bluuebunny/crossref_metadata_2025 huggingface dataset:
Environmental and historical controls of floristic composition across the South American Dry Diagonal
Authors: Neves Danilo M. , Dexter Kyle G. , Pennington R. Toby , Bueno Marcelo L. , Oliveira Filho Ary T.
Published: May 2015

Aim

The aim of this study was to test the role of environmental factors and spatially autocorrelated processes, such as historical fragmentation and dispersal limitation, in driving floristic variation across seasonally dry tropical forests (SDTFs) in eastern South America.

Location

SDTFs extending from the Caatinga phytogeographical domain of north‐eastern Brazil to the Chaco phytogeographical domain of northern Argentina, an area referred to as the Dry Diagonal.

Methods

We compiled a database of 282 inventories of woody vegetation in SDTFs from across the Dry Diagonal and combined this with data for 14 environmental variables. We assessed the relative contribution of spatially autocorrelated processes and environmental factors to the floristic turnover among SDTFs across the Dry Diagonal using variation partitioning methods. In addition, we used multivariate analyses to determine which environmental factors were most important in explaining the turnover.

Results

We found that the environmental factors measured (temperature, precipitation and edaphic conditions) explained 21.3% of the variation in species composition, with 14.1% of this occurring independently of spatial autocorrelation. A spatially structured fraction of 4.2% could not be accounted for by the environmental factors measured. The main axis of compositional variation was significantly correlated with a north–south gradient in temperature regime. At the extreme south of the Dry Diagonal, a cold temperature regime, in which frost occurred, appeared to underlie floristic similarities between chaco woodlands and southern SDTFs.

Main conclusions

Environmental variables, particularly those related to temperature regime, seem to be the most significant factors affecting variation in species composition of SDTFs. Thus historical fragmentation and isolation alone cannot explain the turnover in species composition within SDTFs, as is often assumed. Compositional and environmental heterogeneity needs to be taken into account both to understand the past distribution of SDTFs and to manage and conserve this key tropical biome.
Contrasting population‐level responses to Pleistocene climatic oscillations in an alpine bat revealed by complete mitochondrial genomes and evolutionary history inference
Authors: Alberdi Antton , Gilbert M. Thomas P. , Razgour Orly , Aizpurua Ostaizka , Aihartza Joxerra , Garin Inazio
Published: May 2015

Aim

We used an integrative approach to reconstruct the evolutionary history of the alpine long‐eared bat, Plecotus macrobullaris, to test whether the variable effects of Pleistocene climatic oscillations across geographical regions led to contrasting population‐level demographic histories within a single species.

Location

The Western Palaearctic.

Methods

We sequenced the complete mitochondrial genomes of 57 individuals from across the distribution of the species. The analysis integrated ecological niche modelling (ENM), approximate Bayesian computation (ABC), measures of genetic diversity and Bayesian phylogenetic methods.

Results

We identified two deep lineages: a western lineage, restricted to the Pyrenees and the Alps, and an eastern lineage, which expanded across the mountain ranges east of the Dinarides (Croatia). ENM projections of past conditions predicted that climatic suitability was reduced during cold stages in the areas inhabited by the western lineage, while the opposite trend was observed in the mountains inhabited by the eastern lineage. The palaeodemographic scenario that best fitted our data is consistent with the western lineage population size having shrunk repeatedly because of the extensive glaciation events that occurred in the Alps and Pyrenees during the Pleistocene. In contrast, the eastern lineage maintained a constant population size as is consistent with more limited glaciation in the mountains of south‐eastern Europe and the Middle East.

Main conclusions

This study shows that the demographic response of populations to Pleistocene climatic oscillations depended on their geographical location, offering an example of population‐level variations in the effects and long‐term consequences of climate change.
Contrasting species and functional beta diversity in montane ant assemblages
Authors: Bishop Tom R. , Robertson Mark P. , van Rensburg Berndt J. , Parr Catherine L.
Published: May 2015

Aim

Beta diversity describes the variation in species composition between sites and can be used to infer why different species occupy different parts of the globe. It can be viewed in a number of ways. First, it can be partitioned into two distinct patterns: turnover and nestedness. Second, it can be investigated from either a species identity or a functional‐trait point of view. We aim to document for the first time how these two aspects of beta diversity vary in response to a large environmental gradient.

Location

Maloti‐Drakensberg Mountains, southern Africa.

Methods

We sampled ant assemblages along an extensive elevational gradient (900–3000 m a.s.l.) twice yearly for 7 years, and collected functional‐trait information related to the species’ dietary and habitat‐structure preferences. We used recently developed methods to partition species and functional beta diversity into their turnover and nestedness components. A series of null models were used to test whether the observed beta diversity patterns differed from random expectations.

Results

Species beta diversity was driven by turnover, but functional beta diversity was composed of both turnover and nestedness patterns at different parts of the gradient. Null models revealed that deterministic processes were likely to be responsible for the species patterns but that the functional changes were indistinguishable from stochasticity.

Main conclusions

Different ant species are found with increasing elevation, but they tend to represent an increasingly nested subset of the available functional strategies. This finding is unique and narrows down the list of possible factors that control ant existence across elevation. We conclude that diet and habitat preferences have little role in structuring ant assemblages in montane environments and that some other factor must be driving the non‐random patterns of species turnover. This finding also highlights the importance of distinguishing between different kinds of beta diversity.
Diagnosis of more gestational diabetes lead to better pregnancy outcomes: Comparing the International Association of the Diabetes and Pregnancy Study Group criteria, and the Carpenter and Coustan criteria
Authors: Wu En‐Tzu , Nien Feng‐Jung , Kuo Chun‐Heng , Chen Szu‐Chi , Chen Kuan‐Yu , Chuang Lee‐Ming , Li Hung‐Yuan , Lee Chien‐Nan
Published: May 2015

Aims/Introduction

The International Association of the Diabetes and Pregnancy Study Group (IADPSG) criteria for gestational diabetes are associated with increased prevalence. However, it remains unknown if intervention for more women with gestational diabetes mellitus by the IADPSG criteria results in better pregnancy outcomes than adopting the Carpenter and Coustan (C&C) criteria in Asian populations.

Materials and Methods

This was a retrospective cohort study. A total of 1,840 women, 952 subjects by the IADPSG criteria and 888 subjects by the C&C criteria, who delivered singletons in 2011 in a single tertiary center, were included in the study. The same therapeutic interventions were offered to women with gestational diabetes mellitus by the two criteria. Maternal and neonatal outcomes were evaluated.

Results

Adopting the IADPSG criteria increased the prevalence of gestational diabetes mellitus diagnosis to 13.44%, compared with 2.59% by the C&C criteria. The diagnosis was made 3 weeks earlier by the IADPSG criteria (27 vs 30.5 weeks, P < 0.0001). Adopting the IADPSG criteria was associated with reduced risk of primary cesarean section (adjusted odds ratio 0.79, 95% confidence interval 0.63–0.998, P < 0.05) and having any one of the adverse fetal outcomes (adjusted odds ratio 0.79, 95% confidence interval 0.64–0.998, P < 0.05), including birthweight >90th percentile, jaundice, admission to neonatal intensive care unit, birth trauma, neonatal hypoglycemia and fetal death.

Conclusions

Adopting the IADPSG criteria is associated with improved pregnancy outcomes, at the expense of increased prevalence of gestational diabetes mellitus diagnosis.
Manganese homeostasis in the nervous system
Authors: Chen Pan , Chakraborty Sudipta , Mukhopadhyay Somshuvra , Lee Eunsook , Paoliello Monica M. B. , Bowman Aaron B. , Aschner Michael
Published: May 2015

Manganese (Mn) is an essential heavy metal that is naturally found in the environment. Daily intake through dietary sources provides the necessary amount required for several key physiological processes, including antioxidant defense, energy metabolism, immune function and others. However, overexposure from environmental sources can result in a condition known as manganism that features symptomatology similar to Parkinson's disease (PD). This disorder presents with debilitating motor and cognitive deficits that arise from a neurodegenerative process. In order to maintain a balance between its essentiality and neurotoxicity, several mechanisms exist to properly buffer cellular Mn levels. These include transporters involved in Mn uptake, and newly discovered Mn efflux mechanisms. This review will focus on current studies related to mechanisms underlying Mn import and export, primarily the Mn transporters, and their function and roles in Mn‐induced neurotoxicity.

image

Though and essential metal, overexposure to manganese may result in neurodegenerative disease analogous to Parkinson's disease. Manganese homeostasis is tightly regulated by transporters, including transmembrane importers (divalent metal transporter 1, transferrin and its receptor, zinc transporters ZIP8 and Zip14, dopamine transporter, calcium channels, choline transporters and citrate transporters) and exporters (ferroportin and SLC30A10), as well as the intracellular trafficking proteins (SPCA1 and ATP12A2). A manganese‐specific sensor, GPP130, has been identified, which affords means for monitoring intracellular levels of this metal.
A Comparison of Human Narrative Coding of Redemption and Automated Linguistic Analysis for Understanding Life Stories
Authors: Weston Sara J. , Cox Keith S. , Condon David M. , Jackson Joshua J.
Published: May 2015

The majority of life narrative research is performed using trained human coders. In contrast, automated linguistic analysis is oft employed in the study of verbal behaviors. These two methodological approaches are directly compared to determine the utility of automated linguistic analysis for the study of life narratives.

In a study of in‐person interviews (N = 158) and a second study of life stories collected online (N = 242), redemption scores are compared to the output of the Linguistic Inquiry and Word Count (Pennebaker, Francis & Booth, 2001). Additionally, patterns of language are found using exploratory principal components analysis.

In both studies, redemption scores are modestly correlated with some LIWC categories and unassociated with the components. Patterns of language do not replicate across samples, indicating that the structure of language does not extend to a broader population. Redemption scores and linguistic components are independent predictors of life satisfaction up to 3 years later.

These studies converge on the finding that human‐coded redemption and automated linguistic analysis are complementary and nonredundant methods of analyzing life narratives, and considerations for the study of life narratives are discussed.
British Icons and Catholic perfidy – Anglo‐Saxon historiography and the battle for Crimean war nursing
Authors: Wells John S G , Bergin Michael
Published: May 2015

Taking as its starting point Carr's view that historical narrative reflects the preoccupations of the time in which it is written and Foucault's concept of consensual historical discourse as the outcome of a social struggle in which the victor suppresses or at least diminishes contrary versions of historical events in favour of their own, this paper traces and discusses the historical narrative of British nursing in the Crimean war and, in particular, three competing narratives that have arisen in the latter half of the 20th century and the first decade of the 21st. These are the established narrative surrounding Florence Nightingale, the new narrative surrounding Mary Seacole and an Irish narrative surrounding the role of the Sisters of Mercy. It is argued that the increased vehemence of the debate surrounding these narratives is representative of the changes that have taken place in British society. However, we also argue that the Irish narrative and its critique are reflective of deep‐rooted Anglo‐Protestant attitudes articulated by Nightingale and uncritically accepted by subsequent historians even in modern British historiography.
The Comparative Burden of Chronic Widespread Pain and Fibromyalgia in the United States
Authors: Schaefer Caroline , Mann Rachael , Masters Elizabeth T. , Cappelleri Joseph C. , Daniel Shoshana R. , Zlateva Gergana , McElroy Heather J. , Chandran Arthi B. , Adams Edgar H. , Assaf Annlouise R. , McNett Michael , Mease Philip , Silverman Stuart , Staud Roland
Published: May 2015

Background/Purpose

Little information exists on the comparative patient and economic burden of chronic widespread pain (CWP) and fibromyalgia (FM) in the United States.

Methods

This multistage, observational study included an online screening survey of a large geographically diverse US sample to assess CWP status, a physician/site visit to determine FM diagnosis, and an online subject questionnaire to capture clinical characteristics, pain, health status, functioning, sleep, healthcare resource use (HRU), productivity, and costs. Based on the screener and physician evaluation, mutually exclusive groups of subjects without CWP (CWP−), with CWP but without FM (CWP+), and with confirmed FM were identified.

Results

Disease burden was examined in 472 subjects (125 CWP‐, 176 CWP+, 171 FM). Age, race, and ethnicity were similar across groups. Mean body mass index and number of comorbidities increased from CWP− to CWP+ to FM (P = 0.0044, P < 0.0001, respectively). From CWP− to CWP+ to FM, there were reductions in health status (EQ‐5D, SF‐12) and sleep outcomes (MOS‐SS, SSQ) (all P < 0.05). Pain severity, interference with function (BPI‐SF), and overall work impairment (WPAI:SHP) increased from CWP− to CWP+ to FM (all P < 0.0001). Higher proportions of CWP+ (52.8%) and FM subjects (62.6%) were taking pain‐related prescription medications relative to CWP− subjects (32.8%; P < 0.0001). Significant differences in total direct and indirect costs across the three groups (both P < 0.0001) were observed, with highest costs among FM subjects.

Conclusion

Fibromyalgia subjects were characterized by the greatest disease burden with more comorbidities and pain‐related medications, poorer health status, function, sleep, lower productivity, and higher costs.
Influence of Centrally Mediated Symptoms on Postoperative Pain in Osteoarthritis Patients Undergoing Total Knee Arthroplasty: A Prospective Observational Evaluation
Authors: Kim Shin Hyung , Yoon Kyung Bong , Yoon Duck Mi , Yoo Ji Hyun , Ahn Ki Ryang
Published: May 2015

Background

Central sensitization plays an important role in the chronic pain experienced by osteoarthritis (OA) patients. In this prospective observational study, we investigated the influence of the level of preoperative centrally mediated symptoms measured by the Central Sensitization Inventory (CSI) on pain intensity after total knee arthroplasty (TKA) for OA.

Methods

Ninety‐eight female OA patients undergoing TKA were enrolled in this study. We assessed CSI scores, pain‐related data, and other clinical data preoperatively. All patients received spinal anesthesia and postoperative epidural analgesia. Pain intensity (at rest and on movement) and rescue meperidine requirements were assessed during postoperative days 1 and 2. Also, pain intensity and patient satisfaction were assessed 1 month and 3 months after surgery. After the completion of all postoperative assessments, we separated the study population into a preoperative CSI score ≥40 and <40 group. We assessed pain‐related data between the 2 groups at each assessment time.

Results

Ninety‐one patients completed the postoperative assessments (a preoperative CSI ≥40 group; n = 44, CSI <40 group; n = 47). Patients with preoperative CSI ≥40 complained of a greater pain intensity (P = 0.001) during postoperative days 1 and 2 and required a higher dose of meperidine rescue (P = 0.003) than those with a preoperative CSI <40. The high CSI score group also showed a less favorable outcome in terms of pain relief on follow‐up at 1 month (P = 0.006) and 3 months (P = 0.002) after surgery. In multivariate analysis, a preoperative CSI score ≥40 was the strongest determinant with 5.091 of the highest odds ratio (95% CI 1.324 to 19.523, P = 0.016) for predicting a persistent pain 3 months after surgery among demographic and pain‐related variables.

Conclusions

OA patients with high levels of comorbid centrally mediated symptoms showed severe pain and increased analgesic requirements after TKA in the early postoperative period. Moreover, these patients seemed to be at higher risk of persistent pain, and a high CSI score was predictive of low patient satisfaction in terms of pain relief after surgery.
Hematological findings in children with brucellosis
Authors: Aypak Adalet , Aypak Cenk , Bayram Yasemin
Published: May 2015

Background

Brucellosis produces a variety of non‐specific hematological abnormalities. The aim of the present study was to evaluate the hematological findings in childhood brucellosis.

Methods

Medical records of children with brucellosis admitted to a tertiary hospital in a 1 year period, were analyzed retrospectively.

Results

Sixty‐nine patients (mean age, 14.5 ± 3.3 years) were diagnosed with brucellosis. The most common hematological finding was thrombocytopenia (n = 11, 15.9%). Thrombocytosis was detected in five patients (7.3%), leukopenia in four (5.8%), anemia in three (4.3%), and bicytopenia in three (4.3%). None of the patients had pancytopenia. Blood culture was positive forBrucellaspp. in 41 patients (59.4%). Among those patients with positive blood culture, six (14.6%) had serum agglutination test titer ≤1/80. Platelet (PLT) count was significantly lower in the bacteremia‐positive group. The OR (95%CI) of bacteremia for PLT cut‐off 200 000/mm3was 0.148 (95%CI: 0.031–0.718) and relative risk was 1.718 (95%CI: 1.244–2.372;P = 0.010).

Conclusions

Brucellosis should be kept in mind in the differential diagnosis of isolated thrombocytopenia in pediatric patients from endemic areas.
Conscientiousness and (un)healthy eating: The role of impulsive eating and age in the consumption of daily main meals
Authors: Olsen Svein Ottar , Tuu Ho Huy , Honkanen Pirjo , Verplanken Bas
Published: May 2015

The present study aims to explore the relationship between conscientiousness and the consumption of healthy versus unhealthy main meals. Impulsive eating was tested as a mediator in this relationship, as well as direct effects of age on those constructs. A nationwide representative sample of 1,006 Norwegian adults (18–70 years) within a prospective design was used to test a theoretical model. The structural equation model (SEM), in combination with bootstrapping procedures in AMOS, was the principal analytical method. Conscientiousness was negatively associated with unhealthy and impulsive eating. Impulsive eating was a partial mediator between conscientiousness and unhealthy eating and a full mediator between conscientiousness and healthy eating. Age was positively correlated with conscientiousness and this relationship had an inverted U‐shape form. Finally, age was negatively associated with unhealthy and impulsive eating, and positively associated with healthy eating. This study confirmed the relevance of conscientiousness for healthy, unhealthy, and impulsive eating.
Development and psychometric evaluation of the Interactive Test of Interpersonal Behavior (ITIB): a pilot study examining interpersonal deficits in chronic depression
Authors: Klein Jan Philipp , Kensche Maria , Becker‐Hingst Nadine , Stahl Jörg , Späth Christina , Mentler Tilo , Stoislow Mathias , Herczeg Michael , Hüppe Michael , Schweiger Ulrich
Published: May 2015

Chronic depression is assumed to be caused and maintained by interpersonal deficits. We describe the development and psychometric evaluation of the Interactive Test of Interpersonal Behavior (ITIB) that we developed for self‐assessment of these deficits. Participants with chronic depression (CD, N = 15), episodic depression (ED, N = 15) and healthy controls (HC, N = 15) participated in this pilot study. They completed the ITIB and a number of pen and paper questionnaires including the Lübeck Questionnaire of Preoperational Thinking (LQPT) and the inventory of interpersonal problems (IIP). The ITIB was highly acceptable for use in these participants. Internal consistency for the ITIB was adequate for group comparisons (Cronbach's alpha = 0.649). Item‐total correlations indicated adequate discriminatory power of five of the six items. The ITIB correlated moderately with the LQPT (r = 0.524) and the IIP (r = –0.568). The ITIB score differed significantly between the diagnostic groups (ANOVA F(2,42) = 6.22, p = 0.004). It was the only measure that – albeit at a trend level – was associated with diagnostic group (CD vs. ED) on multinomial logistic regression analysis (B = 0.049 ± 0.029; OR 1.051; p = 0.088). We found preliminary evidence that the ITIB is an acceptable and psychometrically adequate measure of interpersonal behavior that distinguishes between patients with CD and patients with ED. If replicated with an improved version of the test, our results could support the hypothesis that having interpersonal problems is a core deficit in patients with CD.
A Minority Stress Model for Suicidal Ideation in Gay Men
Authors: Michaels Matthew S. , Parent Mike C. , Torrey Carrie L.
Published: May 2015

There is a dearth of research on mechanisms underlying higher rates of suicidal ideation among gay men compared to heterosexual men. The purpose of this study was to establish the link between social/psychological predictor variables and suicidal ideation by testing a hypothesized minority stress model. Structural equation modeling was used to assess the relationships posited in the model using data from a community sample of 167 gay men. Model fit was adequate and hypothesized relationships were partially supported. Also, depressive symptoms partially mediated the relationship between (less) outness predicting suicidal ideation. These findings imply that therapeutic approaches targeting the coming out process may be more effective than approaches targeting internalized homophobia when suicidal ideation is indicated in the clinical presentation of gay and bisexual men.
Superposition of burial and hydrothermal events: post‐Variscan thermal evolution of the Erzgebirge, Germany
Authors: Wolff Reinhard , Dunkl István , Lange Jan‐Michael , Tonk Christian , Voigt Thomas , von Eynatten Hilmar
Published: May 2015

The post‐Variscan thermal history of the Erzgebirge (Germany) is the result of periods of sedimentary burial, exhumation and superimposed hydrothermal activity. The timing and degree of thermal overprint have been analysed by zircon and apatite (U–Th)/He and apatite fission track thermochronology. The present‐day surface of the Erzgebirge was exhumed to a near‐surface position after the Variscan orogeny. Thermal modelling reveals Permo‐Mesozoic burial to temperatures of up to 80–100 °C, although the sedimentary cover thins out towards the north resulting in maximum burial temperatures of less than 40 °C. This thermal pattern was locally modified by Cretaceous hydrothermal activity that reset the zircon (U–Th)/He thermochronometer along ore veins. The thermal models show no significant regional exhumation during Cenozoic times, indicating that the peneplain‐like morphology of the basement is a Late Cretaceous feature.
Combretastatin A4‐phosphate and its potential in veterinary oncology: a review
Authors: Abma E. , Daminet S. , Smets P. , Ni Y. , de Rooster H.
Published: May 2015

For many years, research on anticancer therapy has focussed almost exclusively on targeting cancer cells directly, to selectively kill them or restrict their growth. But limited advances in this strategy have led researchers to shift their attention to other potential targets. Active research is now on‐going on targeting tumour stroma. Vascular disrupting agents (VDAs) appear a promising class of anticancer drugs that are currently under investigation as a sole or combined therapy in human cancer patients. This article will briefly touch on the history and biology of combretastatin A4‐phosphate (CA4P) as a typical example of VDAs and will concentrate on the side effects that can be expected when used in veterinary patients. Particularly, the pathogenesis of these side effects and how they may be prevented and/or treated will be discussed. The purpose of this article is to illustrate the potentials of CA4P as anticancer therapy in veterinary oncology patients.
Evaluation of electropolished stainless steel electrodes for use in DC high voltage photoelectron guns
Authors: BastaniNejad Mahzad , Elmustafa Abdelmageed A. , Forman Eric , Covert Steven , Hansknecht John , Hernandez-Garcia Carlos , Poelker Matthew , Das Lopa , Kelley Michael , Williams Phillip
Published: May 2015

DC high voltage photoelectron guns are used to produce polarized electron beams for accelerator-based nuclear and high-energy physics research. Low-level field emission (∼nA) from the cathode electrode degrades the vacuum within the photogun and reduces the photoelectron yield of the delicate GaAs-based photocathode used to produce the electron beams. High-level field emission (>μA) can cause significant damage the photogun. To minimize field emission, stainless steel electrodes are typically diamond-paste polished, a labor-intensive process often yielding field emission performance with a high degree of variability, sample to sample. As an alternative approach and as comparative study, the performance of electrodes electropolished by conventional commercially available methods is presented. Our observations indicate the electropolished electrodes exhibited less field emission upon the initial application of high voltage, but showed less improvement with gas conditioning compared to the diamond-paste polished electrodes. In contrast, the diamond-paste polished electrodes responded favorably to gas conditioning, and ultimately reached higher voltages and field strengths without field emission, compared to electrodes that were only electropolished. The best performing electrode was one that was both diamond-paste polished and electropolished, reaching a field strength of 18.7 MV/m while generating less than 100 pA of field emission. The authors speculate that the combined processes were the most effective at reducing both large and small scale topography. However, surface science evaluation indicates topography cannot be the only relevant parameter when it comes to predicting field emission performance.
Morphogenesis and mechanostabilization of complex natural and 3D printed shapes
Authors: Tiwary Chandra Sekhar , Kishore Sharan , Sarkar Suman , Mahapatra Debiprosad Roy , Ajayan Pulickel M. , Chattopadhyay Kamanio
Published: May 2015

3D printing demonstrates causality between natural shape selection as evolutionary outcome and the mechanostabilization of seashells.
Twentieth century turnover of Mexican endemic avifaunas: Landscape change versus climate drivers
Authors: Peterson A. Townsend , Navarro-Sigüenza Adolfo G. , Martínez-Meyer Enrique , Cuervo-Robayo Angela P. , Berlanga Humberto , Soberón Jorge
Published: May 2015

Evaluation of various climate change factors on Mexican bird populations shows temperature has the strongest influence.
Strontium isotopes delineate fine-scale natal origins and migration histories of Pacific salmon
Authors: Brennan Sean R. , Zimmerman Christian E. , Fernandez Diego P. , Cerling Thure E. , McPhee Megan V. , Wooller Matthew J.
Published: May 2015

Strontium isotopes simultaneously delineate fine-scale natal habitats and migrations of Pacific salmon harvested during a coastal commercial fishery.
Reaerosolization of Spores from Flooring Surfaces To Assess the Risk of Dissemination and Transmission of Infections
Authors: Paton Susan , Thompson Katy-Anne , Parks Simon R. , Bennett Allan M.
Published: May 2015

The aim of this study was to quantify reaerosolization of microorganisms caused by walking on contaminated flooring to assess the risk to individuals accessing areas contaminated with pathogenic organisms, for example, spores of
Bacillus anthracis
. Industrial carpet and polyvinyl chloride (PVC) floor coverings were contaminated with aerosolized spores of
Bacillus atrophaeus
by using an artist airbrush to produce deposition of ∼10
3
to 10
4
CFU · cm
−2
. Microbiological air samplers were used to quantify the particle size distribution of the aerosol generated when a person walked over the floorings in an environmental chamber. Results were expressed as reaerosolization factors (percent per square centimeter per liter), to represent the ratio of air concentration to surface concentration generated. Walking on carpet generated a statistically significantly higher reaerosolization factor value than did walking on PVC (
t
= 20.42;
P
< 0.001). Heavier walking produced a statistically significantly higher reaerosolization factor value than did lighter walking (
t
= 12.421;
P
< 0.001). Height also had a statistically significant effect on the reaerosolization factor, with higher rates of recovery of
B. atrophaeus
at lower levels, demonstrating a height-dependent gradient of particle reaerosolization. Particles in the respirable size range were recovered in all sampling scenarios (mass mean diameters ranged from 2.6 to 4.1 μm). The results of this study can be used to produce a risk assessment of the potential aerosol exposure of a person accessing areas with contaminated flooring in order to inform the choice of appropriate respiratory protective equipment and may aid in the selection of the most suitable flooring types for use in health care environments, to reduce aerosol transmission in the event of contamination.
Involvement of Colonizing Bacillus Isolates in Glucovanillin Hydrolysis during the Curing of Vanilla planifolia Andrews
Authors: Chen Yonggan , Gu Fenglin , Li Jihua , He Shuzhen , Xu Fei , Fang Yiming
Published: May 2015

Vanilla beans were analyzed using biochemical methods, which revealed that glucovanillin disperses from the inner part to the outer part of the vanilla bean during the curing process and is simultaneously hydrolyzed by β-
d
-glucosidase. Enzymatic hydrolysis was found to occur on the surface of the vanilla beans. Transcripts of the β-
d
-glucosidase gene (
bgl
) of colonizing microorganisms were detected. The results directly indicate that colonizing microorganisms are involved in glucovanillin hydrolysis. Phylogenetic analysis based on 16S rRNA gene sequences showed that the colonizing microorganisms mainly belonged to the
Bacillus
genus.
bgl
was detected in all the isolates and presented clustering similar to that of the isolate taxonomy. Furthermore, inoculation of green fluorescent protein-tagged isolates showed that the
Bacillus
isolates can colonize vanilla beans. Glucovanillin was metabolized as the sole source of carbon in a culture of the isolates within 24 h. These isolates presented unique glucovanillin degradation capabilities. Vanillin was the major volatile compound in the culture. Other compounds, such as α-cubebene, β-pinene, and guaiacol, were detected in some isolate cultures. Colonizing
Bacillus
isolates were found to hydrolyze glucovanillin in culture, indirectly demonstrating the involvement of colonizing
Bacillus
isolates in glucovanillin hydrolysis during the vanilla curing process. Based on these results, we conclude that colonizing
Bacillus
isolates produce β-
d
-glucosidase, which mediates glucovanillin hydrolysis and influences flavor formation.
Wastewater Analysis Indicates that Genetically Diverse Astroviruses, Including Strains Belonging to Novel Clades MLB and VA, Are Circulating within Japanese Populations
Authors: Hata Akihiko , Katayama Hiroyuki , Kitajima Masaaki , Furumai Hiroaki
Published: May 2015

Human astroviruses (HAstVs) are a common etiological agent of infantile gastroenteritis. Recent studies revealed that novel astrovirus (AstV) strains of the MLB clade (MLB-AstVs) and VA clade (VA-AstVs), which are genetically distinct from the classic HAstVs, are circulating in the human population. In the present study, we quantified classic HAstVs as well as carried out a genetic analysis of classic and novel HAstVs in wastewater in Japan. The concentration of classic HAstVs in the influent water samples ranged from 104to 105copies per liter, and the amount removed by wastewater treatment was determined to be 2.4 ± 0.3 log10. Four types of classic HAstV strains (HAstV types 1, 2, 5, and 4/8) as well as novel AstV strains belonging to the MLB-2, VA-1, and VA-2 clades were identified using reverse transcription-PCR (RT-PCR) assays, including assays newly developed for the detection of strains of the MLB and VA clades, followed by cloning and nucleotide sequencing. Our results suggest that genetically diverse AstV strains are circulating among the human population in Japan. The newly developed (semi)nested RT-PCR assays for these novel AstV clades are useful to identify and characterize the novel AstVs in environmental waters.
Chromosome-Directed PCR-Based Detection and Quantification of Bacillus cereus Group Members with Focus on B. thuringiensis Serovar israelensis Active against Nematoceran Larvae
Authors: Schneider Salome , Hendriksen Niels B. , Melin Petter , Lundström Jan O. , Sundh Ingvar
Published: May 2015

Bacillus thuringiensis
serovar israelensis is a wide-spread soil bacterium affiliated with the
B. cereus
group (Bcg) and is widely used in biocontrol products applied against mosquito and black fly larvae. For monitoring and quantification of applied
B. thuringiensis
serovar israelensis and its effect on indigenous
B. thuringiensis
serovar israelensis and Bcg assemblages, efficient and reliable tools are essential. The abundance and properties of
B. thuringiensis
serovar israelensis strains in the environment traditionally have been investigated with cultivation-dependent techniques, which are hampered by low sensitivity and the morphological similarity between
B. cereus
and
B. thuringiensis
. Currently available PCR-based detection and quantification tools target markers located on plasmids. In this study, a new cultivation-independent PCR-based method for efficient and specific quantification of
B. thuringiensis
serovar israelensis and Bcg is presented, utilizing two sets of PCR primers targeting the bacterial chromosome. Sequence database searches and empirical tests performed on target and nontarget species, as well as on bulk soil DNA samples, demonstrated that this diagnostic tool is specific for
B. thuringiensis
serovar israelensis and Bcg. The method will be useful for comparisons of Bcg and
B. thuringiensis
serovar israelensis abundances in the same samples. Moreover, the effect of
B. thuringiensis
serovar israelensis-based insecticide application on the total Bcg assemblages, including indigenous populations, can be investigated. This type of information is valuable in risk assessment and policy making for use of
B. thuringiensis
serovar israelensis in the environment.
Microbiota at Multiple Body Sites during Pregnancy in a Rural Tanzanian Population and Effects of Moringa-Supplemented Probiotic Yogurt
Authors: Bisanz Jordan E. , Enos Megan K. , PrayGod George , Seney Shannon , Macklaim Jean M. , Chilton Stephanie , Willner Dana , Knight Rob , Fusch Christoph , Fusch Gerhard , Gloor Gregory B. , Burton Jeremy P. , Reid Gregor
Published: May 2015

The nutritional status of pregnant women is vital for healthy outcomes and is a concern for a large proportion of the world's population. The role of the microbiota in pregnancy and nutrition is a promising new area of study with potential health ramifications. In many African countries, maternal and infant death and morbidity are associated with malnutrition. Here, we assess the influence of probiotic yogurt containing
Lactobacillus rhamnosus
GR-1, supplemented with Moringa plant as a source of micronutrients, on the health and oral, gut, vaginal, and milk microbiotas of 56 pregnant women in Tanzania. In an open-label study design, 26 subjects received yogurt daily, and 30 were untreated during the last two trimesters and for 1 month after birth. Samples were analyzed using 16S rRNA gene sequencing, and dietary recalls were recorded. Women initially categorized as nourished or undernourished consumed similar calories and macronutrients, which may explain why there was no difference in the microbiota at any body site. Consumption of yogurt increased the relative abundance of
Bifidobacterium
and decreased
Enterobacteriaceae
in the newborn feces but had no effect on the mother's microbiota at any body site. The microbiota of the oral cavity and GI tract remained stable over pregnancy, but the vaginal microbiota showed a significant increase in diversity leading up to and after birth. In summary, daily micronutrient-supplemented probiotic yogurt provides a safe, affordable food for pregnant women in rural Tanzania, and the resultant improvement in the gut microbial profile of infants is worthy of further study.
Comparative Analysis of Denitrifying Activities of Hyphomicrobium nitrativorans, Hyphomicrobium denitrificans, and Hyphomicrobium zavarzinii
Authors: Martineau Christine , Mauffrey Florian , Villemur Richard
Published: May 2015

Hyphomicrobium
spp. are commonly identified as major players in denitrification systems supplied with methanol as a carbon source. However, denitrifying
Hyphomicrobium
species are poorly characterized, and very few studies have provided information on the genetic and physiological aspects of denitrification in pure cultures of these bacteria. This is a comparative study of three denitrifying
Hyphomicrobium
species,
H. denitrificans
ATCC 51888,
H. zavarzinii
ZV622, and a newly described species,
H. nitrativorans
NL23, which was isolated from a denitrification system treating seawater. Whole-genome sequence analyses revealed that although they share numerous orthologous genes, these three species differ greatly in their nitrate reductases, with gene clusters encoding a periplasmic nitrate reductase (Nap) in
H. nitrativorans
, a membrane-bound nitrate reductase (Nar) in
H. denitrificans
, and one Nap and two Nar enzymes in
H. zavarzinii
. Concurrently with these differences observed at the genetic level, important differences in the denitrification capacities of these
Hyphomicrobium
species were determined.
H. nitrativorans
grew and denitrified at higher nitrate and NaCl concentrations than did the two other species, without significant nitrite accumulation. Significant increases in the relative gene expression levels of the nitrate (
napA
) and nitrite (
nirK
) reductase genes were also noted for
H. nitrativorans
at higher nitrate and NaCl concentrations. Oxygen was also found to be a strong regulator of denitrification gene expression in both
H. nitrativorans
and
H. zavarzinii
, although individual genes responded differently in these two species. Taken together, the results presented in this study highlight the potential of
H. nitrativorans
as an efficient and adaptable bacterium that is able to perform complete denitrification under various conditions.
Molybdenum Availability Is Key to Nitrate Removal in Contaminated Groundwater Environments
Authors: Thorgersen Michael P. , Lancaster W. Andrew , Vaccaro Brian J. , Poole Farris L. , Rocha Andrea M. , Mehlhorn Tonia , Pettenato Angelica , Ray Jayashree , Waters R. Jordan , Melnyk Ryan A. , Chakraborty Romy , Hazen Terry C. , Deutschbauer Adam M. , Arkin Adam P. , Adams Michael W. W.
Published: May 2015

The concentrations of molybdenum (Mo) and 25 other metals were measured in groundwater samples from 80 wells on the Oak Ridge Reservation (ORR) (Oak Ridge, TN), many of which are contaminated with nitrate, as well as uranium and various other metals. The concentrations of nitrate and uranium were in the ranges of 0.1 μM to 230 mM and <0.2 nM to 580 μM, respectively. Almost all metals examined had significantly greater median concentrations in a subset of wells that were highly contaminated with uranium (≥126 nM). They included cadmium, manganese, and cobalt, which were 1,300- to 2,700-fold higher. A notable exception, however, was Mo, which had a lower median concentration in the uranium-contaminated wells. This is significant, because Mo is essential in the dissimilatory nitrate reduction branch of the global nitrogen cycle. It is required at the catalytic site of nitrate reductase, the enzyme that reduces nitrate to nitrite. Moreover, more than 85% of the groundwater samples contained less than 10 nM Mo, whereas concentrations of 10 to 100 nM Mo were required for efficient growth by nitrate reduction for two
Pseudomonas
strains isolated from ORR wells and by a model denitrifier,
Pseudomonas stutzeri
RCH2. Higher concentrations of Mo tended to inhibit the growth of these strains due to the accumulation of toxic concentrations of nitrite, and this effect was exacerbated at high nitrate concentrations. The relevance of these results to a Mo-based nitrate removal strategy and the potential community-driving role that Mo plays in contaminated environments are discussed.
Diversity of the Sediment Microbial Community in the Aha Watershed (Southwest China) in Response to Acid Mine Drainage Pollution Gradients
Authors: Sun Weimin , Xiao Tangfu , Sun Min , Dong Yiran , Ning Zengping , Xiao Enzong , Tang Song , Li Jiwei
Published: May 2015

Located in southwest China, the Aha watershed is continually contaminated by acid mine drainage (AMD) produced from upstream abandoned coal mines. The watershed is fed by creeks with elevated concentrations of aqueous Fe (total Fe > 1 g/liter) and SO
4
2−
(>6 g/liter). AMD contamination gradually decreases throughout downstream rivers and reservoirs, creating an AMD pollution gradient which has led to a suite of biogeochemical processes along the watershed. In this study, sediment samples were collected along the AMD pollution sites for geochemical and microbial community analyses. High-throughput sequencing found various bacteria associated with microbial Fe and S cycling within the watershed and AMD-impacted creek. A large proportion of Fe- and S-metabolizing bacteria were detected in this watershed. The dominant Fe- and S-metabolizing bacteria were identified as microorganisms belonging to the genera
Metallibacterium
,
Aciditerrimonas
,
Halomonas
,
Shewanella
,
Ferrovum
,
Alicyclobacillus
, and
Syntrophobacter
. Among them,
Halomonas
,
Aciditerrimonas
,
Metallibacterium
, and
Shewanella
have previously only rarely been detected in AMD-contaminated environments. In addition, the microbial community structures changed along the watershed with different magnitudes of AMD pollution. Moreover, the canonical correspondence analysis suggested that temperature, pH, total Fe, sulfate, and redox potentials (E
h
) were significant factors that structured the microbial community compositions along the Aha watershed.
Identification of GH15 Family Thermophilic Archaeal Trehalases That Function within a Narrow Acidic-pH Range
Authors: Sakaguchi Masayoshi , Shimodaira Satoru , Ishida Shin-nosuke , Amemiya Miko , Honda Shotaro , Sugahara Yasusato , Oyama Fumitaka , Kawakita Masao
Published: May 2015

Two glucoamylase-like genes,
TVN1315
and
Ta0286
, from the archaea
Thermoplasma volcanium
and
T. acidophilum
, respectively, were expressed in
Escherichia coli
. The gene products, TVN1315 and Ta0286, were identified as archaeal trehalases. These trehalases belong to the CAZy database family GH15, although they have putative (α/α)
6
barrel catalytic domain structures similar to those of GH37 and GH65 family trehalases from other organisms. These newly identified trehalases function within a narrow range of acidic pH values (pH 3.2 to 4.0) and at high temperatures (50 to 60°C), and these enzymes display

K
m

values for trehalose higher than those observed for typical trehalases. These enzymes were inhibited by validamycin A; however, the inhibition constants (

K
i

) were higher than those of other trehalases. Three TVN1315 mutants, corresponding to E408Q, E571Q, and E408Q/E571Q mutations, showed reduced activity, suggesting that these two glutamic acid residues are involved in trehalase catalysis in a manner similar to that of glucoamylase. To date, TVN1315 and Ta0286 are the first archaeal trehalases to be identified, and this is the first report of the heterologous expression of GH15 family trehalases. The identification of these trehalases could extend our understanding of the relationships between the structure and function of GH15 family enzymes as well as glycoside hydrolase family enzymes; additionally, these enzymes provide insight into archaeal trehalose metabolism.
A Versatile Family 3 Glycoside Hydrolase from Bifidobacterium adolescentis Hydrolyzes β-Glucosides of the Fusarium Mycotoxins Deoxynivalenol, Nivalenol, and HT-2 Toxin in Cereal Matrices
Authors: Michlmayr Herbert , Varga Elisabeth , Malachova Alexandra , Nguyen Nhung Thi , Lorenz Cindy , Haltrich Dietmar , Berthiller Franz , Adam Gerhard
Published: May 2015

Glycosylation plays a central role in plant defense against xenobiotics, including mycotoxins. Glucoconjugates of
Fusarium
toxins, such as deoxynivalenol-3-
O
-β-
d
-glucoside (DON-3G), often cooccur with their parental toxins in cereal-based food and feed. To date, only limited information exists on the occurrence of glucosylated mycotoxins and their toxicological relevance. Due to a lack of analytical standards and the requirement of high-end analytical instrumentation for their direct determination, hydrolytic cleavage of β-glucosides followed by analysis of the released parental toxins has been proposed as an indirect determination approach. This study compares the abilities of several fungal and recombinant bacterial β-glucosidases to hydrolyze the model analyte DON-3G. Furthermore, substrate specificities of two fungal and two bacterial (
Lactobacillus brevis
and
Bifidobacterium adolescentis
) glycoside hydrolase family 3 β-glucosidases were evaluated on a broader range of substrates. The purified recombinant enzyme from
B. adolescentis
(
Ba
Bgl) displayed high flexibility in substrate specificity and exerted the highest hydrolytic activity toward 3-
O
-β-
d
-glucosides of the trichothecenes deoxynivalenol (DON), nivalenol, and HT-2 toxin. A

K
m

of 5.4 mM and a
V
max
of 16 μmol min
−1
mg
−1
were determined with DON-3G. Due to low product inhibition (DON and glucose) and sufficient activity in several extracts of cereal matrices, this enzyme has the potential to be used for indirect analyses of trichothecene-β-glucosides in cereal samples.