bluuebunny/crossref_metadata_2025 huggingface dataset:
Image Processing and Localization for Detecting and Tracking Wildland Fires
Authors: Sathyan Anoop , Kumar Manish , Cohen Kelly
Published: January 2016

Unmanned Aerial Vehicles (UAVs) are being used for a wide variety of applications including detecting and tracking wildland fires. Using UAVs for fire-fighting purposes reduces the human involvement for this high risk job. Such a mission involves locating the wildland fire, tracking the direction of spread of the fire and searching for human presence in the region. This paper investigates the algorithmic development for the use of UAVs to detect and track wildland fires. This would involve using the fuzzy toolbox in MATLAB along with MICRODEM, a software which provides the Digital Elevation Model (DEM) for the region. The objective of this research is to accomplish the following: 1) use genetic fuzzy based image processing tools to identify fire from the video feed obtained from the camera attached to the UAV in real time 2) look for human presence in the region and 3) estimate the location of the fire based on the geological data available for the region.
Trust-Based Optimal Subtask Allocation and Model Predictive Control for Human-Robot Collaborative Assembly in Manufacturing
Authors: Rahman S. M. Mizanoor , Sadrfaridpour Behzad , Wang Yue
Published: January 2016

We develop a one human-one robot hybrid cell for collaborative assembly in manufacturing. The selected task is to assemble a few LEGO parts into a final assembled product following specified instructions and sequence in collaboration between the human and the robot. We develop a two-level feedforward optimization strategy that determines the optimal subtask allocation between the human and the robot for the selected assembly before the assembly starts. We derive dynamics models for human’s trust in the robot and the robot’s trust in the human for the assembly and estimate the trusts. The aim is to maintain satisfactory trust levels between the human and the robot through the application of the optimal subtask allocation. Again, subtask re-allocation is proposed to regain trusts if the trusts reduce to below the specified levels. Furthermore, it is hypothesized that fluctuations in human’s trust in the robot may cause fluctuations in human’s speeds and the human may appreciate if the robot adjusts its speeds with changes in human speeds. Hence, trust-based Model Predictive Control (MPC) is proposed to minimize the variations between human and robot speeds and to maximize the trusts. Experiment results prove the effectiveness of the hybrid cell, the feedforward optimal subtask allocation and of the trust-based MPC. The results also show that the overall assembly performance can be enhanced and the performance status can be monitored through a single dynamic parameter, i.e. the trust.
Performance Evaluation of Two Nonlinear Controllers on an Attitude System Using SGCMG
Authors: Nuñez Gamboa Juan Sebastian , López Juan David
Published: January 2016

This paper deals with the modeling and simulation of an attitude control system composed of three Single Gimbal Control Moment Gyroscopes (SGCMG) in a pyramidal configuration using two nonlinear controllers. The first controller is a first-order sliding mode which is robust to bounded uncertainties such as modeling simplifications, sensor noise and external disturbances, but it causes high frequency input, which can exceed the limit of the power systems. To overcome the drawback of the sliding mode, an I&I adaptive control is proposed. This controller estimates unknown parameters by introducing new states, resulting in smaller input gains and frequencies. At first, the dynamic model of SGCMG and the dynamic model of the attitude system were constructed. Based on this model, the steering laws of the SGCMG’s for the two nonlinear controllers were designed. The simulation of the attitude control system is implemented in MATLAB. The simulation results show the effectiveness and the advantages of the proposed controllers.
Meal Detection and Meal Size Estimation for Type 1 Diabetes Treatment: A Variable State Dimension Approach
Authors: Xie Jinyu , Wang Qian
Published: January 2016

To compensate the glucose variability caused by meals is essential in developing Artificial Pancreas for type 1 diabetes. Most existing algorithms rely on meal announcements and determine the insulin doses based on an Insulin-to-Carbohydrate ratio (I:C ratio). However, patients, especially young patients, often forget to provide meal information under natural living conditions. A Variable State Dimension (VSD) based algorithm is developed to detect meals which are unknown to the controller (unannounced meals). The algorithm is evaluated using an FDA-approved UVa/Padova simulator and has demonstrated to achieve 95% success rate in meal detection with less than 17% false alarm rate. In addition, the average meal size estimation error is no more than 13%. We then integrate the VSD-based meal detection and estimation algorithm with our previous published glucose dynamics model consisting of both insulin and carbohydrate inputs. The goodness of fit for 30min-ahead glucose predictions using meal information provided by the VSD-based algorithm has increased by 86% in average compared to the prediction using a model without meal input based on plasma blood glucose (BG) data. Simulation results also show that compared to several meal detection/estimation algorithms in the literature, the VSD-based algorithm has comparable or shorter detection time.
Health-Aware and User-Involved Battery Charging Management for Electric Vehicles Using Linear Quadratic Control
Authors: Fang Huazhen , Wang Yebin
Published: January 2016

This paper studies control-theory-enabled charging management for battery systems in electric vehicles (EVs). Charging is a crucial factor for the battery performance and life as well as EV users’ anxiety. Existing methods run with two shortcomings: insufficiency of battery health awareness during charging, and failure to include the user into the charging loop. To address such issues, we propose to perform charging that deals with both health protection and user-specified charging needs or objectives. Capitalizing on the linear quadratic control theory, a set of charging strategies are developed. A simulation-based study demonstrates their effectiveness and potential. We expect that charging with health awareness and user involvement will improve not only the battery longevity but also user satisfaction.
A Uniform Control for Tracking and Point Stabilization of Differential Drive Robots Subject to Hard Input Constraints
Authors: Zeiaee Amin , Soltani-Zarrin Rana , Jayasuriya Suhada , Langari Reza
Published: January 2016

This paper develops a unified framework for point stabilization and tracking control of differential drive robots under hard input constraints. The proposed control strategy is based on the recently introduced Pointwise Angle Minimization method and addresses the steering problem by studying a robot’s achievable directions of motion considering the constraints imposed on it. To illustrate the strength of the proposed framework, a new control problem which combines the posture stabilization and tracking control is studied. The problem of interest is steering a constrained-input mobile robot from an initial point towards a final point on a desired trajectory while regulating the robot’s heading such that the control convergence is guaranteed within the admissible input space. Inspired by the geometry of sliding mode control, this paper proposes a new control strategy for this problem. The stability of the closed loop system under the proposed steering scheme is proved by Lyapunov analysis for the shortest path trajectory and generalization to the case of arbitrarily chosen desired trajectory has been proposed. Finally, effectiveness of the discussed control strategies are illustrated by several simulation results.
Task-Allocation and Control of a Ground Robots Collective for Warehouse Automation
Authors: Guney Mehmet Ali , Raptis Ioannis
Published: January 2016

In the last years, there have been several attempts to deploy Autonomous Guided Vehicles (AGVs) to automate the operation of warehouse environments. The implementation of AGVs has numerous advantages over conventional warehouse automation systems in terms of cost and scalability. In this work, we present the development of a test-bed platform for the utilization of an AGV collective to a warehouse automation system. The system architecture has plug-and-play algorithmic design which makes it extremely modular. In this system, small-scale robotic forklifts are used to transport an arbitrary number of circular pallets to predefined locations. The forklift robots are able to move in the arena without colliding each other due to the implementation of a centralized deconfliction algorithm. A task allocation algorithm prevents the forklift drives from being trapped by a fence of pallets. The performance of the proposed system is validated by both simulation and experimental results.
Use of Geometric In-Line Inspection (ILI) Intelligence Tools With the Inertial Module for Diagnosis and Management of Structural Integrity in Pipelines With Geohazards: Case Study
Authors: Hernández Sánchez Jon Freddy , Vergara Carlos Antonio , Hidalgo Carlos
Published: January 2016

Colombia is a country located in a geographical area with great geological diversity, where every day the effects of climate change increases the probability of the failure of buried pipelines due to the movement of land or the instability associated with them. That is why the use of geometric In Line Inspection (ILI) intelligent tools with the inertial module is important for the diagnosis of structural integrity of pipelines and is associated with an integrity management program due to the geotechnical threats present throughout its path. It decreases maintenance costs due to pump stoppage for unscheduled repairs, anticipating the solution, and mitigating and controlling deformations in the pipeline caused by geotechnical ground displacements.

OCENSA-Pipeline Central SA (Colombia) has developed, through its experience, a program to manage integrity by determining the structural expense in specific sections due to displacement of the pipeline caused by ground movement through the use of the Geometric ILI tools and MFL inertial module. This paper specifically presents the use of the tool in decision-making based on OCENSA’s preset study limits for deformations in the elastic range and plastic building material of the pipeline.

In 1997 OCENSA was among the first companies in Latin America to use Inertial Geo-positioning technology; today there are sectors which have been inspected with this technology as many as five times, in which pipe displacement of up to 5 meters has been found.

The case study presented refers to a geographical point on the route of the pipeline located in the Andes, at the site of the movement known as the “La negra” ravine, near the town of Puente Nacional, where movements of the pipeline associated with geotechnically unstable slope conditions were detected by In line inspection (ILI) Geometric and inertial modules, beginning in 2004. Since that time, integrity management was conducted in order to reduce the chances pipeline failure will materialize in this area of geotechnical instability.
Identification and Monitoring of Geotechnical Risk Areas Using Inertial Data Supplied by In-Line Inspection Tools
Authors: Castro Tom Henry Bernabe , Moya John Erick Malpartida
Published: January 2016

By their nature, Pipeline Transmission Systems are exposed to threats from various sources. These include the threat of Weather and Outside Forces (WOF), this threat has a destructive potential associated with landslides, creeping, soil erosion and scouring in rivers, etc. Their hazards increase when pipelines are installed in areas with a tropical climate, having rains of a magnitude that often tend to destabilize the soil surrounding the pipelines, affecting its integrity and therefore the safety of people and the environment.

The identification and monitoring of geotechnical risk areas, using inertial data, is based on the reprocessing and analysis of the raw data provided by in line inspection tools. The result of this analysis, after the noise reduction process using a variety of filters at different intervals, reveals areas where there is possible deformation. These zones are transformed into indications that are studied by an analyst, correlating other data sources such as terrain topography, soil characteristics, hydrology, ground motion records, ILI records (caliper records, MFL records, etc.), as-built data, stress concentrators, etc. The analyst determines if they are pipeline deformations due to soil movement or if the indication is caused by another source such as the noise caused by the electronic components of the tool, the operating conditions during the inspection, the filtering process, etc.

Areas with signs of strain are evaluated to determine the tensional state in critical conditions for each specific case. If the stresses are close to the limits, a field inspection and an action plan are needed for each case. In certain cases, according to the experts, field indications are evaluated to verify the data obtained by the ILI Tool and to simultaneously give feedback to the noise reduction process.

The execution of the calculation process allows the monitoring and identification of geotechnical risk areas, providing better control over parameters such as limits for reporting indications, control of discrimination and selection criteria, detailed assessment of each indication, etc. Finally, this process provides the opportunity to obtain additional information from the ILI inspection such as unregistered bending, misaligned welds, areas with excess root welding, etc.
Redundancy in the Analysis of Information, Applied to the Early Identification of Effects on Pipelines Subjected to External Loads: Case Study
Authors: Aristizabal Ceballos Jaime , Eliecer Torres Camilo , Acosta Cubillos Javier Alexander , Cuevas Henry Osorio , Galvis Adriana , Gualdrón Oscar , Trespalacios Prada Diego
Published: January 2016

The principle of redundancy in the analysis of pipeline integrity has taken on particular significance in recent years, thanks to the integration and relating of information obtained from various sources, which include, smart pig runs, visual right-of-way inspections and monitoring of the land and the pipeline. This document contains information related to the monitoring and analysis prior to emergency actions taken in the case study presented, located in northeast Colombia, where the effects of mining activity and excess rain during the winter period of 2010–2011 combined.

The integrity information available with regard to background, visual right-of-way inspection, threat and risk assessments, direct monitoring of the pipeline and the analysis of deformation by bending, which Ecopetrol’s Office of Vice-president for Transportation and Logistics (VIT) made at the site, was taken into account. In addition, it includes a description of the interrelationship of such information, the findings in the activities conducted during the attention to the site, for the purpose of identifying the evidence related to external loads exerted by the land in the soil-pipeline interaction, which made it possible to better determine the proposed plan of action.

The redundancy in the analysis of this information makes it possible to more accurately determine the root cause of the problem, the interaction between the phenomenon (external load - geotechnical event) and the pipeline, by which attention was directed in the field and action plans were obtained that better mitigate the threat and guarantee more safe and reliable operation.
Panorama of the Strategy for Managing the Risk Created by the Weather-Related and Outside Force Threat in VIT-Ecopetrol
Authors: Aristizábal Ceballos Jaime Hernán , Chaves Agudelo Julián Fernando
Published: January 2016

The realization of the weather-related and outside force threat has historically caused losses of containment with their subsequent social, environmental, economic and image consequences for Ecopetrol. The zones in which these phenomena occur are characterized by the interaction of transmission systems with an environment that is complex in its topographical, geological-geomorphological and climatic conditions, and because of the anthropic impact of changes in land use.

In Ecopetrol’s office of the Vice-president for Transportation Logistics (VIT-Ecopetrol), a threat management strategy has been proposed that seeks to minimize the vulnerability of the pipelines to processes that can impact on operating efficiency or that, because of their degree of complexity, require comprehensive management in order to guarantee operation at tolerable levels of risk. This article presents a panorama of the work performed with regard to the validation of the threat and risk levels of the assets, the internal analyses performed by geotechnical professionals for formulating the plans for the management of assets and the accompaniment of such in order to achieve the continuous operation of the transmission systems.
Landslide and Emergencial Works in Transpetro Right-of-Way
Authors: Oliveira Hudson Régis , Cordeiro Guilherme Licodiedoff , Langone Marcelo Julio , de Paula Henrique Xavier
Published: January 2016

Several natural disasters involving mass movements have occurred in Santa Catarina and Brazil. One of these caused a large number of fatalities, social and economic damage were those that occurred in the middle valley of the Itajaí River in November 2008. However, landslides continue to occur and provisions should be adopted. This paper aims to describe the contingency actions during emergency works related to a landslide, which occurred at a slope besides BR-376 Highway (Guaratuba / PR) and Transpetro right-of-way in March 2011. The landslide affected the highway concessionaire and Transpetro operations. This site was stabilized by emergency works, including an anchored wall, which is shown and described in the work. This paper records the emergency works taken and lessons learned.
Elementary Classroom Teachers’ Beliefs Across Time: Learning to Teach Physical Education
Authors: Chróinín Déirdre Ní , O’Sullivan Mary
Published: January 2016

This longitudinal research explored beginning elementary classroom teachers’ beliefs about learning to teach physical education (PE) across time. Understanding how beliefs shape the process of learning to teach PE can inform the design of more impactful physical education teacher education (PETE). We mapped beliefs over six years including the three years of an undergraduate elementary teacher education program and the first three years teaching in schools through reflective writing tasks and semistructured interviews. Across time these beginning teachers believed that learning to teach PE required active participation in PE content, building of a resource bank of content ideas, and practice of teaching the content. Building competence in PE content through active participation combined with development of more complex understandings of PE content through PETE pedagogies can better support elementary teachers learning to teach PE.
Coordinate actions of innate immune responses oppose those of the adaptive immune system during
Salmonella
infection of mice
Authors: Hotson Andrew N. , Gopinath Smita , Nicolau Monica , Khasanova Anna , Finck Rachel , Monack Denise , Nolan Garry P.
Published: January 2016

Multiparametric analysis of immune cell signaling, cytokines, and bacteria identifies connections that balance innate and adaptive immune responses to infection.
Allosteric signaling through an mGlu2 and 5-HT
2A
heteromeric receptor complex and its potential contribution to schizophrenia
Authors: Moreno José L. , Miranda-Azpiazu Patricia , García-Bea Aintzane , Younkin Jason , Cui Meng , Kozlenkov Alexey , Ben-Ezra Ariel , Voloudakis Georgios , Fakira Amanda K. , Baki Lia , Ge Yongchao , Georgakopoulos Anastasios , Morón José A. , Milligan Graeme , López-Giménez Juan F. , Robakis Nikolaos K. , Logothetis Diomedes E. , Meana J. Javier , González-Maeso Javier
Published: January 2016

Stimulation of one partner in a heteromeric GPCR complex in the brain activates the other partner.
Science Signaling
Podcast for 12 January 2016: GPCR heteromers and schizophrenia
Authors: González-Maeso Javier , VanHook Annalisa M.
Published: January 2016

Ligand binding to one member of a heteromeric GPCR complex can activate its binding partner.
Papers of note in
Science Translational Medicine
Authors: Gough Nancy R.
Published: January 2016

This week’s article features insights into how the complement system contributes to sleep apnea.
Papers of note in
Science
Authors: Gough Nancy R.
Published: January 2016

This week’s article features insights into how receptor glycosylation is important for immune-cell guidance.
Killing of Trypanozoon Parasites by the Equine Cathelicidin eCATH1
Authors: Cauchard S. , Van Reet N. , Büscher P. , Goux D. , Grötzinger J. , Leippe M. , Cattoir V. , Laugier C. , Cauchard J.
Published: January 2016

Trypanozoon
parasites infect both humans, causing sleeping sickness, and animals, causing nagana, surra, and dourine. Control of nagana and surra depends to a great extent on chemotherapy. However, drug resistance to several of the front-line drugs is rising. Furthermore, there is no official treatment for dourine. Therefore, there is an urgent need to develop antiparasitic agents with novel modes of action. Host defense peptides have recently gained attention as promising candidates. We have previously reported that one such peptide, the equine antimicrobial peptide eCATH1, is highly active against equine Gram-positive and Gram-negative bacteria, without cytotoxicity against mammalian cells at bacteriolytic concentrations. In the present study, we show that eCATH1 exhibits an
in vitro
50% inhibitory concentration (IC
50
) of 9.5 μM against
Trypanosoma brucei brucei
,
Trypanosoma evansi
, and
Trypanosoma equiperdum
. Its trypanocidal mechanism involves plasma membrane permeabilization and mitochondrial alteration based on the following data: (i) eCATH1 induces the rapid influx of the vital dye SYTOX Green; (ii) it rapidly disrupts mitochondrial membrane potential, as revealed by immunofluorescence microscopy using the fluorescent dye rhodamine 123; (iii) it severely damages the membrane and intracellular structures of the parasites as early as 15 min after exposure at 9.5 μM and 5 min after exposure at higher concentrations (19 μM), as evidenced by scanning and transmission electron microscopy. We also demonstrate that administration of eCATH1 at a dose of 10 mg/kg to
T. equiperdum
-infected mice delays mortality. Taken together, our findings suggest that eCATH1 is an interesting template for the development of novel therapeutic agents in the treatment of trypanosome infections.
Aminophthalocyanine-Mediated Photodynamic Inactivation of Leishmania tropica
Authors: Al-Qahtani Ahmed , Alkahtani Saad , Kolli Bala , Tripathi Pankaj , Dutta Sujoy , Al-Kahtane Abdullah A. , Jiang Xiong-Jie , Ng Dennis K. P. , Chang Kwang Poo
Published: January 2016

Photodynamic inactivation of
Leishmania
spp. requires the cellular uptake of photosensitizers, e.g., endocytosis of silicon(IV)-phthalocyanines (PC) axially substituted with bulky ligands. We report here that when substituted with amino-containing ligands, the PCs (PC1 and PC2) were endocytosed and displayed improved potency against
Leishmania tropica
promastigotes and axenic amastigotes
in vitro
. The uptake of these PCs by both
Leishmania
stages followed saturation kinetics, as expected. Sensitive assays were developed for assessing the photodynamic inactivation of
Leishmania
spp. by rendering them fluorescent in two ways: transfecting promastigotes to express green fluorescent protein (GFP) and loading them with carboxyfluorescein succinimidyl ester (CFSE). PC-sensitized
Leishmania tropica
strains were seen microscopically to lose their motility, structural integrity, and GFP/CFSE fluorescence after exposure to red light (wavelength, ∼650 nm) at a fluence of 1 to 2 J cm
−2
. Quantitative fluorescence assays based on the loss of GFP/CFSE from live
Leishmania tropica
showed that PC1 and PC2 dose dependently sensitized both stages for photoinactivation, consistent with the results of a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) cell viability assay.
Leishmania tropica
strains are >100 times more sensitive than their host cells or macrophages to PC1- and PC2-mediated photoinactivation, judging from the estimated 50% effective concentrations (EC
50
s) of these cells. Axial substitution of the PC with amino groups instead of other ligands appears to increase its leishmanial photolytic activity by up to 40-fold. PC1 and PC2 are thus potentially useful for photodynamic therapy of leishmaniasis and for oxidative photoinactivation of
Leishmania
spp. for use as vaccines or vaccine carriers.
Prospective, Controlled Study of Acyclovir Pharmacokinetics in Obese Patients
Authors: Turner R. Brigg , Cumpston Aaron , Sweet Michael , Briggs Frank , Slain Douglas , Wen Sijin , Craig Michael , Hamadani Mehdi , Petros William
Published: January 2016

The current recommendations for intravenous (i.v.) acyclovir dosing in obese patients suggest using ideal body weight (IBW) rather than total body weight (TBW). To our knowledge, no pharmacokinetic analysis has validated this recommendation. This single-dose pharmacokinetic study was conducted in an inpatient oncology population. Enrollment was conducted by 1:1 matching of obese patients (>190% of IBW) to normal-weight patients (80 to 120% of IBW). All patients received a single dose of i.v. acyclovir, 5 mg/kg, infused over 60 min. Consistent with current recommendations, IBW was used for obese patients and TBW for normal-weight patients. Serial plasma concentrations were obtained and compared. Seven obese and seven normal-weight patients were enrolled, with mean body mass indexes of 45.0 and 22.5 kg/m
2
, respectively. Systemic clearance was substantially higher in the obese than normal-weight patients (mean, 19.4 ± 5.3 versus 14.3 ± 5.4 liters/h;
P
= 0.047). Area under the concentration-time curve was lower in the obese patients (15.2 ± 2.9 versus 24.0 ± 9.4 mg · h/liter;
P
= 0.011), as was maximum concentration (5.8 ± 0.9 versus 8.2 ± 1.3 mg/liter;
P
= 0.031). Utilization of IBW for dose calculation of i.v. acyclovir in obese patients leads to lower systemic exposure than dosing by TBW in normal-weight patients. While not directly evaluated in this study, utilization of an adjusted body weight for dose determination appears to more closely approximate the exposure seen in normal-weight patients. (This study has been registered at ClinicalTrials.gov under registration no. NCT01714180.)
A Complex Network of Interactions between S282 and G283 of Hepatitis C Virus Nonstructural Protein 5B and the Template Strand Affects Susceptibility to Sofosbuvir and Ribavirin
Authors: Kulkarni Anupriya S. , Damha Masad J. , Schinazi Raymond F. , Mo Hongmei , Doehle Brian , Sagan Selena M. , Götte Matthias
Published: January 2016

The hepatitis C virus (HCV) RNA-dependent RNA-polymerase NS5B is essentially required for viral replication and serves as a prominent drug target. Sofosbuvir is a prodrug of a nucleotide analog that interacts selectively with NS5B and has been approved for HCV treatment in combination with ribavirin. Although the emergence of resistance to sofosbuvir is rarely seen in the clinic, the S282T mutation was shown to decrease susceptibility to this drug. S282T was also shown to confer hypersusceptibility to ribavirin, which is of potential clinical benefit. Here we devised a biochemical approach to elucidate the underlying mechanisms. Recent crystallographic data revealed a hydrogen bond between S282 and the 2′-hydroxyl of the bound nucleotide, while the adjacent G283 forms a hydrogen bond with the 2′-hydroxyl of the residue of the template that base pairs with the nucleotide substrate. We show that DNA-like modifications of the template that disrupt hydrogen bonding with G283 cause enzyme pausing with natural nucleotides. However, the specifically introduced DNA residue of the template reestablishes binding and incorporation of sofosbuvir in the context of S282T. Moreover, the DNA-like modifications of the template prevent the incorporation of ribavirin in the context of the wild-type enzyme, whereas the S282T mutant enables the binding and incorporation of ribavirin under the same conditions. Together, these findings provide strong evidence to show that susceptibility to sofosbuvir and ribavirin depends crucially on a network of interdependent hydrogen bonds that involve the adjacent residues S282 and G283 and their interactions with the incoming nucleotide and complementary template residue, respectively.
Colistin-Nonsusceptible Pseudomonas aeruginosa Sequence Type 654 with
bla
NDM-1
Arrives in North America
Authors: Mataseje L. F. , Peirano G. , Church D. L. , Conly J. , Mulvey M. , Pitout J. D.
Published: January 2016

This study describes 3 different
bla
NDM-1
genetic platforms in 3 different species obtained from the same patient who was directly transferred to an institution in Calgary, Alberta, Canada, following a prolonged hospital stay in India. The
bla
NDM-1
in the
Escherichia coli
isolate was located on a 176-kb IncA/C plasmid contained within an IS
CR1
region. The
bla
NDM-1
in the
Providencia rettgeri
isolate was located on a 117-kb IncT plasmid contained within Tn
3000
, while the
bla
NDM-1
in the
Pseudomonas aeruginosa
isolate was located on the chromosome within an IS
CR3
region. This report highlights the plasticity of the genetic regions and environments associated with
bla
NDM-1
. To the best of our knowledge, this is the first report of
P. aeruginosa
with
bla
NDM-1
identified in North America and the first report of
bla
OXA-181
in
P. rettgeri
. The
P. aeruginosa
isolate belonged to the international high-risk sequence type 654 clone and was nonsusceptible to colistin. This case emphasizes the need for the use of appropriate infection prevention and control measures and vigilant screening for carbapenem-resistant Gram-negative bacteria in patients with a history of travel to areas of endemicity, such as the Indian subcontinent.
Colistin Resistance Caused by Inactivation of the MgrB Regulator Is Not Associated with Decreased Virulence of Sequence Type 258 KPC Carbapenemase-Producing Klebsiella pneumoniae
Authors: Arena Fabio , Henrici De Angelis Lucia , Cannatelli Antonio , Di Pilato Vincenzo , Amorese Marina , D'Andrea Marco Maria , Giani Tommaso , Rossolini Gian Maria
Published: January 2016

Using a
Galleria mellonella
animal model, we compared the virulence of two sequence type 258 (ST258) KPC-producing
Klebsiella pneumoniae
strains, which were representative of the two clades of this clonal lineage, with that of isogenic colistin-resistant
mgrB
mutants. With both strains, the
mgrB
mutants did not exhibit modification in virulence. In the
G. mellonella
model, the clade 1 strain (capsular type
cps-1
[
wzi29
, producing KPC-2]) was significantly more virulent than the clade 2 strain (capsular type
cps-2
[
wzi154
, producing KPC-3]).
Highly Drug-Resistant Salmonella enterica Serovar Indiana Clinical Isolates Recovered from Broilers and Poultry Workers with Diarrhea in China
Authors: Gong Jiansen , Wang Chengming , Shi Shourong , Bao Hongduo , Zhu Chunhong , Kelly Patrick , Zhuang Linlin , Lu Guangwu , Dou Xinhong , Wang Ran , Xu Bu , Zou Jianmin
Published: January 2016

Highly drug-resistant
Salmonella enterica
serovar Indiana became the most common serovar in broilers with diarrhea in China over the course of this study (15% in 2010 to 70% in 2014). While most
S
. Indiana isolates (87%, 384/440) were resistant to 13 to 16 of the 16 antibiotics tested, 89% of non-
S
. Indiana isolates (528/595) were resistant to 0 to 6 antibiotics. Class 1 integrons and IncHI2-type plasmids were detected in all
S
. Indiana isolates, but only in 39% and 1% of non-
S
. Indiana isolates.
Analysis of TcdB Proteins within the Hypervirulent Clade 2 Reveals an Impact of RhoA Glucosylation on Clostridium difficile Proinflammatory Activities
Authors: Quesada-Gómez Carlos , López-Ureña Diana , Chumbler Nicole , Kroh Heather K. , Castro-Peña Carolina , Rodríguez César , Orozco-Aguilar Josué , González-Camacho Sara , Rucavado Alexandra , Guzmán-Verri Caterina , Lawley Trevor D. , Lacy D. Borden , Chaves-Olarte Esteban
Published: January 2016

Clostridium difficile
strains within the hypervirulent clade 2 are responsible for nosocomial outbreaks worldwide. The increased pathogenic potential of these strains has been attributed to several factors but is still poorly understood. During a
C. difficile
outbreak, a strain from this clade was found to induce a variant cytopathic effect (CPE), different from the canonical arborizing CPE. This strain (NAP1
V
) belongs to the NAP1 genotype but to a ribotype different from the epidemic NAP1/RT027 strain. NAP1
V
and NAP1 share some properties, including the overproduction of toxins, the binary toxin, and mutations in
tcdC
. NAP1
V
is not resistant to fluoroquinolones, however. A comparative analysis of TcdB proteins from NAP1/RT027 and NAP1
V
strains indicated that both target Rac, Cdc42, Rap, and R-Ras but only the former glucosylates RhoA. Thus, TcdB from hypervirulent clade 2 strains possesses an extended substrate profile, and RhoA is crucial for the type of CPE induced. Sequence comparison and structural modeling revealed that TcdB
NAP1
and TcdB
NAP1V
share the receptor-binding and autoprocessing activities but vary in the glucosyltransferase domain, consistent with the different substrate profile. Whereas the two toxins displayed identical cytotoxic potencies, TcdB
NAP1
induced a stronger proinflammatory response than TcdB
NAP1V
as determined in
ex vivo
experiments and animal models. Since immune activation at the level of intestinal mucosa is a hallmark of
C. difficile
-induced infections, we propose that the panel of substrates targeted by TcdB is a determining factor in the pathogenesis of this pathogen and in the differential virulence potential seen among
C. difficile
strains.
Association of O-Antigen Serotype with the Magnitude of Initial Systemic Cytokine Responses and Persistence in the Urinary Tract
Authors: Horvath Dennis J. , Patel Ashay S. , Mohamed Ahmad , Storm Douglas W. , Singh Chandra , Li Birong , Zhang Jingwen , Koff Stephen A. , Jayanthi Venkata R. , Mason Kevin M. , Justice Sheryl S.
Published: January 2016

Urinary tract infection (UTI) is one of the most common ailments requiring both short-term and prophylactic antibiotic therapies. Progression of infection from the bladder to the kidney is associated with more severe clinical symptoms (e.g., fever and vomiting) as well as with dangerous disease sequelae (e.g., renal scaring and sepsis). Host-pathogen interactions that promote bacterial ascent to the kidney are not completely understood. Prior studies indicate that the magnitude of proinflammatory cytokine elicitation
in vitro
by clinical isolates of uropathogenic
Escherichia coli
(UPEC) inversely correlates with the severity of clinical disease. Therefore, we hypothesize that the magnitude of initial proinflammatory responses during infection defines the course and severity of disease. Clinical UPEC isolates obtained from patients with a nonfebrile UTI elicited high systemic proinflammatory responses early during experimental UTI in a murine model and were attenuated in bladder and kidney persistence. Conversely, UPEC isolates obtained from patients with febrile UTI elicited low systemic proinflammatory responses early during experimental UTI and exhibited prolonged persistence in the bladder and kidney. Soluble factors in the supernatant from saturated cultures as well as the lipopolysaccharide (LPS) serotype correlated with the magnitude of proinflammatory responses
in vitro
. Our data suggest that the structure of the O-antigen sugar moiety of the LPS may determine the strength of cytokine induction by epithelial cells. Moreover, the course and severity of disease appear to be the consequence of the magnitude of initial cytokines produced by the bladder epithelium during infection.

IMPORTANCE
The specific host-pathogen interactions that determine the extent and course of disease are not completely understood. Our studies demonstrate that modest changes in the magnitude of cytokine production observed using
in vitro
models of infection translate into significant ramifications for bacterial persistence and disease severity. While many studies have demonstrated that modifications of the LPS lipid A moiety modulate the extent of Toll-like receptor 4 (TLR4) activation, our studies implicate the O-antigen sugar moiety as another potential rheostat for the modulation of proinflammatory cytokine production.
Kaposi's sarcoma presenting as violaceous macules on the chest of a kidney transplanted patient
Authors: Borges-Costa João , Lopes Leonor , Soares-Almeida Luís , Guerra José
Published: January 2016

Organ transplant recipients have a high incidence of cancer associated with persistent viral infections, such as human herpes virus 8. This virus is associated with Kaposi's sarcoma, and a change in the dose or type of immunosuppression regimen should be the first step in its treatment. A multidisciplinary approach with nephrologists, dermatologists and oncologists is necessary for the management of this disease. We report a clinical case with atypical presentation and discuss the treatment options.
Rare case of Mirizzi syndrome associated with cholecystogastric fistula
Authors: Aldekhayel Mosaed , Almohaimeed Khalid , AlShahrani Mohammad Saad , Almweisheer Shaza
Published: January 2016

A woman in her mid-30s presented with upper right quadrant abdominal pain. On examination, there was mild upper right quadrant tenderness and negative Murphy's sign. Basic laboratory investigations revealed normal results except for elevated alkaline phosphatase. Subsequent imaging revealed chronic calculous cholecystitis and the dilated common bile duct harbouring stones, with pneumobilia. The patient underwent open cholecystectomy with common bile duct exploration. Intraoperatively, the gallbladder was found contracted, and densely adherent to and fistulising with the common bile duct and stomach.
A rare presentation of bilateral spontaneous superficial femoral arteriovenous fistulas
Authors: Hwang Inyong , Bomb Kavita , Askari Raza , Khouzam Rami N
Published: January 2016

Spontaneous arteriovenous fistulas are a rare clinical entity with very few cases reported in the literature. Prompt diagnosis and treatment is crucial and can prevent further complications in such patients. We report a case of a patient who presented with progressive bilateral claudication, discolouration of feet, hypaesthesia and non-healing ulcers. The patient had no history of trauma, aneurysm or surgery. After abnormal non-invasive studies, a peripheral angiogram revealed significant disease and obstruction of bilateral superficial femoral arteries. Spontaneous bilateral femoral arteriovenous fistulas were also found incidentally. After discussing the risks and benefits of multiple treatment options with the patient, percutaneous intervention with orbital atherectomy, balloon angioplasty and covered stent placements were performed. This treatment improved the patient's symptoms significantly.
Nystagmus in a newborn: a manifestation of Joubert syndrome in the neonatal period
Authors: Salva Inês , Albuquerque Carolina , Moreira Ana , Dâmaso Catarina
Published: January 2016

Joubert syndrome is a rare disorder, usually autosomal recessive, with a prevalence of 1:80 000 to 1:100 000. This disease presents most commonly as breathing irregularities, although the two major clinical criteria are hypotonia and developmental delay, sometimes associated with ocular movement abnormalities. The severity of the presentation varies, ranging from mild cases with normal intelligence to severe developmental delays associated with early death. We report a case of a newborn who presented to the emergency department for absent ocular fixation and torsional nystagmus without other neurological abnormalities. Her cranial MR showed cerebellar vermis agenesis and a molar tooth sign. Her laboratory evaluation, and renal and abdominal ultrasound were normal. An electroretinogram showed mixed retinal dystrophy and an AHI1 homozygous missense c.1981T>C mutation was identified (parents are carriers). Throughout infancy, she has shown mild developmental delay and hypotonia, but no respiratory abnormalities. Owing to variable expressivity, a high level of suspicion is required.
Myxoedema coma in the setting of hyperglycaemic hyperosmolar state
Authors: Spyridoulias Alexander , Riaz Muhammad Shakeel
Published: January 2016

Decompensated hypothyroidism is a rare endocrine emergency but a differential that should be considered in patients presenting critically unwell with systemic illness. We report a case of myxoedema coma in a woman presenting with respiratory failure, hypotension, hypothermia and a reduced level of consciousness, all of which are poor prognostic features in decompensated hypothyroidism. The patient was admitted to critical care for mechanical ventilation and cardiovascular support and treated with a combination of insulin, liothyronine and levothyroxine, making a good recovery. We wanted to highlight this case of myxoedema coma occurring in the context of a hyperglycaemic hyperosmolar state (HHS), as the former condition is normally associated with hypoglycaemia, hyponatraemia and hypo-osmolality. Decompensated hypothyroidism should be considered in presentations of HHS as well as with other metabolic derangements, as delays in thyroid hormone replacement are associated with poorer outcomes. It has multisystem effects challenging its recognition and we discuss potential complications and their management.
Acute necrotising encephalopathy in a child with H1N1 influenza infection: a clinicoradiological diagnosis and follow-up
Authors: Yoganathan Sangeetha , Sudhakar Sniya Valsa , James Ebor Jacob , Thomas Maya Mary
Published: January 2016

Acute necrotising encephalopathy of childhood (ANEC) is a fulminant disorder with rapid progressive encephalopathy, seizures and poor outcome. It has been reported in association with various viral infections. We describe the clinicoradiological findings and short-term follow-up in a child with H1N1 influenza-associated ANEC. Laminar, target or tricolour pattern of involvement of the thalami was seen on apparent diffusion coefficient images. Our patient had significant morbidity at discharge despite early diagnosis and management with oseltamivir and immunoglobulin. Repeat imaging after 3 months had shown significant resolution of thalamic swelling, but there was persistence of cytotoxic oedema involving bilateral thalami. She was pulsed with intravenous steroids and maintained on a tapering schedule of oral steroids. This report emphasises the need for a high index of suspicion to establish early diagnosis, promotion of widespread immunisation strategies to prevent influenza outbreak, and more research to establish standard treatment protocols for this under-recognised entity.
To stop or not? Tamoxifen therapy for secondary prevention of breast cancer in a patient with ocular toxicity
Authors: Bommireddy Tejaswi , Carrim Zia Iqbal
Published: January 2016

We report a case of a patient with treated breast cancer whose dilated fundus examination showed crystalline deposits in the central region of the macula. She was taking tamoxifen for secondary prevention. Optical coherence tomography revealed individual refractile deposits associated with intraretinal cysts in both eyes. Tamoxifen-related retinopathy was suspected. A decision to discontinue treatment with tamoxifen was considered but had to be taken in conjunction with the oncologist.
Xanthelasma palpebrarum: a new side effect of nilotinib
Authors: Sayin Irmak , Ayli Meltem , Oğuz Ali Kemal , Cengiz Seval Güldane
Published: January 2016

Chronic myeloid leucaemia (CML) is a chronic myeloproliferative disorder characterised by a reciprocal translocation between the chromosomes 9 and 22 resulting in constitutionally active tyrosine kinase signalling. BCR-ABL tyrosine kinase inhibitors (TKIs) are highly effective molecules in the treatment of CML. Unfortunately, these novel therapeutic agents are accompanied by various side effects, and haematological, cutaneous and metabolic abnormalities are among the most prevalent. Nilotinib, a second-generation TKI, has been shown to cause both—cutaneous lesions and lipid profile abnormalities. We present two CML cases developing xanthelasma palpebrarum while receiving nilotinib. Case 1 also acquired a lipid abnormality following the start of nilotinib therapy, while case 2 meanwhile stayed normolipidemic. In addition to a low cholesterol diet, atorvastatin was prescribed to case 1. Currently, both cases are normolipidemic and continuing their nilotinib therapy. Xanthelasma palpebrarum secondary to nilotinib therapy is new to the literature.
Qualitative study of barriers to cervical cancer screening among Nigerian women
Authors: Isa Modibbo Fatima , Dareng Eileen , Bamisaye Patience , Jedy-Agba Elima , Adewole Ayodele , Oyeneyin Lawal , Olaniyan Olayinka , Adebamowo Clement
Published: January 2016

Objectives

To explore the barriers to cervical cancer screening, focusing on religious and cultural factors, in order to inform group-specific interventions that may improve uptake of cervical cancer screening programmes.

Design

We conducted four focus group discussions among Muslim and Christian women in Nigeria.

Setting

Discussions were conducted in two hospitals, one in the South West and the other in the North Central region of Nigeria.

Participants

27 Christian and 22 Muslim women over the age of 18, with no diagnosis of cancer.

Results

Most participants in the focus group discussions had heard about cervical cancer except Muslim women in the South Western region who had never heard about cervical cancer. Participants believed that wizardry, multiple sexual partners and inserting herbs into the vagina cause cervical cancer. Only one participant knew about the human papillomavirus. Among the Christian women, the majority of respondents had heard about cervical cancer screening and believed that it could be used to prevent cervical cancer. Participants mentioned religious and cultural obligations of modesty, gender of healthcare providers, fear of disclosure of results, fear of nosocomial infections, lack of awareness, discrimination at hospitals, and need for spousal approval as barriers to uptake of screening. These barriers varied by religion across the geographical regions.

Conclusions

Barriers to cervical cancer screening vary by religious affiliations. Interventions to increase cervical cancer awareness and screening uptake in multicultural and multireligious communities need to take into consideration the varying cultural and religious beliefs in order to design and implement effective cervical cancer screening intervention programmes.