bluuebunny/crossref_metadata_2025_split huggingface dataset:
Fine structure of the retinal epithelium and tapetum lucidum of the opossum (didelphis virginiana)
Authors: Braekevelt C. R. 
Published: February 2013

AbstractThe fine structure of the retinal epithelium has been studied by electron microscopy in the opossum (Didelphis virginiana). The retinal epithelium, over most of the retina, is typical of that in other vertebrates and consists of a single layer of heavily pigmented, cuboidal cells. These cells display extensive basal (scleral) infoldings and numerous apical (vitreal) processes which enclose photoreceptor outer segments.A semicircular area of the retinal epithelium in the superior fundus is further specialized as a tapetum lucidum. The reflecting material consists of a large quantity of lipoidal spheres scattered throughout the epithelial cells. Centrally in the tapetal area very few or no melanosomes are found, indicating a non‐occlusible tapetum. Peripherally in the tapetum, the epithelial cells contain both reflecting material and melanosomes. As in the non‐tapetal area, the epithelial cells of the tapetum display large amounts of smooth endoplasmic reticulum and numerous mitochondria.Bruch's membrane everywhere displays the usual pentalaminate structure described for most vertebrates. The choriocapillaris is also typical, in that numerous fenestrations are present in the endothelium bordering Bruch's membrane.
Comparative gastrointestinal morphology of three small mammalian insectivores: Acomys spinosissimus (Rodentia), Crocidura cyanea (Eulipotyphla), and Amblysomus hottentotus (Afrosoricida)
Authors: Boonzaier Julia , Van der Merwe Elizabeth L. , Bennett Nigel C. , Kotzé Sanet H. 
Published: February 2013

AbstractThe gastrointestinal morphology was investigated in three mammalian insectivorous species, namely Acomys spinosissimus, Crocidura cyanea, and Amblysomus hottentotus. The aim of the study was to provide a comprehensive morphological comparison between the different species and to explore whether anatomical gastrointestinal adaptations are associated with the insectivorous diet of these species. The shape, proportional length, and proportional surface areas of the different gastrointestinal regions were recorded and compared in the three insectivores. Hematoxylin and Eosin (H&E) and Alcian Blue/Periodic Acid Schiff (AB/PAS) were used for morphological assessment. In all three species, the stomach was simple and uncompartmentalized. The internal aspect of the stomach in A. spinosissimus was hemi‐glandular, containing stratified squamous epithelium in the fundus, with glandular epithelium in the body and pyloric region. However, C. cyanea and A. hottentotus had wholly glandular stomachs. Paneth cells were not observed in the intestinal tracts of C. cyanea and A. hottentotus. Acomys spinosissimus was the only species studied that had a cecum. The proximal colonic region of A. spinosissimus had V‐shaped mucosal folds. Histologically, C. cyanea had villi throughout the entire gastrointestinal tract (GIT), whereas for A. hottentotus villi were not present in the most distal gastrointestinal regions. In both C. cyanea and A. hottentotus, longitudinal mucosal folds were present in the distal part of the colon. The GITs of C. cyanea and A. hottentotus showed little morphological differentiation namely, a simple, glandular stomach and the lack of a cecum. J. Morphol., 2013. © 2013 Wiley Periodicals, Inc.
Human milk can neutralize Coxsackievirus B4 in vitro
Authors: Sane F. , Alidjinou E.K. , Kacet N. , Moukassa D. , Charlet C. , Ebatetou‐Ataboho E. , Ngoulou W. , Badia‐Boungou F. , Romond M.B. , Hober D. 
Published: February 2013

AbstractThe role of enteroviruses in type 1 diabetes has long been suspected. A lower risk of type 1 diabetes is associated with breastfeeding, which could be due to a protective effect against enteroviruses. The neutralizing activity of breast milk against CVB4, a representative of enteroviruses was investigated in this study in vitro. Breast milk was cytotoxic to Hep‐2 cells up to a dilution of 1/32, whereas the aqueous fraction obtained after centrifugation was not cytotoxic; although it inhibited the cytopathic effect of CVB4 on Hep‐2 cell monolayers. The anti‐CVB4 neutralizing activity of aqueous fractions of breast milk from 49 donors living in Northern France and 15 donors living in Congo, where enteroviral infections are more prevalent, were determined. The levels of colostrum activity expressed as titre ranged from <2 to 32 in 36% of the donors from France whereas they were >128 in every donor from Congo. Pasteurized colostrum had a lower anti‐CVB4 activity compared to fresh samples (P < 0.0001, n = 49). The treatment of colostrum samples with jacalin‐coated beads that bind specifically to human IgA, showed that IgA plays a role in anti‐CVB4 activity. There was no correlation between the neutralizing activities of breast milk and serum (P = 0.37, n = 25). The current study showed that the variations in anti‐CVB4 activity in breast milk can be attributed to environmental and living conditions. Whether a low protective activity of breast milk against enteroviruses expose newborns to a higher risk of type 1 diabetes deserves further investigation. J. Med. Virol. 85:880–887, 2013. © 2013 Wiley Periodicals, Inc.
HeLa cell heterogeneity and coxsackievirus B3 cytopathic effect: Implications for inter‐laboratory reproducibility of results
Authors: Carson Steven D. , Pirruccello Samuel J. 
Published: February 2013

AbstractConcerns over cell line identities and contamination have led investigators to acquire fresh stocks of HeLa CCL‐2 cells, but results with the HeLa CCL‐2 cells do not always reproduce results with HeLa cells that have long history in the laboratory. When used for TCID50 assays of Coxsackievirus B3/28 (CVB3/28), HeLa CCL‐2 cells returned titers for CVB3/28 that were more than ten‐fold lower than titers obtained using laboratory HeLa cells. The viral cytopathic effect was less distinct in the HeLa CCL‐2 cultures, suggestive of a mixed population of cells with varied susceptibility to viral cytopathic effect. Analysis of short tandem repeat markers confirmed the identities of the cell lines as HeLa. Subpopulations in the HeLa CCL‐2 culture, separated easily based on the speed with which they were released by trypsin‐EDTA, differed in their susceptibilities to CVB3/28 cytopathic effect, and in their expression of the Coxsackievirus and adenovirus receptor (CAR). The distinctions between Lab HeLa and HeLa CCL‐2 cells were less obvious when infected with CVB3/RD, a strain selected for growth in RD cells. Results that differ among laboratories may be due to the use of HeLa cell strains with different histories, and experiments using HeLa CCL‐2 available from the American Type Culture Collection are probably incapable of reproducing many of the published studies of Coxsackievirus that have used HeLa cells with laboratory‐dependent histories. J. Med. Virol. 85:677–683, 2013. © 2013 Wiley Periodicals, Inc.
Human adipose tissue‐derived mesenchymal stem cells improve cognitive function and physical activity in ageing mice
Authors: Park Dongsun , Yang Goeun , Bae Dae Kwon , Lee Sun Hee , Yang Yun‐Hui , Kyung Jangbeen , Kim Dajeong , Choi Ehn‐Kyoung , Choi Kyung‐Chul , Kim Seung U. , Kang Sung Keun , Ra Jeong Chan , Kim Yun‐Bae 
Published: February 2013

AbstractBrain ageing leads to atrophy and degeneration of the cholinergic nervous system, resulting in profound neurobehavioral and cognitive dysfunction from decreased acetylcholine biosynthesis and reduced secretion of growth and neurotrophic factors. Human adipose tissue‐derived mesenchymal stem cells (ADMSCs) were intravenously (1 × 106 cells) or intracerebroventricularly (4 × 105 cells) transplanted into the brains of 18‐month‐old mice once or four times at 2‐week intervals. Transplantation of ADMSCs improved both locomotor activity and cognitive function in the aged animals, in parallel with recovery of acetylcholine levels in brain tissues. Transplanted cells differentiated into neurons and, in part, into astrocytes and produced choline acetyltransferase proteins. Transplantation of ADMSCs restored microtubule‐associated protein 2 in brain tissue and enhanced Trk B expression and the concentrations of brain‐derived neurotrophic factor and nerve growth factor. These results indicate that human ADMSCs differentiate into neural cells in the brain microenvironment and can restore physical and cognitive functions of aged mice not only by increasing acetylcholine synthesis but also by restoring neuronal integrity that may be mediated by growth/neurotrophic factors. © 2013 Wiley Periodicals, Inc.
Increased expression of AGS3 in rat brain cortex after traumatic brain injury
Authors: Wang Wei , Li Qi , Zou Feihui , Yu Zhihua , Wang Yunfeng , Lu Ting , Hu Tong , Cui Gang 
Published: February 2013

AbstractReceptor‐independent activators of G protein signaling (AGS) offer alternative modes of signal processing for the G protein signaling system that has broad mechanistic and functional significance. Previous studies have demonstrated that AGS3, which belongs to the AGS family, is involved in a number of different cellular activities. However, the distribution and function of AGS3 in the central nervous system (CNS) remain unclear. To investigate whether AGS3 is involved in CNS injury and repair, we used an acute traumatic brain injury (TBI) model in adult rats. Western blot analysis and immunohistochemistry showed a significant upregulation of AGS3 in ipsilateral peritrauma cortex. Double immunofluorescence staining showed that AGS3 was coexpressed with NeuN but rarely with glial fibrillary acidic protein. In addition, we detected that active caspase‐3 had colocalization with NeuN and AGS3, suggesting that AGS3 might be involved in the neuron apoptosis after TBI. To investigate the potential function of AGS3 further, a neuronal cell line, PC12, was employed to establish a cell apoptosis model. Western blot analysis indicated that AGS3 shared a similar dynamic variation in animal experiments, and phosphorylated cyclic AMP response element‐binding protein (CREB) increased in parallel. Additionally, knocking down AGS3 with siRNA partially attenuated the protein level of phosphorylated CREB in PC12 stimulated by H2O2, while reinforcing active caspase‐3 expression, demonstrating a probable antiapoptotic role through CREB played by AGS3 in neuronal apoptosis. We hypothesize that AGS3 might play an important antiapoptotic role through enhancing phosphorylation of CREB. © 2013 Wiley Periodicals, Inc.
Valproic acid attenuates microgliosis in injured spinal cord and purinergic P2X4 receptor expression in activated microglia
Authors: Lu Wen‐Hsin , Wang Chih‐Yen , Chen Po‐See , Wang Jing‐Wen , Chuang De‐Maw , Yang Chung‐Shi , Tzeng Shun‐Fen 
Published: February 2013

AbstractPeripheral injection with a high dose of valproic acid (VPA), a histone deacetylase (HDAC) inhibitor, into animals with mild or moderate spinal cord injury (SCI) for 1 week can reduce spinal cord tissue loss and promote hindlimb locomotor recovery. A purinergic adenosine triphosphate (ATP) receptor subtype, P2X4 receptor (P2X4R), has been considered as a potential target to diminish SCI‐associated inflammatory responses. In this study, using a minipump‐based infusion system, we found that intraspinal infusion with VPA for 3 days into injured spinal cord significantly improved hindlimb locomotion of rats with severe SCI induced by a 10‐g NYU impactor dropping from the height of 50 mm onto the spinal T9/10 segment. The neuronal fibers in the injured spinal cord tissues were significantly preserved in VPA‐treated rats compared with those observed in vehicle‐treated animals. Moreover, the accumulation of microglia/macrophages and astrocytes in the injured spinal cord was attenuated in the animal group receiving VPA infusion. VPA also significantly reduced P2X4R expression post‐SCI. Furthermore, in vitro study indicated that VPA, but not the other HDAC inhibitors, sodium butyrate and trichostatin A (TSA), caused downregulation of P2X4R in microglia activated with lipopolysaccharide (LPS). Moreover, p38 mitogen‐activated protein kinase (MAPK)‐triggered signaling was involved in the effect of VPA on the inhibition of P2X4R gene expression. In addition to the findings from others, our results also provide important evidence to show the inhibitory effect of VPA on P2X4R expression in activated microglia, which may contribute to reduction of SCI‐induced gliosis and subsequently preservation of spinal cord tissues. © 2013 Wiley Periodicals, Inc.
A Path to Passion: Connecting Personality, Psychological Conditions, and Emotional Engagement
Authors: Wildermuth Cristina de Mello e Souza , Vaughan Amy Grace , Christo‐Baker Elizabeth Anne 
Published: February 2013

AbstractThe focus of this study was emotional engagement, or a strong emotional attachment to one's work (Kahn, 1990). The purpose of the study was to determine the relationship among five factors of personality (need for stability, extraversion, originality, accommodation, and consolidation); psychological conditions of engagement; person–work fit, and the emotional engagement of human resource senior leaders, managers, and generalists. Structural equation modeling was completed separately for each of the three job categories. The results supported significant direct relationships among personality factors and emotional engagement but suggested that meaningfulness, availability, and person–work fit also moderate these relationships. This study makes three main contributions to the literature on the topic. First, although previous research (May, Gilson, & Harter, 2004; Rothmann & Rothmann, 2010) investigated engagement in general, this study spotlighted emotional engagement. Second, this study drew a path leading from personality to emotional engagement, moderated by psychological engagement conditions. Third, this study focused on human resource professionals, who hitherto had received scant coverage in the literature. This study proposes an emotional engagement formula that accounts for a large portion of the variability in emotional engagement (58% for managers, 61% for generalists, and 62% for senior leaders).
A sensitive method for determination of allergenic fragrance terpene hydroperoxides using liquid chromatography coupled with tandem mass spectrometry
Authors: Rudbäck Johanna , Islam Nurul , Nilsson Ulrika , Karlberg Ann‐Therese 
Published: February 2013

Different compositions of monoterpenes are utilized for their pleasant scent in cosmetics and perfumes. However, the most commonly used fragrance terpenes easily oxidize upon contact with air, forming strongly skin‐sensitizing hydroperoxides. Due to their thermolability and low UV absorbance, detection methods for hydroperoxides are scarce. For the first time, a simple and sensitive method using LC/ESI‐MS/MS was developed to quantitatively determine hydroperoxides from the common fragrance compounds linalool, linalyl acetate, and limonene. The method was applied to autoxidized petitgrain oil and sweet orange oil. A separation was accomplished using a C3 column. The method LOD for the investigated hydroperoxides in the essential oils was below 0.3 μg/mL, corresponding to 0.3 ppm.For prevention purposes and according to EU regulations, concentrations in cosmetics exceeding 100 ppm in “rinse‐off” and 10 ppm in “stay‐on” products of linalool and limonene must be labeled. However, the products may still contain allergens, such as hydroperoxides, formed by oxidative degradation of their parent terpenes. The sensitivity and selectivity of the presented LC/MS/MS method enables detection of hydroperoxides from the fragrance terpenes linalool, linalyl acetate, and limonene. However, for routine measurements, the method requires further validation.
Chronic leucine supplementation increases body weight and insulin sensitivity in rats on high‐fat diet likely by promoting insulin signaling in insulin‐target tissues
Authors: Li Xiang , Wang Xiaolei , Liu Rui , Ma Yan , Guo Huailan , Hao Liping , Yao Ping , Liu Liegang , Sun Xiufa , He Ka , Cao Wenhong , Yang Xuefeng 
Published: February 2013

ScopeThis study investigated the effect of chronic leucine supplementation on insulin sensitivity and the associated mechanisms in rats on high‐fat diet (HFD).Methods and resultsMale Sprague–Dawley rats were fed either normal chow diet or HFD supplemented with 0, 1.5, 3.0, and 4.5% leucine for 24 weeks. We found that chronic leucine supplementation increased insulin sensitivity together with increased body weight in rats on HFD, but had no effect on insulin sensitivity in rats on normal chow diet. The increased insulin sensitivity by leucine supplementation was not associated with altered ectopic fat accumulation in liver and muscle, plasma levels of lipids and cytokines, but is associated with reduced oxidative stress and improved insulin signaling. Chronic leucine supplementation did not enhance insulin receptor substract‐1 (IRS‐1) phosphorylation on serine 302, but elevated basal IRS‐1 phosphorylation on tyrosine 632 and improved insulin‐stimulated protein kinase B (Akt) and mammalian target of rapamycin (mTOR) phosphorylation in liver, skeletal muscle, and adipose tissue of rats on HFD rats, indicating leucine supplementation prevented HFD‐induced insulin resistance in insulin‐target tissues.ConclusionChronic leucine supplementation can increase insulin sensitivity and body weight likely by reducing oxidative stress and improving insulin signaling pathway in rats on HFD.
Unit‐level time trends and seasonality in the rate of hospital‐acquired pressure ulcers in US acute care hospitals
Authors: He Jianghua , Staggs Vincent S. , Bergquist‐Beringer Sandra , Dunton Nancy 
Published: February 2013

AbstractThis is a longitudinal study of the trend and seasonality in unit‐level hospital‐acquired pressure ulcer (HAPU) rates from 2004 to 2011, for 5447 acute care nursing units in 733 US hospitals. Unit‐level HAPU rates decreased significantly during 2004–2007 (OR = 0.91, 95% CI [0.90, 0.91]) and the decreasing trend was much stronger during 2008–2011 (OR = 0.84 [0.83, 0.85]). Seasonal variations in HAPU rates were strong and consistent during 2004–2008, with the highest HAPU rate in Quarter 1 (Jan–Mar) and the lowest rate in Quarter 3 (Jul–Sep). During 2009–2011, the magnitude of this seasonality was greatly reduced, and only HAPU rate in Quarter 1 remained significantly higher than HAPU rates in other quarters. © 2013 Wiley Periodicals, Inc. Res Nurs Health 36:171–180, 2013
Influence of sepiolite and electron beam irradiation on the structural and physicochemical properties of polyethylene/starch nanocomposites
Authors: Yasin Tariq , Nisar Muhammad , Shafiq Muhammad , Nho Young‐Chang , Ahmad Rashid 
Published: February 2013

AbstractThis study presents the influence of functionalized sepiolite and electron beam irradiation on the structural and physicochemical properties of high density polyethylene (HDPE)/starch blends. HDPE/Starch blends containing varying amounts of sepiolite [from 2 to 6 parts per hundred (phr) resins] were prepared in an internal mixer and subjected to electron beam irradiation. The structural analysis of nanocomposites revealed an interaction among the incorporated components. The morphological analysis depicted the void‐free dispersion of additives in the nanocomposites as well as an improvement in the compatibility between the matrix and additives. The sepiolite served as a heat barrier and improved the thermal stability of blend upto a maximum of 45°C. The ultimate tensile strength and Young's modulus (E) of blend was slightly improved with the incorporation of sepiolite and radiation. On the contrary, the E of nanocomposites was significantly improved with radiation dose. The sample containing 6 phr sepiolite and irradiated at 100 kGy showed 61% increase in E when compared with its unirradiated counterpart. Likewise, the thermal distortion temperature and Vicat softening temperature of the blend was slightly changed with the incorporation of sepiolite and radiation dose; however, increased with radiation dose in the nanocomposites. The improvements in the properties of nanocomposites with radiation dose were assigned to the formation of radiation‐induced crosslinked network as revealed by gel content analysis. The results presented here revealed substantial improvements in the properties of nanocomposites with irradiation, which pave way for their potential applications in various sectors including packaging materials for radiation sterilizable products. POLYM. COMPOS., 2013. © 2013 Society of Plastics Engineers
Self‐assembly and responsiveness of polypeptide‐based block copolymers: How “Smart” behavior and topological complexity yield unique assembly in aqueous media
Authors: Ray Jacob G. , Johnson Ashley J. , Savin Daniel A. 
Published: February 2013

AbstractPolypeptide‐based amphiphilic block copolymers are an attractive class of materials given their ability to form well‐defined aqueous nanoassemblies that respond to external stimulus through secondary structure transitions. This report will highlight recent literature in the area of polypeptide‐based block copolymer self‐assembly, with the major focus being on how the responsive nature and structural complexity of the polypeptide blocks can be incorporated into systems with complex topologies such as ABA/BAB/ABC triblock copolymers, AB2 and A2B star copolymers, and miktoarm μ‐ABC star terpolymers. In particular, the role of interfacial curvature changes and how they result in morphology transitions will be discussed. The ‘smart’ assembly properties of peptides in complex block copolymer topologies can lead to enhanced responsiveness, morphological complexity, and unique morphological transitions with varying solution conditions. © 2013 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2013
Physics of engineered protein hydrogels
Authors: Kim Minkyu , Tang Shengchang , Olsen Bradley D. 
Published: February 2013

AbstractArtificially engineered proteins and synthetic polypeptides have attracted widespread interest as building blocks for polymer hydrogels. The biophysical properties of the proteins, such as molecular recognition abilities, folded chain structures, and sequence‐dependent thermodynamic behavior, enable advances in functional, responsive, and tunable gels. This review discusses the design of polymer hydrogels that incorporate protein domains, highlighting new challenges in polymer physics that are presented by this emerging class of materials. Five types of engineered protein hydrogels are discussed: (a) physically associating protein polymer gels, (b) amorphous artificially engineered protein networks, (c) engineered proteins with crystalline domains, (d) stretchable protein tertiary structures in gels, and (e) protein gels with biological recognition properties. The physics of the protein component and the physical properties of the resulting hydrogels are summarized, illustrating how advances in understanding these systems are leading to exciting novel biofunctional hydrogels. © 2013 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2013