bluuebunny/crossref_metadata_2025_split huggingface dataset:
A pragmatic comparison of noise burst and electric shock unconditioned stimuli for fear conditioning research with many trials
Authors: Sperl Matthias F. J. , Panitz Christian , Hermann Christiane , Mueller Erik M. 
Published: June 2016

AbstractSeveral methods that are promising for studying the neurophysiology of fear conditioning (e.g., EEG, MEG) require a high number of trials to achieve an adequate signal‐to‐noise ratio. While electric shock and white noise burst are among the most commonly used unconditioned stimuli (US) in conventional fear conditioning studies with few trials, it is unknown whether these stimuli are equally well suited for paradigms with many trials. Here, N = 32 participants underwent a 260‐trial differential fear conditioning and extinction paradigm with a 240‐trial recall test 24 h later and neutral faces as conditioned stimuli. In a between‐subjects design, either white noise bursts (n = 16) or electric shocks (n = 16) served as US, and intensities were determined using the most common procedure for each US (i.e., a fixed 95 dB noise burst and a work‐up procedure for electric shocks, respectively). In addition to differing US types, groups also differed in closely linked US‐associated characteristics (e.g., calibration methods, stimulus intensities, timing). Subjective ratings (arousal/valence), skin conductance, and evoked heart period changes (i.e., fear bradycardia) indicated more reliable, extinction‐resistant, and stable conditioning in the white noise burst versus electric shock group. In fear conditioning experiments where many trials are presented, white noise burst should serve as US.
Sweat pore reactivity as a surrogate measure of sympathetic nervous system activity in trauma‐exposed individuals with and without posttraumatic stress disorder
Authors: Familoni Babajide O. , Gregor Kristin L. , Dodson Thomas S. , Krzywicki Alan T. , Lowery Bobby N. , Orr Scott P. , Suvak Michael K. , Rasmusson Ann M. 
Published: June 2016

AbstractStress analysis by FLIR (forward‐looking infrared) evaluation (SAFE) has been demonstrated to monitor sweat pore activation (SPA) as a novel surrogate measure of sympathetic nervous system (SNS) activity in a normal population. SNS responses to a series of 15 1‐s, 82 dB, white noise bursts were measured by skin conductance (SC) and SAFE monitoring of SPA on the fingers (FiP) and face (FaP) in 10 participants with posttraumatic stress disorder (PTSD) and 16 trauma‐exposed participants without PTSD (Mage = 48.92 ± 12.00 years; 26.9% female). Within participants, SC and FiP responses across trials were strongly correlated (r = .92, p < .001). Correlations between SC and FaP (r = .76, p = .001) and between FiP and FaP (r = .47, p = .005) were smaller. The habituation of SNS responses across the 15 trials was substantial (SC: d = −2.97; FiP: d = −2.34; FaP: d = −1.02). There was a strong correlation between habituation effects for SC and FiP (r = .76, p < .001), but not for SC and FaP (r = .15, p = .45) or FiP and FaP (r = .29, p = .16). Participants with PTSD showed larger SNS responses to the first loud noise than those without PTSD. PTSD reexperiencing symptoms assessed by the PTSD Checklist on the day of testing were associated with the SNS responses to the first loud noise measured by SC (d = 1.19) and FiP (d = .99), but not FaP (d = .10). This study confirms convergence of SAFE and SC as valid measures of SNS activity. SAFE FiP and SC responses were highly predictive of self‐rated PTSD reexperiencing symptoms. SAFE may offer an attractive alternative for applications in PTSD and similar populations.
Detection and isolation of Toxoplasma gondii from fresh semen of naturally infected dogs in Southern Brazil
Authors: Koch MO , Weiss RR , Cruz AA , Soccol VT , Gonçalves KA , Bertol MAF , Beltrame OC , Dittrich RL 
Published: June 2016

ContentsThe aim of this study was to isolate Toxoplasma gondii and determine the viability of the parasite in fresh semen samples of clinically healthy adult dogs naturally infected. Eleven seropositive dogs with T. gondii IgG antibodies from southern Brazil were selected to confirm the presence and viability of T. gondii in fresh semen samples using in vitro isolation in Vero cell culture, polymerase chain reaction (PCR) and sequencing analysis. The presence of viable T. gondii was confirmed by in vitro isolation and PCR in five semen samples. The ITS1 region of the isolated protozoa (TG S4) was amplified and sequenced. The nucleotide sequence obtained was 99% compatible with the T. gondii DNA sequences stored in the GenBank. It has been shown that T. gondii tachyzoites may be isolated in vitro from fresh semen samples of clinically healthy dogs seropositive for T. gondii.
FUSCA3 activates triacylglycerol accumulation in Arabidopsis seedlings and tobacco BY2 cells
Authors: Zhang Meng , Cao Xia , Jia Qingli , Ohlrogge John 
Published: June 2016

SummaryTriacylglycerol (TAG) is the main storage lipid in plant seeds and the major form of plant oil used for food and, increasingly, for industrial and biofuel applications. Several transcription factors, including FUSCA3 (At3 g26790, FUS3), are associated with embryo maturation and oil biosynthesis in seeds. However, the ability of FUS3 to increase TAG biosynthesis in other tissues has not been quantitatively examined. Here, we evaluated the ability of FUS3 to activate TAG accumulation in non‐seed tissues. Overexpression of FUS3 driven by an estradiol‐inducible promoter increased oil contents in Arabidopsis seedlings up to 6% of dry weight; more than 50‐fold over controls. Eicosenoic acid, a characteristic fatty acid of Arabidopsis seed oil, accumulated to over 20% of fatty acids in cotyledons and leaves. These large increases depended on added sucrose, although without sucrose TAG increased three‐ to four‐fold. Inducing the expression of FUS3 in tobacco BY2 cells also increased TAG accumulation, and co‐expression of FUS3 and diacylglycerol acyltransferase 1 (DGAT1) further increased TAG levels to 4% of dry weight. BY2 cell growth was not altered by FUS3 expression, although Arabidopsis seedling development was impaired, consistent with the ability of FUS3 to induce embryo characteristics in non‐seed tissues. Microarrays of Arabidopsis seedlings revealed that FUS3 overexpression increased the expression of a higher proportion of genes involved in TAG biosynthesis than genes involved in fatty acid biosynthesis or other lipid pathways. Together these results provide additional insights into FUS3 functions in TAG metabolism and suggest complementary strategies for engineering vegetative oil accumulation.
Differential Regulation of the Two Ferrochelatase Paralogues in Shewanella loihica PV-4 in Response to Environmental Stresses
Authors: Qiu Dongru , Xie Ming , Dai Jingcheng , An Weixing , Wei Hehong , Tian Chunyuan , Kempher Megan L. , Zhou Aifen , He Zhili , Gu Baohua , Zhou Jizhong 
Published: June 2016

ABSTRACT

Determining the function and regulation of paralogues is important in understanding microbial functional genomics and environmental adaptation. Heme homeostasis is crucial for the survival of environmental microorganisms. Most
Shewanella
species encode two paralogues of ferrochelatase, the terminal enzyme in the heme biosynthesis pathway. The function and transcriptional regulation of two ferrochelatase genes,
hemH1
and
hemH2
, were investigated in
Shewanella
loihica
PV-4. The disruption of
hemH1
but not
hemH2
resulted in a significant accumulation of extracellular protoporphyrin IX (PPIX), the precursor to heme, and decreased intracellular heme levels.
hemH1
was constitutively expressed, and the expression of
hemH2
increased when
hemH1
was disrupted. The transcription of
hemH1
was regulated by the housekeeping sigma factor RpoD and potentially regulated by OxyR, while
hemH2
appeared to be regulated by the oxidative stress-associated sigma factor RpoE2. When an oxidative stress condition was mimicked by adding H
2
O
2
to the medium or exposing the culture to light, PPIX accumulation was suppressed in the Δ
hemH1
mutant. Consistently, transcriptome analysis indicated enhanced iron uptake and suppressed heme synthesis in the Δ
hemH1
mutant. These data indicate that the two paralogues are functional in the heme synthesis pathway but regulated by environmental conditions, providing insights into the understanding of bacterial response to environmental stresses and a great potential to commercially produce porphyrin compounds.

IMPORTANCE
Shewanella
is capable of utilizing a variety of electron acceptors for anaerobic respiration because of the existence of multiple
c
-type cytochromes in which heme is an essential component. The cytochrome-mediated electron transfer across cellular membranes could potentially be used for biotechnological purposes, such as electricity generation in microbial fuel cells and dye decolorization. However, the mechanism underlying the regulation of biosynthesis of heme and cytochromes is poorly understood. Our study has demonstrated that two ferrochelatase genes involved in heme biosynthesis are differentially regulated in response to environmental stresses, including light and reactive oxygen species. This is an excellent example showing how bacteria have evolved to maintain cellular heme homeostasis. More interestingly, the high yields of extracellular protoporphyrin IX by the
Shewanella loihica
PV-4 mutants could be utilized for commercial production of this valuable chemical via bacterial fermentation.
Interaction of Uranium with Bacterial Cell Surfaces: Inferences from Phosphatase-Mediated Uranium Precipitation
Authors: Kulkarni Sayali , Misra Chitra Seetharam , Gupta Alka , Ballal Anand , Apte Shree Kumar 
Published: June 2016

ABSTRACT

Deinococcus radiodurans
and
Escherichia coli
expressing either PhoN, a periplasmic acid phosphatase, or PhoK, an extracellular alkaline phosphatase, were evaluated for uranium (U) bioprecipitation under two specific geochemical conditions (GCs): (i) a carbonate-deficient condition at near-neutral pH (GC1), and (ii) a carbonate-abundant condition at alkaline pH (GC2). Transmission electron microscopy revealed that recombinant cells expressing PhoN/PhoK formed cell-associated uranyl phosphate precipitate under GC1, whereas the same cells displayed extracellular precipitation under GC2. These results implied that the cell-bound or extracellular location of the precipitate was governed by the uranyl species prevalent at that particular GC, rather than the location of phosphatase. MINTEQ modeling predicted the formation of predominantly positively charged uranium hydroxide ions under GC1 and negatively charged uranyl carbonate-hydroxide complexes under GC2. Both microbes adsorbed 6- to 10-fold more U under GC1 than under GC2, suggesting that higher biosorption of U to the bacterial cell surface under GC1 may lead to cell-associated U precipitation. In contrast, at alkaline pH and in the presence of excess carbonate under GC2, poor biosorption of negatively charged uranyl carbonate complexes on the cell surface might have resulted in extracellular precipitation. The toxicity of U observed under GC1 being higher than that under GC2 could also be attributed to the preferential adsorption of U on cell surfaces under GC1. This work provides a vivid description of the interaction of U complexes with bacterial cells. The findings have implications for the toxicity of various U species and for developing biological aqueous effluent waste treatment strategies.

IMPORTANCE
The present study provides illustrative insights into the interaction of uranium (U) complexes with recombinant bacterial cells overexpressing phosphatases. This work demonstrates the effects of aqueous speciation of U on the biosorption of U and the localization pattern of uranyl phosphate precipitated as a result of phosphatase action. Transmission electron microscopy revealed that location of uranyl phosphate (cell associated or extracellular) was primarily influenced by aqueous uranyl species present under the given geochemical conditions. The data would be useful for understanding the toxicity of U under different geochemical conditions. Since cell-associated precipitation of metal facilitates easy downstream processing by simple gravity-based settling down of metal-loaded cells, compared to cumbersome separation techniques, the results from this study are of considerable relevance to effluent treatment using such cells.
Relationship of Bacterial Richness to Organic Degradation Rate and Sediment Age in Subseafloor Sediment
Authors: Walsh Emily A. , Kirkpatrick John B. , Pockalny Robert , Sauvage Justine , Spivack Arthur J. , Murray Richard W. , Sogin Mitchell L. , D'Hondt Steven 
Published: June 2016

ABSTRACT
Subseafloor sediment hosts a large, taxonomically rich, and metabolically diverse microbial ecosystem. However, the factors that control microbial diversity in subseafloor sediment have rarely been explored. Here, we show that bacterial richness varies with organic degradation rate and sediment age. At three open-ocean sites (in the Bering Sea and equatorial Pacific) and one continental margin site (Indian Ocean), richness decreases exponentially with increasing sediment depth. The rate of decrease in richness with increasing depth varies from site to site. The vertical succession of predominant terminal electron acceptors correlates with abundance-weighted community composition but does not drive the vertical decrease in richness. Vertical patterns of richness at the open-ocean sites closely match organic degradation rates; both properties are highest near the seafloor and decline together as sediment depth increases. This relationship suggests that (i) total catabolic activity and/or electron donor diversity exerts a primary influence on bacterial richness in marine sediment and (ii) many bacterial taxa that are poorly adapted for subseafloor sedimentary conditions are degraded in the geologically young sediment, where respiration rates are high. Richness consistently takes a few hundred thousand years to decline from near-seafloor values to much lower values in deep anoxic subseafloor sediment, regardless of sedimentation rate, predominant terminal electron acceptor, or oceanographic context.

IMPORTANCE
Subseafloor sediment provides a wonderful opportunity to investigate the drivers of microbial diversity in communities that may have been isolated for millions of years. Our paper shows the impact of
in situ
conditions on bacterial community structure in subseafloor sediment. Specifically, it shows that bacterial richness in subseafloor sediment declines exponentially with sediment age, and in parallel with organic-fueled oxidation rate. This result suggests that subseafloor diversity ultimately depends on electron donor diversity and/or total community respiration. This work studied how and why biological richness changes over time in the extraordinary ecosystem of subseafloor sediment.
Elution Is a Critical Step for Recovering Human Adenovirus 40 from Tap Water and Surface Water by Cross-Flow Ultrafiltration
Authors: Shi Hang , Xagoraraki Irene , Parent Kristin N. , Bruening Merlin L. , Tarabara Volodymyr V. 
Published: June 2016

ABSTRACT

This paper examines the recovery of the enteric adenovirus human adenovirus 40 (HAdV 40) by cross-flow ultrafiltration and interprets recovery values in terms of physicochemical interactions of virions during sample concentration. Prior to ultrafiltration, membranes were either blocked by exposure to calf serum (CS) or coated with a polyelectrolyte multilayer (PEM). HAdV 40 is a hydrophobic virus with a point of zero charge between pH 4.0 and pH 4.3. In accordance with predictions from the extended Derjaguin-Landau-Verwey-Overbeek theory, the preelution recovery of HAdV (
r
pre
) from deionized water was higher with PEM-coated membranes (
r
pre
PEM
= 74.8% ± 9.7%) than with CS-blocked membranes (
r
pre
CS
= 54.1% ± 6.2%). With either membrane type, the total virion recovery after elution (
r
post
) was high for both deionized water (
r
post
PEM
= 99.5% ± 6.6% and
r
post
CS
= 98.8% ± 7.7%) and tap water (
r
post
PEM
= 89% ± 15% and
r
post
CS
= 93.7% ± 6.9%). The nearly 100% recoveries suggest that the polyanion (sodium polyphosphate) and surfactant (Tween 80) in the eluent disrupt electrostatic and hydrophobic interactions between the virion and the membrane. Addition of EDTA to the eluent greatly improved the elution efficacy (
r
post
CS
= 88.6% ± 4.3% and
r
post
PEM
= 87.0% ± 6.9%) with surface water, even when the organic carbon concentration in the water was high (9.4 ± 0.1 mg/liter). EDTA likely disrupts cation bridging between virions and particles in the feed water matrix or the fouling layer on the membrane surface. For complex water matrices, the eluent composition is the most important factor for achieving high virion recovery.

IMPORTANCE
Herein we present the results of a comprehensive physicochemical characterization of HAdV 40, an important human pathogen. The data on HAdV 40 surface properties enabled rigorous modeling to gain an understanding of the energetics of virion-virion and virion-filter interactions. Cross-flow filtration for concentration and recovery of HAdV 40 was evaluated, with postelution recoveries from ultrapure water (99%), tap water (∼91%), and high-carbon-content surface water (∼84%) being demonstrated. These results are significant because of the very low adenovirus recoveries that have been reported, to date, for other methods. The recovery data were interpreted in terms of specific interactions, and the eluent composition was designed accordingly to maximize HAdV 40 recovery.
Mini-Tn
7
Insertion in an Artificial
att
Tn
7
Site Enables Depletion of the Essential Master Regulator CtrA in the Phytopathogen Agrobacterium tumefaciens
Authors: Figueroa-Cuilan Wanda , Daniel Jeremy J. , Howell Matthew , Sulaiman Aliyah , Brown Pamela J. B. 
Published: June 2016

ABSTRACT

Mechanistic studies of many processes in
Agrobacterium tumefaciens
have been hampered by a lack of genetic tools for characterization of essential genes. In this study, we used a Tn
7
-based method for inducible control of transcription from an engineered site on the chromosome. We demonstrate that this method enables tighter control of inducible promoters than plasmid-based systems and can be used for depletion studies. The method enables the construction of depletion strains to characterize the roles of essential genes in
A. tumefaciens
. Here, we used the strategy to deplete the alphaproteobacterial master regulator CtrA and found that depletion of this essential gene results in dramatic rounding of cells, which become nonviable.

IMPORTANCE
Agrobacterium tumefaciens
is a bacterial plant pathogen and natural genetic engineer. Thus, studies of essential processes, including cell cycle progression, DNA replication and segregation, cell growth, and division, may provide insights for limiting disease or improving biotechnology applications.
Children with chronic health disorders travelling to the tropics: a prospective observational study
Authors: Ducrocq Camille , Sommet Julie , Levy Dora , Trieu Thanh-Van , Quercia Fabrice , Morin Laurence , Belletre Xavier , Koehl Bérengère , Sorge Frederic , Alberti Corinne , de Pontual Loic , Faye Albert 
Published: June 2016

BackgroundThe number of trips to the tropics taken by children with chronic health disorders (CHDs) is increasing.MethodsAll of the children with CHDs who attended two international vaccination centres in France before travelling to the tropics were included in a prospective, exposed/unexposed study. Each child was age-matched with two control children and followed for 1 month after returning from the tropics.ResultsFifty-six children with CHDs and 107 control children were included. The children's median age was 6 years old (IQR 2–11). Of the study participants, 127/163 (78%) travelled to West Africa, mainly to visit relatives. The median duration of the stay was 42 days (IQR 31–55). The age of the children, the destination and the duration of the trip were similar between the two groups. Sickle cell disease (23/56) and asthma (16/56) were the most common CHDs. Overall, the children with CHDs experienced more clinical events than the control patients did (p<0.05); however, there was no difference when chronic disease exacerbations were excluded (p=0.64) or when only the period abroad was considered (p=0.24). One child with a recent genetic diagnosis of atypical haemolytic uraemic syndrome died from a first disease exacerbation.ConclusionsHealth problems among children with CHDs travelling abroad are mainly related to chronic disease exacerbations, which mostly occur after the children return. Patients with diseases that require highly specialised care for an exacerbation should avoid travelling to resource-limited tropical countries.
Interventions for Menière's disease: protocol for an umbrella systematic review and a network meta-analysis
Authors: van Esch Babette F , van der Zaag-Loonen Hester J , Bruintjes Tjasse D , van Benthem Peter Paul G 
Published: June 2016

IntroductionThe large number of treatment modalities for patients diagnosed with Menière's disease (MD) complicates the selection of the best available treatment as the comparative efficacy of these interventions is not clear. We aim to identify the treatment or treatments with the highest efficacy of current pharmacological and non-pharmacological treatments for MD.Methods and analysisWe will identify all available systematic reviews on the treatment of MD. An online database search will be conducted in association with the UK Cochrane Centre, particularly the Ear, Nose and Throat Group. We will screen the systematic reviews for eligible randomised controlled trials (RCTs) to execute a network meta-analysis. In addition, online databases will be checked for eligible RCTs on treatments that were published after the latest systematic search was conducted. The characteristics of each RCT will be summarised, including the general design, the participants, the interventions, the outcome measurements, the duration of therapy and adverse events. The risk of bias will be assessed by means of the Cochrane Collaboration's risk of bias tool. The included studies will be assessed for methodological and statistical heterogeneity; the latter will be quantified by means of the I2statistic. The primary outcome will be the efficacy of treatment in terms of control of vertigo attacks. Secondary outcome measures will be the loss or improvement of hearing, severity of vertigo attacks and tinnitus, perception of aural fullness, quality of life, and the incidence of adverse events and complications.Ethics and disseminationFormal ethical approval is not required as primary data will not be collected. The review will be disseminated in peer-reviewed publications and conference presentations.PROSPERO registration numberCRD42015024243.