bluuebunny/crossref_metadata_2025 huggingface dataset:
A deficiency in chloroplastic ferredoxin 2 facilitates effective photosynthetic capacity during long‐term high light acclimation in Arabidopsis thaliana
Authors: Liu Jun , Wang Peng , Liu Bing , Feng Dongru , Zhang Jie , Su Jianbin , Zhang Yang , Wang Jin–Fa , Wang Hong–Bin
Published: October 2013

Photosynthetic electron transport is the major energy source for cellular metabolism in plants, and also has the potential to generate excess reactive oxygen species that cause irreversible damage to photosynthetic apparatus under adverse conditions. Ferredoxins (Fds), as the electron‐distributing hub in the chloroplast, contribute to redox regulation and antioxidant defense. However, the steady‐state levels of photosynthetic Fd decrease in plants when they are exposed to environmental stress conditions. To understand the effect of Fd down‐regulation on plant growth, we characterized Arabidopsis thaliana plants lacking Fd2 (Fd2–KO) under long‐term high light (HL) conditions. Unexpectedly, Fd2–KO plants exhibited efficient photosynthetic capacity and stable thylakoid protein complexes. At the transcriptional level, photoprotection‐related genes were up‐regulated more in the mutant plants, suggesting that knockout Fd2 lines possess a relatively effective photo‐acclimatory responses involving enhanced plastid redox signaling. In contrast to the physiological characterization of Fd2–KO under short‐term HL, the plastoquinone pool returned to a relatively balanced redox state via elevated PGR5‐dependent cyclic electron flow during extended HL. fd2 pgr5 double mutant plants displayed severely impaired photosynthetic capacity under HL treatment, further supporting a role for PGR5 in adaptation to HL in the Fd2–KO plants. These results suggest potential benefits of reducing Fd levels in plants grown under long‐term HL conditions.
TCP3 interacts with R2R3‐MYB proteins, promotes flavonoid biosynthesis and negatively regulates the auxin response in Arabidopsis thaliana
Authors: Li Shutian , Zachgo Sabine
Published: October 2013

TCP proteins belong to the plant‐specific bHLH transcription factor family, and function as key regulators of diverse developmental processes. Functional redundancy amongst family members and post‐transcriptional down‐regulation by miRJAW of several TCP genes complicate their functional characterization. Here, we explore the role of TCP3 by analyzing transgenic plants expressing miRJAW‐resistant mTCP3 and dominant‐negative TCP3SRDX. Seedlings and seeds of mTCP3 plants were found to hyper‐accumulate flavonols, anthocyanins and proanthocyanidins, whereas levels of proanthocyanidins were slightly reduced in TCP3SRDX plants. R2R3‐MYB proteins control not only early flavonoid biosynthetic steps but also activate late flavonoid biosynthetic genes by forming ternary R2R3‐MYB/bHLH/WD40 (MBW) complexes. TCP3 interacted in yeast with R2R3‐MYB proteins, which was further confirmed in planta using BiFC experiments. Yeast three‐hybrid assays revealed that TCP3 significantly strengthened the transcriptional activation capacity of R2R3‐MYBs bound by the bHLH protein TT8. Transcriptome analysis of mTCP3 and TCP3SRDX plants supported a role for TCP3 in enhancing flavonoid biosynthesis. Moreover, several auxin‐related developmental abnormalities were observed in mTCP3 plants. Transcriptome data coupled with studies of an auxin response reporter and auxin efflux carriers showed that TCP3 negatively modulates the auxin response, probably by compromising auxin transport capacity. Genetic experiments revealed that the chalcone synthase mutant tt4‐11 lacking flavonoid biosynthesis abrogated the auxin‐related defects caused by mTCP3. Together, these data suggest that TCP3 interactions with R2R3‐MYBs lead to enhanced flavonoid production, which further negatively modulates the auxin response.
The Fate of PrP GPI‐Anchor Signal Peptide is Modulated by P238S Pathogenic Mutation
Authors: Guizzunti Gianni , Zurzolo Chiara
Published: October 2013

Glycosylphosphatidylinositol (GPI)‐anchored proteins are localized to the plasma membrane via a C‐terminally linked GPI anchor. The GPI anchor is added concomitantly to the cleavage of the carboxy‐terminal GPI‐anchor signal sequence, thereby causing the release of a C‐terminal hydrophobic peptide, whose fate has not yet been investigated. Here we followed the fate of the GPI‐attachment signal of the prion protein (PrP), a protein implicated in various types of transmissible neurodegenerative spongiform encephalopathies (TSE). The PrP GPI‐anchor signal sequence shows a remarkable and unusual degree of conservation across the species and contains two point mutations (M232R/T and P238S) that are responsible for genetic forms of prion disorders. We show that the PrP GPI‐anchor signal peptide (SP), but not the one from an unrelated GPI‐anchored protein (folate receptor), undergoes degradation via the proteasome. Moreover, the P238S point mutation partially protects the PrP GPI‐anchor SP from degradation. Our data provide the first attempt to address the fate of a GPI‐anchor SP and identify a role for the P238S mutation, suggesting the possibility that the PrP GPI‐anchor SP could play a role in neurodegenerative prion diseases.
External quality assessment in molecular immunohematology: the INSTAND proficiency test program
Authors: Flegel Willy A. , Chiosea Ion , Sachs Ulrich J. , Bein Gregor
Published: October 2013

Background

Genotyping for red blood cell (RBC), platelet (PLT), and granulocyte antigens is a new tool for clinical pathology, transfusion medicine services, and blood banks. Proficiency in laboratory tests can be established by external quality assessments (EQAs), which are required for clinical application in many health care systems. There are few EQAs for molecular immunohematology.

Study Design and Methods

We analyzed the participation and pass rates in an EQA for RBC, PLT, and granulocyte antigens. This EQA was distributed by INSTAND, a large nonprofit provider of proficiency tests, twice per year since Fall 2006 as EQA Number 235 Immunohematology A (molecular diagnostic). The coordinators defined at the outset which alleles are mandatory for detection.

Results

The number of participants steadily increased from 51 to 73 per proficiency by Fall 2012. More than 60 institutions utilized this EQA at least once a year. Approximately 80% of them participated in RBC, 68% in PLT, and 22% in granulocyte systems. With the exceptions of RHD (82%) and granulocytes (85%), pass rates exceeded 93%. While the pass rate increased for granulocyte and decreased for the ABO system, the pass rates for the other systems changed little over 6½ years.

Conclusions

The INSTAND proficiency test program was regularly used for EQA by many institutions, particularly in Central Europe. While the technical standards and pass rates in the participating laboratories were high, there has been little improvement in pass rates since 2006.
Development of a validated exam to assess physician transfusion medicine knowledge
Authors: Haspel Richard L. , Lin Yulia , Fisher Patrick , Ali Asma , Parks Eric ,   Biomedical Excellence for Safer Transfusion (BEST) Collaborative
Published: October 2013

Background

There is evidence that physicians lack adequate transfusion medicine knowledge. To design needs‐based educational interventions to address this gap, a validated assessment tool is required. Previously published exams have not been created or validated using rigorous psychometric methods.

Study Design and Methods

A modified Delphi method was used to achieve consensus regarding the essential knowledge and skills for physicians who transfuse blood products. To ensure content validity, members of an international organization of transfusion medicine experts (Biomedical Excellence for Safer Transfusion [BEST] Collaborative) participated in the exam design process. An exam, based on the most highly rated topics, was created and administered to individuals with a priori expected basic, intermediate, and expert levels of transfusion medicine knowledge. Rasch analysis, a psychometric technique used in high‐stakes medical licensure and board testing, was used to determine exam accuracy and precision.

Results

Thirty‐six topics achieved ratings sufficient to be considered for inclusion in the exam (content validity index > 0.8). A 23‐question exam was administered to 49 individuals. Mean scores for individuals with expected basic, intermediate, and expert knowledge were 42, 62, and 82%, respectively (p < 0.0001). The exam achieved good fit with the Rasch model.

Conclusion

A validated exam has now been created to accurately assess transfusion medicine knowledge. This exam can be used to determine knowledge deficits and assist in the design of curricula to improve blood product utilization.
Treatment of refractory thrombotic thrombocytopenic purpura with N‐acetylcysteine: a case report
Authors: Li Gloria W. , Rambally Siayareh , Kamboj Jasmine , Reilly Sean , Moake Joel L. , Udden Mark M. , Mims Martha P.
Published: October 2013

Background

Thrombotic thrombocytopenic purpura (TTP) is a life‐threatening disease resulting in systemic microvascular thrombosis. The disease is caused by excessive platelet (PLT) adhesion to ultra‐large (UL) von Willebrand factor (VWF) multimers inadequately cleaved by the processing enzyme ADAMTS‐13. While many cases respond to plasma exchange performed with or without concurrent corticosteroids, treatment of the 10% to 20% of patients with refractory disease is difficult. Experimental studies demonstrating that N‐acetylcysteine (NAC) inhibits PLT binding to endothelial cell–secreted and anchored UL VWF multimers suggest that NAC may be useful in the treatment of TTP.

Case Report

A 44‐year‐old woman presented with malaise, confusion, chest and abdominal pain, and transient visual loss. Laboratory results and peripheral blood smear were consistent with TTP. The patient was begun on plasma exchange and corticosteroid treatment, but after 10 days the PLT count was still less than 10.0 × 109/L and she developed a fever. Rituximab was initiated, but the patient's condition worsened and she became comatose. Antibiotics were initiated, but cultures remained sterile. After 3 days of coma and further clinical deterioration, treatment with NAC was begun. The patient received a loading dose of 150 mg/kg NAC intravenously (IV) over 1 hour. Within 18 hours the patient awakened abruptly and began communicating with medical personnel. Plasma exchange, corticosteroids, rituximab, and NAC infusion (150 mg/kg IV over 17 hr daily × 10 days) were continued and by Day 17 the PLT count was more than 50 × 109/L. The patient fully recovered and was discharged on Day 31.

Conclusion

This is the first complete report of a TTP patient treated with NAC. NAC was a safe and effective supplementary treatment for refractory TTP in this patient.
An innovative biologic recycling process of leukoreduction filters to produce active human antimicrobial peptides
Authors: Vossier Ludivine , Leon Fanny , Bachelier Cécile , Marchandin Hélène , Lehmann Sylvain , Leonetti Jean‐Paul , Brodolin Konstantin , Coste Joliette , Fournier‐Wirth Chantal
Published: October 2013

Background

Human neutrophil peptides (HNPs) 1 to 3 are the major antimicrobial peptides of the azurophilic granules of neutrophils. They represent an important arm of the innate immune system. Their production by chemical synthesis and recombinant technologies is expensive and limited by technical constraints due to their composition and the presence of three disulfide bonds.

Study Design and Methods

We have developed an original approach based on the purification of the natural human defensins HNPs 1 to 3 from neutrophils trapped on leukoreduction filters used in blood processing. The purification of HNPs 1 to 3 from these filters is performed in two steps: extraction of HNPs 1 to 3 retained in the filters followed by their immunoprecipitation. Studies were performed to determine the stability of defensins in the filters stored at room temperature. The activity of HNPs 1 to 3 obtained by our rapid protocol was validated by determining minimal inhibitory concentrations (MICs) against six reference bacterial strains and 12 clinical isolates.

Results

The human defensins HNPs 1 to 3 extracted from leukoreduction filters displayed high antimicrobial activity against tested strains, with MIC values between 0.12 and 1 μg/mL. Kinetics assays showed the appearance of activity 15 minutes after peptide addition. Moreover, we found that the HNPs 1 to 3 purified from leukoreduction filters that had been stored for 45 days at room temperature remained active.

Conclusion

Leukoreduction filters provide a rich and safe source of active human defensins HNPs 1 to 3. Moreover, the stability of the peptides in filters stored at room temperature allows envisaging a large‐scale development of the process.
The efficacy of cetirizine hydrochloride on the pruritus of cats with atopic dermatitis: a randomized, double‐blind, placebo‐controlled, crossover study
Authors: Wildermuth Kerstin , Zabel Sonja , Rosychuk Rod A. W.
Published: October 2013

Background

Various antihistamines have been used in the management of feline atopic dermatitis, with variable reported benefit. To date, there have been no randomized, double‐blind, placebo‐controlled, crossover clinical trials on the use of this drug class in cats.

Hypothesis/Objectives

To evaluate the clinical efficacy of cetirizine hydrochloride for the control of pruritus and dermatitis in cats diagnosed with atopic dermatitis.

Methods

In this randomized, double‐blind, placebo‐controlled crossover clinical trial, 21 client‐owned cats diagnosed with mild to moderate nonseasonal atopic dermatitis were randomly assigned to two groups. Cats in each group received either 1 mg/kg cetirizine hydrochloride or placebo once daily per os for 28 days followed by a 14 day wash‐out period. Treatments were then crossed over, and cats received placebo or cetirizine hydrochloride for another 28 days. Owners marked a pruritus severity scale before inclusion in the study and weekly throughout the entire study period. Lesions were scored by the clinician using aCanineAtopicDermatitisExtent andSeverityIndex (CADESI)‐03 modified for the cat before enrolment and at day 28 of each treatment.

Results

Nineteen cats completed the study. There were no statistically significant differences between treatment with cetirizine hydrochloride and placebo for modifiedCADESI‐03 or pruritus scores.

Conclusion and clinical importance

This study suggests that cetirizine hydrochloride cannot be recommended for the management of feline atopic dermatitis.
Transcription profile of chemokine receptors, cytokines and cytotoxic markers in peripheral blood of dogs with epitheliotropic cutaneous lymphoma
Authors: Chimura Naoki , Iio Aki , Ozaki Eiji , Mori Takashi , Ito Yusuke , Murayama Nobuo , Nagata Masahiko , Ide Kaori , Nishifuji Koji , Kamishina Hiroaki , Maeda Sadatoshi
Published: October 2013

Background

Mycosis fungoides (MF) is the most common form of canine epitheliotropic cutaneous lymphoma, which is characterized by the accumulation of neoplastic CD8+ T cells. Given that multifocal skin lesions are commonly seen in MF, neoplastic lymphocytes may actively migrate into the blood circulation.

Hypothesis/Objectives

Cytotoxic T cells with a skin‐homing phenotype could be increased in the blood circulation of dogs with MF.

Animals

Ten dogs with MF and 10 age‐matched healthy dogs were included.

Methods

The transcription levels of chemokine receptors, cytokines and cytotoxic markers in peripheral blood of dogs with MF were quantified by real‐time RT‐PCR.

Results

The dogs with MF had lower transcription levels of chemokine receptors associated with skin homing (CCR4), epitheliotropism (CXCR3), lymph node homing (CCR7), a type‐1 cytokine (LT‐α) and cytotoxic markers (perforin and granzyme B) in the circulation than healthy control dogs (P < 0.05).

Conclusions and clinical importance

The present results suggest that the number of peripheral cytotoxic T cells with a skin‐homing phenotype could be decreased in the peripheral blood of dogs with MF, which might be due to the sequestration of cytotoxic T cells in the lesional skin.
An in vitro study to determine the minimal bactericidal concentration of sodium hypochlorite (bleach) required to inhibit meticillin‐resistant Staphylococcus pseudintermedius strains isolated from canine skin
Authors: Pariser Marlene , Gard Sharon , Gram Dunbar , Schmeitzel Lynn
Published: October 2013

Background

Meticillin‐resistant Staphylococcus pseudintermedius (MRSP) is becoming a more common pathogen in animals treated in veterinary hospitals, raising concerns for transmission and possible contamination of the hospital itself. The identification of effective agents for the decontamination of veterinary patients and hospitals is crucial. Sodium hypochlorite (6.15%) or ‘bleach’ is an inexpensive and frequently used decontamination agent in human and veterinary hospitals and an adjunctive treatment for human patients. There are no published data on the minimal bactericidal concentration (MBC) of sodium hypochlorite (6.15%) for MRSP.

Hypothesis/Objectives

The objective of this study was to determine the MBC of sodium hypochlorite (6.15%) against MRSP strains isolated from canine skin.

Methods

In this in vitro study, 12 canine skin isolates were obtained from the Antech Diagnostics microbiology department. Twofold serial dilutions of sodium hypochlorite (6.15%) were allowed to react with each of the MRSP strains for 15 min, followed by overnight incubation on agar plates. Colonies on each plate were counted. This process was repeated in triplicate.

Results

The overall MBC for the canine skin‐isolated MRSP strains was 1:32, but most strains had an MBC between 1:64 and 1:128 dilution.

Conclusions and clinical importance

This study shows that sodium hypochlorite (6.15%) is an effective agent for decontamination at easily achievable concentrations.
Characterization of the complications associated with plasma exchange for thrombotic thrombocytopaenic purpura and related thrombotic microangiopathic anaemias: a single institution experience
Authors: McGuckin S. , Westwood J.‐P. , Webster H. , Collier D. , Leverett D. , Scully M.
Published: October 2013

Background

Plasma exchange (PEX) is a life‐saving therapeutic procedure in patients with thrombotic thrombocytopaenic purpura (TTP) and other thrombotic microangiopathic anaemias (TMAs). However, it may be associated with significant complications, exacerbating the morbidity and mortality in this patient group.

Study Design and Methods

We reviewed all PEX procedures over a 72‐month period, following the exclusive introduction of solvent–detergent double viral‐inactivated plasma in high‐volume users, such as TTP, in the United Kingdom (UK). We documented allergic reactions to plasma, citrate reactions, complications relating to central venous access insertion and venous thrombotic events (VTE) in 155 patient episodes and >2000 PEX procedures.

Results

The overall complication rate was low. Allergic plasma reactions occurred in 6·45% of the cohort with only one episode of acute anaphylaxis. Similarly, VTEs were 6·45%, not significantly greater than in medical patients receiving thromboprophylaxis, despite added potential risk factors in TTP. Citrate reactions were the most frequent complication documented, but toxicity was significantly reduced by administration of further calcium infusions during the PEX procedure. There were no serious central line infections and no catheter thrombosis.

Conclusion

Our data confirms that PEX continues to be a life‐saving procedure in the acute TTP setting and, the procedure was not associated with an increased mortality and limited morbidity.
Compliance with the current 12‐month deferral for male‐to‐male sex in Australia
Authors: Seed C. R. , Lucky T. T. , Waller D. , Wand H. , Lee J. F. , Wroth S. , McDonald A. , Pink J. , Wilson D. P. , Keller A. J.
Published: October 2013

Background and Objectives

In Australia since 2000, donors are deferred for 12 months since last male‐to‐male sexual contact. There is no estimate of the prevalence of non‐compliance (i.e. failure to disclose a risk during the predonation interview which would lead to deferral) with the policy in Australia; however, published studies elsewhere indicate a range of 0·8–11%. We investigated the rate of, timing and motivation for non‐compliance.

Materials and Methods

A nationally representative sample of donors who had made a recent donation negative for transfusion‐transmissible infection testing was surveyed using an anonymous, online instrument. Non‐compliance was considered as a ‘yes’ response to the current screening question. Non‐compliers were requested to define the timing of the last sexual contact relevant to their most recent donation. Univariate and multivariate regression analyses were used to define factors associated with non‐compliance.

Results

Of 14 476 responses from male donors, 34 (0·23%, 95% CI: 0·16–0·33%) were non‐compliant of whom 24 (0·17%, 95% CI: 0·11–0·25%) had contact within 6 months of donation. Factors significantly associated with non‐compliance included: multiple sexual partners, history of injecting drug use, perception of a lack of privacy during interview and preference for a computer‐based questionnaire.

Conclusion

Our study confirms high compliance (>99·7%) to the 12‐month deferral for male‐to‐male sex in Australia providing reassuring evidence for the efficacy of the screening question. Issues of ‘privacy’ and ‘discomfort’ associated with disclosure suggest the use of validated audio computer‐assisted structured interview as a possible option for improving compliance with the donor questionnaire.
COMPARISON BETWEEN NONCONTRAST COMPUTED TOMOGRAPHY AND MAGNETIC RESONANCE IMAGING FOR DETECTION AND CHARACTERIZATION OF THORACOLUMBAR MYELOPATHY CAUSED BY INTERVERTEBRAL DISK HERNIATION IN DOGS
Authors: Cooper Jocelyn J. , Young Benjamin D. , Griffin John F. , Fosgate Geoffrey T. , Levine Jonathan M.
Published: October 2013

Magnetic resonance imaging (MRI) and computed tomography (CT) are commonly used to evaluate dogs with thoracolumbar myelopathy; however, relative diagnostic sensitivities for these two modalities have not been previously reported. The purpose of this prospective study was to compare diagnostic sensitivity and observer agreement for MRI and CT in a group of dogs with thoracolumbar myelopathy due to surgically confirmed intervertebral disk herniation (IVDH). All included dogs had magnetic resonance (MR) imaging followed by noncontrast CT using standardized protocols. Three experienced observers interpreted each imaging study independently without knowledge of clinical or surgical findings. The operating surgeon was aware of MR findings but not CT findings at the time surgical findings were recorded. Forty‐four dogs met the inclusion criteria. The sensitivity of CT was 88.6% (79.5%–94.2%) and of MR was 98.5% (95% confidence interval, 94.1%–99.7%) for diagnosis of intervertebral disk herniation. Specificity was not calculated, as all dogs had IVDH at surgery. Magnetic resonance imaging was more accurate than CT for identifying the site of intervertebral disk herniation‐associated spinal cord compression and differentiating disk extrusion vs. protrusion. Computed tomography was less accurate for lesion localization in per acute cases, as well as for chondrodystrophic, female, older and smaller (<7 kg) dogs. Inter‐rater agreement was good for lesion lateralization for both MR and CT (κ = 0.687, 95% CI = 0.552, 0.822, P = 0.002, and κ = 0.692, 95% CI = 0.542, 0.842, P = 0.003). Findings from the current study indicated that MR imaging was more sensitive and accurate than noncontrast CT for diagnosis and characterization of thoracolumbar myelopathy due to IVDH in dogs.
Microsatellite variability of sulfonylurea‐resistant and susceptible populations of Schoenoplectus juncoides (Cyperaceae) in Kinki, Japan
Authors: Yamada Y , Tominaga T , Ohsako T
Published: October 2013

Schoenoplectus juncoides is one of the most harmful weeds found in East Asian paddy fields. Recent emergence of biotypes that are resistant to the herbicide sulfonylurea (SU) has made weed control difficult. To examine the effect of the evolution of this herbicide resistance on genetic diversity within local populations, we investigated microsatellite variability within and among paddy field populations of S. juncoides in Kinki, Japan. In vivo assay of acetolactate synthase activity and root elongation assay in the presence of SU revealed that of 21 populations, five were sulfonylurea‐susceptible (SU‐S) and eight were completely sulfonylurea‐resistant (SU‐R). The remaining eight populations were a mixture of SU‐S and SU‐R individuals. The average gene diversity for SU‐R populations (HS = 0.168) was lower than those for SU‐S (HS = 0.256) and mixed (HS = 0.209) populations, but the difference was not significant. This indicates that positive selection for SU‐R phenotype did not cause a genome‐wide reduction in genetic diversity. Genetic differentiation among S. juncoides populations was higher than that observed for most weed species studied previously. Although populations in neighbouring paddy fields showed a high level of differentiation, Bayesian clustering analyses suggested that some level of gene flow occurs among them and that the genetic exchange or colonisation between neighbouring populations could contribute to the geographical expansion of the resistant allele.
Prevalence and Molecular Characteristics of Methicillin‐Resistant Staphylococcus aureus (MRSA) in Organic Pig Herds in The Netherlands
Authors: van de Vijver L. P. L. , Tulinski P. , Bondt N. , Mevius D. , Verwer C.
Published: October 2013

The prevalence of the methicillin‐resistant Staphylococcus aureus (MRSA) among conventional pig herds in the Netherlands is high (around 71%). Nevertheless, information about the prevalence of MRSA among organic pig herds is lacking. Here, we report a study on 24 of the 49 organic pig herds in the Netherlands. The prevalence of MRSA positive herds showed to be 21%. The genetic characteristics of the MRSA isolates were similar to MRSA CC398 described in conventional pigs except one exceptional HA‐MRSA CC30 found in one herd, which was presumably caused by human to animal transmission. This resulted in a prevalence of MRSA CC398 in the organic herds of 16.7%.
Clonal Spread of Salmonella enterica Serovar Infantis in Serbia: Acquisition of Mutations in the Topoisomerase Genes gyrA and parC Leads to Increased Resistance to Fluoroquinolones
Authors: Velhner M. , Kozoderović G. , Grego E. , Galić N. , Stojanov I. , Jelesić Z. , Kehrenberg C.
Published: October 2013

Quinolone‐resistant Salmonella Infantis (n = 64) isolated from human stool samples, food and poultry during the years 2006–2011 were analysed for their resistance phenotypes, macrorestriction patterns and molecular mechanisms of decreased susceptibility to fluoroquinolones. Minimum inhibitory concentrations (MICs) of nalidixic acid (NAL) and ciprofloxacin (CIP) were determined by the agar dilution procedure, and the susceptibility to additional antimicrobial agents was determined by the disc diffusion method. To assess the influence of enhanced efflux activity, MICs were determined in the presence and absence of the inhibitor PAβN. The results of pulsed‐field gel electrophoresis (PFGE) typing revealed that quinolone‐resistant S. Infantis in Serbia had similar or indistinguishable PFGE profiles, suggesting a clonal spread. All S. Infantis showed combined resistance to NAL and tetracycline, whereas multiple drug resistance to three or more antibiotic classes was rare (2 isolates of human origin). The MICs ranged between 512 and 1024 μg/mL for NAL and 0.125–2 μg/mL for CIP. A single‐point mutation in the gene gyrA leading to a Ser83→Tyr exchange was detected in all isolates, and a second exchange (Ser80→Arg) in the gene parC was only present in eight S. Infantis isolates exhibiting slightly higher MICs of CIP (2 μg/mL). The inhibitor PAβN decreased the MIC values of CIP by two dilution steps and of NAL by at minimum 3–6 dilution steps, indicating that enhanced efflux plays an important role in quinolone resistance in these isolates. The plasmid‐mediated genes qnr, aac(6′)‐lb‐cr and qepA were not detected by PCR assays.
The importance of the smooth muscle cytoskeleton to preterm labour
Authors: Morgan Kathleen G.
Published: October 2013

New Findings

What is the topic of this review?

This report discusses current work on the cytoskeletal dynamics in myometrial smooth muscle and its possible connection to the function of the myometrium in the setting of normal and preterm labour.

What advances does it highlight?

The report highlights findings from my research group on changes in focal adhesion dynamics and extracellular signal‐regulated kinase signalling in both rodent and human pregnancy that appear to be a contributing cause of the onset of labour.

Multiple mechanisms have been shown to regulate the onset of labour in a co‐operative and complex manner. One factor, myometrial stretch and associated increases in wall tension, has been implicated clinically in the initiation of labour and especially the aetiology of preterm labour. Recent work on the mechanisms involved has led to the finding that the intracellular Ca2+ requirement for activation of the myometrial contractile filaments increases during gestation. The decreased Ca2+ sensitivity correlates with an increase in the expression of caldesmon, an actin‐binding protein and inhibitor of myosin activation, during pregnancy. In late pregnancy, an increase in extracellular signal‐regulated kinase‐mediated caldesmon phosphorylation occurs, which appears to reverse the inhibitory action of caldesmon during labour. Force generated by the myometrial contractile filaments is communicated across the plasmalemma to the uterine wall through focal adhesions. Phospho‐tyrosine screening and mass spectrometry of stretched myometrial samples identified several stretch‐activated focal adhesion proteins. This Src‐mediated focal adhesion signalling appears to provide a tunable, i.e. regulated, tension sensor and force transmitter in the myometrial cell. In other parallel studies, biophysical measurements of smooth muscle compliance at both the cellular and tissue levels suggest that decreases in cellular compliance due to changing interactions of the actin cytoskeleton with the focal adhesions may also promote increases in uterine wall tension. These results, taken together, suggest that focal adhesion proteins and their interaction with the cytoskeleton may present a new mode of regulation of uterine contractility.
Cortical control of the autonomic nervous system
Authors: Cechetto David F.
Published: October 2013

New Findings

What is the topic of this review?

The pathways in the brain by which visceral information, in particular cardiopulmonary afferents, ascend to the cerebral cortex have been delineated in animal models. Studies using functional magnetic resonance imaging in humans have confirmed what was known from the animal studies and established the critical sites in the cerebral cortex of humans for autonomic control and the significance of these sites for cognitive emotional function.

What advances does it highlight?

Stimulation of cardiopulmonary afferents in humans has consistently resulted in activation in the insular cortex and the anterior cingulate cortex. It has been shown that individuals who are characterized as cardiovascular responders to mental stress have a different pattern of activity in the cortex related to the cardiac changes.

A number of animal studies in the rat and cat have been particularly useful for determining the pathways and the sites in the forebrain and cortex that are responsible for autonomic control. For example, these experiments have demonstrated that there is a viscerotopically organized pathway, with the first site of termination in the nucleus of the solitary tract and with subsequent relays in the parabrachial nucleus and the ventroposterior parvocellular nucleus of the thalamus before final visceral afferent inputs in the insular cortex. Several neuroimaging studies in humans, using cardiopulmonary manipulations, have confirmed the importance of the insular cortex as a site of for visceral afferent inputs. The anterior cingulate cortex has also been implicated in cardiopulmonary control. Both the insular cortex and the infralimbic cortex have been shown to be involved in descending control of the cardiovascular system. Neuroimaging with functional magnetic resonance imaging has demonstrated that the cortical autonomic control pathways are different in individuals who are characterized as cardiovascular reactors to mental stress. There is evidence that this alteration in pathways in the cortex may be due to past experiences, including childhood trauma.
Confidence intervals for the parameters estimated from simulated O2 uptake kinetics: effects of different data treatments
Authors: Francescato M. P. , Cettolo V. , Bellio R.
Published: October 2013

New Findings

What is the central question of this study?

Is the accuracy and/or precision of the O2 uptake kinetics parameters, estimated by non‐linear regression, affected by different data treatments applied to reduce the noise of breath fluctuations?

What is the main finding and its importance?

Simulations showed that, even after the averaging of more repetitions, the width of the asymptotic confidence intervals was narrower than the real ones, in particular when the O2 uptake responses were resampled at time intervals shorter than the average breath duration (e.g. 1 s). The reasons for this discrepancy were investigated, allowing us to identify simple methods to obtain the correct confidence interval of the O2 uptake kinetics parameters.

The behaviour of pulmonary O2 uptake following a moderate‐intensity step exercise increment is usually described by a first brief increase, followed by a second exponential time course reaching the new steady state (phase II). The parameters describing the phase II kinetics are investigated by applying different data treatments to the acquired O2 uptake data to reduce the effects of their noise before running a non‐linear regression procedure. The effects of different data treatments (nothing, resampling at various time intervals or averaging of more repetitions) on the precision and/or accuracy of the kinetics parameters estimated by non‐linear regression with a simple mono‐exponential model were investigated by artificially generating 105 simulated responses with average breath duration of 3.5 s. The simulations showed that, whatever the explored data treatment, the average estimated parameters were close to the theoretical ones. Nevertheless, in all the explored conditions, the non‐linear regression provided narrower asymptotic confidence intervals than the real ones. In particular, when the responses were resampled at 1 s time intervals, the width of the asymptotic confidence interval for the time constant was 50% of the real one, even after the averaging of more repetitions. The reasons for this discrepancy were investigated further, allowing us to identify some methods to obtain the correct confidence interval of the O2 uptake kinetics parameters. The simplest method to obtain an asymptotic confidence interval close to the real one is to average more responses resampled to a time interval slightly longer than the average breath duration.
Thermal Diffusion and Diffusion Thermo Effects on Peristaltic Flow of Sisko Fluid in Nonuniform Channel With Dissipative Heating
Authors: Shafie Sharidan , Ullah Mehmood Obaid , Mustapha Norzieha
Published: October 2013

This investigation deals with thermal diffusion and diffusion thermo effects on the peristaltic flow of a Sisko fluid in an asymmetric channel. The mode of dissipative heat transfer is taken into account with nonuniform wall temperatures. Long wavelength approximation is utilized. Solutions for the highly nonlinear coupled governing equations involving power law index as an exponent are derived by employing the perturbation technique in a Sisko fluid parameter. Closed form solutions for the stream function, the axial pressure gradient, the skin friction, the temperature, the concentration, and the Nusselt number are presented. Effects of various interesting parameters are graphically interpreted. A comparative study between Newtonian, shear thinning, and shear thickening fluids is also presented. Comparison with published results for the case of viscous fluid is observed in good agreement.
A Fundamental Study on the Heat Partition Ratio of Vehicle Disk Brakes
Authors: Loizou Andreas , Sheng Qi Hong , Day Andrew J.
Published: October 2013

The interface tribolayer (ITL) in an automotive brake friction pair is a layer of material created from transfer films, wear particles, and surface transformations between the rotor and stator. Its presence in a brake friction interface has been proven, e.g., by the existence of a temperature “jump” across the friction interface. In this paper, two 1D static transient heat transfer models have been used to investigate the ITL behavior and obtain an equivalent thermal conductance value which will reduce computational requirements and software restrictions. The approach is developed into a more realistic 2D coupled temperature–displacement model using commercial finite element analysis (FEA) software (abaqus) that utilizes the contact pressure, real contact area, and the ITL equivalent thermal conductance to estimate the effective thermal conductance at the friction interface. Subsequently, the effective thermal conductance relationship is combined with the 2-D coupled temperature–displacement model to provide a new method of heat partition prediction in brake friction pairs where heat partition is neither uniform nor constant with time.
Effect of process temperature on the structural and electrical properties of atomic layer deposited ZrO2 films using tris(dimethylamino) cyclopentadienyl zirconium precursor
Authors: Chan Won Dong , Rhee Shi-Woo
Published: October 2013

The authors investigate the deposition of ZrO2 by atomic layer deposition (ALD) process using tris(dimethylamino) cyclopentadienyl zirconium (Cp-Zr) as a precursor, and the effect of deposition temperature on the structural and electrical properties of ZrO2 thin films are studied. The ALD process window of Cp-Zr is found at 300–350 °C, and no noticeable change in the film composition occurs within the ALD process window and the films are all stoichiometric. However, the crystallinity of the film is significantly affected by the deposition temperature. At 300 °C, only the cubic and tetragonal phases are detected, while the monoclinic peak starts to appear at 325 °C. Consequently, the highest dielectric constant (35.8) is observed for the ZrO2 films deposited at 300 °C. In contrast, ZrO2 films deposited at 350 °C show the lowest leakage current. This trend is due to the lower carbon impurity contents along with the increase in deposition temperature. To study the electrical properties of ZrO2 films in more detail, capacitance–voltage hysteresis measurements are carried out; the hysteresis is reduced abruptly with an increase in deposition temperature.
Fully 3D iterative CT reconstruction using polar coordinates
Authors: Thibaudeau Christian , Leroux Jean‐Daniel , Fontaine Réjean , Lecomte Roger
Published: October 2013

Purpose:

This paper demonstrates the feasibility of fully 3D iterative computed tomography reconstruction of highly resolved fields of view using polar coordinates.

Methods:

System matrix is computed using a ray‐tracing approach in cylindrical or spherical coordinates. By using polar symmetries inherent to the acquisition geometry, the system matrix size can be reduced by a factor corresponding to the number of acquired projections. Such an important decrease in size allows the system matrix to be precomputed, and loaded all at once into memory prior to reconstruction. By carefully ordering the field of view voxels and the sinogram data, reconstruction speed is also enhanced by a cache‐oblivious computer implementation. The reconstruction algorithm is also compatible with the ordered‐subsets acceleration method. A final polar‐to‐Cartesian transformation is applied to the reconstructed image in order to allow proper visualization.

Results:

The ray‐tracing and reconstruction algorithms were implemented in polar representation. Large 3D system matrices were calculated in cylindrical and spherical coordinates, and the performance assessed against Cartesian ray‐tracers in terms of speed and memory requirements. Images of analytical phantoms were successfully reconstructed in both cylindrical and spherical coordinates. Fully 3D images of phantoms and small animals were acquired with a Gamma Medica Triumph X‐O small animal CT scanner and reconstructed using the manufacturerˈs software and the proposed polar approach to demonstrate the accuracy and robustness of the later. The noise was found to be reduced while preserving the same level of spatial resolution, without noticeable polar artifacts.

Conclusions:

Under a reasonable set of assumptions, the memory size of the system matrix can be reduced by a factor corresponding to the number of projections. Using this strategy, iterative reconstruction from high resolution clinical and preclinical systems can be more easily performed using general‐purpose personal computers.
The impact of leaf width and plan complexity on DMLC tracking of prostate intensity modulated arc therapy
Authors: Pommer Tobias , Falk Marianne , Poulsen Per Rugaard , Keall Paul J. , O’Brien Ricky T. , Munck af Rosenschöld Per
Published: October 2013

Purpose:

Intensity modulated arc therapy (IMAT) is commonly used to treat prostate cancer. The purpose of this study was to evaluate the impact of leaf width and plan complexity on dynamic multileaf collimator (DMLC) tracking for prostate motion management during IMAT treatments.

Methods:

Prostate IMAT plans were delivered with either a high‐definition MLC (HDMLC) or a Millennium MLC (M‐MLC) (0.25 and 0.50 cm central leaf width, respectively), with and without DMLC tracking, to a dosimetric phantom that reproduced four prostate motion traces. The plan complexity was varied by applying leaf position constraints during plan optimization. A subset of the M‐MLC plans was converted for delivery with the HDMLC, isolating the effect of the different leaf widths. The gamma index was used for evaluation. Tracking errors caused by target localization, leaf fitting, and leaf adjustment were analyzed.

Results:

The gamma pass rate was significantly improved with DMLC tracking compared to no tracking (p < 0.001). With DMLC tracking, the average gamma index pass rate was 98.6% (range 94.8%–100%) with the HDMLC and 98.1% (range 95.4%–99.7%) with the M‐MLC, using 3%, 3 mm criteria and the planned dose as reference. The corresponding pass rates without tracking were 87.6% (range 76.2%–94.7%) and 91.1% (range 81.4%–97.6%), respectively. Decreased plan complexity improved the pass rate when static target measurements were used as reference, but not with the planned dose as reference. The main cause of tracking errors was leaf fitting errors, which were decreased by 42% by halving the leaf width.

Conclusions:

DMLC tracking successfully compensated for the prostate motion. The finer leaf width of the HDMLC improved the tracking accuracy compared to the M‐MLC. The tracking improvement with limited plan complexity was small and not discernible when using the planned dose as reference.
Three-dimensional multiple-source focalization in an uncertain ocean environment
Authors: Tollefsen Dag , Dosso Stan E.
Published: October 2013

This letter develops a Bayesian focalization approach for three-dimensional localization of an unknown number of sources in shallow water with uncertain environmental properties. The algorithm minimizes the Bayesian information criterion using adaptive hybrid optimization for environmental parameters, Metropolis sampling for source bearing, and Gibbs sampling for source ranges and depths. Maximum-likelihood expressions are used for unknown complex source strengths and noise variance, which allows these parameters to be sampled implicitly. An efficient scheme for adding/deleting sources is used during the optimization. A synthetic example considers localizing a quiet source in the presence of multiple interferers using a horizontal line array.
Preparation of Sticky Escherichia coli through Surface Display of an Adhesive Catecholamine Moiety
Authors: Park Joseph P. , Choi Min-Jung , Kim Se Hun , Lee Seung Hwan , Lee Haeshin
Published: October 2013

Mussels attach to virtually all types of inorganic and organic surfaces in aqueous environments, and catecholamines composed of 3,4-dihydroxy-
l
-phenylalanine (DOPA), lysine, and histidine in mussel adhesive proteins play a key role in the robust adhesion. DOPA is an unusual catecholic amino acid, and its side chain is called catechol. In this study, we displayed the adhesive moiety of DOPA-histidine on
Escherichia coli
surfaces using outer membrane protein W as an anchoring motif for the first time. Localization of catecholamines on the cell surface was confirmed by Western blot and immunofluorescence microscopy. Furthermore, cell-to-cell cohesion (i.e., cellular aggregation) induced by the displayed catecholamine and synthesis of gold nanoparticles on the cell surface support functional display of adhesive catecholamines. The engineered
E. coli
exhibited significant adhesion onto various material surfaces, including silica and glass microparticles, gold, titanium, silicon, poly(ethylene terephthalate), poly(urethane), and poly(dimethylsiloxane). The uniqueness of this approach utilizing the engineered sticky
E. coli
is that no chemistry for cell attachment are necessary, and the ability of spontaneous
E. coli
attachment allows one to immobilize the cells on challenging material surfaces such as synthetic polymers. Therefore, we envision that mussel-inspired catecholamine yielded sticky
E. coli
that can be used as a new type of engineered microbe for various emerging fields, such as whole living cell attachment on versatile material surfaces, cell-to-cell communication systems, and many others.
Bacteriophage Orphan DNA Methyltransferases: Insights from Their Bacterial Origin, Function, and Occurrence
Authors: Murphy James , Mahony Jennifer , Ainsworth Stuart , Nauta Arjen , van Sinderen Douwe
Published: October 2013

Type II DNA methyltransferases (MTases) are enzymes found ubiquitously in the prokaryotic world, where they play important roles in several cellular processes, such as host protection and epigenetic regulation. Three classes of type II MTases have been identified thus far in bacteria which function in transferring a methyl group from
S
-adenosyl-
l
-methionine (SAM) to a target nucleotide base, forming N-6-methyladenine (class I), N-4-methylcytosine (class II), or C-5-methylcytosine (class III). Often, these MTases are associated with a cognate restriction endonuclease (REase) to form a restriction-modification (R-M) system protecting bacterial cells from invasion by foreign DNA. When MTases exist alone, which are then termed orphan MTases, they are believed to be mainly involved in regulatory activities in the bacterial cell. Genomes of various lytic and lysogenic phages have been shown to encode multi- and mono-specific orphan MTases that have the ability to confer protection from restriction endonucleases of their bacterial host(s). The ability of a phage to overcome R-M and other phage-targeting resistance systems can be detrimental to particular biotechnological processes such as dairy fermentations. Conversely, as phages may also be beneficial in certain areas such as phage therapy, phages with additional resistance to host defenses may prolong the effectiveness of the therapy. This minireview will focus on bacteriophage-encoded MTases, their prevalence and diversity, as well as their potential origin and function.