bluuebunny/crossref_metadata_2025 huggingface dataset:
Rat orbitofrontal ensemble activity contains a multiplexed but value-invariant representation of task structure in an odor sequence task
Authors: Zhou Jingfeng , Gardner Matthew P.H. , Stalnaker Thomas A. , Ramus Seth J. , Wikenheiser Andrew M. , Niv Yael , Schoenbaum Geoffrey
Published: December 2018

The orbitofrontal cortex (OFC) has long been implicated in signaling information about expected outcomes to facilitate adaptive or flexible behavior. Current proposals focus on signaling of expected reward values versus the representation of a value-agnostic cognitive map of the task. While often suggested as mutually exclusive, these alternatives may represent two extreme ends of a continuum determined by the complexity of the environment and the subjects’ experience in it. As learning proceeds, an initial, detailed cognitive map might be acquired, based largely on external information. With more experience, this hypothesized map can then be tailored to include relevant abstract hidden cognitive constructs. This might default to expected values in situations where other attributes are minimized or largely irrelevant, whereas in richer tasks, a more detailed structure might continue to be represented, at least where relevant to behavior, and possibly alongside value. Here we sought to arbitrate between these options by recording single unit activity from the OFC in rats navigating an odor sequence task analogous to a spatial maze. The odor sequences provided a clearly mappable state space, with 24 unique “positions” defined by sensory information, likelihood of reward, or both. Consistent with the hypothesis that the OFC represents a cognitive map tailored to the subjects’ intentions or plans, we found a close correspondence between how subjects’ behavior suggested they were using the sequences, and the neural representations of the sequences in OFC ensembles. Multiplexed with this value-invariant representation of the task, we also found a representation of the expected value at each location. Thus value and task structure are co-existing and potentially dissociable components of the neural code in OFC.
Mitf links neuronal activity and long-term homeostatic intrinsic plasticity
Authors: Atacho Diahann A. M. , Reynisson Hallur , Pétursdóttir Anna Þóra , Eysteinsson Thor , Steingrímsson Eiríkur , Henry Petersen Pétur
Published: December 2018

Neuroplasticity forms the basis for neuronal circuit complexity and can determine differences between otherwise similar circuits. Although synaptic plasticity is fairly well characterized, much less is known about the molecular mechanisms underlying intrinsic plasticity, especially its transcriptional regulation. We show that the Microphthalmia-associated transcription factor (Mitf), best known as the master regulator of melanocytic cell fate and differentiation, plays a central role in homeostatic intrinsic plasticity of olfactory bulb (OB) projection neurons. Mitral and tufted (M/T) neurons fromMitfmutant mice are hyperexcitable due to reduced Type-A potassium current (IA) and they exhibit reduced expression ofKcnd3, which encodes a potassium voltage-gated channel subunit (Kv4.3) important for generating the IA. Furthermore, expression of theMitfandKcnd3genes is activity-dependent in OB projection neurons, The MITF protein binds to and activates expression fromKcnd3regulatory elements. Activity can therefore affectKcnd3expression directly via MITF. Moreover,Mitfmutant mice have changes in olfactory habituation and have increased habitutation for an odourant following long-term exposure, indicating that regulation ofKcnd3is pivotal for long-term olfactory adaptation. Our findings show thatMitfacts as a direct regulator of intrinsic homeostatic feedback, plays a key role in olfactory adaptation and links neuronal activity, transcriptional changes and neuronal function.

Significance statement

A direct,Mitf-dependent link between neuronal activity and homeostatic changes in the expression of a key potassium channel subunit is demonstrated in projection neurons of the mouse OB. This is one of the first studies that directly link activity and genetically defined changes in intrinsic plasticity, leading to changes in neuronal response. These findings broaden the general understanding of transcriptional regulation of homeostatic intrinsic plasticity in learning and memory. The results are also important for understanding the role ofMitfin other cell types. Regulation of intrinsic plasticity has wide-ranging implications and fundamental importance for neurological diseases such as neurodegeneration, autism and epilepsy.
An increase in spontaneous activity mediates visual habituation
Authors: Miller Jae-eun Kang , Miller Bradley R. , Yuste Rafael
Published: December 2018

The cerebral cortex is spontaneously active, but the function of this ongoing activity remains unclear. One possibility is that spontaneous activity provides contextual information in cortical computations, replaying previously learned patterns of activity that conditions the cortex to respond more efficiently, based on past experience. To test this, we measured the response of neuronal populations in mouse primary visual cortex with chronic two-photon calcium imaging during a visual habituation to a specific oriented stimulus. We unexpectedly found that, during habituation, spontaneous activity increased in neurons across the full range of orientation selectivity, eventually matching that of evoked levels. The increase in spontaneous activity strongly correlated with the degree of habituation. In fact, boosting spontaneous activity with two-photon optogenetic stimulation to the levels of stimulus-evoked activity induced habituation in naive animals. Our study shows that cortical spontaneous activity is causally linked to habituation, which unfolds by minimizing the difference between spontaneous and stimulus-evoked activity levels, rendering the cortex less responsive. We also show how manipulating spontaneous activity can accelerate this type of learning. We hypothesize that spontaneous activity in visual cortex gates incoming sensory information.
Accurate tracking of the mutational landscape of diploid hybrid genomes
Authors: Tattini Lorenzo , Tellini Nicolò , Mozzachiodi Simone , D’Angiolo Melania Jennifer , Loeillet Sophie , Nicolas Alain , Liti Gianni
Published: December 2018

Background

Genome evolution promotes diversity within a population via mutations, recombination, and whole-genome duplication. However, quantifying precisely these factors in diploid hybrid genomes is challenging. Here we present an integrated experimental and computational workflow to accurately track the mutational landscape of yeast diploid hybrids (MuLoYDH) in terms of single-nucleotide variants, small insertions/deletions, copy-number variants and loss-of-heterozygosity.

Results

Haploid Saccharomyces parents were combined into diploid hybrids with fully phased genome and controlled levels of heterozygosity. The resulting hybrids represented the ancestral state and were evolved under different laboratory protocols. Variant simulations enabled to efficiently integrate competitive and standard mapping, depending on local levels of heterozygosity and read length. Experimental validations proved high accuracy and resolution of our computational approach. Finally, applying MuLoYDH to four different diploids revealed striking genetic background effects. Homozygous S. cerevisiae showed ~4-fold higher mutation rate compared to S. paradoxus. In contrast, interspecies hybrids exhibited mutation rates similar to intraspecies hybrids despite 10-fold higher heterozygosity. MuLoYDH unveiled that a substantial fraction of the genome (~200 bp per generation) was shaped by loss-of-heterozygosity and this process was strongly inhibited by high levels of heterozygosity.

Conclusions

We report a comprehensive framework for characterizing the mutational spectrum of yeast diploid hybrids with unprecedented resolution, which can be generalised to other genetic systems. Applying MuLoYDH to laboratory-evolved hybrids provided novel quantitative insights into the evolutionary processes that mould yeast genomes.
Multi-data sensor fusion framework to detect transparent object for the efficient mobile robot mapping
Authors: Singh Ravinder , Nagla Kuldeep Singh
Published: December 2018

Purpose

An efficient perception of the complex environment is the foremost requirement in mobile robotics. At present, the utilization of glass as a glass wall and automated transparent door in the modern building has become a highlight feature for interior decoration, which has resulted in the wrong perception of the environment by various range sensors. The perception generated by multi-data sensor fusion (MDSF) of sonar and laser is fairly consistent to detect glass but is still affected by the issues such as sensor inaccuracies, sensor reliability, scan mismatching due to glass, sensor model, probabilistic approaches for sensor fusion, sensor registration, etc. The paper aims to discuss these issues.

Design/methodology/approach

This paper presents a modified framework – Advanced Laser and Sonar Framework (ALSF) – to fuse the sensory information of a laser scanner and sonar to reduce the uncertainty caused by glass in an environment by selecting the optimal range information corresponding to a selected threshold value. In the proposed approach, the conventional sonar sensor model is also modified to reduce the wrong perception in sonar as an outcome of the diverse range measurement. The laser scan matching algorithm is also modified by taking out the small cluster of laser point (w.r.t. range information) to get efficient perception.

Findings

The probability of the occupied cells w.r.t. the modified sonar sensor model becomes consistent corresponding to diverse sonar range measurement. The scan matching technique is also modified to reduce the uncertainty caused by glass and high computational load for the efficient and fast pose estimation of the laser sensor/mobile robot to generate robust mapping. These stated modifications are linked with the proposed ALSF technique to reduce the uncertainty caused by glass, inconsistent probabilities and high load computation during the generation of occupancy grid mapping with MDSF. Various real-world experiments are performed with the implementation of the proposed approach on a mobile robot fitted with laser and sonar, and the obtained results are qualitatively and quantitatively compared with conventional approaches.

Originality/value

The proposed ASIF approach generates efficient perception of the complex environment contains glass and can be implemented for various robotics applications.
Relative Effects of IFRS Adoption and IFRS Convergence on Financial Statement Comparability
Authors: Lin Steve , Riccardi William N. , Wang Changjiang , Hopkins Patrick E. , Kabureck Gary
Published: December 2018

One of the primary objectives of both adoption of IFRS and convergence between IFRS and U.S. GAAP is to increase financial statement comparability. Using a unique setting in Germany, we compare the effectiveness of these two approaches in achieving this desired outcome. Our empirical tests show that both adoption and convergence lead to an increase in comparability after the new enforcement regulation in 2005. However, difference‐in‐differences tests show that adoption does not lead to a significant incremental increase in comparability beyond convergence. The findings of this study should be of interest to regulators and standard setters as they assess alternative methods of aligning domestic standards with IFRS.
Photoactivated chromophore corneal cross‐linking (PACK‐CXL) for treatment of severe keratitis
Authors: Idrus Elfa Alidrus , Utti Elina Maria , Mattila Jaakko S , Krootila Kari
Published: December 2018

Purpose

To report our experience with photoactivated chromophore corneal cross‐linking (PACK‐CXL) for treating keratitis patients.

Methods

This retrospective study consists of 27 eyes of 26 patients with infectious keratitis treated with PACK‐CXL at the Helsinki University Hospital between 2009 and 2017. Patients were treated with antibiotics/antifungal medications and underwent PACK‐CXL procedure due to lack of clinical response or severe corneal melts. For twenty patients, amniotic membrane transplant (AMT) was done during the same day. Follow‐up after cross‐linking ranged from 1 week to 12 months.

Results

Sixteen infections were related to contact lens wear. Of the 19 eyes showing positive culture, the predominant micro‐organism was Pseudomonas aeruginosa (9 cases). The average re‐epithelization time was 13 days and in 15 cases (56%) the re‐epithelization occurred within one week. In 26 eyes, visual acuity increased and seven patients (26%) had a final visual acuity more or equal to 0.5 (20/40) Snellen.

Conclusions

PACK‐CXL seems to be a safe and potential option for treating patient with infectious keratitis who do not respond to antibiotic therapy.
Survival and functionality of xeno‐free human embryonic stem cell–derived retinal pigment epithelial cells on polyester substrate after transplantation in rabbits
Authors: Ilmarinen Tanja , Thieltges Fabian , Hongisto Heidi , Juuti‐Uusitalo Kati , Koistinen Arto , Kaarniranta Kai , Brinken Ralf , Braun Norbert , Holz Frank G. , Skottman Heli , Stanzel Boris V.
Published: December 2018

Purpose

To study immunogenic properties of human embryonic stem cell–derived retinal pigment epithelium (hESC‐RPE) and to evaluate subretinal xenotransplantation of hESC‐RPE on porous polyethylene terephthalate (PET) in rabbits.

Methods

Human ESC‐RPE cells were characterized by morphology, transepithelial electrical resistance (TER), protein expression and photoreceptor outer segment phagocytosis in vitro. Expression of major histocompatibility complex (MHC) proteins was assessed in conventionally or xeno‐free produced hESC‐RPE ± interferon‐gamma (IFN‐γ) stimulation (n = 1). Xeno‐free hESC‐RPE on PET with TER < 200 Ω·cm2 > or PET alone were transplanted into 18 rabbits with short‐term triamcinolone ± extended tacrolimus immunosuppression. Rabbits were monitored by spectral domain optical coherence tomography. After 4 weeks, the eyes were processed for histology and transmission electron microscopy.

Results

Upon in vitro IFN‐γ stimulation, xeno‐free hESC‐RPE expressed lower level of MHC‐II proteins compared to the conventional cells. Outer nuclear layer (ONL) atrophy was observed over the graft in most cases 4 weeks post‐transplantation. In 3/4 animals with high TER hESC‐RPE, but only in 1/3 animals with low TER hESC‐RPE, ONL atrophy was observed already within 1 week. Retinal cell infiltrations were more frequent in animals with high TER hESC‐RPE. However, the difference was not statistically significant. In three animals, preservation of ONL was observed. Weekly intravitreal tacrolimus did not affect ONL preservation. In all animals, hESC‐RPE cells survived for 4 weeks, but without tacrolimus, enlarged vacuoles accumulated in hESC‐RPE (n = 1).

Conclusions

Xenografted xeno‐free hESC‐RPE monolayers can survive and retain some functionality for 4 weeks following short‐term immunosuppression. The preliminary findings of this study suggest that further investigations to improve transplantation success of hESC‐RPE xenografts in rabbits should be addressed especially toward the roles of hESC‐RPE maturation stage and extended intravitreal immunosuppression.
Detection of visual field defects by opticians – with Damato Multifixation Campimetry Online
Authors: Olsen Ane Sophie , la Cour Morten , Damato Bertil , Kolko Miriam
Published: December 2018

Purpose

To study Damato Multifixation Campimetry Online (DMCO), an inexpensive online visual field test, used for screening at optician shops in Denmark.

Methods

This was an evaluation of a diagnostic test and customers were included if minimum 50 years old, with a visual acuity of minimum 0.5 and with less myopia than 6 D. Standard equipment was a computer, a wireless mouse and a computer monitor. We used the ‘DMCO STANDARD 4,5’ algorithm for screening. DMCO results were electronically transmitted to the authors. Customers with a positive DMCO test received an eye examination including the reference standard Humphrey Visual Field Analyzer 30–2 SITA Fast test. A subset of control participants with a negative DMCO test received the same examination in order to estimate the number of false and true negatives. DMCO specificity and sensitivity were estimated according to five reference standards with 95% confidence intervals.

Results

The population comprised 627 individuals, 381 women and 246 men, from 13 optician shops. Mean age was 62 years (SD 7.4). DMCO was positive in 32 individuals and 27 individuals were classified as ‘true positives’ with diagnoses such as glaucoma, cataract and neurological visual field defects. Of the 595 individuals with a negative DMCO test, 110 were examined and nine individuals were classified as ‘false negatives’ according to diagnoses. Depending on reference the specificity was 97–99% and sensitivity was 14–69%.

Conclusion

Screening with DMCO demonstrated high specificity, whereas sensitivity was unsatisfactory. Future studies with enough power to estimate the true sensitivity is needed.
Planting gardens to support insect pollinators
Authors: Majewska Ania A. , Altizer Sonia
Published: December 2018

Global insect pollinator declines have prompted habitat restoration efforts, including pollinator‐friendly gardening. Gardens can provide nectar and pollen for adult insects and offer reproductive resources, such as nesting sites and caterpillar host plants. We conducted a review and meta‐analysis to examine how decisions made by gardeners on plant selection and garden maintenance influence pollinator survival, abundance, and diversity. We also considered characteristics of surrounding landscapes and the impacts of pollinator natural enemies. Our results indicated that pollinators responded positively to high plant species diversity, woody vegetation, garden size, and sun exposure and negatively to the separation of garden habitats from natural sites. Within‐garden features more strongly influenced pollinators than surrounding landscape factors. Growing interest in gardening for pollinators highlights the need to better understand how gardens contribute to pollinator conservation and how some garden characteristics can enhance the attractiveness and usefulness of gardens to pollinators. Further studies examining pollinator reproduction, resource acquisition, and natural enemies in gardens and comparing gardens with other restoration efforts and to natural habitats are needed to increase the value of human‐made habitats for pollinators.
Ionic liquid as an effective solvent for cell wall deconstructing through astaxanthin extraction from Haematococcus pluvialis
Authors: Liu Zhi‐Wei , Yue Zhou , Zeng Xin‐An , Cheng Jun‐Hu , Aadil Rana Muhammad
Published: December 2018

Haematococcus pluvialis is a proficient source of natural antioxidant astaxanthin. However, the efficient extraction of astaxanthin from this microalga remains a great challenge due to the presence of the tough and non‐hydrolysable cell walls. In this study, ionic liquid (IL) pretreatment was used for deconstruction of cell wall method. Imidazolium‐based ILs exhibited higher cell disruption capability than pyridinium‐based and ammonium‐based ILs. After the ILs determination, 1‐butyl‐3‐methylimidazolium chloride ([Bmim] Cl) was the most efficient method for cell wall deconstruction that leads to the highest astaxanthin extractability. More than 80% astaxanthin was extracted from H. pluvialis under mild conditions (pretreatment with 40% IL aqueous solution at 35 °C, followed by methanolic extraction at 50 °C). In addition, [Bmim] Cl showed the excellent recyclability, and negligible loss of astaxanthin during IL pretreatment was observed. The present work demonstrates that the combination of IL pretreatment and organic solvent extraction was an energy efficient and eco‐friendly process for the astaxanthin recovery from H. pluvialis.
Evaluation of various Bacillus coagulans isolates for the production of high purity L‐lactic acid using defatted rice bran hydrolysates
Authors: Alexandri Maria , Neu Anna‐Katrin , Schneider Roland , López‐Gómez José Pablo , Venus Joachim
Published: December 2018

Defatted rice bran (DRB) constitutes an abundant by‐product stream, generated during rice milling and subsequent bran oil extraction. Enzymatic hydrolysis of starch and protein content in DRB was optimised in terms of solid loading. Among the four solid loadings evaluated (10%, 15%, 20% and 25%), the hydrolysate derived from 20% solids resulted in the highest concentration of glucose (82.3 g L−1) and free amino nitrogen (234.8 mg L−1). The fermentability of the hydrolysate was evaluated via screening of sixteen isolates. All the strains were able to grow and produce high purity L‐lactic acid, utilising the DRB as sole carbon and nutrient source. Among the studied strains, the Bacillus coagulans A107 isolate presented the most promising results in terms of final lactic acid concentration (75.9 g L−1), yield (0.90 g g−1) and productivity (2.7 g L−1 h−1). The results of this study indicate that DRB could be employed as an inexpensive, alternative substrate for L‐lactic acid production.
Effectiveness of a protocol for teaching dental tooth color in students with color vision impairment
Authors: Wagner Sonia , Rioseco Miguel , Ortuño Duniel , Cortés María F. , Costa Carolina
Published: December 2018

Objective

In patients with color vision alterations (CVA), the correct determination of color is altered, but not the detection of changes in luminosity or value. There is no accepted training protocol for dental value selection in dental students with CVA. The objective of this pilot study was to determine the effectiveness of a dental color training protocol based on the dental value selection.

Materials and Methods

An intervention study was carried out on dental students in a University setting, applying a specific dental color training protocol on two groups of students. Group 1:4 students with CVA, Group 2:4 healthy students. A third group of four students without intervention was used as a control group. An initial diagnostic test was applied, which was reapplied at the end of the training.

Results

The number of errors in the selection of the dental color decreased after training in all three groups, P > .05. For the value parameter, there was a statistically significant decrease in the number of errors after training (P = .014).

Conclusions

The applied training protocol could be of help in students with CVA, but multicenter studies are needed.

Clinical significance

Level 3 evidence level.
The IOU Consensus Recommendations for Empirical Therapy of Cystitis in Nursing Home Residents
Authors: Hanlon Joseph T. , Perera Subashan , Drinka Paul J. , Crnich Christopher J. , Schweon Steven J. , Klein‐Fedyshin Michele , Wessel Charles B. , Saracco Stacey , Anderson Gulsum , Mulligan Mary , Nace David A.
Published: December 2018

OBJECTIVE

To establish consensus recommendations for empirical treatment of uncomplicated cystitis with anti‐infectives in noncatheterized older nursing home residents to be implemented in the Improving Outcomes of UTI Management in Long‐Term Care Project (IOU) funded by the Agency for Healthcare Research and Quality.

DESIGN

Two‐round modified Delphi survey.

PARTICIPANTS

Expert panel of 19 clinical pharmacists.

MEASUREMENTS

Comprehensive literature search and development/review/edit of draft survey by the investigative group (one geriatric clinical pharmacist, two geriatric medicine physicians, and one infectious disease physician). The expert panel members rated their agreement with each of 31 recommendations for drugs of choice, dosing medications at various levels of renal function, drug‐drug interactions to avoid, and duration of therapy by sex on a 5‐point Likert scale (1 = strongly disagree to 5 = strongly agree). Consensus agreement was defined as a lower 95% confidence limit of 4.0 or higher for the recommendation‐specific mean score.

RESULTS

The response rate was 95% for the first round, and three recommendations achieved consensus (dosing for nitrofurantoin and trimethoprim/sulfamethoxazole in those without chronic kidney disease, and drug‐drug interaction between trimethoprim/sulfamethoxazole and warfarin). In the second round, 90% responded and reached consensus on an additional eight recommendations (two for nitrofurantoin or trimethoprim/sulfamethoxazole as initial drugs of choice, three for dosing ciprofloxacin, nitrofurantoin, and trimethoprim/sulfamethoxazole at various levels of chronic kidney disease, and three drug‐drug interactions to avoid: trimethoprim/sulfamethoxazole with phenytoin and ciprofloxacin with theophylline or with tizanidine).

CONCLUSION

An expert panel of clinical pharmacists was able to reach consensus on a set of recommendations for the empirical treatment of cystitis with oral anti‐infective medications in older nursing home residents. The recommendations were incorporated into a treatment algorithm for uncomplicated cystitis in noncatheterized nursing home residents and used in educational materials for health professionals in an ongoing controlled intervention study. J Am Geriatr Soc 67:539–545, 2019.
Apolipoprotein E Genotypes, Age, Race, and Cognitive Decline in a Population Sample
Authors: Rajan Kumar B. , Barnes Lisa L. , Wilson Robert S. , Weuve Jennifer , McAninch Elizabeth A. , Evans Denis A.
Published: December 2018

OBJECTIVES

To examine the effects of age and race on the association of apolipoprotein E (APOE) genotypes with cognitive decline in a population sample.

DESIGN

Longitudinal study of 18 years’ duration.

SETTING

Biracial urban US population sample.

PARTICIPANTS

There were a total of 5807 participants, 60% African American (AA) and 40% European American (EA).

MEASUREMENTS

A composite cognitive function based on individual tests of episodic memory, perceptual speed, and the Mini‐Mental State Examination.

RESULTS

The frequencies of APOE ε2/ε3 (14% vs 12%), ε2/ε4 (4% vs 2%), ε3/ε4 (29% vs 22%), and ε4/ε4 (4% vs 2%) genotypes were higher among AAs than EAs. After adjusting for demographic factors, the rate of decline in global cognition was twice as high among participants with the APOE ε4/ε4 genotype compared to participants with the APOE ε3/ε3 genotype (0.097 vs 0.048 SD units [SDUs] per year; P < .0001). This doubling was not different between AAs (0.091 vs 0.045 SDUs per year) and EAs (0.118 vs 0.059 SDUs per year) (Pinteraction = .63). The APOE ε3/ε4 genotype was associated with a higher rate of decline with age (Pinteraction = .021), while the APOE ε2/ε4 genotype (Pinteraction = .016) and the APOE ε2/ε3 genotype (Pinteraction = .043) were associated with a lower rate of decline with higher age. The APOE ε2/ε2 genotype was associated with a lower rate of decline in episodic memory, while the APOE ε2/ε4 was associated with a higher rate of decline in episodic memory and perceptual speed.

CONCLUSIONS

The association of the APOE genotypes with cognitive decline was not different between AAs and EAs. However, individuals with different APOE genotypes showed a lower or a higher rate of decline with age. J Am Geriatr Soc 67:734–740, 2019.
Pathogenesis and prevention of risk of cardiovascular events in patients with pneumococcal community‐acquired pneumonia
Authors: Feldman C. , Normark S. , Henriques‐Normark B. , Anderson R.
Published: December 2018

It is now well recognized that cardiovascular events (CVE) occur quite commonly, both in the acute phase and in the long‐term, in patients with community‐acquired pneumonia (CAP). CVE have been noted in up to 30% of patients hospitalized with all‐cause CAP. One systematic review and meta‐analysis of hospitalized patients with all‐cause CAP noted that the incidence rates for overall cardiac events were 17.7%, for incident heart failure were 14.1%, for acute coronary syndromes were 5.3% and for incident cardiac arrhythmias were 4.7%. In the case of pneumococcal CAP, almost 20% of patients studied had one or more of these cardiac events. Recent research has provided insights into the pathogenesis of the acute cardiac events occurring in pneumococcal infections. With respect to the former, key involvements of the major pneumococcal protein virulence factor, pneumolysin, are now well documented, whilst systemic platelet‐driven neutrophil activation may also contribute. However, events involved in the pathogenesis of the long‐term cardiovascular sequelae remain largely unexplored. Emerging evidence suggests that persistent antigenaemia may predispose to the development of a systemic pro‐inflammatory/prothrombotic phenotype underpinning the risk of future cardiovascular events. The current manuscript briefly reviews the occurrence of cardiovascular events in patients with all‐cause CAP, as well as in pneumococcal and influenza infections. It highlights the close interaction between influenza and pneumococcal pneumonia. It also includes a brief discussion of mechanisms of the acute cardiac events in CAP. However, the primary focus is on the prevalence, pathogenesis and prevention of the longer‐term cardiac sequelae of severe pneumococcal disease, particularly in the context of persistent antigenaemia and associated inflammation.
Melatonin protects in vitro matured porcine oocytes from toxicity of Aflatoxin B1
Authors: Cheng Linghua , Qin Yusheng , Hu Xiao , Ren Likun , Zhang Chao , Wang Xiaodong , Wang Wenjuan , Zhang Zhenni , Hao Jin , Guo Min , Wu Zhonghong , Tian Jianhui , An Lei
Published: December 2018

Aflatoxin B1 (AFB1) is a major food and feed contaminant that threaten public health. Previous studies indicate that AFB1 exposure disrupted oocyte maturation. However, an effective and feasible method is unavailable for protecting oocytes against toxicity of AFB1. In the present study, using in vitro matured porcine oocytes and parthenogenetic embryos as model, we confirmed that AFB1 exposure during in vitro oocyte maturation (IVM) significantly impaired both nuclear and cytoplasmic maturation in a dose‐ and time‐dependent manner. The different concentrations of melatonin were also tested for their protective effects on oocytes against the AFB1‐induced toxicity. Our results showed that supplementation of a relative high concentration of melatonin (10−3mol/L) during IVM efficiently reversed the impaired development rate and blastocyst quality, to the levels comparable to those of the control group. Further analysis indicated that melatonin application efficiently alleviated reactive oxygen species accumulation and initiation of apoptosis induced by AFB1 exposure. In addition, disrupted GSH/GPX system, as well as inhibited mitochondrial DNA (mtDNA) replication and mitochondrial biogenesis in AFB1‐treated oocytes, can be notably reversed by melatonin application. Furthermore, cumulus cells may be important in mediating the toxicity of AFB1 to oocytes, and the metabolism of AFB1 in cumulus cells can be depressed by melatonin. To the best of our knowledge, this is the first report to confirm that melatonin application can efficiently protect oocytes from AFB1‐induced toxicity. Our study provides a promising and practical strategy for alleviating or reversing AFB1‐induced female reproductive toxicity in both clinical treatment and domestic reproductive management.
Effect of live yeast (Saccharomyces cerevisiae) supplementation on rumen fermentation and metabolic profile of dairy cows in early lactation
Authors: Kumprechtová Dana , Illek Josef , Julien Christine , Homolka Petr , Jančík Filip , Auclair Eric
Published: December 2018

The study evaluated dietary supplementation with live yeast (LY) Saccharomyces cerevisiae (CNCM I‐4407, 1010 CFU/g, Actisaf; Phileo Lesaffre Animal Care, France) on rumen fermentation and serum metabolic profile in lactating dairy cows. Fifty Holstein cows received a total mixed ration with (Live Yeast Diet, LYD, n = 25) or without (Control Diet, CD, n = 25) 5 × 1010 CFU/cow/day of LY from 3 to 19 weeks of lactation. Rumen fermentation and serum metabolic profile were measured in eight cows per treatment at 3, 7, 11, 15, 19 weeks post‐partum. LYD showed an increased daily milk yield (+4%) over CD (p < 0.05). Mean rumen pH at 4 hr after morning meal was higher in LYD (6.59) than CD (6.32) (p < 0.01). Total volatile fatty acids (VFA) and acetate molar proportion were higher in LYD (114.24 mM; 25.04%) than CD (106.47 mM; 24.73%) (p < 0.05). Propionate and butyrate molar proportions, acetate to propionate ratio, ammonia levels did not differ between LYD and CD. Ruminal lactate was lower in LYD than CD (9.3 vs. 16.4 mM) (p < 0.001), with a 53% decrease in LYD. During peak lactation, LYD had lower serum NEFA (p < 0.05, 0.40 vs. 0.48 mM) and BHBA (p < 0.01, 0.47 vs. 0.58 mM) than CD, lower liver enzyme activities (AST 1.39 vs. 1.54 ukat/L) (p < 0.05). Serum glucose was higher in LYD at peak lactation (3.22 vs. 3.12 mM, and 3.32 vs. 3.16 mM respectively) (p < 0.05). The results confirmed a reducing effect of LY on lactate accumulation in rumen fluid, associated with an increase in rumen pH. Lower serum levels of lipomobilization markers, liver enzyme activities and higher glucose levels may suggest that live yeast slightly mitigated negative energy balance and had a certain liver protective effect.
Drivers of the beta diversity of aquatic plant communities along a latitudinal gradient in southern Brazilian coastal ponds
Authors: Bertuzzi Tatiane , Marques Pires Mateus , Maltchik Leonardo
Published: December 2018

Questions

Is macrophyte beta diversity in temporary ponds generated mainly by turnover along a latitudinal gradient? Is macrophyte beta diversity more strongly correlated with differences in local environmental conditions and climate than geographical distances? Are hydrophytes and helophytes correlated with distinct environmental drivers?

Location

Southern Brazilian Coastal Plain.

Methods

Macrophyte communities were studied in 24 ponds distributed along a latitudinal gradient. Beta diversity was calculated with the Sorensen dissimilarity index (and further partitioned into turnover and nestedness components). We assessed the individual correspondence of macrophyte beta diversity with local (water quality and habitat structure; after pre‐selection procedures on each explanatory matrix) and climatic environmental drivers, as well as with the geographical distances, through Mantel correlation tests. Partial Mantel tests were carried out to assess the correspondence of beta diversity with the climatic drivers and geographical distances while controlling for the effect of each explanatory matrix. Separate assessments were carried out for subsets of hydrophytes and helophytes.

Results

Macrophyte beta diversity was mainly generated by turnover. Mantel tests detected significant correlations of macrophyte beta diversity with climatic rather than with local environmental drivers. Partial Mantel tests detected significant relationships only between macrophyte beta diversity and climate (rather than geographical distances). Helophytes were more strongly correlated with climate than hydrophytes, and geographical distances were significantly correlated to hydrophyte beta diversity only.

Conclusions

Our results indicate that macrophyte communities in southern Brazilian coastal temporary ponds are mainly assembled by species sorting processes, although the contribution of each assembly mechanism differed between functional groups (spatial processes were more important for hydrophytes than helophytes). The distinct relationships of hydrophytes and helophytes with climate suggest different sensitivity of each functional group to environmental changes in temporary ponds.
OsHOP2 regulates the maturation of crossovers by promoting homologous pairing and synapsis in rice meiosis
Authors: Shi Wenqing , Tang Ding , Shen Yi , Xue Zhihui , Zhang Fanfan , Zhang Chao , Ren Lijun , Liu Changzhen , Du Guijie , Li Yafei , Yan Changjie , Cheng Zhukuan
Published: December 2018

Meiotic recombination is closely linked with homologous pairing and synapsis. Previous studies have shown that HOMOLOGOUS PAIRING PROTEIN2 (HOP2), plays an essential role in homologous pairing and synapsis. However, the mechanism by which HOP2 regulates crossover (CO) formation has not been elucidated. Here, we show that OsHOP2 mediates the maturation of COs by promoting homologous pairing and synapsis in rice (Oryza sativa) meiosis.

We used a combination of genetic analysis, immunolocalization and super‐resolution imaging to analyze the function of OsHOP2 in rice meiosis.

We showed that full‐length pairing, synapsis and CO formation are disturbed in Oshop2 meiocytes. Moreover, structured illumination microscopy showed that OsHOP2 localized to chromatin and displayed considerable co‐localization with axial elements (AEs) and central elements (CEs). Importantly, the interaction between OsHOP2 and a transverse filament protein of synaptonemal complex (ZEP1), provided further evidence that OsHOP2 was involved in assembly or stabilization of the structure of the synaptonemal complex (SC). Although the initiation of recombination and CO designation occur normally in Oshop2 mutants, mature COs were severely reduced, and human enhancer of invasion 10 (HEI10)10 foci were only present on the synapsed region.

Putting the data together, we speculate that OsHOP2 may serve as a global regulator to coordinate homologous pairing, synapsis and meiotic recombination in rice meiosis.
Susceptibility patterns of uropathogens identified in hospitalized children
Authors: Kalaitzidou Ioanna , Ladomenou Fani , Athanasopoulos Emmanouil , Anatoliotaki Maria , Vlachaki Georgia
Published: December 2018

Background

Urinary tract infection (UTI) is the most common serious bacterial infection in childhood. The aim of the present study was therefore to identify the organisms responsible for community‐acquired febrile UTI in children, to investigate their susceptibility to commonly used antibiotics, and to identify possible risk factors for antibiotic resistance.

Methods

A total of 284 children (male, 38%; female, 62%), who were hospitalized due to a community‐acquired UTI over a 5 year period in a general district hospital of southern Greece, were enrolled in the study.

Results

Escherichia coli was the leading uropathogen followed by Klebsiella spp. (9.15%) and Proteus spp. (5.28%). E. coli isolates were most commonly resistant to ampicillin (41.8%), followed by piperacillin (40.3%), amoxicillin‐clavulanic acid (28.6%) and trimethoprim‐sulfamethoxazole (17.8%), while 27 strains (12.6%) were multi‐drug resistant (MDR). Of the E. coli strains, 4.21% were producing extended‐spectrum beta‐lactamases. Parenteral second‐ and third‐generation cephalosporins, the most commonly used antibiotic agents (81.3%) in the present cohort, remained highly active against E. coli and other urinary isolates, given that >95% of E. coli strains were susceptible to cefuroxime and cefotaxime. Vesicoureteral reflux was a significant risk factor for MDR (P = 0.04).

Conclusion

Contrary to current local practice, amoxicillin/clavulanic acid may not be the best option for the empirical treatment of community‐acquired UTI in southern Greece.
Reticulocyte hemoglobin equivalent in a thalassemia‐prevalent area
Authors: Kadegasem Praguywan , Songdej Duantida , Lertthammakiat Surapong , Chuansumrit Ampaiwan , Paisooksantivatana Karan , Mahaklan Lalita , Wongwerawattanakoon Pakawan , Tangbubpha Noppawan , Sirachainan Nongnuch
Published: December 2018

Background

Reticulocyte hemoglobin equivalent (Ret‐He), a direct measure of the hemoglobin (Hb) in the young red blood cells, has been reported to be useful in the diagnosis of iron deficiency anemia (IDA) but may have some limitations in thalassemia trait. This study evaluated the differences in Ret‐He in school‐aged children, and assessed the diagnostic value of Ret‐He in identifying IDA in a thalassemia‐prevalent area.

Methods

Blood samples underwent complete blood count analysis, including Ret‐He, ferritin, serum iron and total iron binding capacity. Blood samples also underwent Hb typing and a molecular study for α‐thalassemia. Receiver operating characteristic analysis was performed to determine the predictive capacity of Ret‐He in the diagnosis of IDA. ID was defined as serum ferritin <30 ng/mL and/or transferrin saturation (TSAT) <16%; IDA was defined as serum ferritin <12 ng/mL and/or TSAT <16% with low Hb for age. Normal healthy children (normal controls: NC) had normal iron study, without the thalassemia trait.

Results

Ninety‐eight children with a mean age of 12.9 ± 0.6 years were included. Ret‐He in the thalassemia trait group (26.7 ± 2.4 pg), ID group (29.0 ± 2.9 pg), IDA group (25.4 ± 2.7 pg), ID + thalassemia trait group (26.6 ± 2.8 pg), and the IDA + thalassemia trait group (24.6 ± 2.3 pg) was significantly lower than in the NC group (30.8 ± 1.7 pg; P < 0.001, 0.01, 0.006, 0.002 and <0.001, respectively). Ret‐He had an area under the curve of 0.904 in diagnostic ability for IDA, while a cut‐off ≤27 pg had a sensitivity of 91.7% and a specificity of 81%.

Conclusion

Ret‐He was lowest in subjects with IDA + thalassemia trait. A Ret‐He cut‐off ≤27 pg was suggestive of IDA in the present study.
Recent advances in the understanding of transient abnormal myelopoiesis in Down syndrome
Authors: Watanabe Kenichiro
Published: December 2018

Neonates with Down syndrome (DS) have a propensity to develop the unique myeloproliferative disorder, transient abnormal myelopoiesis (TAM). TAM usually resolves spontaneously in ≤3 months, but approximately 10% of patients with TAM die from hepatic or multi‐organ failure. After remission, 20% of patients with TAM develop acute myeloid leukemia associated with Down syndrome (ML‐DS). Blasts in both TAM and ML‐DS have trisomy 21 and GATA binding protein 1 (GATA1) mutations. Recent studies have shown that infants with DS and no clinical signs of TAM or increases in peripheral blood blasts can have minor clones carrying GATA1 mutations, referred to as silent TAM. Low‐dose cytarabine can improve the outcomes of patients with TAM and high white blood cell count. A number of studies using fetal liver cells, mouse models, or induced pluripotent stem cells have elucidated the roles of trisomy 21 and GATA1 mutations in the development of TAM. Next‐generation sequencing of TAM and ML‐DS patient samples identified additional mutations in genes involved in epigenetic regulation. Xenograft models of TAM demonstrate the genetic heterogeneity of TAM blasts and mimic the process of clonal selection and expansion of TAM clones that leads to ML‐DS. DNA methylation analysis suggests that epigenetic dysregulation may be involved in the progression from TAM to ML‐DS. Unraveling the mechanisms underlying leukemogenesis and identification of factors that predict progression to leukemia could assist in development of strategies to prevent progression to ML‐DS. Investigation of TAM, a unique pre‐leukemic condition, will continue to strongly influence basic and clinical research into the development of hematological malignancies.
Dynamics of plant responses to combinations of air pollutants
Authors: Papazian S. , Blande J. D.
Published: December 2018

The focus of this review is on how plants respond to combinations of multiple air pollutants. Global pollution trends, plant physiological responses and ecological perspectives in natural and agricultural systems are all discussed. In particular, we highlight the importance of studying sequential or simultaneous exposure of plants to pollutants, rather than exposure to individual pollutants in isolation, and explore how these responses may interfere with the way plants interact with their biotic community. Air pollutants can alter the normal physiology and metabolic functioning of plants. Here we describe how the phenotypic and molecular changes in response to multiple pollutants can differ compared to those elicited by single pollutants, and how different responses have been observed between plants in the field and in controlled laboratory conditions and between trees and crop plants. From an ecological perspective, we discuss how air pollution can result in greater susceptibility to biotic stressors and in direct or indirect effects on interactions with organisms that occupy higher trophic levels. Finally, we provide an overview of the potential uses of plants to mitigate air pollution, exploring the feasibility for pollution removalviathe processes of bio‐accumulation and phytoremediation. We conclude by proposing some new directions for future research in the field.
Presidential Preview: Nixon’s Vice Presidency and Role in the Vietnam War, 1953–1955
Authors: Neale Ashley L.
Published: December 2018

Despite President Richard M. Nixon’s own statements that his time within the administration of Dwight D. Eisenhower was influential to his thinking on foreign policy, only recently has the relationship between Eisenhower and Nixon actually been examined. This article explores Nixon’s experiences as vice president under Eisenhower, including Nixon’s role in policy making. From there, this article illustrates the important role that Nixon’s time as vice president played in shaping his approach to the war in Vietnam and to the very policy‐making processes he created in his own administration to debate, produce, and implement foreign policy.
Targeted exome sequencing of unselected heavy‐ion beam‐irradiated populations reveals less‐biased mutation characteristics in the rice genome
Authors: Ichida Hiroyuki , Morita Ryouhei , Shirakawa Yuki , Hayashi Yoriko , Abe Tomoko
Published: December 2018

Heavy‐ion beams have been widely utilized as a novel and effective mutagen for mutation breeding in diverse plant species, but the induced mutation spectrum is not fully understood at the genome scale. We describe the development of a multiplexed and cost‐efficient whole‐exome sequencing procedure in rice, and its application to characterize an unselected population of heavy‐ion beam‐induced mutations. The bioinformatics pipeline identified single‐nucleotide mutations as well as small and large (>63 kb) insertions and deletions, and showed good agreement with the results obtained with conventional polymerase chain reaction (PCR) and sequencing analyses. We applied the procedure to analyze the mutation spectrum induced by heavy‐ion beams at the population level. In total, 165 individual M2 lines derived from six irradiation conditions as well as eight pools from non‐irradiated ‘Nipponbare’ controls were sequenced using the newly established target exome sequencing procedure. The characteristics and distribution of carbon‐ion beam‐induced mutations were analyzed in the absence of bias introduced by visual mutant selections. The average (±SE) number of mutations within the target exon regions was 9.06 ± 0.37 induced by 150 Gy irradiation of dry seeds. The mutation frequency changed in parallel to the irradiation dose when dry seeds were irradiated. The total number of mutations detected by sequencing unselected M2 lines was correlated with the conventional mutation frequency determined by the occurrence of morphological mutants. Therefore, mutation frequency may be a good indicator for sequencing‐based determination of the optimal irradiation condition for induction of mutations.