bluuebunny/crossref_metadata_2025_split huggingface dataset:
Porous hydroxyapatite and gelatin/hydroxyapatite microspheres obtained by calcium phosphate cement emulsion
Authors: Perez Roman A. , Del Valle Sergio , Altankov George , Ginebra Maria‐Pau 
Published: February 2011

AbstractHydroxyapatite and hybrid gelatine/hydroxyapatite microspheres were obtained through a water in oil emulsion of a calcium phosphate cement (CPC). The setting reaction of the CPC, in this case the hydrolysis of α‐tricalcium phosphate, was responsible for the consolidation of the microspheres. After the setting reaction, the microspheres consisted of an entangled network of hydroxyapatite crystals, with a high porosity and pore sizes ranging between 0.5 and 5 μm. The size of the microspheres was tailored by controlling the viscosity of the hydrophobic phase, the rotation speed, and the initial powder size of the CPC. The incorporation of gelatin increased the sphericity of the microspheres, as well as their size and size dispersion. To assess the feasibility of using the microspheres as cell microcarriers, Saos‐2 cells were cultured on the microspheres. Fluorescent staining, SEM studies, and LDH quantification showed that the microspheres were able to sustain cell growth. Cell adhesion and proliferation was significantly improved in the hybrid gelatin/hydroxyapatite microspheres as compared to the hydroxyapatite ones. © 2011 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2011.
Inhibitory effects of iron on bone morphogenetic protein 2–induced osteoblastogenesis
Authors: Yang Qing , Jian Jinlong , Abramson Steven B , Huang Xi 
Published: February 2011

Abstract
Postmenopausal osteoporosis is characterized by an imbalance of bone resorption exceeding bone formation, resulting in a net loss of bone mineral density (BMD). Estrogen deficiency is known to promote bone resorption. However, the causative factors that impair bone formation have not been identified. Women after menopause experience not only estrogen deficiency but also iron accumulation as a result of cessation of menstruation. In this study we investigated whether increased iron plays a role in osteoporosis. By growing primary mouse osteoclast and osteoblast progenitor cells as well as immortalized cell lines in the presence of iron, we found that increased iron had minimal effects on osteoclast cell differentiation. Interestingly, iron, particularly in its inorganic form, and to a lesser extent ferritin and transferrin all suppressed alkaline phosphatase (ALP) activities in osteoblasts. Moreover, iron downregulated mRNA levels of several other osteoblastogenic markers such as Runx2, osterix, osteopontin, and osteocalcin. To further show that this in vitro finding is relevant to the in vivo condition, we demonstrated that iron-accumulated mice with intact ovaries exhibited a significant decrease in BMD. Although iron inhibited preosteoblast cell differentiation, it did enhance preosteoblast cell proliferation, as evidenced by increased cell growth and expression of cell cycle regulator genes such as CDK4, CDK6, cyclin D1, and cyclin D3 and G2/M phase cell population. Taken together, our results suggest that increased iron could be a factor that slows down bone formation in postmenopausal women. © 2011 American Society for Bone and Mineral Research.
Internal migration and depressive symptoms among migrant factory workers in Shenzhen, China
Authors: Mou Jin , Cheng Jinquan , Griffiths Sian M. , Wong Samuel Y.S. , Hillier Sheila , Zhang Dan 
Published: February 2011

AbstractThere has been a dramatic increase in rural‐urban migration in China over the last two decades but there are few studies on the mental health of Chinese internal migrants. This study assesses the prevalence of depressive symptoms (DS) and their associated factors among migrant factory workers in Shenzhen, China. A questionnaire survey was sent to 4,280 migrant workers in 2009 with a response rate of 95.5%. Clinically relevant DS were identified using the Chinese version of the Centre for Epidemiologic Studies Depressive Scale. There is a high prevalence (21.4%) of clinically relevant DS among internal migrant factory workers. Higher scores were associated with being a minority, shorter intension of stay, working long hours, being a casual smoker or a frequent Internet user, and having better education. Stakeholders should be aware of the needs of these subgroups, particularly in the light of recent publicity about factory worker suicides in Shenzhen. © 2011 Wiley Periodicals, Inc.
Regulatory volume decrease and P receptor signaling in fish cells: mechanisms, physiology, and modeling approaches
Authors: Chara Osvaldo , Espelt María V. , Krumschnabel Gerhard , Schwarzbaum Pablo J. 
Published: February 2011

AbstractFor animal cell plasma membranes, the permeability of water is much higher than that of ions and other solutes, and exposure to hyposmotic conditions almost invariably causes rapid water influx and cell swelling. In this situation, cells deploy regulatory mechanisms to preserve membrane integrity and avoid lysis. The phenomenon of regulatory volume decrease, the partial or full restoration of cell volume following cell swelling, is well‐studied in mammals, with uncountable investigations yielding details on the signaling network and the effector mechanisms involved in the process. In comparison, cells from other vertebrates and from invertebrates received little attention, despite of the fact that e.g. fish cells could present rewarding model systems given the diversity in ecology and lifestyle of this animal group that may be reflected by an equal diversity of physiological adaptive mechanisms, including those related to cell volume regulation. In this review, we therefore present an overview on the most relevant aspects known on hypotonic volume regulation presently known in fish, summarizing transporters and signaling pathways described so far, and then focus on an aspect we have particularly studied over the past years using fish cell models, i.e. the role of extracellular nucleotides in mediating cell volume recovery of swollen cells. We, furthermore, present diverse modeling approaches developed on the basis of data derived from studies with fish and other models and discuss their potential use for gaining insight into the theoretical framework of volume regulation.J. Exp. Zool. 315A:175–202, 2011. © 2011 Wiley‐Liss, Inc.
The Ritual: Death Pronouncement
Authors: Carter Brian S. 
Published: February 2011

AbstractBACKGROUND:Death pronouncement comes infrequently for the pediatrician. The place of death for most children is in the hospital. For hospitalists and pediatric intensivists in the neonatal intensive care or pediatric intensive care units, death pronouncement is not uncommon. For hospitalist physicians, the call to attend a code or to pronounce a death may come on any given shift and from almost anywhere in the hospital.CONCLUSION:A demonstrative case is provided, followed by key concepts for practice and for educating trainees. Journal of Hospital Medicine 2011;6:94–97. © 2011 Society of Hospital Medicine.
Dry under water: Comparative morphology and functional aspects of air‐retaining insect surfaces
Authors: Balmert Alexander , Bohn Holger Florian , Ditsche‐Kuru Petra , Barthlott Wilhelm 
Published: February 2011

AbstractSuperhydrophobic surfaces prevent certain body parts of semiaquatic and aquatic insects from getting wet while submerged in water. The air layer on these surfaces can serve the insects as a physical gill. Using scanning electron microscopy, we investigated the morphology of air‐retaining surfaces in five insect species with different levels of adaptation to aquatic habitats. We found surfaces with either large and sparse hairs (setae), small and dense hairs (microtrichia), or hierarchically structured surfaces with both types of hairs. The structural parameters and air‐film persistence of these surfaces were compared. Air‐film persistence varied between 2 days in the beetle Galerucella nymphaea possessing only sparse setae and more than 120 days in the bugs Notonecta glauca and Ilyocoris cimicoides possessing dense microtrichia (up to 6.6 × 106 microtrichia per millimeter square). From our results, we conclude that the density of the surface structures is the most important factor that affects the persistence of air films. Combinations of setae and microtrichia are not decisive for the overall persistence of the air film but might provide a thick air store for a short time and a thin but mechanically more stable air film for a long time. Thus, we assume that a dense cover of microtrichia acts as a “backup system” preventing wetting of the body surface in case the air–water interface is pressed toward the surface. Our findings might be beneficial for the development of biomimetic surfaces for long‐term air retention and drag reduction under water. In addition, the biological functions of the different air retention capabilities are discussed. J. Morphol., 2011. © 2011 Wiley‐Liss, Inc.
Scanning electron microscopy of the placental interface in the viviparous lizard Sceloporus jarrovi (Squamata: Phrynosomatidae)
Authors: Anderson Kristie E. , Blackburn Daniel G. , Dunlap Kent D. 
Published: February 2011

AbstractPlacental membranes mediate maternal‐fetal exchange in all viviparous reptilian sauropsids. We used scanning electron microscopy to examine the placental interface in the mountain spiny lizard, Sceloporus jarrovi (Phrynosomatidae). From the late limb bud stage until birth, the conceptus is surrounded by placental membranes formed from the chorioallantois and yolk sac omphalopleure. The chorioallantois lies directly apposed to the uterine lining with no intervening shell membrane. Both fetal and maternal sides of the chorioallantoic placenta are lined by continuous layers of flattened epithelial cells that overlie dense capillary networks. The chorioallantoic placenta shows specializations that enhance respiratory exchange, as well as ultrastructural evidence of maternal secretion and fetal absorption. The yolk sac placenta contains enlarged fetal and maternal epithelia with specializations for histotrophic nutrient transfer. This placenta lacks intrinsic vascularity, although the vascular allantois lies against its inner face, contributing to an omphallantoic placenta. In a specialized region at the abembryonic pole, uterine and fetal tissues are separated by a compact mass of shed shell membrane, yolk droplets, and cellular debris. The omphalopleure in this region develops elongate folds that may contribute to sequestration and absorption of this material. Fetal membrane morphogenesis and composition in S. jarrovi are consistent with those of typical squamates. However, this species exhibits unusual placental specializations characteristic of highly placentotrophic lizards. J. Morphol., 2011. © 2011 Wiley‐Liss, Inc.
Homologies of the branchial arch muscles in Zacco platypus (Teleostei: Cypriniformes: Cyprinidae): Evidence from innervation pattern
Authors: Nakae Masanori , Sasaki Kunio , Nakajima Tsuneo , Miyazaki Yusuke , Matsuura Keiichi 
Published: February 2011

AbstractHomologies of the branchial arch muscles in the cyprinid Zacco platypus are assessed based on their innervation. Muscles serving the first gill arch are innervated by branches of the glossopharyngeal (IX) nerve and those serving other arches by the vagal (X) nerve. Absence of the levator posterior is confirmed. Five pairs of muscles originating from the cranium and inserted onto the specialized 5th ceratobranchial, all unique to cyprinids, are innervated by the 4th branchial trunks of X, indicating that all pairs are derivatives of the sphincter oesophagi, involving reorganization from intrinsic to extrinsic elements. Homologies of some ventral branchial muscles are also discussed and the criteria for homology improved by clarifying the innervation pattern. J. Morphol., 2011. © 2011 Wiley‐Liss, Inc.
γ‐Aminobutyric acid type B receptor changes in the rat striatum and substantia nigra following intrastriatal quinolinic acid lesions
Authors: Rekik Letaïef , Daguin‐Nerrière Véronique , Petit Jean‐Yves , Brachet Philippe 
Published: February 2011

AbstractChanges in the regional distribution of the metabotropic GABA type B receptors (GABAB) were investigated in a rat model of Huntignton's disease. Animals received a unilateral intrastriatal injection of quinolinic acid (QA), and GABAB immunoreactivity was monitored 3, 11, and 21 days postinjection in the striatum and substantia nigra (SN). Two antibodies, recognizing either the GABAB1 or the GABAB2 receptor subtypes, were used. QA injection rapidly induced a protracted increase in GABAB1 or GABAB2 immunoreactivity in the lesioned striatum, despite the neuronal loss. In the SN, a continuous increase in GABAB1 and GABAB2 immunoreactivity was observed at all time points in the ipsilateral pars reticulata (SNr), whereas the pars compacta (SNc) was unaffected by this phenomenon. This increase was supported by a densitometric analysis. At day 21 postlesion induction, intensely labeled stellate cells and processes were found in the ipsilateral SNr, in addition to immunoreactive neurons. Double labeling of GABAB1 and glial fibrillary acidic protein (GFAP) showed that the stellate cells were reactive astrocytes. Hence, part of the sustained increase in GABAB immunoreactivity that takes place in the SNr and possibly the striatum may be ascribed to reactive astrocytes. It is suggested that GABAB receptors are up‐regulated in these reactive astrocytes and that agonists might influence the extent of this astroglial reaction. © 2011 Wiley‐Liss, Inc.
Regulation of cytokine expression by Schwann cells in response to α2‐macroglobulin binding to LRP1
Authors: Shi Yang , Yamauchi Tomonori , Gaultier Alban , Takimoto Shinako , Campana W. Marie , Gonias Steven L. 
Published: February 2011

AbstractBinding of activated α2‐macroglobulin (α2M) to LDL receptor‐related protein‐1 (LRP1) in Schwann cells activates ERK/MAP kinase and Akt and thereby promotes cell survival and migration. The goal of this study was to determine whether α2M binding to LRP1 regulates expression of cytokines and chemokines. To assess the LRP1 response selectively, we studied primary cultures of rat Schwann cells. In a screening assay that detects 84 gene products, monocyte chemoattractant protein‐1 (MCP‐1/CCL2) mRNA expression was increased more than 13‐fold in Schwann cells treated with activated α2M. The effects of α2M on MCP‐1 expression were selective, because expression of the general proinflammatory cytokine tumor necrosis factor‐α (TNF‐α) was not induced. We confirmed that α2M selectively induces expression of MCP‐1 and not TNF‐α in single‐target qPCR assays. MCP‐1 protein accumulated at increased levels in conditioned medium of α2M‐treated cells. LRP1 was necessary for induction of MCP‐1 expression, as determined in experiments with the LRP1 antagonist receptor‐associated protein, a mutated form of full‐length α2M that does not bind LRP1, and in studies with Schwann cells in which LRP1 was silenced. Inhibiting ERK/MAP kinase activation blocked expression of MCP‐1. These studies support a model in which LRP1 regulates multiple aspects of Schwann cell physiology in the response to PNS injury. © 2011 Wiley‐Liss, Inc.
Calpeptin attenuated apoptosis and intracellular inflammatory changes in muscle cells
Authors: Nozaki Kenkichi , Das Arabinda , Ray Swapan K. , Banik Naren L. 
Published: February 2011

AbstractIn idiopathic inflammatory myopathies (IIMs), extracellular inflammatory stimulation is considered to induce secondary intracellular inflammatory changes including expression of major histocompatibility complex class‐I (MHC‐I) and to produce a self‐sustaining loop of inflammation. We hypothesize that activation of calpain, a Ca2+‐sensitive protease, bridges between these extracellular inflammatory stress and intracellular secondary inflammatory changes in muscle cells. In this study, we demonstrated that treatment of rat L6 myoblast cells with interferon‐γ (IFN‐γ) caused expression of MHC‐I and inflammation‐related transcription factors (phosphorylated‐extracellular signal‐regulated kinase 1/2 and nuclear factor‐κB). We also demonstrated that treatment with tumor necrosis factor‐α (TNF‐α) induced apoptotic changes and activation of calpain and cyclooxygenase‐2. Furthermore, we found that posttreatment with calpeptin attenuated the intracellular changes induced by IFN‐γ or TNF‐α. Our results indicate that calpain inhibition attenuates apoptosis and secondary inflammatory changes induced by extracellular inflammatory stimulation in the muscle cells. These results suggest calpain as a potential therapeutic target for treatment of IIMs. © 2011 Wiley‐Liss, Inc
Trimethyltin initially activates the caspase 8/caspase 3 pathway for damaging the primary cultured cortical neurons derived from embryonic mice
Authors: Kuramoto Nobuyuki , Seko Keiichi , Sugiyama Chie , Shuto Makoto , Ogita Kiyokazu 
Published: February 2011

AbstractThe organotin trimethyltin (TMT) is well known to cause neuronal damage in the central nervous system. To elucidate the mechanisms underlying the toxicity of TMT toward neurons, we prepared primary cultures of neurons from the neocortex of mouse embryos. A continuous exposure to TMT produced a decrease in cell viability as well as an increase in the number of cells with nuclear condensation/shrinkage at the exposure time window up to 24 hr. In addition to the events at the early time window, lactate dehydrogenase released was significantly elevated at the later exposure time from 36 to 48 hr. With a 3‐hr exposure to TMT, a significant increase was observed in the activity of caspase 8, but not in that of caspase 9. TMT exposure produced no elevation in the level of cytochrome c released from mitochondria until 12 hr of exposure, with a significant facilitation of cytochrome c release at the exposure times of 16 and 24 hr. After the activation of caspase 8 by TMT exposure, caspase 3 activation and nuclear translocation of caspase‐activated DNase were caused by exposure for 6 hr or longer. However, nuclear DNase II was elevated at the later time window of exposure. A caspase inhibitor completely prevented TMT from damaging the cells in any time window. Taken together, our data are the first demonstration that TMT toxicity is initially caused by activation of the caspase 8/caspase 3 pathway for nuclear translocation of DNases in cortical neurons in primary culture. © 2011 Wiley‐Liss, Inc.
Waste not, want not: Leading the lean health‐care journey at Seattle Children's Hospital
Authors: Hagan Pat 
Published: February 2011

AbstractOf the work conducted by health‐care practitioners, 95 percent has no value to the patients they serve—an astounding fact given the spiraling costs of medical care. How well a health‐care organization delivers care lies in the crucial remaining 5 percent. Borrowing techniques from the manufacturing sector, Seattle Children's Hospital in Washington has embarked on a continuous improvement initiative that has streamlined the hospital's myriad processes at all levels to ensure high‐quality and effective delivery of services. As this case study shows, the organization, its staff members at all levels, and its patients are all beneficiaries of the hospital's healthy focus on continuous performance improvement. © 2011 Wiley Periodicals, Inc.
Ionic liquid stationary phases for gas chromatography
Authors: Poole Colin F. , Poole Salwa K. 
Published: February 2011

AbstractThis article provides a summary of the development of ionic liquids as stationary phases for gas chromatography beginning with early work on packed columns that established details of the retention mechanism and established working methods to characterize selectivity differences compared with molecular stationary phases through the modern development of multi‐centered cation and cross‐linked ionic liquids for high‐temperature applications in capillary gas chromatography. Since there are many reviews on ionic liquids dealing with all aspects of their chemical and physical properties, the emphasis in this article is placed on the role of gas chromatography played in the design of ionic liquids of low melting point, high thermal stability, high viscosity, and variable selectivity for separations. Ionic liquids provide unprecedented opportunities for extending the selectivity range and temperature‐operating range of columns for gas chromatography, an area of separation science that has otherwise been almost stagnant for over a decade.
Experimental and quantum chemical studies on two triazole derivatives as corrosion inhibitors for mild steel in acid media
Authors: Li W. , Hu L. , Tao Z. , Tian H. , Hou B. 
Published: February 2011

AbstractTwo triazole derivatives [1‐phenyl‐2‐(5‐(1,2,4) triazol‐1‐ylmethyl‐(1,3,4) oxadizaol‐2‐ylsulphanyl)‐ethanone (PTOE) and 2‐(4‐tert‐butyl‐benzylsulphanyl)‐5‐(1,2,4) triazol‐1‐ylmethyl‐(1,3,4) oxadiazole (TBTO)] were synthesized as new corrosion inhibitors for the corrosion of mild steel in 1 M hydrochloric acid solutions. The inhibiting efficiency of the different inhibitors was evaluated by means of weight loss and electrochemical techniques such as electrochemical impedance spectroscopy (EIS) and polarization curves. The electrochemical investigation results indicate that these compounds act as mixed‐type inhibitors retarding the anodic and cathodic corrosion reactions and do not change the mechanism of either hydrogen evolution reaction or mild steel dissolution. The studied compounds followed the Langmuir adsorption isotherm, and the thermodynamic parameters were determined and discussed. The effect of molecular structure on the inhibition efficiency has been investigated with ab initio calculations. The electronic properties such as highest occupied molecular orbital (HOMO) energy level, lowest unoccupied molecular orbital (LUMO) energy level, dipole moment (µ) and molecular orbital densities were calculated.
Electrochemical corrosion behaviour of Sn–Ag–Cu (SAC) eutectic alloy in a chloride containing environment
Authors: Rosalbino F. , Zanicchi G. , Carlini R. , Angelini E. , Marazza R. 
Published: February 2011

AbstractThe corrosion behaviour of the Sn94.5Ag3.8Cu1.5 (SAC) eutectic alloy was investigated in 0.1 M NaCl solution by potentiodynamic polarization and impedance spectroscopy measurements and compared with that of the conventional Sn73.9Pb23.1 eutectic solder employed for a long time in the packaging of microelectronic components and devices. Scanning electron microscopy (SEM) and electron probe microanalysis (EPMA) were used to characterize the SAC eutectic alloy prior to and after the electrochemical tests. The electrochemical results indicated that the Sn–Ag–Cu eutectic alloy exhibits better corrosion behaviour than the Sn–Pb eutectic solder in NaCl solution. The presence of a corrosion products layer constituted by tin oxy‐chloride was detected at the surface of both alloys investigated after the electrochemical tests. The better corrosion behaviour of SAC eutectic alloy compared to Sn–Pb eutectic solder is ascribed to the formation of a more compact surface film of corrosion products with improved protective properties owing to the presence of copper and silver, as revealed by EPMA.