bluuebunny/crossref_metadata_2025_split huggingface dataset:
A predation assay using amoebae to screen for virulence factors unearthed the first W. chondrophila inclusion membrane protein
Authors: Kebbi-Beghdadi C. , Pilloux L. , Croxatto A. , Tosetti N. , Pillonel T. , Greub G. 
Published: December 2019

AbstractWaddlia chondrophila is an intracellular bacterium phylogenetically related to the well-studied human and animal pathogens of the Chlamydiaceae family. In the last decade, W. chondrophila was convincingly demonstrated to be associated with adverse pregnancy outcomes in humans and abortions in animals. All members of the phylum Chlamydiae possess a Type Three Secretion System that they use for delivering virulence proteins into the host cell cytosol to modulate their environment and create optimal conditions to complete their life cycle. To identify W. chondrophila virulence proteins, we used an original screening approach that combines a cosmid library with an assay monitoring resistance to predation by phagocytic amoebae. This technique combined with bioinformatic data allowed the identification of 28 candidate virulence proteins, including Wimp1, the first identified inclusion membrane protein of W. chondrophila.
Allergen-induced anxiety-like behavior is associated with disruption of medial prefrontal cortex - amygdala circuit
Authors: Dehdar Kolsoum , Mahdidoust Shirin , Salimi Morteza , Gholami-Mahtaj Leila , Nazari Milad , Mohammadi Sadeq , Dehghan Samaneh , Jamaati Hamidreza , Khosrowabadi Reza , Nasiraei-Moghaddam Abbas , Barkley Victoria , Javan Mohammad , Mirnajafi-Zadeh Javad , Sumiyoshi Akira , Raoufy Mohammad Reza 
Published: December 2019

AbstractAnxiety is prevalent in asthma, and is associated with disease severity and poor quality of life. However, no study to date provides direct experimental evidence for the effect of allergic inflammation on the structure and function of medial prefrontal cortex (mPFC) and amygdala, which are essential regions for modulating anxiety and its behavioral expression. We assessed the impact of ovalbumin (OVA)-induced allergic inflammation on the appearance of anxiety-like behavior, mPFC and amygdala volumes using MRI, and the mPFC-amygdala circuit activity in sensitized rats. Our findings exhibited that the OVA challenge in sensitized rats induced anxiety-like behavior, and led to more activated microglia and astrocytes in the mPFC and amygdala. We also found a negative correlation between anxiety-like behavior and amygdala volume. Moreover, OVA challenge in sensitized rats was associated with increases in mPFC and amygdala activity, elevation of amygdala delta-gamma coupling, and the enhancement of functional connectivity within mPFC-amygdala circuit – accompanied by an inverted direction of information transferred from the amygdala to the mPFC. We indicated that disrupting the dynamic interactions of the mPFC-amygdala circuit may contribute to the induction of anxiety-related behaviors with asthma. These findings could provide new insight to clarify the underlying mechanisms of allergic inflammation-induced psychiatric disorders related to asthma.
A novel murine model for assessing fetal and birth outcomes following transgestational maternal malaria infection
Authors: Morffy Smith Catherine D. , Russ Brittany N. , Andrew Alicer K. , Cooper Caitlin A. , Moore Julie M. 
Published: December 2019

AbstractPlasmodium falciparum infection during pregnancy is a major cause of severe maternal illness and neonatal mortality. Mouse models are important for the study of gestational malaria pathogenesis. When infected with Plasmodium chabaudi chabaudi AS in early gestation, several inbred mouse strains abort at midgestation. We report here that outbred Swiss Webster mice infected with P. chabaudi chabaudi AS in early gestation carry their pregnancies to term despite high parasite burden and malarial hemozoin accumulation in the placenta at midgestation, with the latter associated with induction of heme oxygenase 1 expression. Infection yields reduced fetal weight and viability at term and a reduction in pup number at weaning, but does not influence postnatal growth prior to weaning. This novel model allows for the exploration of malaria infection throughout pregnancy, modeling chronic infections observed in pregnant women prior to the birth of underweight infants and enabling the production of progeny exposed to malaria in utero, which is critical for understanding the postnatal repercussions of gestational malaria. The use of outbred mice allows for the exploration of gestational malaria in a genetically diverse model system, better recapitulating the diversity of infection responses observed in human populations.
The CXCL12 SNPs and their haplotypes are associated with serum lipid traits
Authors: Qiu Ling , Yin Rui-Xing , Nie Rong-Jun , Hu Xi-Jiang , Khounphinith Eksavang , Zhang Fen-Han 
Published: December 2019

AbstractThe relationship among the single nucleotide polymorphisms (SNPs) of the C-X-C motif chemokine ligand 12 gene (CXCL12) and the serum lipid profiles in the Chinese population has rarely been described, especially in somewhat old-fashioned and isolated Maonan minority. The goal of the current study was to elucidate the connection among the CXCL12 rs501120 and rs1746048 SNPs, haplotypes, several environmental factors and serum lipid traits in the Maonan as well as Han populations. Genotyping of the two SNPs, gel electrophoresis and direct sequencing were accomplished in 1,494 distinct subjects (Maonan, 750 and Han, 744) using polymerase chain reaction and restriction fragment length polymorphism. The frequencies of genotypes as well as alleles of the two SNPs were not similar between the two ethnic groups. The rs501120 SNP was related with serum total cholesterol levels, while the rs1746048 SNP was related with serum apolipoprotein (Apo) B levels. Four haplotypes were identified, of which the rs501120A-rs1746048C haplotype was the most common. The haplotypes of rs501120A-rs1746048T increased and rs501120G-rs1746048C decreased the risk of hyperlipidemia (P < 0.001 for each), showing consistent association with the levels of serum triglyceride, ApoA1 and ApoB. These outcomes specify that the CXCL12 SNPs as well as their haplotypes are related to serum lipid levels. Different serum lipid levels between both populations may partially be related to the CXCL12 SNPs, their haplotypes along with several environmental factors.
Assimilating Satellite Land Surface States Data from Fengyun-4A
Authors: Meng Chunlei , Li Huoqing 
Published: December 2019

AbstractFengyun-4A is the new generation of Chinese geostationary meteorological satellites. Land surface albedo, land surface emissivity and land surface temperature are key states for land surface modelling. In this paper, the land surface albedo, land surface emissivity and land surface temperature data from Fengyun-4A were assimilated into the Integrated Urban land Model. The Fengyun-4A data are one of the data sources for the land data assimilation system which devoted to produce the high spatial and temporal resolution, multiple parameters near real-time land data sets. The Moderate-Resolution Imaging Spectroradiometer (MODIS) LSA and LSE data, the Institute of Atmospheric Physics, China Academy of Sciences (IAP) 325 m tower observation data and the observed 5 cm and 10 cm soil temperature data in more than 100 sites are used for validation. The results indicate the MODIS land surface albedo is much smaller than the Fengyun-4A and is superior to the Fengyun-4A for the Institute of Atmospheric Physics, China Academy of Sciences 325 m tower site. The Moderate-Resolution Imaging Spectroradiometer land surface emissivity is smaller than the Fengyun-4A in barren land surface and the differences is relatively small for other land use and land cover categories. In most regions of the research area, the Fengyun-4A land surface albedo and land surface emissivity are larger than those of the simulations. After the land surface albedo assimilation, in most regions the simulated net radiation was decreased. After the land surface emissivity assimilation, in most regions the simulated net radiation was increased. After the land surface temperature assimilation, the biases of the land surface temperature were decreased apparently; the biases of the daily average 5 cm and 10 cm soil temperature were decreased.
High-temperature martensitic transformation of CuNiHfTiZr high- entropy alloys
Authors: Chang Shan-Hsiu , Lin Po-Ting , Tsai Che-Wei 
Published: December 2019

AbstractOne of the major challenges of near-equiatomic NiTi shape memory alloys is their limitation for high-temperature applications. To overcome this barrier, researchers have tried to enhance the transformation temperatures by addition of alloying elements or even by introducing the concept of high-entropy alloys (HEAs). In this study, the CuNiHfTiZr HEAs were developed for high-temperature shape memory effect. Based on their solubility and electron configurations, the alloying elements are divided into two groups, (CuNi)50 and (HfTiZr)50. The content of Cu in (CuNi)50 is modulated to investigate the influences of Cu on martensitic transformation of the HEAs by studying structural evolution and transformation behavior. The results of x-ray diffraction and thermal expansion tests revealed that Cu15Ni35Hf16.67Ti16.67Zr16.67 possesses high transformation temperature, narrow hysteresis temperature loops, and good dimensional stability within this HEA system.
Survival of a long-lived single island endemic, the Raso lark Alauda razae, in relation to age, fluctuating population and rainfall
Authors: Dierickx E. G. , Robinson R. A. , Brooke M. de L. 
Published: December 2019

AbstractEstimating and understanding variation in survival rates is crucial for the management of threatened species, especially those with limited population sizes and/or restricted ranges. Using a capture-resighting dataset covering 2004–2017, we estimate adult survival in the Raso larkAlauda razae, a Critically Endangered single-island Cape Verdean endemic, whose population varied 25-fold during the study. Average annual adult survival was similar for males (0.813 ± 0.011) and females (0.826 ± 0.011) over the period. These values are high for a temperate passerine but not unusual for an insular tropical species like the lark. The oldest bird was recorded 13 years after first ringing. There was strong evidence that survival varied among years (between 0.57 and 0.95), being generally higher in wetter years. Survival, especially of males, was lower when the population was large, but only in drier years. Survival declined with age but there was no evidence that this decline was other than linear. High survival, even in the face of dry conditions, at least when the population is depressed, has probably contributed to the persistence of the species on its 7 km2island home over several centuries.
Neutronic investigation of alternative & composite burnable poisons for the soluble-boron-free and long life civil marine small modular reactor cores
Authors: Alam Syed Bahauddin , Almutairi Bader , Ridwan Tuhfatur , Kumar Dinesh , Goodwin Cameron S. , Atkinson Kirk D. , Parks Geoffrey T. 
Published: December 2019

AbstractConcerns about the effects of global warming provide a strong case to consider how best nuclear power could be applied to marine propulsion. Currently, there are persistent efforts worldwide to combat global warming, and that also includes the commercial freight shipping sector. In an effort to decarbonize the marine sector, there are growing interests in replacing the contemporary, traditional propulsion systems with nuclear propulsion systems. The latter system allows freight ships to have longer intervals before refueling; subsequently, lower fuel costs, and minimal carbon emissions. Nonetheless, nuclear propulsion systems have remained largely confined to military vessels. It is highly desirable that a civil marine core not use soluble boron for reactivity control, but it is then a challenge to achieve an adequate shutdown margin throughout the core life while maintaining reactivity control and acceptable power distributions in the core. High-thickness ZrB2 150 μm Integral Fuel Burnable Absorber (IFBA) is an excellent burnable poison (BP) candidate for long life soluble-boron-free core. However, in this study, we want to minimize the use of 150 μm IFBA since B-10 undergoes an (n, α) capture reaction, and the resulting helium raises the pressure within the plenum and in the cladding. Therefore, we have considered several alternative and novel burnable BP design strategies to minimize the use of IFBA for reactivity control in this study: (Case 1) a composite BP: gadolinia (Gd2O3) or erbia (Er2O3) with 150 μm thickness ZrB2 IFBA; (Case 2) Pu-240 or Am-241 mixed homogeneously with the fuel; and (Case 3) another composite BP: Pu-240 or Am-241 with 150 μm thickness ZrB2 IFBA. The results are compared against those for a high-thickness 150 μm 25 IFBA pins design from a previous study. The high-thickness 150 μm 25 IFBA pins design is termed the “IFBA-only” BP design throughout this study. We arrive at a design using 15% U-235 fuel loaded into 13 × 13 assemblies with Case 3 BPs (IFBA+Pu-240 or IFBA+Am-241) for reactivity control while reducing 20% IFBA use. This design exhibits lower assembly reactivity swing and minimal burnup penalty due to the self-shielding effect. Case 3 provides ~10% more initial (beginning-of-life) reactivity suppression with ~70% less reactivity swing compared to the IFBA-only design for UO2 fuel while achieving almost the same core lifetime. Finally, optimized Case 3 assemblies were loaded in 3D nodal diffusion and reactor model code. The results obtained from the 3D reactor model confirmed that the designed core with the proposed Case 3 BPs can achieve the target lifetime of 15 years while contributing to ~10% higher BOL reactivity suppression, ~70% lower reactivity swings, ~30% lower radial form factor and ~28% lower total peaking factor compared to the IFBA-only core.
Clinical characteristics, risk factors, and surgical outcomes of secondary macular hole after vitrectomy
Authors: Kang Hyun Goo , Han Jae Yong , Choi Eun Young , Byeon Suk Ho , Kim Sung Soo , Koh Hyoung Jun , Lee Sung Chul , Kim Min 
Published: December 2019

AbstractSecondary macular hole(MH) formation after vitrectomy is rare and its risk factors and pathogenesis are not clearly understood. This retrospective study was conducted to identify the risk factors of this complication and assess outcomes at 2 tertiary centres. The primary outcomes were the clinical characteristics associated with development of secondary MH, which included the primary diagnosis for initial vitrectomy, features on optical coherence tomography, and adjuvant surgical techniques used during the initial surgery. Secondary outcomes included the change in best-corrected visual acuity(BCVA), clinical factors associated with the need for re-operations for MH closure and prognostic factors for the visual outcomes. Thirty-eight eyes out of 6,354 cases (incidence 0.60%) developed secondary MH after undergoing vitrectomy for various vitreoretinal disorders over an 11-year period, most frequently after initial surgery for retinal detachment(RD) (9 eyes) and secondary epiretinal membrane (6 eyes). The mean age was 57.1 years (range: 17.8–76.7), and the mean follow-up was 51.1 months (range: 6.8 to 137.6). Prior to secondary MH formation, development of ERM was the most common OCT feature (19 eyes, 50%), and no cases of cystoid macular oedema (CME) were observed. A greater proportion of eyes with secondary MH had long axial lengths (32% ≥26 mm vs 5% of eyes ≤22 mm). MH closure surgery was performed in 36 eyes and closure was achieved in 34 (success rate 94%, final BCVA 20/86), with ≥3-line visual gain in 18 cases. BCVA at MH onset (OR = 0.056, P = 0.036), BCVA at post-MH surgery month 3 (OR = 52.671, P = 0.011), and axial length ≥28 mm (OR = 28.487, P = 0.030) were associated with ≥3-line visual loss; a history of macula-off RD (OR = 27.158, P = 0.025) was associated with the need for multiple surgeries for MH closure. In conclusion, secondary MH occurs rarely but most commonly after vitrectomy for RD. Patients with axial length ≥28 mm and poor BCVA at 3 months post-operation may have limited visual prognosis; those with a history of macula-off RD may require multiple surgeries for hole closure.
Release of Porcine Sperm from Oviduct Cells is Stimulated by Progesterone and Requires CatSper
Authors: Machado Sergio A. , Sharif Momal , Wang Huijing , Bovin Nicolai , Miller David J. 
Published: December 2019

AbstractSperm storage in the female reproductive tract after mating and before ovulation is a reproductive strategy used by many species. When insemination and ovulation are poorly synchronized, the formation and maintenance of a functional sperm reservoir improves the possibility of fertilization. In mammals, the oviduct regulates sperm functions, such as Ca2+influx and processes associated with sperm maturation, collectively known as capacitation. A fraction of the stored sperm is released by unknown mechanisms and moves to the site of fertilization. There is an empirical association between the hormonal milieu in the oviduct and sperm detachment; therefore, we tested directly the ability of progesterone to induce sperm release from oviduct cell aggregates. Sperm were allowed to bind to oviduct cells or an immobilized oviduct glycan and then challenged with progesterone, which stimulated the release of 48% of sperm from oviduct cells or 68% of sperm from an immobilized oviduct glycan. The effect of progesterone on sperm release was specific; pregnenolone and 17α-OH-progesterone did not affect sperm release. Ca2+influx into sperm is associated with capacitation and development of hyperactivated motility. Progesterone increased sperm intracellular Ca2+, which was abrogated by blocking the sperm–specific Ca2+channel CatSper with NNC 055-0396. NNC 055-0396 also blocked the progesterone-induced sperm release from oviduct cells or immobilized glycan. An inhibitor of the non-genomic progesterone receptor that activates CatSper similarly blocked sperm release. This is the first report indicating that release of sperm from the sperm reservoir is induced by progesterone action through CatSper channels.
Phenotypic alterations in liver cancer cells induced by mechanochemical disruption
Authors: Murad Hakm Y. , Bortz Emma P. , Yu Heng , Luo Daishen , Halliburton Gray M. , Sholl Andrew B. , Khismatullin Damir B. 
Published: December 2019

AbstractHepatocellular carcinoma (HCC) is a highly fatal disease recognized as a growing global health crisis worldwide. Currently, no curative treatment is available for early-to-intermediate stage HCC, characterized by large and/or multifocal tumors. If left untreated, HCC rapidly progresses to a lethal stage due to favorable conditions for metastatic spread. Mechanochemical disruption of cellular structures can potentially induce phenotypic alterations in surviving tumor cells that prevent HCC progression. In this paper, HCC response to mechanical vibration via high-intensity focused ultrasound and a chemical disruptive agent (ethanol) was examined in vitro and in vivo. Our analysis revealed that mechanochemical disruption caused a significant overproduction of reactive oxygen species (ROS) in multiple HCC cell lines (HepG2, PLC/PRF/5, and Hep3B). This led to a decrease in cell viability and long-term proliferation due to increased expression and activity of death receptors TNFR1 and Fas. The cells that survived mechanochemical disruption had a reduced expression of cancer stem cell markers (CD133, CD90, CD49f) and a diminished colony-forming ability. Mechanochemical disruption also impeded HCC migration and their adhesion to vascular endothelium, two critical processes in hematogenous metastasis. The HCC transformation to a non-tumorigenic phenotype post mechanochemical disruption was confirmed by a lack of tumor spheroid formation in vitro and complete tumor regression in vivo. These results show that mechanochemical disruption inhibits uncontrolled proliferation and reduces tumorigenicity and aggressiveness of HCC cells through ROS overproduction and associated activation of TNF- and Fas-mediated cell death signaling. Our study identifies a novel curative therapeutic approach that can prevent the development of aggressive HCC phenotypes.
An experiment-informed signal transduction model for the role of the Staphylococcus aureus MecR1 protein in β-lactam resistance
Authors: Belluzo Bruno S. , Abriata Luciano A. , Giannini Estefanía , Mihovilcevic Damila , Dal Peraro Matteo , Llarrull Leticia I. 
Published: December 2019

AbstractThe treatment of hospital- and community-associated infections by methicillin-resistant Staphylococcus aureus (MRSA) is a perpetual challenge. This Gram-positive bacterium is resistant specifically to β-lactam antibiotics, and generally to many other antibacterial agents. Its resistance mechanisms to β-lactam antibiotics are activated only when the bacterium encounters a β-lactam. This activation is regulated by the transmembrane sensor/signal transducer proteins BlaR1 and MecR1. Neither the transmembrane/metalloprotease domain, nor the complete MecR1 and BlaR1 proteins, are isolatable for mechanistic study. Here we propose a model for full-length MecR1 based on homology modeling, residue coevolution data, a new extensive experimental mapping of transmembrane topology, partial structures, molecular simulations, and available NMR data. Our model defines the metalloprotease domain as a hydrophilic transmembrane chamber effectively sealed by the apo-sensor domain. It proposes that the amphipathic helices inserted into the gluzincin domain constitute the route for transmission of the β-lactam-binding event in the extracellular sensor domain, to the intracellular and membrane-embedded zinc-containing active site. From here, we discuss possible routes for subsequent activation of proteolytic action. This study provides the first coherent model of the structure of MecR1, opening routes for future functional investigations on how β-lactam binding culminates in the proteolytic degradation of MecI.
Predicting cognitive performance from physical activity and fitness in adolescents and young adults in Botswana relative to HIV status
Authors: Malete Leapetswe , Etnier Jennifer L. , Tladi Dawn M. , Vance Jarod C. , Anabwani Gabriel M. 
Published: December 2019

AbstractLittle is known about whether physical activity and fitness could enhance cognition in adolescents and young adults living with HIV. The purpose of this study was to examine this relationship in a group of 250 HIV+ (n = 88) and HIV negative (n = 162) participants from Botswana, aged 12–23 years (Mean = 17.87, SD = 2.24). Fitness was operationalized as muscular strength (push-ups) and aerobic endurance (PACER). PA was assessed using items from the Youth Risk Behavior Surveillance Survey. Cognition was measured using the Corsi Test, Berg Card Sorting Task (BCST), and Stroop Color Word Task (Stroop). Multiple regression analyses indicated that the HIV x push-ups interaction was a significant predictor of Corsi performance, and HIV status was a significant predictor of BCST performance (p < 0.05). For the Stroop portions, HIV status and HIV x push-ups were significant predictors (p < 0.01). HIV status is predictive of cognition and interacts with muscular fitness to predict cognition.