bluuebunny/crossref_metadata_2025 huggingface dataset:
Trait‐mediated indirect interactions: Moose browsing increases sawfly fecundity through plant‐induced responses
Authors: Nordkvist Michelle , Klapwijk Maartje J. , Edenius Lars , Gershenzon Jonathan , Schmidt Axel , Björkman Christer
Published: August 2019

Induced responses in plants, initiated by herbivory, create potential for trait‐mediated indirect interactions among herbivores. Responses to an initial herbivore may change a number of plant traits that subsequently alter ecological processes with additional herbivores. Although common, indirect interactions between taxonomically distant herbivores, such as mammals and insects, are less studied than between taxonomically related species (i.e., insect–insect). In terms of mammal–insect interactions, effects on insect numbers (e.g., density) are relatively well studied, whereas effects on performance (e.g., fecundity) are rarely explored. Moreover, few studies have explored mammal–insect interactions on coniferous plants.

The aim of this study was to investigate the effect of mammalian induced responses on insect performance. We specifically investigated the effect of moose (Alces alces) browsing on Scots pine (Pinus sylvestris) and subsequent effects on sawfly (Neodiprion sertifer) performance.

Sawfly larvae were reared on browsed, clipped, and unbrowsed control pine trees in a controlled field experiment. Afterward, cocoon weight was measured. Needle C:N ratio and di‐terpene content were measured in response to browsing.

Sawfly performance was enhanced on trees browsed by moose. Cocoon weight (proxy for fecundity) was 9 and 13% higher on browsed and clipped trees compared to unbrowsed trees. Cocoon weight was weakly related to needle C:N ratio, and browsed trees had lower a C:N ratio compared to unbrowsed trees. Needle di‐terpene content, known to affect sawfly performance, was neither affected by the browsing treatments nor did it correlate with sawfly weight.

We conclude that mammalian herbivory can affect insect herbivore performance, with potential consequences for ecological communities and with particular importance for insect population dynamics. The measured plant variables could not fully explain the effect on sawfly performance providing a starting point for the consideration of additional plant responses induced by mammalian browsing affecting insect performance.
Sex differences in the genetic architecture of aggressiveness in a sexually dimorphic spider
Authors: Kralj‐Fišer Simona , Laskowski Kate L. , Garcia‐Gonzalez Francisco
Published: August 2019

Sex differences in the genetic architecture of behavioral traits can offer critical insight into the processes of sex‐specific selection and sexual conflict dynamics. Here, we assess genetic variances and cross‐sex genetic correlations of two personality traits, aggression and activity, in a sexually size‐dimorphic spider, Nuctenea umbratica. Using a quantitative genetic approach, we show that both traits are heritable. Males have higher heritability estimates for aggressiveness compared to females, whereas the coefficient of additive genetic variation and evolvability did not differ between the sexes. Furthermore, we found sex differences in the coefficient of residual variance in aggressiveness with females exhibiting higher estimates. In contrast, the quantitative genetic estimates for activity suggest no significant differentiation between males and females. We interpret these results with caution as the estimates of additive genetic variances may be inflated by nonadditive genetic effects. The mean cross‐sex genetic correlations for aggression and activity were 0.5 and 0.6, respectively. Nonetheless, credible intervals of both estimates were broad, implying high uncertainty for these estimates. Future work using larger sample sizes would be needed to draw firmer conclusions on how sexual selection shapes sex differences in the genetic architecture of behavioral traits.
Probing the Donor Properties of Pincer Ligands Using Rhodium Carbonyl Fragments: An Experimental and Computational Case Study
Authors: Parker Gemma L. , Lau Samantha , Leforestier Baptiste , Chaplin Adrian B.
Published: August 2019

Metal carbonyls are commonly employed probes for quantifying the donor properties of monodentate ligands. With a view to extending this methodology to mer‐tridentate “pincer” ligands, the spectroscopic properties [ν(CO), δ13C, 1JRhC] of rhodium(I) and rhodium(III) carbonyl complexes of the form [Rh(pincer)(CO)][BArF4] and [Rh(pincer)Cl2(CO)][BArF4] have been critically analysed for four pyridyl‐based pincer ligands, with two flanking oxazoline (NNN), phosphine (PNP), or N‐heterocyclic carbene (CNC) donors. Our investigations indicate that the carbonyl bands of the rhodium(I) complexes are the most diagnostic, with frequencies discernibly decreasing in the order NNN > PNP > CNC. To gain deeper insight, a DFT‐based energy decomposition analysis was performed and identified important bonding differences associated with the conformation of the pincer backbone, which clouds straightforward interpretation of the experimental IR data. A correlation between the difference in carbonyl stretching frequencies Δν(CO) and calculated thermodynamics of the RhI/RhIII redox pairs was identified and could prove to be a useful mechanistic tool.
Biomolecular Release Stimulated by Electrochemical Signals at a Very Small Potential Applied
Authors: Masi Madeline , Bollella Paolo , Katz Evgeny
Published: August 2019

DNA release electrochemically stimulated by applying −10 mV on the modified electrode was studied. The release process was based on the local (interfacial) pH change produced upon H2O2 reduction electrocatalyzed by the immobilized microperoxidase‐11. SiO2 nanoparticles attached to the electrode surface and functionalized with trigonelline and boronic acid species changed their electrical charge from positive to negative upon the interfacial pH change, thus allowing electrostatic adsorption of negatively charged DNA on the positive interface and then its repulsion/release from the negative interface. The loaded/released DNA molecules were labeled with a fluorescent dye to allow easy detection of the released DNA molecules. The important feature of the developed system is the controlled DNA release upon applying very small electrical potential on the modified electrode.
Investigation of Metal Ion Effect on Specific DNA Sequences and DNA Hybridization
Authors: Topkaya Seda Nur , Cetin Arif E.
Published: August 2019

In this article, we investigated the sequence specific interaction of single (ssDNA) and double stranded (dsDNA) with silver ions (Ag+) with electrochemical methods. We, for the first time, examined the effect of base sequences, base content and physiochemical properties of different DNA sequences on interaction with Ag+ in detail. We used different base contents to show how the composition of nucleic acid influences the electrochemical signals. We first immobilized ssDNA probes on bare graphite electrodes. Then, we showed the sequence effect on oxidation signals of AgDNA complex by sensing Ag+ to the probe coated surfaces to interact with different ssDNA sequences. Furthermore, we investigated the effect of Ag+ on dsDNA. We measured the oxidation signals obtained from Ag+‐ssDNA and Ag+‐dsDNA complex at approximately 0.2 V and 1.0 V (vs Ag/AgCl), respectively with Differential Pulse Voltammetry (DPV). We showed that the oxidation signals of the AgDNA complex obtained from dsDNA‐modified electrodes is higher than the electrodes modified with ssDNA. More importantly, we showed that Ag+‐ssDNA and Ag+ ion‐dsDNA exhibit different electrochemical behaviors.
Superior Cycling and Rate Performance of Micron‐Sized Tin Using Aqueous‐Based Binder as a Sustainable Anode for Lithium‐Ion Batteries
Authors: Ranjan Sahu Sumit , Rao Rikka Vallabha , Haridoss Prathap , Gopalan Raghavan , Prakash Raju
Published: August 2019

Recent developments in Sn‐based anodes for lithium‐ion batteries (LIBs) mostly rely on nanosized Sn particles with a conventional nonaqueous polyvinylidene fluoride binder, which is a major obstacle for the commercialization of Sn anodes due to the additional processing steps involved. Herein, the micron‐sized Sn (10 μm) is demonstrated as an anode material for LIBs using carbonyl‐β‐cyclodextrin as an environmentally benign and low cost aqueous binder. The optimized Sn electrode exhibits a remarkable reversible capacity of 577 mAh g−1 at 0.1 C rate between 3 and 0.05 V. A capacity of 256 and 117 mAh g−1 is obtained at 1 and 5 C, respectively, with a capacity retention of >80% after 1500 cycles. At 0.3 C lithiation rate, a delithiation capacity of 340 mAh g−1 is obtained at 5 C. The reversible capacities and cyclic stability further improve when the lithiation voltage is decreased to 0.025 V. The capacities at 0.1, 1, and 5 C are 723, 506, and 315 mAh g−1, respectively. A delithiation capacity of 478 mAh g−1 is obtained at 5 C at 0.3 C lithiation rate. It is believed that this method paves the way for using micron‐sized Sn as a sustainable anode material for LIBs.
Mitigation of voltage imbalance in power distribution system using MPC‐controlled packed‐U‐cells converter
Authors: Ahmed Ibrahim , Al‐Emadi Nasser , Gastli Adel , Ben‐Brahim Lazhar
Published: August 2019

Delivering high power quality in single‐phase distribution has witnessed more challenges especially with the increased penetration of single‐phase distributed generation (DG). This paper proposes a smart solid‐state‐based transformer, which aims to replace traditional ones, for single‐phase distribution laterals, and provide load balancing and protection to the three‐phase main feeders, that is based on connecting the single‐phase lateral to the three‐phase main feeder through a power electronics converter. This converter transfers balanced power from and to the three‐phase feeder while automatically regulating the lateral single‐phase voltage, hence, assuring high power quality without requiring any transformer on‐load tap changer. A 7‐level packed‐U‐cells (PUC) single‐phase inverter topology was used to deliver single‐phase regulated sinusoidal voltage to the AC loads, and at the same time, it is able to deliver DC power to DC loads. The simulation and hardware‐in‐the‐loop (HIL) results have shown that the proposed topology delivers high power quality for both AC and DC loads under different operating scenarios. Moreover, the converter can play the role of a solid‐state protection device coordinated with other up‐ and downstream protective devices. Finally, this system can be integrated within the smart grid allowing more flexibility for automation and efficient control of the grid.
Analysis of brain subnetworks within the context of their whole‐brain networks
Authors: Bahrami Mohsen , Laurienti Paul J. , Simpson Sean L.
Published: August 2019

Analyzing the structure and function of the brain from a network perspective has increased considerably over the past two decades, with regional subnetwork analyses becoming prominent in the recent literature. However, despite the fact that the brain, as a complex system of interacting subsystems (i.e., subnetworks), cannot be fully understood by analyzing its constituent parts as independent elements, most studies extract subnetworks from the whole and treat them as independent networks. This approach entails neglecting their interactions with other brain regions and precludes identifying potential compensatory mechanisms outside the analyzed subnetwork. In this study, using simulated and empirical data, we show that the analysis of brain subnetworks within the context of their whole‐brain networks, that is, including their interactions with other brain regions, can yield different outcomes when compared to analyzing them as independent networks. We also provide a multivariate mixed‐effects modeling framework that allows analyzing subnetworks within the context of their whole‐brain networks, and show that it can better disentangle global (whole‐brain) and local (subnetwork) differences when compared to standard t‐test analyses. T‐test analyses may produce misleading results in identifying complex global and local level differences. The provided multivariate model is an extension of a previously developed model for global, system‐level hypotheses about the brain. The modified version detailed here provides the same utilities as the original model—quantifying the relationship between phenotypes and brain connectivity, comparing brain networks among groups, predicting brain connectivity from phenotypes, and simulating brain networks—but for local, subnetwork‐level hypotheses.
Rotavirus Reassortant–Induced Murine Model of Liver Fibrosis Parallels Human Biliary Atresia
Authors: Mohanty Sujit K. , Lobeck Inna , Donnelly Bryan , Dupree Phylicia , Walther Ashley , Mowery Sarah , Coots Abigail , Bondoc Alexander , Sheridan Rachel M. , Poling Holly M. , Temple Haley , McNeal Monica , Sestak Karol , Bansal Ruchi , Tiao Greg
Published: August 2019

Background and Aims

Biliary atresia (BA) is a devastating neonatal cholangiopathy that progresses to fibrosis and end‐stage liver disease by 2 years of age. Portoenterostomy may reestablish biliary drainage, but, despite drainage, virtually all afflicted patients develop fibrosis and progress to end‐stage liver disease requiring liver transplantation for survival.

Approach and Results

In the murine model of BA, rhesus rotavirus (RRV) infection of newborn pups results in a cholangiopathy paralleling human BA and has been used to study mechanistic aspects of the disease. Unfortunately, nearly all RRV‐infected pups succumb by day of life 14. Thus, in this study we generated an RRV‐TUCH rotavirus reassortant (designated as TR(VP2,VP4)) that when injected into newborn mice causes an obstructive jaundice phenotype with lower mortality rates. Of the mice that survived, 63% developed Ishak stage 3‐5 fibrosis with histopathological signs of inflammation/fibrosis and bile duct obstruction.

Conclusions

This model of rotavirus‐induced neonatal fibrosis will provide an opportunity to study disease pathogenesis and has potential to be used in preclinical studies with an objective to identify therapeutic targets that may alter the course of BA.
TMZ regulates GBM stemness via MMP14‐DLL4‐Notch3 pathway
Authors: Ulasov Ilya V. , Mijanovic Olja , Savchuk Solomiia , Gonzalez‐Buendia Edgar , Sonabend Adam , Xiao Ting , Timashev Petr , Lesniak Maciej S.
Published: August 2019

Glioblastoma (GBM) is one of the most aggressive primary brain tumors with frequent recurrences following the standard methods of treatment—temozolomide (TMZ), ionizing radiation and surgical resection. The objective of our study was to investigate GBM resistance mediated via MMP14 (matrix metalloproteinase 14). We used multiple PDX GBM models and established glioma cell lines to characterize expression and subcellular localization of MMP14 after TMZ treatment. We performed a Kiloplex ELISA‐based array to evaluate changes in cellular proteins induced by MMP14 expression and translocation. Lastly, we conducted functional and mechanistic studies to elucidate the role of DLL4 (delta‐like canonical notch ligand 4) in regulation of glioma stemness, particularly in the context of its relationship to MMP14. We detected that TMZ treatment promotes nuclear translocation of MMP14 followed by extracellular release of DLL4. DLL4 in turn stimulates cleavage of Notch3, its nuclear translocation and induction of sphering capacity and stemness.
Impact of language on behavior treatment outcomes
Authors: Neely Leslie , Graber Jessica , Kunnavatana Shanun , Cantrell Katherine
Published: August 2019

Resurgence of problem behavior following effective functional communication training (FCT) can occur if the functional communication response contacts extinction. For children from dual‐language households, extinction may unintentionally occur due to language variations among communication partners. In the current study, the experimenters evaluated the effect of language on FCT outcomes. Participants were 3 children with autism who engaged in problem behavior and whose parents reported Spanish as the primary home language. The experimenters conducted FCT in the English language followed by probes in the Spanish language. Results suggest that functional communication responses (FCRs) learned in the first language (English) may lead to resurgence of problem behavior when English FCRs do not contact reinforcement in the untaught language (e.g., Spanish). Two of the participants required additional teaching in the secondary language (Spanish), while the third participant eventually emitted Spanish FCRs in the Spanish condition without explicit teaching.
Physical nature of silane⋯carbene dimers revealed by state‐of‐the‐art ab initio calculations
Authors: Yourdkhani Sirous , Jabłoński Mirosław
Published: August 2019

Using the SAPT2 + 3(CCD)δMP2 method in complete basis set (CBS) limit, it is shown that the interactions in the recently studied silane⋯carbene dimers are mainly dispersive in nature. Consequently, slow convergence of dispersion energy also forces slow convergence of the interaction energy. Therefore, obtaining very accurate values requires extrapolation of the correlation part to the CBS limit. The most accurate values obtained at the CCSD(T)/CBS level of theory show that the studied silane⋯carbene dimers are rather weakly bound, with interaction energies ranging from about −1.9 to −1.3 kcal/mol. Comparing to CCSD(T)/CBS, it will be shown that SCS‐MP2 and MP2C methods clearly underestimate and methods based on SAPT2+ and having some third‐order corrections, as well as the MP2 method, overestimate values of interaction energies. Popular SAPT(DFT) method performs better than SCS‐MP2 and MP2C; nevertheless, underestimation is still considerable. The underestimation is slightly quenched if third‐order dispersion energy and its exchange counterpart is added to the SAPT(DFT). The closest value of CCSD(T)/CBS has been given by the SAPT2 + (3)(CCD)δMP2 method in quadruple‐ζ basis set. © 2019 Wiley Periodicals, Inc.
Characterization of LDLR rs5925 and PCSK9 rs505151 genetic variants frequencies in healthy subjects from northern Chile: Influence on plasma lipid levels
Authors: Rojas Claudio , Ramírez Hugo , Salazar Luis A. , Kalergis Alexis M. , Gálvez Anita S. , Escobar‐Vera Jorge
Published: August 2019

Background

Identification and characterization of genetic variants and their effects on human health may allow to establish relationships between genetic background and susceptibility to developing cardiovascular diseases. LDLR and PCSK9 polymorphisms have been associated with higher lipid levels and risk of cardiovascular diseases. Thus, the main aim of this study was to evaluate genotype distribution and relative allelic frequency of LDLR rs5925 (1959C > T) and PCSK9 rs505151 (23968 A > G) genetic variants and their effects on lipid levels of healthy subjects from northern Chile.

Methods

A total of 178 healthy individuals were recruited for this study. The genotyping of rs5925 (LDLR) and rs505151 (PCSK9) polymorphisms was performed by PCR‐RFLP and qPCR, respectively. In addition, glucose and lipid levels were determined and associated with the genetic data.

Results

Genotype distribution for LDLR rs5925 polymorphism was as follows: CC = 19%; CT = 53%; and TT = 28% (HWE: χ2 = 0.80; P = .37), and for PCSK9 rs505151 genetic variant was as follows: AA = 93%; AG = 7%; and GG = 0% (HWE: χ2 = 0.22; P = .64). The frequency of T (rs5925) and G (rs505151) mutated alleles was 0.55 and 0.03, respectively. Data showed that individuals carrying LDLR mutated allele (T) presented lower values of total cholesterol, triglycerides, and LDL‐cholesterol when compared to CC homozygous genotype (P < .05). Subgroup analysis revealed that women carrying the PCSK9 mutated allele (G) exhibited higher values of total cholesterol, triglycerides, HDL‐C, and LDL‐C when compared to male group carrying the same genotype (P < .05).

Conclusions

The effect of LDLR rs5925 and PCSK9 rs505151 gene polymorphisms on lipid levels is associated with gender among healthy subjects from northern Chile.
Nanoparticles and cancer therapy: Perspectives for application of nanoparticles in the treatment of cancers
Authors: Aghebati‐Maleki Ali , Dolati Sanam , Ahmadi Majid , Baghbanzhadeh Amir , Asadi Milad , Fotouhi Ali , Yousefi Mehdi , Aghebati‐Maleki Leili
Published: August 2019

Rapid growth in nanotechnology toward the development of nanomedicine agents holds massive promise to improve therapeutic approaches against cancer. Nanomedicine products represent an opportunity to achieve sophisticated targeting strategies and multifunctionality. Nowadays, nanoparticles (NPs) have multiple applications in different branches of science. In recent years, NPs have repetitively been reported to play a significant role in modern medicine. They have been analyzed for different clinical applications, such as drug carriers, gene delivery to tumors, and contrast agents in imaging. A wide range of nanomaterials based on organic, inorganic, lipid, or glycan compounds, as well as on synthetic polymers has been utilized for the development and improvement of new cancer therapeutics. In this study, we discuss the role of NPs in treating cancer among different drug delivery methods for cancer therapy.
Diagnostic accuracy of ultrasound‐guided core biopsy of peripheral nerve sheath tumors
Authors: Tøttrup Mikkel , Eriksen Jacob D. , Hellfritzsch Michel B. , Sørensen Flemming B. , Baad‐Hansen Thomas
Published: August 2019

Purpose

To retrospectively evaluate the diagnostic accuracy of and complications from ultrasound‐guided core needle biopsy (UGCNB) of suspected peripheral nerve sheath tumors (PNSTs).

Methods

Patients undergoing UGCNB from January 2004 to December 2016, based on the suspicion of PNST, were included in the study. Age, gender, anatomical location, dates of relevant events, and histopathological reports of the UGCNB cores and the resected tumors were retrieved from the patients' medical records.

Results

A total of 154 UGCNBs were identified. One hundred and forty (90.9%) of these resulted in a conclusive histopathological report, while 14 were unsuited for histopathological analysis due to insufficient amount of tissue and/or nonrepresentative tissue. The overall diagnostic accuracy of UGCNB with respect to discriminate malignant from benign tumors was 99.3%, while correct specific UGCNB diagnoses were confirmed in 95.1% of the cases. Sensitivity and specificity were 90.9% (95% CI: 58.7‐99.8%) and 100% (95% CI: 97.2‐100%), respectively. The positive predictive value was 100%, and the negative predictive value was 99.2%. Except for one patient, who reported mild dysesthesia, which resolved 2 days after the UGCNB, no complications were reported.

Conclusion

This study suggests that UGCNB is accurate and safe in patients suspected for PNST.
Point‐of‐care viral load monitoring: outcomes from a decentralized HIV programme in Malawi
Authors: Nicholas Sarala , Poulet Elisabeth , Wolters Liselotte , Wapling Johanna , Rakesh Ankur , Amoros Isabel , Szumilin Elisabeth , Gueguen Monique , Schramm Birgit
Published: August 2019

Introduction

Routinely monitoring the HIV viral load (VL) of people living with HIV (PLHIV) on anti‐retroviral therapy (ART) facilitates intensive adherence counselling and faster ART regimen switch when treatment failure is indicated. Yet standard VL‐testing in centralized laboratories can be time‐intensive and logistically difficult in low‐resource settings. This paper evaluates the outcomes of the first four years of routine VL‐monitoring using Point‐of‐Care technology, implemented by Médecins Sans Frontières (MSF) in rural clinics in Malawi.

Methods

We conducted a retrospective cohort analysis of patients eligible for routine VL‐ testing between 2013 and 2017 in four decentralized ART‐clinics and the district hospital in Chiradzulu, Malawi. We assessed VL‐testing coverage and the treatment failure cascade (from suspected failure (first VL>1000 copies/mL) to VL suppression post regimen switch). We used descriptive statistics and multivariate logistic regression to assess factors associated with suspected failure.

Results and Discussion

Among 21,400 eligible patients, VL‐testing coverage was 85% and VL suppression was found in 89% of those tested. In the decentralized clinics, 88% of test results were reviewed on the same day as blood collection, whereas in the district hospital the median turnaround‐time for results was 85 days. Among first‐line ART patients with suspected failure (N = 1544), 30% suppressed (VL<1000 copies/mL), 35% were treatment failures (confirmed by subsequent VL‐testing) and 35% had incomplete VL follow‐up. Among treatment failures, 80% (N = 540) were switched to a second‐line regimen, with a higher switching rate in the decentralized clinics than in the district hospital (86% vs. 67%, p < 0.01) and a shorter median time‐to‐switch (6.8 months vs. 9.7 months, p < 0.01). Similarly, the post‐switch VL‐testing rate was markedly higher in the decentralized clinics (61% vs. 26%, p < 0.01). Overall, 79% of patients with a post‐switch VL‐test were suppressed.

Conclusions

Viral load testing at the point‐of‐care in Chiradzulu, Malawi achieved high coverage and good drug regimen switch rates among those identified as treatment failures. In decentralized clinics, same‐day test results and shorter time‐to‐switch illustrated the game‐changing potential of POC‐based VL‐testing. Nevertheless, gaps were identified along all steps of the failure cascade. Regular staff training, continuous monitoring and creating demand are essential to the success of routine VL‐testing.
Lose‐Dose Administration of Dexamethasone Is Beneficial in Preventing Secondary Tendon Damage in a Stress‐Deprived Joint Injury Explant Model
Authors: Connizzo Brianne K. , Grodzinsky Alan J.
Published: August 2019

Secondary joint damage is the process by which a single injury can lead to detrimental changes in adjacent tissue structures, typically through the spread of inflammatory responses. We recently developed an in vitro model of secondary joint damage using a murine rotator cuff explant system, in which injuries to muscle and bone cause massive cell death in otherwise uninjured tendon. The purpose of the present study was to test the ability cytokine‐targeted and broad‐spectrum therapeutics to prevent cell death and tissue degeneration associated with secondary joint damage. We treated injured bone‐tendon‐muscle explants with either interleukin‐1 receptor antagonist, etanercept, or dexamethasone (DEX) for up to 7 days in culture. Only the low‐dose DEX treatment was able to prevent cell death and tissue degeneration. We then identified a critical window between 24 and 72 h following injury for maximal benefit of DEX treatment through timed administration experiments. Finally, we performed two tendon‐only explant studies to identify mechanistic effects on tendon health. Interestingly, DEX did not prevent cell death and degeneration in a model of cytokine‐induced damage, suggesting other targets of DEX activity. Future studies will aim to identify factors in joint inflammation that may be targeted by DEX treatment, as well as to investigate novel delivery strategies. Statement of clinical significance: Overall, this work demonstrates beneficial effects of DEX administration on preventing tenocyte death and extracellular matrix degeneration in an explant model of secondary joint damage, supporting the clinical use of low‐dose glucocorticoids for short‐term treatment of joint inflammation. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 38:139–149, 2020
Is a Local Administration of Parathyroid Hormone Effective to Tendon‐to‐Bone Healing in a Rat Rotator Cuff Repair Model?
Authors: Yoon Jong Pil , Chung Seok Won , Jung Jae Wook , Lee Yong‐Soo , Kim Kwang‐Il , Park Ga Young , Kim Hun‐Min , Choi Jin‐Hyun
Published: August 2019

To evaluate the effect of local parathyroid hormone (PTH) administration on rotator cuff tendon‐to‐bone healing in a rat model compared with systemic PTH injection and untreated controls. PTH‐alginate scaffold was prepared and sustained release of PTH was confirmed. Bilateral supraspinatus tendon repairs were performed in 39 rats (group 1, supraspinatus repair only; group 2, supraspinatus repair with systemic PTH injection; group 3, supraspinatus repair with local PTH administration via an absorbable scaffold; n = 13 each). Biomechanical (cross‐sectional area, mode of failure, load to failure, and ultimate stress: right side) and histological analyses (hematoxylin and eosin stain, Masson's Trichrome stain Picrosirius red stain, Immunohistochemistry for BMP2, PTH1R, ColI, and ColIII: Left side) were performed to evaluate tendon‐to‐bone healing quality at 8 weeks after repair, and blood test (osteocalcin and procollagen type I N‐terminal pro‐peptide [PINP] levels) was performed in all rats. There was no intergroup difference in the healing failure rate (p = 0.910) or failure mode (p = 0.585). Biomechanically, subjects in groups 2 and 3 exhibited significantly larger cross‐sectional areas and higher ultimate failure loads and ultimate stress than those in group 1 (all p < 0.05); however, no differences were noted between groups 2 and 3 (all p > 0.05). Histologically, groups 2 and 3 exhibited more organized tendon‐to‐bone interface structures with higher density, parallel orientation, and collagen fiber continuity than group 1 (all p < 0.05 except collagen fiber continuity in group 1 vs. 2); however, no differences in histological parameters between groups 2 and 3 (all p > 0.05). The protein levels of bone morphogenic protein 2, PTH 1 receptor, and collagen I and III and the serum level of PINP were increased in groups 2 and 3 versus group 1 (all p < 0.05) without showing differences between groups 2 and 3 (all p > 0.05). Local PTH administration using an absorbable scaffold improved the biomechanical and histological outcomes of rotator cuff tendon‐to‐bone healing comparable with systemic PTH injection at 8 weeks after repair in a rat model. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 38:82–91, 2020
In‐Room Ultraviolet Air Filtration Units Reduce Airborne Particles During Total Joint Arthroplasty
Authors: Anis Hiba K. , Curtis Gannon L. , Klika Alison K. , Piuzzi Nicolas S. , Otiso Joshua , Richter Sandra S. , Barsoum Wael K. , Higuera Carlos A.
Published: August 2019

Reducing airborne bioburden in total joint arthroplasty (TJA) is of critical importance. The efficacy of crystalline ultraviolet‐C (C‐UVC) filtration in reducing bioburden in a dynamic operating room (OR) environment has not been evaluated. We assessed whether C‐UVC filtration reduced (i) total particle counts (TPC); (ii) viable particle counts (VPC); and (iii) colony‐forming units (CFUs). Fifty primary TJA cases were performed in a positive‐pressure OR; 25 cases with the C‐UVC unit and 25 cases without. The air was sampled by a particle counter and an impact air sampler to measure particle counts and CFUs, respectively. To compare TPC, VPC, and CFU/m3 between groups, independent t tests and multivariate regression, adjusted for number of OR staff and door openings, were performed. The C‐UVC group had significantly lower TPC (2.6 × 106 vs. 4.7 × 106 particles, p = 0.001) and VPC (18,605 vs. 27,516 particles, p = 0.001). There were fewer CFUs in the C‐UVC group (10.9 CFU/m3 vs. 13.7 CFU/m3, p = 0.163). Multivariate analysis identified C‐UVC filtration as a significant predictor of decreased TPC (β = −0.44, p = 0.002) and VPC (β = −0.47, p = 0.001) after accounting for door openings and number of OR staff. The reduction in CFUs was not significant on multivariate analysis. In this prospective pilot study, a C‐UVC air disinfection and recirculation unit led to a significant reduction in both TPC and VPC and a non‐significant reduction in CFU. Statement of clinical significance: Further studies are needed to investigate the effects of C‐UVC filtration units on surgical‐site infection rates. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 38:431‐437, 2020
Effects of T‐2 toxin on the muscle proteins of shrimp (Litopenaeus vannamei) – a proteomics study
Authors: Huang Zhanrui , Wang Yaling , Sun Lijun , Wang Xiaobo , Lu Pengli , Liang Guangming , Pang Huanying , Wu Qinghua , Gooneratne Ravi , Zhao Jian
Published: August 2019

BACKGROUND

T‐2 toxin (T‐2) is a potent mycotoxin and a common contaminant of aquatic animal feed, posing a serious risk to health and aquatic animals. We investigated the effect of T‐2 on shrimp muscle proteins using proteomics and conventional biochemical methods. Shrimp were fed a diet containing T‐2 at 0–12.2 mg kg−1 for 20 days, and changes to the muscle protein composition, ATPase activities, and the sulfhydryl (SH) content and hydrophobicity of actomyosin (AM) were determined. A proteomics study of the proteins was conducted with sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS‐PAGE), two‐dimensional (2D) electrophoresis, and matrix‐assisted laser desorption/ionization – time of flight mass spectrometry (MALDI‐TOF/TOF MS).

RESULTS

Exposure to T‐2 markedly affected the muscle protein composition of shrimp in a concentration‐responsive manner that displayed a diphasic effect. At a low T‐2 concentration (1.2 mg kg−1), the levels of three major muscle proteins (myofibrillar, sarcoplasmic, and stroma) increased but at higher concentrations they declined progressively. T‐2 exposure also led to a breakdown of muscle proteins as evidenced by increases in alkali‐soluble protein and the surface hydrophobicity (SoANS) of AM. Thirty differentially expressed proteins were detected, 12 of which showed a concentration‐response relationship with T‐2 exposure. Among them, 11 homologous proteins were identified by mass spectrometry (MS), with several being key enzymes in energy metabolism.

CONCLUSION

This study demonstrated that T‐2 exposure at medium to high concentrations could significantly affect the protein composition and quality of shrimp muscle, and potentially some of its key metabolisms. One of the arginine kinases (spot 27) was particularly responsive to T‐2 and could potentially be used as a biomarker protein for T‐2 intoxication by shrimp. © 2019 Society of Chemical Industry
Analysis of reciprocating O‐ring seal in the pressure‐balanced oil‐filled wet‐mate electrical connectors for underwater applications
Authors: Han Quan , Chen Haiyang , Yang Wencong , Zhang Yan , Yang Juekuan , Chen Yunfei
Published: August 2019

The rapidly growing demand for wet‐mate electrical connectors in underwater projects has attracted the attention of researchers in the field. Sealing is the key to underwater connectors. In this paper, the reciprocating O‐ring seal during underwater operations of the pressure‐balanced connectors was studied. A numerical model containing the Reynolds equation, hyperelastic deformation, and asperity contact was used to describe mixed elastohydrodynamic lubrication (EHL) in the O‐ring seal. Results indicate that the friction force of the seal in the connector decreases directly with the increased sealed pressure, and its friction force is smaller than that in the conventionally hydraulic structure. As the sealed pressure increases, the minimum film thickness in the connector increases, which means a better lubrication in the deeper sea. The oil leakage in the connector increases with the sealed pressure, but the increase rate is smaller than that in the hydraulic structure. It proves that the design of pressure‐balanced structure can not only achieve wet‐mate operation at any depth but also facilitate its dynamic sealing performance.
Laser‐Assisted Control of Epistaxis in Hereditary Hemorrhagic Telangiectasia: A Systematic Review
Authors: Abiri Arash , Goshtasbi Khodayar , Maducdoc Marlon , Sahyouni Ronald , Wang Marilene B. , Kuan Edward C.
Published: August 2019

Background and Objectives

Hereditary hemorrhagic telangiectasia (HHT), also known as Osler–Weber–Rendu disease, causes recurrent mucous membrane hemorrhage, especially epistaxis. In this systematic review, we discuss the efficacies of the three most common laser photocoagulation treatments for HHT‐related epistaxis.

Study Design/Materials and Methods

A systematic literature search was conducted in PubMed and MEDLINE from database inception to March 2019. Studies reporting epistaxis outcomes following argon, neodymium‐doped yttrium aluminum garnet (Nd:YAG), and diode laser photocoagulation for HHT were included. χ2 and Barnard's exact tests were utilized to detect differences in reduced epistaxis frequency and intensity rates.

Results

Fifteen out of 157 published studies met our eligibility criteria, spanning a collective 362 patients. Argon, Nd:YAG, and diode laser therapy reduced epistaxis frequency in 90.4%, 88.9%, and 71.1% of patients, respectively, and reduced epistaxis intensity in 87.8%, 87.2%, and 71.1% of patients, respectively. Diode laser photocoagulation significantly underperformed in both outcome measurements when compared with argon (frequency: P = 0.005; intensity: P = 0.034) and Nd:YAG (frequency: P = 0.012; intensity: P = 0.041). There was no significant difference between argon and Nd:YAG in reducing HHT epistaxis frequency (P = 0.434) or intensity (P = 0.969). Categorizing HHT patients by clinical severity demonstrated a higher rate of improvement in the mild‐moderate group compared with the severe group in both argon (P < 0.001) and Nd:YAG (P < 0.001) therapeutic methods. While no significant differences were found in rates of improved epistaxis outcomes between argon and Nd:YAG in mild‐moderate HHT patients (frequency: P = 0.061; intensity: P = 0.061), Nd:YAG demonstrated greater rates of reduction in epistaxis frequency (P = 0.040) and intensity (P = 0.028) than argon among severe HHT patients.

Conclusions

HHT is a lifelong disease, plaguing patients with debilitating epistaxis. Intranasal laser photocoagulation of telangiectasias using argon or Nd:YAG laser therapy can yield improved epistaxis outcomes compared with diode laser photocoagulation. In severe cases of HHT, Nd:YAG laser therapy provides greater improvements in epistaxis outcomes than argon photocoagulation. Lasers Surg. Med. © 2019 Wiley Periodicals, Inc.
The Aluthge transform of unilateral weighted shifts and the Square Root Problem for finitely atomic measures
Authors: Curto Raúl E. , Kim Jaewoong , Yoon Jasang
Published: August 2019

In this paper we consider the following Square Root Problem for measures: Given a positive probability Borel measure μ (supported on an interval ), does there exist a positive Borel measure ν such that holds? (Here * denotes the multiplicative convolution, properly defined on .) This problem is intimately connected to the subnormality of the Aluthge transform of a unilateral weighted shift. We develop a criterion to test whether a measure μ admits a square root, and we provide a concrete solution for the case of a finitely atomic measure having at most five atoms. In addition, we sharpen the statement of a previous result on this topic and extend its applicability via a new technique that uses the standard inequality of real numbers to generate a diagram of a partial order on the support of a probability measure.
Deformation behavior and constitutive model for high temperature compression of a newly type of Ni3Al‐based superalloy
Authors: Zhong J. , Xu Z. , Liu B. , Xu Q. , Sun C. , Wu J.
Published: August 2019

In order to investigate the hot deformation mechanism of a newly development Ni3Al‐based superalloy, hot compression tests at temperatures between 1100 °C–1250 °C and the strain rates of 0.001 s−1–1.0 s−1 were conducted. The results show that the curves of true stress‐strain indicate the thermal deformation is a typical dynamic recrystallization process, which the peak stresses and steady‐state stresses increase with decreasing temperatures and increasing strain rates. The softening mechanism is mainly dynamic recrystallization. The experimental data of peak stresses and steady‐state stresses is employed to calculate the constants in the Arrhenius equation. The steady‐state stresses are considered more reasonable for solving the parameters in the Arrhenius equation. Based on the constitutive equation obtained, the calculated values of steady‐state stresses match well with the experimental values at the strain rates of 0.001 s−1, 0.01 s−1 and 0.1 s−1, whereas there exists much deviation at 1.0 s−1. For the sake of accuracy of predicted results at 1.0 s−1 strain rate, a modified Zener‐Hollomon parameter Z’ is introduced. The results show that the modified constitutive equations established in this study could well predict the value of steady‐state stress in hot deformation of the newly development Ni3Al‐based alloy.
NifA is the master regulator of both nitrogenase systems in Rhodobacter capsulatus
Authors: Demtröder Lisa , Pfänder Yvonne , Schäkermann Sina , Bandow Julia Elisabeth , Masepohl Bernd
Published: August 2019

Rhodobacter capsulatus fixes atmospheric nitrogen (N2) by a molybdenum (Mo)‐nitrogenase and a Mo‐free iron (Fe)‐nitrogenase, whose production is induced or repressed by Mo, respectively. At low nanomolar Mo concentrations, both isoenzymes are synthesized and contribute to nitrogen fixation. Here we examined the regulatory interplay of the central transcriptional activators NifA and AnfA by proteome profiling. As expected from earlier studies, synthesis of the structural proteins of Mo‐nitrogenase (NifHDK) and Fe‐nitrogenase (AnfHDGK) required NifA and AnfA, respectively, both of which depend on the alternative sigma factor RpoN to activate expression of their target genes. Unexpectedly, NifA was found to be essential for the synthesis of Fe‐nitrogenase, electron supply to both nitrogenases, biosynthesis of their cofactors, and production of RpoN. Apparently, RpoN is the only NifA‐dependent factor required for target gene activation by AnfA, since plasmid‐borne rpoN restored anfH transcription in a NifA‐deficient strain. However, plasmid‐borne rpoN did not restore Fe‐nitrogenase activity in this strain. Taken together, NifA requirement for synthesis and activity of both nitrogenases suggests that Fe‐nitrogenase functions as a complementary nitrogenase rather than an alternative isoenzyme in R. capsulatus.
Withaferin A inhibits expression of ataxia telangiectasia and Rad3‐related kinase and enhances sensitivity of human breast cancer cells to cisplatin
Authors: Hahm Eun‐Ryeong , Lee Joomin , Abella Terric , Singh Shivendra V.
Published: August 2019

Ataxia telangiectasia and Rad3‐related (ATR) is a serine/threonine‐specific kinase that plays an important role in the maintenance of genomic integrity. In this study, we investigated the role of ATR in cell‐cycle arrest by withaferin A (WA), a cancer preventative steroidal lactone derived from Withania somnifera plant abundant in India and surrounding countries. The WA treatment decreased the viability of MCF‐7, MDA‐MB‐231, and SUM159 cells. Exposure of breast cancer cells to WA also resulted in suppression of protein level as well as phosphorylation of ATR and its downstream effector kinase (checkpoint kinase 1; CHK1). Both transcriptional and posttranscriptional mechanisms were involved in the WA‐mediated downregulation of ATR protein. Downregulation of ATR protein expression resulting from WA exposure was not attenuated by overexpression of manganese superoxide dismutase. In contrast, the overexpression of CHK1 attenuated WA‐mediated G2/M arrest and augmented S10 phosphorylation of histone H3, a marker of mitotic arrest. The protein level of ATR was lowered by about 50% in breast tumors of WA‐treated mouse mammary tumor virus‐neu mice when compared with vehicle‐treated controls but the difference was not significant due to small sample size. WA treatment sensitized MDA‐MB‐231 and SUM159 cells to growth inhibition and apoptosis induction by cisplatin. Cisplatin treatment resulted in increased autophosphorylation of ATR (T1989) and CHK1 (S345) phosphorylation that was markedly suppressed in the presence of WA. These results indicate that WA is an inhibitor of ATR in human breast cancer cells.
Retracted: MiR‐497‐5p inhibits cell proliferation and metastasis in hepatocellular carcinoma by targeting insulin‐like growth factor 1
Authors: Xu Guo‐shu , Li Zi‐wei , Huang Zhi‐Ping , Brunicardi F. Charles , Jia Fu , Song Chao , Zou Hai‐jian , Sun Rui‐fen
Published: August 2019

Background

MicroRNAs (miRNAs) play an important regulatory role in carcinogenesis and cancer progression. Aberrant expression of miR‐497‐5p has been reported in various human malignancies. However, the role of miR‐497‐5p in hepatocellular carcinoma (HCC) remains unclear.

Results

In this study, we found that miR‐497‐5p was downregulated in HCC tissues. The low level of miR‐497‐5p in HCC tumors was correlated with aggressive clinicopathological characteristics and predicted poor prognosis in HCC patients. The overexpression of miR‐497‐5p significantly inhibited HCC cell proliferation, colony formation, and metastasis in vitro and vivo. Bioinformatics analysis further identified insulin‐like growth factor 1 (IGF1) as a novel target of miR‐497‐5p in HCC cells.

Conclusion

Our study suggested that miR‐497‐5p regulates HCC cell survival, partially through downregulation of IGF1. Therefore, the miR‐497‐5p/IGF1 axis might serve as a novel therapeutic target in patients with HCC.
Organ doses from CT localizer radiographs: Development, validation, and application of a Monte Carlo estimation technique
Authors: Hoye Jocelyn , Sharma Shobhit , Zhang Yakun , Fu Wanyi , Ria Francesco , Kapadia Anuj , Segars W. Paul , Wilson Joshua , Samei Ehsan
Published: August 2019

Purpose

The purpose of this study was to simulate and validate organ doses from different computed tomography (CT) localizer radiograph geometries using Monte Carlo methods for a population of patients.

Methods

A Monte Carlo method was developed to estimate organ doses from CT localizer radiographs using PENELOPE. The method was validated by comparing dosimetry estimates with measurements using an anthropomorphic phantom imbedded with thermoluminescent dosimeters (TLDs) scanned on a commercial CT system (Siemens SOMATOM Flash). The Monte Carlo simulation platform was then applied to conduct a population study with 57 adult computational phantoms (XCAT). In the population study, clinically relevant chest localizer protocols were simulated with the x‐ray tube in anterior–posterior (AP), right lateral, and PA positions. Mean organ doses and associated standard deviations (in mGy) were then estimated for all simulations. The obtained organ doses were studied as a function of patient chest diameter. Organ doses for breast and lung were compared across different views and represented as a percentage of organ doses from rotational CT scans.

Results

The validation study showed an agreement between the Monte Carlo and physical TLD measurements with a maximum percent difference of 15.5% and a mean difference of 3.5% across all organs. The XCAT population study showed that breast dose from AP localizers was the highest with a mean value of 0.24 mGy across patients, while the lung dose was relatively consistent across different localizer geometries. The organ dose estimates were found to vary across the patient population, partially explained by the changes in the patient chest diameter. The average effective dose was 0.18 mGy for AP, 0.09 mGy for lateral, and 0.08 mGy for PA localizer.

Conclusion

A platform to estimate organ doses in CT localizer scans using Monte Carlo methods was implemented and validated based on comparison with physical dose measurements. The simulation platform was applied to a virtual patient population, where the localizer organ doses were found to range within 0.4%–8.6% of corresponding organ doses for a typical CT scan, 0.2%–3.3% of organ doses for a CT pulmonary angiography scan, and 1.1%–20.8% of organ doses for a low‐dose lung cancer screening scan.