bluuebunny/crossref_metadata_2025 huggingface dataset:
Regulation of calcium dynamics and propagation velocity by tissue microstructure in engineered strands of cardiac tissue
Authors: Petersen Andrew P , Cho Nathan , Lyra-Leite Davi M , Santoso Jeffrey W , Gupta Divya , Ariyasinghe Nethika R , McCain Megan L
Published: March 2020

Disruptions to cardiac tissue microstructure are common in diseased or injured myocardium and are known substrates for arrhythmias. However, we have a relatively coarse understanding of the relationships between myocardial tissue microstructure, propagation velocity and calcium cycling, due largely to the limitations of conventional experimental tools. To address this, we used microcontact printing to engineer strands of cardiac tissue with eight different widths, quantified several structural and functional parameters and established correlation coefficients. As strand width increased, actin alignment, nuclei density, sarcomere index and cell aspect ratio decreased with unique trends. The propagation velocity of calcium waves decreased and the rise time of calcium transients increased with increasing strand width. The decay time constant of calcium transients decreased and then slightly increased with increasing strand width. Based on correlation coefficients, actin alignment was the strongest predictor of propagation velocity and calcium transient rise time. Sarcomere index and cell aspect ratio were also strongly correlated with propagation velocity. Actin alignment, sarcomere index and cell aspect ratio were all weak predictors of the calcium transient decay time constant. We also measured the expression of several genes relevant to propagation and calcium cycling and found higher expression of the genes that encode for connexin 43 (Cx43) and a subunit of L-type calcium channels in thin strands compared to isotropic tissues. Together, these results suggest that thinner strands have higher values of propagation velocity and calcium transient rise time due to a combination of favorable tissue microstructure and enhanced expression of genes for Cx43 and L-type calcium channels. These data are important for defining how microstructural features regulate intercellular and intracellular calcium handling, which is needed to understand mechanisms of propagation in physiological situations and arrhythmogenesis in pathological situations.
Whole-genome analyses identify loci and selective signals associated with body size in cattle
Authors: Chen Qiuming , Huang Bizhi , Zhan Jingxi , Wang Junjie , Qu Kaixing , Zhang Fengwei , Shen Jiafei , Jia Peng , Ning Qingqing , Zhang Jicai , Chen Ningbo , Chen Hong , Lei Chuzhao
Published: March 2020

Body size plays a key role in production, health, selection, and environmental adaptation of animals, but the genetic basis of body size variation is not clearly understood. Here, we conducted genome-wide association studies (GWAS) of 15 body size traits using autosomal single nucleotide polymorphisms (SNPs) derived from whole-genome sequences of 31 Brahman cattle and 131 Yunling cattle and identified 20 significant loci, which implicated 18 candidate genes. For ischium width, the most significant SNP was assigned to LCORL, a famous gene controlling body size. For chest width, the most significant SNP was located upstream of BMP5, a secreted ligand of transformation growth factor-beta superfamily of proteins involved in bone and cartilage development. Subsequently, we detected selective sweeps in Brahman cattle using integrated Haplotype Score, composite likelihood ratio, and nucleotide diversity. The results showed CNTNAP5 locus associated with hip cross height and LIMCH1 locus associated with forehead size were in selective signals, which were consistent with higher hip cross height and higher forehead size in Brahman cattle compared with Yunling cattle. Our findings provide genetic insights into variation and selection of body size using GWAS and selective signals and will accelerate future efforts aimed at cattle improvement.
A comparison of methods for estimating forage intake, digestibility, and fecal output in red deer (Cervus elaphus)
Authors: Garrett Konagh , Beck Matt R , Froehlich Kelly , Fleming Anita , Thompson Bryan R , Stevens David R , Gregorini Pablo
Published: March 2020

The objective of this experiment was to determine appropriate methods for estimating fecal output, digestibility, and intake in red deer (Cervus elaphus). Dry matter intake (DMI), digestibility, and fecal output were estimated using the dual-marker (titanium dioxide; TiO2 and indigestible acid detergent fiber) technique, double n-alkane ratio technique (ALK) and the pulse dose (Yttrium; Y) technique to determine a suitable method to estimate DMI, fecal output, and digestibility measurements. Four male and four female deer were stratified by sex and randomly assigned either fresh-cut perennial ryegrass (Lolium perenne L.) or fresh-cut plantain (Plantago lanceolata) ad libitum in a cross-over design experiment. Actual DMI (mean ± SD: 1.5 ± 0.36 kg DM/d), digestibility (0.70 ± 0.06), and fecal output (0.45 ± 0.1 kg DM/d) were measured daily over the collection periods, and the average of each period was used for methods’ comparison. The ALK method adequately estimated digestibility and fecal output of plantain; however, overestimated digestibility (P < 0.05) and DMI of ryegrass, so that there was no statistical agreement (P > 0.10) in DMI when diets were pooled. The overestimated DMI of the ryegrass diet led to ALK predicting greater intake when deer consumed ryegrass than plantain, which was the opposite of actual measurements. The pulse dosed Y overestimated (P < 0.05) fecal output and consequently DMI for both plantain and ryegrass, however, indicated similar trends to actual values. The dual-marker technique using TiO2 was able to detect the statistical differences between plantain and ryegrass as the actual measurements, had moderate to strong precision (r = 0.50 to 0.66) and statistical agreement (P < 0.05) with the pooled diet data. Therefore, the dual-marker technique provided the best alternative estimation method to actual measurements of forage DMI of grazing red deer.
Kripkeans of the world, unite!
Authors: Islam Farjana , Baggio Giosuè
Published: March 2020

This paper revisits a study by Machery et al. (2004), suggesting that, in experimental versions of Kripke’s (1980) fictional cases on the use of proper names, Westerners are more likely than East Asian participants to show intuitions compatible with Kripke’s causal-historical (CH) theory of reference. We conducted two experiments, recruting participants from Norway and Bangladesh, either in English (experiment 1; N = 75) or in the participants’ native languages (experiment 2; N = 60), using modified cases and a new approach to data analysis. We replicated the results of Machery et al. (2004), but we show that the residual finding—i.e., that participants who are not aligned with CH produce responses consistent with a definite descriptions (DD) theory of reference—does not hold. Most participants in our experiments, and nearly all those who do not provide CH answers, respond as predicted by a theory that accommodates speaker’s reference in reasoning about uses of proper names, not according to DD. We suggest that cross-cultural variation in this task is real. However, explanations of variation within or across cultures need not invoke competing theories of reference (CH vs DD), and can be unified within a single, broadly Kripkean analysis that honors the basic distinction between semantic reference and speaker’s reference.
EARLY BUD BREAK 1 triggers bud break in peach trees by regulating hormone metabolism, the cell cycle, and cell wall modifications
Authors: Zhao Xuehui , Han Xiaolun , Wang Qingjie , Wang Xuxu , Chen Xiude , Li Ling , Fu Xiling , Gao Dongsheng
Published: March 2020

In a previous study we identified EARLY BUD BREAK 1 (EBB1), an ERF transcription factor, in peach (Prunus persica var. nectarina cultivar Zhongyou 4); however, little is known of how PpEBB1 may regulate bud break. To verify the function of PpEBB1 in bud break, PpEBB1 was transiently transformed into peach buds, resulting in early bud break. Bud break occurred earlier in PpEBB1-oe poplar (Populus trichocarpa) obtained by heterologous transformation than in wild type (WT), consistent with the peach bud results, indicating that PpEBB1 can promote bud break. To explore how PpEBB1 affects bud break, differentially expressed genes (DEGs) between WT and PpEBB1-oe poplar plants were identified by RNA-sequencing. The expression of DEGs associated with hormone metabolism, cell cycle, and cell wall modifications changed substantially according to qRT-PCR. Auxin, ABA, and total trans-zeatin-type cytokinin levels were higher in the PpEBB1-oe plants than in WT plants, while the total N6-(Δ 2-isopentenyl)-adenine-type cytokinins was lower. Yeast two-hybrid and bimolecular fluorescence complementation assays verified that a cell wall modification-related protein (PpEXBL1) interacted with PpEBB1 suggesting that PpEBB1 could interact with these cell wall modification proteins directly. Overall, our study proposed a multifaceted explanation for how PpEBB1 regulates bud break and showed that PpEBB1 promotes bud break by regulating hormone metabolism, the cell cycle, and cell wall modifications.
Phosphorylation of a malate transporter promotes malate excretion and reduces cadmium uptake in apple
Authors: Ma Qi-Jun , Sun Mei-Hong , Lu Jing , Hu Da-Gang , Kang Hui , You Chun-Xiang , Hao Yu-Jin
Published: March 2020

Heavy metal contamination is a major environmental and human health hazard in many areas of the world. Organic acids sequester heavy metals and protect plant roots from the effects of toxicity; however, it is largely unknown how these acids are regulated in response to heavy metal stress. Here, protein kinase SOS2L1 from apple was functionally characterized. MdSOS2L1 was found to be involved in the regulation of malate excretion, and to inhibit cadmium uptake into roots. Using the DUAL membrane system in a screen of an apple cDNA library with MdSOS2L1 as bait, a malate transporter, MdALMT14, was identified as an interactor. Bimolecular fluorescence complementation, pull-down, and co-immunoprecipitation assays further indicated the interaction of the two proteins. Transgenic analyses showed that MdSOS2L1 is required for cadmium-induced phosphorylation at the Ser358 site of MdALMT14, a modification that enhanced the stability of the MdALMT14 protein. MdSOS2L1 was also shown to enhance cadmium tolerance in an MdALMT14-dependent manner. This study sheds light on the roles of the MdSOS2L1–MdALMT14 complex in physiological responses to cadmium toxicity.
Revisiting floral fusion: the evolution and molecular basis of a developmental innovation
Authors: Phillips Heather R , Landis Jacob B , Specht Chelsea D
Published: March 2020

Throughout the evolution of the angiosperm flower, developmental innovations have enabled the modification or elaboration of novel floral organs enabling subsequent diversification and expansion into new niches, for example the formation of novel pollinator relationships. One such developmental innovation is the fusion of various floral organs to form complex structures. Multiple types of floral fusion exist; each type may be the result of different developmental processes and is likely to have evolved multiple times independently across the angiosperm tree of life. The development of fused organs is thought to be mediated by the NAM/CUC3 subfamily of NAC transcription factors, which mediate boundary formation during meristematic development. The goal of this review is to (i) introduce the development of fused floral organs as a key ‘developmental innovation’, facilitated by a change in the expression of NAM/CUC3 transcription factors; (ii) provide a comprehensive overview of floral fusion phenotypes amongst the angiosperms, defining well-known fusion phenotypes and applying them to a systematic context; and (iii) summarize the current molecular knowledge of this phenomenon, highlighting the evolution of the NAM/CUC3 subfamily of transcription factors implicated in the development of fused organs. The need for a network-based analysis of fusion is discussed, and a gene regulatory network responsible for directing fusion is proposed to guide future research in this area.
Rapid regulation of photosynthetic light harvesting in the absence of minor antenna and reaction centre complexes
Authors: Saccon Francesco , Giovagnetti Vasco , Shukla Mahendra K , Ruban Alexander V
Published: March 2020

Plants are subject to dramatic fluctuations in the intensity of sunlight throughout the day. When the photosynthetic machinery is exposed to high light, photons are absorbed in excess, potentially leading to oxidative damage of its delicate membrane components. A photoprotective molecular process called non-photochemical quenching (NPQ) is the fastest response carried out in the thylakoid membranes to harmlessly dissipate excess light energy. Despite having been intensely studied, the site and mechanism of this essential regulatory process are still debated. Here, we show that the main NPQ component called energy-dependent quenching (qE) is present in plants with photosynthetic membranes largely enriched in the major trimeric light-harvesting complex (LHC) II, while being deprived of all minor LHCs and most photosystem core proteins. This fast and reversible quenching depends upon thylakoid lumen acidification (ΔpH). Enhancing ΔpH amplifies the extent of the quenching and restores qE in the membranes lacking PSII subunit S protein (PsbS), whereas the carotenoid zeaxanthin modulates the kinetics and amplitude of the quenching. These findings highlight the self-regulatory properties of the photosynthetic light-harvesting membranes in vivo, where the ability to switch reversibly between the harvesting and dissipative states is an intrinsic property of the major LHCII.
The emotional journey of motherhood in migration. The case of Southern European mothers in Norway
Authors: Herrero-Arias Raquel , Hollekim Ragnhild , Haukanes Haldis , Vagli Åse
Published: March 2020

Based on focus group discussions and in-depth interviews with Greek, Italian, and Spanish mothers living in Norway, this article contributes to an emerging body of literature on the role of emotions in migration by exploring migrant motherhood as an emotional journey. Drawing on the work of Arlie Hochschild on emotions and her theoretical concepts of framing rules, feeling rules, and emotion work, the article explores how migrant mothers reflect on their emotions when raising their children in the context of migration. Migrant mothers’ accounts illustrate the ambivalent and contradictory emotional experiences they have when they manage rules about how they should make sense of, and feel about their mothering in both host and origin countries. Emotions of guilt, blame, remorse, pride, satisfaction, confidence, and happiness shaped mothers’ experiences of motherhood and social interactions across countries. Through emotion work, migrant mothers managed interdependent emotions and related to different feeling rules establishing and maintaining relationships across places, and negotiating, in this way, their belonging to multiple contexts. Using an emotions-based sociological perspective, we look at motherhood as a field for studying the functions of emotions and their interactions in the context of migration.
Into the Ly α jungle: exploring the circumgalactic medium of galaxies at z ∼ 4−5 with MUSE
Authors: Bielby Richard M , Fumagalli Michele , Fossati Matteo , Rafelski Marc , Oppenheimer Benjamin , Cantalupo Sebastiano , Christensen Lise , Fynbo J P U , Lopez Sebastian , Morris Simon L , D’Odorico Valentina , Peroux Celine
Published: March 2020

We present a study of the galaxy environment of nine strong H i + C iv absorption line systems (16.2 < log(N(HI)) < 21.2) spanning a wide range in metallicity at z ∼ 4−5, using MUSE integral field and X-Shooter spectroscopic data collected in a z ≈ 5.26 quasar field. We identify galaxies within a 250 kpc and ±1000 km s−1 window for six out of the nine absorption systems, with two of the absorption line systems showing multiple associated galaxies within the MUSE field of view. The space density of Ly α emitting galaxies (LAEs) around the H i and C iv systems is ≈10−20 times the average sky density of LAEs given the flux limit of our survey, showing a clear correlation between the absorption and galaxy populations. Further, we find that the strongest C iv systems in our sample are those that are most closely aligned with galaxies in velocity space, i.e. within velocities of ±500 km s−1. The two most metal-poor systems lie in the most dense galaxy environments, implying we are potentially tracing gas that is infalling for the first time into star-forming groups at high redshift. Finally, we detect an extended Ly α nebula around the z ≈ 5.26 quasar, which extends up to ≈50 kpc at the surface brightness limit of 3.8 × 10−18 erg s−1 cm−2 arcsec−2. After scaling for surface brightness dimming, we find that this nebula is centrally brighter, having a steeper radial profile than the average for nebulae studied at z ∼ 3 and is consistent with the mild redshift evolution seen from z ≈ 2.
Planetesimals in rarefied gas: wind erosion in slip flow
Authors: Demirci Tunahan , Schneider Niclas , Steinpilz Tobias , Bogdan Tabea , Teiser Jens , Wurm Gerhard
Published: March 2020

A planetesimal moves through the gas of its protoplanetary disc where it experiences a head wind. Though the ambient pressure is low, this wind can erode and ultimately destroy the planetesimal if the flow is strong enough. For the first time, we observe wind erosion in ground-based and microgravity experiments at pressures relevant in protoplanetary discs, i.e. down to $10^{-1}\, \rm mbar$. We find that the required shear stress for erosion depends on the Knudsen number related to the grains at the surface. The critical shear stress to initiate erosion increases as particles become comparable to or larger than the mean free path of the gas molecules. This makes pebble pile planetesimals more stable at lower pressure. However, it does not save them as the experiments also show that the critical shear stress to initiate erosion is very low for sub-millimetre-sized grains.
S2COSMOS: Evolution of gas mass with redshift using dust emission
Authors: Millard Jenifer S , Eales Stephen A , Smith M W L , Gomez H L , Małek K , Simpson J M , Peng Y , Sawicki M , Beeston R A , Bunker Andrew , Ao Y , Babul A , Ho L C , Hwang Ho Seong , Michałowski M J , Scoville N , Shim H , Toba Y
Published: March 2020

We investigate the evolution of the gas mass fraction for galaxies in the COSMOS field using submillimetre emission from dust at 850 μm. We use stacking methodologies on the 850  μm S2COSMOS map to derive the gas mass fraction of galaxies out to high redshifts, 0 ≤ z ≤ 5, for galaxies with stellar masses of $10^{9.5} \lt M_* (\rm M_{\odot }) \lt 10^{11.75}$. In comparison to previous literature studies we extend to higher redshifts, include more normal star-forming galaxies (on the main sequence), and also investigate the evolution of the gas mass fraction split by star-forming and passive galaxy populations. We find our stacking results broadly agree with scaling relations in the literature. We find tentative evidence for a peak in the gas mass fraction of galaxies at around z ∼ 2.5–3, just before the peak of the star formation history of the Universe. We find that passive galaxies are particularly devoid of gas, compared to the star-forming population. We find that even at high redshifts, high stellar mass galaxies still contain significant amounts of gas.
One concept does not fit all: the immune system in different forms of acute kidney injury
Authors: Anders Hans-Joachim , Wilkens Louise , Schraml Barbara , Marschner Julian
Published: March 2020

Renal and immune systems maintain body homoeostasis during physiological fluctuations and following tissue injury. The immune system plays a central role during acute kidney injury (AKI), adapting evolutional systems programmed for host defence and minimizing unnecessary collateral damage. Indeed, depending upon the disease context, the impact of the immune system upon the manifestations and consequences of AKI can be quite different. Here we provide an overview of the known and unknown involvement of the immune system within the wide range of different forms of AKI, to oppose oversimplification and to endorse deeper insights into the pathogenesis of the different diseases causing kidney injury. This approach may help to overcome some of the current hurdles in translational AKI research and the development of specific treatments for the different diseases, all presenting with an acute increase in serum creatinine or decline in urinary output. One concept does not fit all.
β-blocker dialyzability and the risk of mortality and cardiovascular events in patients undergoing hemodialysis
Authors: Wu Ping-Hsun , Lin Yi-Ting , Kuo Mei-Chuan , Liu Jia-Sin , Tsai Yi-Chun , Chiu Yi-Wen , Carrero Juan-Jesus
Published: March 2020

Background

β-blocker (BB) dialyzability has been proposed to limit their efficacy among hemodialysis (HD) patients. We attempted to confirm this hypothesis by comparing health outcomes associated with the initiation of dialyzable or nondialyzable BBs in a nationwide cohort of HD patients.

Methods

We created a prospective cohort study of 15 699 HD patients who initiated dialyzable BBs (atenolol, acebutolol, metoprolol and bisoprolol) and 20 904 hemodialysis patients who initiated nondialyzable BBs (betaxolol, carvedilol and propranolol) between 2004 and 2011 in Taiwan healthcare. We compared the risk of all-cause mortality and major adverse cardiovascular events (MACEs, a composite of the acute coronary syndrome, ischemic stroke and heart failure) between users of dialyzable versus nondialyzable BBs during a 2-year follow-up.

Results

New users of dialyzable BBs were younger, more often men, with diabetes mellitus, hypertension and hyperlipidemia compared with users of nondialyzable BBs. Compared with nondialyzable BBs, initiation of dialyzable BBs was associated with lower all-cause mortality {hazard ratio [HR] 0.82 [95% confidence interval (CI) 0.75–0.88]} and lower risk of MACEs [HR 0.89 (95% CI 0.84–0.93)]. Results were confirmed in subgroup analyses, censoring at BB discontinuation or switch, after 1:1 propensity score matching, reclassifying bisoprolol or excluding bisoprolol/carvedilol users.

Conclusions

This study does not offer support for the hypothesis that the dialyzability of BBs reduces their efficacy in HD patients.
OsMYB80 Regulates Anther Development and Pollen Fertility by Targeting Multiple Biological Pathways
Authors: Pan Xiaoying , Yan Wei , Chang Zhenyi , Xu Yingchao , Luo Ming , Xu Chunjue , Chen Zhufeng , Wu Jianxin , Tang Xiaoyan
Published: March 2020

Pollen development is critical to the reproductive success of flowering plants, but how it is regulated is not well understood. Here, we isolated two allelic male-sterile mutants of OsMYB80 and investigated how OsMYB80 regulates male fertility in rice. OsMYB80 was barely expressed in tissues other than anthers, where it initiated the expression during meiosis, reached the peak at the tetrad-releasing stage and then quickly declined afterward. The osmyb80 mutants exhibited premature tapetum cell death, lack of Ubisch bodies, no exine and microspore degeneration. To understand how OsMYB80 regulates anther development, RNA-seq analysis was conducted to identify genes differentially regulated by OsMYB80 in rice anthers. In addition, DNA affinity purification sequencing (DAP-seq) analysis was performed to identify DNA fragments interacting with OsMYB80 in vitro. Overlap of the genes identified by RNA-seq and DAP-seq revealed 188 genes that were differentially regulated by OsMYB80 and also carried an OsMYB80-interacting DNA element in the promoter. Ten of these promoter elements were randomly selected for gel shift assay and yeast one-hybrid assay, and all showed OsMYB80 binding. The 10 promoters also showed OsMYB80-dependent induction when co-expressed in rice protoplast. Functional annotation of the 188 genes suggested that OsMYB80 regulates male fertility by directly targeting multiple biological processes. The identification of these genes significantly enriched the gene networks governing anther development and provided much new information for the understanding of pollen development and male fertility.
Does Choice Really Imply Excluded Middle? Part II: Historical, Philosophical, and Foundational Reflections on the Goodman–Myhill Result†
Authors: Tennant Neil
Published: March 2020

Our regimentation of Goodman and Myhill’s proof of Excluded Middle revealed among its premises a form of Choice and an instance of Separation.

Here we revisit Zermelo’s requirement that the separating property be definite. The instance that Goodman and Myhill used is not constructively warranted. It is that principle, and not Choice alone, that precipitates Excluded Middle.

Separation in various axiomatizations of constructive set theory is examined. We conclude that insufficient critical attention has been paid to how those forms of Separation fail, in light of the Goodman–Myhill result, to capture a genuinely constructive notion of set.
Risk Factors for Psychotic Relapse After Dose Reduction or Discontinuation of Antipsychotics in Patients With Chronic Schizophrenia: A Systematic Review and Meta-analysis
Authors: Bogers Jan P A M , Hambarian George , Michiels Maykel , Vermeulen Jentien , de Haan Lieuwe
Published: March 2020

High doses of antipsychotics in patients with chronic schizophrenia might lead to more severe side effects and possibly hamper recovery, but dose reduction carries the risk of psychotic relapse. It would be helpful to establish risk factors for relapse during dose reduction. We systematically searched MEDLINE, EMBASE, and PsycINFO from January 1950 through June 2019 and reviewed studies that reported on relapse rates (event rates [ERs]) after dose reduction or discontinuation of antipsychotics in cohorts of patients with chronic schizophrenia. We calculated ERs (with 95% CIs) per person-year and sought to identify potential risk factors, such as patient characteristics, dose reduction/discontinuation characteristics, and study characteristics. Of 165 publications, 40 describing dose reduction or discontinuation in 46 cohorts (1677 patients) were included. The pooled ER for psychotic relapse was 0.55 (95% CI 0.46–0.65) per person-year. The ER was significantly higher in inpatients, patients with a shorter duration of illness, patients in whom antipsychotics were discontinued or in whom the dose was reduced to less than 5 mg haloperidol equivalent, studies with a short follow-up or published before 1990, and studies in which relapse was based on clinical judgment (ie, rating scales were not used). Clinicians should consider several robust risk factors for psychotic relapse in case of dose reduction in chronic schizophrenia.
‘A Strong International Spirit’: The Influence of Internationalism on the Women’s Co-operative Guild
Authors: Hellawell Sarah
Published: March 2020

This article explores the internationalism of the Women’s Co-operative Guild (WCG) during the interwar years. Drawing on the records of the national and international Guild, alongside the minute books of a local branch based in Darlington, County Durham, it positions the WCG in the vibrant political culture in Britain during the 1920s and 1930s. Building on recent literature that has sought to examine the phenomenon of interwar internationalism, this article sheds light on an organization that represented the interests of working-class women. Internationalist in outlook, the association demonstrates how internationalist ideals played out on a day-to-day basis. The article demonstrates that the WCG played a unique and complementary role within both the British and international women’s movements.
Identification and Functional Verification of Differences in Phenolic Compounds Between Resistant and SusceptiblePopulusSpecies
Authors: Li Yongxia , Zhang Wei , Sun Ningning , Wang Xuan , Feng Yuqian , Zhang Xingyao
Published: March 2020

Poplar canker, mainly caused by Botryosphaeria species, is a serious disease that has resulted in the reduced productivity and death of poplar worldwide. Different Populus species have varied resistance levels to poplar canker; however, whether phenolic compounds in poplar are involved in this resistance remains uncertain. Here, we determined the concentrations of phenolic compounds and their antifungal activities in canker-resistant P. tomentosa and canker-susceptible P. beijingensis. We identified 29 phenolic compounds with significantly different concentrations between the two species. Salicylic acid (SA), tremuloidin, salicin, and poplin were dominant in P. tomentosa, while benzoic acid (BA) and catechol were dominant in P. beijingensis. These six phenolic compounds were further tested for antifungal activities. SA, BA, and catechol showed significant antifungal activities against Botryosphaeria dothidea, while the other three compounds showed no activity. As BA or catechol can be converted in plants to SA, which is a remote signaling molecule that plays an important role in plant defenses, we presumed that the resistance of P. tomentosa was initiated by SA, while the susceptibility of P. beijingensis resulted from the absence of SA. Further studies are required to confirm this hypothesis. These results provide a foundation for future research on the disease-resistance mechanisms of poplar.
What Keeps Neonatal Nurses Up at Night and What Gets Them Up in the Morning?
Authors: Walden Marlene , Janssen Dalton W. , Lovenstein Austin
Published: March 2020

Background:

Occupational stress in neonatal nursing is a significant professional concern. Prolonged exposure to morally distressing patient care experiences and other healthcare issues may lead to worry among nurses. When worry becomes excessive, nurses and advanced practice registered nurses may lose joy that gives meaning to their work. Enhancing meaning in work may have a positive impact on nurse satisfaction, engagement, productivity, and burnout.

Purpose:

To explore neonatal nurses' top professional satisfiers and top professional worries and concerns.

Methods:

A descriptive study was conducted in a convenience sample of neonatal nurses to identify the top professional satisfiers that get them up in the morning and the top professional worries and concerns that keep them awake at night.

Results:

Complete data were available for 29 neonatal nurses. The top professional satisfiers were caring for infants and families, making a difference, witnessing resilience, intellectual challenge of specialty, positive working relationships with colleagues, and educating parents and families. The top professional worries and concerns were staffing, missed care, workload, making a mistake, and failure to rescue.

Implications for Practice:

Healthcare and professional organizations must develop strategies to address occupational stress in today's complex healthcare environment. Identifying professional worries and concerns may help nurses navigate challenging and distressing situations. Furthermore, understanding nurses' professional satisfiers may promote personal and professional resiliency and help organizations create healthier workplace environments.

Implications for Research:

Future studies are needed to test effective interventions that may promote professional satisfaction and help neonatal nurses cope with occupational stressors.
Correction of Genu Valgum in Patients With Congenital Fibular Deficiency
Authors: Westberry David E. , Carpenter Ashley M. , Prodoehl Julia
Published: March 2020

Background:

Patients with congenital fibular deficiency often develop genu valgum secondary to lateral femoral condylar hypoplasia. Guided growth strategies are often performed to correct limb alignment when adequate skeletal growth remains.

Methods:

A retrospective review of patients with postaxial hypoplasia of the lower extremity managed with an amputation strategy and who had a guided growth procedure for coronal plane limb malalignment during their course of treatment was performed. Clinical and radiographic data, including measures of coronal plane deformity and alignment, type of amputation, subsequent operative procedures, and complications were recorded.

Results:

Seventeen patients (20 extremities) met study inclusion criteria (mean follow-up 8.8 y). Foot ablation and hemiepiphysiodesis for valgus deformity of the knee was performed in all extremities. The average age at the time of initial hemiepiphysiodesis was 11.2 years at an average of 8.8 years from the initial amputation procedure. The mean preoperative mechanical axis deviation was 26.5 mm, which was corrected to a mean mechanical axis deviation of 7.0 mm. Fifteen (75%) of the extremities had correction of the deformity to neutral alignment after the initial procedure. Lack of correction occurred in 3 extremities, and overcorrection occurred in 2 extremities. Additional procedures were required in 5 extremities for rebound valgus deformity after hardware removal.

Conclusions:

In patients with postaxial hypoplasia, regular monitoring of the residual limb for growth-related changes must occur to ensure optimal function and prosthetic fit. Timing of the guided growth procedure is critical, as younger patients may be more likely to experience rebound deformity. Families and patients should be made aware that growth might be unpredictable in this population with risks of both overcorrection and undercorrection.

Level of Evidence:

Level IV—case series.
Does Shorter Time to Treatment of Pediatric Femur Shaft Fractures Impact Clinical Outcomes?
Authors: Grauberger Jennifer , O’Byrne Megan , Stans Anthony A. , Shaughnessy William J. , Larson A. Noelle , Milbrandt Todd A.
Published: March 2020

Background:

Annual rankings by US News and World Report are a widely utilized metric by both health care leaders and patients. One longstanding measure is time to treatment of femur shaft fractures. Hospitals able to provide at least 80% of pediatric patients with an operating room start time within 18 hours of admission to the emergency department score better as part of the overall pediatric orthopaedic ranking. Therefore, it is important to determine whether the 18-hour treatment time for pediatric femur shaft fractures is a clinically meaningful metric.

Methods:

A retrospective review of clinical outcomes of 174 pediatric patients (aged below 16 y) with isolated femur shaft fractures (Injury Severity Score=9) was conducted from 1997 to 2017 at a single level I pediatric trauma center. The 2 comparison groups were patients receiving fracture reduction within 18 hours of emergency department admission (N=87) or >18 hours (N=87).

Results:

Patient, injury, and surgical characteristics were similar between the 2 groups. Both groups had a similar mean age (treatment <18 h=7.5 y; treatment >18 h=8.1 y). Patients who received treatment within 18 hours were more often immobilized postoperatively (70.1% vs. 53.5%; P=0.0362) and had a shorter median hospital length of stay (2 vs. 3 d; P=0.0047). There were no statistically significant differences in any outcomes including surgical site infection, time to weight-bearing (treatment <18 h mean=48.1 d vs. 52.5 d), time to complete radiographic fracture healing (treatment <18 h mean=258.9 d vs. 232.0 d), decreased range of motion, genu varus/valgus, limb length discrepancy, loss of reduction, or persistent pain.

Conclusions:

Treatment of pediatric femur shaft fractures within 18 hours does not impact clinical outcomes. National quality measures should therefore use evidence-based metrics to help improve the standard of care.

Level of Evidence:

Therapeutic level III.
Tensioning Ligament and Tendon Repairs to Bone Using a Modified Screw-post Technique
Authors: Gordon Adam M. , Welder Eric , LoGiudice Tony , Goyal Kanu S.
Published: March 2020

Purpose:

The purpose of this study was to demonstrate how to tension tendon and ligament repairs or reconstructions to bone by using an oblique screw-post. A controlled experiment simulating this repair technique is reported, followed by 5 case examples.

Methods:

A wood frame model was used to test 5 initial exposed screw lengths (4, 8, 12, 16, 20 mm) and 5 screw angles [90 (perpendicular to wood plane), 75, 60, 45, 30 degrees]. A spring-based force gauge was tied to the exposed 3.5 mm cortical screw with a washer using a #2 nonabsorbable braided suture, and the screw was fully advanced. System lengths were measured before and after advancement using digital calipers. Screw angles were measured with a protractor. Analysis of variance with post hoc paired t tests was performed to compare changes in system length with different initial exposed screw length and screw angle.

Results:

Greater changes in system length was achieved with decreasing screw angle and increasing initial exposed length (P<0.05). A maximum change in system length of 12.4 mm (SD=0.4 mm) was achieved with a 45-degree screw with 20 mm initial exposed length (P<0.05). Five case examples where a screw-post was used to repair tendons and ligaments in the upper extremity are described.

Conclusions:

An oblique screw-post can advance a tendon or ligament repair to bone. This can result in increased tension of the repaired structure, potentially providing a better repair or greater joint stability.
A NOVEL APPROACH TO SCLERAL FIXATION OF POSTERIOR CHAMBER INTRAOCULAR LENSES AND CAPSULAR TENSION RINGS AND SEGMENTS IN DEEP-SET EYES
Authors: Miller Charles G. , Minkus Caroline , Lyon Alice T. , Basti Surendra , Leskov Ilya
Published: March 2020

Purpose:

To demonstrate a novel approach to scleral fixation of posterior chamber intraocular lenses and capsular tension rings and segments in deep-set eyes using the Finesse FlexLoop (Alcon Laboratories).

Methods:

The technique described herein, based on previous approaches to scleral fixation of posterior chamber intraocular lenses, uniquely employs the FlexLoop to “lasso” Gore-Tex sutures that have already been threaded through the eyelets of a CZ70BD (Alcon Laboratories) IOL and externalize them.

Results:

All patients who underwent surgery with this technique experienced visual improvement. The only complication was of mild hyphema in the patient who had a capsular tension segment placed, which resolved with medical therapy.

Conclusion:

The advantages of this procedure include a smaller diameter instrument (FlexLoop) as compared to the 25-gauge forceps typically employed, an easier to perform surgical maneuver that alleviates the need for both precise placement and constant tension to be exerted by the surgeon to grasp the sutures, as well as an instrument that can function when bent up to 45° to help accommodate deep-set eyes requiring this procedure.
Long-Term Refractive Outcome of Small Incision Lenticule Extraction in Very High Myopia
Authors: Elmassry Ahmed , Ibrahim Osama , Osman Ihab , Said Amr , Sabry Moataz , Seifelnasr Mohammed , Gaballah Karim , Abdalla Moones
Published: March 2020

Purpose:

To assess the stability, safety, predictability, and efficacy of small incision lenticule extraction (SMILE) in high myopia.

Methods:

The study was conducted as a retrospective noncomparative analysis of the records of 495 eyes of 270 patients treated by the ReLEx SMILE technique for a mean spherical myopic error of −12.84 ± 2.47 D (range: −10.0 to −14.0 D) combined with a mean astigmatism of −1.17 ± 1.34 D (up to −4.0 D). The mean LogMAR corrected distance visual acuity (CDVA) was 0.2 ± 0.6. In this study, 225 patients had the bilateral SMILE procedure, whereas 45 patients had a single eye treated with SMILE.

Results:

One month after surgery, the mean refractive error was 20.72 ± 0.88 D (range: +1 to 21.5 D), and the mean postoperative astigmatism was −0.83 ± 1.04 D. The mean LogMAR UDVA was 0.2 ± 0.34. In the last follow-up visit, 3 years after surgery, all the before mentioned parameters were the same or within minimal changes with no statistically significant difference from the earlier results. However, the spherical error demonstrated a significant change from −0.72 ± 0.88 D at 1 month to −1.17 ± 1.01 D at the end of the follow-up. However, this change had an insignificant visual impact. At the end of the follow-up period, approximately 94% of patients had unchanged CDVA or gained one or more lines, 6% lost one line of CDVA, and 1% lost 2 lines.

Conclusions:

SMILE may be effective and safe, with a stable and predictable outcome for correction of very high myopia.
Corneal Epithelial “Neuromas”: A Case of Mistaken Identity?
Authors: Stepp Mary Ann , Pal-Ghosh Sonali , Downie Laura E. , Zhang Alexis Ceecee , Chinnery Holly R. , Machet Joshua , Di Girolamo Nick
Published: March 2020

Laser scanning in vivo confocal microscopy is a useful clinical tool to assess the corneal nerves in human and laboratory animals. With this new technology, the use of terms such as “neuromas” and “microneuromas” is becoming popular to describe nerve structures seen in humans. Here, we point out that the sites where stromal nerves enter the corneal epithelium are often hyperreflective and can appear dysmorphic when imaged using in vivo confocal microscopy. Furthermore, we clarify what is known anatomically about how the nerves enter the corneal epithelium from the stroma, and we urge colleagues to differentiate between hyperreflective foci at the corneal stromal–epithelial nerve penetration sites and alterations in nerve morphology secondary to injury or disease.
Preloading Trifolded Grafts for Descemet Membrane Endothelial Keratoplasty Affects Scroll Formation
Authors: Solar Steven J. , Deljookorani Shiva , Wiener Batya G. , Rosen Allison , Chaurasia Akash , Shahmirzadi Monady , Meshkin Ryan S. , Dzhaber Daliya , Chiang Eric , Barnes Kali , Chen Conan Y. , Koo Ellen H. , Eghrari Allen O.
Published: March 2020

Purpose:

The trifolded, endothelium-in approach to Descemet membrane endothelial keratoplasty (DMEK) facilitates tissue insertion into the anterior chamber. We hypothesized that preloading the trifolded donor grafts in a cartridge for 48 hours before insertion would induce biomechanical changes that decrease their scrolling tendency compared with those loaded immediately before insertion.

Methods:

Ten Descemet membrane donor grafts, peeled and cut to 8.0 mm, were prepared by a single eye bank technician. Each graft was trifolded and pulled into a DMEK cartridge and stored for 48 hours. They were then pulled with microforceps into a petri dish filled with balanced salt solution. A video was recorded of the graft becoming a scroll over a 2-minute period. Each graft, serving as its own control, was then trifolded, pulled into the cartridge, and the process repeated. Images from 1, 5, 10, 60, and 120 seconds were extracted from video recording of the procedures. Scroll width was analyzed by graders masked to group assignment. A paired t test was used to determine differences in scroll width at each time point between the 48-hour and instant trifolding conditions.

Results:

All grafts scrolled after removal from the cartridge into balanced salt solution. We measured a significant difference at all time points 1 through 120 seconds (4.02 preloaded vs. 2.91-mm instant trifold, P = 0.035).

Conclusions:

Preloading DMEK grafts in a trifolded configuration for 48 hours reduces the scrolling tendency of Descemet membrane for at least 2 minutes.
Major Aspects of Burkholderia gladioli and Burkholderia cepacia Infections in Children
Authors: Bedir Demirdag Tugba , Ozkaya Parlakay Aslinur , Aygar Ismail Selcuk , Gulhan Belgin , Kanik Yuksek Saliha
Published: March 2020

Background:

Burkholderia cepacia complex is an aerobic, non–spore-forming, catalase-positive, nonfermentative, Gram-negative bacterium common in environment. It is a serious pathogen especially for patients with cystic fibrosis (CF). But pathogenicity of Burkholderia is not limited to patients with CF. Herein, we aimed to reveal clinical patterns and outcomes of Burkholderia infections in pediatric patients in our hospital and also antimicrobial susceptibility of the isolated strain.

Methods:

This retrospective study was conducted in Ankara Hematology Oncology Children’s Training and Research Hospital. Patients with isolates of Burkholderia spp. between January 6, 2013, and January 12, 2018, were included in the study.

Results:

Burkholderia spp. was isolated from 55 patients. 94.6% of these patients had underlying diseases and had prior hospitalization within a year. Burkholderia gladioli grew in 15 patients’ samples (27.3%); 38 patients grew B. cepacia (69.1%). None of the patients that B. gladioli was isolated was diagnosed as CF;. all had nosocomial infections. B. gladioli seemed to be more susceptible to aminoglycosides, piperacillin-tazobactam, carbapenems and ciprofloxacin than B. cepacia (P = 0.00), whereas B. cepacia seemed to be more susceptible to ceftazidime than B. gladioli (P = 0.032). In addition, B. cepacia was more susceptible to trimethoprim-sulfamethoxazole and levofloxacin than B. gladioli, but this difference was not statistically significant (P = 0.76).

Conclusions:

The incidence of nosocomial infections caused by Burkholderia spp. is rare especially in pediatric literature. In our study, nosocomial Burkholderia infections occurred mostly in intensive care unit patients. The surveillance of Burkholderia infections is still very important, and the clinicians should be aware of changing epidemiology and increasing resistance of the microorganism. Besides, there are no internationally agreed minimal inhibitory concentration breakpoints and disk-diffusion test thresholds for susceptibility testing for Burkholderia. Thus, the methods which were used for antibiotic susceptibility testing in our center might cause uncertainty about the results and internationally agreed minimal inhibitory concentration breakpoints and disk-diffusion test thresholds for susceptibility testing for Burkholderia is still a gap to fill for the current literature.
Mycoplasma pneumoniae in Children With and Without Community-acquired Pneumonia. What do PCR and Serology Say?
Authors: Copete Angela Rocio , Vera Cristian , Herrera Mariana , Aguilar Yudy Alexandra , Rueda Zulma Vanessa , Vélez Lázaro Agustín
Published: March 2020

Background:

IgM titers of Mycoplasma pneumoniae can remain high for months or years, and specific DNA can be detected in asymptomatic people.

Methods:

We compared the performance of serology and PCR in children with and without community-acquired pneumonia (CAP) for the diagnosis of M. pneumoniae.

Results:

In children with CAP, a positive test by M. pneumoniae (PCR and/or paired serology or both) were found in 13.9%. Of these, 10.3% were positive by multiplex PCR (Seeplex-Seegen), and 6.7% exhibited quadrupled titers (22 for IgG, 6 for IgM and 5 for both). Both tests were positive in 2.8% of cases. In the group without CAP, 3.3% were positive by PCR. Thirty-two percent of children with CAP and 38.3% of healthy children had IgM titers >11 in the acute phase.

Conclusions:

The detection of IgM is not useful for diagnosing acute M. pneumoniae infection, and a positive PCR result can be due to colonization and not infection. New and better diagnostic techniques are required.
Metastatic Squamous Cell Lung Carcinoma to the Optic Nerve Sheath Mimicking Retrobulbar Optic Neuritis
Authors: Shankar Vikram A. , Bialick Steven R. , Shafer Brian M.
Published: March 2020

Lung carcinoma is the second most common malignancy in both men and women, and may metastasize to the orbit relatively early in the disease course. Metastasis to the optic nerve or its sheath is an exceedingly rare occurrence, and diagnosis may be complicated by nonspecific clinical and radiographic features. The authors present a case of squamous cell lung cancer metastatic to the optic nerve sheath, initially diagnosed as optic neuritis based on its equivocal clinical and radiographic features. This is the first histopathologically confirmed case of squamous cell lung cancer metastatic to the optic nerve sheath in the literature.