bluuebunny/crossref_metadata_2025_split huggingface dataset:
Implications of Cu and Ni toxicity in two members of the Hyalella azteca cryptic species complex: Mortality, growth, and bioaccumulation parameters
Authors: Leung Jessica , Witt Jonathan D. S. , Norwood Warren , Dixon D. George 
Published: April 2016

Abstract

Hyalella azteca, an amphipod crustacean, is frequently used in freshwater toxicity tests. Since the mid-1980s, numerous organizations have collected and established cultures of H. azteca originating from localities across North America. However, H. azteca is actually a large cryptic species complex whose members satisfy both the biological and the phylogenetic species concepts. Genetic analysis at the mitochondrial COI gene has revealed that only 2 clades are cultured in 17 North American laboratories; however, there are 85 genetically divergent lineages within this complex in the wild. In the present study, 2 members (clades 1 and 8) of the H. azteca species complex were identified using the mitochondrial COI gene. These 2 clades were exposed to Cu or Ni for 14 d. A saturation-based mortality model and the general growth model were used to determine mortality (lethal concentration, 25% and 50% [LC25 and LC50], lethal body concentration, 25% and 50% [LBC25 and LBC50]) and growth (inhibitory concentration, 25% [IC25, IBC25]) endpoints, respectively. A modified saturation-based model was used to estimate metal bioaccumulation parameters. Clade 8 was significantly more tolerant than clade 1, with differences in LC50s. However, the effects of the metals on growth were not significantly different between clades, even though clade 1 was significantly larger than then clade 8. Differences in Cu or Ni bioaccumulation were not observed between clades 1 and 8. The differences in Cu and Ni LC50s may have implications for risk assessments, and it is recommended that toxicity experiments should only be performed with properly identified members of the H. azteca complex to maintain consistency among laboratories. Environ Toxicol Chem 2016;35:2817–2826. © 2016 SETAC
Population‐based validation of the recursive partitioning analysis–based staging system for oropharyngeal cancer
Authors: Keane Florence K. , Chen Yu‐Hui , Tishler Roy B. , Schoenfeld Jonathan D. , Haddad Robert I. , Goguen Laura A. , Catalano Paul , Neville Bridget A. , Margalit Danielle N. 
Published: April 2016

AbstractBackgroundThe American Joint Committee on Cancer (AJCC) staging system does not adequately distinguish prognostic groups in the era of human papillomavirus (HPV)‐related oropharyngeal cancer. The purpose of this study was to validate a recursive partitioning analysis (RPA)‐based stage grouping on a population‐wide level.MethodsWe identified 8427 patients in Surveillance, Epidemiology, and End Results (SEER) with nonmetastatic oropharyngeal cancer with unknown HPV‐status diagnosed from 2004 to 2008. We estimated the overall survival (OS) and head and neck cancer‐specific mortality by RPA stage and AJCC stage and compared the predictive power of the systems.ResultsRPA stage was significantly associated with OS and head and neck cancer‐specific mortality (p < .0001) with 5‐year OS of 70% for RPA‐I, 55.6% for RPA‐II, and 44.3% for RPA‐III. AJCC stage failed to divide patients into distinct subgroups. RPA stage had significantly improved predictive ability versus AJCC stage for OS (c‐statistic: 0.60 = RPA vs 0.54 = AJCC) and head and neck cancer‐specific mortality (c‐statistic: 0.62 = RPA vs 0.55 = AJCC).ConclusionThe RPA‐based stage grouping divided patients into prognostically distinct cohorts and provided superior prediction of OS and head and neck cancer‐specific mortality compared to AJCC staging. © 2016 Wiley Periodicals, Inc. Head Neck 38: First–1538, 2016
Vertical surface water–groundwater exchange processes within a headwater floodplain induced by experimental floods
Authors: Hester Erich T. , Guth Christopher R. , Scott Durelle T. , Jones Charles N. 
Published: April 2016

AbstractRestoring hydrologic connectivity between channels and floodplains is common practice in stream and river restoration. Floodplain hydrology and hydrogeology impact stream hydraulics, ecology, biogeochemical processing, and pollutant removal, yet rigorous field evaluations of surface water–groundwater exchange within floodplains during overbank floods are rare. We conducted five sets of experimental floods to mimic floodplain reconnection by pumping stream water onto an existing floodplain swale. Floods were conducted throughout the year to capture seasonal variation and each involved two replicate floods on successive days to test the effect of varying antecedent moisture. Water levels and specific conductance were measured in surface water, soil, and groundwater within the floodplain, along with surface flow into and out of the floodplain. Vegetation density varied seasonally and controlled the volume of surface water storage on the floodplain. By contrast, antecedent moisture conditions controlled storage of water in floodplain soils, with drier antecedent moisture conditions leading to increased subsurface storage and slower flood wave propagation across the floodplain surface. The site experienced spatial heterogeneity in vertical connectivity between surface water and groundwater across the floodplain surface, where propagation of hydrostatic pressure, preferential flow, and bulk Darcy flow were all mechanisms that may have occurred during the five floods. Vertical connectivity also increased with time, suggesting higher frequency of floodplain inundation may increase surface water–groundwater exchange across the floodplain surface. Understanding the variability of floodplain impacts on water quality noted in the literature likely requires better accounting for seasonal variations in floodplain vegetation and antecedent moisture as well as heterogeneous exchange flow mechanisms. Copyright © 2016 John Wiley & Sons, Ltd.
Role of Sinomenine on Complete Freund's Adjuvant‐Induced Arthritis in Rats
Authors: Lan Zhou , Wei Meng , Chen Lvyi , Xie Guangjing , Liu Xiao , Zhang Xiuqiao 
Published: April 2016

AbstractThe investigation was undertaken to evaluate the effect of sinomenine (Sin) on experimental adjuvant arthritis rats stimulated by Freund's complete adjuvant and explore the corresponding potential molecular mechanism. The content of proinflammatory cytokines such as tumor necrosis factor‐alpha, interleukin‐1 beta and interleukin‐6 were detected. Besides, canonical nuclear factor kappa B (NF‐κB) pathway was also assessed to evaluate the antiarthritic potential of sinomenine. Pathological sections of rat paws showed sinomenine and diclofenac sodium significantly alleviated articular cartilage lesion, cellular infiltration, epithelial cell degeneration, synovial tissue vasodilation and congestion. The phosphorylations of inhibitor of kappaB alpha and NF‐κB subunit p65 were downregulated with the treatment of sinomenine in dose dependent manners, as well as proinflammatory cytokines. Therefore, it was assumed that sinomenine might be a new therapeutic candidate to treat arthritis. © 2016 IUBMB Life, 68(6):429–435, 2016
Nitrobindin: An Ubiquitous Family of All β‐Barrel Heme‐proteins
Authors: De Simone Giovanna , Ascenzi Paolo , Polticelli Fabio 
Published: April 2016

AbstractRhodnius prolixus nitrophorins (Rp‐NPs), Arabidopsis thaliana nitrobindin (At‐Nb), and Homo sapiens THAP4 (Hs‐THAP4) are the unique known proteins that use a β‐barrel fold to bind ferric heme, which is devoted to NO transport and/or catalysis. The eight‐stranded antiparallel β‐barrel Rp‐NPs, which represent the only heme‐binding lipocalins, are devoted to deliver NO into the blood vessel of the host and to scavenge histamine during blood sucking. Regarding Nbs, crystallographic data suggest the ability of At‐Nb and Hs‐THAP4 to bind ferric heme; however, no data are available with respect to these functions in the natural host. Here, a bioinformatics investigation based on the amino acid sequences and three‐dimensional structures of At‐Nb and Hs‐THAP4 suggests a conservation of the 10‐stranded antiparallel β‐barrel Nb structural module in all life kingdoms of the evolutionary ladder. In particular, amino acid residues involved in the heme recognition and in the structure stabilization of the Nb structural module are highly conserved (identity > 29%; homology > 83%). Moreover, molecular models of putative Nbs from different organisms match very well with each other and known three‐dimensional structures of Nbs. Furthermore, phylogenetic tree reconstruction indicates that NPs and Nbs group in distinct clades. These data indicate that 10‐stranded β‐barrel Nbs constitute a new ubiquitous heme protein family spanning from bacteria to Homo sapiens. © 2016 IUBMB Life, 68(6):423–428, 2016
CTCF‐mediated Chromatin Loop for the Posterior Hoxc Gene Expression in MEF Cells
Authors: Min Hyehyun , Kong Kyoung‐Ah , Lee Ji‐Yeon , Hong Chang‐Pyo , Seo Seong‐Hye , Roh Tae‐Young , Bae Sun Sik , Kim Myoung Hee 
Published: April 2016

AbstractModulation of chromatin structure has been proposed as a molecular mechanism underlying the spatiotemporal collinear expression of Hox genes during development. CCCTC‐binding factor (CTCF)‐mediated chromatin organization is now recognized as a crucial epigenetic mechanism for transcriptional regulation. Thus, we examined whether CTCF‐mediated chromosomal conformation is involved in Hoxc gene expression by comparing wild‐type mouse embryonic fibroblast (MEF) cells expressing anterior Hoxc genes with Akt1 null MEFs expressing anterior as well as posterior Hoxc genes. We found that CTCF binding between Hoxc11 and ‐c12 is important for CTCF‐mediated chromosomal loop formation and concomitant posterior Hoxc gene expression. Hypomethylation at this site increased CTCF binding and recapitulated the chromosomal conformation and posterior Hoxc gene expression patterns observed in Akt1 null MEFs. From this work we found that CTCF at the C12|11 does not function as a barrier/boundary, instead let the posterior Hoxc genes switch their interaction from inactive centromeric to active telomeric genomic niche, and concomitant posterior Hoxc gene expression. Although it is not clear whether CTCF affects Hoxc gene expression solely through its looping activity, CTCF‐mediated chromatin structural modulation could be an another tier of Hox gene regulation during development. © 2016 IUBMB Life, 68(6):436–444, 2016
Airborne nanoparticles (PM0.1) induce autophagic cell death of human neuronal cells
Authors: Jeon Yu‐Mi , Lee Mi‐Young 
Published: April 2016

AbstractAirborne nanoparticles PM0.1 (<100 nm in diameter) were collected and their chemical composition was determined. Al was by far the most abundant metal in the PM0.1 followed by Zn, Cr, Mn, Cu, Pb and Ni. Exposure to PM0.1 resulted in a cell viability decrease in human neuronal cells SH‐SY5Y in a concentration‐dependent manner. Upon treatment with N‐acetylcysteine, however, cell viability was significantly recovered, suggesting the involvement of reactive oxygen species (ROS). Cellular DNA damage by PM0.1 was also detected by the Comet assay. PM0.1‐induced autophagic cell death was explained by an increase in the expression of microtubule‐associated protein light chain 3A‐ІІ (LC3A‐ІІ) and autophagy‐related protein Atg 3 and Atg 7. Analysis of 2‐DE gels revealed that six proteins were upregulated, whereas eight proteins were downregulated by PM0.1 exposure. Neuroinflammation‐related lithostathine and cyclophilin A complexed with dipeptide Gly‐Pro, autophagy‐related heat shock protein gp96 and neurodegeneration‐related triosephosphate isomerase were significantly changed upon exposure to PM0.1. These results, taken together, suggest that PM0.1‐induced oxidative stress via ROS generation plays a key role in autophagic cell death and differential protein expressions in SH‐SY5Y cells. This might provide a plausible explanation for the underlying mechanisms of PM0.1 toxicity in neuronal cells and even the pathogenesis of diseases associated with its exposure. Copyright © 2016 John Wiley & Sons, Ltd.
Impact of silver nanoparticles on marine diatom Skeletonema costatum
Authors: Huang Jun , Cheng Jinping , Yi Jun 
Published: April 2016

AbstractWhen silver nanoparticles (AgNPs) are used commercially at a large scale, they infiltrate the environment at a rapid pace. However, the impact of large quantities of AgNPs on aquatic ecosystems is still largely unknown. In aquatic ecosystems, the phytoplanktons have a vital ecological function and, therefore, the potential impact of AgNPs on the microalgae community has elicited substantial concern. Therefore, in this study, the impacts of AgNPs on a marine diatom, the Skeletonema costatum, are investigated, with a focus on their photosynthesis and associated mechanisms. Exposure to AgNPs at a concentration of 0.5 mg l−1 significantly induces excess intracellular reactive oxygen species (ROS, 122%) and reduces 28% of their cell viability. More importantly, exposure to AgNPs reduces the algal chlorophyll‐a content. Scanning electron microscopy (SEM) was conducted, which revealed that AgNPs obstruct the light absorption of algae because they adhere to their surface. The maximum photochemical efficiency of photosystem II (Fv/Fm) demonstrates that exposure to AgNPs significantly inhibits the conversion of light energy into photosynthetic electron transport. Moreover, the genes of the photosystem II reaction center protein (D1) are significantly down‐regulated (P < 0.05) upon exposure to 5 mg l−1 AgNPs. These results suggest that the physical adhesion and effects of shading of AgNPs on algae might affect their light energy delivery system and damage the crucial protein function of PSII. The photosynthesis inhibition effect of AgNPs is largely different from Ag+. This study shows that AgNPs at higher concentrations might have serious consequences for the succession of the phytoplankton communities and aquatic ecosystem equilibrium. Copyright © 2016 John Wiley & Sons, Ltd.
A 28‐year observational study of urinary cadmium and β2‐microglobulin concentrations in inhabitants in cadmium‐polluted areas in Japan
Authors: Duc Phuc Hoang , Kido Teruhiko , Dung Manh Ho , Thai Anh Le , Phuong Oanh Nguyen Thi , Okamoto Rie , Ichimori Akie , Nogawa Kazuhiro , Suwazono Yasushi , Nakagawa Hideaki 
Published: April 2016

AbstractThe biological half‐life of cadmium (Cd) is as long as 10–30 years. Exposure to this element induces renal tubular dysfunction, which is considered irreversible. β2‐microglobulin (β2‐MG) is a low‐molecular‐weight protein, and urinary β2‐MG is one of the most useful and critical indicators for the early detection of renal tubular dysfunction. However, very little research has been published concerning the long‐term observation of Cd‐induced adverse health effects. As such, this follow‐up study was conducted for 28 years to clarify the relationship between the concentration of Cd and β2‐MG in the urine of 28 inhabitants (14 male and 14 female) living in the Kakehashi River basin, Ishikawa prefecture (Japan), previously one of the most highly Cd‐polluted regions in this country. All subjects were over 60 years old in 2014 and participated in all six health examinations conducted over 28 years (1986–2014). Urine was collected at the appropriate time and kept frozen to analyze urinary Cd and β2‐MG concentrations. The urinary Cd concentration was found to decrease by nearly half between 1986 and 2008 in both male and female subjects, whereas it increased significantly from 2008 to 2014 in males. In contrast, urinary β2‐MG concentrations tended to increase over the 28‐year study period in both sexes. Urinary Cd and β2‐MG concentrations in females were significantly higher than those in males in this Cd‐polluted region. Age is more strongly associated with urinary β2‐MG concentration than recent Cd body burden. Copyright © 2016 John Wiley & Sons, Ltd.
Application of corneal tomography before keratorefractive procedure for laser vision correction
Authors: Luz Allan , Lopes Bernardo , Salomão Marcela , Ambrósio Renato 
Published: April 2016

Ectasia after refractive surgery represents a major concern among refractive surgeons. Corneal abnormalities and preexisting corneal ectasia are the most important risk factors. Corneal topography and central corneal thickness are the factors traditionally screening for in refractive surgery candidates. Study of the anterior surface by Placido topography allows for identification of keratoconus before biomicroscopy. However, this is insufficient for the evaluation of pre‐operative refractive surgery. There are cases of ectasia after laser in situ keratomilusis (LASIK) without identifiable risk factors such that there is a need to go beyond the corneal surface. A key requirement is quantifying susceptibility to corneal biomechanical instability and progression to ectasia. Tomographic indices derived from elevation maps and pachymetry spatial variation produce a Belin Ambrosio display final D index (BAD‐D index), which has shown better results compared to surface curvature indices for detecting very mild forms of ectasia. A logistic regression formula, integrating age, residual stromal bed, and BAD‐D (Ectasia Susceptibility Score, ESS) resulted in a significant improvement in accuracy, leading to 100% sensitivity and 94% specificity for detecting susceptible cases. A comprehensive corneal structural analysis based on corneal segmental tomography can detect susceptible corneas, which increases safety for refractive surgery patients.
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Third generation poly(hydroxyacid) composite scaffolds for tissue engineering
Authors: Goonoo Nowsheen , Bhaw‐Luximon Archana , Passanha Pearl , Esteves Sandra R. , Jhurry Dhanjay 
Published: April 2016

AbstractBone tissue engineering based on scaffolds is quite a complex process as a whole gamut of criteria needs to be satisfied to promote cellular attachment, proliferation and differentiation: biocompatibility, right surface properties, adequate mechanical performance, controlled bioresorbability, osteoconductivity, angiogenic cues, and vascularization. Third generation scaffolds are more of composite types to maximize biological–mechanical–chemical properties. In the present review, our focus is on the performance of micro‐organism‐derived polyhydroxyalkanoates (PHAs)—polyhydroxybutyrate (PHB) and polyhydroxybutyrate‐co‐valerate (PHBV)—composite scaffolds with ceramics and natural polymers for tissue engineering applications with emphasis on bone tissue. We particularly emphasize on how material properties of the composites affect scaffold performance. PHA‐based composites have demonstrated their biocompatibility with a range of tissues and their capacity to induce osteogenesis due to their piezoelectric properties. Electrospun PHB/PHBV fiber mesh in combination with human adipose tissue‐derived stem cells (hASCs) were shown to improve vascularization in engineered bone tissues. For nerve and skin tissue engineering applications, natural polymers such as collagen and chitosan remain the gold standard but there is scope for development of scaffolds combining PHAs with other natural polymers which can address some of the limitations such as brittleness, lack of bioactivity and slow degradation rate presented by the latter. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 1667–1684, 2017.
The biological response to orthopedic implants for joint replacement. II: Polyethylene, ceramics, PMMA, and the foreign body reaction
Authors: Gibon Emmanuel , Córdova Luis A. , Lu Laura , Lin Tzu‐Hua , Yao Zhenyu , Hamadouche Moussa , Goodman Stuart B. 
Published: April 2016

AbstractNovel evidence‐based prosthetic designs and biomaterials facilitate the performance of highly successful joint replacement (JR) procedures. To achieve this goal, constructs must be durable, biomechanically sound, and avoid adverse local tissue reactions. Different biomaterials such as metals and their alloys, polymers, ceramics, and composites are currently used for JR implants. This review focuses on (1) the biological response to the different biomaterials used for TJR and (2) the chronic inflammatory and foreign‐body response induced by byproducts of these biomaterials. A homeostatic state of bone and surrounding soft tissue with current biomaterials for JR can be achieved with mechanically stable, infection free and intact (as opposed to the release of particulate or ionic byproducts) implants. Adverse local tissue reactions (an acute/chronic inflammatory reaction, periprosthetic osteolysis, loosening and subsequent mechanical failure) may evolve when the latter conditions are not met. This article (Part 2 of 2) summarizes the biological response to the non‐metallic materials commonly used for joint replacement including polyethylene, ceramics, and polymethylmethacrylate (PMMA), as well as the foreign body reaction to byproducts of these materials. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 1685–1691, 2017.
Denosumab Reduces Cortical Porosity of the Proximal Femoral Shaft in Postmenopausal Women With Osteoporosis
Authors: Zebaze Roger , Libanati Cesar , McClung Michael R , Zanchetta José R , Kendler David L , Høiseth Arne , Wang Andrea , Ghasem-Zadeh Ali , Seeman Ego 
Published: April 2016

ABSTRACT

Hip fractures account for over one-half the morbidity, mortality, and cost associated with osteoporosis. Fragility of the proximal femur is the result of rapid and unbalanced bone remodeling events that excavate more bone than they deposit, producing a porous, thinned, and fragile cortex. We hypothesized that the slowing of remodeling during treatment with denosumab allows refilling of the many cavities excavated before treatment now opposed by excavation of fewer new resorption cavities. The resulting net effect is a reduction in cortical porosity and an increase in proximal femur strength. Images were acquired at baseline and 36 months using multidetector CT in 28 women receiving denosumab and 22 women receiving placebo in a substudy of FREEDOM, a randomized, double-blind, placebo-controlled trial involving women with postmenopausal osteoporosis. Porosity was quantified using StrAx1.0 software. Strength was estimated using finite element analysis. At baseline, the higher the serum resorption marker, CTx, the greater the porosity of the total cortex (r = 0.34, p = 0.02), and the higher the porosity, the lower the hip strength (r = –0.31, p = 0.03). By 36 months, denosumab treatment reduced porosity of the total cortex by 3.6% relative to baseline. Reductions in porosity relative to placebo at 36 months were 5.3% in total cortex, 7.9% in compact-appearing cortex, 5.6% in outer transitional zone, and 1.8% in inner transitional zone (all p &lt; 0.01). The improvement in estimated hip integral strength of 7.9% from baseline (p &lt; 0.0001) was associated with the reduction in total porosity (r = –0.41, p = 0.03). In summary, denosumab reduced cortical porosity of the proximal femoral shaft, resulting in increased mineralized matrix volume and improved strength, changes that may contribute to the reduction in hip and nonvertebral fractures reported with denosumab therapy. © 2016 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals, Inc. on behalf of American Society for Bone and Mineral Research (ASBMR).