bluuebunny/crossref_metadata_2025 huggingface dataset:
Dexmedetomidine vs midazolam as preanesthetic medication in children: a meta‐analysis of randomized controlled trials
Authors: Pasin Laura , Febres Daniela , Testa Valentina , Frati Elena , Borghi Giovanni , Landoni Giovanni , Zangrillo Alberto
Published: January 2015

Introduction

The preoperative period is a stressing occurrence for most people undergoing surgery, in particular children. Approximately 50–75% of children undergoing surgery develop anxiety which is associated with distress on emergence from anesthesia and with later postoperative behavioral problems. Premedication, commonly performed with benzodiazepines, reduces preoperative anxiety, facilitates separation from parents, and promotes acceptance of mask induction. Dexmedetomidine is a highly selective α2‐agonist with sedative and analgesic properties. A meta‐analysis of all randomized controlled trials (RCTs) on dexmedetomidine versus midazolam was performed to evaluate its efficacy in improving perioperative sedation and analgesia, and in reducing postoperative agitation when used as a preanesthetic medication in children.

Methods

Studies were independently searched in PubMed, BioMedCentral, Embase, and the Cochrane Central Register of clinical trials and updated on August 15th, 2014.

Primary outcomes were represented by improved sedation at separation from parents, at induction of anesthesia, and reduction in postoperative agitation. Secondary outcomes were reduction in rescue analgesic drugs, and duration of surgery and anesthesia. Inclusion criteria were random allocation to treatment and comparison between dexmedetomidine and midazolam. Exclusion criteria were adult studies, duplicate publications, intravenous administration, and no data on main outcomes.

Results

Data from 1033 children in 13 randomized trials were analyzed. Overall, in the dexmedetomidine group there was a higher incidence of satisfactory sedation at separation from parents (314 of 424 [74%] in the dexmedetomidine group vs 196 of 391 [50%] in the midazolam group, RR = 1.30 [1.05–1.62], P = 0.02), a reduced incidence of postoperative agitation (14 of 140 [10%] vs 56 of 141 [40%], RR = 0.31 [0.13–0.73], P = 0.008), and a significant reduction in the rescue doses of analgesic drugs (49 of 241 [20%] vs 95 of 243 [39%], RR = 0.52 [0.39–0.70], P < 0.001). There was no evidence of a higher incidence of satisfactory sedation at anesthesia induction or any reduction of duration of surgery and anesthesia.

Conclusions

Dexmedetomidine is effective in decreasing anxiety upon separation from parents, decreasing postoperative agitation, and providing more effective postoperative analgesia when compared with midazolam.
A randomized comparison of the i‐gel™ with the self‐pressurized air‐Q™ intubating laryngeal airway in children
Authors: Kim Min‐Soo , Lee Jae Hoon , Han Sang Won , Im Young Jae , Kang Hyo Jong , Lee Jeong‐Rim
Published: January 2015

Background

Supraglottic airway devices with noninflatable cuff have advantages in omitting the cuff pressure monitoring and reducing potential pharyngolaryngeal complications. Typical devices without cuff inflation available in children are the i‐gel™ and the self‐pressurized air‐Q™ intubating laryngeal airway (air‐Q SP). To date, there is no comparative study between these devices in pediatric patients.

Aim

The purpose of this randomized study was to compare the i‐gel™ and the self‐pressurized air‐Q™ intubating laryngeal airway (air‐Q SP) in children undergoing general anesthesia.

Methods

Eighty children, 1–108 months of age, 7–30 kg of weight, and scheduled for elective surgery in which supraglottic airway devices would be suitable for airway management, were randomly assigned to either the i‐gel or the air‐Q SP. Oropharyngeal leak pressure and fiberoptic view were assessed three times as follows: after insertion and fixation of the device, 10 min after initial assessment, and after completion of surgery. We also assessed insertion parameters and complications.

Results

Insertion of the i‐gel was regarded as significantly easier compared to the air‐Q SP (P = 0.04). Compared to the air‐Q SP group, the i‐gel group had significantly higher oropharyngeal leak pressures at all measurement points and significantly lower frequencies of gastric insufflation at 10 min after initial assessment and completion of surgery. The air‐Q SP group had better fiberoptic views than the i‐gel group at all measurement points.

Conclusion

Our results showed that the i‐gel had easier insertion and better sealing function, and the air‐Q SP provided improved fiberoptic views in children requiring general anesthesia.
Determination of the 95% effective dose of remifentanil for the prevention of coughing during extubation in children undergoing tonsillectomy (with or without adenoidectomy)
Authors: Park Yong‐Hee , Chung Eun‐Jin , Lee Ji‐Hyun , Kim Jin‐Tae , Kim Chong‐Sung , Kim Hee‐Soo
Published: January 2015

Background

Limited data are available regarding the 95% effective dose (ED95) of remifentanil to prevent the cough response during emergence from general anesthesia in children.

Methods

This study included 40 patients aged 3–12 years who underwent elective tonsillectomy with or without adenoidectomy. A predetermined remifentanil dose was infused continuously with desflurane during surgery and was continued until extubation. In the emergence period, the cough response during awake extubation was assessed to determine the remifentanil dose for the next patient. The first patient received remifentanil at the rate of 0.01 μg·kg−1·min−1, and subsequent patients received a 0.01 μg·kg−1·min−1 higher dose than the previous patient if there was more than moderate coughing detected, and the patient after those with less than mild coughing received either the same dose (95% probability) or a 0.01 μg·kg−1·min−1 lower dose (5% probability) using the biased coin design. Times to extubation and adverse events were recorded. The ED95 was calculated using the maximum‐likelihood estimation.

Results

The ED95 of remifentanil for preventing coughing during extubation was 0.060 μg·kg−1·min−1 (95% confidence interval, 0.037–0.068). There was moderate coughing in all groups receiving 0.01–0.06 μg·kg−1·min−1 of remifentanil, but no cough response occurred in the group receiving remifentanil 0.07 μg·kg−1·min−1. Time to extubation was weakly correlated with remifentanil infusion rate (r = 0.331). One patient who received remifentanil 0.07 μg·kg−1·min−1 showed desaturation over 5 s immediately after extubation, but recovered after receiving 100% oxygen.

Conclusion

The ED95 of the continuous remifentanil infusion rate was 0.060 μg·kg−1·min−1 to prevent the cough response during extubation in children after tonsillectomy.
Efficacy of the Japanese herbal medicine rikkunshito in infants with gastroesophageal reflux disease
Authors: Otake Kohei , Uchida Keiichi , Mori Koichiro , Ide Shozo , Koike Yuhki , Takamura Mitsuyuki , Inoue Mikihiro , Kusunoki Masato
Published: January 2015

Background

Gastroesophageal reflux disease (GERD) in infants is among the most common reason for physician consultation worldwide. A traditional Japanese medicine, rikkunshito (RKT), is effective for GERD in adult and pediatric patients. The aim of this study was to evaluate the efficacy and safety of RKT in infants with GERD.

Methods

Fifty‐four infants were referred to between July 2004 and December 2012 for evaluation and treatment of GERD. All infants had failure to thrive. We excluded nine patients with cow's milk protein allergy, neurological impairment or surgical indications. We retrospectively reviewed the clinical records of 45 infants with GERD. Twenty‐nine infants were treated with RKT (TJ‐43; 0.3 g/kg/day; RKT group), and 16 infants were treated with mosapride citrate at 0.5 mg/kg/day (mosapride group). The primary endpoint was RKT‐induced relief of clinical symptoms and bodyweight gain in infants with GERD.

Results

After 3 months of treatment, the frequency of vomiting per day was significantly lower in the RKT group than in the mosapride group (P = 0.0146) and the weight Z‐score was significantly higher in the RKT group than in the mosapride group (RKT group, −2.5 ± 1.5 vs mosapride group, −5.0 ± 2.0; P = 0.0386). No adverse effects were noted in either group.

Conclusions

RKT may be safe and effective for relief of GER symptoms and for bodyweight gain in infants with GERD.
Dyadic Effects of Individual and Friend on Physical Activity in College Students
Authors: Kim Gwang Suk , Lee Chung Yul , Kim In Sook , Lee Tae Hwa , Cho Eunhee , Lee Hyeonkyeong , McCreary Linda L. , Kim Su Hee
Published: January 2015

Objective

Physical activity (PA) tends to decline throughout the college years, and close friends’ influence is known to be an important factor in maintaining PA. This study examined the actor effect and partner effect between an individual and his/her friend regarding the influence of self‐efficacy and social support on PA among Korean college students.

Design and Sample

Cross‐sectional survey data from 108 pairs of individual students and friends were analyzed.

Measures

The survey questionnaire measured PA, self‐efficacy toward exercise, social support for PA, anxiety and depression, community environments, and perceived health status. Structural equation modeling with path analysis was conducted to test Actor‐Partner Interdependence Model (APIM) explaining close relationships on PA.

Results

One‐sided partner effect that friends' perceived friend support was directly related to individual's PA (β = 0.20, p < .05) was revealed. Regarding actor effects, self‐efficacy was directly related to higher levels of PA for individual and friend. Perceived health status was related to higher level of individuals’ PA.

Conclusions

These results suggest a role for public health nurses in developing interventions for college‐aged young adults that promotes friend support for PA as well as individual self‐efficacy toward PA, to engage young adults in establishing lifelong health‐promoting PA.
Changes in work affect in response to lunchtime walking in previously physically inactive employees: A randomized trial
Authors: Thøgersen‐Ntoumani C. , Loughren E. A. , Kinnafick F.‐E. , Taylor I. M. , Duda J. L. , Fox K. R.
Published: January 2015

Physical activity may regulate affective experiences at work, but controlled studies are needed and there has been a reliance on retrospective accounts of experience. The purpose of the present study was to examine the effect of lunchtime walks on momentary work affect at the individual and group levels. Physically inactive employees (N = 56; M age = 47.68; 92.86% female) from a large university in the UK were randomized to immediate treatment or delayed treatment (DT). The DT participants completed both a control and intervention period. During the intervention period, participants partook in three weekly 30‐min lunchtime group‐led walks for 10 weeks. They completed twice daily affective reports at work (morning and afternoon) using mobile phones on two randomly chosen days per week. Multilevel modeling was used to analyze the data. Lunchtime walks improved enthusiasm, relaxation, and nervousness at work, although the pattern of results differed depending on whether between‐group or within‐person analyses were conducted. The intervention was effective in changing some affective states and may have broader implications for public health and workplace performance.
Time trends in physical activity from 1982 to 2012 in Finland
Authors: Borodulin K. , Harald K. , Jousilahti P. , Laatikainen T. , Männistö S. , Vartiainen E.
Published: January 2015

The aim of this study was to examine population trends from 1982 to 2012 in Finland for leisure time physical activity (LTPA), commuting physical activity (CPA), occupational physical activity (OPA), and total physical activity. Furthermore, time trends in physical activity by educational levels and body mass index (BMI) categories were explored. Data were collected in independent cross‐sectional population surveys, implemented every 5 years from 1982 to 2012. The data comprised 21 903 men and 24 311 women. Participants underwent a health examination and filled in questionnaires. Information on LTPA, CPA, and OPA was used both separately and combined to create an index of total physical activity. Between 1982 and 2012, high LTPA has increased in men (from 21% to 33%) and women (from 12% to 27%). High CPA and high OPA have decreased in men (from 17% to 12% and from 48% to 36%, respectively) and women (from 30% to 20% and from 26% to 21%, respectively). Total physical activity has remained fairly stable. Differences by education and BMI have increased, particularly for LTPA. Marked changes in physical activity have taken place over time. Differences in LTPA and OPA have grown wider across educational groups and BMI categories.
Neuromuscular and athletic performance following core strength training in elite youth soccer: Role of instability
Authors: Prieske O. , Muehlbauer T. , Borde R. , Gube M. , Bruhn S. , Behm D. G. , Granacher U.
Published: January 2015

Cross‐sectional studies revealed that inclusion of unstable elements in core‐strengthening exercises produced increases in trunk muscle activity and thus potential extra stimuli to induce more pronounced performance enhancements in youth athletes. Thus, the purpose of the study was to investigate changes in neuromuscular and athletic performance following core strength training performed on unstable (CSTU) compared with stable surfaces (CSTS) in youth soccer players. Thirty‐nine male elite soccer players (age: 17 ± 1 years) were assigned to two groups performing a progressive core strength‐training program for 9 weeks (2–3 times/week) in addition to regular in‐season soccer training. CSTS group conducted core exercises on stable (i.e., floor, bench) and CSTU group on unstable (e.g., Thera‐Band® Stability Trainer, Togu© Swiss ball) surfaces. Measurements included tests for assessing trunk muscle strength/activation, countermovement jump height, sprint time, agility time, and kicking performance. Statistical analysis revealed significant main effects of test (pre vs post) for trunk extensor strength (5%, P < 0.05, d = 0.86), 10–20‐m sprint time (3%, P < 0.05, d = 2.56), and kicking performance (1%, P < 0.01, d = 1.28). No significant Group × test interactions were observed for any variable. In conclusion, trunk muscle strength, sprint, and kicking performance improved following CSTU and CSTS when conducted in combination with regular soccer training.
Movement and Agreement in Right‐Node‐Raising Constructions
Authors: Grosz Patrick Georg
Published: January 2015

This paper discusses the following type of right‐node‐raising construction (Ross): Coordinate structures in which elements that are interpreted in only one conjunct have moved across material that is interpreted as part of both conjuncts. I show that there are constructions of this type that simultaneously exhibit noncanonical plural agreement with two singularDPs and a ban on collective predicates in the same environment, which suggests contradictory conclusions. I argue that these properties follow from an approach to right‐node raising that allows multiple instances of sharing within the same tree (see Gračanin‐Yuksek,; de Vries). I propose an analysis of such plural agreement that treats it on analogy with agreement with conjoined singularDPs. I argue that, for the constructions with noncanonical plural agreement that I discuss, the present analysis is superior over a backward‐deletion analysis and a (non‐multidominance‐based) across‐the‐board movement analysis.
An Optimization Approach Toward a Robust Design of Six Degrees of Freedom Haptic Devices
Authors: Ahmad Aftab , Andersson Kjell , Sellgren Ulf
Published: January 2015

This work presents an optimization approach for the robust design of six degrees of freedom (DOF) haptic devices. Our objective is to find the optimal values for a set of design parameters that maximize the kinematic, dynamic, and kinetostatic performances of a 6-DOF haptic device while minimizing its sensitivity to variations in manufacturing tolerances. Because performance indices differ in magnitude, the formulation of an objective function for multicriteria performance requirements is complex. A new approach based on Monte Carlo simulation (MCS) was used to find the extreme values (minimum and maximum) of the performance indices to enable normalization of these indices. The optimization approach presented here is formulated as a methodology in which a hybrid design-optimization approach, combining genetic algorithm (GA) and MCS, is first used. This new approach can find the numerical values of the design parameters that are both optimal and robust (i.e., less sensitive to variation and thus to uncertainties in the design parameters). In the following step, with design optimization, a set of optimum tolerances is determined that minimizes manufacturing cost and also satisfies the allowed variations in the performance indices. The presented approach can thus enable the designer to evaluate trade-offs between allowed performance variations and tolerances cost.
Nonlinear Dynamics of Stockbridge Dampers
Authors: Barry O. , Zu J. W. , Oguamanam D. C. D.
Published: January 2015

The present paper deals with the nonlinear dynamics of a Stockbridge damper. The nonlinearity is from damping and the geometric stretching of the messenger. The Stockbridge damper is modeled as two cantilevered beams with tip masses. The equations of motion and boundary conditions are derived using Hamilton’s principle. The model is valid for both symmetric and asymmetric Stockbridge dampers. Explicit expressions are presented for the frequency equation, mode shapes, nonlinear frequency, and modulation equations. Experiments are conducted to validate the proposed model.
Development and Comparison of Laplace Domain Models for Nonslender Beams and Application to a Half-Car Model With Flexible Body
Authors: Michael Van Auken R.
Published: January 2015

Math models of flexible dynamic systems have been the subject of research and development for many years. One area of interest is exact Laplace domain solutions to the differential equations that describe the linear elastic deformation of idealized structures. These solutions can be compared to and complement finite order models such as state-space and finite element models. Halevi (2005, “Control of Flexible Structures Governed by the Wave Equation Using Infinite Dimensional Transfer Functions,” ASME J. Dyn. Syst., Meas., Control, 127(4), pp. 579–588) presented a Laplace domain solution for a finite length rod in torsion governed by a second-order wave equation. Van Auken (2012, “Development and Comparison of Laplace Domain and State-Space Models of a Half-Car With Flexible Body (ESDA2010–24518),” ASME J. Dyn. Syst., Meas., Control, 134(6), p. 061013) then used a similar approach to derive a Laplace domain solution for the transverse bending of an undamped uniform slender beam based on the fourth-order Euler–Bernoulli equation, where it was assumed that rotary inertia and shear effects were negligible. This paper presents a new exact Laplace domain solution to the Timoshenko model for an undamped uniform nonslender beam that accounts for rotary inertia and shear effects. Example models based on the exact Laplace domain solution are compared to finite element models and to slender beam models in order to illustrate the agreement and differences between the methods and models. The method is then applied to an example model of a half-car with a flexible body.
Combined Numerical and Experimental Investigation of the Cavitation Erosion Process
Authors: Jian Wang , Petkovšek Martin , Houlin Liu , Širok Brane , Dular Matevž
Published: January 2015

We are comparing results of numerical simulations against high-speed simultaneous observations of cavitation and cavitation erosion. We performed fully compressible, cavitating flow simulations to resolve the formation of the shock waves at cloud collapse—these are believed to be directly related to the formation of the damage. Good agreements were noticed between calculations and tests. Two high pressure peaks were found during one cavitation cycle. One relates to the cavitation collapse and the other one corresponds to the cavitation shed off, both contributing to a distinctive stepwise erosion damage growth pattern. Additional, more precise, simulations with much shorter time step were performed to investigate the processes of cavitation collapse and shedding off in more detail. There the importance of small cavitation structures which collapse independently of the main cloud was found. The present work shows a great potential for future development of techniques for accurate predictions of cavitation erosion by numerical means only.
Minority carrier lifetime of lattice-matched CdZnTe alloy grown on InSb substrates using molecular beam epitaxy
Authors: Liu Shi , Zhao Xin-Hao , Campbell Calli , DiNezza Michael J. , Zhao Yuan , Zhang Yong-Hang
Published: January 2015

A CdZnTe/MgCdTe double-heterostructure (DH) consisting of a 3 μm thick Cd0.9946Zn0.0054Te middle layer that is lattice-matched to an InSb substrate has been grown using molecular beam epitaxy. A long carrier lifetime of 3.4 × 102 ns has been demonstrated at room temperature, which is approximately three times as long as that of a CdTe/MgCdTe DH with identical layer thickness. This substantial improvement is due to the reduction in misfit dislocation density in the CdZnTe alloy. In contrast, a CdTe/MgCdTe DH with 3 μm thick CdTe layer grown on an InSb substrate exhibits a strain relaxation of ∼30%, which leads to a wider x-ray diffraction peak, a weaker integrated photoluminescence intensity, and a shorter minority carrier lifetime of 1.0 × 102 ns. These findings indicate that CdZnTe lattice-matched to InSb has great potential as applied to high-efficiency solar cells as well as virtual substrates for high-performance large-area HgCdTe focal plane arrays.
Comparative Proteomic Analysis Reveals Activation of Mucosal Innate Immune Signaling Pathways during Cholera
Authors: Ellis Crystal N. , LaRocque Regina C. , Uddin Taher , Krastins Bryan , Mayo-Smith Leslie M. , Sarracino David , Karlsson Elinor K. , Rahman Atiqur , Shirin Tahmina , Bhuiyan Taufiqur R. , Chowdhury Fahima , Khan Ashraful Islam , Ryan Edward T. , Calderwood Stephen B. , Qadri Firdausi , Harris Jason B.
Published: January 2015

Vibrio choleraeO1 is a major cause of acute watery diarrhea in over 50 countries. Evidence suggests thatV. choleraeO1 may activate inflammatory pathways, and a recent study of a Bangladeshi population showed that variants in innate immune genes play a role in mediating susceptibility to cholera. We analyzed human proteins present in the small intestine of patients infected withV. choleraeO1 to characterize the host response to this pathogen. We collected duodenal biopsy specimens from patients with acute cholera after stabilization and again 30 days after initial presentation. Peptides extracted from biopsy specimens were sequenced and quantified using label-free mass spectrometry and SEQUEST. Twenty-seven host proteins were differentially abundant between the acute and convalescent stages of infection; the majority of these have known roles in innate defense, cytokine production, and apoptosis. Immunostaining confirmed that two proteins, WARS and S100A8, were more abundant in lamina propria cells during the acute stage of cholera. Analysis of the differentially abundant proteins revealed the activation of key regulators of inflammation by the innate immune system, including Toll-like receptor 4, nuclear factor kappa-light-chain-enhancer of activated B cells, mitogen-activated protein kinases, and caspase-dependent inflammasomes. Interleukin-12β (IL-12β) was a regulator of several proteins that were activated during cholera, and we confirmed that IL-12β was produced by lymphocytes recovered from duodenal biopsy specimens of cholera patients. Our study shows that a broad inflammatory response is generated in the gut early after onset of cholera, which may be critical in the development of long-term mucosal immunity againstV. choleraeO1.
Natural Variant of Collagen-Like Protein A in Serotype M3 Group A Streptococcus Increases Adherence and Decreases Invasive Potential
Authors: Flores Anthony R. , Jewell Brittany E. , Versalovic Erika M. , Olsen Randall J. , Bachert Beth A. , Lukomski Slawomir , Musser James M.
Published: January 2015

Group A
Streptococcus
(GAS) predominantly exists as a colonizer of the human oropharynx that occasionally breaches epithelial barriers to cause invasive diseases. Despite the frequency of GAS carriage, few investigations into the contributory molecular mechanisms exist. To this end, we identified a naturally occurring polymorphism in the gene encoding the streptococcal collagen-like protein A (SclA) in GAS carrier strains. All previously sequenced invasive serotype M3 GAS possess a premature stop codon in the
sclA
gene truncating the protein. The carrier polymorphism is predicted to restore SclA function and was infrequently identified by targeted DNA sequencing in invasive strains of the same serotype. We demonstrate that a strain with the carrier
sclA
allele expressed a full-length SclA protein, while the strain with the invasive
sclA
allele expressed a truncated variant. An isoallelic mutant invasive strain with the carrier
sclA
allele exhibited decreased virulence in a mouse model of invasive disease and decreased multiplication in human blood. Further, the isoallelic invasive strain with the carrier
sclA
allele persisted in the mouse nasopharynx and had increased adherence to cultured epithelial cells. Repair of the premature stop codon in the invasive
sclA
allele restored the ability to bind the extracellular matrix proteins laminin and cellular fibronectin. These data demonstrate that a mutation in GAS carrier strains increases adherence and decreases virulence and suggest selection against increased adherence in GAS invasive isolates.
The Secreted Effector Protein EspZ Is Essential for Virulence of Rabbit Enteropathogenic Escherichia coli
Authors: Wilbur John Scott , Byrd Wyatt , Ramamurthy Shylaja , Ledvina Hannah E. , Khirfan Khaldoon , Riggs Michael W. , Boedeker Edgar C. , Vedantam Gayatri , Viswanathan V. K.
Published: January 2015

Attaching and effacing (A/E) pathogens adhere intimately to intestinal enterocytes and efface brush border microvilli. A key virulence strategy of A/E pathogens is the type III secretion system (T3SS)-mediated delivery of effector proteins into host cells. The secreted protein EspZ is postulated to promote enterocyte survival by regulating the T3SS and/or by modulating epithelial signaling pathways. To explore the role of EspZ in A/E pathogen virulence, we generated an isogenic
espZ
deletion strain (Δ
espZ
) and corresponding
cis
-complemented derivatives of rabbit enteropathogenic
Escherichia coli
and compared their abilities to regulate the T3SS and influence host cell survival
in vitro
. For virulence studies, rabbits infected with these strains were monitored for bacterial colonization, clinical signs, and intestinal tissue alterations. Consistent with data from previous reports,
espZ
-transfected epithelial cells were refractory to infection-dependent effector translocation. Also, the Δ
espZ
strain induced greater host cell death than did the parent and complemented strains. In rabbit infections, fecal Δ
espZ
strain levels were 10-fold lower than those of the parent strain at 1 day postinfection, while the complemented strain was recovered at intermediate levels. In contrast to the parent and complemented mutants, Δ
espZ
mutant fecal carriage progressively decreased on subsequent days. Δ
espZ
mutant-infected animals gained weight steadily over the infection period, failed to show characteristic disease symptoms, and displayed minimal infection-induced histological alterations. Terminal deoxynucleotidyltransferase-mediated dUTP-biotin nick end labeling (TUNEL) staining of intestinal sections revealed increased epithelial cell apoptosis on day 1 after infection with the Δ
espZ
strain compared to animals infected with the parent or complemented strains. Thus, EspZ-dependent host cell cytoprotection likely prevents epithelial cell death and sloughing and thereby promotes bacterial colonization.
Cyclo(Phe-Pro) Produced by the Human Pathogen Vibrio vulnificus Inhibits Host Innate Immune Responses through the NF-κB Pathway
Authors: Kim Kiwan , Kim Na-Jeong , Kim So Young , Kim In Hwang , Kim Kun-Soo , Lee Gap Ryol
Published: January 2015

Cyclo(Phe-Pro) (cFP) is a secondary metabolite produced by certain bacteria and fungi. Although recent studies highlight the role of cFP in cell-to-cell communication by bacteria, its role in the context of the host immune response is poorly understood. In this study, we investigated the role of cFP produced by the human pathogen
Vibrio vulnificus
in the modulation of innate immune responses toward the pathogen. cFP suppressed the production of proinflammatory cytokines, nitric oxide, and reactive oxygen species in a lipopolysaccharide (LPS)-stimulated monocyte/macrophage cell line and in bone marrow-derived macrophages. Specifically, cFP inhibited inhibitory κB (IκB) kinase (IKK) phosphorylation, IκBα degradation, and nuclear factor κB (NF-κB) translocation to the cell nucleus, indicating that cFP affects the NF-κB pathway. We searched for genes that are responsible for cFP production in
V. vulnificus
and identified VVMO6_03017 as a causative gene. A deletion of VVMO6_03017 diminished cFP production and decreased virulence in subcutaneously inoculated mice. In summary, cFP produced by
V. vulnificus
actively suppresses the innate immune responses of the host, thereby facilitating its survival and propagation in the host environment.
A Metalloprotease Secreted by the Type II Secretion System Links Vibrio cholerae with Collagen
Authors: Park Bo R. , Zielke Ryszard A. , Wierzbicki Igor H. , Mitchell Kristie C. , Withey Jeffrey H. , Sikora Aleksandra E.
Published: January 2015

Vibrio cholerae
is autochthonous to various aquatic niches and is the etiological agent of the life-threatening diarrheal disease cholera. The persistence of
V. cholerae
in natural habitats is a crucial factor in the epidemiology of cholera. In contrast to the well-studied
V. cholerae
-chitin connection, scarce information is available about the factors employed by the bacteria for the interaction with collagens. Collagens might serve as biologically relevant substrates, because they are the most abundant protein constituents of metazoan tissues and
V. cholerae
has been identified in association with invertebrate and vertebrate marine animals, as well as in a benthic zone of the ocean where organic matter, including collagens, accumulates. Here, we describe the characterization of the
V. cholerae
putative collagenase, VchC, encoded by open reading frame VC1650 and belonging to the subfamily M9A peptidases. Our studies demonstrate that VchC is an extracellular collagenase degrading native type I collagen of fish and mammalian origin. Alteration of the predicted catalytic residues coordinating zinc ions completely abolished the protein enzymatic activity but did not affect the translocation of the protease by the type II secretion pathway into the extracellular milieu. We also show that the protease undergoes a maturation process with the aid of a secreted factor(s). Finally, we propose that
V. cholerae
is a collagenovorous bacterium, as it is able to utilize collagen as a sole nutrient source. This study initiates new lines of investigations aiming to uncover the structural and functional components of the
V. cholerae
collagen utilization program.
Biosynthesis of Cell Envelope-Associated Phenolic Glycolipids in Mycobacterium marinum
Authors: Vergnolle Olivia , Chavadi Sivagami Sundaram , Edupuganti Uthamaphani R. , Mohandas Poornima , Chan Catherine , Zeng Julie , Kopylov Mykhailo , Angelo Nicholas G. , Warren J. David , Soll Clifford E. , Quadri Luis E. N.
Published: January 2015

Phenolic glycolipids (PGLs) are polyketide synthase-derived glycolipids unique to pathogenic mycobacteria. PGLs are found in several clinically relevant species, including various
Mycobacterium tuberculosis
strains,
Mycobacterium leprae
, and several nontuberculous mycobacterial pathogens, such as
M. marinum
. Multiple lines of investigation implicate PGLs in virulence, thus underscoring the relevance of a deep understanding of PGL biosynthesis. We report mutational and biochemical studies that interrogate the mechanism by which PGL biosynthetic intermediates (
p
-hydroxyphenylalkanoates) synthesized by the iterative polyketide synthase Pks15/1 are transferred to the noniterative polyketide synthase PpsA for acyl chain extension in
M. marinum
. Our findings support a model in which the transfer of the intermediates is dependent on a
p
-hydroxyphenylalkanoyl-AMP ligase (FadD29) acting as an intermediary between the iterative and the noniterative synthase systems. Our results also establish the
p
-hydroxyphenylalkanoate extension ability of PpsA, the first-acting enzyme of a multisubunit noniterative polyketide synthase system. Notably, this noniterative system is also loaded with fatty acids by a specific fatty acyl-AMP ligase (FadD26) for biosynthesis of phthiocerol dimycocerosates (PDIMs), which are nonglycosylated lipids structurally related to PGLs. To our knowledge, the partially overlapping PGL and PDIM biosynthetic pathways provide the first example of two distinct, pathway-dedicated acyl-AMP ligases loading the same type I polyketide synthase system with two alternate starter units to produce two structurally different families of metabolites. The studies reported here advance our understanding of the biosynthesis of an important group of mycobacterial glycolipids.
Absence of a Functional erm Gene in Isolates of Mycobacterium immunogenum and the Mycobacterium mucogenicum Group, Based on
In Vitro
Clarithromycin Susceptibility
Authors: Brown-Elliott Barbara A. , Hanson Kimberly , Vasireddy Sruthi , Iakhiaeva Elena , Nash Kevin A. , Vasireddy Ravikiran , Parodi Nicholas , Smith Terry , Gee Martha , Strong Anita , Barker Adam , Cohen Samuel , Muir Haleina , Slechta E. Susan , Wallace Richard J.
Published: January 2015

Macrolide resistance has been linked to the presence of a functional erythromycin ribosomal methylase (
erm
) gene in most species of pathogenic rapidly growing mycobacteria (RGM). For these
Mycobacterium
isolates, extended incubation in clarithromycin is necessary to determine macrolide susceptibility. In contrast, the absence of a detectable
erm
gene in isolates of
M. chelonae
,
M. senegalense
, and
M. peregrinum
and a nonfunctional
erm
gene in
M. abscessus
subsp.
massiliense
and 15% to 20% of
M. abscessus
subsp.
abscessus
isolates renders these species intrinsically macrolide susceptible. Not all RGM species have been screened for the presence of an
erm
gene, including the
Mycobacterium mucogenicum
group (
M. mucogenicum
,
M. phocaicum
, and
M. aubagnense
) and
Mycobacterium immunogenum
. A total of 356 isolates of these two pathogenic RGM taxa from two reference laboratories (A.R.U.P. Reference Laboratories and the Mycobacteria/Nocardia Laboratory at the University of Texas Health Science Center at Tyler) underwent clarithromycin susceptibility testing with readings at 3 to 5 days and 14 days. Only 13 of the 356 isolates had resistant clarithromycin MICs at initial extended MIC readings, and repeat values on all available isolates were ≤2 μg/ml. These studies suggest that these two additional RGM groups do not harbor functional
erm
genes and, like
M. chelonae
, do not require extended clarithromycin susceptibility testing. We propose to the Clinical Laboratory and Standards Institute that isolates belonging to these above-mentioned six rapidly growing mycobacterial groups based on molecular identification with no known functional
erm
genes undergo only 3 to 5 days of susceptibility testing (to exclude mutational resistance).
Histiocytic necrotising lymphadenitis (Kikuchi-Fujimoto disease) of axillary lymph nodes
Authors: Nagaraju Santosh , Vaishnav Sakshi , Burke Leandra H , Norman Earl M
Published: January 2015

Kikuchi-Fujimoto disease (KFD) or histiocytic necrotising lymphadenitis is a rare entity, occurring most commonly in young Asian adults. KFD is characterised by fever with tender lymph node enlargement. The cervical group of lymph nodes is most commonly involved, and the diagnosis is conclusively made by lymph node biopsy and histopathology. KFD is a self-limiting condition, which usually resolves over 1–4 months. Symptomatic treatment with antipyretics and/or non-steroidal anti-inflammatory drugs is recommended. Here we describe an uncommon presentation of KFD in a young woman in which only the axillary lymph nodes were enlarged.
Achalasia: a risk factor that must not be forgotten for esophageal squamous cell carcinoma
Authors: Ríos-Galvez Shareni , Meixueiro-Daza Arturo , Remes-Troche Jose Maria
Published: January 2015

Alcohol and tobacco abuse are the main risk factors for esophageal squamous cell carcinoma (ESCC), but other conditions that induce chronic irritation of the esophageal mucosa have also been attributed to it. For example, long-standing achalasia increases 16 times the risk of developing ESCC. We report the case of a patient with long-standing achalasia who developed ESCC. Although this complication is infrequent, it should be remembered by clinicians who treat patients with achalasia to detect early stages cancer.
Acute unilateral isolated ptosis
Authors: Court Jennifer Helen , Janicek David
Published: January 2015

A 64-year-old man presented with a 2-day history of acute onset painless left ptosis. He had no other symptoms; importantly pupils were equal and reactive and eye movements were full. There was no palpable mass or swelling. He was systemically well with no headache, other focal neurological signs, or symptoms of fatigue. CT imaging showed swelling of the levator palpebrae superioris suggestive of myositis. After showing no improvement over 5 days the patient started oral prednisolone 30 mg reducing over 12 weeks. The ptosis resolved quickly and the patient remains symptom free at 6 months follow-up. Acute ptosis may indicate serious pathology. Differential diagnoses include a posterior communicating artery aneurysm causing a partial or complete third nerve palsy, Horner’s syndrome, and myasthenia gravis. A careful history and examination must be taken. Orbital myositis typically involves the extraocular muscles causing pain and diplopia. Isolated levator myositis is rare.
Improving patient flow in pre-operative assessment
Authors: Stark Cameron , Gent Anne , Kirkland Linda
Published: January 2015

Annual patient attendances at a pre-operative assessment department increased by 24.8% from 5659 in 2009, to 7062 in 2012. The unit was staffed by administrative staff, nurses, and health care assistants (HCA). Medical review was accessed via on call medical staff, or notes were sent to anaesthetists for further review.

With rising demand, patient waits increased. The average lead time for a patient (time from entering the department to leaving) was 79 minutes. 9.3% of patients attended within two weeks of their scheduled surgery date. 10% of patients were asked to return on a later day, as there was not sufficient capacity to undertake their assessment. There were nine routes of referral in to the department.

Patients moved between different clinic rooms and the waiting area several times. Work patterns were uneven, as many attendances were from out-patient clinics which meant peak attendance times were linked to clinic times. There were substantial differences in the approaches of different nurses, making the HCA role difficult. Patients reported dissatisfaction with waits.

Using a Lean quality improvement process with rapid PDSA cycles, the service changed to one in which patients were placed in a room, and remained there for the duration of their assessment. Standard work was developed for HCWs and nurses. Rooms were standardised using 5S processes, and set up improved to reduce time spent looking for supplies. A co-ordinator role was introduced using existing staff to monitor flow and to organise the required medical assessments and ECGs. Timing of booked appointments were altered to take account of clinic times. Routes in to the department were reduced from nine to one.

Ten months after the work began, the average lead time had reduced to 59 minutes. The proportion of people attending within two weeks of their surgery decreased from 9.3% to 5.3%. Referrals for an anaesthetic opinion decreased from 30% to 20%, and in the month reviewed no one had to return to be seen as a result of limited capacity.
Traffic lights: putting a stop to unsafe patient transfers
Authors: Parbhoo Anita , Batte Jemma
Published: January 2015

Poor handover between doctors is a recognised cause of error in hospitals.[1] Watford General Hospital is a busy acute trust in southern England, where high admission rates necessitate timely patient transfers from the acute admissions unit (AAU) to the medical wards. We found that doctors were infrequently informed of patient transfers, and they rarely handed over patient care when a patient was moved. Our aim was to minimise preventable harm to patients by prompting handover of clinically unstable patients, and patients with outstanding investigations or referrals, at the time of transfer. We introduced a traffic light tool to categorise patients on the medical take as red, amber, or green according to their clinical status at time of admission to AAU. The traffic light colour, which was assigned both on paper and electronically, was designed to prompt a verbal handover between doctors at the time of patient transfer from AAU.
Monitoring the freeze-up and ice cover progression of the Slave River
Authors: Das Apurba , Sagin Jay , Van der Sanden Joost , Evans Earl , McKay Henry , Lindenschmidt Karl-Erich
Published: January 2015

River ice is an important component to maintain traditional and cultural lifestyles for the peoples along the Slave River in the Northwest Territories. During the winter a stable ice cover provides a vital transportation link to hunting, trapping, and fishing areas along the river. However, little was known about the Slave River ice cover characteristics and behaviour during the freeze-up and ice cover progression period. RADARSAT-2 satellite and time-lapse camera imagery were used in this study to document the different types of ice and understand the mechanisms of ice cover formation progression along the river during the course of winter. Time-lapse images were analyzed to observe the frazil ice generation and patterns of stable ice cover formation of the Slave River near Fort Smith during freeze-up. RADARSAT-2 images acquired from the Slave River Delta areas captured ice cover flooding due to higher river flows in mid-winter. Field surveys along the river provided insights about the ice cover growth in various sections along the river. Air pockets and layers under the ice cover were also detected during the ice surveys. The variation of water flows during the winter has a great impact on the Slave River ice regime. Increases in discharge cause the ice cover to crack or dislodge from the river banks leading to water seeping onto the ice and flooding it, which has implications for muskrat and beaver populations.
Three-dimensional unified geological model of the Milk River Transboundary Aquifer (Alberta, Canada – Montana, USA)
Authors: Pétré Marie-Amélie , Rivera Alfonso , Lefebvre René
Published: January 2015

The Milk River Transboundary Aquifer (Canada–USA) has been so intensively used over the 20th century that concerns have risen about the durability of this resource since the mid-1950s. This aquifer actually corresponds to the middle Virgelle Member of the Upper Cretaceous Milk River Formation (called Eagle Formation in Montana). To assess the conditions needed for a sustainable use of the aquifer, a comprehensive and unified portrait of the aquifer is needed across its international boundary. The stratigraphic framework and geometry of geological units on both sides of the international border were thus unified in a 50 000 km2three-dimensional (3D) geological model. The Virgelle Member is 0–60 m thick and it subcrops near the border and along both sides of the Sweetgrass Arch. It dips away from the subcrop areas in a semi-radial pattern. The Medicine Hat gas field hosted by the Alderson Member (Alberta), which is separated from the other members by a regional unconformity, and the Tiger Ridge gas field near the Bears Paw Mountains (Montana) limit the extent of the aquifer. The unified 3D geological model forms the necessary basis for conceptual and numerical hydrogeological models of the Milk River Aquifer.
Investigation of regional seismicity before and after hydraulic fracturing in the Horn River Basin, northeast British Columbia
Authors: Farahbod Amir Mansour , Kao Honn , Walker Dan M. , Cassidy John F.
Published: January 2015

We systematically re-analyzed historical seismograms to verify the existence of background seismicity in the Horn River Basin of northeast British Columbia before the start of regional shale gas development. We also carefully relocated local earthquakes that occurred between December 2006 and December 2011 to delineate their spatiotemporal relationship with hydraulic fracturing (HF) operations in the region. Scattered seismic events were detected in the Horn River Basin throughout the study periods. The located seismicity within 100 km of the Fort Nelson seismic station had a clearly increasing trend, specifically in the Etsho area where most local HF operations were performed. The number of events was increased from 24 in 2002–2003 (prior to HF operations) to 131 in 2011 (peak period of HF operations). In addition, maximum magnitude of the events was shifted from ML2.9 to ML3.6 as the scale of HF operation expanded from 2006–2007 to 2011. Based on our relocated earthquake catalog, the overall b value is estimated at 1.21, which is higher than the average of tectonic/natural earthquakes of ∼1.0. Our observations highly support the likelihood of a physical relationship between HF operation and induced seismicity in the Horn River Basin. Unfortunately, due to the sparse station density in the region, depth resolution is poor for the vast majority of events in our study area. As new seismograph stations are established in northeast British Columbia, both epicentral mislocation and depth uncertainty for future events are expected to improve significantly.
When “data” are not data: the pitfalls of post hoc analyses that use stock assessment model output
Authors: Brooks Elizabeth N. , Deroba Jonathan J.
Published: January 2015

The practice of treating stock assessment model output as data in subsequent modeling efforts is becoming more common, aided in part by the growing availability of online repositories of assessment results (misleadingly referred to as “data” bases). Such modeling exercises frequently overlook the uncertainty in the assessment output, the potential bias in estimates and correlation between estimates, and the structural assumptions of the original assessment model. We provide examples of post hoc analyses and discuss the problems in each case. We suggest alternative approaches that could have avoided using assessment model output altogether or suggest analyses that may have exposed the pitfalls of such methods. Whenever possible, we suggest not using stock assessment model output as data in post hoc analyses. If using assessment model output as data is unavoidable, then to address some aspects of the uncertainties associated with using assessment model estimates, we suggest collaborating with lead assessment scientists, sensitivity analyses, errors-in-variables methods, and cross-validation methods. Such additional work is imperative if research that uses stock assessment output as data is to make robust and meaningful contributions to stock assessment methodology and management decisions.