bluuebunny/crossref_metadata_2025 huggingface dataset:
TiCN coatings deposited by large area filtered arc deposition technique
Authors: Cheng Y. H. , Browne T. , Heckerman B.
Published: March 2010

Nanocrystalline TiCN coatings were deposited from Ti targets under the atmosphere of mixed N2 and CH4 gases using a novel large area filtered arc deposition technique at a temperature of 350 °C. The microstructure, crystalline structure, bonding structure, coating composition, hardness, modulus, plasticity, and adhesion of the deposited TiCN coatings were systematically characterized using optical microscopy, x-ray diffraction (XRD), x-ray photoelectron spectroscopy, nanoindentation, Rockwell adhesion test, and scratch adhesion test, respectively. By adding 5% CH4 gas into the chamber, only 2.31 at. % of C was incorporated into the TiN coating to form Ti–C bonds. However, XRD results show a drastic change in the preferred orientation of the TiN grains from strong (111) to strong (220) orientation, as well as a decrease in grain size. Nanoindentation tests indicate a significant increase in hardness and elastic modulus. The plasticity and toughness of the TiCN coatings are comparable to that of the TiN coatings. Adhesion tests show that the TiCN coatings possess excellent adhesion on both 316 and 440a stainless steel substrates.
“Spontaneous” Release Trigger
Authors: Hurtley Stella M.
Published: March 2010

Spontaneous synaptic vesicle fusion is triggered by soluble proteins that compete with synaptotagmins to induce membrane curvature.
When a Channel Is Not a Channel
Authors: Gough Nancy R.
Published: March 2010

In fish, the calcium channel required for excitation-contraction coupling does not conduct calcium.
Heart Cell Signaling in 3D
Authors: Kiberstis Paula A.
Published: March 2010

A change in the distribution of a signaling molecule on the surface of heart muscle cells may contribute to heart failure.
TWEAKing Muscle Atrophy
Authors: Adler Elizabeth M.
Published: March 2010

Denervation makes muscles more responsive to the muscle-wasting cytokine TWEAK.
Toothsome Signaling Parameters
Authors: Ray L. Bryan
Published: March 2010

Simple changes in signaling mechanisms can explain variation in tooth morphology in a wild population of seals.
Lipid Kinase Revealed
Authors: Vinson Valda
Published: March 2010

Structural data might provide a foundation to develop specific inhibitors to a class of phosphoinositide 3-kinases.
The Role of the Kinases RIP1 and RIP3 in TNF-Induced Necrosis
Authors: Vandenabeele Peter , Declercq Wim , Van Herreweghe Franky , Vanden Berghe Tom
Published: March 2010

Programmed necrosis in response to TNF requires the activity of two serine-threonine kinases.
ramR
Mutations in Clinical Isolates of
Klebsiella pneumoniae
with Reduced Susceptibility to Tigecycline
Authors: Hentschke M. , Wolters M. , Sobottka I. , Rohde H. , Aepfelbacher M.
Published: March 2010

Five
Klebsiella pneumoniae
isolates with reduced susceptibility to tigecycline (MIC, 2 μg/ml) were analyzed. A gene homologous to
ramR
of
Salmonella enterica
was identified in
Klebsiella pneumoniae
. Sequencing of
ramR
in the nonsusceptible
Klebsiella
strains revealed deletions, insertions, and point mutations. Transformation of mutants with wild-type
ramR
genes, but not with mutant
ramR
genes, restored susceptibility to tigecycline and repressed overexpression of
ramA
and
acrB
. Thus, this study reveals a molecular mechanism for tigecycline resistance in
Klebsiella pneumoniae
.
Role ofpfmdr1Amplification and Expression in Induction of Resistance to Artemisinin Derivatives inPlasmodium falciparum
Authors: Chavchich Marina , Gerena Lucia , Peters Jennifer , Chen Nanhua , Cheng Qin , Kyle Dennis E.
Published: March 2010

Artemisinin and its derivatives are the most rapidly acting and efficacious antimalarial drugs currently available. Although resistance to these drugs has not been documented, there is growing concern about the potential for resistance to develop. In this paper we report the selection of parasite resistance to artelinic acid (AL) and artemisinin (QHS)in vitroand the molecular changes that occurred during the selection. Exposure of threePlasmodium falciparumlines (W2, D6, and TM91C235) to AL resulted in decreases in parasite susceptibilities to AL and QHS, as well as to mefloquine, quinine, halofantrine, and lumefantrine. The changes in parasite susceptibility were accompanied by increases in the copy number, mRNA expression, and protein expression of thepfmdr1gene in the resistant progenies of W2 and TM91C235 parasites but not in those of D6 parasites. No changes were detected in the coding sequences of thepfmdr1,pfcrt,pfatp6,pftctp, andpfubcthgenes or in the expression levels ofpfatp6andpftctp. Our data demonstrate thatP. falciparumlines have the capacity to develop resistance to artemisinin derivativesin vitroand that this resistance is achieved by multiple mechanisms, to include amplification and increased expression ofpfmdr1, a mechanism that also confers resistance to mefloquine. This observation is of practical importance, because artemisinin drugs are often used in combination with mefloquine for the treatment of malaria.
Safety and Pharmacokinetics of Single Intravenous Dose of MGAWN1, a Novel Monoclonal Antibody to West Nile Virus
Authors: Beigel John H. , Nordstrom Jeffrey L. , Pillemer Stanley R. , Roncal Cory , Goldwater D. Ronald , Li Hua , Holland P. Chris , Johnson Syd , Stein Kathryn , Koenig Scott
Published: March 2010

West Nile Virus (WNV) is a neurotropic flavivirus that can cause debilitating diseases, such as encephalitis, meningitis, or flaccid paralysis. We report the safety, pharmacokinetics, and immunogenicity of a recombinant humanized monoclonal antibody (MGAWN1) targeting the E protein of WNV in a phase 1 study, the first to be performed on humans. A single intravenous infusion of saline or of MGAWN1 at escalating doses (0.3, 1, 3, 10, or 30 mg/kg of body weight) was administered to 40 healthy volunteers (30 receiving MGAWN1; 10 receiving placebo). Subjects were evaluated on days 0, 1, 3, 7, 14, 21, 28, 42, 56, 91, 120, and 180 by clinical assessments, clinical laboratory studies, electrocardiograms (ECGs), and pharmacokinetic and immunogenicity assays. All 40 subjects tolerated the infusion of the study drug, and 39 subjects completed the study. One serious adverse event of schizophrenia occurred in the 0.3-mg/kg cohort. One grade 3 neutropenia occurred in the 3-mg/kg cohort. Six MGAWN1-treated subjects experienced 11 drug-related adverse events, including diarrhea (1 subject), chest discomfort (1), oral herpes (1), rhinitis (1), neutropenia (2), leukopenia (1), dizziness (1), headache (2), and somnolence (1). In the 30-mg/kg cohort, MGAWN1 had a half-life of 26.7 days and a maximum concentration in serum (
C
max
) of 953 μg/ml. This study suggests that single infusions of MGAWN1 up to 30 mg/kg appear to be safe and well tolerated in healthy subjects. The
C
max
of 953 μg/ml exceeds the target level in serum estimated from hamster studies by 28-fold and should provide excess WNV neutralizing activity and penetration into the brain and cerebrospinal fluid (CSF). Further evaluation of MGAWN1 for the treatment of West Nile virus infections is warranted.
Effect of Vicriviroc on the QT/Corrected QT Interval and Central Nervous System in Healthy Subjects
Authors: O'Mara Edward , Kasserra Claudia , Huddlestone John Robert , Wan Yuntao , Soni Peter , Caceres Maria , Medlock Matthew , Morrison Royce , Devinsky Orrin
Published: March 2010

Vicriviroc is a CCR5 antagonist in clinical development for the treatment of HIV-1. Two phase I studies were conducted to assess the safety of vicriviroc. One study characterized the drug's potential to prolong the QT/corrected QT (QTc) interval and to induce arrhythmia. In this partially blind, parallel-group study, 200 healthy subjects aged 18 to 50 years were randomized in equal groups to the following regimens: (i) placebo for 9 days and a single dose of moxifloxacin at 400 mg on day 10, (ii) placebo, (iii) vicriviroc-ritonavir (30 and 100 mg), (iv) vicriviroc-ritonavir (150 and 100 mg), and (v) ritonavir (100 mg). The second study characterized the effects of a range of vicriviroc doses on the central nervous system (CNS). In this third-party-blind, parallel-group study, 30 healthy subjects aged 18 to 48 years were randomized to receive a single dose of either vicriviroc at 200, 250, or 300 mg or placebo, followed by multiple (seven) once-daily doses of either vicriviroc at 150, 200, or 250 mg or placebo, respectively. In the first study, vicriviroc produced no clinically meaningful effect on the QT/QTc interval when administered at a supratherapeutic or therapeutic dose concurrently with ritonavir. In the second study, vicriviroc produced no observable seizure activity, nor was it held to be associated with any clinically relevant changes in brain waveforms in the final consensus of reviewers. These findings showed that vicriviroc produced no clinically relevant QTc prolongation cardiac or epileptogenic effects in healthy individuals at exposures as high as five times those expected for HIV-infected patients receiving therapeutic doses of vicriviroc in a ritonavir-boosted protease inhibitor-containing regimen.
Preclinical Evaluation of the Antifolate QN254, 5-Chloro-N′6′-(2,5-Dimethoxy-Benzyl)-Quinazoline-2,4,6-Triamine, as an Antimalarial Drug Candidate
Authors: Nzila Alexis , Rottmann Matthias , Chitnumsub Penchit , Kiara Stevens M. , Kamchonwongpaisan Sumalee , Maneeruttanarungroj Cherdsak , Taweechai Supannee , Yeung Bryan K. S. , Goh Anne , Lakshminarayana Suresh B. , Zou Bin , Wong Josephine , Ma Ngai Ling , Weaver Margaret , Keller Thomas H. , Dartois Veronique , Wittlin Sergio , Brun Reto , Yuthavong Yongyuth , Diagana Thierry T.
Published: March 2010

Drug resistance against dihydrofolate reductase (DHFR) inhibitors—such as pyrimethamine (PM)—has now spread to almost all regions where malaria is endemic, rendering antifolate-based malaria treatments highly ineffective. We have previously shown that the di-amino quinazoline QN254 [5-chloro-N′6′-(2,5-dimethoxy-benzyl)-quinazoline-2,4,6-triamine] is active against the highly PM-resistantPlasmodium falciparumV1S strain, suggesting that QN254 could be used to treat malaria in regions with a high prevalence of antifolate resistance. Here, we further demonstrate that QN254 is highly active againstPlasmodium falciparumclinical isolates, displaying various levels of antifolate drug resistance, and we provide biochemical and structural evidence that QN254 binds and inhibits the function of both the wild-type and the quadruple-mutant (V1S) forms of the DHFR enzyme. In addition, we have assessed QN254 oral bioavailability, efficacy, and safetyin vivo. The compound displays favorable pharmacokinetic properties after oral administration in rodents. The drug was remarkably efficacious againstPlasmodium bergheiand could fully cure infected mice with three daily oral doses of 30 mg/kg. In the course of these efficacy studies, we have uncovered some dose limiting toxicity at higher doses that was confirmed in rats. Thus, despite its relativein vitroselectivity toward thePlasmodiumDHFR enzyme, QN254 does not show the adequate therapeutic index to justify its further development as a single agent.
Molecular Epidemiology, Sequence Types, and Plasmid Analyses of KPC-Producing
Klebsiella pneumoniae
Strains in Israel
Authors: Leavitt Azita , Carmeli Yehuda , Chmelnitsky Inna , Goren Moran G. , Ofek Itzhak , Navon-Venezia Shiri
Published: March 2010

Sporadic isolates of carbapenem-resistant KPC-2-producing
Klebsiella pneumoniae
were isolated in Tel Aviv Medical Center during 2005 and 2006, parallel to the emergence of the KPC-3-producing
K. pneumoniae
sequence type 258 (ST 258). We aimed to study the molecular epidemiology of these isolates and to characterize their
bla
KPC
-carrying plasmids and their origin. Ten isolates (8 KPC-2 and 2 KPC-3 producing) were studied. All isolates were extremely drug resistant. They possessed the
bla
KPC
gene and varied in their additional beta-lactamase contents. The KPC-2-producing strains belonged to three different sequence types: ST 340 (
n
= 2), ST 277 (
n
= 2), and a novel sequence type, ST 376 (
n
= 4). Among KPC-3-producing strains, a single isolate (ST 327) different from ST 258 was identified, but both strains carried the same plasmid (pKpQIL). The KPC-2-encoding plasmids varied in size (45 to 95 kb) and differed among each of the STs. Two of the
Klebsiella bla
KPC-2
-carrying plasmids were identical to plasmids from
Escherichia coli
, suggesting a common origin of these plasmids. These data indicate that KPC evolution in
K. pneumoniae
is related to rare events of interspecies spread of
bla
KPC-2
-carrying plasmids from
E. coli
followed by limited clonal spread, whereas KPC-3 carriage in this species is related almost strictly to clonal expansion of ST 258 carrying pKpQIL.
Mitogen-Activated Protein Kinase Phosphatase 2 Regulates the Inflammatory Response in Sepsis
Authors: Cornell Timothy T. , Rodenhouse Paul , Cai Qing , Sun Lei , Shanley Thomas P.
Published: March 2010

Sepsis results from a dysregulation of the regulatory mechanisms of the pro- and anti-inflammatory response to invading pathogens. The mitogen-activated protein (MAP) kinase cascades are key signal transduction pathways involved in the cellular production of cytokines. The dual-specific phosphatase 1 (DUSP 1), mitogen-activated protein kinase phosphatase-1 (MKP-1), has been shown to be an important negative regulator of the inflammatory response by regulating the p38 and Jun N-terminal protein kinase (JNK) MAP kinase pathways to influence pro- and anti-inflammatory cytokine production. MKP-2, also a dual-specific phosphatase (DUSP 4), is a phosphatase highly homologous with MKP-1 and is known to regulate MAP kinase signaling; however, its role in regulating the inflammatory response is not known. We hypothesized a regulatory role for MKP-2 in the setting of sepsis. Mice lacking the MKP-2 gene had a survival advantage over wild-type mice when challenged with intraperitoneal lipopolysaccharide (LPS) or a polymicrobial infection via cecal ligation and puncture. The MKP-2
−/−
mice also exhibited decreased serum levels of both pro-inflammatory cytokines (tumor necrosis factor alpha [TNF-α], interleukin-1β [IL-1β], IL-6) and anti-inflammatory cytokines (IL-10) following endotoxin challenge. Isolated bone marrow-derived macrophages (BMDMs) from MKP-2
−/−
mice showed increased phosphorylation of the extracellular signal-regulated kinase (ERK), decreased phosphorylation of JNK and p38, and increased induction of MKP-1 following LPS stimulation. The capacity for cytokine production increased in MKP-2
−/−
BMDMs following MKP-1 knockdown. These data support a mechanism by which MKP-2 targets ERK deactivation, thereby decreasing MKP-1 and thus removing the negative inhibition of MKP-1 on cytokine production.
Genome-Wide Transposon Mutagenesis Reveals a Role for pO157 Genes in Biofilm Development in
Escherichia coli
O157:H7 EDL933
Authors: Puttamreddy Supraja , Cornick Nancy A. , Minion F. Chris
Published: March 2010

Enterohemorrhagic
Escherichia coli
O157:H7, a world-wide human food-borne pathogen, causes mild to severe diarrhea, hemorrhagic colitis, and hemolytic uremic syndrome. The ability of this pathogen to persist in the environment contributes to its dissemination to a wide range of foods and food processing surfaces. Biofilms are thought to be involved in persistence, but the process of biofilm formation is complex and poorly understood in
E. coli
O157:H7. To better understand the genetics of this process, a mini-Tn
5
transposon insertion library was constructed in strain EDL933 and screened for biofilm-negative mutants using a microtiter plate assay. Ninety-five of 11,000 independent insertions (0.86%) were biofilm negative, and transposon insertions were located in 51 distinct genes/intergenic regions that must be involved either directly or indirectly in biofilm formation. All of the 51 biofilm-negative mutants showed reduced biofilm formation on both hydrophilic and hydrophobic surfaces. Thirty-six genes were unique to this study, including genes on the virulence plasmid pO157. The type V secreted autotransporter serine protease EspP and the enterohemolysin translocator EhxD were found to be directly involved in biofilm formation. In addition, EhxD and EspP were also important for adherence to T84 intestinal epithelial cells, suggesting a role for these genes in tissue interactions
in vivo
.
Cooperation between Multiple Microbial Pattern Recognition Systems Is Important for Host Protection against the Intracellular PathogenLegionella pneumophila
Authors: Archer Kristina A. , Ader Florence , Kobayashi Koichi S. , Flavell Richard A. , Roy Craig R.
Published: March 2010

Multiple pattern recognition systems have been shown to initiate innate immune responses to microbial pathogens. The degree to which these detection systems cooperate with each other to provide host protection is unknown. Here, we investigated the importance of several immune surveillance pathways in protecting mice against lethal infection by the intracellular pathogenLegionella pneumophila, the causative agent of a severe pneumonia called Legionnaires' disease. Rip2 and Naip5/NLRC4 signaling was found to contribute to the innate immune response generated againstL. pneumophilain the lung. Elimination of Rip2 or Naip5/NLRC4 signaling in MyD88-deficient mice resulted in increased replication and dissemination ofL. pneumophilaand higher rates of mortality. Irradiated wild-type mice receiving bone marrow cells from pattern recognition receptor-deficient mice displayedL. pneumophilainfection phenotypes similar to those of donor mice. Rip2 and Naip5/NLRC4 signaling provided additive effects in protecting MyD88-deficient mice from lethal infection byL. pneumophila, with the contribution of Naip5/NLRC4 being slightly greater than that of Rip2. Thus, activation of the Rip2, MyD88, and Naip5/NLRC4 signaling pathways triggers a coordinated and synergistic response that protects the host against lethal infection byL. pneumophila. These data provide new insight into how different pattern recognition systems interact functionally to generate innate immune responses that protect the host from lethal infection by activating cellular pathways that restrict intracellular replication ofL. pneumophilaand by recruiting to the site of infection additional phagocytes that eliminate extracellular bacteria.
Global Transcriptional Response of Macrophage-Like THP-1 Cells to Shiga Toxin Type 1
Authors: Leyva-Illades Dinorah , Cherla Rama P. , Galindo Cristi L. , Chopra Ashok K. , Tesh Vernon L.
Published: March 2010

Shiga toxins (Stxs) are bacterial cytotoxins produced by the enteric pathogensShigella dysenteriaeserotype 1 and some serotypes ofEscherichia colithat cause bacillary dysentery and hemorrhagic colitis, respectively. To date, approaches to studying the capacity of Stxs to alter gene expression in intoxicated cells have been limited to individual genes. However, it is known that many of the signaling pathways activated by Stxs regulate the expression of multiple genes in mammalian cells. To expand the scope of analysis of gene expression and to better understand the underlying mechanisms for the various effects of Stxs on host cell functions, we carried out comparative microarray analyses to characterize the global transcriptional response of human macrophage-like THP-1 cells to Shiga toxin type 1 (Stx1) and lipopolysaccharides. The data were analyzed by using a rigorous combinatorial approach with three separate statistical algorithms. A total of 36 genes met the criteria of upregulated expression in response to Stx1 treatment, with 14 genes uniquely upregulated by Stx1. Microarray data were validated by real-time reverse transcriptase PCR for genes encoding early growth response 1 (Egr-1) (transcriptional regulator), cyclooxygenase 2 (COX-2; inflammation), and dual specificity phosphatase 1 (DUSP1), DUSP5, and DUSP10 (regulation of mitogen-activated protein kinase signaling). Stx1-mediated signaling through extracellular signal-regulated kinase 1/2 and Egr-1 appears to be involved in the increased expression and production of the proinflammatory mediator tumor necrosis factor alpha. Activation of COX-2 is associated with the increased production of proinflammatory and vasoactive eicosanoids. However, the capacity of Stx1 to increase the expression of genes encoding phosphatases suggests that mechanisms to dampen the macrophage proinflammatory response may be built into host response to the toxins.
α-Galactosylceramide Promotes Killing ofListeria monocytogeneswithin the Macrophage Phagosome through Invariant NKT-Cell Activation
Authors: Emoto Masashi , Yoshida Tomomi , Fukuda Toshio , Kawamura Ikuo , Mitsuyama Masao , Kita Eiji , Hurwitz Robert , Kaufmann Stefan H. E. , Emoto Yoshiko
Published: March 2010

α-Galactosylceramide (α-GalCer) has been exploited for the treatment of microbial infections. Although amelioration of infection by α-GalCer involves invariant natural killer T (iNKT)-cell activation, it remains to be determined whether macrophages (Mφ) participate in the control of microbial pathogens. In the present study, we examined the participation of Mφ in immune intervention in infection by α-GalCer using a murine model of listeriosis. Phagocytic and bactericidal activities of peritoneal Mφ from C57BL/6 mice, but not iNKT cell-deficient mice, were enhanced after intraperitoneal injection of α-GalCer despite the absence of iNKT cells in the peritoneal cavity. High levels of gamma interferon (IFN-γ) and nitric oxide (NO) were detected in the peritoneal cavities of mice treated with α-GalCer and in culture supernatants of peritoneal Mφ from mice treated with α-GalCer, respectively. Although enhanced bactericidal activity of peritoneal Mφ by α-GalCer was abrogated by endogenous IFN-γ neutralization, this was only marginally affected by NO inhibition. Similar results were obtained by using a listeriolysin O-deficient strain ofListeria monocytogenes. Moreover, respiratory burst in Mφ was increased after α-GalCer treatment. Our results suggest that amelioration of listeriosis by α-GalCer is, in part, caused by enhanced killing ofL. monocytogeneswithin phagosomes of Mφ activated by IFN-γ from iNKT cells residing in an organ(s) other than the peritoneal cavity.
Biological Characterization ofChlamydia trachomatisPlasticity Zone MACPF Domain Family Protein CT153
Authors: Taylor Lacey D. , Nelson David E. , Dorward David W. , Whitmire William M. , Caldwell Harlan D.
Published: March 2010

Chlamydia trachomatisstrains are obligate intracellular human pathogens that share near genomic synteny but have distinct infection and disease organotropisms. The genetic basis for differences in the pathogen-host relationship among chlamydial strains is linked to a variable region of chlamydial genomes, termed the plasticity zone (PZ). Two groups of PZ-encoded proteins, the membrane attack complex/perforin (MACPF) domain protein (CT153) and members of the phospholipase D-like (PLD) family, are related to proteins that modify membranes and lipids, but the functions of CT153 and the PZ PLDs (pzPLDs) are unknown. Here, we show that full-length CT153 (p91) was present in the elementary bodies (EBs) of 15C. trachomatisreference strains. CT153 underwent a rapid infection-dependent proteolytic cleavage into polypeptides of 57 and 41 kDa that was independent ofde novochlamydial protein synthesis. Following productive infection, p91 was expressed during the mid-developmental cycle and was similarly processed into p57 and p41 fragments. Infected-cell fractionation studies showed that insoluble fractions contained p91, p57, and p41, whereas only p91 was found in the soluble fraction, indicating that unprocessed CT153 may be secreted. Finally, CT153 localized to a distinct population of reticulate bodies, some of which were in contact with the inclusion membrane.
Chlamydia pneumoniae
Infection in Polarized Epithelial Cell Lines
Authors: Törmäkangas Liisa , Markkula Eveliina , Lounatmaa Kari , Puolakkainen Mirja
Published: March 2010

We set up a polarized cell culture model to study the pathogenicity of a common respiratory tract pathogen,
Chlamydia pneumoniae
. Immunofluorescence staining of ZO-1 (a tight junction protein) and Na
+
K
+
ATPase (a protein pump localized at the basolateral membrane in the polarized epithelial cells), as well as TER measurements, suggested that the filter-grown Calu-3 cells, but not the A549 cells, were polarized when grown on collagen-coated membranes. Both the flat and the filter-grown cultures were infected with
C. pneumoniae
. Infection in the polarized Calu-3 cultures produced more
C. pneumoniae
genome equivalents than infection in the flat cultures. However, this progeny was not as infective as that in the flat cultures. The maximum amount of
C. pneumoniae
was detected at 6 days postinfection in the filter-grown A549 cells, indicating a slower developmental cycle than that observed in the flat A549 cultures. The effect of cycloheximide on the growth of
C. pneumoniae
in the polarized cells was negligible. Furthermore, the infection in the polarized Calu-3 cells was resistant to doxycycline, and several cytokines were released mainly on the apical side of the polarized cells in response to
C. pneumoniae
infection. These findings indicate that the growth of chlamydiae was altered in the filter-grown epithelial culture system. The diminished production of infective progeny of
C. pneumoniae
, together with the resistance to doxycycline and polarized secretion of cytokines from the infected Calu-3 cells, suggests that this model is useful for examining epithelial cell responses to
C. pneumoniae
infection, and it might better resemble
in vivo
infection in respiratory epithelial cells.
New Automated Hepatitis C Virus (HCV) Core Antigen Assay as an Alternative to Real-Time PCR for HCV RNA Quantification
Authors: Park Yongjung , Lee Jong-Han , Kim Beom Seok , Kim Do Young , Han Kwang-Hyub , Kim Hyon-Suk
Published: March 2010

An automated hepatitis C virus (HCV) antigen (Ag) assay was evaluated with clinical samples. Determination of HCV Ag and RNA levels in 282 subjects using Abbott HCV Ag and Roche Cobas
Taq
Man assays revealed that these two tests were highly correlated (
r
= 0.9464). Thus, the HCV Ag assay could be an alternative test to quantitative reverse transcription-PCR.
High Prevalence of Dihydropteroate Synthase Mutations in
Pneumocystis jirovecii
Isolated from Patients with
Pneumocystis
Pneumonia in South Africa
Authors: Dini Leigh , du Plessis Mignon , Frean John , Fernandez Victor
Published: March 2010

Pneumocystis jirovecii
pneumonia (PCP) is an important cause of morbidity and mortality in immunocompromised patients. Sulfa-containing drugs are used for the treatment and prophylaxis of PCP. Mutations in the
P. jirovecii fas
gene, which encodes dihydropteroate synthase (DHPS), are associated with prior exposure to sulfa drugs, and their appearance suggests the emergence of variants with reduced sulfa susceptibility. The present study examined the prevalence of DHPS mutations in
P. jirovecii
strains isolated from South African patients with PCP.
P. jirovecii
infection was investigated by immunofluorescence microscopy and quantitative real-time PCR with respiratory specimens from 712 patients (93% of whom were >15 years of age) with suspected PCP consecutively received for the detection of
P. jirovecii
over 1 year. PCR amplification and sequencing of the DHPS
fas
gene was attempted with DNA from the
P. jirovecii
-positive samples.
P. jirovecii
infection was confirmed by immunofluorescence microscopy in 168/712 (24%) of the patients. Carriage of the fungus was revealed by real-time PCR in 17% of the patients with negative microscopy results. The
P. jirovecii fas
gene was successfully amplified from specimens from 151 patients and sequenced. Mutations resulting in the Thr55Ala and/or Pro57Ser amino acid substitution were detected in
P. jirovecii
strains from 85/151 (56%) patients. The high frequency of PCP episodes with
P. jirovecii
harboring DHPS mutations in South Africa indicates that populations of this fungus are evolving under the considerable selective pressure exerted by sulfa-containing antibiotics. These results, similar to previous observations of sulfa drug resistance in bacterial populations, underscore the importance of the rational use of sulfa medications either prophylactically against PCP or for the treatment of other infections.
Improved Detection of Lassa Virus by Reverse Transcription-PCR Targeting the 5′ Region of S RNA
Authors: Ölschläger Stephan , Lelke Michaela , Emmerich Petra , Panning Marcus , Drosten Christian , Hass Meike , Asogun Danny , Ehichioya Deborah , Omilabu Sunday , Günther Stephan
Published: March 2010

The method of choice for the detection of Lassa virus is reverse transcription (RT)-PCR. However, the high degree of genetic variability of the virus poses a problem with the design of RT-PCR assays that will reliably detect all strains. Recently, we encountered difficulties in detecting some strains from Liberia and Nigeria in a commonly used glycoprotein precursor (GPC) gene-specific RT-PCR assay (A. H. Demby, J. Chamberlain, D. W. Brown, and C. S. Clegg, J. Clin. Microbiol. 32:2898-2903, 1994), which prompted us to revise the protocol. The design of the new assay, the GPC RT-PCR/2007 assay, took into account 62 S RNA sequences from all countries where Lassa fever is endemic, including 40 sequences generated from the strains in our collection. The analytical sensitivity of the new assay was determined with 11 strains from Sierra Leone, Liberia, Ivory Coast, and Nigeria by probit analysis; the viral loads detectable with a probability of 95% ranged from 342 to 2,560 S RNA copies/ml serum, which corresponds to 4 to 30 S RNA copies/assay. The GPC RT-PCR/2007 assay was validated with 77 serum samples and 1 cerebrospinal fluid sample from patients with laboratory-confirmed Lassa fever. The samples mainly originated from Liberia and Nigeria and included strains difficult to detect in the assay of 1994. The GPC RT-PCR/2007 assay detected virus in all clinical specimens (100% sensitivity). In conclusion, a new RT-PCR assay, based in part on the protocol developed by Demby et al. in 1994, for the detection of Lassa virus is described. Compared to the assay developed in 1994, the GPC RT-PCR/2007 assay offers improved sensitivity for the detection of Liberian and Nigerian Lassa virus strains.
Short-Term Effect of Acupuncture on Intraocular Pressure in Healthy Subjects
Authors: Meira-Freitas Daniel , Cariello Angelino Julio , Vita Ruth Cardoso , Tabosa Ângela , Melo Luiz Alberto S
Published: March 2010

Purpose

To evaluate the short-term effect of acupuncture on the intraocular pressure (IOP) in healthy subjects.

Methods

A randomised controlled double-blinded trial was performed. 48 healthy volunteers (94 eyes) were randomly allocated to three groups: acupuncture group—19 subjects (38 eyes) were submitted to a 20 min session of acupuncture (GB1, GB14 and BL1); sham group—14 subjects (27 eyes) were submitted to a 20 min session of acupuncture with needles inserted in false points; and control group—15 subjects (29 eyes) who underwent no intervention. All subjects had the IOP measured by a masked investigator using Goldmann applanation tonometry immediately before intervention, as well as 20 min and 24 h after.

Results

The mean (SD) IOP in the acupuncture group was 17.9 (3.3) mm Hg at baseline, 16.4 (3.9) mm Hg at 20 min and 16.3 (3.3) mm Hg at 24 h. The mean (SD) IOP in the sham group was 18.6 (3.3) mm Hg at baseline, 17.7 (2.6) mm Hg at 20 min and 15.9 (3.6) mm Hg at 24 h. The mean (SD) IOP in the control group was 16.9 (3.5) mm Hg at baseline, 16.5 (3.8) mm Hg at 20 min and 15.8 (3.3) mm Hg at 24 h. There was no statistically significant difference in the IOP variation (post-intervention minus baseline measurements) between groups after 20 min (p=0.13) and 24 h (p=0.21).

Conclusion

Acupuncture in the studied points did not produce significant short-term effect on the IOP of healthy individuals in comparison with control groups. Clinical Trials Registration Number: NCT00639977
Electroacupuncture Therapy for Arthralgia and Raynaud's Phenomenon in a Patient with Systemic Lupus Erythematosus
Authors: Donoyama Nozomi , Ohkoshi Norio
Published: March 2010

A 45-year-old woman with systemic lupus erythematosus presented with multiple arthralgia, coldness in fingers and toes, and Raynaud's phenomenon. Electroacupuncture (EA) therapy was performed in two courses (14 treatment sessions) 1 month apart. A needle was inserted in the proximal (or medial) side of the painful joint and another needle was inserted in the distal (or lateral) side of the same joint and a 50 Hz stimulus was applied (3 s bursts with 1 s gaps) for 15 min. A visual analogue scale was used to evaluate pain intensity. Cold provocation testing was conducted before and after EA sessions to determine the vasomotor response.

Visual analogue scale scores were lower after EA sessions than before. Before starting EA, the skin temperature of the right mid fingertip was 27.9°C and that of the left mid fingertip was 28.3°C. In contrast, after the EA sessions, the skin temperature of the right mid fingertip was 34.8°C and that of the left mid fingertip was 34.7°C. In the last EA session, the patient reported that the cold in her fingers and toes had eased and Raynaud's phenomenon, in which nail colour tone changed from white to red, had disappeared. In the cold-provocation test, before EA, the temperature recovery rates of mid fingertips after cold exposure reached over 80% in 20 min. In contrast, after EA had been completed, the temperature recovery rate exceeded 80% in 10 min, thus the delay of temperature recovery was alleviated.
Thiopurine S-methyltransferase (TPMT) assessment prior to starting thiopurine drug treatment; a pharmacogenomic test whose time has come
Authors: Ford L T , Berg J D
Published: March 2010

Thiopurine S-methyltransferase (TPMT) is involved in the metabolism of thiopurine drugs. Patients that due to genetic variation lack this enzyme or have lower levels than normal, can be adversely affected if normal doses of thiopurines are prescribed. The evidence for measuring TPMT prior to starting patients on thiopurine drug therapy has been reviewed and the various approaches to establishing a service considered. Until recently clinical guidelines on the use of the TPMT varied by medical specialty. This has now changed, with clear guidance encouraging clinicians to use the TPMT test prior to starting any patient on thiopurine therapy. The TPMT test is the first pharmacogenomic test that has crossed from research to routine use. Several analytical approaches can be taken to assess TPMT status. The use of phenotyping supported with genotyping on selected samples has emerged as the analytical model that has enabled national referral services to be developed to a high level in the UK. The National Health Service now has access to cost-effective and timely TPMT assay services, with two laboratories undertaking the majority of the work at national level and with several local services developing. There appears to be adequate capacity and an appropriate internal market to ensure that TPMT assay services are commensurate with the clinical demand.
Alterations in glycosylation as biomarkers for cancer detection
Authors: Reis Celso A , Osorio Hugo , Silva Luisa , Gomes Catarina , David Leonor
Published: March 2010

Glycoconjugates constitute a major class of biomolecules which include glycoproteins, glycosphingolipids and proteoglycans. Glycans are involved in several physiological and pathological conditions, such as host–pathogen interactions, cell differentiation, migration, tumour invasion and metastisation, cell trafficking and signalling. Cancer is associated with glycosylation alterations in glycoproteins and glycolipids. This review describes various aspects of protein glycosylation with the focus on alterations associated with human cancer. The application of these glycosylation modifications as biomarkers for cancer detection in tumour tissues and serological assays is summarised.
Sialadenoma papilliferum with potentially malignant features
Authors: Ide F , Kikuchi K , Kusama K , Kanazawa H
Published: March 2010

Sialadenoma papilliferum (SP) is a benign non-invasive lesion with slow and limited growth. This report describes an unusual SP that enlarged rapidly and presented as an extensive intraoral tumour highly suspicious for verrucous carcinoma. Radiographic resorption of the underlying bone was evident in the mandible. This type of destructive growth does not conform to any previously reported SP. Histological features were also atypical: surface verrucous hyperplasia and deeper florid cystic-duct adenoma. Overall, the SP is likely to be considered a borderline lesion with malignant potential. Four published cases of malignancy associated with SP showed completely different clinical and pathological settings, further obfuscating the concept of malignant SP.
Spindle cell melanocytic lesions—part I: an approach to compound naevoidal pattern lesions with spindle cell morphology and Spitzoid pattern lesions
Authors: Sade Shachar , Al Habeeb Ayman , Ghazarian Danny
Published: March 2010

Melanocytic lesions show great morphological diversity in their architecture and the cytomorphological appearance of their composite cells. Whereas functional melanocytes reveal a dendritic cytomorphology and territorial isolation, lesional naevomelanocytes and melanoma cells typically show epithelioid, spindled or mixed cytomorphologies and a range of architectural arrangements. Spindling is common to melanocytic lesions, and may be either a characteristic feature or a divergent appearance. The presence of spindle cells may mask the melanocytic nature of a lesion, and is often disconcerting, either because of its infrequent appearance in a particular lesion or its interpretation as a dedifferentiated phenotype. Spindle cell melanocytic lesions follow the full spectrum of potential biological outcomes, and difficulty may be experienced judging the nature of a lesion because of a lack of consistently reliable features to predict biological behaviour. Over time, recognition of numerous histomorphological features that may portend a more aggressive lesion have been identified. However, the translation of these features into a diagnostic entity requires a gestalt approach. Although most spindle cell melanocytic lesions can reliably be resolved with this standard approach, problem areas do exist and cause no end of grief to the surgical pathologist or dermatopathologist. In this review, the authors present their algorithmic approach to spindle cell melanocytic lesions and discuss each entity in turn, in order to (1) model a systematic approach to such lesions, and (2) provide familiarity with those melanocytic lesions that either typically or occasionally display a spindled cytomorphology.
Introducing a professional development framework for postgraduate medical supervisors in secondary care: considerations, constraints and challenges
Authors: Swanwick Tim , McKimm Judy , Clarke Robert
Published: March 2010

Purpose of study

As the duration of postgraduate training becomes shorter, direct patient contact time is reduced, and supervision becomes more distributed, there is a move to ‘professionalise’ postgraduate medical education. This paper reports an initiative in one postgraduate training institution (the London Deanery) to develop and introduce a developmental framework and system of portfolio-based review of educational supervisors in the secondary care setting.

Study design

16 acute, mental health, foundation and primary-care Trusts participated in a pilot project, which was subsequently evaluated using focus groups and a semistructured questionnaire.

Results

Thematic analysis of transcripts identified a number of considerations, constraints and challenges, important observations given the current policy intention of the UK health departments to introduce mandatory training and performance review for educational supervisors.

Conclusion

This pilot study shows that such a process can be implemented at local level if facilitated by a clear and unambiguous developmental framework that can be applied flexibly across all specialities. Systems of review also need to be simple and straightforward, take into account existing appraisal processes, and simultaneously address issues of motivation, recognition and reward.
Clinical experience of methotrexate in Crohn’s disease: response, safety and monitoring of treatment
Authors: Parker Richard , Dixit Anyinda , Fraser Aileen , Creed Tom J , Probert Chris S
Published: March 2010

Background

Methotrexate is an immunosuppressant used in the treatment of patients with Crohn’s disease who are intolerant or refractory to azathioprine.

Aim

To present clinical experience in terms of response, side effects and reason for cessation of methotrexate treatment as well as adherence to monitoring regimens.

Design

Retrospective review of case records of 37 patients taking methotrexate for Crohn’s disease at the Bristol Royal Infirmary, a large UK teaching hospital. Thirty-five patients used oral methotrexate.

Results

Response rate to methotrexate was 78% at 3 months. Adverse events were uncommon and rarely dangerous. Monitoring of treatment did not adhere to British Society of Gastroenterology guidelines.

Conclusion

Oral methotrexate is effective and safe in the treatment of Crohn’s disease. This is in contrast to findings of previous series, which have mainly reported on intramuscular methotrexate use. Monitoring of treatment is currently inadequate and consensus should be sought for a pragmatic monitoring schedule to resolve this important governance issue.
Malignant middle cerebral artery (MCA) infarction: pathophysiology, diagnosis and management
Authors: Treadwell Sean D , Thanvi Bhomraj
Published: March 2010

‘Malignant MCA infarction’ is the term used to describe rapid neurological deterioration due to the effects of space occupying cerebral oedema following middle cerebral artery (MCA) territory stroke. Early neurological decline and symptoms such as headache and vomiting should alert the clinician to this syndrome, supported by radiological evidence of cerebral oedema and mass effect in the context of large hemispheric infarction. The prognosis is generally poor, and death usually occurs as a result of transtentorial herniation and brainstem compression. Treatment options include general measures and pharmacological agents to limit the extent of oedema, and surgical decompression to relieve the pressure effects. Until recently there has been little evidence to guide appropriate treatment, though in the last few years randomised data have been published addressing the role of surgical decompression. A pooled analysis of three European randomised controlled trials suggests that hemicraniectomy performed within 48 h significantly reduces mortality, and improves functional outcome in selected patients, and this has been reflected in recent national guidelines.
CONFINED LENNARD–JONES POTENTIAL: A VARIATIONAL TREATMENT
Authors: SILVA F. R. , DRIGO FILHO E.
Published: March 2010

In this work, the energy eigenvalues for the confined Lennard–Jones potential are calculated through the Variational Method allied to the Supersymmetric Quantum Mechanics. Numerical results are obtained for different energy levels, parameters of the potential and values of confinement radius. In the limit, where this radius assumes great values, the results for the non-confined case are recovered.
κ-DEFORMED SNYDER SPACETIME
Authors: MELJANAC S. , MELJANAC D. , SAMSAROV A. , STOJIĆ M.
Published: March 2010

We present Lie-algebraic deformations of Minkowski space with undeformed Poincaré algebra. These deformations interpolate between Snyder and κ-Minkowski space. We find realizations of noncommutative coordinates in terms of commutative coordinates and derivatives. Deformed Leibniz rule, the coproduct structure and star product are found. Special cases, particularly Snyder and κ-Minkowski in Maggiore-type realizations are discussed. Our construction leads to a new class of deformed special relativity theories.
ON THE RUNNING OF THE COSMOLOGICAL CONSTANT IN QUANTUM GENERAL RELATIVITY
Authors: WARD B. F. L.
Published: March 2010

We present arguments that show what the running of the cosmological constant means when quantum general relativity is formulated following the prescription developed by Feynman.
WHEN WILL WE KNOW A MUON COLLIDER IS FEASIBLE? STATUS AND DIRECTIONS OF MUON ACCELERATOR R&D
Authors: SHILTSEV VLADIMIR
Published: March 2010

Over the last decade there has been significant progress in developing the concepts and technologies needed to produce, capture, accelerate and collide high intensity beams of muons. At present, a high-luminosity multi-TeV muon collider presents a viable option for the next generation of lepton–lepton collider, which is believed to be needed to fully explore high energy physics in the era following the LHC discoveries. This paper briefly reviews the status of the accelerator R&D, addresses the question of the feasibility of a Muon Collider, what needs to be done to prove it and presents projected timeline of the project.
THE INTERMEDIATE ENERGY ELASTIC SCATTERING OF PROTONS BY α-CLUSTER 20Ne AND 24Mg NUCLEI
Authors: BEREZHNOY Yu. A. , MIKHAILYUK V. P. , PILIPENKO V. V.
Published: March 2010

The multiple diffraction scattering theory and the α-cluster model with dispersion have been applied for calculations of the observables for the elastic scattering of intermediate energy protons by 20 Ne and 24 Mg nuclei. The target nuclei are considered as composed of the core (16 O nucleus) and additional α-clusters (one α-cluster for 20 Ne nucleus and a dumb-bell α-cluster configuration for 24 Mg nucleus). Taking into account the α-cluster configuration of the core, it was supposed that the additional α-cluster or center of mass of the dumb-bell are arranged with the most probability inside or outside of the core. The calculated observables for the elastic p–20 Ne and p–24 Mg scattering are in agreement with the existing experimental data. The influence of the deformed core contribution on the behavior of the calculated observables also is tested.
HADRONS IN STRONGLY INTERACTING MATTER
Authors: LEUPOLD STEFAN , METAG VOLKER , MOSEL ULRICH
Published: March 2010

We review the current status of theories and experiments aiming at an understanding and a determination of the properties of light vector and scalar mesons inside strongly interacting hadronic matter. Starting from a discussion of the relevant symmetries of QCD and their connection with the hadronic description through QCD sum rules we then discuss hadronic models used to calculate the in-medium self-energies of hadrons and their spectral functions. The difficulties to link these calculated properties to actual observables are emphasized. Finally, we review in detail all the running experiments searching for in-medium changes of vector and scalar mesons, both with relativistic heavy-ion reactions as well as with elementary reactions on (cold) nuclei. Inconsistencies among experimental results are discussed. While almost all experiments observe a considerable broadening of vector mesons inside the nuclear medium, no evidence for mass changes is observed in the majority of the experiments.
COLORFUL PATTERNS WITH DISCRETE PLANAR SYMMETRIES FROM DYNAMICAL SYSTEMS
Authors: LU JIAN , ZOU YURU , LI WENXIA
Published: March 2010

Automatic generation of colored patterns with discrete planar symmetries is considered from a dynamical system's point of view. Invariant mappings with such symmetries are constructed to serve as the density functions for the generation of colorful images.