bluuebunny/crossref_metadata_2025 huggingface dataset:
Comparative Single-Cell Genomics of Chloroflexi from the Okinawa Trough Deep-Subsurface Biosphere
Authors: Fullerton Heather , Moyer Craig L.
Published: March 2016

Chloroflexi
small-subunit (SSU) rRNA gene sequences are frequently recovered from subseafloor environments, but the metabolic potential of the phylum is poorly understood. The phylum
Chloroflexi
is represented by isolates with diverse metabolic strategies, including anoxic phototrophy, fermentation, and reductive dehalogenation; therefore, function cannot be attributed to these organisms based solely on phylogeny. Single-cell genomics can provide metabolic insights into uncultured organisms, like the deep-subsurface
Chloroflexi
. Nine SSU rRNA gene sequences were identified from single-cell sorts of whole-round core material collected from the Okinawa Trough at Iheya North hydrothermal field as part of Integrated Ocean Drilling Program (IODP) expedition 331 (Deep Hot Biosphere). Previous studies of subsurface
Chloroflexi
single amplified genomes (SAGs) suggested heterotrophic or lithotrophic metabolisms and provided no evidence for growth by reductive dehalogenation. Our nine
Chloroflexi
SAGs (seven of which are from the order
Anaerolineales
) indicate that, in addition to genes for the Wood-Ljungdahl pathway, exogenous carbon sources can be actively transported into cells. At least one subunit for pyruvate ferredoxin oxidoreductase was found in four of the
Chloroflexi
SAGs. This protein can provide a link between the Wood-Ljungdahl pathway and other carbon anabolic pathways. Finally, one of the seven
Anaerolineales
SAGs contains a distinct reductive dehalogenase homologous (
rdhA
) gene.

IMPORTANCE
Through the use of single amplified genomes (SAGs), we have extended the metabolic potential of an understudied group of subsurface microbes, the
Chloroflexi
. These microbes are frequently detected in the subsurface biosphere, though their metabolic capabilities have remained elusive. In contrast to previously examined
Chloroflexi
SAGs, our genomes (several are from the order
Anaerolineales
) were recovered from a hydrothermally driven system and therefore provide a unique window into the metabolic potential of this type of habitat. In addition, a reductive dehalogenase gene (
rdhA
) has been directly linked to marine subsurface
Chloroflexi
, suggesting that reductive dehalogenation is not limited to the class
Dehalococcoidia
. This discovery expands the nutrient-cycling and metabolic potential present within the deep subsurface and provides functional gene information relating to this enigmatic group.
Development of a Real-Time PCR for a Sensitive One-Step Coprodiagnosis Allowing both the Identification of Carnivore Feces and the Detection of Toxocara spp. and Echinococcus multilocularis
Authors: Knapp Jenny , Umhang Gérald , Poulle Marie-Lazarine , Millon Laurence
Published: March 2016

Studying the environmental occurrence of parasites of concern for humans and animals based on coprosamples is an expanding field of work in epidemiology and the ecology of health. Detecting and quantifying
Toxocara
spp. and
Echinococcus multilocularis
, two predominant zoonotic helminths circulating in European carnivores, in feces may help to better target measures for prevention. A rapid, sensitive, and one-step quantitative PCR (qPCR) allowing detection of
E. multilocularis
and
Toxocara
spp. was developed in the present study, combined with a host fecal test based on the identification of three carnivores (red fox, dog, and cat) involved in the life cycles of these parasites. A total of 68 coprosamples were collected from identified specimens from
Vulpes vulpes
,
Canis lupus familiaris
,
Canis lupus
,
Felis silvestris catus
,
Meles meles
,
Martes foina
, and
Martes martes
. With DNA coprosamples, real-time PCR was performed in duplex with a qPCR inhibitor control specifically designed for this study. All the coprosample host identifications were confirmed by qPCR combined with sequencing, and parasites were detected and confirmed (
E. multilocularis
in red foxes and
Toxocara cati
in cats; 16% of samples presented inhibition). By combining parasite detection and quantification, the host fecal test, and a new qPCR inhibitor control, we created a technique with a high sensitivity that may considerably improve environmental studies of pathogens.
Cellar-Associated Saccharomyces cerevisiae Population Structure Revealed High-Level Diversity and Perennial Persistence at Sauternes Wine Estates
Authors: Börlin Marine , Venet Pauline , Claisse Olivier , Salin Franck , Legras Jean-Luc , Masneuf-Pomarede Isabelle
Published: March 2016

Three wine estates (designated A, B, and C) were sampled in Sauternes, a typical appellation of the Bordeaux wine area producing sweet white wine. From those wine estates, 551 yeast strains were collected between 2012 and 2014, added to 102 older strains from 1992 to 2011 from wine estate C. All the strains were analyzed through 15 microsatellite markers, resulting in 503 uniqueSaccharomyces cerevisiaegenotypes, revealing high genetic diversity and a low presence of commercial yeast starters. Population analysis performed usingFstgenetic distance or ancestry profiles revealed that the two closest wine estates, B and C, which have juxtaposed vineyard plots and common seasonal staff, share more related isolates with each other than with wine estate A, indicating exchange between estates. The characterization of isolates collected 23 years ago at wine estate C in relation to recent isolates obtained at wine estate B revealed the long-term persistence of isolates. Last, during the 2014 harvest period, a temporal succession of ancestral subpopulations related to the different batches associated with the selective picking of noble rotted grapes was highlighted.

IMPORTANCEHigh genetic diversity ofS. cerevisiaeisolates from spontaneous fermentation on wine estates in the Sauternes appellation of Bordeaux was revealed. Only 7% of all Sauternes strains were considered genetically related to specific commercial strains. The long-term persistence (over 20 years) ofS. cerevisiaeprofiles on a given wine estate is highlighted.
Biological Low-pH Mn(II) Oxidation in a Manganese Deposit Influenced by Metal-Rich Groundwater
Authors: Bohu Tsing , Akob Denise M. , Abratis Michael , Lazar Cassandre S. , Küsel Kirsten
Published: March 2016

The mechanisms, key organisms, and geochemical significance of biological low-pH Mn(II) oxidation are largely unexplored. Here, we investigated the structure of indigenous Mn(II)-oxidizing microbial communities in a secondary subsurface Mn oxide deposit influenced by acidic (pH 4.8) metal-rich groundwater in a former uranium mining area. Microbial diversity was highest in the Mn deposit compared to the adjacent soil layers and included the majority of known Mn(II)-oxidizing bacteria (MOB) and two genera of known Mn(II)-oxidizing fungi (MOF). Electron X-ray microanalysis showed that romanechite [(Ba,H
2
O)
2
(Mn
4+
,Mn
3+
)
5
O
10
] was conspicuously enriched in the deposit. Canonical correspondence analysis revealed that certain fungal, bacterial, and archaeal groups were firmly associated with the autochthonous Mn oxides. Eight MOB within the
Proteobacteria
,
Actinobacteria
, and
Bacteroidetes
and one MOF strain belonging to
Ascomycota
were isolated at pH 5.5 or 7.2 from the acidic Mn deposit. Soil-groundwater microcosms demonstrated 2.5-fold-faster Mn(II) depletion in the Mn deposit than adjacent soil layers. No depletion was observed in the abiotic controls, suggesting that biological contribution is the main driver for Mn(II) oxidation at low pH. The composition and species specificity of the native low-pH Mn(II) oxidizers were highly adapted to
in situ
conditions, and these organisms may play a central role in the fundamental biogeochemical processes (e.g., metal natural attenuation) occurring in the acidic, oligotrophic, and metalliferous subsoil ecosystems.

IMPORTANCE
This study provides multiple lines of evidence to show that microbes are the main drivers of Mn(II) oxidation even at acidic pH, offering new insights into Mn biogeochemical cycling. A distinct, highly adapted microbial community inhabits acidic, oligotrophic Mn deposits and mediates biological Mn oxidation. These data highlight the importance of biological processes for Mn biogeochemical cycling and show the potential for new bioremediation strategies aimed at enhancing biological Mn oxidation in low-pH environments for contaminant mitigation.
Overproduction of Magnetosomes by Genomic Amplification of Biosynthesis-Related Gene Clusters in a Magnetotactic Bacterium
Authors: Lohße Anna , Kolinko Isabel , Raschdorf Oliver , Uebe René , Borg Sarah , Brachmann Andreas , Plitzko Jürgen M. , Müller Rolf , Zhang Youming , Schüler Dirk
Published: March 2016

Magnetotactic bacteria biosynthesize specific organelles, the magnetosomes, which are membrane-enclosed crystals of a magnetic iron mineral that are aligned in a linear chain. The number and size of magnetosome particles have to be critically controlled to build a sensor sufficiently strong to ensure the efficient alignment of cells within Earth's weak magnetic field while at the same time minimizing the metabolic costs imposed by excessive magnetosome biosynthesis. Apart from their biological function, bacterial magnetosomes have gained considerable interest since they provide a highly useful model for prokaryotic organelle formation and represent biogenic magnetic nanoparticles with exceptional properties. However, potential applications have been hampered by the difficult cultivation of these fastidious bacteria and their poor yields of magnetosomes. In this study, we found that the size and number of magnetosomes within the cell are controlled by many different Mam and Mms proteins. We present a strategy for the overexpression of magnetosome biosynthesis genes in the alphaproteobacterium
Magnetospirillum gryphiswaldense
by chromosomal multiplication of individual and multiple magnetosome gene clusters via transposition. While stepwise amplification of the
mms6
operon resulted in the formation of increasingly larger crystals (increase of ∼35%), the duplication of all major magnetosome operons (
mamGFDC
,
mamAB
,
mms6
, and
mamXY
, comprising 29 genes in total) yielded an overproducing strain in which magnetosome numbers were 2.2-fold increased. We demonstrate that the tuned expression of the
mam
and
mms
clusters provides a powerful strategy for the control of magnetosome size and number, thereby setting the stage for high-yield production of tailored magnetic nanoparticles by synthetic biology approaches.

IMPORTANCE
Before our study, it had remained unknown how the upper sizes and numbers of magnetosomes are genetically regulated, and overproduction of magnetosome biosynthesis had not been achieved, owing to the difficulties of large-scale genome engineering in the recalcitrant magnetotactic bacteria. In this study, we established and systematically explored a strategy for the overexpression of magnetosome biosynthesis genes by genomic amplification of single and multiple magnetosome gene clusters via sequential chromosomal insertion by transposition. Our findings also indicate that the expression levels of magnetosome proteins together limit the upper size and number of magnetosomes within the cell. We demonstrate that tuned overexpression of magnetosome gene clusters provides a powerful strategy for the precise control of magnetosome size and number.
Control of Legionella Contamination and Risk of Corrosion in Hospital Water Networks following Various Disinfection Procedures
Authors: Marchesi Isabella , Ferranti Greta , Mansi Antonella , Marcelloni Anna M. , Proietto Anna R. , Saini Navneet , Borella Paola , Bargellini Annalisa
Published: March 2016

Physical and chemical disinfection methods have been proposed with the aim of controlling
Legionella
water contamination. To date, the most effective procedures for reducing bacterial contamination have not yet been defined. The aim of this study was to assess the long-term effectiveness of various disinfection procedures in order to reduce both culturable and nonculturable (NC) legionellae in different hospital water networks treated with heat, chlorine dioxide, monochloramine, and hydrogen peroxide. The temperature levels and biocide concentrations that proved to give reliable results were analyzed. In order to study the possible effects on the water pipes, we verified the extent of corrosion on experimental coupons after applying each method for 6 months. The percentage of positive points was at its lowest after treatment with monochloramine, followed by chlorine dioxide, hydrogen peroxide, and hyperthermia. Different selections of
Legionella
spp. were observed, as networks treated with chlorine-based disinfectants were contaminated mainly by
Legionella pneumophila
serogroup 1, hyperthermia was associated with serogroups 2 to 14, and hydrogen peroxide treatment was associated mainly with non-
pneumophila
species. NC cells were detected only in heat-treated waters, and also when the temperature was approximately 60°C. The corrosion rates of the coupons were within a satisfactory limit for water networks, but the morphologies differed. We confirm here that chemical disinfection controls
Legionella
colonization more effectively than hyperthermia does. Monochloramine was the most effective treatment, while hydrogen peroxide may be a promising alternative to chlorine-based disinfectants due to its ability to select for other, less virulent or nonpathogenic species.
Recognition of Histo-Blood Group Antigen-Like Carbohydrates in Lettuce by Human GII.4 Norovirus
Authors: Gao Xiang , Esseili Malak A. , Lu Zhongyan , Saif Linda J. , Wang Qiuhong
Published: March 2016

Human norovirus (HuNoV) genogroup II genotype 4 (GII.4) strains account for about 80% of the gastroenteritis outbreaks in the United States. Contaminated food is a major transmission vehicle for this virus. In humans, pigs, and oysters, histo-blood group antigens (HBGAs) act as attachment factors for HuNoVs. In lettuce, although the virus-like particles (VLPs) of a GII.4 HuNoV were found to bind to cell wall carbohydrates, the exact binding site has not been investigated. Here, we show the presence of HBGA-like carbohydrates in the cell wall of lettuce. The digestion of lettuce leaves with cell wall-degrading enzymes exposed more binding sites and significantly increased the level of binding of GII.4 HuNoV VLPs. Competition assays showed that both the HBGA monoclonal antibody, recognizing the H type, and plant lectins, recognizing α-
l
-fucose in the H type, effectively inhibited VLP binding to lettuce tissues. Lettuce cell wall components were isolated and their NoV VLP binding characteristics were tested by enzyme-linked immunosorbent assays. The binding was inhibited by pretreatment of the lettuce cell wall materials with α-1,2-fucosidase. Collectively, our results indicate that H-type HBGA-like carbohydrates exist in lettuce tissues and that GII.4 HuNoV VLPs can bind the exposed fucose moiety, possibly in the hemicellulose component of the cell wall.

IMPORTANCE
Salad crops and fruits are increasingly recognized as vehicles for human norovirus (HuNoV) transmission. A recent study showed that HuNoVs specifically bind to the carbohydrates of the lettuce cell wall. Histo-blood group antigens (HBGAs) are carbohydrates and are known as the attachment factors for HuNoV infection in humans. In this study, we show the presence of HBGA-like carbohydrates in lettuce, to which HuNoVs specifically bind. These results suggest that specifically bound HuNoVs cannot be removed by simple washing, which may allow viral transmission to consumers. Our findings provide new information needed for developing potential inhibitors to block binding and prevent contamination.
Application of a Euryarchaeota-Specific Helicase from Thermococcus kodakarensis for Noise Reduction in PCR
Authors: Fujiwara Ayako , Kawato Katsuhiro , Kato Saori , Yasukawa Kiyoshi , Hidese Ryota , Fujiwara Shinsuke
Published: March 2016

DNA/RNA helicases, which are enzymes for eliminating hydrogen bonds between bases of DNA/DNA, DNA/RNA, and RNA/RNA using the energy of ATP hydrolysis, contribute to various biological activities. In the present study, the
Euryarchaeota
-specific helicase EshA (TK0566) from the hyperthermophilic archaeon
Thermococcus kodakarensis
(
Tk
-EshA) was obtained as a recombinant form, and its enzymatic properties were examined.
Tk
-EshA exhibited maximal ATPase activity in the presence of RNA at 80°C. Unwinding activity was evaluated with various double-stranded DNAs (forked, 5′ overhung, 3′ overhung, and blunt end) at 50°C.
Tk
-EshA unwound forked and 3′ overhung DNAs. These activities were expected to unwind the structured template and to peel off misannealed primers when
Tk
-EshA was added to a PCR mixture. To examine the effect of
Tk
-EshA on PCR, various target DNAs were selected, and DNA synthesis was investigated. When 16S rRNA genes were used as a template, several misamplified products (noise DNAs) were detected in the absence of
Tk
-EshA. In contrast, noise DNAs were eliminated in the presence of
Tk
-EshA. Noise reduction by
Tk
-EshA was also confirmed when
Taq
DNA polymerase (a family A DNA polymerase, PolI type) and KOD DNA polymerase (a family B DNA polymerase, α type) were used for PCR. Misamplified bands were also eliminated during
toxA
gene amplification from
Pseudomonas aeruginosa
DNA, which possesses a high GC content (69%).
Tk
-EshA addition was more effective than increasing the annealing temperature to reduce misamplified DNAs during
toxA
amplification.
Tk
-EshA is a useful tool to reduce noise DNAs for accurate PCR.

IMPORTANCE
PCR is a technique that is useful for genetic diagnosis, genetic engineering, and detection of pathogenic microorganisms. However, troubles with nonspecific DNA amplification often occur from primer misannealing. In order to achieve a specific DNA amplification by eliminating noise DNAs derived from primer misannealing, a thermostable
Euryarchaeota
-specific helicase (
Tk
-EshA) was included in the PCR mixture. The addition of
Tk
-EshA has reduced noise DNAs in PCR.
Night-to-night variation of pulse oximetry in children with sleep-disordered breathing
Authors: Burke Rachael M , Maxwell Barbara , Hunter Carolyn , Graham David , O'Donoghue Dara , Shields Michael D
Published: March 2016

Background

Sleep-disordered breathing is a common and serious feature of many paediatric conditions and is particularly a problem in children with Down syndrome. Overnight pulse oximetry is recommended as an initial screening test, but it is unclear how overnight oximetry results should be interpreted and how many nights should be recorded.

Methods

This retrospective observational study evaluated night-to-night variation using statistical measures of repeatability for 214 children referred to a paediatric respiratory clinic, who required overnight oximetry measurements. This included 30 children with Down syndrome. We measured length of adequate trace, basal SpO2, number of desaturations (>4% SpO2 drop for >10 s) per hour (‘adjusted index’) and time with SpO2<90%. We classified oximetry traces into normal or abnormal based on physiology.

Results

132 out of 214 (62%) children had three technically adequate nights’ oximetry, including 13 out of 30 (43%) children with Down syndrome. Intraclass correlation coefficient for adjusted index was 0.54 (95% CI 0.20 to 0.81) among children with Down syndrome and 0.88 (95% CI 0.84 to 0.91) for children with other diagnoses. Negative predictor value of a negative first night predicting two subsequent negative nights was 0.2 in children with Down syndrome and 0.55 in children with other diagnoses.

Conclusions

There is substantial night-to-night variation in overnight oximetry readings among children in all clinical groups undergoing overnight oximetry. This is a more pronounced problem in children with Down syndrome. Increasing the number of attempted nights’ recording from one to three provides useful additional clinical information.
Review of the Local Organizing Committee (LOC) medical services during the 12th FINA World Swimming Championships (25 m) in Doha, Qatar
Authors: Dijkstra H Paul , Geertsema Liesel , Benzarti Nejib , van Dorssen Elsbeth A L , van den Hoogenband Cees-Rein , Mountjoy Margo
Published: March 2016

Background

One of the primary roles of Fédération Internationale de Natation (FINA) is to promote athlete health. The planning and delivery of major international event medical services is carried out in collaboration with the Local Organizing Committee Medical Commission (LOCMC). Aspetar Orthopaedic and Sports Medicine Hospital provided the medical services to the 12th FINA World Swimming Championships (25 m) creating a unique opportunity for collaboration with FINA.

Aim

The purpose of this paper is to review the planning and delivery of medical services and athlete health promotion projects during the 12th FINA World Swimming Championships (25 m) to facilitate the planning of future sporting events of this size and scope.

Methods

The 12th FINA World Swimming Championships (25 m) hosted 974 athletes from 166 countries. The LOC medical team recorded all medical encounters—newly incurred (or acute exacerbations of chronic) injuries and illnesses as well as follow-up consultations.

Results

More than 90% of teams did not travel with a team physician and relied on the LOCMC for diagnosis and treatment of injuries and illnesses in athletes and accredited team officials. The LOC medical team had a total of 554 medical encounters: 385 therapy, 34 athlete injury, 65 athlete illness and 70 non-athlete encounters.

Conclusions

The LOCMC in collaboration with FINA delivered comprehensive medical services to athletes, officials and spectators attending the 12th FINA World Swimming Championships (25 m). This review paper provides information relevant to the planning and delivery of LOCMC medical services for future international swimming events contributing to the FINA objective of promoting athlete health.
Incidence and aetiology of acute injuries during competitive road cycling
Authors: Decock Mathieu , De Wilde Lieven , Vanden Bossche Luc , Steyaert Adelheid , Van Tongel Alexander
Published: March 2016

Introduction

Despite the ever-increasing popularity of bicycle racing, the high perceived risk of acute injuries and the recent media attention, studies of acute injuries in road cyclists are rather scarce. The goal of this study is to evaluate the incidence, aetiology and patterns of acute injuries in non-professional competitive road cyclists during cycling races in Flanders.

Material and methods

All acute injuries that occurred during competition in Flanders in 2002 and 2012, collected in the injury registry, were analysed. The incidence, injury rate, diagnosis, circumstances and level of performance were evaluated.

Results

A total of 777 documented reports of accidents (1230 injuries) were retrieved for the years 2002 and 2012. There was no significant difference between incidence and injury rate between 2002 and 2012. There was a strong significant difference in the incidence between the different levels of performance in both seasons. Severe injuries were seen in 29.5% in 2002 and in 30.1% in 2012. The most common location of a severe injury was the hand. Collision with another rider was the most common cause of injury.

Conclusions

Almost 1 out of 6 non-professional competitive road cyclists had an accident during cycling races in 2002 and 2012 in Flanders and collision with other riders was the most important cause of a crash. The most common lesion was abrasion, but almost one out of three riders had a severe injury.
The effects of shifting tasks from pharmacy to non-pharmacy personnel for providing antiretroviral therapy to people living with HIV: a systematic review protocol
Authors: Mbeye Nyanyiwe M , Kredo Tamara , Wiysonge Charles S
Published: March 2016

Introduction

Shifting selected antiretroviral therapy (ART) tasks from specialised healthcare workers to those with shorter or less formal training has been implemented in resource-limited settings to alleviate critical shortages of human resources for health. However, the specifics of shifting ART dispensing from pharmacy to non-pharmacy personnel have not been addressed in a systematic review, although this can potentially increase access to ART. We will assess the effects of shifting dispensing and distribution of ART and adherence assessment from pharmacy to non-pharmacy personnel in low and middle-income countries.

Methods and analysis

We will search PubMed, CENTRAL, EMBASE, WHO Global Health Library and relevant grey literature for eligible controlled trials. Two authors will screen the search output, select eligible studies, assess risk of bias and extract data from included studies, resolving discrepancies by discussion and consensus. We will perform meta-analysis using both fixed and random effects models, investigate clinical and statistical heterogeneity, and assess our confidence in the overall evidence using standard Cochrane methods, including GRADE.

Ethics and dissemination

Only secondary data will be included in this review and ethics approval is not required. We will disseminate the review findings in various scientific fora, including peer-reviewed journals. The findings may help to inform policy makers in defining the scope of work of healthcare workers, and global recommendations for shifting the dispensing and distribution of ART from pharmacy to non-pharmacy personnel.

Trial registration number

CRD42015017034.
Role of students’ context in predicting academic performance at a medical school: a retrospective cohort study
Authors: Thiele Tamara , Pope Daniel , Singleton A , Stanistreet D
Published: March 2016

Objectives

This study examines associations between medical students’ background characteristics (postcode-based measures of disadvantage, high school attended, sociodemographic characteristics), and academic achievement at a Russell Group University.

Design

Retrospective cohort analysis.

Setting

Applicants accepted at the University of Liverpool medical school between 2004 and 2006, finalising their studies between 2010 and 2011.

Participants

571 students (with an English home postcode) registered on the full-time Medicine and Surgery programme, who successfully completed their medical degree.

Main outcome measures

Final average at year 4 of the medical programme (represented as a percentage).

Results

Entry grades were positively associated with final attainment (p<0.001). Students from high-performing schools entered university with higher qualifications than students from low-performing schools (p<0.001), though these differences did not persist at university. Comprehensive school students entered university with higher grades than independent school students (p<0.01), and attained higher averages at university, though differences were not significant after controlling for multiple effects. Associations between school type and achievement differed between sexes. Females attained higher averages than males at university. Significant academic differences were observed between ethnic groups at entry level and university. Neither of the postcode-based measures of disadvantage predicted significant differences in attainment at school or university.

Conclusions

The findings of this study suggest that educational attainment at school is a good, albeit imperfect, predictor of academic attainment at medical school. Most attainment differences observed between students either decreased or disappeared during university. Unlike previous studies, independent school students did not enter university with the highest grades, but achieved the lowest attainment at university. Such variations depict how patterns may differ between subjects and higher-education institutions. Findings advocate for further evidence to help guide the implementation of changes in admissions processes and widen participation at medical schools fairly.
Measurement of Exercise Tolerance before Surgery (METS) study: a protocol for an international multicentre prospective cohort study of cardiopulmonary exercise testing prior to major non-cardiac surgery
Authors: Wijeysundera Duminda N , Pearse Rupert M , Shulman Mark A , Abbott Tom E F , Torres Elizabeth , Croal Bernard L , Granton John T , Thorpe Kevin E , Grocott Michael P W , Farrington Catherine , Myles Paul S , Cuthbertson Brian H
Published: March 2016

Introduction

Preoperative functional capacity is considered an important risk factor for cardiovascular and other complications of major non-cardiac surgery. Nonetheless, the usual approach for estimating preoperative functional capacity, namely doctors’ subjective assessment, may not accurately predict postoperative morbidity or mortality. 3 possible alternatives are cardiopulmonary exercise testing; the Duke Activity Status Index, a standardised questionnaire for estimating functional capacity; and the serum concentration ofN-terminal pro-B-type natriuretic peptide (NT pro-BNP), a biomarker for heart failure and cardiac ischaemia.

Methods and analysis

The Measurement of Exercise Tolerance before Surgery (METS) Study is a multicentre prospective cohort study of patients undergoing major elective non-cardiac surgery at 25 participating study sites in Australia, Canada, New Zealand and the UK. We aim to recruit 1723 participants. Prior to surgery, participants undergo symptom-limited cardiopulmonary exercise testing on a cycle ergometer, complete the Duke Activity Status Index questionnaire, undergo blood sampling to measure serum NT pro-BNP concentration and have their functional capacity subjectively assessed by their responsible doctors. Participants are followed for 1 year after surgery to assess vital status, postoperative complications and general health utilities. The primary outcome is all-cause death or non-fatal myocardial infarction within 30 days after surgery, and the secondary outcome is all-cause death within 1 year after surgery. Both receiver-operating-characteristic curve methods and risk reclassification table methods will be used to compare the prognostic accuracy of preoperative subjective assessment, peak oxygen consumption during cardiopulmonary exercise testing, Duke Activity Status Index scores and serum NT pro-BNP concentration.

Ethics and dissemination

The METS Study has received research ethics board approval at all sites. Participant recruitment began in March 2013, and 1-year follow-up is expected to finish in 2016. Publication of the results of the METS Study is anticipated to occur in 2017.
Associations of cigarette smoking, betel quid chewing and alcohol consumption with high-sensitivity C-reactive protein in early radiographic knee osteoarthritis: a cross-sectional study
Authors: Zhang Yi , Zeng Chao , Wei Jie , Li Hui , Yang Tuo , Yang Ye , Deng Zhen-han , Ding Xiang , Lei Guanghua
Published: March 2016

Objectives

High-sensitivity C-reactive protein (hsCRP) is possibly related to osteoarthritis (OA) progression and a variety of OA-related symptoms. This study aimed to examine associations between cigarette smoking, betel quid chewing and alcohol consumption and hsCRP in early radiographic knee OA.

Design

Cross-sectional health examination survey.

Setting

This primary study was conducted in a health examination centre in China.

Participants

936 (656 men and 280 women) patients with early radiographic knee OA were included in this cross-sectional study.

Primary and secondary outcome measures

Smoking status was classified into four levels based on daily smoking habit: 0/day, 1–10/day, 11–20/day and >20/day. Betel quid chewing and alcohol consumption status was divided into ‘Yes’ or ‘No’. Early radiographic knee OA was defined as Kellgren Lawrence (K-L) grade 1 or 2 in at least one leg, and elevated hsCRP was assessed as ≥3.0 mg/L.

Results

After adjustment for a number of potential confounding factors, a significant positive association between cigarette smoking and hsCRP was observed in the multivariable model. The multivariable-adjusted ORs (95% CI) of elevated hsCRP (≥3.0 mg/L) in the second (1–10/day, n=133), third (11–20/day, n=59) and highest (>20/day, n=104) cigarette smoking categories were 1.54 (95% CI 0.91 to 2.61), 1.27 (95% CI 0.57 to 2.79) and 2.09 (95% CI 1.20 to 3.64), respectively, compared with the non-smoker category (n=640). In addition, there was a positive dose–response relationship between cigarette smoking and elevated hsCRP (p for trend=0.01). No significant associations between betel quid chewing and alcohol consumption and hsCRP were observed in the multivariable model.

Conclusions

This study indicated that cigarette smoking was positively associated with serum hsCRP level in patients with early radiographic knee OA. However, in view of the nature of cross-sectional designs, the results need to be confirmed by further prospective studies.
Is the peripapillary retinal perfusion related to myopia in healthy eyes? A prospective comparative study
Authors: Wang Xiaolei , Kong Xiangmei , Jiang Chunhui , Li Mengwei , Yu Jian , Sun Xinghuai
Published: March 2016

Objectives

The aim of this study was to evaluate the peripapillary and parafoveal perfusion of young, healthy myopic subjects with spectral domain optical coherence tomography (OCT) angiography.

Design

A prospective comparative study was conducted from December 2014 to January 2015.

Setting

Participants recruited from a population-based study performed by the Eye, Ear, Nose and Throat Hospital of Fudan University in Shanghai.

Participants

A total of 78 Chinese normal subjects (78 eyes) with different refraction were included. Myopia was divided into 4 groups on the basis of the refractive status: 20 eyes with emmetropia (mean spherical equivalent (MSE) 0.50D to −0.50D), 20 eyes with mild myopia (MSE −0.75D to −2.75D), 20 eyes with moderate myopia (MSE −3.00D to −5.75D), and 18 eyes with high myopia (MSE≤−6.00D).

Main outcome measures

Peripapillary and parafoveal retinal and choroidal perfusion parameters and their relationships with axial length (AL) and retinal nerve fibre layer (RNFL) thickness were analysed.

Results

Significant differences were found for the retinal flow index and vessel density in the peripapillary area among the 4 groups, but not in the parafoveal area. The high myopia group had the lowest peripapillary retinal flow index and vessel density. In addition, there was a negative correlation (β=−0.002, p=0.047) between the AL and peripapillary retinal flow index and a positive correlation between RNFL thickness and the peripapillary retinal perfusion parameters (flow index: β=0.001, p=0.006; vessel density: β=0.350, p=0.002) even after adjustment for other variables.

Conclusions

Highly myopic eyes have a decreased peripapillary retinal perfusion compared with emmetropic eyes. Such vascular features might increase the susceptibility to vascular-related eye diseases.
The expression of arginase-1, keratin (K) 8 and K18 in combined hepatocellular-cholangiocarcinoma, subtypes with stem-cell features, intermediate-cell type
Authors: Akiba Jun , Nakashima Osamu , Hattori Satoshi , Naito Yoshiki , Kusano Hironori , Kondo Reiichiro , Nakayama Masamichi , Tanikawa Ken , Todoroki Keita , Umeno Yumi , Nakamura Ken , Sanada Sakiko , Yamaguchi Rin , Ogasawara Sachiko , Yano Hirohisa
Published: March 2016

Aims

The WHO classification describes that combined hepatocellular-cholangiocarcinoma, subtypes with stem-cell features, intermediate-cell subtype (CHC-INT) is composed of tumour cells with features intermediate between hepatocytes and cholangiocytes. However, we previously reported that CHC-INT showed a high positive rate of biliary markers, but the expression of hepatocyte paraffin (HepPar)-1 was low. In this study, we examined the expression of other hepatocyte markers, such as arginase-1 (Arg-1), keratin (K) 8 and K18 in CHC-INT in order to examine the utility of pathological diagnosis in CHC-INT.

Methods

We performed immunohistochemistry (IHC) of Arg-1, K8 and K18 using 32 previously diagnosed as CHC-INT. Immunoreactivity was evaluated with grading from 0 to 4 according to the distribution area of positive cells. The obtained findings of Arg-1, K8 and K18 were compared with those of K7, K19 and HepPar-1.

Results

Out of the 32 cases, 22 (68.8%) cases were positive for Arg-1. Twenty-five (78.1%) were positive for K8. The IHC scores of Arg-1 and K8 were significantly higher than those of HepPar-1, but significantly lower than those of K7 and K19. The K18 expression was widely observed in all cases (100%). The IHC score of Arg-1 and K8 in CHC-INT was intermediate between hepatocellular carcinoma and cholangiocarcinoma.

Conclusions

Arg-1 and K8 were good markers to identify intermediate cells between hepatocytes and cholangiocytes. These can be useful markers for pathological diagnosis of CHC-INT, which usually has wide histological diversities, in combination with other hepatocytic and/or cholangiocytic markers.
Left ventricular assist device: a bridge to transplant or destination therapy?
Authors: Patel Swati , Nicholson Louise , Cassidy Christopher J , Wong Kenneth Y-K
Published: March 2016

Heart failure is a major problem worldwide; it is the leading cause of hospitalisation and is posing a huge financial burden. Advances in healthcare have contributed to increased life expectancy, with a resultant increase in the number of patients with chronic heart failure. For many patients who are still severely symptomatic despite optimal medical therapy and cardiac resynchronisation therapy, cardiac transplantation would be the preferred treatment option. However, hopes are cut short with a limited donor pool of hearts for the increasing number of patients requiring cardiac transplantation. One uprising method to fill this treatment void for patients with advanced end-stage heart failure (ESHF) is the Left Ventricular Assist Device (LVAD). Although traditionally used as a bridge to transplantation, owing to limitation of suitable donors, evidence suggests increasing potential for the use of LVAD as destination therapy (DT), that is, lifelong permanent support. Exploration of DT is a promising avenue to many patients suffering with ESHF who may never be fortunate enough to receive a heart transplant, but not without reservations of its efficacy, safety, effects on quality-adjusted life years and cost-effectiveness, especially in comparison to heart transplantation.
Decision‐tree analysis of clinical data to aid diagnostic reasoning for equine laminitis: a cross‐sectional study
Authors: Wylie C. E. , Shaw D. J. , Verheyen K. L. P. , Newton J. R.
Published: March 2016

The objective of this cross‐sectional study was to compare the prevalence of selected clinical signs in laminitis cases and non‐laminitic but lame controls to evaluate their capability to discriminate laminitis from other causes of lameness. Participating veterinary practitioners completed a checklist of laminitis‐associated clinical signs identified by literature review. Cases were defined as horses/ponies with veterinary‐diagnosed, clinically apparent laminitis; controls were horses/ponies with any lameness other than laminitis. Associations were tested by logistic regression with adjusted odds ratios (ORs) and 95% confidence intervals, with veterinary practice as an a priori fixed effect. Multivariable analysis using graphical classification tree‐based statistical models linked laminitis prevalence with specific combinations of clinical signs. Data were collected for 588 cases and 201 controls. Five clinical signs had a difference in prevalence of greater than +50 per cent: ‘reluctance to walk’ (OR 4.4), ‘short, stilted gait at walk’ (OR 9.4), ‘difficulty turning’ (OR 16.9), ‘shifting weight’ (OR 17.7) and ‘increased digital pulse’ (OR 13.2) (all P<0.001). ‘Bilateral forelimb lameness’ was the best discriminator; 92 per cent of animals with this clinical sign had laminitis (OR 40.5, P<0.001). If, in addition, horses/ponies had an ‘increased digital pulse’, 99 per cent were identified as laminitis. ‘Presence of a flat/convex sole’ also significantly enhanced clinical diagnosis discrimination (OR 15.5, P<0.001). This is the first epidemiological laminitis study to use decision‐tree analysis, providing the first evidence base for evaluating clinical signs to differentially diagnose laminitis from other causes of lameness. Improved evaluation of the clinical signs displayed by laminitic animals examined by first‐opinion practitioners will lead to equine welfare improvements.
Low volume-fraction microstructures in martensites and crystal plasticity
Authors: Conti Sergio , Zwicknagl Barbara
Published: March 2016

We study microstructure formation in two nonconvex singularly-perturbed variational problems from materials science, one modeling austenite–martensite interfaces in shape-memory alloys, the other one slip structures in the plastic deformation of crystals. For both functionals we determine the scaling of the optimal energy in terms of the parameters of the problem, leading to a characterization of the mesoscopic phase diagram. Our results identify the presence of a new phase, which is intermediate between the classical laminar microstructures and branching patterns. The new phase, characterized by partial branching, appears for both problems in the limit of small volume fraction, that is, if one of the variants (or of the slip systems) dominates the picture and the volume fraction of the other one is small.
Induced vacuum bosonic current in a compactified cosmic string spacetime
Authors: Bragança E. A. F. , Santana Mota H. F. , de Mello E. R. Bezerra
Published: March 2016

We analyze the bosonic current densities induced by a magnetic flux running along an idealized cosmic string considering that the coordinate along its axis is compactified. We also consider the presence of a magnetic flux enclosed by the compactificatified axis. To develop this analysis, we calculate the complete set of normalized bosonic wave functions obeying a quasiperiodicity condition along the compactified dimension. We show that in this context only the azimuthal and axial currents take place.
Enhanced ethanol catabolism in orphan nuclear receptor SHP-null mice
Authors: Park Jung Eun , Lee Mikang , Mifflin Ryan , Lee Yoon Kwang
Published: March 2016

Deficiency of the orphan nuclear hormone receptor small heterodimer partner (SHP, NR0B2) protects mice from diet-induced hepatic steatosis, in part, via repression of peroxisome proliferator-activated receptor (PPAR)-γ2( Pparg2) gene expression. Alcoholic fatty liver diseases (AFLD) share many common pathophysiological features with non-AFLD. To study the role of SHP and PPARγ2in AFLD, we used a strategy of chronic ethanol feeding plus a single binge ethanol feeding to challenge wild-type (WT) and SHP-null (SHP−/−) mice with ethanol. The ethanol feeding induced liver fat accumulation and mRNA expression of hepatic Pparg2 in WT mice, which suggests that a high level of PPARγ2is a common driving force for fat accumulation induced by ethanol or a high-fat diet. Interestingly, ethanol-fed SHP−/−mice displayed hepatic fat accumulation similar to that of ethanol-fed WT mice, even though their Pparg2 expression level remained lower. Mortality of SHP−/−mice after ethanol binge feeding was significantly reduced and their acetaldehyde dehydrogenase ( Aldh2) mRNA level was higher than that of their WT counterparts. After an intoxicating dose of ethanol, SHP−/−mice exhibited faster blood ethanol clearance and earlier wake-up time than WT mice. Higher blood acetate, the end product of ethanol metabolism, and lower acetaldehyde levels were evident in the ethanol-challenged SHP−/−than WT mice. Ethanol-induced inflammatory responses and lipid peroxidation were also lower in SHP−/−mice. The current data show faster ethanol catabolism and extra fat storage through conversion of acetate to acetyl-CoA before its release into the circulation in this ethanol-feeding model in SHP−/−mice.
Liver-specific loss of Perilipin 2 alleviates diet-induced hepatic steatosis, inflammation, and fibrosis
Authors: Najt Charles P. , Senthivinayagam Subramanian , Aljazi Mohammad B. , Fader Kelly A. , Olenic Sandra D. , Brock Julienne R. L. , Lydic Todd A. , Jones A. Daniel , Atshaves Barbara P.
Published: March 2016

Hepatic inflammation and fibrosis are key elements in the pathogenesis of nonalcoholic steatohepatitis (NASH), a progressive liver disease initiated by excess hepatic lipid accumulation. Lipid droplet protein Perilipin 2 (Plin2) alleviates dietary-induced hepatic steatosis when globally ablated; however, its role in the progression of NASH remains unknown. To investigate this further, we challenged Plin2 liver-specific knockout mice (designated L-KO) and their respective wild-type (WT) controls with a methionine-choline-deficient (MCD) diet for 15 days to induce a NASH phenotype of increased hepatic triglyceride levels through impaired phosphatidylcholine (PC) synthesis and very-low-density lipoprotein (VLDL) secretion. Results on liver weights, body weights, fat tissue mass, and histology in WT and L-KO mice fed the MCD diet revealed signs of hepatic steatosis, fibrosis, and inflammation; however, these effects were blunted in L-KO mice. In addition, levels of PC and VLDL were unchanged, and hepatic steatosis was reduced in L-KO mice fed the MCD diet, due in part to an increase in remodeling of PE to PC via the enzyme phosphatidylethanolamine N-methyltransferase (PEMT). These mice also exhibited decreased hepatic expression of proinflammatory markers cyclooxygenase 2, IL-6, TNF-α, IL-1β, and reduced expression of endoplasmic reticulum (ER) stress proteins C/EBP homologous protein and cleaved caspase-1. Taken together, these results suggest that Plin2 liver-specific ablation alleviates diet-induced hepatic steatosis and inflammation via a PEMT-mediated mechanism that involves compensatory changes in proteins involved in phospholipid remodeling, inflammation, and ER stress that work to alleviate diet-induced NASH. Overall, these findings support a role for Plin2 as a target for NASH therapy.
Thrombospondin-4 knockout in hypertension protects small-artery endothelial function but induces aortic aneurysms
Authors: Palao Teresa , Rippe Catarina , van Veen Henk , VanBavel Ed , Swärd Karl , Bakker Erik N. T. P.
Published: March 2016

Thrombospondin-4 (TSP-4) is a multidomain calcium-binding protein that has both intracellular and extracellular functions. As an extracellular matrix protein, it is involved in remodeling processes. Previous work showed that, in the cardiovascular system, TSP-4 expression is induced in the heart in response to experimental pressure overload and infarction injury. Intracellularly, it mediates the endoplasmic reticulum stress response in the heart. In this study, we explored the role of TSP-4 in hypertension. For this purpose, wild-type and TSP-4 knockout ( Thbs4 −/−) mice were treated with angiotensin II (ANG II). Hearts from ANG II-treated Thbs4 −/− mice showed an exaggerated hypertrophic response. Interestingly, aortas from Thbs4 −/− mice treated with ANG II showed a high incidence of aneurysms. In resistance arteries, ANG II-treated wild-type mice showed impaired endothelial-dependent relaxation. This was not observed in ANG II-treated Thbs4 −/− mice or in untreated controls. No differences were found in the passive pressure-diameter curves or stress-strain relationships, although ANG II-treated Thbs4 −/− mice showed a tendency to be less stiff, associated with thicker diameters of the collagen fibers as revealed by electron microscopy. We conclude that TSP-4 plays a role in hypertension, affecting cardiac hypertrophy, aortic aneurysm formation, as well as endothelial-dependent relaxation in resistance arteries.