variants encoding single defined amino acid substitutions at the 92 residues of the “pr” portion of the precursor-to-membrane (prM) protein. Analysis of a subset of these variants identified a mutation that conferred resistance to neutralization by an envelope protein-specific antibody. Second, we employed this approach to accelerate the identification of mutations that allow escape from neutralizing antibodies. Populations of WNV encoding random changes in the E protein were produced in the presence of a potent monoclonal antibody, E16. Viruses resistant to neutralization were identified in a single passage. Together, we have developed a simple and rapid approach to produce infectious WNV that accelerates the process of manipulating the genome to study the structure and function of the structural genes of this important human pathogen.
Identification of a Specific Region in the E1 Fusion Protein Involved in Zinc Inhibition of Semliki Forest Virus Fusion
Authors: Liu Catherine Y. , Kielian Margaret 
Published: January 2012

ABSTRACT

The enveloped alphaviruses infect cells via a low-pH-triggered membrane fusion reaction mediated by the viral transmembrane protein E1. During fusion, E1 inserts into the target membrane and refolds to a hairpin-like postfusion conformation in which domain III (DIII) and the juxtamembrane stem pack against a central core trimer. Although zinc has previously been shown to cause a striking block in alphavirus fusion with liposome target membranes, the mechanism of zinc's effect on the E1 fusion protein is not understood. Here we developed a cell culture system to study zinc inhibition of fusion and infection of the alphavirus Semliki Forest virus (SFV). Inclusion of 2 mM ZnCl
2
in the pH 5.75 fusion buffer caused a decrease of ∼5 logs in SFV fusion at the plasma membrane. Fusion was also inhibited by nickel, a chemically related transition metal. Selection for SFV zinc resistance identified a key histidine residue, H333 on E1 DIII, while other conserved E1 histidine residues were not involved. An H333N mutation conferred resistance to both zinc and nickel, with properties in keeping with the known pH-dependent chelation of these metals by histidine. Biochemical studies demonstrated that zinc strongly inhibits formation of the postfusion E1 trimer in wild-type SFV but not in an H333 mutant. Together our results suggest that zinc acts by blocking the fold-back of DIII via its interaction with H333.
Stromal keratin expression in phyllodes tumours of the breast: a comparison with other spindle cell breast lesions
Authors: Chia Yifoong , Thike Aye Aye , Cheok Poh Yian , Yong-Zheng Chong Luke , Man-Kit Tse Gary , Tan Puay Hoon 
Published: January 2012

AimTo determine the frequency, pattern and distribution of stromal keratin expression in phyllodes tumours if any, which may impact diagnostic approaches.MethodsThe clinicopathological features of 109 phyllodes tumours comprising 70 (64.2%) benign, 30 (27.5%) borderline and nine (8.3%) malignant grades were evaluated, and the immunohistochemical expression of a keratin panel (MNF116, 34βE12, CK7, CK14, AE1/3, Cam5.2), p63 and CD34 in their stromal component was assessed.ResultsThere was focal and patchy cytoplasmic keratin staining in 1–5% of stromal cells in 13 (11.9%), 24 (22%), 31 (28.4%), 2 (1.8%), 9 (8.3%) and 2 (1.8%) cases for MNF116, 34βE12, CK7, CK14, AE1/3, Cam5.2, respectively. CD34 was expressed in 79 (72.5%) cases. There was no stromal staining for p63. Stromal MNF116, 34βE12 and Cam5.2 reactivity was significantly associated with phyllodes tumour grade (p=0.027, p=0.034, p=0.009 respectively), while MNF116 stromal staining was observed in tumours with increasing cellularity (p=0.036), necrosis (p=0.015) and cystic change (p=0.048). Contrary to common understanding, these findings confirm that stromal cells in phyllodes tumours can sometimes express keratins, albeit focal and in a patchy distribution. In comparison, fibromatosis and dermatofibrosarcoma were uniformly negative for the same keratin panel, while spindle cell components of eight metaplastic carcinomas expressed at least two or more keratins in a wider distribution of up to 90% of positively stained spindle cells. All eight spindle cell sarcomas were negative for keratins.ConclusionThe use of keratins as an adjunctive immunohistochemical diagnostic tool in the differential work-up of spindle cell tumours of the breast has to be interpreted with caution especially on limited core biopsy material.
Phosphorylated p120-catenin expression has predictive value for oral cancer progression
Authors: Ma Li-Wei , Zhou Zeng-Tong , He Qing-Bo , Jiang Wei-Wen 
Published: January 2012

AimsRecent studies have shown that phosphorylation of p120-catenin (p120) promotes progression and invasion of oral squamous cell carcinoma (OSCC) cells. The objective of the current study was to evaluate the usefulness of phosphorylated p120-catenin (pp120) as a biomarker for predicting clinical behaviour in the carcinogenesis of potentially malignant oral lesions.MethodsIn a retrospective follow-up study, the expression pattern of pp120 protein was determined using immunohistochemistry in samples from 68 patients with potentially malignant oral lesions, including patients with untransformed lesions (n=38) and patients with malignant transformed lesions (n=30). Analysis of corresponding post-malignant lesions (OSCCs) was also performed.ResultsThere was high expression of pp120 in 35 of 68 (51.5%) of general potentially malignant oral lesions and 23 of 30 (76.7%) of OSCCs compared with expression in normal oral mucosa. Kaplan–Meier analysis revealed that patients with potentially malignant oral lesions expressing high levels of membranous pp120 had a significantly higher incidence of OSCC than those expressing low expressing pp120 (p=0.002; log-rank test). Cox regression analysis revealed that this pp120 expression pattern was significantly associated with a 3.43-fold increase in the risk of malignant progression (p=0.007). In addition, there was a significant correlation between high levels of membranous expression of pp120 in pre-malignant lesions and cytoplasmic expression in post-malignant lesions (p=0.028).ConclusionsThe data indicated that a high level of membranous expression of pp120 in potentially malignant oral lesions is an early event during oral carcinogenesis, and that the mislocalisation of expression of pp120 from the cell membrane to the cytoplasm is associated with oral cancer progression. pp120 may serve as a useful marker for the identification of a high risk of potentially malignant oral lesions progressing to OSCC.
ASSESSMENT SYSTEM FOR FEASIBILITY ANALYSIS OF NATIONAL R&D PROGRAMS: THE CASE OF KOREA
Authors: LEE YOON BEEN , PARK JIYOUNG 
Published: January 2012

Most assessments for R&D programs are conducted for on-going or finished programs. In order to streamline national R&D programs, Korean government is making a challenging attempt. It enacted a law for ex ante evaluation for national R&D programs and KISTEP, which specializes in evaluation and planning for R&D programs, took charge of the important role. KISTEP created and developed guidelines for feasibility analysis on each category of R&D program. Many kinds of R&D programs, such as constructing facilities for nuclear fusion and developing IT components by organizing consortiums, were analyzed from the viewpoint of technology experts and policy makers. Various impacts expected to be made by R&D programs were crucial elements for the analysis too. This paper presents processes for the feasibility analysis of R&D programs, cruces of the processes, and how we have improved the assessment system. It also provides how the assessment system contributed to the innovation of national R&D programs.