bluuebunny/crossref_metadata_2025_split huggingface dataset:
Mechanisms of in vivo muscle fatigue in humans: investigating age‐related fatigue resistance with a computational model
Authors: Callahan Damien M. , Umberger Brian R. , Kent Jane A. 
Published: January 2016

Key points
Muscle fatigue can be defined as the transient decrease in maximal force that occurs in response to muscle use. Fatigue develops because of a complex set of changes within the neuromuscular system that are difficult to evaluate simultaneously in humans.
The skeletal muscle of older adults fatigues less than that of young adults during static contractions. The potential sources of this difference are multiple and intertwined.
To evaluate the individual mechanisms of fatigue, we developed an integrative computational model based on neural, biochemical, morphological and physiological properties of human skeletal muscle.
Our results indicate first that the model provides accurate predictions of fatigue and second that the age‐related resistance to fatigue is due largely to a lower reliance on glycolytic metabolism during contraction.
This model should prove useful for generating hypotheses for future experimental studies into the mechanisms of muscle fatigue.
AbstractDuring repeated or sustained muscle activation, force‐generating capacity becomes limited in a process referred to as fatigue. Multiple factors, including motor unit activation patterns, muscle fibre contractile properties and bioenergetic function, can impact force‐generating capacity and thus the potential to resist fatigue. Given that neuromuscular fatigue depends on interrelated factors, quantifying their independent effects on force‐generating capacity is not possible in vivo. Computational models can provide insight into complex systems in which multiple inputs determine discrete outputs. However, few computational models to date have investigated neuromuscular fatigue by incorporating the multiple levels of neuromuscular function known to impact human in vivo function. To address this limitation, we present a computational model that predicts neural activation, biomechanical forces, intracellular metabolic perturbations and, ultimately, fatigue during repeated isometric contractions. This model was compared with metabolic and contractile responses to repeated activation using values reported in the literature. Once validated in this way, the model was modified to reflect age‐related changes in neuromuscular function. Comparisons between initial and age‐modified simulations indicated that the age‐modified model predicted less fatigue during repeated isometric contractions, consistent with reports in the literature. Together, our simulations suggest that reduced glycolytic flux is the greatest contributor to the phenomenon of age‐related fatigue resistance. In contrast, oxidative resynthesis of phosphocreatine between intermittent contractions and inherent buffering capacity had minimal impact on predicted fatigue during isometric contractions. The insights gained from these simulations cannot be achieved through traditional in vivo or in vitro experimentation alone.
Repair versus shaving of partial-thickness articular-sided tears of the upper subscapularis tendon. A prospective randomized controlled trial
Authors: Randelli Pietro , Arrigoni Paolo , Aliprandi Alberto , Sdao Silvana , Ragone Vincenza , D’Ambrosi Riccardo , Randelli Filippo , Cabitza Paolo , Banfi Giuseppe 
Published: January 2016

Purpose:the purpose of this study was to evaluate whether treating partial-thickness articular-sided tears of the upper subscapularis (SSC) tendon with a dedicated suture anchor would result in an internal rotation strength improvement compared with simple shaving of the SSC tendon and footprint.
Methods: twenty-six patients with a limited SSC tendon tear (equal or inferior to the most superior centimeter) in association with a posterosuperior cuff lesion were prospectively randomized to two treatments: repair with a dedicated suture anchor versus shaving of the tendon and footprint. The patients also underwent long head of the biceps (LHB) treatment and posterosuperior cuff tear repair. In each patient the following parameters were measured both preoperatively and at a minimum follow-up of 2.5 years: strength in internal rotation in the bear-hug testing position (using a digital tensiometer), DASH score and Constant scores. MRI assessment of tendon healing was performed at the final follow-up.
Results: twenty of the 26 patients (76%) were reviewed after a mean follow-up time of 42 months: 11 patients had undergone SSC tendon repair and nine simple shaving. At final follow-up no significant differences were found between the repaired and shaving group in strength in internal rotation (9.5 ± 3.8 kg versus 10.3±5.4 kg; p=0.7). the DASH score and Constant score also failed to show significant differences between the two groups. Furthermore, no significant difference in SSC tendon healing rate was observed on MRI evaluation.
Conclusions: partial-thickness articular-sided tear of the upper SSC tendon in association with a posterosuperior rotator cuff repair and LHB treatment, when limited to the superior centimeter of the SSC tendon, shows a comparable performance in terms of strength in internal rotation either after simple shaving or a tendon-to-bone repair.
Level of evidence: Level II, prospective comparative study.
The management of chronic osteoarticular pain in the outpatient setting: results of an ASON audit
Authors: Mammucari Massimo , Gigliotti Sergio , Pucino Angelo , Capezza Maria , Santé Giuseppe ,   On Behalf of the ASON Study Group
Published: January 2016

The management of patients with chronic osteoarticular pain requires a comprehensive clinical evaluation and a multidisciplinary approach. Thirty specialists (orthopedic specialists, rheumatologists, physiatrists), members of the National Association of Osteoarticular Specialists (ASON), attended a specific training course in the use of a standardized medical record designed for the management of osteoarticular pain in outpatients. An audit on 888 medical records was later conducted and it showed that use of this instrument led to an improvement in the diagnostic-therapeutic
approach.A complete and accurate medical record compilation process may also promote collaborative interaction among the healthcare practitioners involved and this can result in greater efficiency and continuity of care. ASON recommends expediting the use of electronic tools to facilitate information-sharing among pain care specialists. This study shows that the use of electronic tools facilitates the exchange of information between healthcare providers. ASON supports the adoption of similar instruments in order to improve the management of chronic pain.
Level of evidence: Level III, cross-sectional survey.
Genome Sequence of
Janthinobacterium
sp. CG23_2, a Violacein-Producing Isolate from an Antarctic Supraglacial Stream
Authors: Smith Heidi J. , Foreman Christine M. , Akiyama Tatsuya , Franklin Michael J. , Devitt Nicolas P. , Ramaraj Thiruvarangan 
Published: January 2016

ABSTRACT

Here, we present the draft genome sequence for the violacein-producing
Janthinobacterium
sp. CG23_2 isolated from an Antarctic supraglacial stream. The genome is ~7.85 Mb, with a G+C content of 63.5%. The genome includes 7,247 candidate protein coding genes, which may provide insight into UV tolerance mechanisms.
Complete Genome Sequence of Fish Pathogen Aeromonas hydrophila JBN2301
Authors: Yang Wuming , Li Ningqiu , Li Ming , Zhang Defeng , An Guannan 
Published: January 2016

ABSTRACT

Aeromonas hydrophila
is one of the most important fish pathogens in China. Here, we report complete genome sequence of a virulent strain,
A. hydrophila
JBN2301, which was isolated from diseased crucian carp.
Complete Genome Sequence of the Proteorhodopsin-Containing Marine Bacterium
Sediminicola
sp. YIK13
Authors: Kwon Yong Min , Kim Sang-Jin 
Published: January 2016

ABSTRACT

Sediminicola
sp. YIK13 is a marine flavobacterium, isolated from tidal flat sediment. Here, we present the first complete genome sequence of this genus, which consists of 3,569,807 bp with 39.4% GC content. This strain contains proteorhodopsin, as well as retinal biosynthesis genes, allowing it to utilize sunlight as an energy source.
Genome Sequences of Five Arboviruses in Field-Captured Mosquitoes in a Unique Rural Environment of South Korea
Authors: Hang Jun , Klein Terry A. , Kim Heung-Chul , Yang Yu , Jima Dereje D. , Richardson Jason H. , Jarman Richard G. 
Published: January 2016

ABSTRACT

Here, we present the genome sequences of one mesonivirus and four novel arboviruses observed in
Culex bitaeniorhynchus
and
Culex pipiens
, captured in and near the demilitarized zone, Republic of Korea. Results suggest the ubiquitous presence of mesoniviruses and the discovery of a potentially new species of arboviruses in field-captured mosquitoes.
Complete Genome Sequence of KPC-Producing Klebsiella pneumoniae Strain CAV1193
Authors: Sheppard Anna E. , Stoesser Nicole , Sebra Robert , Kasarskis Andrew , Deikus Gintaras , Anson Luke , Walker A. Sarah , Peto Tim E. , Crook Derrick W. , Mathers Amy J. 
Published: January 2016

ABSTRACT

Carbapenem resistance in
Klebsiella pneumoniae
, frequently conferred by the
bla
KPC
gene, is a major public health threat. We sequenced a
bla
KPC
-containing strain of
K. pneumoniae
belonging to the emergent lineage ST941, in order to better understand the evolution of
bla
KPC
within this species.
Genome Sequence of Highly Virulent Pseudomonas aeruginosa Strain VA-134, Isolated from a Burn Patient
Authors: Miller Christine L. , Chen Tsute , Chen Ping , Leung Kai P. 
Published: January 2016

ABSTRACT

Infection with
Pseudomonas aeruginosa
leads to impairment of healing and many deaths in severe burn patients. The phenotypic diversity of
P. aeruginosa
strains makes it difficult to define a therapeutic strategy. Here we report the genome sequence of a highly virulent strain of
P. aeruginosa
, VA-134, isolated from a burn patient.
Draft Genome Sequence of Bacillus amyloliquefaciens Strain RHNK22, Isolated from Rhizosphere with Biosurfactant (Surfactin, Iturin, and Fengycin) and Antifungal Activity
Authors: Narendra Kumar Papathoti , Swapna T. H. , Sathi Reddy Koppula , Archana K. , Nageshwar Lingampalli , Nalini S. , Khan Mohamed Yahya , Hameeda Bee 
Published: January 2016

ABSTRACT

Bacillus amyloliquefaciens
strain RHNK22 isolated from groundnut rhizosphere showed direct and indirect plant growth-promoting traits along with biosurfactant activity and reduction in surface tension of water. Biosurfactants were identified as lipopeptides (surfactin, iturin, and fengycin) by molecular and biochemical analysis in our studies.
Improved Diagnosis of Prosthetic Joint Infection by Culturing Periprosthetic Tissue Specimens in Blood Culture Bottles
Authors: Peel Trisha N. , Dylla Brenda L. , Hughes John G. , Lynch David T. , Greenwood-Quaintance Kerryl E. , Cheng Allen C. , Mandrekar Jayawant N. , Patel Robin 
Published: January 2016

ABSTRACT

Despite known low sensitivity, culture of periprosthetic tissue specimens on agars and in broths is routine. Culture of periprosthetic tissue samples in blood culture bottles (BCBs) is potentially more convenient, but it has been evaluated in a limited way and has not been widely adopted. The aim of this study was to compare the sensitivity and specificity of inoculation of periprosthetic tissue specimens into blood culture bottles with standard agar and thioglycolate broth culture, applying Bayesian latent class modeling (LCM) in addition to applying the Infectious Diseases Society of America (IDSA) criteria for prosthetic joint infection. This prospective cohort study was conducted over a 9-month period (August 2013 to April 2014) at the Mayo Clinic, Rochester, MN, and included all consecutive patients undergoing revision arthroplasty. Overall, 369 subjects were studied; 117 (32%) met IDSA criteria for prosthetic joint infection, and 82% had late chronic infection. Applying LCM, inoculation of tissues into BCBs was associated with a 47% improvement in sensitivity compared to the sensitivity of conventional agar and broth cultures (92.1 versus 62.6%, respectively); this magnitude of change was similar when IDSA criteria were applied (60.7 versus 44.4%, respectively;
P
= 0.003). The time to microorganism detection was shorter with BCBs than with standard media (
P
< 0.0001), with aerobic and anaerobic BCBs yielding positive results within a median of 21 and 23 h, respectively. Results of our study demonstrate that the semiautomated method of periprosthetic tissue culture in blood culture bottles is more sensitive than and as specific as agar and thioglycolate broth cultures and yields results faster.

IMPORTANCE
Prosthetic joint infections are a devastating complication of arthroplasty surgery. Despite this, current microbiological techniques to detect and diagnose infections are imperfect. This study examined a new approach to diagnosing infections, through the inoculation of tissue samples from around the prosthetic joint into blood culture bottles. This study demonstrated that, compared to current laboratory practices, this new technique increased the detection of infection. These findings are important for patient care to allow timely and accurate diagnosis of infection.
An Unexpected Route to an Essential Cofactor: Escherichia coli Relies on Threonine for Thiamine Biosynthesis
Authors: Bazurto Jannell V. , Farley Kristen R. , Downs Diana M. 
Published: January 2016

ABSTRACT

Metabolism consists of biochemical reactions that are combined to generate a robust metabolic network that can respond to perturbations and also adapt to changing environmental conditions.
Escherichia coli
and
Salmonella enterica
are closely related enterobacteria that share metabolic components, pathway structures, and regulatory strategies. The synthesis of thiamine in
S. enterica
has been used to define a node of the metabolic network by analyzing alternative inputs to thiamine synthesis from diverse metabolic pathways. To assess the conservation of metabolic networks in organisms with highly conserved components, metabolic contributions to thiamine synthesis in
E. coli
were investigated. Unexpectedly, we found that, unlike
S. enterica
,
E. coli
does not use the phosphoribosylpyrophosphate (PRPP) amidotransferase (PurF) as the primary enzyme for synthesis of phosphoribosylamine (PRA)
.
In fact, our data showed that up to 50% of the PRA used by
E. coli
to make thiamine requires the activities of threonine dehydratase (IlvA) and anthranilate synthase component II (TrpD). Significantly, the IlvA- and TrpD-dependent pathway to PRA functions in
S. enterica
only in the absence of a functional
r
eactive
i
ntermediate
d
eaminase (RidA) enzyme, bringing into focus how these closely related bacteria have distinct metabolic networks.

IMPORTANCE
In most bacteria, including
Salmonella
strains and
Escherichia coli
, synthesis of the pyrimidine moiety of the essential coenzyme, thiamine pyrophosphate (TPP), shares enzymes with the purine biosynthetic pathway. Phosphoribosylpyrophosphate amidotransferase, encoded by the
purF
gene, generates phosphoribosylamine (PRA) and is considered the first enzyme in the biosynthesis of purines and the pyrimidine moiety of TPP. We show here that, unlike
Salmonella
,
E. coli
synthesizes significant thiamine from PRA derived from threonine using enzymes from the isoleucine and tryptophan biosynthetic pathways. These data show that two closely related organisms can have distinct metabolic network structures despite having similar enzyme components, thus emphasizing caveats associated with predicting metabolic potential from genome content.
Coagulase and Efb of Staphylococcus aureus Have a Common Fibrinogen Binding Motif
Authors: Ko Ya-Ping , Kang Mingsong , Ganesh Vannakambadi K. , Ravirajan Dharmanand , Li Bin , Höök Magnus 
Published: January 2016

ABSTRACT

Coagulase (Coa) and Efb, secreted
Staphylococcus aureus
proteins, are important virulence factors in staphylococcal infections. Coa interacts with fibrinogen (Fg) and induces the formation of fibrin(ogen) clots through activation of prothrombin. Efb attracts Fg to the bacterial surface and forms a shield to protect the bacteria from phagocytic clearance. This communication describes the use of an array of synthetic peptides to identify variants of a linear Fg binding motif present in Coa and Efb which are responsible for the Fg binding activities of these proteins. This motif represents the first Fg binding motif identified for any microbial protein. We initially located the Fg binding sites to Coa’s C-terminal disordered segment containing tandem repeats by using recombinant fragments of Coa in enzyme-linked immunosorbent assay-type binding experiments. Sequence analyses revealed that this Coa region contained shorter segments with sequences similar to the Fg binding segments in Efb. An alanine scanning approach allowed us to identify the residues in Coa and Efb that are critical for Fg binding and to define the Fg binding motifs in the two proteins. In these motifs, the residues required for Fg binding are largely conserved, and they therefore constitute variants of a common Fg binding motif which binds to Fg with high affinity. Defining a specific motif also allowed us to identify a functional Fg binding register for the Coa repeats that is different from the repeat unit previously proposed.

IMPORTANCE
Staphylococcus aureus
infections are a major health problem that affects an estimated 50 million people globally and causes the death of about 20,000 Americans each year. A number of experimental vaccines have been developed during the past years. However, these vaccines have all failed in clinical trials. The ability of
S. aureus
to form an Fg shield surrounding and protecting bacterial cells from clearance may explain why the vaccines are failing. Furthermore,
S. aureus
coagulase can induce the formation of a fibrin(ogen) shield in experimental abscess models which surrounds and protects bacteria in the microcolony from clearance. In this study, we identified for the first time a microbial Fg binding motif. Variants of this motif are present in coagulase and Efb. Our results provide a molecular basis for the rational design of inhibitors that could potentially prevent the formation of the obstructing Fg shield.
Palliative care research centre's move into social media: constructing a framework for ethical research, a consensus paper
Authors: Hopewell-Kelly Noreen , Baillie Jessica , Sivell Stephanie , Harrop Emily , Bowyer Anna , Taylor Sophia , Thomas Kristen , Newman Alisha , Prout Hayley , Byrne Anthony , Taubert Mark , Nelson Annmarie 
Published: January 2016

BackgroundSocial media (SM) have altered the way we live and, for many, the way we die. The information available on even the rarest conditions is vast. Free from restrictions of mobility, time and distance, SM provides a space for people to share experiences of illness, death and dying, and potentially benefit from the emotional and practical support of others n similar positions. The communications that take place in these spaces also create large amounts of ‘data’ which, for any research centre, cannot be ignored. However, for a palliative care research centre the use of this ‘data’ comes with specific ethical dilemmas.MethodsThis paper details the process that we, as a research, went through in constructing a set of ethical guidelines by which to work. This involved conducting two consensus days; one with researchers from within the centre, and one with the inclusion of external researchers with a specific interest in SM.ResultsThe primary themes that emerged from the consensus meetings includes; SM as a public or private space; the status of open and closed groups; the use of historical data; recruiting participants and obtaining informed consent and problems of anonymity associated with dissemination.ConclusionsThese are the themes that this paper will focus on prior to setting out the guidelines that we subsequently constructed.
The relationship between oxidised LDL, endothelial progenitor cells and coronary endothelial function in patients with CHD
Authors: Watt Jonathan , Kennedy Simon , Ahmed Nadeem , Hayhurst James , McClure John D , Berry Colin , Wadsworth Roger M , Oldroyd Keith G 
Published: January 2016

ObjectiveThe balance between coronary endothelial dysfunction and repair is influenced by many protective and deleterious factors circulating in the blood. We studied the relationship between oxidised low-density lipoprotein (oxLDL), circulating endothelial progenitor cells (EPCs) and coronary endothelial function in patients with stable coronary heart disease (CHD).Methods33 patients with stable CHD were studied. Plasma oxLDL was measured using ELISA, coronary endothelial function was assessed using intracoronary acetylcholine infusion and EPCs were quantified using flow cytometry for CD34+/KDR+cells.ResultsPlasma oxLDL correlated positively with the number of EPCs in the blood (r=0.46, p=0.02). There was a positive correlation between the number of circulating EPCs and coronary endothelial function (r=0.42, p=0.04). There was no significant correlation between oxLDL and coronary endothelial function.ConclusionsPlasma levels of oxLDL are associated with increased circulating EPCs in the blood of patients with CHD, which may reflect a host-repair response to endothelial injury. Patients with stable CHD had a high prevalence of coronary endothelial dysfunction, which was associated with lower numbers of circulating EPCs, suggesting a mechanistic link between endothelial dysfunction and the pathogenesis of atherosclerosis.
Heme Iron Intake, Dietary Antioxidant Capacity, and Risk of Colorectal Adenomas in a Large Cohort Study of French Women
Authors: Bastide Nadia , Morois Sophie , Cadeau Claire , Kangas Suvi , Serafini Mauro , Gusto Gaëlle , Dossus Laure , Pierre Fabrice H. , Clavel-Chapelon Françoise , Boutron-Ruault Marie-Christine 
Published: January 2016

Abstract
Background: Nitrosylated and non-nitrosylated heme iron from red processed and nonprocessed meat have been associated with increased colorectal carcinogenesis. Mechanisms include oxidative processes. It has been hypothesized that dietary antioxidants could counteract the effects of heme iron. We investigated the relationships between heme iron intake and the risk of colorectal adenomas, and a potential interaction with the dietary antioxidant capacity, in the E3N prospective cohort study.
Methods: The study included 17,397 women, who underwent at least one colonoscopy. Among them, 1,409 were diagnosed with at least one first colorectal adenoma during the 103,253 person-years of follow-up. Dietary intake was measured by a semiquantitative food history questionnaire. HR estimates and 95% confidence intervals (CI) were obtained from Cox proportional hazards models, adjusted for potential confounders.
Results: Heme iron intake was positively associated with colorectal and colon adenoma risks [HR for the fourth vs. first quartile: HR4 = 1.36 (1.13–1.65), Ptrend = 0.001 and HR4 = 1.49; 95% CI, 1.19–1.87; Ptrend = 0.0003, respectively]. Nonnitrosylated and nitrosylated heme iron intakes were, respectively, associated with advanced distal and proximal adenoma risks. There was a dose–effect relationship between the heme iron to total dietary antioxidant capacity ratio and colorectal adenoma risk.
Conclusion: In this prospective cohort study, the association between heme iron and colorectal adenoma risk was found to depend on site, nitrosylation or not, and the ratio with the NEAC.
Impact: These results emphasize the need for a global assessment of diet when considering nutritional prevention of colorectal carcinogenesis. Cancer Epidemiol Biomarkers Prev; 25(4); 640–7. ©2016 AACR.