bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Acinetobacter baumannii Omp33-36 Porin Is a Virulence Factor That Induces Apoptosis and Modulates Autophagy in Human Cells
Authors: Rumbo Carlos , Tomás María , Fernández Moreira Esteban , Soares Nelson Cruz , Carvajal Micaela , Santillana Elena , Beceiro Alejandro , Romero Antonio , Bou Germán 
Published: August 2014

ABSTRACT

Acinetobacter baumannii
is an extracellular opportunistic human pathogen that is becoming increasingly problematic in hospitals. In the present study, we demonstrate that the
A. baumannii
Omp 33- to 36-kDa protein (Omp33-36) is a porin that acts as a channel for the passage of water. The protein is found on the cell surface and is released along with other porins in the outer membrane vesicles (OMVs). In immune and connective cell tissue, this protein induced apoptosis by activation of caspases and modulation of autophagy, with the consequent accumulation of p62/SQSTM1 (sequestosome 1) and LC3B-II (confirmed by use of autophagy inhibitors). Blockage of autophagy enables the bacterium to persist intracellularly (inside autophagosomes), with the subsequent development of cytotoxicity. Finally, we used macrophages and a mouse model of systemic infection to confirm that Omp33-36 is a virulence factor in
A. baumannii
. Overall, the study findings show that Omp33-36 plays an important role in the pathogenesis of
A. baumannii
infections.
Monoclonal Antibodies against Vibrio vulnificus RtxA1 Elicit Protective Immunity through Distinct Mechanisms
Authors: Lee Tae Hee , Cha Sun-Shin , Lee Chang-Seop , Rhee Joon Haeng , Chung Kyung Min 
Published: August 2014

ABSTRACT

Vibrio vulnificus
causes rapidly progressing septicemia with an extremely high mortality rate (≥50%), even with aggressive antibiotic treatment. The bacteria secrete multifunctional autoprocessing repeats-in-toxin (MARTX) toxins, which are involved in the pathogenesis of Gram-negative
Vibrio
species. Recently, we reported that immunization with the C-terminal region of
V. vulnificus
RtxA1/MARTX
Vv
, RtxA1-C, elicits a protective immune response against
V. vulnificus
through a poorly defined mechanism. In this study, we generated a panel of new monoclonal antibodies (MAbs) against
V. vulnificus
RtxA1-C and investigated their protective efficacies and mechanisms in a mouse model of infection. Prophylactic administration of seven MAbs strongly protected mice against lethal
V. vulnificus
infection (more than 90% survival). Moreover, three of these MAbs (21RA, 24RA, and 47RA) demonstrated marked efficacy as postexposure therapy. Notably, 21RA was therapeutically effective against lethal
V. vulnificus
infection by a variety of routes. Using Fab fragments and a neutropenic mouse model, we showed that 21RA and 24RA mediate protection from
V. vulnificus
infection through an Fc-independent and/or neutrophil-independent pathway. In contrast, 47RA-mediated protection was dependent on its Fc region and was reduced to 50% in neutropenic mice compared with 21RA-mediated and 24RA-mediated protection. Bacteriological study indicated that 21RA appears to enhance the clearance of
V. vulnificus
from the blood. Overall, these studies suggest that humoral immunity controls
V. vulnificus
infection through at least two different mechanisms. Furthermore, our panel of MAbs could provide attractive candidates for the further development of immunoprophylaxis/therapeutics and other therapies against
V. vulnificus
that target the MARTX toxin.
Synergistic Interactions of Pseudomonas aeruginosa and Staphylococcus aureus in an
In Vitro
Wound Model
Authors: DeLeon Stephanie , Clinton Allie , Fowler Haley , Everett Jake , Horswill Alexander R. , Rumbaugh Kendra P. 
Published: August 2014

ABSTRACT

In individuals with polymicrobial infections, microbes often display synergistic interactions that can enhance their colonization, virulence, or persistence. One of the most prevalent types of polymicrobial infection occurs in chronic wounds, where
Pseudomonas aeruginosa
and
Staphylococcus aureus
are the two most common causes. Although they are the most commonly associated microbial species in wound infections, very little is known about their interspecies relationship. Evidence suggests that
P. aeruginosa
–
S. aureus
coinfections are more virulent than monoculture infection with either species; however, difficulties in growing these two pathogens together
in vitro
have hampered attempts to uncover the mechanisms involved. Here we describe a simple and clinically relevant
in vitro
wound model that supported concomitant growth of
P. aeruginosa
and
S. aureus
. We observed that the ability of
P. aeruginosa
and
S. aureus
to survive antibiotic treatment increased when they were grown together in planktonic cocultures and that antibiotic tolerance was further enhanced when they were grown together in the wound model. We attributed this enhanced tolerance to both the “host-derived” and “bacterium-derived” matrix components. Taken together, our data indicate that
P. aeruginosa
and
S. aureus
may benefit each other by coinfecting wounds and that the host-derived matrix may serve as important a role as the bacterium-derived matrix in protecting bacteria from some antibiotics.
Mycoplasma pneumoniae, an Underutilized Model for Bacterial Cell Biology
Authors: Balish Mitchell F. 
Published: August 2014

ABSTRACT

In recent decades, bacterial cell biology has seen great advances, and numerous model systems have been developed to study a wide variety of cellular processes, including cell division, motility, assembly of macromolecular structures, and biogenesis of cell polarity. Considerable attention has been given to these model organisms, which include
Escherichia coli
,
Bacillus subtilis
,
Caulobacter crescentus
, and
Myxococcus xanthus
. Studies of these processes in the pathogenic bacterium
Mycoplasma pneumoniae
and its close relatives have also been carried out on a smaller scale, but this work is often overlooked, in part due to this organism's reputation as minimalistic and simple. In this minireview, I discuss recent work on the role of the
M. pneumoniae
attachment organelle (AO), a structure required for adherence to host cells, in these processes. The AO is constructed from proteins that generally lack homology to those found in other organisms, and this construction occurs in coordination with cell cycle events. The proteins of the
M. pneumoniae
AO share compositional features with proteins with related roles in model organisms. Once constructed, the AO becomes activated for its role in a form of gliding motility whose underlying mechanism appears to be distinct from that of other gliding bacteria, including
Mycoplasma mobile
. Together with the FtsZ cytoskeletal protein, motility participates in the cell division process. My intention is to bring this deceptively complex organism into alignment with the better-known model systems.
Evidence against Translational Repression by the Carboxyltransferase Component of Escherichia coli Acetyl Coenzyme A Carboxylase
Authors: Smith Alexander C. , Cronan John E. 
Published: August 2014

ABSTRACT

In
Escherichia coli
, synthesis of the malonyl coenzyme A (malonyl-CoA) required for membrane lipid synthesis is catalyzed by acetyl-CoA carboxylase, a large complex composed of four subunits. The subunit proteins are needed in a defined stoichiometry, and it remains unclear how such production is achieved since the proteins are encoded at three different loci. Meades and coworkers (G. Meades, Jr., B. K. Benson, A. Grove, and G. L. Waldrop, Nucleic Acids Res. 38:1217–1227, 2010, doi:
http://dx.doi.org/10.1093/nar/gkp1079
) reported that coordinated production of the AccA and AccD subunits is due to a translational repression mechanism exerted by the proteins themselves. The AccA and AccD subunits form the carboxyltransferase (CT) heterotetramer that catalyzes the second partial reaction of acetyl-CoA carboxylase. Meades et al. reported that CT tetramers bind the central portions of the
accA
and
accD
mRNAs and block their translation
in vitro
. However, long mRNA molecules (500 to 600 bases) were required for CT binding, but such long mRNA molecules devoid of ribosomes seemed unlikely to exist
in vivo
. This, plus problematical aspects of the data reported by Meades and coworkers, led us to perform
in vivo
experiments to test CT tetramer-mediated translational repression of the
accA
and
accD
mRNAs. We report that increased levels of CT tetramer have no detectable effect on translation of the CT subunit mRNAs.
Phenotypic Interactions among Mutations in a Thermus thermophilus 16S rRNA Gene Detected with Genetic Selections and Experimental Evolution
Authors: Gregory Steven T. , Connetti Jacqueline L. , Carr Jennifer F. , Jogl Gerwald , Dahlberg Albert E. 
Published: August 2014

ABSTRACT

During protein synthesis, the ribosome undergoes conformational transitions between functional states, requiring communication between distant structural elements of the ribosome. Despite advances in ribosome structural biology, identifying the protein and rRNA residues governing these transitions remains a significant challenge. Such residues can potentially be identified genetically, given the predicted deleterious effects of mutations stabilizing the ribosome in discrete conformations and the expected ameliorating effects of second-site compensatory mutations. In this study, we employed genetic selections and experimental evolution to identify interacting mutations in the ribosome of the thermophilic bacterium
Thermus thermophilus
. By direct genetic selections, we identified mutations in 16S rRNA conferring a streptomycin dependence phenotype and from these derived second-site suppressor mutations relieving dependence. Using experimental evolution of streptomycin-independent pseudorevertants, we identified additional compensating mutations. Similar mutations could be evolved from slow-growing streptomycin-resistant mutants. While some mutations arose close to the site of the original mutation in the three-dimensional structure of the 30S ribosomal subunit and probably act directly by compensating for local structural distortions, the locations of others are consistent with long-range communication between specific structural elements within the ribosome.
Fifty-five per cent return to competitive sport following anterior cruciate ligament reconstruction surgery: an updated systematic review and meta-analysis including aspects of physical functioning and contextual factors
Authors: Ardern Clare L , Taylor Nicholas F , Feller Julian A , Webster Kate E 
Published: August 2014

BackgroundThe aim of this study was to update our original systematic review of return to sport rates following anterior cruciate ligament (ACL) reconstruction surgery.MethodElectronic databases were searched from April 2010 to November 2013 for articles reporting the number of patients returning to sport following ACL reconstruction surgery. Return to sport rates, physical functioning and contextual data were extracted and combined using random-effects meta-analyses. Data from the original review (articles published up to April 2010) were combined with data from the updated search.ResultsSixty-nine articles, reporting on 7556 participants, were reviewed. On average, 81% of people returned to any sport, 65% returned to their preinjury level of sport and 55% returned to competitive level sport after surgery. Symmetrical hopping performance (d=0.3) and the contextual factors of younger age (d=−0.3), male gender (OR=1.4), playing elite sport (OR=2.5) and having a positive psychological response (d=0.3) favoured returning to the preinjury level sport. Receiving a hamstring tendon autograft favoured returning to competitive level sport (OR=2.4), whereas receiving a patellar tendon autograft favoured returning to the preinjury level sport (OR=1.2).ConclusionsReturning to sport varied according to different physical functioning and contextual factors, which could warrant additional emphasis in postoperative rehabilitation programmes to maximise participation.
Dilated eye examination screening guideline compliance among patients with diabetes without a diabetic retinopathy diagnosis: the role of geographic access
Authors: Lee David J , Kumar Naresh , Feuer William J , Chou Chiu-Fang , Rosa Potyra R , Schiffman Joyce C , Morante Alexis , Aldahan Adam , Staropoli Patrick , Fernandez Cristina A , Tannenbaum Stacey L , Lam Byron L 
Published: August 2014

ObjectiveTo estimate the prevalence of, and factors associated with, dilated eye examination guideline compliance among patients with diabetes mellitus (DM), but without diabetic retinopathy.Research design and methodsUtilizing the computerized billing records database, we identified patients with International Classification of Diseases (ICD)-9 diagnoses of DM, but without any ocular diagnoses. The available medical records of patients in 2007–2008 were reviewed for demographic and ocular information, including visits through 2010 (n=200). Patients were considered guideline compliant if they returned at least every 15 months for screening. Participant street addresses were assigned latitude and longitude coordinates to assess their neighborhood socioeconomic status (using the 2000 US census data), distance to the screening facility, and public transportation access. Patients not compliant, based on the medical record review, were contacted by phone or mail and asked to complete a follow-up survey to determine if screening took place at other locations.ResultsThe overall screening compliance rate was 31%. Patient sociodemographic characteristics, insurance status, and neighborhood socioeconomic measures were not significantly associated with compliance. However, in separate multivariable logistic regression models, those living eight or more miles from the screening facility were significantly less likely to be compliant relative to those living within eight miles (OR=0.36 (95% CI 0.14 to 0.86)), while public transit access quality was positively associated with screening compliance (1.34 (1.07 to 1.68)).ConclusionsLess than one-third of patients returned for diabetic retinopathy screening at least every 15 months, with transportation challenges associated with noncompliance. Our results suggest that reducing transportation barriers or utilizing community-based screening strategies may improve compliance.
Unusually low prevalence ofMycoplasma genitaliumin urine samples from infertile men and healthy controls: a prevalence study
Authors: Plecko Vanda , Zele-Starcevic Lidija , Tripkovic Vesna , Skerlev Mihael , Ljubojevic Suzana , Plesko Sanja , Marekovic Ivana , Jensen Jorgen Skov 
Published: August 2014

ObjectiveTo detectMycoplasma genitaliumin urine samples of infertile men and men without any signs of infection in order to investigate whetherM. genitaliumand other genital mycoplasmas (Mycoplasma hominisandUreaplasmaspp) are found more often in urine samples of infertile men than in asymptomatic controls and to determine resistance to macrolides.MethodsThe study included first void urine samples taken from 145 infertile men and 49 men with no symptoms of urethritis.M. genitalium, Chlamydia trachomatisandNeisseria gonorrhoeaewere detected by commercial PCR.Trichomonas vaginaliswas detected by microscopy and culture.M. hominisandUreaplasmaspp were detected by culture.M. genitaliumwas detected by in-house conventional and real-time PCR.ResultsTwoM. genitaliumpositive samples were found among samples obtained from infertile men. All asymptomatic men wereM. genitaliumnegative. Macrolide resistance was not found in either of the two positive samples.ConclusionsIn comparison with reported data, an unusually low prevalence ofM. genitaliumwas found in infertile men. The reasons for this unexpected result are not known; possibly, local demographic and social characteristics of the population influenced the result. Further studies to investigateM. genitaliumin infertile and other groups of patients are needed.
Electronic cigarette use among adult population: a cross-sectional study in Barcelona, Spain (2013–2014)
Authors: Martínez-Sánchez Jose M , Ballbè Montse , Fu Marcela , Martín-Sánchez Juan Carlos , Saltó Esteve , Gottlieb Mark , Daynard Richard , Connolly Gregory N , Fernández Esteve 
Published: August 2014

ObjectiveThis study seeks to analyse the prevalence and correlates of electronic cigarette (e-cigarette) use, purchase location and satisfaction with its use in a sample of the general population of the city of Barcelona, Spain.Design, setting and participantsWe used participants from a longitudinal study of a representative sample of the adult (≥16 years old) population of Barcelona (336 men and 400 women). The field work was conducted between May 2013 and February 2014. We computed the prevalence, adjusted odds ratios (ORs) and their corresponding 95% confidence interval (CI).ResultsThe prevalence of ever e-cigarette use was 6.5% (95% CI 4.7% to 8.3%): 1.6% current use, 2.2% past use and 2.7% only e-cigarette experimentation. 75% (95% CI 62.8% to 87.3%) of ever e-cigarette users were current cigarette smokers at the moment of the interview. E-cigarette use was more likely among current smokers (OR=54.57; 95% CI 7.33 to 406.38) and highly dependent cigarette smokers (OR=3.96; 95% CI 1.60 to 9.82). 62.5% of the ever users charged their e-cigarettes with nicotine with 70% of them obtaining the liquids with nicotine in a specialised shop. 39.6% of ever e-cigarette users were not satisfied with their use, a similar percentage of not satisfied expressing the smokers (38.9%) and there were no statistically significant differences in the satisfaction between the users of e-cigarettes with and without nicotine.ConclusionsE-cigarette use is strongly associated with current smoking (dual use) and most users continue to be addicted to nicotine. Six out of 10 e-cigarette users preferred devices that deliver nicotine. The satisfaction with e-cigarette use is very low.
Improving quality in a national intestinal failure unit: greater efficiency, improved access and reduced mortality
Authors: Donaldson Emma , Taylor Michael , Abraham Arun , Carlson Gordon , Fletcher Olivia , Varden Jacqui , Teubner Antje , Lal Simon 
Published: August 2014

ProblemIn 2010, there was a significant waiting list for admission to the intestinal failure unit (IFU) at the Salford Royal National Health Service (NHS) Foundation Trust. There had been a steady increase in the number of new patients referred to the IFU (89 patients 2005; 152 patients 2012) and the number of established patients requiring home parenteral nutrition (HPN) (135 patients 2005; 206 patients 2012) over the last decade. The impact of the resulting long waiting list for these complex patients was that patient deaths occurred in those awaiting admission.DesignContinuous improvement methodology using the model for improvement and sequential plan–do–study–act cycles.SettingSalford Royal NHS Foundation Trust IFU; a large NHS teaching hospital in Northwest England.Key measures for improvementThe primary outcome measures were inpatient length of stay and time spent on waiting list prior to admission.Strategies for changeA continuous improvement programme, supported by a project manager.ResultsThere has been a 21% reduction in average length of stay on the IFU from 55.7 to 44.0 days and a reduction of 72% in the average length of time new patients spent on the waiting list for admission from 65.7 to 18.5 days. These changes were associated with concomitant reduction in 30-day readmission rate from 12.1% to 4.5% and early suggestions of reduced inpatient and waiting list mortality.ConclusionsIt is possible to improve the efficiency of a large national service for complex patients using quality improvement methodology, resulting in improved access and reduced waiting list mortality.
A Survey on DHT-Based Routing for Large-Scale Mobile Ad Hoc Networks
Authors: Abid Shahbaz Akhtar , Othman Mazliza , Shah Nadir 
Published: August 2014

Mobile ad hoc networks (MANETs) are infrastructureless and distributed communication systems that require sophisticated approaches to routing to cope with node mobility and heterogeneous application requirements. In the past few years, distributed hash table (DHT) has come forth as a useful additional technique to the design and specification of spontaneous and self-organized networks. Researchers have exploited its advantages by implementing it at the network layer and developing scalable routing protocols for MANETs. The implementation of DHT-based routing in a MANET requires different algorithms and specifications compared to routing in the Internet because a MANET has its unique characteristics, such as node mobility, spontaneous networking, decentralized architecture, limited transmission range, dynamic topology, and frequent network partitioning/merging.
In this article, we present a comprehensive survey of research related to DHT-based routing that aims at enhancing the scalability of MANETs. We present a vivid taxonomy of DHT-based routing protocols and the guidelines to design such protocols for MANETs. We compare the features, strengths, and weaknesses of existing DHT-based routing protocols and highlight key research challenges that are vital to address. The outcome of the analysis serves as a guide for anyone willing to delve into research on DHT-based routing in MANETs.
The Cancer Prevention and Control Research Network: An Interactive Systems Approach to Advancing Cancer Control Implementation Research and Practice
Authors: Fernández María E. , Melvin Cathy L. , Leeman Jennifer , Ribisl Kurt M. , Allen Jennifer D. , Kegler Michelle C. , Bastani Roshan , Ory Marcia G. , Risendal Betsy C. , Hannon Peggy A. , Kreuter Matthew W. , Hebert James R. 
Published: August 2014

Abstract
Background: Although cancer research has advanced at a rapid pace, a gap remains between what is known about how to improve cancer prevention and control (CPC) and what is implemented as best practices within health care systems and communities. The Cancer Prevention and Control Research Network (CPCRN), with more than 10 years of dissemination and implementation research experience, aims to accelerate the uptake and use of evidence-based CPC interventions.
Methods: The collective work of the CPCRN has facilitated the analysis and categorization of research and implementation efforts according to the Interactive Systems Framework for Dissemination and Implementation (ISF), providing a useful heuristic for bridging the gap between prevention research and practice. The ISF authors have called for examples of its application as input to help refine the model.
Results: We provide examples of how the collaborative activities supported by the CPCRN, using community-engaged processes, accelerated the synthesis and translation of evidence, built both general and innovation-specific capacity, and worked with delivery systems to advance cancer control research and practice.
Conclusions: The work of the CPCRN has provided real-world examples of the application of the ISF and demonstrated that synthesizing and translating evidence can increase the potential that evidence-based CPC programs will be used and that capacity building for both the support system and the delivery system is crucial for the successful implementation and maintenance of evidence-based cancer control.
Impact: Adoption and implementation of CPC can be enhanced by better understanding ISF systems and intervening to improve them. Cancer Epidemiol Biomarkers Prev; 23(11); 2512–21. ©2014 AACR.