bluuebunny/crossref_metadata_2025 huggingface dataset:
SOME ASPECTS OF SHAPE PHASE TRANSITION IN EVEN-EVEN NUCLEI
Authors: LIU YU-XIN , HOU ZHAN-FENG , ZHANG YU
Published: February 2009

We have reviewed the study on the signatures of shape phase transition in even-even nuclei and investigated the statistical properties of the E (5) and X (5) symmetries and their location in the Casten's triangle and the effect of some modes of nucleon-nucleon interaction on the nuclear shape phases and their transitions. We show that the ratios of the E 2 transition rates and the ratio of the energies of [Formula: see text] state and the [Formula: see text] state can serve as the effective order parameters not only identifying the nucleon number driven phase transition but also distinguishing the first order one form the second order one. Our calculations show that the states in E (5) and X (5) symmetries are almost regular ones and the X (5) symmetry may actually locate at the middle of the "AW arc" inside the Casten's triangle and the E (5) symmetry at the U (5)- O (6) chain. Our study also indicates that strong or weak monopole-pair interaction leads to a vibration or an axially oblate deformation. While quadrupole-pair and QQ interactions induce deformations. Then a complete shape phase structure of nucleus is given in a study at nucleon level.
GENERALIZATIONS OF COMPLEMENTED RINGS WITH APPLICATIONS TO RINGS OF FUNCTIONS
Authors: KNOX M. L. , LEVY R. , MCGOVERN W. WM. , SHAPIRO J.
Published: February 2009

It is well known that a commutative ring R is complemented (that is, given a ∈ R there exists b ∈ R such that ab = 0 and a + b is a regular element) if and only if the total ring of quotients of R is von Neumann regular. We consider generalizations of the notion of a complemented ring and their implications for the total ring of quotients. We then look at the specific case when the ring is a ring of continuous real-valued functions on a topological space.
INTERSECTION THEORIES AND CHEBYSHEV POLYNOMIALS III
Authors: HUMPHRIES STEPHEN P.
Published: February 2009

We investigate the properties of certain operators that were used in previous papers to create geometric and algebraic intersection number functions. Using these operators we show how to construct a general intersection theory and then we investigate properties of certain polynomials that arise naturally in this context. We indicate connections to twin primes.
CONSTRUCTIVE KRULL DIMENSION I: INTEGRAL EXTENSIONS
Authors: COQUAND THIERRY , DUCOS LIONEL , LOMBARDI HENRI , QUITTÉ CLAUDE
Published: February 2009

We give a constructive approach to the well known classical theorem saying that an integral extension doesn't change the Krull dimension.
GOING-DOWN AND SEMISTAR OPERATIONS
Authors: DOBBS DAVID E. , SAHANDI PARVIZ
Published: February 2009

If D ⊆ T is an extension of (commutative integral) domains and ⋆ (resp., ⋆′) is a semistar operation on D (resp., T), we define what it means for D ⊆ T to satisfy the (⋆,⋆′)-GD property. Sufficient conditions are given for (⋆,⋆′)-GD, generalizing classical sufficient conditions for GD such as flatness, openness of the contraction map of spectra and the hypotheses of the classical going-down theorem. If ⋆ is a semistar operation on a domain D, we define what it means for D to be a ⋆-GD domain, generalizing the notion of a going-down domain. In determining whether a domain D is a [Formula: see text] domain, the domain extensions T of D for which [Formula: see text] is tested can be the [Formula: see text]-valuation overrings of D, the simple overrings of D, or all T. P ⋆ MD s are characterized as the [Formula: see text]-treed (resp., [Formula: see text]) domains D which are [Formula: see text]-finite conductor domains such that [Formula: see text] is integrally closed. Several characterizations are given of the [Formula: see text]-Noetherian domains D of [Formula: see text]-dimension 1 in terms of the behavior of the (⋆,⋆′)-linked overrings of D and the ⋆-Nagata rings Na(D,⋆).
Conformational Pathology of the Serpins: Themes, Variations, and Therapeutic Strategies
Authors: Gooptu Bibek , Lomas David A.
Published: February 2009

Point mutations cause members of the serine protease inhibitor (serpin) superfamily to undergo a novel conformational transition, forming ordered polymers. These polymers characterize a group of diseases termed the serpinopathies. The formation of polymers underlies the retention of α1-antitrypsin within hepatocytes and of neuroserpin within neurons to cause cirrhosis and dementia, respectively. Point mutations of antithrombin, C1 inhibitor, α1-antichymotrypsin, and heparin cofactor II cause a similar conformational transition, resulting in a plasma deficiency that is associated with thrombosis, angioedema, and emphysema. Polymers of serpins can also form in extracellular tissues where they activate inflammatory cascades. This is best described for the Z variant of α1-antitrypsin in which the proinflammatory properties of polymers provide an explanation for both progressive emphysema and the selective advantage of this mutant allele. Therapeutic strategies are now being developed to block the aberrant conformational transitions and so treat the serpinopathies.
Structure and Dynamics of Membrane Proteins by Magic Angle Spinning Solid-State NMR
Authors: McDermott Ann
Published: February 2009

Membrane proteins remain difficult to study by traditional methods. Magic angle spinning solid-state NMR (MAS SSNMR) methods present an important approach for studying membrane proteins of moderate size. Emerging MAS SSNMR methods are based on extensive assignments of the nuclei as a basis for structure determination and characterization of function. These methods have already been used to characterize fibrils and globular proteins and are being increasingly used to study membrane proteins embedded in lipids. This review highlights recent applications to intrinsic membrane proteins and summarizes recent technical advances that will enable these methods to be utilized for more complex membrane protein systems in the near future.
Acetylcholine induces Ca2+ signaling in chicken retinal pigmented epithelial cells during dedifferentiation
Authors: Sekiguchi-Tonosaki Mariko , Obata Masakatsu , Haruki Akira , Himi Toshiyuki , Kosaka Jun
Published: February 2009

Retinal pigmented epithelial cells exchange their cellular phenotypes into lens cells and neurons, via depigmented and non-epithelial-shaped dedifferentiated intermediates. Because these dedifferentiated cells can either revert to pigmented epithelial cells or transdifferentiate into lens cells and/or neurons, they are recognized as candidates for lens and retinal cell regeneration. The purpose of the present study was to elucidate the signal transduction pathways between chicken retinal pigmented epithelial cells and their dedifferentiated intermediates. We monitored intracellular Ca2+ concentrations using Fluo-4-based Ca2+ optical imaging and focused on cellular responses to the neurotransmitter acetylcholine. Muscarinic Ca2+ mobilization was observed both in retinal pigmented epithelial cells and in dedifferentiated cells, and was inhibited by atropine. The muscarine-dependent acetylcholine response depended on Ca2+ release from intracellular Ca2+ stores, which was completely blocked by thapsigargin. In contrast, the nicotine-dependent acetylcholine response that led to Ca2+ influx through L-type Ca2+ channels was inhibited by α-bungarotoxin and attenuated by nifedipine, and it was detected only in the dedifferentiated intermediates. Application of ( S)-(-)-BayK8644 elevated intracellular Ca2+ both in retinal pigmented epithelial cells and in dedifferentiated intermediates; however, the nicotinic response was not observed in pigmented epithelial cells. Another L-type Ca2+ channel blocker, diltiazem, also blocked the nicotine-dependent acetylcholine response in dedifferentiated cells and maintained the epithelial-like morphology of retinal pigmented epithelial cells. Our results indicate that an alternative acetylcholine signaling pathway is used during the dedifferentiation process of retinal pigmented epithelial cells.
The eIF4E-binding proteins are modifiers of cytoplasmic eIF4E relocalization during the heat shock response
Authors: Sukarieh R. , Sonenberg N. , Pelletier J.
Published: February 2009

Stress granules (SGs) arise as a consequence of cellular stress, contain stalled translation preinitiation complexes, and are associated with cell survival during environmental insults. SGs are dynamic entities with proteins relocating into and out of them during stress. Among the repertoire of proteins present in SGs is eukaryotic initiation factor 4E (eIF4E), a translation factor required for cap-dependent translation and that regulates a rate-limiting step for protein synthesis. Herein, we demonstrate that localization of eIF4E to SGs is dependent on the presence of a family of repressor proteins, eIF4E-binding proteins (4E-BPs). Our results demonstrate that 4E-BPs regulate the SG localization of eIF4E.
Chronic hypoxia attenuates VEGF signaling and angiogenic responses by downregulation of KDR in human endothelial cells
Authors: Olszewska-Pazdrak Barbara , Hein Travis W. , Olszewska Paulina , Carney Darrell H.
Published: February 2009

Coronary artery disease results in progressive vascular stenosis associated with chronic myocardial ischemia. Vascular endothelial growth factor (VEGF) stimulates endothelial cell angiogenic responses to revascularize ischemic tissues; however, the effect of chronic hypoxia on the responsiveness of endothelial cells to VEGF remains unclear. We, therefore, investigated whether hypoxia alters VEGF-stimulated signaling and angiogenic responses in primary human coronary artery endothelial (HCAE) cells. Exposure of HCAE cells to hypoxia (1% O2) for 24 h decreased VEGF-stimulated endothelial cell migration (∼82%), proliferation (∼30%), and tube formation. Hypoxia attenuated VEGF-stimulated activation of endothelial nitric oxide (NO) synthase (eNOS) (∼72%) and reduced NO production in VEGF-stimulated cells from 237 ± 38.8 to 61.3 ± 28.4 nmol/l. Moreover, hypoxia also decreased the ratio of phosphorylated eNOS to total eNOS in VEGF-stimulated cells by ∼50%. This effect was not observed in thrombin-stimulated cells, suggesting that hypoxia specifically inhibited VEGF signaling upstream of eNOS phosphorylation. VEGF-induced activation of Akt, ERK1/2, p38, p70S6 kinases, and S6 ribosomal protein was also attenuated in hypoxic cells. Moreover, VEGF-stimulated phosphorylation of VEGF receptor-2 (KDR) at Y996 and Y1175 was decreased by hypoxia. This decrease correlated with a 70 ± 12% decrease in KDR protein expression. Analysis of mRNA from these cells showed that hypoxia reduced steady-state levels of KDR mRNA by 52 ± 16% and decreased mRNA stability relative to normoxic cells. Our findings demonstrate that chronic hypoxia attenuates VEGF-stimulated signaling in HCAE cells by specific downregulation of KDR expression. These data provide a novel explanation for the impaired angiogenic responses to VEGF in endothelial cells exposed to chronic hypoxia.
Plectin contributes to mechanical properties of living cells
Authors: Na Sungsoo , Chowdhury Farhan , Tay Bernard , Ouyang Mingxing , Gregor Martin , Wang Yingxiao , Wiche Gerhard , Wang Ning
Published: February 2009

Plectin is a 500-kDa cross-linking protein that plays important roles in a number of cell functions including migration and wound healing. We set out to characterize the role of plectin in mechanical properties of living cells. Plectin−/− cells were less stiff than plectin+/+ cells, but the slopes of the two power laws in response to loading frequencies (0.002–1,000 Hz) were similar. Plectin−/− cells lost the capacity to propagate mechanical stresses to long distances in the cytoplasm; traction forces in plectin−/− cells were only half of those in plectin+/+ cells, suggesting that plectin deficiency compromised prestress generation, which, in turn, resulted in the inhibition of long distance stress propagation. Both plectin+/+ and plectin−/− cells exhibited nonlinear stress-strain relationships. However, plectin+/+ cells, but not plectin−/− cells, further stiffened in response to lysophosphatidic acid (LPA). Dynamic fluorescence resonance energy transfer analysis revealed that RhoA GTPase proteins were activated in plectin+/+ cells but not in plectin−/− cells after treatment with LPA. Expression in plectin−/− cells of constitutively active RhoA (RhoA-V14) but not a dominant negative mutant of RhoA (RhoA-N19) or an empty vector restored the long distance force propagation behavior, suggesting that plectin is important in normal functions of RhoA. Our findings underscore the importance of plectin for mechanical properties, stress propagation, and prestress of living cells, thereby influencing their biological functions.
State-dependent block of HERG potassium channels byR-roscovitine: implications for cancer therapy
Authors: Ganapathi Sindura B. , Kester Mark , Elmslie Keith S.
Published: February 2009

Human ether-a-go-go-related gene (HERG) potassium channel acts as a delayed rectifier in cardiac myocytes and is an important target for both pro- and antiarrhythmic drugs. Many drugs have been pulled from the market for unintended HERG block causing arrhythmias. Conversely, recent evidence has shown that HERG plays a role in cell proliferation and is overexpressed both in multiple tumor cell lines and in primary tumor cells, which makes HERG an attractive target for cancer treatment. Therefore, a drug that can block HERG but that does not induce cardiac arrhythmias would have great therapeutic potential. Roscovitine is a cyclin-dependent kinase (CDK) inhibitor that is in phase II clinical trials as an anticancer agent. In the present study we show that R-roscovitine blocks HERG potassium current (human embryonic kidney-293 cells stably expressing HERG) at clinically relevant concentrations. The block (IC50= 27 μM) was rapid (τ = 20 ms) and reversible (τ = 25 ms) and increased with channel activation, which supports an open channel mechanism. Kinetic study of wild-type and inactivation mutant HERG channels supported block of activated channels by roscovitine with relatively little effect on either closed or inactivated channels. A HERG gating model reproduced all roscovitine effects. Our model of open channel block by roscovitine may offer an explanation of the lack of arrhythmias in clinical trials using roscovitine, which suggests the utility of a dual CDK/HERG channel block as an adjuvant cancer therapy.
Enhanced pressor response to increased CSF sodium concentration and to central ANG I in heterozygous α2Na+-K+-ATPase knockout mice
Authors: Hou Xiaohong , Theriault Steven F. , Dostanic-Larson Iva , Moseley Amy E. , Lingrel Jerry B , Wu Hengwei , Dean Stephanie , Van Huysse James W.
Published: February 2009

Intracerebroventricular (ICV) infusion of NaCl mimics the effects of a high-salt diet in salt-sensitive hypertension, raising the sodium concentration in the cerebrospinal fluid (CSF [Na]) and subsequently increasing the concentration of an endogenous ouabain-like substance (OLS) in the brain. The OLS, in turn, inhibits the brain Na+-K+-ATPase, causing increases in the activity of the brain renin-angiotensin system (RAS) and blood pressure. The Na+-K+-ATPase α (catalytic)-isoform(s) that mediates the pressor response to increased CSF [Na] is unknown, but it is likely that one or more isoforms that bind ouabain with high affinity are involved (e.g., the Na+-K+-ATPase α2- and/or α3-subunits). We hypothesize that OLS-induced inhibition of the α2-subunit mediates this response. Therefore, a chronic reduction in α2expression via a heterozygous gene knockout (α2+/−) should enhance the pressor response to increased CSF [Na]. Intracerebroventricular (ICV) infusion of artificial CSF containing 0.225 M NaCl increased mean arterial pressure (MAP) in both wild-type (+/+) and α2+/− mice, but to a greater extent in α2+/−. Likewise, the pressor response to ICV ouabain was enhanced in α2+/− mice, demonstrating enhanced sensitivity to brain Na+-K+-ATPase inhibition per se. The pressor response to ICV ANG I but not ANG II was also enhanced in α2+/− vs. α2+/+ mice, suggesting an enhanced brain RAS activity that may be mediated by increased brain angiotensin converting enzyme (ACE). The latter hypothesis is supported by enhanced ACE ligand binding in the organum vasculosum laminae terminalis. These studies demonstrate that chronic downregulation of Na+-K+-ATPase α2-isoform expression by heterozygous knockout increases the pressor response to increased CSF [Na] and activates the brain RAS. Since these changes mimic those produced by the endogenous brain OLS, the brain α2-isoform may be a target for the brain OLS during increases in CSF [Na], such as in salt-dependent hypertension.
The spleen is required for 5-HT1Areceptor agonist-mediated increases in mean circulatory filling pressure during hemorrhagic shock in the rat
Authors: Tiniakov Ruslan , Scrogin Karie E.
Published: February 2009

The 5-HT1Areceptor agonist, 8- OH-DPAT, increases whole body venous tone (mean circulatory filling pressure; MCFP), and attenuates metabolic acidosis in a rat model of unresuscitated hemorrhagic shock. To determine whether improved acid-base balance was associated with sympathetic activation and venous constriction, MCFP, sympathetic activity (SA), and blood gases were compared in hemorrhaged rats following administration of 5-HT1Areceptor agonist 8-OH-DPAT, the arterial vasoconstrictor arginine vasopressin (AVP), or saline. To further determine whether protection of acid-base balance was dependent on splenic contraction and blood mobilization, central venous pressure (CVP), MCFP, and blood gases were determined during hemorrhage and subsequent 8-OH-DPAT-administration in rats subjected to real or sham splenectomy. Subjects were hemorrhaged to an arterial pressure of 50 mmHg for 25 min and subsequently were treated with 8-OH-DPAT (30 nmol/kg iv), AVP titrated to match the pressor effect of 8-OH-DPAT (∼2 ng/min iv), or infusion of normal saline. 8-OH-DPAT increased MAP, CVP, MCFP, and SA, and decreased lactate accumulation. AVP did not affect CVP or SA, but raised MCFP slightly to a level intermediate between 8-OH-DPAT- and saline-treated rats. Infusion of AVP also produced a modest protection against metabolic acidosis. Splenectomy prevented the rise in CVP, MCFP, and protection against metabolic acidosis produced by 8-OH-DPAT but had no effect on the immediate pressor response to the drug. Together, the data indicate that 8-OH-DPAT produces a pattern of cardiovascular responses consistent with a sympathetic-mediated venoconstriction that is, in part, responsible for the drug's beneficial effect on acid-base balance. Moreover, blood mobilization stimulated by the spleen is required for the beneficial effects of 8-OH-DPAT.
Aquaporin-2 abundance in the renal collecting duct: new insights from cultured cell models
Authors: Hasler Udo , Leroy Valérie , Martin Pierre-Yves , Féraille Eric
Published: February 2009

The renal cortico-papillary osmotic gradient is generated by sodium reabsorption in the thick ascending limb. The antidiuretic hormone arginine vasopressin (AVP) increases collecting duct water permeability by enhancing aquaporin-2 (AQP2) water channel insertion in the apical membrane of principal cells, allowing water to passively flow along the osmotic gradient from the tubule lumen to the interstitium. In addition to short-term AQP2 redistribution between intracellular compartments and the cell surface, AQP2 whole cell abundance is tightly regulated. AVP is a major transcriptional activator of the AQP2 gene, and stimulation of insulin- and calcium-sensing receptors respectively potentiate and reduce its action. Extracellular tonicity is another key factor that determines the levels of AQP2 abundance. Its effect is dependent on activation of the tonicity-responsive enhancer binding protein that reinforces AVP-induced AQP2 transcriptional activation. Conversely, activation of the NF-κB transcriptional factor by proinflammatory factors reduces AQP2 gene transcription. Aldosterone additionally regulates AQP2 whole cell abundance by simultaneously reducing AQP2 gene transcription and stimulating AQP2 mRNA translation. These examples illustrate how cross talk between various stimuli regulates AQP2 abundance in collecting duct principal cells and consequently contributes to maintenance of body water homeostasis.
Altered Hippocampal Synaptic Plasticity in the Fmr1 Gene Family Knockout Mouse Models
Authors: Zhang Jing , Hou Lingfei , Klann Eric , Nelson David L.
Published: February 2009

Fragile X syndrome (FXS) is the most common form of inherited mental retardation. The syndrome results from the absence of the fragile X mental retardation protein (FMRP), which is encoded by the fragile X mental retardation 1 ( FMR1) gene. FMR1 and its two paralogs, fragile X–related genes 1 and 2 ( FXR1 and -2), form the Fmr1 gene family. Here, we examined long-lasting synaptic plasticity in Fmr1 knockout, Fxr2 knockout, and Fmr1/ Fxr2 double knockout mice. We found that metabotropic glutamate receptor–dependent long-term depression (mGluR-LTD) in the hippocampus was affected in Fmr1 knockout, Fxr2 knockout, and Fmr1/ Fxr2 double knockout mice at young ages (4–6 wk old). In addition, Fmr1/ Fxr2 double knockout mice showed significant deficiencies relative to either Fmr1 or Fxr2 knockout mice in baseline synaptic transmission and short-term presynaptic plasticity, suggesting FMRP and FXR2P may contribute in a cooperative manner to pathways regulating presynaptic plasticity. However, compared with wild-type littermates, late-phase long-term potentiation (L-LTP) was unaltered in all knockout mice at 4–6 mo of age. Interestingly, although Fmr1/ Fxr2 double knockout mice exhibited a more robust enhancement in mGluR-LTD compared with that in Fmr1 knockout mice, Fxr2 knockout mice exhibited reduced mGluR-LTD. Furthermore, unlike Fmr1 knockout mice, mGluR-LTD in Fxr2 knockout mice required new protein synthesis, whereas mGluR-LTD in Fmr1/ Fxr2 double knockout mice was partially dependent on protein synthesis. These results indicated that both FMRP and FXR2P function in synaptic plasticity and that they likely operate in related but independent pathways.
Differential Metabotropic Glutamate Receptor Expression and Modulation in Two Neocortical Inhibitory Networks
Authors: Sun Qian-Quan , Zhang Zhi , Jiao Yuanyuan , Zhang Chunzhao , Szabó Gábor , Erdelyi Ferenc
Published: February 2009

Taking advantage of transgenic mice with genetically labeled GABA-releasing interneurons, we examined the cell-specific patterns of mGluR expression in two broadly defined subtypes of inhibitory interneurons in layer IV of somatosensory cortex. Electrophysiological recording combined with application of specific agonists for specific mGluRs demonstrated different effects of mGluR activation in fast-spiking (FS) versus regular spiking nonpyramidal (RSNP) interneurons. Whereas activation of group I, II, and III mGluRs inhibited excitatory synaptic transmission in RSNP neurons predominantly via postsynaptic mechanisms, group I mGluR activation depolarized FS but not RSNP interneurons. Immunoreactivities of mGluR1, mGluR5, mGluR2/3, and mGluR8 exhibited different cellular expression patterns in the two groups of neurons that were not entirely consistent with physiological and pharmacological experiments. Taken together, our data indicate cell and circuit-specific roles for mGluRs in modulating inhibitory circuits in the somatosensory cortex. These results help to reinforce the concept that RSNP and FS cells represent morphologically, physiologically, and functionally distinct groups of interneurons. The results reported here help to increase our understanding of the roles of mGluRs in endogenous glutamatergic-induced plasticity of interneuronal networks.
Maturation of Excitatory Synaptic Transmission of the Rat Nucleus Accumbens From Juvenile to Adult
Authors: Kasanetz Fernando , Manzoni Olivier J.
Published: February 2009

Precise control of synaptic strength is critical for maintaining accurate network activity and normal brain functions. Several major brain diseases are related to synaptic alterations in the adult brain. Detailed descriptions of the normal physiological properties of adult synapses are scarce, mainly because of the difficulties in performing whole cell patch-clamp recording in brain slices from adult animals. Here we present the portrait of excitatory synapses and intrinsic properties of medium spiny neurons (MSNs) of the nucleus accumbens (NAc), a central structure of the mesocorticolimbic system, from youth (P14) to adulthood (P120). We found that intrinsic neuronal excitability decreased over development, mainly due to an enhancement of potassium conductance and the consequent reduction in membrane resistance. The ratio between paired-pulse synaptic responses was similar in juvenile, adolescent, and adult MSNs, suggesting that the probability of neurotransmitter release was unaltered. α-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (AMPAR)–mediated excitatory postsynaptic currents (EPSCs) decayed more slowly in adult MSN. In contrast, the kinetic properties and the subunit composition of N-methyl-d-aspartate receptor (NMDAR)–mediated EPSC in the NAc were conserved from youth to adulthood. Changes in synaptic strength were estimated from the ratio of AMPAR to NMDAR evoked and spontaneous EPSCs (AMPAR/NMDAR ratio). Although both AMPAR and NMDAR EPSCs decreased over development, there was an increase of the AMPAR/NMDAR ratio that was linked to changes in NMDAR EPSC. Furthermore, distribution of the AMPAR/NMDAR ratio was more heterogeneous in MSNs from adults, suggesting that synaptic strength is continuously refined during life.
Variation in Annual Volume at a University Hospital Does Not Predict Mortality for Pancreatic Resections
Authors: Mukhtar Rita A. , Kattan Omar M. , Harris Hobart W.
Published: February 2009

Annual volume of pancreatic resections has been shown to affect mortality rates, prompting recommendations to regionalize these procedures to high-volume hospitals. Implementation has been difficult, given the paucity of high-volume centers and the logistical hardships facing patients. Some studies have shown that low-volume hospitals achieve good outcomes as well, suggesting that other factors are involved. We sought to determine whether variations in annual volume affected patient outcomes in 511 patients who underwent pancreatic resections at the University of California, San Francisco between 1990 and 2005. We compared postoperative mortality and complication rates between low, medium, or high volume years, designated by the number of resections performed, adjusting for patient characteristics. Postoperative mortality rates did not differ between high volume years and medium/low volume years. As annual hospital volume of pancreatic resections may not predict outcome, identification of actual predictive factors may allow low-volume centers to achieve excellent outcomes.
Protective Actions of PPAR‐γ Activation in Renal Endothelium
Authors: Westerweel Peter E. , Verhaar Marianne C.
Published: February 2009

Renal endothelial damage is pivotal in the initiation and progression of renal disease. Damaged
renal endothelium may be regenerated through proliferation of local endothelium and circulation‐derived
endothelial progenitor cells. Activation of the PPAR‐γ‐receptors present on endothelial cells affects their
cellular behavior. Proliferation, apoptosis, migration, and angiogenesis by endothelial cells are modulated,
but may involve both stimulation and inhibition depending on the specific circumstances. PPAR‐γ‐receptor
activation stimulates the production of nitric oxide, C‐type natriuretic peptide, and superoxide dismutase,
while endothelin‐1 production is inhibited. Together, they augment endothelial function, resulting in blood
pressure lowering and direct renoprotective effects. The presentation of adhesion molecules and release
of cytokines recruiting inflammatory cells are inhibited by PPAR‐γ‐agonism. Finally, PPAR‐γ‐receptors are
also found on endothelial progenitor cells and PPAR‐γ‐agonists stimulate progenitor‐mediated endothelial repair.
Together, the stimulatory effects of PPAR‐γ‐agonism on endothelium make an important contribution to the
beneficial actions of PPAR‐γ‐agonists on
renal disease.
Guidance of Vascular Development
Authors: Larrivée Bruno , Freitas Catarina , Suchting Steven , Brunet Isabelle , Eichmann Anne
Published: February 2009

The vascular system of vertebrates consists of an organized, branched network of arteries, veins, and capillaries that penetrates all the tissues of the body. One of the most striking features of the vascular system is that its branching pattern is highly stereotyped, with major and secondary branches forming at specific sites and developing highly conserved organ-specific vascular patterns. The factors controlling vascular patterning are not yet completely understood. Recent studies have highlighted the anatomic and structural similarities between blood vessels and nerves. The 2 networks are often aligned, with nerve fibers and blood vessels following parallel routes. Furthermore, both systems require precise control over their guidance and growth. Several molecules with attractive and repulsive properties have been found to modulate the proper guidance of both nerves and blood vessels. These include the Semaphorins, the Slits, and the Netrins and their receptors. In this review, we describe the molecular mechanisms by which blood vessels and axons achieve proper path finding and the molecular cues that are involved in their guidance.
MicroRNAs As Novel Regulators of Angiogenesis
Authors: Suárez Yajaira , Sessa William C.
Published: February 2009

MicroRNAs are short noncoding RNAs that function as negative regulators of gene expression. Posttranscriptional regulation by miRNAs is important for many aspects of development, homeostasis, and disease. Endothelial cells are key regulators of different aspects of vascular biology, including the formation of new blood vessels (angiogenesis). Here, we review the approaches and current experimental evidence for the involvement of miRNAs in the regulation of the angiogenic process and their potential therapeutic applications for vascular diseases associated with abnormal angiogenesis.
Anti-Opium Visual Propaganda and the Deglamorisation of Opium in China, 1895–1937
Authors: Paulès Xavier
Published: February 2009

An ambiguous image of opium prevailed before the 1890s. At that time, despite opponents who often warned of the physical and moral damage it caused, the drug was considered to have positive aspects. In particular, opium was an expression of wealth and a wonderful way to socialise, and its analgesic properties made it the equivalent of a panacea. But from the last decade of the nineteenth century onwards, anti-opium visual propaganda succeeded in imposing the cliché of the smoker as a skinny man dressed in rags. This way of representing smokers went far beyond the limits of specialised anti-opium posters and publications: it became, indeed, almost universal. The use of skinniness to portray opium smokers contributed to creating a system whereby the opium smoker was tagged as a destitute person, of a low social position. This successful 'deglamorisation' of opium drove more and more people to turn away from the use of the drug. It is a crucial factor in explaining why consumption was much less alarming in the 1920s and 1930s than it used to be in the late nineteenth century.
Living on Past Glories and Future Dreams The Effects of Depopulation on Early Modern Urban Development in the Former Castle Town of Kanazawa
Authors: Phillipps Jeremy
Published: February 2009

Depopulation of urban areas is a serious issue in twenty-first century Japan, as shown by the recent large-scale amalgamation of municipalities and programmes to combat declining central city areas. However, this is not the first time depopulation has had a significant effect on urban development: the decline in castle towns after the Meiji Restoration of 1868 had profound effects on both urban form and development concepts. Kanazawa, once one of the largest cities in Japan, suffered from an initial and long-lasting drop and then a more insidious decline as its Japan Sea coast location cut it off from the bulk of industrial and trade development. This article uses a two-fold approach to examine depopulation: first, an examination of the physical effects of depopulation based on statistical analysis of pre-war land registers shows the patterns of decline and regrowth throughout the modern period. Second, the impact of depopulation on the city's image of itself is examined through period documents such as council records and local newspapers. The need to regain status through population rank became an overarching goal of the urban leaders, and formed the basis of Kanazawa's reactions to the modern era and eventually towards imperialism.
Three-Week Re-Education to Koreanness
Authors: Prébin Elise
Published: February 2009

Today, international adoptees are welcomed to South Korea by the government, adoption agencies and different associations. These institutions organise educational programmes called 'cultural programmes'. Relatively cheap, these programmes generally include a tour of South Korea, visits to welfare facilities, and classes related to Korean culture: music, language, history, cuisine, martial arts. International adoptees are seen as Koreans of the diaspora, and as such need re-education to discover their true identity. When they return to their adoptive countries, they will be able to represent their birth country accurately and therefore contribute to Korea's successful globalisation. However, what is at stake in these programmes is less political and economical than social. I argue that most of the activities can be viewed as rites of passage and that the entire programme is constructed according to that logic. As a problematic category, international adoptees must be redefined by ritualised actions inside South Korean society. Recent studies considered these ceremonies as mock rituals; however, this article aims to show that these rituals have a valid purpose although they lead not to integration but to separation: defining the diaspora continues to rely on defining what is outside the national territory.
We and the Plural Subject
Authors: de Bruin Boudewijn
Published: February 2009

Margaret Gilbert's plural subject theory defines social collectives in terms of common knowledge of expressed willingness to participate in some joint action. The author critically examines Gilbert's application of this theory to linguistic phenomena involving “we,” arguing that recent work in linguistics provides the tools to develop a superior account. The author indicates that, apart from its own relevance, one should care about this critique because Gilbert's claims about the first person plural pronoun play a role in the argument in favor of her recent theory of political obligation.
Reasons for Relocation to Retirement Communities
Authors: Bekhet Abir K. , Zauszniewski Jaclene A. , Nakhla Wagdy E.
Published: February 2009

The purpose of this qualitative study is to understand the reasons why elders move to retirement communities and what living in retirement communities is like from the perspective of relocated elders. Several themes emerged following qualitative analysis. The themes reflect three categories, labeled as “pushing” factors, “pulling” factors, and “overlapping” factors. Pushing factors included own or spouse's failing health, getting rid of responsibilities, not helped, facility closed out, and loneliness. Pulling factors were location, familiarity and reputation of the facility, security, and joining friends. The third category reflected both pushing and pulling factors, which overlapped and constituted their reason for moving. The findings help to inform the planning of tailored interventions to address elders' special needs or concerns associated with relocation.
Some Studies on HAF Reinforced Epoxy Composites
Authors: Rozik N.N. , Asaad J.N. , Iskander B.A. , Abd-El-Messieh S.L.
Published: February 2009

Epoxy composites loaded with different concentrations (5—50 wt%) of high abrasion furnace carbon black (HAF) with and without the addition of 10 wt% Mg(OH)2 were prepared and subjected to electrical, mechanical, flammability, and thermal measurements. It was found that the permittivity ε' and dielectric loss ε'' increased by increasing HAF content. This increase is slightly lowered by the addition of Mg(OH)2. The electrical conductivity of HAF-epoxy composites increased from the pure polymer towards that of pure carbon. A low frequency region with relaxation time τ 1 in the range 3.5—4.5 × 10-4 s is found to be unaffected by either filler content or the presence of Mg(OH)2. The higher frequency range with relaxation time τ2 is nearly the same for lower concentrations of HAF up to 10 wt% (percolation threshold concentration). Above this concentration a dramatic increase was noticed.

Incorporation of 10 wt% of HAF led to an increase in the compressive strength value. Further increase in HAF content resulted in a decrease in compressive strength values. The tensile strength values of the composite samples before and after the addition of 10 wt% Mg(OH)2 are higher than that of the unloaded one.

The addition of 10 wt% Mg(OH)2 improved both the thermal stability and the fire retardant efficiency of HAF—epoxy composites.
Mechanical Properties of Injection-molded Natural Fiber-reinforced Polypropylene Composites: Formulation and Compounding Processes
Authors: Sun Zhan-Ying , Han Hai-Shan , Dai Gan-Ce
Published: February 2009

In this study, the effects of material optimization and compounding processes on the properties of natural fiber composites were studied. The thermal stabilities of sisal fiber and jute fiber were compared by thermogravimetric analysis. The influences of fiber content, coupling agent, fiber geometry, and fiber distribution on the properties were also researched. It was observed that sisal fiber had more thermal stability than jute fiber. Addition of coupling agent, long fiber length, and uniform fiber distribution led to higher performance composites. For the sisal fiber-reinforced polypropylene composites, the critical fiber length was 2.27 mm and the interfacial shear strength was 22.03 MPa with MAPP. The tensile strength of composites was also theoretically predicted based on Kelly—Tyson model.
The Influence of Carbon Fiber Content on the Tribological Properties of PA6 Composites
Authors: Li J. , Xia Y.C.
Published: February 2009

The tribological performance of PA6 and carbon fiber-reinforced polyamide 6 (CF/PA6) under dry sliding condition was examined. Different contents of carbon fibers were employed as reinforcement. All filled and unfilled polyamide 6 composites were tested against CGr15 ball and representative testing was performed. The effects of carbon fiber content on tribological properties of the composites were investigated. All filled polyamide 6 has superior tribological characteristics to unfilled polyamide 6. The optimum wear reduction is obtained when the content of carbon fiber is 20 vol%.
Axial Experiment on CFRP Confined Steel Reinforced Concrete Columns with Partial Deteriorated Strength
Authors: Hua Wei  , Zhimin Wu  , Peng Zhang
Published: February 2009

This paper aims to investigate the mechanical behavior of columns with partial deteriorated strength and to evaluate the availability of the partial confinement. Five steel reinforced concrete columns have been tested. Different layers of CFRP sheets have been wrapped on the deteriorated strength part. Columns are subjected to axial compression until failure. Axial load, and axial and transverse strains are measured to investigate confinement levels supplied by CFRP sheets. Experimental results indicate that both the load capacity and the ductility of the deteriorated strength part could be significantly increased, subsequently; the load capacity of the entire column can be enhanced higher than those of the original columns. An existing analytical model on FRP reinforcement is used to predict the ultimate load and to evaluate the improvement effectiveness of partial confinement. The prediction provided by theoretical model shows good agreement with the experimental results. Findings of this paper show that partial confinement on deteriorated parts of concrete columns would be developed as an alternative to diminish cost and time consumption in practice.
Suspicious Spatial Distinctions
Authors: Kinloch Valerie
Published: February 2009

In what ways do students understand and document literacies within out-of-school communities in their school-sponsored writings? How can community literacy sites and public perceptions of community disrepair stimulate students to create written responses on the politics of place? These questions are at the heart of this article's investigation into relationships between writing and contexts. Drawing on research in writing and place as well as in out-of-school literacies, the author examines undergraduate writing students' investigations of literacy practices and acts of meaning making. She details how these acts can motivate students to both document and critique literacies within a local urban community in close proximity to their university setting. The author concludes by discussing how students critiqued forms of community literacies through writing, acts that have implications for the ways writing researchers can work to bridge distances (e.g., cultural, sociological, ideological, political) across school and community spaces.
Relationship Between Blood Lead Concentration And Nutritional Status Among Malay Primary School Children In Kuala Lumpur, Malaysia
Authors: Elias SM , Hashim Z. , Marjan ZM , Abdullah AS , Hashim JH
Published: February 2009

A cross-sectional study was conducted to identify the relationship between blood lead concentration and nutritional status among primary school children in Kuala Lumpur. A total of 225 Malay students, 113 male and 112 female, aged 6.3 to 9.8 were selected through a stratified random sampling method. The random blood samples were collected and blood lead concentration was measured by a Graphite Furnace Atomic Absorption Spectrophotometer. The nutrient intake was determined by the 24-hour Dietary Recall method and Food Frequency Questionnaire. An anthropometric assessment was reported according to growth indices (z-scores of weight-for-age, height-for-age, and weight-for-height). The mean blood lead concentration was low (3.4 ± 1.91 ug/dL) and was significantly different between gender. Only 14.7% of the respondents fulfilled the daily energy requirement. The protein and iron intakes were adequate for a majority of the children. However, 34.7% of the total children showed inadequate intake of calcium. The energy, protein, fat and carbohydrate intakes were significantly different by gender, that is, males had better intake than females. Majority of respondents had normal mean z-score of growth indices. Ten percent of the respondents were underweight, 2.8% wasted and 5.4% stunted. Multiple linear regression showed inverse significant relationships between blood lead concentration with children's age (β= -0.647, p<0.001) and per capita income (β=-0.001, p=0.018). There were inverse significant relationships between blood lead concentration with children's age (β=-0.877, p=0.001) and calcium intake (β= -0.011, p=0.014) and positive significant relationship with weight-for-height (β=0.326, p=0.041) among those with inadequate calcium intake. Among children with inadequate energy intake, children's age (β= -0.621, p< 0.001), per capita income (β= -0.001, p=0.025) and protein intake (β= -0.019, p=0.027) were inversely and significantly related with blood lead concentration. In conclusion, nutritional status might affect the children's absorption of lead and further investigation is required for confirmation. Asia Pac J Public Health 2007; 19(3): 29-37.
Guest at Hospice: Time for Consideration
Authors: Warrén Stomberg Margareta
Published: February 2009

This study focuses on daily life situation of terminally ill guests residing at a hospice. In the study, interviews were conducted with 9 such guests. Data were analyzed using a method similar to content analysis. Categories emerged that were related to aspects regarded as external and internal essentials for the well-being of the individual at the hospice. These essentials were as follows: encouragement from the staff, the alleviation of pain, a pleasant and calm atmosphere at the hospice, the significance of visits from relatives, the regret of not being able to take care of oneself, and time to reconcile to one’s life. These results not only show the need for close community with both family and staff but also the need for privacy to reflect on life.
Trends in HIV/TB Coinfection in Trinidad and Tobago for the Period 1998-2007
Authors: Mungrue Kameel , Beharry Andrew , Kalloo Jason , Mahabir Sunita , Maraj Tishan , Ramoutar Ryan , Ramsaroop K. , Solomon Viren
Published: February 2009

Objectives. The aim of this study was to extend the description of the epidemiologic pattern of human immunodeficiency virus (HIV)/tuberculosis (TB) coinfection from 1998 to 2007 in a high HIV/AIDS prevalence country. Design and Methods. This study utilized registry data to determine yearly TB incidence and HIV coinfection. Mortality rates for coinfected patients were calculated and compared with patients receiving highly active antiretroviral therapy (HAART). Results. From a TB population of 2010 registered patients, data was collected on the 466 patients with HIV/TB coinfection. The coinfection rate was found to be 23.6% for the study period. Patients on HAART were twice as likely to survive. Discussion and Conclusions. The incidence of TB and HIV/TB coinfection rates continues to be major challenges in the developing world. Demographic, socioeconomic trends as well as risk factors remain unchanged. Increased HIV screening and HAART coverage offers hope for the future.
Supercharged blood coagulation
Authors: Krishnaswamy Sriram
Published: February 2009

In this issue of Blood, Undas and colleagues show that patients with AMI are able to mount an enhanced blood clotting response in the peripheral microvasculature.
Long-lived life: a detriment
Authors: Boxer Laurence A.
Published: February 2009

In this issue of Blood, Fernandez-Boyanapalli and colleagues report that macrophages isolated from X-linked CGD mice exhibit decreased recognition and removal of apoptotic inflammatory cells secondary to attenuated endogenous IL-4 production.